B. Lindström, B. Gerdle and L. Forsgren
DOI: 10.1080/16501977304754

The ability to perform reciprocal knee flexions and knee extensions was investigated in patients with minimal or no overt motor symptoms after stroke. Ten patients and 22 controls performed 10 maximal reciprocal knee extensions and knee flexions without intervening rest period using an isokinetic dynam- ometer (Cybex II). P eak tor que (P T ; Nm), signal amplitude (RMS) and mean frequency (fmean) of the electromyography were registered for each extension and flexion separately and as the ratio extension/flexion. The patients exhibited pronounced motor deficit despite no or minimal overt clinical symptoms. The reduced motor capacity in the knee muscles was shown as a decrease in the PT and in a different electromyographic pattern compared with the controls. A bilateral affec- tion was found with the formerly hemiparetic side mostly affected. Repeated reciprocal contractions influ- enced the motor performance, shown as an increase of the PT ratio in the patients, which was especially pronounced with an increasing number of contractions