Ulnar Nerve and Ulnar Artery Injury Caused by Comminuted Distal Radius Fracture

Abstract

Introduction: Distal radius fractures are one of the most frequent traumas encountered in daily orthopedic practice. With this case report, we would like to emphasize the significance of an unexpected associated ulnar nerve and artery injury with distal radius fracture to physicians.

Case report: A 56-year-old male patient was evaluated in the emergency room after a motorcycle accident. The left wrist had a deformity and swelling, and about 3 × 1.5 cm of superficial skin abrasion was found in the volar surface of the wrist. It was noted that distal pulses were palpable, no neurological damage was found except hypoesthesia in the 5th finger. Radiologic examination revealed that the right shoulder was dislocated, and there was a displaced comminuted distal radius fracture in the left wrist with a non-displaced fracture of the ulnar styloid. The fracture was treated with open reduction and internal fixation using volar anatomic plate through the volar approach. After the surgery, pre-operative numbness did not resolve and opposing that expected; it increases with associated pain on the ulnar nerve innervated area within 30 days. The electromyographic analysis revealed severe partial ulnar nerve injury. The surgical exploration of the nerve was decided. The ulnar nerve was found to be trapped in scar tissue, and intimal injury and consequent thrombosis were observed at the ulnar artery.

Conclusion: Distal radius fractures are well-known fractures among the orthopedic surgeons; median nerve compression with a fracture is also within the expectation of the physician. However, the injury of the ulnar nerve and artery is unexpected. With this case report, we would like to emphasize the awareness of the diagnosis and treatment of this kind of associated unexpected ulnar nerve and artery injuries.

Keywords: Distal radius fracture; Guyon’s canal; ulnar artery injury; ulnar nerve injury.

Figure 1

Notice the displacement on lateral radiograph.

Figure 2

Post-operative anterior-posterior and lateral radiograms. Notice the smooth reduction.

Figure 3

(a) The black arrow shows the starting point of compression on the ulnar artery and nerve, the asterix shows stenotic segment of the artery and the red arrow shows the ulnar nerve over the scar tissue. (b) Two black arrows demonstrate the thrombosis and ondulation on the ulnar artery.

Figure 4

Asterix demonstrates the thrombosis and discoloration on the artery and yellow arrow shows the stenotic segment, notice the red coloration on the surface of the artery.

Figure 5

The yellow arrow shows the excised thrombotic segment of the ulnar artery.

Figure 6

(a) Exposure of the basilic vein, the yellow arrow shows the vein. (b) The harvested vein graft reversed and ready for anastomosis.

Figure 7

The yellow arrows show the proximal and the distal side of the anastomosis. The blue arrow shows the body of the vein graft, which filled with blood, the evidence that the anastomosis is actively working.

Figure 8

Notice the appearance of the wrist and hand with full function, 8 months after the second surgery.

Figure 9

Notice the appearance of the wrist and hand with full function, 8 months after the second surgery.

Figure 10

Notice the appearance of the wrist and hand with full function, 8 months after the second surgery.