Knee Orthoses

None

For any item to be covered by Medicare, it must 1) be eligible for a defined Medicare benefit category, 2) be reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member, and 3) meet all other applicable Medicare statutory and regulatory requirements.

The purpose of a Local Coverage Determination (LCD) is to provide information regarding “reasonable and necessary” criteria based on Social Security Act § 1862(a)(1)(A) provisions.

In addition to the “reasonable and necessary” criteria contained in this LCD there are other payment rules, which are discussed in the following documents, that must also be met prior to Medicare reimbursement:

• The LCD-related Standard Documentation Requirements Article, located at the bottom of this policy under the Related Local Coverage Documents section.

• The LCD-related Policy Article, located at the bottom of this policy under the Related Local Coverage Documents section.

• Refer to the Supplier Manual for additional information on documentation requirements.

• Refer to the DME MAC web sites for additional bulletin articles and other publications related to this LCD.

For the items addressed in this LCD, the “reasonable and necessary” criteria, based on Social Security Act § 1862(a)(1)(A) provisions, are defined by the following coverage indications, limitations and/or medical necessity.

For knee orthoses definitions of off-the-shelf and custom fitted, refer to the CODING GUIDELINES section in the LCD-related Policy Article.

PREFABRICATED KNEE ORTHOSES (L1810, L1812, L1820, L1821, L1830, L1831, L1832, L1833, L1836, L1843, L1845, L1847, L1848, L1850, L1851, L1852):

A knee flexion contracture is a condition in which there is shortening of the muscles and/or tendons with the resulting inability to bring the knee to 0 degrees extension or greater (i.e., hyperextension) by passive range of motion. (0 degrees knee extension is when the femur and tibia are in alignment in a horizontal plane). A knee extension contracture is a condition in which there is shortening of the muscles and/or tendons with the resulting inability to bring the knee to 80 degrees flexion or greater by passive range of motion. A contracture is distinguished from the temporary loss of range of motion of a joint following injury, surgery, casting, or other immobilization.

A knee orthosis with joints (L1810, L1812) or knee orthosis with condylar pads and joints with or without patellar control (L1820, L1821) are covered for ambulatory beneficiaries who have weakness or deformity of the knee and require stabilization.

If an L1810, L1812, L1820 or L1821 is provided but the criteria above are not met, the orthosis will be denied as not reasonable and necessary.

A knee orthosis with a locking knee joint (L1831) or a rigid knee orthosis (L1836) is covered for beneficiaries with flexion or extension contractures of the knee with movement on passive range of motion testing of at least 10 degrees (i.e., a nonfixed contracture) (refer to the Group 1 ICD-10 Codes in the LCD-related Policy Article).

If an L1831 or L1836 orthosis is provided but the criterion above is not met, the orthosis will be denied as not reasonable and necessary.

There is no proven clinical benefit to the inflatable air bladder incorporated into the design of code L1847 or L1848; therefore, claims for code L1847 or L1848 will be denied as not reasonable and necessary.

An immobilizer knee orthosis without joints (L1830) is covered for a beneficiary who has had a recent injury to or a surgical procedure on the knee(s) (refer to the Group 2 or Group 4 ICD-10 Codes in the LCD-related Policy Article).

A knee orthosis with adjustable knee joints (L1832, L1833) is covered if one of the following criteria is met:

1. The beneficiary has had a recent injury to or a surgical procedure on the knee(s) (refer to the Groups 2 or Group 4 ICD-10 Codes in the LCD-related Policy Article); or,
2. The beneficiary is ambulatory and has knee instability (refer to the Group 4 ICD-10 Codes in the LCD-related Policy Article).

A prefabricated Swedish type knee orthosis (L1850) is covered for a beneficiary who is ambulatory and has knee instability due to genu recurvatum - hyperextended knee, congenital or acquired (refer to the Group 5 ICD-10 Codes in the LCD-related Policy Article).

For a knee orthosis with adjustable knee joints or a prefabricated Swedish type knee orthosis (L1832, L1833, L1850), objective knee instability must be supported by documentation of the beneficiary’s physical examination including the joint laxity test(s) performed (see the POLICY SPECIFIC DOCUMENTATION REQUIREMENTS section in the LCD-related Policy Article).

A knee orthosis with single or double upright, adjustable flexion and extension joint, medial-lateral and rotation control, with or without varus/valgus adjustment (L1843, L1845, L1851, L1852) is covered if one of the following criteria (1-3) is met:

1. The beneficiary is ambulatory and has objective knee instability that must be supported by documentation of a physical examination including the joint laxity test(s) performed (see the POLICY SPECIFIC DOCUMENTATION REQUIREMENTS section in the LCD-related Policy Article; refer to the Group 4 ICD-10 Codes in the LCD-related Policy Article); or,

2. The beneficiary has had a recent injury to or a surgical procedure on the knee(s) (refer to the Groups 2 or Group 4 ICD-10 Codes in the LCD-related Policy Article); or,

3. The beneficiary has a documented (see the POLICY SPECIFIC DOCUMENTATION REQUIREMENTS section in the LCD-related Policy Article) diagnosis of medial or lateral tibiofemoral osteoarthritis (refer to the Group 6 ICD-10 Codes in the LCD-related Policy Article), and meets all criteria (a-d):

a. The beneficiary is ambulatory; and,

b. The beneficiary is experiencing pain or reduction in their mobility and/or function secondary to the medial or lateral tibiofemoral osteoarthritis; and,

c. The knee orthosis provides either varus or valgus adjustment; and,

d. The beneficiary expresses a willingness to use the knee orthosis.

Claims for L1832, L1833, L1843, L1845, L1850, L1851 or L1852 will be denied as not reasonable and necessary when the beneficiary does not meet the above criteria for coverage. 

“Addition” codes are grouped into four (4) categories in relation to knee orthosis base codes.

• Eligible for separate payment

• Not reasonable and necessary

• Not separately payable

• Incompatible

The following table lists addition codes which describe components or features that can be and frequently are physically incorporated in the specified prefabricated base orthosis. Addition codes may be separately payable if:

• They are provided with the related base code orthosis; and

• The base orthosis is reasonable and necessary; and

• The addition is reasonable and necessary.

Addition codes will be denied as not reasonable and necessary if the base orthosis is not reasonable and necessary or the addition is not reasonable and necessary.

The following table lists addition codes which describe components or features that can be physically incorporated in the specified prefabricated base orthosis but are considered not reasonable and necessary. These addition codes, if they are billed with the related base code, will be denied as not reasonable and necessary.

Refer to the related Policy Article for information on addition codes that are considered not separately payable or incompatible with prefabricated knee orthosis base codes.


CUSTOM FABRICATED KNEE ORTHOSES (L1834, L1840, L1844, L1846, L1860):

A custom fabricated orthosis is covered when there is a documented physical characteristic which requires the use of a custom fabricated orthosis instead of a prefabricated orthosis. Examples of situations which meet the criterion for a custom fabricated orthosis include, but are not limited to:

1. Deformity of the leg or knee;

2. Size of thigh and calf;

3. Minimal muscle mass upon which to suspend an orthosis.

Although these are examples of potential situations where a custom fabricated orthosis may be appropriate, suppliers must consider prefabricated alternatives such as pediatric knee orthoses in beneficiaries with small limbs, straps with additional length for large limbs, etc.

If a custom fabricated orthosis is provided but the medical record does not document why that item is medically necessary instead of a prefabricated orthosis, the custom fabricated orthosis will be denied as not reasonable and necessary.

Custom fabricated orthoses (L1834, L1840, L1844, L1846, L1860) are not reasonable and necessary in the treatment of knee contractures in cases where the beneficiary is nonambulatory.

A custom fabricated knee immobilizer without joints (L1834) is covered if criteria 1 and 2 are met:

1. The coverage criteria for the prefabricated orthosis code L1830 are met; and

2. The general criterion defined above for a custom fabricated orthosis is met.

If an L1834 orthosis is provided and both criteria 1 and 2 are not met, the orthosis will be denied as not reasonable and necessary.

A custom fabricated derotation knee orthosis (L1840) is covered for instability due to internal ligamentous disruption of the knee (refer to the Group 3 ICD-10 Codes in the LCD-related Policy Article).

A custom fabricated knee orthosis with an adjustable flexion and extension joint (L1844, L1846) is covered if criteria 1 and 2 are met:

1. The coverage criteria for the prefabricated orthosis codes L1843, L1845, L1851 and L1852 are met; and

2. The general criterion defined above for a custom fabricated orthosis is met.

If an L1844 or L1846 orthosis is provided and both criteria 1 and 2 are not met the orthosis will be denied as not reasonable and necessary.

A custom fabricated knee orthosis with a modified supracondylar prosthetic socket (L1860) is covered for a beneficiary who is ambulatory and has knee instability due to genu recurvatum - hyperextended knee (refer to the Group 5 ICD-10 Codes in the LCD-related Policy Article).

The following table lists addition codes which describe components or features that can be and frequently are physically incorporated in the specified custom fabricated base orthosis. Addition codes may be separately payable if:

• They are provided with the related base code orthosis; and

• The base orthosis is reasonable and necessary; and

• The addition is reasonable and necessary.

Addition codes will be denied as not reasonable and necessary if the base orthosis is not reasonable and necessary or the addition is not reasonable and necessary.

The following table lists addition codes which describe components or features that can be physically incorporated in the specified custom fabricated base orthosis but are considered not reasonable and necessary. These addition codes, if they are billed with the related base code, will be denied as not reasonable and necessary.

Refer to the related Policy Article for information on addition codes that are considered not separately payable or incompatible with custom fabricated knee orthosis base codes.


MISCELLANEOUS:

Heavy duty knee joint codes (L2385, L2395) are covered only for beneficiaries who weigh more than 300 pounds.

Coverage of a removable soft interface (K0672) is limited to a maximum of two (2) per year beginning one (1) year after the date of service for initial issuance of the orthosis. Additional replacement interfaces will be denied as not reasonable and necessary. Refer to the Coding Guidelines section in the LCD related Policy Article for information on denial of removable soft interfaces that are billed separately at the time of initial issue of the orthosis.

