Instrumentation for simultaneous recording of compound muscle action potentials and related force in the dog.

An examination apparatus for the study of both compound muscle action potentials and related isometric force of the target muscle after supramaximum electrical stimulation of the respective nerve is described. Force transducers were used to record forces from the forelimb paws and the jaws of the dog. The unit is suitable for the clinical examination of neuromuscular transmission disturbances and for testing the effect of relaxant agents.

Neuromuscular transmission studies in the healthy dog: EMG and muscle force measurement after repetitive nerve stimulation.

In 10 healthy anaesthetized female dogs the ulnar and the mandibular nerve were stimulated supramaximally by repetitive electric impulses according to a fixed programme. To evaluate the neuromuscular transmission system the course of the evoked compound muscle action potential and the near-isometric force of forelimb and masticatory muscles were studied respectively. The presented results are comparable to values obtained from small hand muscles of conscious, healthy human subjects. The simultaneous measurement of both the electrical and the force response may improve the diagnostic accuracy of the examination in presumed neuromuscular transmission failure in the dog, as it does in humans.