Lateral trunk lean and medializing the knee as gait strategies for knee osteoarthritis

Abstract

Objective To determine (1) if Medial Thrust or Trunk Lean reduces the knee adduction moment (EKAM) the most during gait in patients with medial knee osteoarthritis, (2) if the best overall strategy is the most effective for each patient and (3) if these strategies affect ankle and hip kinetics. Design Thirty patients with symptomatic medial knee osteoarthritis underwent 3-dimensional gait analysis. Participants received verbal instructions on two gait strategies (Trunk Lean and Medial Thrust) in randomized order after comfortable walking was recorded. The peaks and impulse of the EKAM and strategy-specific kinematic and kinetic variables were calculated for all conditions. Results Early stance EKAM peak was significantly reduced during Medial Thrust (−29%). During Trunk Lean, early and late stance EKAM peak and EKAM impulse reduced significantly (38%, 21% and −25%, respectively). In 79% of the subjects, the Trunk Lean condition was significantly more effective in reducing EKAM peak than Medial Thrust. Peak ankle dorsi and plantar flexion, knee flexion and hip extension and adduction moments were not significantly increased. Conclusions Medial Thrust and Trunk Lean reduced the EKAM during gait in patients with knee osteoarthritis. Individual selection of the most effective gait modification strategy seems vital to optimally reduce dynamic knee loading during gait. No detrimental effects on external ankle and hip moments or knee flexion moments were found for these conditions.