Concentric adjustable torsion style mechanisms used to assist knee joint extension are coded as L2999 and are covered for beneficiaries who require knee extension assist in the absence of any co-existing joint contracture.

Concentric adjustable torsion style mechanisms used for the treatment of contractures, regardless of any co-existing condition(s), are coded as E1810, E1813, and/or E1814 and are covered under the Durable Medical Equipment benefit (refer to the CODING GUIDELINES section in the LCD-related Policy Article).

Claims for devices incorporating concentric adjustable torsion style mechanisms used for the treatment of any joint contracture and coded as L2999 will be denied as incorrect coding.

GENERAL

A Standard Written Order (SWO) must be communicated to the supplier before a claim is submitted. If the supplier bills for an item addressed in this policy without first receiving a completed SWO, the claim shall be denied as not reasonable and necessary.

For Durable Medical Equipment, Prosthetics, Orthotics and Supplies (DMEPOS) base items that require a Written Order Prior to Delivery (WOPD), the supplier must have received a signed SWO before the DMEPOS item is delivered to a beneficiary. If a supplier delivers a DMEPOS item without first receiving a WOPD, the claim shall be denied as not reasonable and necessary. Refer to the LCD-related Policy Article, located at the bottom of this policy under the Related Local Coverage Documents section.

For DMEPOS base items that require a WOPD, and also require separately billed associated options, accessories, and/or supplies, the supplier must have received a WOPD which lists the base item and which may list all the associated options, accessories, and/or supplies that are separately billed prior to the delivery of the items. In this scenario, if the supplier separately bills for associated options, accessories, and/or supplies without first receiving a completed and signed WOPD of the base item prior to delivery, the claim(s) shall be denied as not reasonable and necessary.

An item/service is correctly coded when it meets all the coding guidelines listed in CMS HCPCS guidelines, LCDs, LCD-related Policy Articles, or DME MAC articles. Claims that do not meet coding guidelines shall be denied as not reasonable and necessary/incorrectly coded.

Proof of delivery (POD) is a Supplier Standard and DMEPOS suppliers are required to maintain POD documentation in their files. Proof of delivery documentation must be made available to the Medicare contractor upon request. All services that do not have appropriate proof of delivery from the supplier shall be denied as not reasonable and necessary.

Clinical Background

Osteoarthritis (OA) is the most common form of arthritis and is a leading cause of disability.^1-4 The tibiofemoral joint is most often affected by OA, and within the knee joint, the medial compartment is the most frequently involved due to the mechanics and loading forces of ambulation.^5-10 The prevalence of knee osteoarthritis has increased in recent decades.¹¹ Using data from the National Health Interview Survey (NHIS),¹² it was estimated that 13.7 million people in the United States had symptomatic knee OA in 2007-2008, corresponding to 6.9% of the total US population ≥ 25 years of age. In 2011-2012, this estimate increased to 15.1 million, corresponding to 7.3% of the total US population ≥ 25 years of age.⁷ The prevalence of knee OA increases with each decade of life, with an estimated 16% of the adult population > 65 years of age experiencing symptomatic knee OA.⁷

Osteoarthritis of the knee can affect all structures within the joint, including the cartilage, synovium, ligaments, and bone.^4,13 Unicompartmental knee OA occurs when degenerative joint changes affect one part (e.g., the medial or lateral compartment) of the knee. Signs and symptoms of OA can include pain, stiffness, decreased range of motion, swelling and perceived instability.^2,4,7,14 Varus or valgus knee malalignment increases the risk of medial or lateral knee OA progression, respectively, and unicompartmental knee OA may lead to worsening of varus or valgus malalignment.^15-18 Additionally, an increase in varus-valgus laxity has been observed in patients with knee OA compared to individuals without knee OA.¹⁹ The presence of knee laxity may represent a risk factor for the development of knee OA, and may also influence disease progression;^19-21 however, a correlation between knee laxity and self-reported joint function has not been consistently identified.^8,22-25

Recommended nonsurgical management options for knee OA include, but are not limited to, exercise programs, weight loss, self-management programs, topical or oral nonsteroidal anti-inflammatory drugs (NSAIDs), intra-articular corticosteroids, and orthotics.^26-31 Several types of knee orthotics are available for the management of knee OA symptoms (e.g., compression sleeves, supportive braces, and unloader braces). Unloader, also known as offloader, knee braces use adjustable straps, condylar pads, or pneumatic bladders to apply either a valgus or varus external force on the knee joint for the management of medial or lateral unicompartmental OA, respectively. The therapeutic goal of an unloader knee brace is to reduce biomechanical forces on the degenerative compartment, realign the knee, and potentially relieve pain and improve function.^16,32,33

Currently, unloader knee braces are covered for Medicare beneficiaries with knee OA who are ambulatory and have objectively documented knee joint laxity. The aim of this summary of evidence is to determine if the use of unloader knee braces by Medicare beneficiaries with a diagnosis of medial or lateral unicompartmental knee OA, regardless of the presence of objective knee joint laxity, improves knee pain, mobility and/or function, or reduces the need for pain medication, delays disease progression, or improves quality of life (QoL).

Food and Drug Administration (FDA) Approval

Knee orthoses (braces) are classified as Class I (general controls) devices under 21 CFR 890.3475 (limb orthoses) and are exempt from 510(k) pre-market notification requirements.

Evidence Questions

The development of an assessment in support of Medicare coverage decisions is based on the same general question for almost all requests: “Is the evidence sufficient to conclude that the application of the technology under study will improve final health outcomes for Medicare patients?”

The formulation of specific questions for the assessment recognizes that the effect of an intervention can depend substantially on how it is delivered, to whom it is applied, the alternatives with which it is being compared, and the setting where it is used. In order to appraise the net health outcomes of unloading knee orthoses (i.e., braces) the DME MACs sought to address the following questions:

1. In Medicare Beneficiaries with a diagnosis of medial or lateral unicompartmental knee osteoarthritis, do "unloader" (offloading) knee braces compared to baseline (no brace), sham, or standard of care (SOC) reduce pain?

2. In Medicare Beneficiaries with a diagnosis of medial or lateral unicompartmental knee osteoarthritis, do "unloader" (offloading) knee braces compared to baseline (no brace), sham, or SOC decrease the use of pain medication (analgesics, opioids, intra-articular injections, etc.)?

3. In Medicare Beneficiaries with a diagnosis of medial or lateral unicompartmental knee osteoarthritis, do "unloader" (offloading) knee braces compared to baseline (no brace), sham, or SOC improve mobility?

4. In Medicare Beneficiaries with a diagnosis of knee medial or lateral unicompartmental osteoarthritis, do "unloader" (offloading) knee braces compared to baseline (no brace), sham, or SOC improve QoL?

5. In Medicare Beneficiaries with a diagnosis of medial or lateral unicompartmental knee osteoarthritis, do "unloader" (offloading) knee braces compared to baseline (no brace), sham, or SOC delay the progression of the disease and/or the need for surgical intervention?

Outcome Measures

A variety of objective and patient-reported outcome measures for knee OA have been used in clinical trials to evaluate the impact of the disease on outcomes such as pain, mobility and function, and quality of life. The following is a description of the outcome measures used in the studies reviewed for this analysis:

Objective Outcome Measures

2 Minute Walk Test (2MWT): Assesses mobility by having a participant walk at a self-selected pace for 2 minutes and measuring the distance walked; longer distance equals better function. This test was used by Cherian 2015³⁴ (modified by instructing participants to walk at the fastest speed possible), Mont 2015,³⁵ and Yu 2016.³⁶

6 Minute Walk Test (6MWT): Similar to the 2MWT, the 6MWT assesses mobility by having a participant walk at a self-selected pace for 6 minutes and measuring the distance walked; longer distance equals better function. This test was used by Madara 2019,³⁷ van Egmond 2017,³⁸ and Yu 2016.³⁶

Chair Rise Test: A functional outcome measure, used by Cherian 2015³⁴ and Mont 2015,³⁵ and described by Cherian 2015³⁴ as having participants repeatedly rise from a chair and return to a seated position, without using their arms, 5 times; shorter times equal better function.

Single Limb Step Test: A functional outcome measure, used by Cherian 2015³⁴ and Mont 2015,³⁵ and described by Cherian 2015 as the time it took a participant to step up to a six-inch platform 20 times; shorter times equal better function.

Stair Climb Test: A functional outcome measure, where participants are instructed to walk up and down a flight of stairs (Cherian 2015³⁴ specified 15 stairs, while Mont 2015³⁵ cited a reference which used 8-10 stairs); shorter times equal better function. Madara 2019³⁷ used a similar test, where participants were instructed to ascend and descend a flight of stairs as quickly as possible; lower times equal better function.

Timed-Up-And-Go Test (TUG): A functional outcome measure where participants rise from a chair, walk 3 meters, and then turn to walk back and sit down; shorter time equals better function.³⁹ This test was used by Yu 2016,³⁶ Cherian 2015,³⁴ and Mont 2015.³⁵

Subjective (Patient-reported) Outcome Measures

12-Item Short Form Survey (SF-12): A physical and mental health survey; higher scores equal better health (i.e., a score below 50 is “below average heath” and above 50 is “above average health”).⁴⁰ This was utilized by van Egmond 2017.³⁸

36-Item Short Form Survey (SF-36): A physical and mental health survey; higher scores equal better health (i.e., a score below 50 is “below average heath” and above 50 is “above average health”).⁴¹ This was used by Cherian 2015³⁴ and Mont 2015.³⁵

Assessment of Quality-of-Life Instrument (AQoL 6-D): A QoL scale where higher scores equal better QoL (i.e., the scale ranges from "-0.04 = lowest quality of life" to "1.00 = best quality of life").⁴² This was used by Hall 2022.⁴³

Clinical Global Impression of Improvement (CGI-I): Assesses a patient’s overall clinical condition; lower scores equal better improvement (i.e., terminal descriptors of “1 = very much improved” to “7 = very much worse since the initiation of treatment”).⁴⁴ There was 1 study which utilized this outcome, however, it was described differently than in the literature (Thoumie 2018⁴⁵ used a 5-point CGI-I Scale, stopping at “5 = minimally worse”).

