The End-to-Side Neurorrhaphy in Axillary Nerve Reconstruction in Patients with Brachial Plexus Palsy

Abstract

Sir:FigureAlthough a number of theoretical and experimental studies dealing with end-to-side neurorrhaphy have been published to date, there is still a considerable lack of clinical trials. In this communication, we describe our experience with end-to-side neurorrhaphy in axillary nerve reconstruction in patients with upper brachial plexus palsy. Of 791 reconstructed nerves in 441 patients operated on from 1993 to 2011, we performed 21 axillary nerve sutures onto median, ulnar, and radial nerves from 1999 to 2007. This technique was performed only in patients whose “classic donors” such as the thoracodorsal or long thoracic nerve that we generally use for repair of the axillary nerve were not available. The average age of the patients was 32 years. The average time between the trauma and surgery was 4.8 months (Table 1).Table 1: Data for Patients with End-to-Side Neurorrhaphy of the Axillary Nerve onto the DonorIn all patients, a perineurial suture was carried out after the creation of a perineurial window (Fig. 1). It is our standard technique because it has been shown in experimental models that the success rate of such sutures is much higher.1 The precise site on the donor nerve where end-to-side neurorrhaphy was to be performed was chosen by direct bipolar electrical stimulation and registration in the corresponding muscle. There were no signs of denervation of the donor nerve after the perineurial window was created in experimental models.1,2 Similarly, none of our patients had any sensory or motor loss in the innervation zone of the donor nerve, contrary to the Oberlin technique, which carries a risk of sensory loss and, rarely, weakness of hand movements.5Fig. 1: End-to-side neurorrhaphy of the axillary nerve (A) onto the ulnar nerve (UN).The axillary nerve reinnervated successfully in 10 of 21 patients (average follow-up, 30.7 months; Medical Research Council grade 3 to 4 during shoulder abduction over 30 degrees). In four patients, no electrophysiologic signs of reinnervation were observed. In contrast, seven patients whose electromyograms showed reinnervation potentials exhibited insufficient deltoid function (Medical Research Council grade 1, and in one case, grade 2). The success rate was 47.6 percent. The use of different donor nerves (ulnar or median) did not affect the success rate. In the study with the largest series of patients published to date, the author reported good results with reconstructions of various nerves in the upper extremities. These results, however, are not comparable to our study because of a large variety of both donors and recipients.4 We previously reported successful reinnervation using end-to-side neurorrhaphy in 64 percent of patients. These results were based on 14 patients who completed a sufficient follow-up period.3 In the present study, the success rate was 47.6 percent, suggesting that the chance of successful reinnervation using end-to-side neurorrhaphy is lower than we previously thought. The results of end-to-side neurorrhaphy in brachial plexus reconstruction are similar to neurotization using the extraplexus nerves as donors of motor nerve fibers in end-to-end neurotization. Generally, a limited amount of motoneurons have the capacity to send off collateral sprouts from intact axons.2 We conclude that end-to-side neurorrhaphy should be used in adult brachial plexus reconstructive surgery only if “classic donor nerves” are not available. One advantage of end-to-side neurorrhaphy over “classic” neurotization is that there is no need to sacrifice the surrounding nerves or fascicles of the ulnar nerve (Oberlin technique). Pavel Haninec, M.D., Ph.D. Radek Kaiser, M.D. Third Faculty of Medicine, Charles University, Department of Neurosurgery, Faculty Hospital Kralovske Vinohrady, Prague, Czech Republic DISCLOSURE The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this article. ACKNOWLEDGMENT This study was supported by grants IGA NS 10496-3/2009 and MSM 0021620816.