Effect of double-leg semi-squats with hip adduction on the vastus medialis oblique of patients with patellofemoral pain syndrome / 中华物理医学与康复杂志

ABSTRACT

Objective To investigate the possible effect of performing double-leg semi-squats with hip adduction on the imbalance between vastus lateralis (VL) and vastus medialis oblique (VMO) muscles of patients with patellofemoral pain syndrome (PFPS).Methods Thirty patients with PFPS were selected to be in the study group,matched with 30 healthy subjects who were enrolled as the control group.Electromyography was used to record VL and VMO activities while the subjects performed double-leg semi-squats (DSs) and double-leg semi-squats with hip adduction (DSs-HA).Results In the study group,when performing DSs,the average RMS was (103.31 ± 44.54) μV and the IEMG was (8.02 ±3.45) μVs for VL.For VMO the RMS was (85.02 ±41.19) μV and the IEMG was (6.72 ±3.20) μVs.The differences in the time domain indexes (RMS,IEMG) between VL and VMO were both significant during DSs (P ＜ 0.05).There was no significant differences during DSs-HA (P ＞ 0.05).The time domain indexes (RMS,IEMG) of VMO were significantly different in both the DSs and DSs-HA (P ＜ 0.05).Conclusions Stronger sEMG signals were seen from the VMO in the double-leg semi-squats with hip adduction than without hip adduction,which indicates that more selective VMO activation can be obtained in the exercise with hip adduction to help balance the VL and VMO.