EuroQOL Five Dimension – Three-Level (EQ-5D-3L): Consists of a VAS for health and 5 descriptive statistics on mobility, self-care, usual activities, pain/discomfort, and anxiety/depression which are rated from 1 “no problems” to 3 “extreme problems.”⁴⁶ Data can be presented as descriptive, (i.e., the number of participants reporting each level), as the standard VAS, or as a summary index, which applies a formula to apply a weight to each of the descriptive values (0 = worst health and 1 = perfect health). This scale was used by Lee 2017.⁴⁷

Global Rating Scale: Similar to a numerical rating scale, used and described by Hall 2022⁴³ as a 7-point scale (with terminal descriptions of “much worse” to “much better”) to assess overall change, as well as change in pain and function; scores were not calculated, instead the number of participants who reported either “moderately better” or “much better” were considered “improved.”

Knee injury and Osteoarthritis Outcome Score questionnaire (KOOS): An overall health outcome measure which consists of 5 domains to assess pain, symptoms, ADLs, function in sports and recreation, and QoL; higher scores equal better pain/function (i.e., scored 0 to 100, with 100 representing no problems).^48,49 The KOOS was used to assess pain (Hall 2022,⁴³ Gueugnon 2021,⁵⁰ Hjartarson 2018,⁵¹ Ostrander 2016,⁵² Yu 2016,³⁶ and Ornetti 2015⁵³), mobility (Beck 2023,⁵⁴ Hall 2022,⁴³ Gueugnon 2021,⁵⁰ Hjartarson 2018,⁵¹ Ostrander 2016,⁵² and Ornetti 2015⁵³), and QoL (Hall 2022,⁴³ Hjartarson 2018,⁵¹ Ostrander 2016,⁵² and Ornetti 2015⁵³).

Knee Outcome Survey – ADL scale (KOS): Assesses performance of functional ADLs and symptoms; higher scores equal better ADL performance/lack of symptoms (i.e., ADLs are scored as 0 “prevented from performing” to 5 “not affected”; symptoms are scored from 0 “the symptom prevents me from all daily activity” to 5 “I have never had the symptom”).⁵⁵ The KOS was used by Madara 2019³⁷ to assess mobility.

Knee Society Score (KSS): A health outcome measure consisting of 5 components for (1) patient demographics, (2) an objective knee score (completed by the surgeon; includes pain scales where higher scores equal greater pain), (3) patient expectations (higher score equals higher expectations), (4) a patient satisfaction score (higher score equals higher satisfaction), and (5) a functional knee score (maximum score of 100; includes ADLS, sports, and recreational activities; higher points indicate a greater functional level).⁵⁶ Three (3) studies used the KSS to assess pain (Larsen 2013,⁵⁷ Mont 2015,³⁵ and Hjartarson 2018⁵¹), while 2 studies used the KSS to assess mobility (Cherian 2015³⁴ and Mont 2015³⁵).

Lower-Extremity Activity Scale (LEAS): A self-reported functional measure; higher scores indicate a higher functional level.⁵⁸ Larsen 2013⁵⁷ used the LEAS to assess mobility.

Lower Extremity Functional Scale (LEFS): A self-reported functional measure; higher scores indicate a higher functional level.^59,60 Cherian 2015³⁴ and Mont 2015³⁵ used the LEFS to assess mobility.

Lequesne Scale: Assesses pain, walking distance, and performance of ADLs; lower scores equal better pain/function. Pain is rated on a 0-1 or 0-2 scale, as applicable, for each of 5 scenarios; walking distance is rated on a 7-point scale graded from "0 = unlimited" to "6 = less than 100 meters”, with additional points added for walking with a stick or crutch; and, ease of performing ADLs are rated as a 0 “easily”, a 1 “with difficulty”, or a 2 “impossible.”^61,62 There were 2 studies which utilized the Lequesne scale (Thoumie 2018⁴⁵ and Niazi 2013⁶³).

Numerical Rating Scale: A numerical rating scale consists of a set number of points (often 11 points), with terminal descriptors of “0 = no pain” and “10 = worse pain” (note: pain can be switched out for other outcomes of interest); a lower score typically equals better pain, unless the terminal descriptions are flipped.⁶⁴ A numerical rating scale was used by Madara 2019³⁷ and Hall 2022⁴³ to assess pain.

Osteoarthritis Knee-and-Hip Quality-of-Life questionnaire (OAKHQOL): Assesses QoL with 5 domains for physical activities, mental health, pain, social support, social functioning; higher scores equal better QoL on a scale from 0 to 100.^65-67 Gueugnon 2021⁵⁰ used the OAKHQOL for pain, mobility, and QoL.

Patient Global Impression of Change (PGIC): Assesses a patient’s impression of their improvement in condition after treatment; lower scores equal better improvement. There was 1 study which used this outcome, Thoumie 2018⁴⁵ used terminal descriptors of “1 = a great deal better” to “7 = no change or worse” and did not cite where this terminology came from, while literature on the PGI-C uses terminal descriptions of “much better” and “much worse” with “no change” in the middle of the scale.⁴⁴

Patient Specific Functional Scale (PSFS): Assesses patient function; higher scores equal greater function. Participants identify 5 important activities that they are either unable to perform or that are difficult to perform and rate this activity on a scale of 0 “unable to perform activity” to 10 “able to perform activity at pre-injury level.”⁶⁸ Madara 2019³⁷ used this scale only at baseline to characterize their study cohort.

Visual Analogue Scale (VAS): A VAS was primarily used to assess pain in the present studies; a VAS is a single line with terminal descriptions of “no pain” and “worst pain” and participants mark on the line their current pain level, the terminal descriptors are generally oriented so that lower scores equal better/less pain.⁶⁴ Studies which used a VAS to assess pain included Beck 2023,⁵⁴ Gueugnon 2021,⁵⁰ Thoumie 2018,⁴⁵ van Egmond 2017,³⁸ Yu 2016,³⁶ Cherian 2015,³⁴ Mont 2015,³⁵ Fu 2015,⁶⁹ Ornetti 2015,⁵³ Jones 2013,⁷⁰ and Naizi 2013;⁶³ an additional study, Ostrander 2016⁵² used a VAS to assess activity.

Western Ontario and McMaster Universities Arthritis Index (WOMAC): Includes a total score, as well as domains which evaluate pain, function, and stiffness; higher scores equal worse pain/function. Can be administered as either a Likert Scale or a Visual Analogue Scale.⁷¹ There were 5 studies which utilized the WOMAC, 2 studies used it as intended (Fu 2015⁶⁹ and Jones 2013⁷⁰), 1 study used it as part of their SRMA (Moyer 2015⁷²), and 2 studies used the WOMAC differently than originally described (Haladik 2014⁷³ described a higher score as indicating better pain/function; van Egmond 2017³⁸ described the WOMAC as intended, with higher scores equaling worse pain/function, but then asserted that scores which increased after brace use indicated improvement in clinical parameters).

Clinically Meaningful Effect

Some clinical trials included in this analysis report the minimally important change (MIC; within a treatment group or individual) or minimally important difference (MID; between treatment groups) for patient-reported outcome measures. The MIC and MID can aid in determining whether a statistically significant difference found in a trial translates to a clinically meaningful improvement for patients.^74-77 However, for knee OA, MICs and MIDs are context-specific and can vary greatly based on calculation method, study design, patient population, intervention, disease severity, and duration of follow-up.^75,78-81 For example, when the same patient-reported outcome measure is used to assess improvement for a high-risk (e.g. total knee replacement) compared to a low-risk (e.g., exercise program) intervention, it would be reasonable for the MIC or MID to be larger for the higher-risk intervention (i.e., a higher risk intervention would be expected to provide a greater improvement in the patient-reported outcome measure). Similarly, patients suffering from greater symptom severity may require a larger change in symptoms after an intervention for the effect to be considered meaningful compared to a patient with less severe symptoms.⁷⁵ Importantly, values relevant to knee OA within the context of a specific treatment modality may not be generalizable to other options (surgical or device) used to treat knee OA.⁷⁸ There is continued discussion regarding the use of MICs and MIDs in clinical research, with some authors noting the use of a general range of estimates being one potential approach to managing the wide variability in MIC and MID values calculated across studies.^75,81 For these reasons, absolute values for MIC or MID for knee OA measurement instruments have not been included, but will be reported in this analysis when published by the study authors in the individual clinical trial.

Clinical Literature Analysis

In a survey based study by Dries, et al.,⁸² including 381 patients (mean age: 64.9; 60% female) with knee OA, evaluated the perception-based effects of two unloader knee braces on mobility and pain after 3 weeks of use compared to no brace. For mobility, there was a 74% reduction in the number of participants reporting mobility limited to the home (i.e., 0 to 10 meters), a 62% reduction in the number of participants reporting the two lowest mobility classes (i.e., 0 to 10 meters, 10 to 50 meters), and an 82% increase in the number of participants reporting the two highest mobility classes (i.e., 1000 to 5000 meters, > 5 kilometers). For pain, 54% of participants reported an improvement in pain symptoms; specifically, 29% of responders reported a "significant" or "very significant" reduction in pain, while 36% reported no change and 10% reported a deterioration (i.e., increase in pain). Finally, for daily functioning, 62% of patients reported an improvement; specifically, 29% reported significant improvement, 7% reported very significant improvement, 29% reported no change, and 9% reported a deterioration in daily functioning. Limitations of the study included its observational design which lacked a control group, the use of a patient-reported survey which are potentially subject to recall and response bias, and the lack of a baseline questionnaire and assessment of potential confounders (i.e., analgesics use).

