Neuromuscular versus quadriceps strengthening exercise in people with medial knee osteoarthritis and varus malalignment

This study aimed to compare the effects of neuromuscular exercise (NEXA) and quadriceps strengthening (QS) on the knee adduction moment (an indicator of medio-lateral distribution of knee load), pain and physical function in persons with medial knee joint osteoarthritis (OA) and varus malalignment. Methods: 100 people with medial knee pain, mostly moderate to severe radiographic medial knee OA, and varus malalignment were assigned at random to one of two 12-week exercise programs. Each program consisted of 14 individually supervised exercise sessions with a physiotherapist plus a home exercise component. Primary outcomes were peak external knee adduction moment (3D gait analysis), pain (visual analogue scale), and self-reported physical function (Western Ontario and McMaster Universities Osteoarthritis Index). 82 participants (38/50 (76%) NEXA, 44/50 (88%) QS) completed the trial. There was no significant between-group difference in the change in the peak knee adduction moment (mean difference (95% CI) 0.134 (-0.069 to 0.337) Nm/(BW.HT)%), pain (2.4 (-6.0 to 10.8) mm) or physical function (-0.8 (-4.0 to 2.4) units). Neither group displayed a change in knee moments following exercise, whereas both groups showed similar significant reductions in pain and physical dysfunction.

Although the study produced comparable improvements in clinical outcomes for both neuromuscular and quadriceps strengthening exercise in individuals with moderate varus malalignment and mostly moderate to severe medial knee OA, these forms of exercise did not affect the knee adduction moment, a key predictor of structural disease progression.