Endoscopic Techniques In Improving The Effect Of Peripheral Nerves Repair: Application Basis And Clinical Study

ObjectiveTo prove the feasibility and efficacy of endoscopic techniques in peripheral nerves operation, nerve was endoscopically explored to record nerve action potential (NAP), and neurolysis as well as electric stimulation was also delivered via endoscope in animal studies. The experimental results provided laboratory basis for potential clinical application.Materials and methods12 male adult beagle dogs were divided into 3 groups, with 4 each. Sciatic nerves were transected 2cm proximal to the popliteal fossa and sutured immediately. Postoperative management varied according to group assignment. In group A (endoscopic group) the repaired sciatic nerve was endoscopically explored to examine the suture site and record nerve action potential 2 weeks after the operation. Neurolysis and electric stimulation was also delivered via endoscope. The procedure was repeated once every week until nerve regeneration potential was detected distal to the suture site. The same procedures were followed in group B (surgical group) except that all was done in open surgery. In group C (control) there was no postoperative intervention. General condition, functional recovery and electrophysiological changes were followed-up periodically, and the time when neonatal potential of triceps muscle appeared was recorded. 6 months after theoperation, the quality of nerve coaptation was judged by surgical exploration and electrophysiological detection.ResultsRegeneration potential was detected distal to the nerve coaptation site 3 weeks after the operation in groups A and B. Neonatal potential of the triceps muscle was recorded 6 weeks post-op in groups A and B and 7 weeks post-op in group C. Hindlimb function almost recovered in groups A and B 6 months after the operation. There were no significant differences in motor nerve conductive velocity (MNCV) and compound muscle action potential (CMAP) between these two groups. Compared with group C, both of them were statistically better (P<0.05). But in group B, scar hyperplasia was more evident than that in group A.ConclusionEndoscopic techniques were applied in the sciatic nerve exploration and neurolysis in beagle dogs. Combined with NAP, nerve suture quality was judged early and accurately. Electric stimulation via endoscope improved nerve functional recovery. Besides, it was a minimally invasive technique with less scar.Part two: Anatomical studyI .Anatomical study of endoscopic surgical entry path of the ulnar nerveObjectiveTo study the anatomic adjacent structures, branch course and concomitant vessels of the ulnar nerve and design the surgical entry path and the key point of operation for clinical endoscopic harvesting of the ulnar nerve.Materials and methodsThe course, branches, adjacent structures and surface signs of the ulnar nerves between the axilla and the pisiform bone in 40 formaldehyde solution fixed upper limb specimens and 10 fresh upper limb specimens were carefully dissected, observed and measured. According to the observation, the entry path was designed and endoscopic operation was performed, in which full length ulnar nerve was isolated and exposed via endoscope. Whether the ulnar nerve and its adjacent structures were injured or not was observed postoperation openly.ResultsThe ulnar nerve lay superficially in the middle part of the upper arm, elbow and the middle and distal part of the forearm. It coursed with the brachial artery, superior ulnar collateral artery in the upper arm and with ulnar artery in the forearm. The ulnar nerve gave off branches on the level of elbow and the distal part of forearm mostly and invariably. It was easy to isolate and expose the ulnar nerve endoscopically, and there was no distinct injury of vessels or nerves by observation openly postoperation.ConclusionThe location of ulnar nerve is fairly fixed between the middle part of the upper arm and the level of wrist, descending through intermuscular loose connective tissue. The ulnar nerve gives off branches fairly concentrated with unconspicuous variations and its accompanying vessels such as superior ulnar collateral artery and ulnar artery are identified and protected easily, which make it easy to perform endoscopic surgical operation. The endoscopic incisions can be made in the middle part of upper arm, the ulnar groove in the elbow and the middle and distal part of forearm.II. Anatomical study of endoscopic surgical entry pathof the median nerveObjectiveTo study the anatomic adjacent structures, branch course and concomitant vessels of the median nerve and design the surgical entry path and the key point of operation for clinical endoscopic