A prospective, case series study by Niazi, et al.,⁶³ including 80 patients (mean age: 48 ± 8.93; 60% female) with medial compartment knee OA [Kellgren & Lawrence (KL) grades II-IV], analyzed the effects of a custom made 3-point varus brace on pain severity (measured via a VAS and analgesic usage) and mobility (measured by walk distance on the Lequesne scale) after 9 months of treatment compared to baseline. There was a statistically significant improvement in mean VAS pain score, mean walking distance on the Lequesne scale, and mean number of pain killers used (all p = 0.001). Limitations of this study include its observational design which lacked a control group, a small sample size, the short duration of follow-up, and the lack of a sensitivity analysis examining the impact of analgesic use on the outcomes.

A cohort study by Haladik, et al.,⁷³ including 10 patients (mean age: 59.5 ± 7.3; 90% male) with medial compartment knee OA, analyzed the effects of an unloader brace on pain and function as measured by the WOMAC after 2 weeks of treatment compared to baseline. There was a statistically significant improvement in the WOMAC total score (% improvement: 33 ± 39; p = 0.01), as well as in the WOMAC subscales of pain (% improvement: 41.3 ± 42.5; p = 0.01) and function (% improvement: 33.0 ± 43.9; p = 0.01). No statistically significant difference was reported in the WOMAC stiffness subscale. Limitations of this study include the observational design which lacked blinding and a control group, a small sample size, the short duration of follow-up, and the reliance on patient reported outcomes which are potentially subject to response and recall bias.

A cohort study by Beck, et al.,⁵⁴ enrolling 15 patients (14 completed the study; mean age: 43.1 ± 9.4; 50% male) with unicompartmental knee OA, analyzed the effect of an unloader brace on pain (measured by a VAS pain score) and function (measured by the KOOS) after 3 months of wear. Participants kept a diary to monitor compliance with brace use and changes in VAS pain score. On average, participants wore the brace for 8.2 hours per day and braced for a mean of 14.4 ± 2.0 weeks. After 3 months of bracing compared to baseline, there was a statistically significant improvement in knee function and pain (both p < 0.001). Limitations of this study included the observational design which lacked blinding and a control group, a small sample size, the short duration of follow-up, and the reliance on patient reported outcomes which are potentially subject to response and recall bias.

A prospective, single-center, cohort study by Larsen, et al.,⁵⁷ enrolling 23 patients (mean age: 63.7 ± 10.6 years) with medial knee OA (KL grades I-IV), investigated the effects of a custom valgus brace on activity (measured by the LEAS) and pain (measured by the pain component of the KSS) over 2 months of use compared to baseline. There were no statistically significant changes in KSS score (i.e., pain) at 1- or 2-months compared to baseline. In participants with KL I-II OA, LEAS scores for participants were not statistically improved at 1-month; however, there was a statistically significant improvement at 2-months (p = 0.033). For participants with KL III-IV OA, LEAS scores improved with statistical significance at 1-month (p = 0.033); however, at 2-months, the average LEAS score decreased and was no longer statistically different compared to baseline. Limitations of this study include the observational design which lacked blinding and a control group, lack of control for confounders (e.g., use of analgesics), the small sample size, the short duration of follow-up, and the use of patient reported outcomes which are potentially subject to response and recall bias.

A randomized cross-over study by Jones, et al.,⁷⁰ including 28 patients (mean age: 66.3; 57.1% male) with medial compartment knee OA (KL grades II-III), analyzed the effects of a valgus knee brace compared to a lateral wedge insole on walking speed, and function and pain (measured by the WOMAC) after 14 days of treatment per intervention; a patient diary was used to record daily use, as well as comfort and pain (measured with a VAS). Compared to baseline, the use of a valgus knee brace or lateral wedged insole was associated with a statistically significant improvement in the WOMAC subscales for pain and function (brace pain: p = 0.002; brace function: p = 0.005), walking speed (brace p = 0.032) and VAS pain score (brace p = 0.001); however, the improvement in the WOMAC subscale for stiffness did not reach statistical significance. There were no statistically significant differences between the two interventions in any clinical outcomes. For usage and comfort, 71% of participants wore the valgus brace for less than 4 hours per day, while 71% of participants wore the lateral wedged insole for more than 4 hours per day; the lateral wedged insole was also reported to be significantly more comfortable than the valgus brace (p = 0.001). Limitations of this study include the lack of blinding of participants and assessors, the small sample size, and the short duration of follow-up.

A retrospective study by Lee, et al.⁴⁷ analyzed 8 years of follow-up data from 63 patients (mean age: 50.9; 58.7% female; mean BMI: 28.6) with end-stage unicompartmental (lateral or medial) knee OA on a waitlist for surgery to determine the effects of unloading knee braces on the occurrence of surgical intervention, quality of life (QoL; measured by the EQ-5D-3L), and quality-adjusted life years (QALYs). Participants wore the brace for a mean duration (SD) of 26.1 (31.6) months; 40.5% ceased brace use within 6 months of beginning brace treatment. After 24 months, 25.4% of participants continued to wear the brace; these participants were significantly less likely to undergo surgery. Participants [38/63 (60.3%)] who underwent surgery wore the brace for an average of 8 months. Participants who wore the brace for 6 months were more likely to avoid surgery than those who wore the brace for 3 months (8.4% vs 4.1%). All participants, regardless of duration of brace wear, had an improvement in QoL with a mean gain (SD) of 0.435 (0.714) QALYs; the longer the brace was worn, the more QALYs were gained (1-6 months: 0.0631; 7-12 months: 0.176; 13-24 months: 0.268; ≥ 25 months: 1.292). At 2 years, the number of QALYs (95% CI) gained was similar between the unloader brace group [0.435 (0.255 to 0.615)] and comparator data from a study on total knee replacement [0.416 (0.252 to 0.581)].⁸³ For adverse events, 43% of participants reported a soft tissue issue with the brace that required technical support. Limitations of this study included the small sample size, unclear methodology of reporting compliance and adverse events, and the lack of controlling for confounders (e.g., analgesic use).

A study by Chughtai, et al.⁸⁴ utilizing a database of participants from a prospective randomized study, enrolling 40 patients [36 patients included in analysis; brace plus SOC: n = 11, mean age 55 years, 55% male, mean BMI 30; SOC only group: n = 25, mean age 63 years, mean BMI 33] with late-stage knee OA (KL grades III-IV), assessed the effect of a pneumatic unloader knee brace on the rate of total knee arthroplasty (TKA), opioid use, and the use of pain relieving injections compared to SOC over a mean follow-up time of 27 months. During the study time, 18% utilizing a database of participants from a prospective randomized study, enrolling 40 patients [36 patients included in analysis; brace plus SOC: n = 11, mean age 55 years, 55% male, mean BMI 30; SOC only group: n = 25, mean age 63 years, mean BMI 33] with late-stage knee OA (KL grades III-IV), assessed the effect of a pneumatic unloader knee brace on the rate of total knee arthroplasty (TKA), opioid use, and the use of pain relieving injections compared to SOC over a mean follow-up time of 27 months. During the study time, 18% (n = 2) of the brace cohort and 36% (n = 9) of the SOC cohort underwent a TKA (p = 0.285); the time from enrollment to TKA was not significantly different between groups. Opioid use was similar in the two treatment groups; however, there was a significant difference in the proportion of patients who had an intra-articular injection [brace cohort: 46% (n = 5); control cohort: 83% (n = 19); p = 0.026]. No major adverse events were reported. Limitations of this study include the small cohort size and uneven distribution of participants between the study cohorts.

A randomized study by Hjartarson, et al.,⁵¹ enrolling 150 patients (149 completed baseline questionnaires) with mild to moderate knee OA (Allbäck or KL grade I-II), analyzed the effect of an unloader knee brace (n = 74, mean age: 59.8 years, 37% female) compared to a placebo (n = 75, mean age: 60.3, 44% female) on function (measured by the KSS) and overall health outcomes (measured by the KOOS) over a one year period. After 12 months, there was a statistically significant difference between the treatment groups in the average total KSS score (p = 0.009). For the KSS functional score, both the study and control groups were improved at 52 weeks [67.0 (95% CI: 64.0–70.1) to 78.6 (95% CI: 74.7–82.5) and 67.1 (95% CI 64.0–70.3) to 70.8 (95% CI 66.2–75.3), respectively]. For the KOOS subscales, compared to baseline, the active brace group had a statistically and clinically significant improvement in the KOOS sports and recreation subscale (score difference: 15.7; p < 0.001), and statistically significant improvements in the ADL (score difference: 9.8; p < 0.001) and symptoms (score difference: 7.9; p < 0.001) subscales. When the active brace group was compared to the control group, there was a statistically and clinically significant difference in the KOOS sports and recreation subscale (score difference: 12.5; p < 0.001), and statistically significant differences in the pain (score difference: 5.2; p = 0.02) and QoL (score difference: 6.1; p = 0.02) subscales, favoring the active brace. There were no clinically important differences in the KOOS pain, symptoms, QoL, or ADL subscales for the active treatment group compared to baseline or between treatment groups at 12-months. Limitations of the study included a high attrition rate, a difference in dropout rates between the study and control groups, and the use of a placebo that may have had some clinical effect or may have negatively affected the participants due to the high rate of mechanical issue dropouts from the control group.

