British Journal of Plastic Surgery (1978), 31, 26-28 A COMBINED BICEPS AND SEMITENDINOSUS MUSCLE FLAP IN THE REPAIR OF ISCHIAL SORES By DANIEL C. BAKER, M.D., FRITZ E. BARTON, JR., M.D. and JOHN MARQUIS CONVERSE, M.D. The Eellevue Hospital Medical Center and Institute of Reconstructive Plastic Surgery, New York University Medical Center, 560 First Avenue, New York, N. Y. 100x5, USA IN large or recurrent ischial pressure sores with extensive bony involvement, scarring and absence of surrounding soft tissue, radical excision of all involved bone and soft tissue leaves a large space which Conway and Griffith (1956) recommended should be filled by a biceps femoris muscle flap before being covered with a large medially based posterior thigh rotation flap. We have occasionally found the biceps so atrophied in paraplegics that it was inadequate to fill the hole. Additional bulk may be obtained by rotating the semitendinosus together with the biceps. APPLIED ANATOMY The relevant anatomy of the hamstring muscles is shown in Figure I. The semi- membranosus does not contain any muscle fibres until the middle of the thigh and is unlikely to survive on a proximal vascular pedicle. The semitendinosus and the long head of the biceps have a common origin on the ischial tuberosity and are joined for approximately 5 cm before dividing to form separate muscle bellies. Their blood supply comes from perforating branches of the profunda femoris; there are usually 3 between which are extensive anastomoses (Testut and Latarjet, 1948). Fortunately the first perforator normally carries sufficient blood supply for both muscle bellies; occa- sionally the second perforator is important, and this can be readily determined by occluding it temporarily with a vascular clamp. TECHNIQUE Following total excision of the ulcer a standard posterior thigh flap is raised. The deep fascia is divided longitudinally and reflected. The muscles are then dissected and divided where they become tendinous below. They are then carefully freed upwards; the lowest perforator is divided; the middle is lightly clamped and, if no ischaemia develops, divided; the proximal perforator is preserved. The muscles must be free enough to allow rotation into the defect without tension. The skin flap is finally sutured in place. A typical case is shown in Figures 2 to 5. CONCLUSION Since the proximal perforator and its branches can support both the biceps femoris and semitendinosus muscle bellies, either or both may be used to fill the dead space in the repair of ischial sores. 26 THE REPAIR OF ISCHIAL SORES 27 Q uudrufus femDris _F~bular n. br. fo si7ort head of bkzeps fen. FIG. I. The anatomy of the hamstrings. 28 BRITISH JOURNAL OF PLASTIC SURGERY FIG. 2. A typical deeply undermined ischial sore. FIG. 3. The long medial based flap has been raised and the biceps femoris and the semitendinosus freed. The proximal perforator and its branches can be seen. FIG. 4. The muscles sutured to the ischial periosteum and fascia. FIG. 5. Six weeks postoperative. REFERENCES CONWAY, H. and GRIFFITH, B. H. (1956). Plastic surgery for closure of decubitus ulcers in patients with paraplegia. American Journal of Surgery, 91, 946. TESTUT, L. and LATARJET, A. (1948). Trait6 DAnatomie Humaine. Paris: G. Doin & Cie Editeurs.