Clinical effect observation of vascularized anterior transposition of ulnar nerve for treatment of severe cubital tunnel syndrome

Objective To evaluate the clinical outcomes of a modified procedure of ulnar nerve anterior transposition in the treatment of severe cubital tunnel syndrome. Methods From September 2015 to May 2016, 25 patients with cubital tunnel syndrome underwent vascularized ulnar nerve anterior transposition were followed up after operation. All the patients had severe muscular atrophy and deformity of elbow joint before operation. According to Gu Yudong's classification of cubital tunnel syndrome, they were graded as severe. In this modified procedure, the sufficient neurolysis of ulnar nerve as well as the anterior transposition of ulnar nerve accompanied with superior ulnar collateral artery were conducted. Results All the 25 patients were follow-up from 12 to 21 months with an average of 15.3 months. All the patients achieved sensory recovery in different degrees without temporary worsening of clinical symptoms. Completely sensory recovery was observed in 20 patients (80%). 4 patients (16%) remained occasional sensory symptoms while only 1 patient (4%) remained persistently moderate sensory symptoms. The mean two-point discrimination of little finger pulp was improved from preoperative 6.08 mm to postoperative 2.93 mm. Obvious improvement of intrinsic muscular atrophy was observed in 17 patients (68%). According to the Gu Yudong's function evaluation standard of cubital tunnel syndrome, the results were excellent in 16 patients, good in 6 patients and fair in 3 patients with the excellent and good rate being 88%. Conclusion The modified technique of vascularized anterior transposition of unlar nerve appears to be an effective and safe procedure for the treatment of severe cubital tunnel syndrome. It might reduce the incidence of postoperative nerve symptoms caused by devascularization of ulnar nerve. Key words: Cubital tunnel syndrome; Ulnar nerve; Vascularized; Anterior transposition