A 1-year, open label, phase-3 RCT by Gueugnon, et al.,⁵⁰ including 120 participants (brace: mean age 65 ± 11.8, 56.7% female; SOC: mean age 62.2 ± 11.1, 56.7% female) with medial knee OA (KL grade II-IV), examined the effect of a custom-made, distraction-rotation knee brace in conjunction with standard of care on pain (measured by VAS and KOOS), mobility/function (measured by KOOS), and QoL (measured by KOOS and OAKHQOL) compared to standard of care alone. For VAS pain (MCID defined as a reduction of > 19.9)⁸⁵ compared to baseline, an ITT analysis (assumption of maximal bias) found a VAS score change of -10.4 (95% CI: -16.8 to -4.1) in the SOC group and a change of -17.3 (95% CI: -23.4 to -11.2) in the brace group, and an unadjusted PP analysis found a VAS score change of -9.4 (95% CI: -16.4 to -2.4) in the SOC group and a change of -21.2 (95% CI: -28.2 to -14.1) in the brace group. For VAS pain, significantly more participants in the brace group, compared to the SOC group, met the MCID [adjusted odds ratio (OR) = 2.76, 95% CI: 1.05–7.23; p = 0.04] and the patient-acceptable symptomatic state [defined as a score of < 30; OR = 2.97 (95% CI: 1.09–8.10); p = 0.03]. At 12 months, when compared to the control group, the brace group had significantly greater improvement in the KOOS subscales for pain (8.8, 95% CI: 1.4–16.2; p = 0.02), other symptoms (10.4, 95% CI: 2.7–18; p = 0.0009), ADLs (9.2, 95% CI: 1.1–17.2; p = 0.027), function in sport and leisure (12.3, 95% CI: 4.3–20.3; p = 0.003), and QoL (9.9, 95% CI: 0.9–15.9; p = 0.031). There were also significantly greater improvements in the OAKHQOL domains of physical activities (8.2, 95% CI: 0.6–15.8; p = 0.034) and pain (14.8, 95% CI: 5–24.6; p = 0.003), but not in the OAKHQOL domains of mental health, social activities, or social support in the brace group compared to the SOC group at 12-months. The brace group was significantly more likely to reach the MCID for the KOOS ADL subscale (OR = 4.90, 95% CI: 1.68–14.32; p = 0.004), and the OAKHQOL domains of physical activity (OR = 4.43, 95% CI: 1.38–14.21; p = 0.01), pain (OR = 3.56, 95% CI: 1.20–10.56; p = 0.02), and mental health (OR = 2.91, 95% CI: 1.04–8.12; p = 0.04). There were no statistically significant differences in the use of analgesics, NSAIDs, hyaluronic acid or steroid injections, or non-pharmacological treatments between the treatment groups. There was one (1) serious AE in both the treatment and control group of deep vein thrombosis, which was considered potentially related to the intervention in the brace group. Limitations of this study included the lack of blinding, and a statistically significant between group difference in demographic characteristics despite randomization (i.e., higher VAS pain, more frequent history of knee surgery and lower incidence of other osteo-articular disease in the treatment knee, and lower level of education in the brace group compared to SOC group).

A prospective, randomized study by Ostrander, et al.,⁵² enrolling 50 patients (31 completed the study; brace: n = 16, mean age 63.1, 50% male; SOC: n = 15, mean age 66.8, 53% male), analyzed the efficacy of an unloader knee brace on pain, function, and QoL (measured by the KOOS) compared to standard of care (i.e., NSAID use, home exercise, and joint supplements). A weekly diary was also maintained by participants to record a VAS pain scale, activity level, NSAID use, and sleep quality. Participants in the brace group, on average, wore the brace 6.7 hours per day. Compared to the SOC group, there were statistically significant improvements in the brace group in the KOOS overall total score (brace CI: 56.2-64.0; control CI: 47.9-55.8; p = 0.004), as well as in the KOOS subscales of pain (brace CI: 59.5-66.9; SOC CI: 49.2-56.8; p < 0.001), symptoms (brace CI: 58.0-66.2; SOC CI: 52.5-61.0; p = 0.007), and ADLs (brace CI: 64.2-72.6; SOC CI: 55.8-64.5; p = 0.008). There were no differences between the groups in the KOOS subscales of QoL or sports and recreation function. Based on diary entries, there were statistically significant improvements in VAS pain (p = 0.021) and activity levels (p = 0.035); however, there were no significant differences in NSAID use or ability to sleep in the brace group compared to the SOC group. Limitations of this study include the small sample size (the calculated target of 30 patients per group was not reached), and potential heterogeneity in the standard of care.

A multicenter, prospective, open-label RCT by Thoumie, et al.,⁴⁵ enrolling 67 patients (brace group: n = 32, mean age 64.8, 75% women; usual care group: n = 35, mean age 66.6, 57% women; 60 completed the study) with medial knee OA (KL II-IV), assessed the effect of an unloading knee brace in addition to usual care on global knee pain (defined as pain over the last 24-hours) and pain on motion (both measured by a 100-mm VAS), functional disability (measured by the Lequesne index), evolution of disease (measured by the PGIC and CGI-I), responder rate to treatment [determined by the Osteoarthritis Research Society International (OARSI)-Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) criteria], analgesic consumption, and safety/acceptability compared to usual care alone after 6 weeks of treatment. There was a statistically significant decrease in VAS global knee pain in both treatment groups compared to baseline [mean (SD); brace: 63.8 (10.6) to 22.2 (19.9); usual care: 64.7 (13.5) to 49.0 (23.4)]; a statistically significant between-group difference was also found starting at 2-weeks of treatment [mean difference: −26.7 (95% CI −35.0 to −18.5); p < 0.001], which continued through 6 weeks [−26.0 mm (95% CI: −41.6 to −10.3); p < 0.0001]. There were also statistically significant between-group differences in improvement in pain on motion [−33.0 mm (95% CI: −42.7 to −23.2); p < 0.001] and functional disability [−3.4 (95% CI: −4.9 to −2.0); p < 0.001]. At 6 weeks, investigators, using the CGI-I, reported “much” to “very much” improvement for most patients in the brace group (82.1%), while they reported “no change” or “worsening” in most patients in the control group (53.2%); similarly, using the PGIC, 86.2% of the brace group reported feeling “better” to “a great deal better,” while 43.8% of participants in the usual care group reported “almost the same” or “no change.” The responder rate was also significantly higher in the brace group compared to the control group per the OARSI-OMERACT criteria (72.4% and 34.4%, respectively; p < 0.001). Limitations of this study included the open label design and lack of a sham device, small sample size, short duration of follow-up, reporting of percentages for the PGIC and CGI-I that are not direct comparisons between the brace and control groups, lack of controlling for confounding (e.g., analgesics use), and early study enrollment termination (due to an initially unplanned interim analysis showing superiority of the unloading knee brace combined with usual care).

An observational longitudinal cohort study by Hall, et al.,⁴³ enrolling 30 patients (mean age: 61.4; 60% male; 28 completed the study) with medial tibiofemoral knee OA (KL grade II-IV), evaluated the effect of a valgus unloader knee brace on pain (measured by an 11-point numerical rating scale and the KOOS), knee related problems (measured by the KOOS), and QoL (measured by the KOOS and AQoL 6-D) compared to baseline, as well as confidence, adherence and acceptability of brace treatment (all measured by an 11-point numerical rating scale), and AEs over 8-weeks. Additionally, pain, function, and overall symptoms were measured with a 7-point global rating scale. Compared to baseline, for pain during walking, there was a mean difference of -3.3 (95% CI: -4.1 to 2.6) with 25 (89%) participants meeting or exceeding the MCID; for the KOOS, the majority of patients met the MCID on the subscales for pain [n = 22 (76%)], function [n = 22 (76%)], sport and recreation [n = 22 (76%)], and QoL [n = 17 (59%)]. Additionally, 15 (52%) participants met the MCID for the AQoL 6-D. On the 7-point global rating scales, 18 (64%) participants reported “moderately better” or “much better” for their pain and 15 (54%) reported “moderately better” or “much better” for both their physical function and overall symptoms. Participants reported a mean (SD) wear time of 6 (3) hours per day, a mean (SD) weekly confidence level while performing daily tasks with the brace of 8.7 (0.3), a mean (SD) adherence to instructions of 8.4 (0.2), and a mean (SD) weekly brace comfort level of 8.0 (0.5). There were 30 adverse events reported in 17 participants; skin irritation (11/30; 37%), increased knee pain in the study knee (5/30; 25%), contralateral knee/hip pain (3/30; 10%), and back pain or pain in another area (1/30 for each; 3% each). Limitations of this study included the observational design with lack of a control group, small sample size, and short duration of follow-up.

A prospective, double-armed RCT by van Egmond, et al.,³⁸ enrolling 100 patients (76 completed final follow-up) with knee OA (KL grade ≥ I, majority KL grade II or III), analyzed the effect of two valgus unloading braces (Bledsoe brace: n = 50, median age 55, 60% male; SofTec OA brace: n = 50, median age 57, 56% male) on pain and satisfaction (both measured by an 11-point VAS scale), clinical outcomes (measured by the WOMAC), QoL (measured by the SF-12), and mobility (measured by the 6MWT) over 12 weeks. Compared to baseline, there were statistically significant improvements in both brace groups in VAS satisfaction [mean difference (95% CI), Bledsoe: -1.3 (-2.4 to -0.1), p = 0.036; Softec: -1.4 (-2.6 to -0.3), p = 0.013], WOMAC overall score [Bledsoe: -9.9 (-14.7 to -5.0), p < 0.001; Softec: -8.9 (-14.4 to -3.4), p = 0.002], WOMAC pain subscale [Bledsoe: -1.9 (-3.0 to -0.7), p = 0.002; Softec: -1.6 (-3.2 to -0.1), p = 0.041], WOMAC stiffness subscale [Bledsoe: p = 0.006; Softec: -0.9 (-1.6 to -0.2), p = 0.010], the WOMAC ADL subscale [Bledsoe: -7.0 (-10.6 to -3.4), p < 0.001; Softec: -6.4 (-10.2 to -2.6), p = 0.002], and the SF-12 physical component summary [Bledsoe: -3.1 (-5.5 to -0.7), p = 0.013; Softec: -4.4 (-7.0 to -1.7), p = 0.002]. Only the Bledsoe brace group had statistically significant improvements in the 6MWT (p = 0.004) and VAS pain [mean difference (95% CI): 0.9 (0.2 to 1.6), p = 0.013] at the 12-week follow-up, compared to baseline. There were no significant differences in either brace group, compared to baseline, for the SF-12 mental component summary and analgesic use. There were no significant differences between brace groups for any outcome. No major adverse events were reported. Limitations of this study include the loss of 24% of participants (potential selection bias), short duration of follow-up, lack of blinding of patients and investigator (potential information bias), and lack of a non-braced control group.

