Nerve transplantation and nerve transfer

Peripheral nerve injuries are common in both normal and wartime situations. According to some of the war damage statistics of the Second World War, nerve damage in the extremities accounted for 10% of the total number of traumas. In firearm fractures, about 60% have nerve damage. Omer reported 22% of patients with upper limb injuries with peripheral nerve injury on the battlefield in Vietnam. Usually peripheral nerve injury accounts for about 1.5% to 4% of all trauma. Proper grasp of surgical indications and timing of surgery is the key to performing surgical treatment and achieving good results. The timing of repair after nerve injury is very important. In principle, the sooner the better, but time is not an absolute factor, and late repair can also achieve certain effects. Treatment of diseases: lower limb nerve injury hand nerve injury Indication Nerve transplantation and neurotransfer are suitable for: 1. The nerve defect is too large, and the method of overcoming the defect can not be used to achieve the end-to-end anastomosis. 2. Nerve defect with adjacent joint injury is strong or limited, and can not overcome the defect. If the nerve defect is too large, the method of free nerve and flexion joint can still not reach the tension-free anastomosis. The nerve metastasis or autologous nerve transplantation should be considered. Otherwise, the tension is too large or excessively flexed, and the suture is easy to be separated after operation. Or injury, or due to excessive traction caused by ischemic necrosis, nerve fiber tissue proliferation, can affect the recovery of nerve function. Surgical procedure Neurotransfer After hand injury, the residual nerve can be used to repair nerve damage of other fingers. In the upper limbs, such as the median nerve and the ulnar nerve at the same time in different planes of injury and defect, nerve graft should be repaired to repair the two nerves, but if the defect is too large, the two nerves cannot be repaired at the same time, and the longer ulnar nerve can be transferred to the proximal segment. The median nerve is sutured distally to restore the function of the median nerve. 2. Nerve transplantation In nerve transplantation, the autologous secondary cutaneous nerve is used to repair the finger nerve or other large nerves. Commonly used are the sural nerve, the saphenous nerve, the medial cutaneous nerve of the forearm, the lateral femoral cutaneous nerve and the superficial branch of the radial nerve. The most commonly used is the sural nerve. The above nerves are all about 2 to 3 mm in diameter. It is possible to use a nerve of 20 to 40 cm in length for transplantation. However, it is not possible to repair the ulnar nerve with the superficial branch of the ipsilateral sacral nerve to avoid excessive numbness in the hand. When several large nerves are simultaneously damaged, one of them can be used to repair other important nerves. For example, when the upper arm is injured, the median, ulnar, ankle, and musculocutaneous nerves have large defects. When the contralateral anastomosis cannot be performed, the ulnar nerve can be used to repair the median, musculocutaneous, and phrenic nerves. When the median nerve of the forearm and the ulnar nerve have large defects and can not be used as a contralateral anastomosis, the ulnar nerve graft can be used to repair the median nerve. In the lower limbs, when the sciatic nerve defect is too large to be repaired, the phrenic nerve can be separated from the common sacral nerve, and the phrenic nerve can be repaired by the common peroneal nerve graft. There are several methods for nerve transplantation, which can be selected according to specific conditions. (1) Single-strand nerve free transplantation method: The nerve used for transplantation is close to the nerve thickness to be repaired. If the finger nerve is repaired by the cutaneous nerve or the residual finger nerve, the nerve outer membrane suture method can be used to suture the transplanted nerve and the outer membrane of the repair nerve. The length of the transplant nerve should be slightly longer than the length of the nerve defect to be repaired, so that after repair There is no tension at the suture. (2) Cable-type nerve free transplantation method: If the nerve used for transplantation is thin, several cutaneous nerves must be combined to repair the defected nerve. When repairing, the transplanted nerve is first cut into multiple segments, and the epicardium is sutured so that the thickness is close to the affected nerve and then sutured with the nerve to be repaired. (3) Transplantation between nerve bundles: performed under a surgical microscope. The technique of operation is the same as that of nerve bundle suture. First, the outer membrane of the two ends of the nerve is excised 1 to 2 cm, the corresponding nerve bundle is separated, the scar tissue of the nerve bundle is removed to the normal part, and then the transplanted nerve bundle is placed between the corresponding nerve bundles to make a bundle. Stitching. (4) nerve pedicle transplantation: after a thin nerve graft, generally does not cause nerve necrosis. When a large nerve is used for transplantation, nerve-centered necrosis often occurs due to ischemia of the free segment of the nerve, resulting in scarring between the bundles and affecting the effect. If the median nerve and the ulnar nerve are simultaneously broken, the defect is too large to be repaired, and the median nerve can be repaired with the ulnar nerve. The median nerve and the proximal segment of the ulnar nerve were removed and end-to-end anastomosis was performed. The ulnar nerve was proximally cut and the blood vessels were retained as much as possible. After 6 weeks, the free ulnar nerve was sutured to the distal segment of the median nerve. (5) Free vascular grafting with vascular pedicle: multiple use of the sural nerve with small saphenous vein for free transplantation. The small saphenous vein is anastomosed to the well-known artery adjacent to the repair nerve, so that the nerve of the transplanted segment can obtain blood supply, which is beneficial to nerve regeneration.