Feasibility of neurovascular antropylorus perineal transposition with pudendal nerve anastomosis following anorectal excision: a cadaveric study for neoanal reconstruction.

PURPOSE: Perineal transposition of the antropyloric valve following an anorectal excision as a substitute for a permanent colostomy has recently been reported in humans. However, the problem of neural control still remains in these patients. Our aim herein was to study the anatomical feasibility of an anastomosis between the pudendal nerve branches (inferior rectal nerve) innervating the external anal sphincter and the anterior vagal branches of the perineally-transposed antropyloric segment in cadavers. METHODS: The antropyloric segment, along with its carefully dissected branch of the anterior vagus, was mobilized based on the left gastroepiploic pedicle in six fresh human cadavers. The antropyloric valve was then transposed in the perineum after the pudendal nerve branches had been dissected out, and an approximation of these two nerves was performed to ascertain the technical feasibility of their neural anastomosis. RESULTS: The anterior vagus innervating the antropylorus could be harvested in all cadavers below the hepatic division of the main vagus trunk. The inferior rectal nerve or its branches were found consistently around the 3 or the 9 o'clock position in the ischioanal fossa. An anatomical tension-free approximation of the anterior vagus branch (of the transposed antropyloric segment) to the inferior rectal nerve in the perineum was feasible in all the cadavers studied. CONCLUSION: An inferior rectal nerve anastomosis with the anterior vagal branch of the perineally-transposed antropyloric segment can be achieved anatomically. This preliminary step can be the basis for future animal studies and subsequent clinical application of the procedure for possible neural control of the transposed antropyloric segment in the perineum.

Study of vascular supply of lunate and consideration applied to Kienböck disease.

The purpose of this study was to assess vascularity of the lunate by number of foramina and radiography of vessels of the wrist. The genesis of lunatomalacia requires some vascular risk and mechanical predisposition. The findings were correlated with the cause of Kienböck's disease. The vascular foramina were more than two in 91.33% of the lunate. The lunate had consistent dorsal and palmar branches from radial artery. The additional branches from anterior interosseous artery in 72.22% and a branch of palmar inter carpal arch in 69.44% cases contributed in arterial anastomosis on palmar aspect of lunate. The dorsal blood supply was found by anterior interosseous artery in 85.71% of specimens and dorsal branch from dorsal intercarpal arch in 50% of specimens. The blood supply of lunate comes along with various ligaments which may be disrupted due to trauma or strain leading to avascular necrosis. The present observations are suggestive of rich blood supply of lunate in comparison of other investigations. Therefore Kienböck's disease is less common in northern India.

Anomalous formation of external jugular vein and its clinical implication.

INTRODUCTION: The superficial veins, especially the external jugular vein (EJV), are increasingly being utilized for cannulation to conduct diagnostic procedures or intravenous therapies. EJV is also used in microsurgical procedures,used as a recipient for the free flaps. MATERIALS AND METHODS: During routine dissection a variation was observed in the formation of EJV unilaterally on the left side. RESULT: In the anterior triangle of the neck submandibular vein joined with the anterior jugular vein to form a large venous trunk (V1). Facial vein joined this venous trunk (V1) to form another common channel (V2). The retromandibular vein divided into unusually long anterior and posterior divisions. Anterior division did not join the facial vein but drained into the common channel V2.The posterior division of retromandibular vein also drained into V2 which further continued as EJV and drained into the subclavian vein. CONCLUSION: The knowledge of variations in the patterns of superficial veins is important for the surgeons to avoid any intraoperative error which might lead to unnecessary bleeding.