Improved axon diameter and myelin sheath thickness in facial nerve cable grafts wrapped in temporoparietal fascial flaps.

Injury to the facial nerve in the temporal bone presents a challenge to the recovery of nerve function, in that the fallopian canal in which it lies is poorly vascularized. This study was designed to determine if wrapping an intratemporal facial nerve defect repaired with a cable graft with a well-vascularized temporoparietal fascial (TPF) flap would improve facial nerve regeneration. To evaluate this question, a defect was created in the intratemporal left facial nerve of 10 rabbits. All nerves were repaired using cable grafts. In 5 animals, the nerve graft was wrapped with temporoparietal fascia, whereas in the other 5 rabbits it was not. Three additional animals underwent exposure only. The contralateral nerve served as a control in all animals. Quantitative analysis of the nerve graft 12 weeks after repair revealed greater recovery of original fiber diameter and myelin sheath thickness in TPF flap-wrapped repairs. Histological evidence of improved neural regeneration and functional nerve recovery was also seen in the repairs where the TPF flap was utilized. Nerve conduction and electromyographic studies of the cable-grafted nerve at 6 and 12 weeks were equivocal, however.

Pressure sores in the acute trauma patient: incidence and causes.

OBJECTIVES: The purpose of this review was to determine the incidence of pressure sores in acute trauma patients and to identify the causes. DESIGN AND MATERIALS AND METHODS: This study is a retrospective chart review of all acute trauma patients admitted to Harborview Medical Center between January of 1991 and December of 1993 who were discharged with an ICD-9 diagnosis of acute pressure sore. RESULTS: A total of 7,492 trauma patients were admitted. Thirty-two patients developed 44 pressure sores for an incidence of 0.4%. All of the patients were severely injured (mean Injury Severity Score, 21). Eighteen (41%) of the pressure sores developed as a result of unrelieved positional pressure. Thirteen (30%) of the pressure sores were equipment induced. CONCLUSION: Our incidence of pressure sores in acute trauma victims is very low and occurs in those most seriously injured. The majority of the wounds are due to unrelieved pressure from body positioning or equipment failure.