An investigation of neural tissue involvement in ankle inversion sprains

The slump test was used to investigate the effect of ankle inversion sprain on neurodynamic function in 18 subjects. The sensory response and restriction in range of knee extension in the slump test were assessed. Three different foot and ankle positions were used - neutral, dorsiflexion (DF) and plantarflexion with inversion (PFI). Results indicated that although there was a significantly greater lack of knee extension on the injured side compared to the non-injured side in all three foot and ankle positions, knee extension was most restricted in the PFI position, which is considered to bias the common peroneal tract. The slump test in PFI produced symptoms in the lateral aspect of the lower leg and ankle extending slightly anteriorly and posteriorly and into the dorsum of the foot. This distribution corresponds to that of the superficial peroneal nerve. The slump test in neutral and DF produced areas of response similar to each other, which included the posterior aspect of the knee, thigh and calf. The release of cervical flexion resulted in a significant reduction in symptoms in each test. These results may indicate altered neurodynamic function following ankle inversion sprain, and have implications for assessment and treatment of subjects with ankle sprain