Mechanical factors influencing response of joint afferent neurons from cat knee.

The responses of 67 slowly adapting joint afferent neurons in cat posterior articular nerve (PAN) were studied in relation to mechanical stimulation of the knee. The response of most neurons could be interpreted in terms of the stretching of joint tissues resulting from angular displacement of the knee. No neurons discharged at angles intermediate between the limits of movement of the joint. The limits of movement of the joint were operationally defined in terms of displacements resulting from applied torques.