RESUMO
BACKGROUND: Ganglion cysts affecting nerve are rare causes of neuropathy. The formation of intraneural ganglion cysts, once controversial, has recently been clarified. We describe the first modern description of a femoral intraneural ganglion cyst at the hip region. METHODS: A patient presented with a 1 year history of radiating pain, quadriceps weakness and anteromedial leg numbness was found to have a femoral intraneural cyst with a hip joint connection on MRI. RESULTS: Surgical disconnection of the articular branch led to improvement of the neuropathy and resolution of the cyst on postoperative MRI. CONCLUSIONS: The unifying articular (synovial) theory describes the joint origin of intraneural cysts, even when they occur in unusual locations, and their propagation into the parent nerve. Knowledge of this theory can improve outcomes; surgery needs to address the joint origin or capsulolabral defect lest recurrence ensue.