[A needle electrode isolation amplifier for biomechanical studies]

In our laboratory for biomechanics, a new isolation amplifier was developed with which to record the electromyographic activity of muscles inaccessible to surface electrodes, in particular that of the rotator cuff. Our basic premisses were maximum safety for the patient or subject investigated, and optimal signal processing. These were achieved by a triple galvanic separation of the patient/subject from the battery power supply and the signal cables and by careful selection of the electronic components.