A convenience sample cohort study by Yu, et al.,³⁶ enrolling 204 patients (109 completed the study) with medial tibiofemoral, lateral tibiofemoral, or patellofemoral OA (KL grade ≥ II and on the waitlist for joint replacement surgery), assessed the effect of an unloader brace (focus of analysis; n=86; mean age: 67.7; 37.2% male, median KL grade: III), patellofemoral brace (n = 50; mean age: 67.2; 27.4% male), or no brace (due to clinical presentation and lack of suitability; n = 68; mean age: 67.0; 30.1% male; median KL grade: IV) on pain (measured by a VAS and the KOOS pain subscale) and function (measured by the KOOS ADL subscale, 6MWT and TUG) over 52 weeks. All interventions were provided in addition to an individually tailored OA management program. Compared to baseline, there was a statistically significant improvement for both the unloader and no brace groups in the KOOS pain subscale [mean difference (95% CI); unloader brace: 7.55 (3.01 to 12.10), p = 0.002; no brace: 12.96 (4.39 to 21.5), p = 0.005], the KOOS ADL subscale [unloader brace: 6.75 (2.67 to 10.83), p = 0.002; no brace: 12.14 (4.13 to 20.17), p = 0.004], the 6MWT [unloader brace: 49.60 (21.12 to 78.08), p = 0.001; no brace: 52.0 (30.59 to 73.41, p < 0.001], the TUG [unloader: −2.73 (−3.67 to −1.80), p < 0.001; no brace: −1.81 (−2.77 to −0.85), p = 0.001], and the VAS pain score [unloader: −1.36 (−1.90 to −0.83), p = 0.001; no brace: −1.56 (−2.29 to −0.83), p < 0.001]. There were no significant differences between groups for any outcomes. For adherence, most participants reported 2-4 hours of use per day with 55.4% of unloader group participants using the brace daily. For adverse events, 32.7% of unloader group participants reported brace migration. Limitations of this study included the heterogeneity and significant baseline differences in the treatment group cohort (due to real-world study design), the unblinded and non-randomized nature of the study (especially in regard to response and recall bias in the patient-reported outcome measures), and the loss of 47% of participants by the week 52 follow-up.

An open-label, single center, prospective study by Ornetti, et al.,⁵³ including 20 patients (mean age: 64.2 ± 10.2 years; 80% female) with medial knee OA (KL grade ≥ II), evaluated the effectiveness and safety of a custom-made valgus knee brace on pain (measured at rest by a VAS), function (measured by the KOOS), use of NSAIDs and analgesics (evaluated as the number of days per week each class of drug was taken), and disease severity (measured by a semi-quantitative Likert scale) at 6-weeks (W6) and 1 year (W52). Spatio-temporal gait variables [including walking speed (m/s)] were collected at baseline (W0) and W6. At W6, the mean VAS pain score had decreased by more than 50% from baseline (p < 0.001); the mean pain score increased at W52 but remained significantly improved compared to baseline. There were statistically significant functional improvements at both W6 and W52 compared to baseline (all p < 0.05) for each of the KOOS domains (i.e., pain, other symptoms, ADLs, sports and leisure activities, and QoL). For the KOOS domains of pain, symptoms, and ADLs there was significant worsening noted between W6 and W52, but the domains remained significantly improved at W52 compared to baseline; improvement for QoL and ADLs was superior to the recognized MCID (defined as a change of scores of -8.0 and -9.0, respectively).^85,86 On the Likert scale, at W6, 85% of patients indicated their disease severity was ‘‘improved’’ or ‘‘much improved’’ compared with 76% reporting similar improvement at W52. The use of NSAIDs and analgesics decreased significantly at both W6 and W52 (both p < 0.05 compared to baseline). Walking speed increased by a mean of 10% (p < 0.05) and exceeded 1 m/s. Six patients reported a ≥ 1 superficial adverse effect on the skin and one participant had to stop participation in the study early due to aggravation of lower-limb varicose veins without any signs of deep vein thrombosis. Limitations of this study included the small sample size, the single center open-label design, and the lack of a comparator/sham device which may have led to a placebo effect.

A prospective, randomized pilot study by Mont, et al.,³⁵ enrolling 22 patients (18 completed the study) with knee OA (KL grades I-II), analyzed the effect of an unloader brace (n = 9; mean age: 60; 55.5% male) compared to standard of care [i.e., exercise, medication (NSAIDS or opioids), and/or cortisone injections; n =9; mean age: 56; 33.3% male] on pain (measured by a VAS), objective functional improvement (measured by the TUG, 5-repetition chair rise test, 2MWT, timed stair climb, single limb step test), subjective functional improvement [measured by the KSS (functional and objective) and LEFS], and QoL (measured by the SF-36) over 3 months of treatment. Except for a statistically significant difference in the mean change in the pre- and post-treatment KSS objective scores between study cohorts compared to baseline (brace mean change: 13; SOC mean change: 5.9; p = 0.032), there were no significant differences in the mean change in pain, objective or subjective function, or QoL between the two treatment groups compared to baseline. Limitations of this study included the small sample size, short duration of follow-up, lack of blinding, use of subjective outcome measures (potential for response and recall bias), and the lack of controlling for confounding (e.g., analysis of potential differences in baseline disease burden).

A randomized study by Madara, et al.,³⁷ enrolling 33 patients (30 completed the study per-protocol) with knee OA, evaluated the effectiveness of an unloader knee brace in combination with a stretching program (n = 13; mean age: 66.8; 54% male) compared to a stretching program alone (n = 17; mean age: 62.9; 41% male) on mobility (measured by the SCT and 6MWT), patient-reported function (measured by the KOS), and pain (measured by 3 separate 11-point numerical rating scales for average pain in the past week, pain at its worse, and pain at its best) after 6-weeks of treatment compared to baseline. There was a statistically significant interaction between 'time' (i.e., baseline compared to follow-up time) and 'group' (i.e., brace compared to control) for knee pain at its worst (p = 0.002; post-hoc analysis baseline vs. 6-week: brace group 7.3 vs. 4.7, p = 0.006; control group 6.3 vs. 6.4, p = 0.849). Regardless of treatment group assignment, there were statistically significant effects of time on the SCT (p = 0.02) and knee pain at its best (p = 0.050). There were no significant effects on average pain, the 6MWT, or KOS score based on time or group. Limitations of this study included the small sample size, short duration of follow-up, and unclear blinding of participants and assessors.

A prospective cohort study by Fu, et al.,⁶⁹ enrolling 18 patients (10 completed the study; mean age: 56; 60% female) with medial compartment knee OA (KL grade II-IV), analyzed the effect of different orthotic combinations (e.g., valgus knee brace, with or without lateral wedged insole) on pain (measured by VAS and the WOMAC) and function (measured by the WOMAC) after 4 weeks of treatment. Participants were sequentially treated with 6 different orthotic modalities for four weeks each (including a valgus knee brace, which will be the focus of this summary). After 4 weeks of brace treatment, participants reported a statistically significant improvement in the WOMAC pain subscale (% reduction: -20.4; p = 0.02), VAS pain score (% reduction: -15.5; p = 0.04), and numbers of days of analgesic use in a week (p = 0.04) compared to baseline. There were no significant differences in the WOMAC total score, or the WOMAC stiffness or ADL subscales. The valgus brace group had a compliance rate of 54.5% of total walking time, which was significantly lower than any of the insole groups; the only group with a lower compliance rate (49.1% of total walking time) was the combined valgus knee brace and lateral wedged insole with arch support group. Limitations of this study included the small sample size, high dropout rate, short duration of follow-up, poor compliance with bracing, and lack of blinding, randomization, or a control group.

A prospective RCT by Cherian, et al.,³⁴ enrolling 59 patients (52 were included in the final analysis) with late stage knee OA (KL grades III or IV), analyzed the effect of an unloader knee brace (n = 26; mean age: 59; 50% male) compared to SOC (n = 26; mean age: 54; 53.8% male) on functional improvements (measured by the KSS, LEFS, TUG, stair climb test, repeated chair rise test, single limb step test), pain (measured by a VAS), quality of life (measured by the SF-36), and delay in TKA after 3 months of treatment. For pain, there was statistically significant improvement in VAS pain score in the brace group compared to baseline (p = 0.00075) and to the SOC group (p = 0.0057). In objective functional outcomes, compared to baseline, the brace group had statistically significant improvements in the TUG (mean change: 2.4 sec; p = 0.007), the timed stair test (mean change: 7.8 sec; p = 0.0408), and the 2MWT (mean change: 43.3 feet; p = 0.019), but not in the repeated chair rise or the single limb step test; compared to the SOC group, the brace group had a statistically significant, greater improvement in the TUG, the stair climb test, and the 2MWT (p = 0.001-0.05). In subjective functional outcomes, compared to baseline, the brace group had statistically significant improvements in the LEFS (mean change: 8.3; p = 0.001) and the KSS objective score (mean change: 10.7; p = 0.0067), but not in the KSS functional score, or the SF-36 mental or physical scores; compared to the SOC group, the brace group had statistically significant greater improvements in the LEFS and the KSS objective score (p = 0.0089). The SOC group had no significant differences, compared to baseline, in scores in the pain VAS or any subjective or objective functional outcomes. A total of 7 patients (brace: n = 2; SOC: n = 5) elected to have a TKA; however, this study was not significantly powered to detect a short-term difference between the cohorts. No major adverse events were reported. Limitations of this study included the small sample size, short duration of follow-up, potential for confounding (variability in SOC available), and the use of subjective outcome measures which are potentially subject to response and recall bias.

