Tibial mononeuropathy from a lower limb synovial cyst.

BACKGROUND

Tibial mononeuropathy due to compression by a synovial cyst is uncommon with fewer than 10 cases reported in the literature.

METHOD: Case Study.

RESULTS

Tibial motor mononeuropathy with focal conduction block between the popliteal fossa and ankle was identified by electrophysiological testing. Magnetic resonance imaging and surgical exploration identified a synovial cyst compressing the nerve just distal to the popliteal fossa.

CONCLUSIONS

The combination of electrophysiological localization and imaging in cases of unexplained tibial mononeuropathy may identify an unexpected structural cause.