Dynamic Nerve Compression of Guyon Canal Secondary to Variation of the Deep Branch of the Ulnar Artery: Etiology, Diagnosis, Treatment, and Outcome

A patient presented with an ulnar-sided left wrist injury that was sustained while batting. Advanced imaging was obtained to rule out common causes of nerve compression and evaluate the patient’s anatomy. Dynamic nerve conduction studies were necessary to confirm a diagnosis of nerve compression. Failing conservative treatments, the patient underwent exploration of Guyon canal and decompression of the ulnar nerve with complete symptom resolution. The patient presented a unique diagnostic challenge because he did not display the typical findings of chronic nerve entrapment syndromes. To the best of our knowledge, dynamic nerve compression at Guyon's canal has not previously been described. It is important to use a systematic approach to diagnosis, eliminating all other sources of compression. With appropriate diagnostic tools, nerve decompression can result in symptom relief.