Hardware-Associated Superficial Peroneal Nerve Entrapment Following Syndesmotic Stabilization: A Case Report

Persistent neuropathic pain following syndesmotic stabilization should prompt consideration of superficial peroneal nerve (SPN) entrapment. The authors report a rare case of hardware-associated SPN entrapment after syndesmotic stabilization for chronic ankle instability following a triplane ankle fracture and highlight the diagnostic value of ultrasound-guided injection when metallic hardware limits direct nerve visualization.

A 13-year-old female underwent arthroscopic debridement, syndesmotic stabilization, and lateral ligament reconstruction for persistent pain and instability following a triplane ankle fracture. Her pre-operative mechanical symptoms resolved; however, she subsequently developed dorsal foot paresthesias and electric shock-like pain in the distribution of the SPN. Ultrasound evaluation was limited by acoustic shadowing from syndesmotic hardware, but ultrasound-guided diagnostic injection and hydrodissection resulted in complete but transient symptom relief, supporting the diagnosis of hardware-associated SPN entrapment. Surgical exploration demonstrated the SPN immediately adjacent to the syndesmotic fixation construct. SPN decompression and hardware removal resulted in complete resolution of neuropathic symptoms.

Patients who develop new dorsal foot paresthesias, allodynia, or electric shock-like pain following syndesmotic fixation should be evaluated for SPN entrapment. When metallic hardware limits direct nerve visualization, ultrasound-guided diagnostic injection can provide valuable functional information to establish the diagnosis and guide definitive surgical management.