Intrinsic Properties of the Knee Extensor Muscles After Subacute Stroke

Abstract Horstman AM, Gerrits KH, Beltman MJ, Koppe PA, Janssen, TW, de Haan A. Intrinsic properties of the knee extensor muscles after subacute stroke. Objective To characterize muscle properties of paretic lower-limb (PL) and nonparetic lower-limb (NL) knee extensors in patients with subacute stroke. Design Case-control study. Setting Rehabilitation center research laboratory. Participants Patients with subacute stroke (n=14) and able-bodied age-matched control subjects (n=12). Interventions Not applicable. Main Outcome Measures Half relaxation times (HRTs) and maximal rates of torque development (MRTDs) were assessed as indicators of contractile speed using both voluntary and electrically evoked contractions. Moreover, changes in torque were measured during a fatigue protocol (35 electrically evoked intermittent contractions; 1.5s on, 2s off) and recovery. Results No differences among groups were found for normalized MRTDs during electrically evoked contractions ( P =.117). However, during voluntary contractions both PLs (53% of control, P =.022) and NL (71% of control, P