Influence of contralateral lower limb stabilization on hip abductor muscle strength measured by Hand-Held Dynamometer

Abstract

Objective: To investigate the influence of contralateral lower limb function on hip abductor muscle strength using a hand-held dynamometer. Method: Thirty healthy subjects and fifty-nine hemiplegic patients participated in this study. Hip abductor muscle strength was measured in the supine position with or without stabilization of the contralateral lower limb (stabilizing vs. nonstabilizing method, respectively). Strength as measured using both methods was compared on each side for the lower limb and correlation coefficients for the two methods were calculated. In addition, correlation coefficients between measurements of strength using the two methods on both sides were calculated. In the hemiplegic patients, multiple regression analysis was performed using the strength on the affected side as the dependent variable, and the strength on the unaffected side and the degree of paralysis as independent variables. Results: Strength measured using the stabilizing method was significantly lower than when using the nonstabilizing method. The correlation between the strength on both sides was high in the healthy subjects despite contralateral lower limb stabilization, but low in the hemiplegic patients when using the nonstabilizing method. The strength on the affected side was strongly influenced by the unaffected lower limb function in measurements using the stabilizing method. Discussion: Measurements of hip abduction strength when using the stabilizing method are not an accurate reflection of the strength due to the influence of contralateral lower limb function.