Abstract
Aims: Peroneal tendons possess a vascular supply through a mesotendineal structure named vinculum; vincula are identifiable with tendoscopy and are supposed to play a role in tendon healing response, due to prominent vascularity; aim of the study is to verify the feasibility of tendoscopy in evaluating peroneal tendons, to clarify the histological structure of peroneal vincula and to investigate the presence of nervous tissue, so formulating a hypothesis regarding the functional role of vincula.
Methods: cadaver study was performed on 8 fresh-frozen ankles; dissection were conducted to verify accessibility of endoscope, proximity with superficial peroneal nerve and presence of vincula; samples of vincula were obtained; light microscopy and immunohisto-chemistry (anti-human S100 antibody) were performed, describing structure of vincula and identifying peripheral nerve fibers.
5 peroneal vincula biopsies were analyzed from patients affected by ankle instability and undergoing tendoscopy for peroneal tenosynovitis.
Results: peroneal tendons are accessible along the whole common tendon sheath and a discrete distance between the endoscope and the superficial peroneal nerve is present in all specimens; a membranous mesotendineal structure was found in all specimens between both tendons and tendon sheath; macroscopic inspection revealed the presence of a vessel network, arising from the sheath toward the tendon; light microscopy of cadaver samples confirmed the presence of multiple vessel branches crossing the entire structure of the vinculum and identified nervous structures close to the vessels, resembling a neurovascular bundle; immunohistochemical analysis revealed nerve fibers in each specimen;tendoscopy in patients affected by ankle instability showed lesions of the vincula and histology from intraoperative biopsies showed presence of nerve fibers.
Conclusions: tendoscopy is a useful tool to visualize peroneal tendons and to diagnose and treat different disorders; although literature provides no data about innervations of peroneal vincula, the study shows nervous fibers consistently present inside the intimate structure of vinculum; besides its function in repair and healing processes, this suggests a proprioceptive role of the vinculum in peroneal tendon physiology and lesion of vinculum could be an important element acting synergistically with joint capsule and surrounding tissues lesions and ultimately leading to clinical pictures of ankle instability.
The abstracts were prepared by incoming Professor Elena Brach del Prever. Correspondence should be addressed to IORS – President office, Dipartimento di Traumatologia, Ortopedia e Mediciana del Lavoro, Centro Traumatologico Ortopedico - Via Zuretti, 29 I-10135 Torino, Italy.
