15734

Muscle, myocutaneous, or fasciocutaneous flap; trunk

CPT code 15734 describes a complex reconstructive surgical procedure utilizing a muscle, myocutaneous (muscle and skin), or fasciocutaneous (fascia and skin) flap to repair a significant soft tissue defect located on the trunk. The trunk encompasses the thorax, abdomen, back, and flanks. This procedure is typically indicated for patients who have experienced substantial tissue loss due to severe trauma, extensive oncologic resection (such as radical excisions of malignant melanomas or sarcomas), deep pressure ulcers (commonly sacral, ischial, or trochanteric ulcers in non-ambulatory patients), radiation-induced tissue necrosis, or severe infections resulting in wide debridement. The procedure involves the surgeon carefully planning the flap design based on the defect's size, depth, and anatomical location, ensuring that a robust blood supply via a specific vascular pedicle is maintained or established. During the operation, the provider first prepares the recipient site by excising any necrotic, infected, or scarred tissue to create a healthy wound bed. Next, the donor flap is meticulously elevated from its native site. If it is a muscle flap, only the muscle is taken; if myocutaneous, the overlying skin and subcutaneous tissue are included; if fasciocutaneous, the deep fascia, subcutaneous tissue, and skin are elevated. The flap remains attached to its primary blood supply (the pedicle) to ensure tissue viability. The flap is then rotated, advanced, or transposed into the recipient defect. Once appropriately positioned, the surgeon performs an inset of the flap, securing it with multiple layers of sutures or staples to eliminate dead space and promote primary healing. Finally, the donor site is addressed. In many cases, the donor site can be closed primarily by undermining and advancing the surrounding tissue; however, if the donor defect is too large, an additional skin graft (reported separately) may be required to achieve complete closure. Closed suction drains are frequently placed in both the recipient and donor sites to prevent hematoma and seroma formation. This code reflects the high level of surgical expertise required to successfully transfer vascularized tissue, representing a critical intervention for limb and organ salvage, and restoration of anatomical form and function.

Clinical Indications

  • Stage III or Stage IV pressure ulcers of the trunk, such as sacral or ischial ulcers, requiring robust and vascularized tissue coverage.
  • Large surgical defects following radical oncological resection of the trunk, including sarcomas and large melanomas.
  • Extensive soft tissue loss secondary to severe trauma, avulsion injuries, or deep burns on the thorax, abdomen, or back.
  • Tissue necrosis resulting from radiation therapy requiring healthy vascularized tissue for adequate healing.
  • Deep sternal wound infections or mediastinitis requiring muscle flap coverage, such as a pectoralis major flap.
  • Dehiscence of abdominal or thoracic surgical wounds needing reinforcement with healthy, well-perfused tissue.

Procedure Steps

  1. Thorough evaluation and precise measurement of the recipient trunk defect to determine the required flap size and optimal donor site.
  2. Preparation of the recipient site through meticulous debridement of necrotic, infected, or devitalized tissue until healthy, bleeding margins are achieved.
  3. Incision and elevation of the planned muscle, myocutaneous, or fasciocutaneous flap while carefully identifying and preserving its critical vascular pedicle.
  4. Mobilization of the flap, ensuring adequate reach without placing undue tension, kinking, or twisting on the blood supply.
  5. Transfer of the flap into the recipient defect via rotation, advancement, or transposition techniques.
  6. Careful inset of the flap into the defect using layered sutures to close dead space and achieve a secure, tension-free closure.
  7. Placement of closed-suction drains in the dependent areas of both the recipient and donor sites to manage postoperative fluid accumulation.
  8. Primary closure of the donor site defect with layered sutures, or preparation of the site for a separate skin grafting procedure if primary closure is anatomically impossible.
  9. Application of appropriate postoperative dressings to protect the surgical sites and support the newly transferred flap without compressing the pedicle.

Coding Guidelines

  • CPT code 15734 includes the elevation, transfer, and inset of the flap, as well as the primary closure of the donor site. Do not bill primary closure of the donor site separately.
  • If the donor site requires a free skin graft or an adjacent tissue transfer for closure due to size, these procedures may be reported separately with the appropriate CPT codes (e.g., 15100, 15200).
  • Extensive debridement of the recipient site or excision of a tumor prior to flap coverage is typically reported separately. Use modifier 51 on the flap code if performed during the same surgical session by the same provider.
  • Do not report 15734 in conjunction with adjacent tissue transfer codes (14000-14302) when treating the same defect.
  • If the flap requires a delayed division of the pedicle or secondary inset, these subsequent procedures are reported separately utilizing modifier 58 for a staged or related procedure.
  • Code 15734 is anatomically specific to the trunk. Use distinct codes for flaps located on the head and neck (15733), upper extremity (15736), or lower extremity (15738).

Associated ICD-10 Codes