An intact nerve preparation for monitoring inputs from single joint afferent fibres

A preparation is described that permits the monitoring of activity from individual joint afferent nerve fibres in an intact peripheral nerve of the cat. The joint nerve used was the medial articular nerve (MAN) that supplies the medial and anteromedial aspects of the knee joint. This nerve is sufficiently fine that if freed from nearby tissue over a length of 2-5 cm and placed over a platinum hook electrode it is possible to identify and monitor, from the intact nerve, the impulse activity from each group II joint afferent fibre activated by mechanical stimulation of the joint capsule. The signal-to-noise ratio exceeds 5:1 and in most cases was approximately 10:1. With this preparation it is now possible to examine the central actions and security of transmission at central synaptic targets for single, identified group II joint afferent fibres.