Loss of factor XIIIa in pig dermis during tissue expansion.

Considerable evidence suggests that factor XIIIa, a blood coagulation factor, also functions in tissue repair, and specifically in the dynamic process of fibroplasia. On the other hand, the dynamic process of tissue expansion would require a loosening of the dermis, the opposite of fibroplasia. We examined the effects of tissue expansion on the expression of factor XIIIa in pig skin. Standard immunohistochemical procedures were used coupled with a rabbit antibody to factor XIIIa. In this report, we demonstrate that the normal expression of factor XIIIa in pig dermis is completely inhibited at the apex overlying the tissue expander. Factor XIIIa inhibition during expansion supports the thesis that this substance is important in the production and maintenance of fibroplasia.

Recurrent squamous-cell carcinoma arising in pilonidal sinus tract--multiple flap reconstructions. Report of a case.

Squamous-cell carcinoma arising from a pilonidal sinus tract is an unusual complication of a common condition. Approximately 36 cases of carcinoma related to pilonidal disease have been reported in the literature. Wide excision with tumor-free margins has yielded five-year disease-free states in 55 percent of patients. Recurrence rates have been 44 percent to 50 percent in several large series. Regional (inguinal) nodal metastasis occurs in 14 percent of patients, heralding a dismal prognosis. Radiation and chemotherapy are of minimal palliative value. Reconstruction of these patients has consisted of split-thickness skin grafts or local cutaneous and myocutaneous flaps. Some authors have allowed healing by secondary intention. A case of squamous-cell carcinoma arising in a chronic pilonidal sinus tract is reported. Local recurrence required an extensive resection resulting in a large sacral/perineal defect. A single-stage reconstruction of this defect with multiple muscle and musculocutaneous flaps is described.

Desmoid tumors of the head and neck.

Desmoid tumors of the head and neck are uncommon and associated with a posttreatment recurrence rate as high as 70 percent. This study was undertaken to determine cure rates achievable by surgery and radiotherapy and the factors influencing failure. A chart review of all patients at our institution with desmoid tumors of the head and neck from 1919 to 1982 was undertaken, and pertinent data were tabulated. Forty-eight patients were found with this problem. Average duration of symptoms was 1.6 years, and tumor size ranged from 1 to 12 cm (mean 5.1 cm). Average follow-up was 5.8 years. The most common site of occurrence was the neck (34 patients). Thirty-two patients underwent complete excision with 8 recurrences; 4 were reexcised with no further recurrence at last follow-up. Fourteen patients had incomplete excision with 12 recurrences. Radiotherapy was employed as the primary therapy in two patients; both experienced recurrence. Complete excision is the only effective treatment for desmoid tumors of the head and neck, resulting in a disease-free state in 75 percent of the patients (87 percent after reexcision). Involvement of the brachial plexus was the chief factor precluding complete excision. Radiotherapy was of very little value.

Monitoring muscle viability using evoked M waves.

The experiments described reveal the direct relationship between blood flow and evoked electrical activity in muscle flaps. It is demonstrated that monitoring of EMWs will detect vascular occlusion to a muscle flap within 1 hour. Detecting failure this soon provides the surgeon an opportunity for reexploration and salvage of a muscle flap before irreversible change has occurred. Correlations with observed muscle contraction and intramuscular temperature changes are also made.