Anatomic variations of the median nerve in carpal tunnel release.

Carpal tunnel syndrome (CTS) is a well-known clinical entity. Release of the transverse carpal ligament is considered to be the treatment of choice. Both open and endoscopic release of the transverse carpal ligament in CTS has yielded satisfactory results. Although these procedures are very common in surgical practice, inadequate release and intraoperative damage to neural elements are very frustrating complication for both the patient and the surgeon. The purpose of this study was to demonstrate incidental intraoperative findings of variations of the standard median nerve anatomy. We obtained incidental intraoperative identification of median nerve variations in 110 consecutive patients operated with open release of the transverse carpal ligament in CTS. Using the Amadio classification, we found intraoperatively variations of median nerve at the wrist in 11 patients. In three patients, there was an aberrant sensory branch arising from the ulnar side of the median nerve and piercing the ulnar margin of the transverse carpal ligament. Neural variations arising from the ulnar aspect of the median nerve were common and could be a cause of iatrogenic injury during endoscopic or open release. Surgeons should be aware of anomalous branches, which should be recognized and separately decompressed if needed.

Brachial plexus root avulsions.

The majority of adult brachial plexus palsies are posttraumatic injuries caused by high-energy forces, usually involving motor vehicles. In infants, brachial plexus palsies commonly represent obstetrical injuries following excessive traction on the plexus during complex or difficult delivery. Most adult injuries, and occasionally those in infants, represent brachial plexus root avulsion injuries that carry serious ramifications from the standpoint of permanent disability of a paralyzed extremity, prolonged recuperation, and significant socioeconomic impact. Modern-day management of root avulsions should focus on early, aggressive microsurgical reconstruction of the brachial plexus, combining various neurotizations with intraplexus and extraplexus ipsilateral and contralateral nerve donors, utilization of vascularized nerve grafts, and finally the use of free vascularized and neurotized muscles. When these multistage microsurgical management techniques are applied early (with complete avulsions) they may often result in significant return of neurologic function, especially in young patients. Amputation should be looked upon as an option only when these newer microsurgery techniques have failed.

Outcomes of brachial plexus reconstruction in 204 patients with devastating paralysis.

Thus far, devastating injuries of the adult brachial plexus have had a poor prognosis. This article presents the possible outcomes of aggressive microsurgical reconstruction in the largest series of patients in North America to date. It should change the pessimistic outlook that has surrounded these lesions. In this study, the outcomes of surgery were analyzed in relation to the type and level of injury, the age of the patient, and the denervation time; stronger donors for neurotization in relation to the various targets were delineated. The results were analyzed in 204 patients with adequate follow-up from a total of 263 patients who were operated on between 1978 and 1996. The mean age of the patients was 25.9 years, and the injuries were caused by high-velocity motor accidents involving avulsion in 55 percent of the patients. Nerve reconstruction included 577 nerve repairs (140 direct neurotizations and 437 cases of nerve grafting). Microneurolysis was performed in 89 cases. Vascularized nerve grafts were used in 120 repairs. Muscle transfers (29 pedicled and 78 free) were used to enhance function. The results were good or excellent in 75 percent of suprascapular nerve reconstructions, 40 percent of deltoid reconstructions, 48 percent of biceps reconstructions, 30 percent of triceps reconstructions, 35 percent of finger-flexion reconstructions, and 15 percent of finger-extension reconstructions. The majority of the patients had protective sensation and pain relief postoperatively.

Optimal time for distraction osteogenesis in limbs with nerve repairs: experimental study in the rat.

The optimal period of time between peripheral-nerve repair and initiation of limb lengthening procedures has never been precisely determined. In the clinical setting, the surgeon must decide how long the repaired nerves should be allowed to heal before subjecting them to the forces created by the limb-lengthening process. The authors designed a study to quantify and qualify the effects of different recovery periods between initial nerve repair and subsequent limb-lengthening via distraction osteogenesis. Forty-two Sprague-Dawley male rats were randomized in two different categories of nerve repair: end-to-end and nerve grafts. At 4, 8 and 12 weeks after nerve reconstruction, the femur was submitted to limb-lengthening at a rate of 1 mm/day (0.25 mm every 6 hr). Sciatic Function Index (SFI) evaluation indicated that the impact of distraction was detrimental in the grafted nerves, although they maintained their electrical and morphologic properties at comparable levels to the non-distracted nerves. Nerves with direct coaptation presented an overall superior regeneration pattern. The findings in end-to-end repairs distracted at 8 weeks and those of grafted nerves at 12 weeks were comparable to those in distracted normal nerves. The morphology of the distracted nerves appeared to be more organized than that observed in the non-distracted nerves.

