Reconstruction of Trochanteric Pressure Sores using Extended Double Folding Tensor Fascia Lata Flap
Tensor fascia lata (TFL) flap and its modifications are commonly used for trochanteric sore coverage. TFL flap has a small volume of muscle on its proximal portion but is just a thin fasciocutaneous flap on its distal portion. If the TFL flap does not have a sufficient amount of soft tissue, the pressure sore can recur because the covering flap will progressively atrophy. The angiosome of the lateral femoral circumflex artery, which is the dominant pedicle of TFL muscle and its fascia, is distributed up to several centimeters above to the knee. Thus, the skin territory of the TFL flap could be safely extended to the lateral condyle of the femur. Accordingly, we used an extended double folding TFL flap in order to cover the sore with a large amount of soft tissue.
We designed the extended TFL flap in a V-shaped pattern (Fig.1). The anterior border of the flap was marked by drawing a line from the anterior superior iliac spine to the lateral condyle of the femur. The posterior border was marked from the center of the greater trochanter to the lateral condyle of the femur. After debridement of the sore, including ostectomy of the greater trochanter, a skin incision was made along the anterior and posterior borders just above the fascia lata in depth. The fascia lata was incised about 1 cm lateral to the anterior or posterior border to widen the pedicle of the flap and to improve the blood supply of the distal portion of the flap. The TFL flap was elevated by undermining the subfascial plane. The entire distal portion of the flap, except the proximal portion for covering the defect, was de-epithelialized. The de-epithelialized distal tip was tangentially removed until pin-point bleeding was shown on the bed of the flap to ensure a rich blood supply. When the TFL flap was transposed into the defect, the distal de-epithelialized portion was double folded to pad the defect cavity. Finally, the trochanteric defect was covered with a thickness of soft tissue comprising three layers of the flap. The dog-ear on the proximal area of the flap was corrected by excising only the skin preserving the subcutaneous tissue. The donor site was always closed primarily.
Eleven trochanteric pressure sores of nine patients were reconstructed using this method without any surgical complications. There were no recurrences during follow-up (6-22 months). All flaps had a sufficient thickness of the soft tissue over the previous greater trochanter, even as its bulkiness decreased over time (Fig.2).
Thus,
the double folding TFL flap has sufficient soft tissue bulkiness and a reliable
blood supply. This method provides a good option for covering trochanteric
pressure sores.
Fig.1. Surgical procedure for extended double folding Tensor Fascia Lata flap. (Above left) Flap design in the V-shaped pattern. (Above right) Flap elevation after formation of wide fascial pedicle and de-epithelialization of the distal portion of the flap. (Below left) Covering the defect with the three-layer structure made by double folding the flap. ( Below right) Postoperative view after correcting the dog-ear deformity.
Fig. 2. Cases. (Left) Preoperative view of trochanteric pressure sore in two different patients (above and below). (Right) Postoperative view. These flaps had a sufficient bulkiness even 8 months (above) and 22 months (below) after reconstruction.