Original Research

Efficacy of Unloader Bracing in Reducing Symptoms of Knee Osteoarthritis

Am J Orthop. 2016 July;45(5):306-311

References

1. Michaud C, McKenna M, Begg S, et al. The burden of disease and injury in the United States 1996. Popul Health Metr. 2006;4:11.

2. Lawrence RC, Felson DT, Helmick CG, et al; National Arthritis Data Workgroup. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II. Arthritis Rheum. 2008;58(1):26-35.

3. Woolf AD, Pfleger B. Burden of major musculoskeletal conditions. Bull World Health Organ. 2003;81(9):646-656.

4. London NJ, Miller LE, Block JE. Clinical and economic consequences of the treatment gap in knee osteoarthritis management. Med Hypotheses. 2011;76(6):887-892.

5. Hochberg MC, Altman RD, April KT, et al; American College of Rheumatology. American College of Rheumatology 2012 recommendations for the use of nonpharmacologic and pharmacologic therapies in osteoarthritis of the hand, hip, and knee. Arthritis Care Res. 2012;64(4):465-474.

6. McAlindon TE, Bannuru RR, Sullivan MC, et al. OARSI guidelines for the non-surgical management of knee osteoarthritis. Osteoarthritis Cartilage. 2014;22(3):363-388.

7. Gallelli L, Galasso O, Falcone D, et al. The effects of nonsteroidal anti-inflammatory drugs on clinical outcomes, synovial fluid cytokine concentration and signal transduction pathways in knee osteoarthritis. A randomized open label trial. Osteoarthritis Cartilage. 2013;21(9):1400-1408.

8. Pollo FE, Jackson RW. Knee bracing for unicompartmental osteoarthritis. J Am Acad Orthop Surg. 2006;14(1):5-11.

9. Ramsey DK, Russell ME. Unloader braces for medial compartment knee osteoarthritis: implications on mediating progression. Sports Health. 2009;1(5):416-426.

10. Zhang W, Moskowitz RW, Nuki G, et al. OARSI recommendations for the management of hip and knee osteoarthritis, part II: OARSI evidence-based, expert consensus guidelines. Osteoarthritis Cartilage. 2008;16(2):137-162.

11. Richmond J, Hunter D, Irrgang J, et al; American Academy of Orthopaedic Surgeons. American Academy of Orthopaedic Surgeons clinical practice guideline on the treatment of osteoarthritis (OA) of the knee. J Bone Joint Surg Am. 2010;92(4):990-993.

12. Kellgren JH, Lawrence JS. Radiological assessment of osteo-arthrosis. Ann Rheum Dis. 1957;16(4):494-502.

13. Dugdale TW, Noyes FR, Styer D. Preoperative planning for high tibial osteotomy. The effect of lateral tibiofemoral separation and tibiofemoral length. Clin Orthop Relat Res. 1992;(274):248-264.

14. Weinstein AM, Rome BN, Reichmann WM, et al. Estimating the burden of total knee replacement in the United States. J Bone Joint Surg Am. 2013;95(5):385-392.

15. Ramsey DK, Briem K, Axe MJ, Snyder-Mackler L. A mechanical theory for the effectiveness of bracing for medial compartment osteoarthritis of the knee. J Bone Joint Surg Am. 2007;89(11):2398-2407.

16. Haim A, Wolf A, Rubin G, Genis Y, Khoury M, Rozen N. Effect of center of pressure modulation on knee adduction moment in medial compartment knee osteoarthritis. J Orthop Res. 2011;29(11):1668-1674.

17. Pollo FE, Otis JC, Backus SI, Warren RF, Wickiewicz TL. Reduction of medial compartment loads with valgus bracing of the osteoarthritic knee. Am J Sports Med. 2002;30(3):414-421.

18. Shelburne KB, Torry MR, Steadman JR, Pandy MG. Effects of foot orthoses and valgus bracing on the knee adduction moment and medial joint load during gait. Clin Biomech. 2008;23(6):814-821.

19. Lewek MD, Ramsey DK, Snyder-Mackler L, Rudolph KS. Knee stabilization in patients with medial compartment knee osteoarthritis. Arthritis Rheum. 2005;52(9):2845-2853.

20. Lewek MD, Rudolph KS, Snyder-Mackler L. Control of frontal plane knee laxity during gait in patients with medial compartment knee osteoarthritis. Osteoarthritis Cartilage. 2004;12(9):745-751.

21. Draganich L, Reider B, Rimington T, Piotrowski G, Mallik K, Nasson S. The effectiveness of self-adjustable custom and off-the-shelf bracing in the treatment of varus gonarthrosis. J Bone Joint Surg Am. 2006;88(12):2645-2652.

22. Barnes CL, Cawley PW, Hederman B. Effect of CounterForce brace on symptomatic relief in a group of patients with symptomatic unicompartmental osteoarthritis: a prospective 2-year investigation. Am J Orthop. 2002;31(7):396-401.

23. Brouwer RW, van Raaij TM, Verhaar JA, Coene LN, Bierma-Zeinstra SM. Brace treatment for osteoarthritis of the knee: a prospective randomized multi-centre trial. Osteoarthritis Cartilage. 2006;14(8):777-783.

24. Larsen BL, Jacofsky MC, Brown JA, Jacofsky DJ. Valgus bracing affords short-term treatment solution across walking and sit-to-stand activities. J Arthroplasty. 2013;28(5):792-797.

25. Hewett TE, Noyes FR, Barber-Westin SD, Heckmann TP. Decrease in knee joint pain and increase in function in patients with medial compartment arthrosis: a prospective analysis of valgus bracing. Orthopedics. 1998;21(2):131-138.

Results

Of the 50 patients randomized, 31 (16 brace, 15 control) completed the study. Of the 19 dropouts, 10 were in the brace group (4 dropped out because of brace discomfort) and 9 in the control group (5 dropped out because of significant pain and the desire for more aggressive treatment with injections). The target patient numbers based on the power analysis were not achieved because of patient enrollment difficulties resulting from the strict criteria established in the study design.

The brace group consisted of 8 men and 8 women. Braces were worn an average of 6.7 hours per day. The control group consisted of 8 men and 7 women. The groups were not significantly different in age, height, weight, body mass index, measured varus knee angle, or arthritis grade (Table 1).

Radiographs were assessed by 2 orthopedic surgeons. Varus angle measurements showed high interobserver reliability (.904, P = .03) and high intraobserver reliability (.969, P = .05); arthritis grades showed low interobserver reliability (.469, P = .59) and high intraobserver reliability (.810, P = .001).

KOOS results showed that, compared with control patients, brace patients had significantly less pain (P < .001), fewer arthritis symptoms (P = .007), better ability to engage in activities of daily living (ADLs) (P = .008), and better total knee function (P = .004) (Figures 1-4). The groups did not differ in ability to engage in sport and recreation (P = .402) or in knee-related quality of life (P = .718), but each parameter showed a trend to be better in the brace group. There was no effect of time in any KOOS subscale. Confidence intervals for these data are listed in Table 2.

VAS results showed that, compared with control patients, brace patients had significantly less pain throughout the day (P = .021) and better activity levels (P = .035) (Figures 5, 6). The groups did not differ in ability to sleep (P = .117) or NSAID use (P = .138), but each parameter showed a trend to be better in the brace group. There was no effect of time in either VAS.