403 - A Case Report: Femoral Nerve Palsy Following Retroperitoneal Mass Excision – Management and Early Outcomes

A middle-aged person underwent an elective excision of a left retroperitoneal mass extending from the spanning from the level of the aortic bifurcation to the level of the lesser trochanter traversing anterior to the course of the left iliopsoas muscle. The patient then developed left-sided weakness with hip flexion and absent knee extension and anteromedial thigh and leg numbness below the femoral canal, consistent with femoral nerve palsy (FNP). Symptoms continued to persist despite physical therapy. Subsequent and repeat electromyography and nerve conduction studies confirmed severe left sensory and motor FNP. The patient was then referred to orthopedic surgery and underwent obturator to femoral nerve transfer approximately 1-year post-injury. Following the procedure, the patient exhibited sensation recovery along the femoral nerve distribution and is scheduled for physical therapy for quadriceps strengthening and gait training.


Discussions: FNP without intraoperative injury is a rare complication following retroperitoneal surgery.  Management is often conservative with physical therapy and if inflammatory, treated with steroids.  Reconstruction of the left femoral nerve using obturator nerve transfer has shown to be a viable option for recovering function and sensation for FNP that has not shown improvement despite conservative measures.

Conclusions:

This case report demonstrates FNP, a rare complication following retroperitoneal surgery.  Further research is needed to understand the long-term outcome and potential of femoral nerve reconstruction as a treatment option.