2023 Volume 40 Issue 4 Pages 666-669
The patient was a 45–year–old man who presented with severe right forearm pain after posterior lumbar interbody fusion surgery for lumbar spinal canal stenosis. Two weeks later, along with the improvement of pain, he suffered from multifocal muscle weakness and atrophy in the right upper extremity. MRI showed swelling of the right brachial plexus. A diagnosis of neuralgic amyotrophy (NA) was made. Treatment with intravenous methylprednisolone and intravenous immunoglobulin partially improved his muscle weakness of the upper extremity. However, muscle weakness persisted in the right ulnar nerve area. MRI revealed right cubital tunnel syndrome, and anterior subcutaneous ulnar nerve transposition was performed. Postoperatively, the weakness of the muscles innervated by the ulnar nerve also improved.
In the present case, in addition to mechanical compression of the ulnar nerve due to cubital tunnel syndrome, an immune reaction induced by lumbar surgery may be involved in the mechanism underlying the onset of NA.
