Measurement of patellar and ankle tendon reflexes in normal subjects

In order to acquire normal values, patellar and ankle tendon reflexes were measured bilateral in 51 healthy subjects. The reflexes were mechanically evoked with a hand-held hammer which was connected to the trigger input of a two-channel EMG system. For each reflex simultaneous registration took place from surface electrodes on two different locations. The dependence of the latency on body length and age is described as well as the left-right difference and the intra-individual variability. Using similar measurement conditions significantly longer latencies were found than those published earlier. The importance of well defined placement of the electrodes when comparing acquired latencies with normal values is shown.