The Effect of Vascular Pedicle Preservation on Blood Flow and Clinical Outcome Following Ulnar Nerve Transposition

Purpose To evaluate the efficacy of a technique to preserve the extrinsic vascular supply to the ulnar nerve after transposition and its effect on blood flow and clinical outcome. Methods We included 36 patients with cubital tunnel syndrome. The patients were randomly selected to undergo vascular pedicles–sparing surgery for anterior ulnar nerve transposition (VP group) or nerve transposition and artery ligation (non-VP group). Blood flow to the ulnar nerve was estimated intraoperatively at 3 locations in the cubital tunnel before and after transposition using a laser Doppler flowmeter. Clinical results at 3, 6, and 12 months after surgery were also compared between the 2 groups. Results The blood flow before ulnar nerve transposition was not significantly different between the groups. Blood flow at all 3 locations after the ulnar nerve transposition was significantly higher in the VP group than in the non-VP group. Blood flow in the non-VP group reduced to values between 28% and 52% from the pre-transposition baseline values. After surgery, no significant differences were observed in the clinical results between the groups, except for the Disabilities of the Arm, Shoulder and Hand scores at 12 months after surgery, which was greater in the non-VP group. Conclusions The procedure of preserving the extrinsic vascular pedicles can prevent compromise of blood flow to the ulnar nerve immediately after nerve transposition. However, this procedure had no correlation to improved recovery of ulnar nerve function after surgery. Type of study/level of evidence Therapeutic II.