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The early events associated with axonal growth into 10-mm nerve gaps were studied histologically in the rat sciatic nerve model to determine if the outgrowth of blood vessels, Schwann cells, and axons could be enhanced. In the first two experimental groups, collagen nerve guides were filled with either saline or Matrigel. Marrow-derived mesenchymal stem cells (MSCs) were added to Matrigel in two other groups, one of which contained cells transfected with VEGF (MSC/VEGF). After 21 days, the injury site was exposed, fixed, sectioned, and volume fractions of the conduit contents were determined by point counting. The bioresorbable collagen conduits appropriately guided the axons and vessels in a longitudinal direction. The volume fraction of axons was significantly greater in the group with saline when compared with all three groups with Matrigel. This measure had a significant positive correlation with actual counts of myelinated axons. The blood vessel volume fraction in the Matrigel group decreased compared with the saline group, but was restored in the MSC/VEGF group. All Matrigel groups had comparable cellularity and showed a distribution of residual Matrigel in acellular zones. The saline group, by contrast, sustained a network of delicate fibroblastic processes that compartmentalized the nerve and its natural matrix as it became infiltrated by axons as minifascicles. In conclusion, the reduction of axonal outgrowth in the Matrigel groups, when compared with the saline group, suggests that Matrigel may impede the early regenerative process even when enriched by the addition of MSCs or VEGF-transfected cells., ((c) 2008 Wiley-Liss, Inc.)

Preganglionic nerve root avulsion precludes sensory return, but motor regeneration is possible with sparing of motoneurons. The effect of GM-1 ganglioside treatment was studied with parallel evaluation of the autoimmune response. Rats (N=64) received injections of either GM-1 ganglioside or saline for 30 days following either C5 root avulsion or a hemilaminectomy control. The Bertelli grooming test assessed functional return. Before sacrifice at 5 months, serum was collected for enzyme-linked immunoabsorbent assay testing. Only 44% of the rats treated with ganglioside had a good functional outcome compared with 50% for controls. Although 17% of the rats developed anti GM-1 antibodies, there was no functional or histological evidence of neuropathy in any of the rats. We conclude that ganglioside treatment did not enhance recovery from peripheral nerve injury. Although an immune response was present in some rats, no overt signs of neuropathy were observed.

Purpose: Ulna longitudinal dysplasia is an uncommon congenital anomaly that demonstrates a wide variety of clinical manifestations. The clinical manifestations and function of patients with Bayne type IV ulna longitudinal dysplasia have not been well characterized. The purpose of this study was to report the clinical features of type IV ulna longitudinal dysplasia and the extent to which this affects a patient's ability to perform activities of daily living., Methods: The medical records of children diagnosed with ulna longitudinal dysplasia in our institution between 1960 and 2004 were reviewed. The children found to have ulna longitudinal dysplasia with radiohumeral synostosis (Bayne type IV ulna dysplasia) were studied. The laterality of the deformity, associated musculoskeletal and nonmusculoskeletal anomalies, and treatments were recorded. Patients were interviewed regarding their ability to perform activities of daily living., Results: One hundred twenty-five patients with 146 affected limbs were identified with ulna dysplasia. Seventeen limbs in 14 patients (12% of affected limbs) demonstrated radiohumeral synostosis (RHS). Three of 14 patients with RHS had bilateral involvement. The elbows were fixed in 20 degrees to 90 degrees of flexion. No elbows were positioned in full extension. Eleven of the 17 involved limbs with RHS had digital anomalies. Nine of the 17 limbs had surgical reconstruction. The majority of these procedures were performed on the hand., Conclusions: The elbow, forearm, wrist, and hand clinical findings associated with type IV ulna longitudinal dysplasia are variable. Surgical treatment usually focuses on correction of hand abnormalities. Many patients function satisfactorily and are able to perform daily activities without surgical intervention.