Isolated musculocutaneous neuropathy after posterior spine surgery for a patient with a subset of Marfan syndrome: A case report

Abstract

The authors reported a 58-year-old male who suffered from severe low back pain due to kyphoscoliosis associated with congenital contractural arachnodactyly (CCA), a subset of Marfan syndrome. Posterior spinal corrective fusion surgery from T8 to the pelvis with pedicle subtraction osteotomy at L4 was conducted. Because of long upper extremities due to CCA, we had no choice but to keep his shoulders abducted 90°, horizontal flexed 30°, and elbow flexed 120° with the conventional arm table during the surgery. Immediately after the surgery, he complained of numbness on the lateral aspect of his right forearm, difficulty of elbow flexion, and supination. Postoperative upper arm magnetic resonance imaging revealed evidence of coracobrachialis, brachialis, and biceps brachii myositis resulted from denervation by musculocutaneous nerve. We diagnosed his symptoms as postoperative isolated musculocutaneous neuropathy (MCNP) based on physical and radiological findings. Weakness and numbness began to be resolved 1.5 months after the surgery. Active motion of the elbow started to recover two months after the surgery and completely recovered six months postoperatively. The potential cause of our patient’s pathology was regarded to be intraoperative malposition of the abnormal long arms. In conclusion, we reported a case of isolated MCNP after thoracolumbar spine surgery under prone position, which is extremely rare and not well known among surgeons. Therefore, spine surgeons should take care of arm position and joint angle even though prone surgery to prevent MCNP, particularly in the patient with long arm span because of Marfanoid.

Keywords

• Musculocutaneous neuropathy (MCNP)
• Peripheral nerve neuropathy
• Complication
• Prone position
• Posterior spine surgery