Lower extremity peripheral nerve pathology: Utility of preoperative ultrasound-guided needle localization before operative intervention

Historically, the use of ultrasound (US) in the management of peripheral nervous system (PNS) pathology has been limited to diagnostic confirmation or guidance for interventional injections. This technical case series will demonstrate the utility and versatility of preoperative US-guided needle localization for the excision of lower extremity neuromas and other pathology of the PNS. Five patients with symptomatic lower extremity PNS tumors were retrospectively reviewed. This case series corroborates the technical nuances of localizing lower extremity neuromas by US-guided needle and wire placement prior to operative excision. This was achieved by a multidisciplinary team that included plastic surgery, neurosurgery, and radiology. Five patients had US-guided needle localization of a lower extremity PNS target prior to operative intervention. Three patients had lower extremity neuromas of varying origins, including the lateral femoral cutaneous nerve (LFCN), saphenous nerve, and sural nerve. The remaining two patients had a sciatic nerve sheath Schwannoma and a femoral nerve glomus tumor. Under sonographic visualization, a needle was advanced to the target perimeter and withdrawn, leaving behind a percutaneous guidewire. This technique simplified the marking of the nerve course prior to dissection and led to efficient intraoperative identification of all five PNS tumors without any complications. Preoperative US-guided needle localization led to safe, accurate, and efficient perioperative and intraoperative identification of neuromas and other PNS tumors of the lower extremity prior to excision. By reducing the challenges of nerve identification in a scarred tissue bed, this multidisciplinary approach may decrease postoperative patient morbidity.