Systematic Reviews and Meta-Analyses

A systematic review and meta-analysis by Moyer, et al.,⁷² evaluated the effect of valgus knee braces compared to no brace, SOC, neutral brace, neoprene sleeve, or shoe inserts on pain, function, safety, and compliance in patients with medial knee OA. A total of 8 RCTs were identified in the literature search; 6 RCTs were included in the meta-analysis,^70,87-91 while the remaining 2 RCTs were excluded due to one study providing insufficient pain and function data,⁹² and the second only comparing 2 types of valgus braces without a control.⁹³ There was a total population of 445 patients with knee OA (275 used a valgus brace; age range: 34 to 73; 55% male). Compared to the combined control treatment population, the use of a brace was associated with a small, but statistically significant improvement in pain [SMD 0.33 (95% CI: 0.13, 0.52), p = 0.001; I² = 0.0%] and function [SMD 0.22 (95% CI: 0.02, 0.41), p = 0.03; I² = 0.0%]. Compared to the SOC group alone, use of a brace was also associated with statistically significant improvements in pain [SMD 0.56 (95% CI: 0.03, 1.09), p = 0.04; I² = 68.1%] and function [SMD 0.48 (95% CI: 0.02, 0.95), p = 0.04; I² = 59.7%]. Finally, compared to the ‘other orthosis’ control group, the use of a brace was associated with similar improvements in pain [SMD 0.33 (95% CI: 0.08, 0.58), p = 0.01; I² = 14.0%], but not in function [SMD 0.19 (95% CI: -0.03, 0.42), p = 0.09; I² = 0.0%]. At the longest follow-up point, 2 parallel-group studies reported a compliance rate of 45-58%, while the 4 cross-over studies reported a compliance rate of 71-100%. Complications included poor fit, slipping, swelling, blisters, and skin irritation, with event rates ranging from 0.01 to 0.22. This systematic review is limited by the relatively low number of patients for a meta-analysis, the low or unclear quality of the included trials, the variability in brace design and in the choice of controls, the variability in dosing instructions across studies, and the inability to perform the a priori subgroup analysis for comparisons with high heterogeneity.

A systematic review by Duivenvoorden, et al.,⁹⁴ sought to evaluate the benefits and harms of braces and ankle-foot-orthoses in patients with knee OA. Specific to this evidence review, the focus of this summary will be on the comparison of a valgus knee brace to no brace on pain, knee function, quality of life, and adverse events after 12-months of brace treatment. There were 13 studies included in this analysis; 4 of the studies evaluated the effects of knee braces compared to no treatment for patients with knee OA,^87,90,95,96 with only 1 of these studies reporting enough data at the 12-month follow-up to include in what was described by the authors as a meta-analysis.⁸⁷ Pain was scored on a VAS scale; there was no statistically significant difference between the brace group and the control group (total n = 115) at the 12-month follow-up in mean difference (0%; 95% CI: -8.4 to 8.4), or in absolute (0%; 95% CI: -8.4 to 8.4) and relative (0%; 95% CI: -1.6 to 1.6) percent change. Similar results were found for knee function via the Hospital for Special Surgery knee score [HSS; n = 110; mean difference: 1.00 (95% CI: -2.98 to 4.98); absolute percent change: 1.0% (95% CI: 3.0 to 5.0); relative percent change: 0.01% (95% CI: 0.05 to 0.07)], quality of life via the EQ-5D [n = 117; mean difference: 0.04 (95% CI: -0.12 to 0.04); absolute percent change: 0.04% (95% CI: -0.12 to 0.04); relative percent change: 0.07% (95% CI: -0.2 to 0.07)], and number of adverse events HSS [n = 117; RR: 1.63 (95% CI: 0.94 to 2.28); absolute percent change: 15% (95% CI: -1% to 32%); relative percent change: 63% (95% CI: -6% to 182%)]. Stiffness, treatment failure, and serious adverse events were not reported in the included studies. This systematic review is limited by its mostly narrative nature, with only one study providing enough data to be included in the meta-analysis for brace treatment compared to no brace.

A systematic review by Gohal, et al.,⁹⁷ sought to clarify the effectiveness of offloader knee braces in patients with medial compartment OA. This SR included studies that compared an offloader brace to no brace, lateral-wedged insoles, neoprene sleeves, and/or a neutral brace; the focus of this summary will be on the comparison between an offloader knee brace to no brace on outcomes of pain, mobility, and quality of life. There were 31 studies included in this analysis [18 non-randomized studies (NRS), 13 RCTS; mean follow-up time: 4.3 ± 4.3 months], with a total of 619 participants who received an offloader brace [average age: 58.1 ± 5.7; 54% male; 549/619 (92.2%) available at follow-up]. The NRSs were determined to be of “fair” quality, while the RCTs were deemed “low” quality. There were five (5) studies that compared a valgus offloader brace to no brace (with or without SOC); all five (5) studies were RCTs. Sattari and Ashraf 2011,⁹⁶ Ostrander 2016,⁵² and Kirkley 1999⁹⁰ reported a statistically significant difference in pain in favor of the valgus brace; however, no statistically significant difference in pain was found by Della Croce 2013.⁹⁸ For function and/or mobility, Sattari and Ashraf 2011, Ostrander 2016, and Kirkley 1999 reported a statistically significant difference in mobility in favor of the valgus brace, while no statistically significant difference in function/mobility was reported by Della Croce 2013 and Moyer 2017.⁹⁹ This systematic review is limited by the small sample sizes of the included studies, and heterogeneity of outcome measures and comparison groups in the included literature, which prevented a meta-analysis from being performed.

Evidence Based Guidelines

Clinical practice guidelines for rest orthosis, knee sleeves, and unloading knee braces in knee osteoarthritis. Joint Bone Spine.¹⁰⁰

Summary of guidelines (in relevant part):

Unloading valgus knee braces can be used for symptomatic medial femoro-tibial OA because of short- and mid-term reduction of pain and disability (grade B evidence). They appear to be more effective than neoprene knee sleeves (grade B evidence) and improve quality of life in the short-term (grade C evidence). They favorably modify compressive loads in the medial femorotibial compartment, joint proprioception, isokinetic strength of quadriceps, gait symmetry and perhaps vertical propulsive force (grade C evidence).

The results of observation and responsiveness to unloading knee braces remain inconsistent (grade C evidence). Side effects are various (grade C evidence). The most serious are venous thromboembolic events (grade C evidence). Safety, observance, and responsiveness are therefore important considerations before proposing unloading knee bracing for knee OA (grade C evidence).

Most studies of unloading orthosis are of low quality, namely level-4 ANAES score. High-quality trials are therefore necessary (grade C evidence).

American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee.¹⁰¹

Summary of guidelines (in relevant part):

Tibiofemoral knee braces are strongly recommended for patients with knee OA in whom disease in 1 or both knees is causing a sufficiently large impact on ambulation, joint stability, or pain to warrant use of an assistive device, and who are able to tolerate the associated inconvenience and burden associated with bracing.

Osteoarthritis in over 16s: diagnosis and management. London: National Institute for Health and Care Excellence (NICE).^29,102

Summary of guidelines (in relevant part):

The committee acknowledged that devices may be useful for people with joint instability (when the joint has greater than normal movement in a direction) or abnormal biomechanical loading (when the joint has abnormal features that affect how forces act upon the joint). Different devices may have different indications based on this. For example:

• A knee brace may provide a feeling of support to an unstable joint or may offload a joint compartment most affected by osteoarthritis,

The type of device to use in people with joint instability or abnormal biomechanical loading will vary on the indication and therefore seeking advice from professionals with an expertise in the area (including for correct fitting of the device to reduce the chance of adverse events) is important. The committee also agreed that some people with joint instability and abnormal biomechanical loading may find it difficult to exercise and providing the device may act as an adjunct to support them to participate in further attempts at exercise. Therefore, the committee recommended insoles, braces, tape, splints or supports should not be offered unless

• there is joint instability or abnormal biomechanical loading, and

• therapeutic exercise is ineffective or unsuitable without the addition of a device, and

• the addition of an aid or device is likely to improve movement and function.

The committee agreed that further research was required in this area. The committee acknowledged that the quality of the evidence for devices was limited, with studies including a small number of participants, having inadequate allocation concealment, and being faced with challenges in achieving blinding and using sham devices that may have active effects and so make the comparison difficult. On considering the relative benefits of the treatments identified in this review, they agreed that further research into foot orthoses, ankle braces and toe braces would be most relevant and so made their research recommendation specific to this. The committee were aware of an ongoing randomized controlled trial on the uses of braces in osteoarthritis and therefore they did not make a research recommendation in this area.

Use of devices for osteoarthritis is varied in current practice. Currently, insoles, braces, tape or supports may be used by some people with osteoarthritis because they were previously recommended by NICE (Statement on this recommendation changing: In this review, there was insufficient evidence of benefit to recommend the use of braces, supports and insoles in the management of osteoarthritis. This was in conjunction to evidence of potential harms with braces and insoles. Given this the committee agreed to change this recommendation and replace it with a new recommendation highlighting the uncertainty in the evidence). The recommendations may change practice with using devices. But the practice of using walking aids is unlikely to change. There is a potential for some cost savings to the NHS.

OARSI guidelines for the non-surgical management of knee, hip, and polyarticular osteoarthritis.²⁶

Summary of guidelines (in relevant part):

Level 4A - ≥ 75% “against” & > 50% “conditional” Recommendation for Varus/Valgus Unloading/Realigning Brace.

Topical capsaicin and bracing of the knee (described as a biomechanical intervention in the previous guidelines) were recommended against in the current guidelines due to inadequate efficacy and safety balance, stemming from very poor quality evidence.

The rationale specific to a Varus/Valgus Unloading/Re-alignment Brace was “Low quality evidence, no evidence of benefit for widespread pain.”

An algorithm recommendation for the management of knee osteoarthritis in Europe and internationally: a report from a task force of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO).¹⁰³

Summary of guidelines (in relevant part):

Despite significant heterogeneity and poor trial quality, there is reasonable evidence to suggest that knee braces actually improve biomechanical imbalance and may improve knee OA symptoms.

There is insufficient evidence to determine whether braces or insoles affect the progression of knee OA.

Ideal patients for bracing are younger individuals, more physically active, not severely obese, with unicompartmental symptomatic tibiofemoral OA and malalignment that is reducible by valgus or varus stress maneuvers on physical examination.