Effect of distraction osteogenesis on the peripheral nerve: experimental study in the rat.

Distraction osteogenesis is the current method of choice for bone lengthening. Despite the gain in experience, various complications are reported, among them, adverse effects on peripheral-nerve function. In order to thoroughly investigate the effect of distraction on neural tissue, a distraction osteogenesis model in the rat was established, using the femur of 30 Sprague-Dawley rats. The animals were randomized in three groups, following different rates of distraction (0.5 mm, 1.0 mm, and 1.5 mm/day) for 50, 25, and 16 days, respectively, so that the final length of distraction was the same in all groups. The mean sciatic function index ranged near normal in all groups. All groups demonstrated decrease of conduction velocity and the area under the curve of the compound action potential, while morphologic alterations consisted of decrease in the number of axons and evidence of active degeneration. Animals in Groups 1 (0.5 mm/day) and 2 (1 mm/day) displayed comparable changes, while in Group 3 animals (1.5 mm/day), changes were significantly more adversely dramatic. The safest and fastest rate of distraction in this rat model was determined to be 1 mm/day.

Nonviable injuries of the tibia.

Management of severe open fractures and non-viable injuries of the tibia remain both difficult and controversial. The orthopedist must carefully assess the injured limb in order to determine whether it should be salvaged or amputated. The difficult operative procedure requires thorough knowledge of microsurgical techniques necessary to repair vascular and neural injury. Over a 10 year period, 13 patients with non-viable, open fractures of the tibia underwent limb salvaging attempts using identical treatment protocol. 5 of the 13 limbs were salvaged, while 8 limbs were later amputated, because of either failure of revascularization or severe infection. 2 patients died; one with good circulation in the limb because of a massive pulmonary embolism 5 days postoperatively and the other because of severe septicemia 13 days postoperatively.

Open type IIIB and IIIC fractures treated by an orthopaedic microsurgical team.

An orthopaedic team with an extensive microsurgical background treated 46 patients with open fractures, 22 Type IIIB and 24 IIIC, of the upper and lower extremities during the past 10 years. All 24 patients with Type IIIC fractures and 12 with IIIB fractures had associated arterial injuries. In all patients from both categories, an effort was made to revascularize the limbs using microsurgical techniques and to stabilize the fractures as early as possible. Of the Type IIIC fractures, 16 were in the lower extremity and 8 in the upper extremity. Of the Type IIIB injuries, 8 were in the lower and 14 in the upper extremity. Of the limbs with Type IIIC fractures, 13 (54.2%) were salvaged and 11 (45.8%) were amputated. The latter was related to the proportionally high number of tibial fractures (13 of 24), 8 of which were amputated. None of the patients with Type IIIB injuries underwent amputation. These results suggest that limb salvage in Type IIIB and, particularly, Type IIIC injuries was associated with the application of microsurgical techniques to restore complete (Type IIIC) and incomplete (Type IIIB) ischemia. The number of amputations in Type IIIC fractures was attributed to the open tibial injuries, which are reported to have an amputation rate ranging from 60% to 100%.

[A case of multifocal neurinoma of the femoral nerve associated with chronic myeloblastic dysplasia]. / Un cas de neurinome étagé ancien du nerf crural, associé à une dysplasie myéloblastique chronique.

A large multiple lobulated painless mass in the inguinal fossa, was investigated and removed, in a 58 years old patient with undiagnosed chronic myelodysplasia. The patient was initially referred to the urologic clinics for recurrent bleeding from the urinary tract, when the above mentioned and few smaller masses were palpated on the anterior aspect of the thigh. Clinical, laboratory and imaging investigation revealed enlargement of the spleen and the liver accompanied by relatively large and well separated tumors under the inguinal ligament extending to the upper thigh. From clinical history the patient had recurrent episodes of spontaneous bleeding from the nose and the bladder. He underwent open biopsy under general anesthesia where the inguinal tumor was found to be well encapsulated, firmly attached to a branch of the femoral nerve and loosely connected with the next mass that had similar characteristics. Intraoperative decision was made to excise the entire lesion which consisted of thirteen lobules of varying size, connected to each other as a chain. Histological examination revealed multifocal ancient neurilemona from a sensory branch of the femoral nerve. Further investigation of the patient for the episodes of hemorrhage and the enlargement of the spleen and the liver gave the diagnosis of chronic myelodysplasia. The patient was doing well one year after the excision of the tumor, and had an area with hypoesthesia above the knee. The concurrence of the two distinct neoplasms is discussed.