harvesting of the median nerve.Materials and methodsThe course, branches, adjacent structures and surface signs of the median nerves between the axilla and the carpal tunnel in 40 formaldehyde solution fixed upper limb specimens and 10 fresh upper limb specimens were carefully dissected, observed and measured. According to the observation, the entry path was designed and endoscopic operation was performed, in which full length median nerve was isolated and exposed via endoscope. Whether the median nerve and its adjacent structures were injured or not was observed postoperation openly.ResultsThe median nerve lay superficially in the elbow and the middle and distal part of the forearm. It coursed with the brachial artery in the upper arm mainly. The median nerve gave off branches on the level of elbow and the proximal part of forearm mostly and invariably. It was easy to isolate and expose the median nerve endoscopically, and there was no distinct injury of vessels or nerves by observation openly postoperation.ConclusionThe location of median nerve is fairly fixed from the level above elbow to the wrist, descending through intermuscular loose connective tissue. The median nerve gives off branches fairly concentrated on the level of elbow with no important accompanying vessel, which makes it safe to perform endoscopic surgical operation. The median nerve lies superficial on the level of cubital fossa and the middle and distal part of forearm, where it can be dissected and exposed immediately by a small incision, which provides ideal entry for endoscopic surgery.Part three: Clinical ApplicationI. Clinical Application of Endoscopic Intervention in Improving the Treatment Outcome of Injured Peripheral NervesObjectiveTo apply endoscopic technique in early exploration and neurolysis of injured peripheral nerves, in early detection of nerve suture quality combining with NAP, and in electric stimulation during the operation.Materials and methodsNine patients with injured peripheral nerves (8 injured ulnar nerves and 1 injured median nerve) were involved in this study. With two 1.5-centimeter-long incisions, injured peripheral nerves went through exploration, neurolysis, electrophysiological detection and electric stimulation via endoscope. Postoperative patients were folio wed-up periodically to judge the treatment outcome.ResultsEndoscopic surgical operations were performed successfully on 6 out of 9 patients. Three patients (2 injured ulnar nerves and 1 injured median nerve) went through open surgery because of their highly proliferative scars in the suture site.The amplitude and nerve conduction velocity of NAP improved 30% and 9.8% respectively after the exploration and electric stimulation. The process of nerve regeneration and functional recovery obviously accelerated after the operation. Long-term follow-up showed effective functional recovery of injured peripheral nerves.ConclusionEndoscopic technique can be used in the early exploration of injured peripheral nerves. Combining with NAP detection, it can be applied in accurate judgement of nerve suture quality. Neurolysis and electric stimulation via endoscope can effectively improve the functional recovery of injured peripheral nerves. Besides, it is a valuable minimally invasive technique offering quick recovery.II. Harvest Full Length Ulnar Nerve by Means of Endoscope for Contralateral C7 Nerve Root Transfer in Treatment of BrachialPlexus InjuriesObjectiveOn the basis of the anatomical study of endoscopic surgical entry path of the ulnar nerve, to report the surgical procedure and its effect of harvesting full length ulnar nerve via endoscope for contralateral C7 nerve root transfer in treatment of brachial plexus injuries, which can avoid long scar formation.Materials and methods6 patients with total roots avulsion were randomly recruited in. Three small incisions were made in the mid upper arm, the ulnar groove on the level of elbow and 7cm proximal to the lentiform bone of wrist respectively, and the ulnar nerve and its dorsal branch were isolated and cut via endoscope with full length ulnar nerve taken out from the upper arm's incision. The surgical time was recorded, and the vascularity of the dissected ulnar nerve was observed during the operation. Then the ulnar nerve with blood vessel pedicle was transferred in the reverse direction through cross-chest subcutaneous tunnel to the uninjured side and anastomosed to contralateral C7 nerve. The recovery of the injured limb after the second-stage of contralateral C7 nerve root transfer was followed-up.ResultsThe full length ulnar nerves of these six patients were harvested successfully with endoscope. The full length of the incisions was 7cm to 8cm. The operation of...