Effects of knee orthoses on walking capacity and biomechanics in patients with knee osteoarthritis: A critical review.

INTRODUCTION: Gait modification is frequently used as conservative management in knee osteoarthritis (OA). Knee orthoses, such as knee sleeves and unloader knee braces, are nonpharmacological treatment for gait modification in symptomatic knee OA. Previous studies lack systematic investigation of biomechanical effect and functional capacity, particularly walking capacity. This study investigated effects of knee orthoses on biomechanics and walking capacity in patients with knee OA. MATERIALS AND METHODS: A literature search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Physiotherapy Evidence Database (PEDro), and Cochrane Central Register of Controlled Trials (CENTRAL) according to inclusion criteria from 1966 to May 2013. Trials investigating the effects of knee orthoses on biomechanics or walking capacity were collected. Effect size was calculated exclusively according to biomechanical and walking capacity variables reported over 5 publications. Narrative analysis of the studies was performed. RESULTS: The database search provided a total of 1681 citations with 19 studies that investigated effect of neoprene sleeves and unloader knee braces, and satisfied the inclusion criteria. Of these, one was a randomized controlled trial; the other 18 studies were within-subjects, repeated measures designs. Study results indicated unloader knee braces could decrease knee adduction moment, particularly the 2[nd] peak during walking, compared to controls. However, unloader knee braces did not improve walking endurance, and effects on walking speed differed between studies. DISCUSSION: Load-reduction effects of unloader braces used while walking coincide with clinical observations of pain reduction. Our results suggest the mechanism of immediate decrease in knee pain may be due to decreased adduction moment especially at the 2[nd] peak, though this may not affect walking capacity. The conclusions of this review are limited by methodological considerations; therefore, high-quality randomized controlled trials concerning bracing biomechanical changes and functional capacity for knee OA are still necessary.