By Jordana Bieze Foster
Studies presented at the 2013 World Congress on Osteoarthritis, held in April in Philadelphia, provide more evidence that knee bracing can improve pain and gait mechanics in patients with knee osteoarthritis (OA)—improvements that are magnified with increased wear time.
Research from the congress also suggests, however, that those improvements do not appear to be associated with structural changes that would indicate slowed disease progression.
Most of the published research on knee OA bracing has focused on medial tibiofemoral compartment OA, but a randomized trial from the UK presented in Philadelphia suggests bracing can also effectively improve pain and function in patients with primary patellofemoral OA.
Researchers from the University of Manchester randomized 126 patients with symptomatic and radiographic patellofemoral OA to 12 weeks of wearing a patellar tracking brace or six weeks of no brace treatment followed by 12 weeks of brace wear. All patients had a Kellgren-Lawrence score of 2 or 3 in the patellofemoral joint, which was greater than the K-L score in either tibiofemoral compartment, and at least three months of pain, with the worst pain rating at least 40 on a 100-point visual analog scale.
After the first six weeks, in which only one group was braced, the bracing group had significantly better scores than the unbraced group on most measures of pain and function. After both groups had worn the brace for 12 weeks, the pooled results showed significant improvements from baseline on all pain and function measures.
“Patellofemoral bracing significantly improves pain and symptoms in painful patellofemoral joint OA,” said Michael Callaghan, PhD, a research associate in the Arthritis Research Epidemiology unit at the university, who presented his group’s findings in Philadelphia.
Back in the realm of medial tibiofemoral OA, Baltimore researchers found significant improvements in pain and gait mechanics associated with a new brace with pneumatic joint unloading and active swing-assist technology.
In 10 knee OA patients who were instructed to wear the brace for 30 minutes three times a day for three months, researchers from Sinai Hospital in Baltimore found that compliance was associated with significant improvements in pain, thigh girth, and knee adduction moment. Compared to 15 previous patients who were not braced, the braced patients were less likely to undergo viscosupplementation or total knee arthroplasty. The findings were also e-published in November by the Journal of Knee Surgery.
“It’s hard to get people to wear a brace, but if they feel that it’s having an effect, they’re more likely to wear it,” said Anil Bhave, PT, director of the gait laboratory at Sinai Hospital, who presented the findings in Philadelphia.
Similarly, the more patients wear a brace, the more likely they will benefit, according to research from Dalhousie University in Halifax, Nova Scotia, that found a dose response to brace wear in patients with medial tibiofemoral OA. Of 29 patients who wore a custom-fit valgus offloading brace for six months, frontal and sagittal plane kinematics differed significantly between those who wore the brace for more than four hours per day (average nine hours/ day) and those who did not
(average two hours/day). The high-dose group also reported significantly greater symptom improvement from baseline than the low-dose group.
A study from the University of Iowa in Iowa City, however, found that valgus offloading braces did not significantly affect tibiofemoral contact stress in 15 patients with medial or lateral tibiofemoral OA. All patients were regular brace users who had experienced significant symptom relief with brace wear.
Researchers obtained weight-bearing 3D magnetic resonance images and weight-bearing radiographic images of patients’ knees with and without the brace. Computer analysis of the combined imaging data revealed no significant changes in mean or maximum contact stress in the compartment of interest.
Callaghan M, Parkes MJ, Forsythe LM, et al. Beneficial effects of a brace for patellofemoral OA: Results of a randomised trial. Presented at the 2013 World Congress on Osteoarthritis, Philadelphia, April 2013.
Bhave A. Gait and clinical improvement with a novel knee brace for knee OA. Presented at the 2013 World Congress on Osteoarthritis, Philadelphia, April 2013.
Johnson AJ, Starr R, Kapadia BH, et al. Gait and clinical improvements with a novel knee brace for knee OA. J Knee Surg 2012 Nov 6. [Epub ahead of print]
Robbins S, Rutherford D, Hubley-Kozey C, Stanish W. Dosage of valgus unloader braces influence knee mechanics in patients with knee osteoarthritis. Presented at the 2013 World Congress on Osteoarthritis, Philadelphia, April 2013.
Segal NA, Stockman TJ, Kern A, et al. Assessment of the effect of an off-the-shelf realigning brace on tibiofemoral contact stress. Presented at the 2013 World Congress on Osteoarthritis, Philadelphia, April 2013.