More Resources

Bannuru et al. (2019)

OARSI guidelines for the non-surgical management of knee, hip, and polyarticular osteoarthritis. Osteo. Cartl. 27(11).

Binkley et al. (1999)

The Lower Extremity Functional Scale (LEFS): scale development, measurement properties, and clinical application. Phys. Ther. 79(4).

Duncan et al. (2006)

Prevalence of radiographic osteoarthritis – it all depends on your point of view. Rheum. 45(6)

Hart et al. (2017)

The prevalence of radiographic and MRI-defined patellofemoral osteoarthritis and structural pathology: a systematic review and meta-analysis. B. J. Sports Med. 51(16).

Heekin & Fokin (2014)

Incidence of bicompartmental osteoarthritis in patients undergoing total and unicompartmental knee arthroplasty: is the time ripe for a less radical treatment?. J. Knee Surg. 27(1).

Jevsevar (2013)

Treatment of osteoarthritis of the knee: evidence-based guideline, 2nd edition. J. Am. Acad. Orthop. Surg. 21(9).

McAlindon et al. (2014)

OARSI guidelines for the non-surgical management of knee osteoarthritis. Osteo. Cartl. 22(3).

Messier et al. (2018)

Intentional weight loss in overweight and obese patients with knee osteoarthritis: is more better? Arthritis Care Res. (Hobokin) 70(11).

Military Case Study

Levitation TCO Knee Brace Case Study: 18-year-old male with patellar dislocation, fracture, and osteochondral lesion.

Tubach et al. (2005)

Evaluation of clinically relevant states in patient reported outcomes in knee and hip osteoarthritis: the patient acceptable symptom state. Ann. Rheum. Dis. 64(1).

Zhang et al. (2008)

OARSI recommendations for the management of hip and knee osteoarthritis, part II: OARSI evidence-based, expert consensus guidelines. Osteo. Cartl. 16.

Research Summary

Strength and functional improvement using pneumatic brace with extension assist for end-stage knee osteoarthritis

Cherian, J.J., Bhave, A., Kapadia, B.H., Starr, R., McElroy, M.J., and Mont, M.A. (2015) J. Arthroplasty. 30(5): 747-53. doi: 10.1016/j.arth.2014.11.036.

Key Findings


Increased quadriceps strength

Brace users experienced a 54% gain to their quadriceps muscle strength.


Increased Hamstring strength

Brace users experienced a 24% gain to their hamstring muscle strength.

Functional test improvements

Brace users made significant improvements in three functional tests.

A novel pneumatic offloader brace (OA Rehabilitator) with an active swing-assist and neuromuscular retaining properties was evaluated across multiple patient outcomes in a prospective, randomized trial. After a minimum of 3 months, patients were assessed for changes in muscle strength, objective function, subjective function, pain, quality of life, and conversion to total knee arthroplasty. When compared with a matched cohort, the patients, all of whom had end-stage knee osteoarthritis (OA), showed significant improvements in muscle strength, several functional tests, and patient reported outcomes.

Relevance to Spring Loaded Braces

The novel brace in Cherian et al. (2015), the OA Rehabilitator, has been subsequently evaluated in comparison to a Spring Loaded knee brace. In a recent study, both braces were shown to reduce internal joint contact forces as a result of their offloading capabilities, although they differed to the degree to which they are able to offload the knee 1– Budarick, A.R. et al. (2020). J. Biomech. Eng. 142(1). While the OA Rehabilitator produced joint offloading equivalent to losing 5 lb of bodyweight, the Spring Loaded knee brace resulted in a reduction of joint forces equivalent to losing 45 lb of bodyweight. The subsequent study also compared their assistive moments across a range of brace flexion angles, with the Spring Loaded brace providing larger moments at higher angles than the OA Rehabilitator.

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