Complex Regional Pain Syndrome Type II Associated with Lumbosacral Plexopathy: A Case Report

Abstract

Complex regional pain syndrome (CRPS) is a well-known clinical entity, first described in the 1800s, consisting of pain, hyperalgesia, edema, and sudomotor changes either without (Type I) or with (Type II) a definable nerve injury. CRPS Type II is most commonly caused by high velocity missile injuries, mononeuropathies, and partial nerve transections. In this case, a 25-year-old soldier who sustained a blast injury causing multiple spinal compression fractures, extremity fractures, and pelvic and sacral fractures was transferred to a U.S. Army medical center for surgical management and rehabilitation. He complained of weakness, sensory changes, and pain in his left lower extremity. The patient also demonstrated swelling and hyperesthesia of the left foot and ankle. Undiagnosed soft tissue injury, fracture, and deep venous thrombosis were ruled out by imaging studies. The patient had an electromyogram/nerve conduction study (EMG/NCS) that showed widespread left sided lumbosacral plexopathy as well as possible cauda equina injury. Triple phase bone scan demonstrated findings consistent with CRPS of the left foot and ankle. He was started on a tricyclic antidepressant and an anticonvulsant. Physical and occupational therapy were quickly engaged to incorporate range of motion exercises, mirror therapy, and physical modalities. The patient continued conservative management and rehabilitation and eventually was discharged with significantly improved function and decreased pain. Although many causes of CRPS Type II have been described, this is only the second reported case of CRPS Type II secondary to lumbosacral plexopathy in the literature.