Longitudinal sliding of the median nerve during movements of the upper limb.

An incidental finding during recordings from the median nerve was that the nerve trunk slides longitudinally in its bed when the limb is moved. The amount of movement has been measured in 19 subjects. The observations are discussed with reference to the pathology of entrapment neuropathies and it is suggested that, where longitudinal movement of a peripheral nerve is restricted, continual trauma results from normal movements of the limb.