A comprehensive review of bracing, like other non-pharmacological interventions, was beyond the scope of the updated ESCEO report in 2019.¹⁰⁴

American Academy of Orthopaedic Surgeons Management of Osteoarthritis of the Knee (Non-Arthroplasty) Evidence-Based Clinical Practice Guideline.¹⁰⁵

Summary of guidelines (in relevant part):

Moderate Strength of Recommendation for: Brace treatment could be used to improve function, pain and quality of life in patients with knee osteoarthritis.

The Braces recommendation has been downgraded one level because of heterogeneity.

Braces can provide significant pain relief and improved function to patients that have unicompartmental knee osteoarthritis. Braces can provide a subjective feeling of more normal tibiofemoral kinematics, preventing excessive strain on the affected compartment while protecting against preexistent concomitant meniscal and chondral injuries. There is also a theoretical benefit of increased confidence in the knee during the different activities by providing a sense of security to the knee. There are almost no harms in trialing a brace besides some skin irritation, or the brace being uncomfortable.

The Royal Australian College of General Practitioners. Guideline for the management of knee and hip osteoarthritis.¹⁰⁶

Summary of guidelines (in relevant part):

We suggest not offering valgus unloading/realignment braces for people with medial tibiofemoral compartment knee OA (Quality of Evidence: Low; Conditional against recommendation).

We are unable to recommend either for or against the use of varus unloading/realignment braces for people with lateral tibiofemoral compartment knee OA (Quality of Evidence: Very Low; no RCT data; Conditional [neutral] recommendation).

PANLAR Consensus Recommendations for the Management in Osteoarthritis of Hand, Hip, and Knee. ¹⁰⁷

Summary of guidelines (in relevant part):

Support devices may be useful for reducing pain and stiffness and improving the functionality of the knee. Insoles and knee braces have been shown to decrease valgus or varus and knee pain. (Level A: Information from various randomized clinical trials or meta-analyses; Strength of Recommendation IIa: Evidence and/or agreement favor usefulness or efficacy).

Department of Veterans Affairs & Department of Defense CLINICAL PRACTICE GUIDELINE FOR THE NON-SURGICAL MANAGEMENT OF HIP & KNEE OSTEOARTHRITIS.¹⁰⁸

Summary of guidelines (in relevant part):

For initial individualized treatment plans, discuss a self-management program:

• • Regular self-directed exercise

• • Comprehensive lifestyle intervention for weight reduction: refer to the current VA/DoD CPG for the Management of Adult Overweight and Obesity

• • Bracing for OA of the knee (prescription of adaptive equipment such as a cane and knee braces may also be offered in conjunction with the above to help decrease weight burden/provide stability for knee OA)

• • Offer referral for physical therapy

The Work Group also considered patient preferences, availability of the braces, and minor complications from valgus knee braces. Valgus knee braces are offered predominantly for patients with OA of the medial compartment with a varus deformity. Some patients may want to avoid braces in hot weather. Minor complications of valgus knee braces are common and may affect the usability of the brace. Soft braces are widely available (generally off-the-shelf) and inexpensive. Valgus knee braces can be relatively expensive, are not widely available, and need custom sizing. Valgus knee braces may be appropriate for patients who are evaluated in orthopedic, physical medicine and rehabilitation, and physical therapy clinics with custom fitting.

Professional Society Recommendations

There were no relevant professional society recommendations identified.

The aim of this summary was to determine if the use of an unloader (i.e., offloading) knee brace, compared to baseline (no brace), sham, or SOC improved pain, mobility and function, quality of life, pain medication usage, and disease progression in Medicare Beneficiaries with medial or lateral compartment knee OA regardless of the presence of objective knee laxity. Studies that were reviewed were analyzed for risk of bias (ROB). For RCTs, ROB was assessed using the Cochrane Collaboration’s tool for assessing risk of bias.^109,110 To evaluate the ROB in non-randomized studies, the ROB in Non-Randomized Studies of Interventions (ROBINS-I) tool was used.¹¹¹ The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach was used as a method of grading the certainty of evidence, which can range from high to very low, and is defined as follows:¹¹²

Certainty of Evidence

Compared to baseline (no brace), there is evidence, based on RCTs, that the use of unloader knee braces may lead to statistically significant improvements in pain (low certainty) and mobility/function (moderate certainty using objective measures; low certainty using patient-reported measures); however, the effects of unloader knee braces on QoL were inconsistent (both no difference and statistically significant difference were found; very low certainty), and there was no difference in medication usage (moderate certainty). The single RCT that evaluated the effects of an unloader knee brace on disease progression was insufficiently powered. Based on NRSs, compared to baseline (no brace), there is evidence that the use of unloader knee braces may lead to statistically significant improvements in pain, mobility/function using objective or patient-report outcome measures, and QoL, as well as a decrease in medication usage and likelihood of undergoing a TKA the longer the brace is worn (all very low certainty).

Compared to a sham brace, there is evidence, based on a single RCT, that the use of an active unloader knee brace may lead to statistically significant greater improvements in pain, mobility/function using patient-reported measures and QoL (all low certainty). No RCTs evaluating the effects of an active unloader knee brace on mobility/function using objective measures, medication usage, or disease progression compared to sham were identified.

Compared to SOC, there is evidence, based on RCTs, that the use of unloader knee braces may lead to statistically significant greater improvements in pain and mobility/function using patient-reported measures (both very low certainty); however, the differential effects of unloader knee braces compared to SOC on mobility/function using objective measures were inconsistent (both no difference and statistically significant difference were found; very low certainty), and there was no difference in QoL or medication usage between the treatment groups. No RCTs evaluating the effects of an unloader knee brace on disease progression compared to SOC were identified. Based on NRSs, compared to SOC, there were no differential effects of unloader knee braces on pain, mobility/function using objective or patient-report outcome measures, opioid use, or progression to TKA (all very low certainty). No NRSs evaluating the effects of an unloader knee brace on QoL compared to SOC were identified.

Conclusion

Unloader (valgus or varus) knee braces use adjustable straps, condylar pads, or pneumatic bladders to apply either a valgus or varus external force on the knee joint for the management of medial or lateral unicompartmental knee OA. Purported benefits of unloader knee braces include reduction of biomechanical forces on the degenerative compartment, realignment of the knee, and potential relief of pain and improvement in function.

Across study designs and comparators, the use of unloader knee braces leads to a consistent direction of effect on pain reduction (low to very low certainty) and mobility and/or functional improvement (moderate to very low certainty) in individuals diagnosed with medial or lateral unicompartmental tibiofemoral knee OA. Importantly, no evidence was identified to support limiting unloader knee braces for individuals with a diagnosis of medial or lateral unicompartmental knee OA only if objective knee laxity is found on physical examination. The heterogeneity in the certainty of the evidence is dependent upon the study design (RCT vs. NRS), comparator [baseline (no brace) vs. SOC vs. sham], type of outcome measure used (objective vs. patient-reported), and duration of follow-up. Generally, the study limitations were similar across most of the analyzed publications and included small sample sizes, short durations of follow-up, missing data, lower compliance rates, and lack of blinding (participants and/or assessors).

Available secondary sources (i.e., systematic reviews, meta-analyses, clinical practice guidelines) evaluating the effects of unloader knee braces in individuals with a diagnosis of medial or lateral unicompartmental knee OA echoed the heterogeneity noted in this analysis and cited similar concerns related to the certainty of the available literature. Despite these issues, the authors of the identified meta-analysis (including more than 1 study) concluded that unloader knee braces improve pain and function, the authors of the identified systematic review concluded the majority of the reviewed literature supported the use of unloader knee braces for the treatment of pain, and finally, most of the evidence-based clinical practice guidelines identified (6 of 9) recommended ‘for’ the use of unloader knee braces in the treatment/management of pain or mobility/functional limitations related to knee OA.

Based on a review of the currently available literature, there is sufficient evidence to support that the use of unloader knee braces may be a potential non-surgical therapeutic option for the reduction of pain or improvement in mobility and/or function in some Medicare beneficiaries with a diagnosis of medial or lateral unicompartmental knee OA, regardless of the presence of objective joint laxity. Therefore, the criteria in the Knee Orthoses Local Coverage Determination will be expanded to allow knee orthoses with single or double upright, adjustable flexion and extension joint, medial-lateral and rotation control with valgus or varus adjustment when an ambulatory beneficiary’s medical record includes a physical examination and imaging report that support the diagnosis of medial or lateral unicompartmental tibiofemoral OA, documentation of pain or mobility and/or functional impairment secondary to medial or lateral unicompartmental knee OA, and documentation of the beneficiary’s willingness to use the knee orthosis.

DOCUMENTATION REQUIREMENTS

Section 1833(e) of the Social Security Act precludes payment to any provider of services unless "there has been furnished such information as may be necessary in order to determine the amounts due such provider." It is expected that the beneficiary's medical records will reflect the need for the care provided. The beneficiary's medical records include the treating practitioner's office records, hospital records, nursing home records, home health agency records, records from other healthcare professionals and test reports. This documentation must be available upon request.

GENERAL DOCUMENTATION REQUIREMENTS

In order to justify payment for DMEPOS items, suppliers must meet the following requirements:

• SWO

• Medical Record Information (including continued need/use if applicable)

• Correct Coding

• Proof of Delivery

Refer to the LCD-related Standard Documentation Requirements article, located at the bottom of this policy under the Related Local Coverage Documents section for additional information regarding these requirements.

Refer to the Supplier Manual for additional information on documentation requirements.

Refer to the DME MAC web sites for additional bulletin articles and other publications related to this LCD.

POLICY SPECIFIC DOCUMENTATION REQUIREMENTS

Items covered in this LCD have additional policy-specific requirements that must be met to justify Medicare reimbursement.

Refer to the LCD-related Policy article, located at the bottom of this policy under the Related Local Coverage Documents section for additional information.

Miscellaneous

Appendices

Utilization Guidelines

Refer to Coverage Indications, Limitations and/or Medical Necessity

N/A

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