Endoscopic Thoracodorsal Neurectomy for Correction of Animation Deformity following Latissimus Dorsi-Based Breast Reconstruction.

Abstract

Sir: Painful muscular contractions, involuntary twitching, tightness, and/or dynamic displacement of the breast affect a high percentage of patients (41 percent) undergoing innervated latissimus dorsi–based breast reconstruction.1 These sequelae can limit physical activity, jeopardize satisfaction, and diminish quality of life for individuals who have otherwise achieved a favorable aesthetic result. Studies evaluating the impact of surgical denervation of the latissimus dorsi muscle demonstrate significantly reduced pain and animation; comparable preservation of volume, shape, and symmetry; and improved satisfaction following thoracodorsal neurectomy.2,3 It is therefore our preference to perform primary nerve resection during immediate or delayed breast reconstruction, which is readily accomplished through an open axillary or dorsal approach and eliminates the need for a second-stage procedure. Nevertheless, plastic surgeons must also be familiar with treatment strategies for patients who present with secondary contractile deformities. In such cases, chemical denervation with botulinum toxin type A offers a temporary solution; however, results with this approach are unpredictable, and the need for repeated injections over time increases the risk of implant leakage and/or rupture.4 Alternatively, delayed proximal resection of the thoracodorsal nerve may offer the best available option for symptomatic relief. Although high success rates have been reported using an axillary approach (90 percent), sectioning of the latissimus dorsi muscle to access the thoracodorsal nerve is excessively destructive and may alter muscle tropism and contour without guaranteeing successful denervation.1 Furthermore, scarring and/or fibrosis, which are often encountered during secondary revisions, increase the risk and complexity of dissection and the need for more extensive incisions.4 In this communication, we propose a minimally invasive, endoscopic approach to thoracodorsal neurectomy that minimizes incisions, bypasses axillary scarring, and eliminates dynamic abnormalities through selective denervation of the latissimus dorsi muscle. With the patient in lateral decubitus position, endoscopic visualization of the thoracodorsal neurovascular hilus is achieved using carbon dioxide insufflation (10 mmHg) through a 3-mm trocar inserted along the posterior axillary line. Two additional trocars placed distal to the dorsocaudal border of the latissimus dorsi permit unobstructed dissection through the nonirradiated, dorsal submuscular plane. Once identified on the undersurface of the muscle, the thoracodorsal nerve is isolated proximal to the point of divergence from the vascular pedicle and clipped (Fig. 1). Proximal resection of at least 4 cm of extramuscular nerve is then performed under endoscopic guidance, following confirmation of latissimus dorsi contraction on nerve stimulation (Fig. 2).Fig. 1: Endoscopic view of the thoracodorsal neurovascular bundle in situ. The nerve (arrow) is traced proximal to the point of divergence from the vascular pedicle, isolated, and clipped to prevent nerve sprouting and/or aberrant regeneration from adjacent nerve fibers following segmental resection.Fig. 2: A minimum of 4 cm of extramuscular nerve is routinely excised, proximal to the neurovascular hilus, to minimize the risk of latissimus dorsi reinnervation along the vascular pedicle.It is important to note that both muscular reinnervation and incomplete/distal nerve transection may contribute to compromised results and/or persistent animation.4 Technical error can be prevented through segmental resection of the main thoracodorsal nerve trunk—proximal to the neurovascular hilus—using a dorsal approach to avoid injuring the latissimus dorsi muscle and any structures embedded within the scarred axillae. As recommend by Schroegendorfer et al., at least 4 cm of thoracodorsal nerve is resected to achieve permanent sufficient denervation.5 We routinely clip the proximal/distal ends to prevent nerve sprouting and/or aberrant regeneration from adjacent nerve fibers. As with other minimally invasive techniques, improved scarring, reduced pain, and earlier postoperative recovery can be expected following endoscopic thoracodorsal neurectomy for correction of latissimus dorsi–based contractile deformities. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. Michael V. DeFazio, M.D. Troy A. Pittman, M.D. Department of Plastic Surgery Medstar Georgetown University Hospital Washington, D.C.