**Region:** Chest and Shoulders # Thoracoacromial Artery Flap ## Anatomy - Pedicle: thoracoacromial artery — a short branch arising from the second part of the axillary artery; it passes around the upper border of pectoralis minor, pierces the clavipectoral (costocoracoid) fascia, and immediately divides into two main branches (pectoral and deltoid) and two smaller twigs (clavicular and acromial) (Angiosomes of the Torso). - Venae comitantes accompany the artery in its course (angiosome descriptions imply venous drainage with the axis). - Course to skin paddle: the deltoid branch passes laterally toward the deltoid and gives a septocutaneous perforator that emerges in or adjacent to the deltopectoral groove (this perforator is often large and supplies the skin over the deltopectoral groove/shoulder) (Angiosomes of the Torso). - Perforator pattern: a single large septocutaneous perforator from the deltoid branch in the deltopectoral groove is described as the key skin supply; beyond this point branches over the deltoid are predominantly musculocutaneous (Angiosomes of the Torso). - Choke vessels / adjacent angiosomes: the pectoral/deltoid territory anastomoses within muscle with the internal thoracic (mammary) and lateral thoracic systems; these connections allow capture of adjacent angiosome tissue (example: deltopectoral flap capturing deltoid territory via internal thoracic perforators) (Angiosomes of the Torso). - Nerves: no discrete thoracoacromial sensory or motor nerve branches to a skin paddle are described in the provided materials; neural anatomy for sensate transfer is not detailed in the attached sources. - Included tissues: skin and subcutaneous tissue over the deltopectoral groove and shoulder; muscular supply to pectoralis major/minor and deltoid is in the angiosome and can be included where indicated (musculocutaneous territory described). The pectoral branch supplies pectoralis minor and the deep surface of pectoralis major; the deltoid branch supplies the clavicular head of pectoralis major and the deltoid muscle (Angiosomes of the Torso). - Thickness / arc / variants: - Thickness profile and formal arc-of-rotation measures are not provided in the supplied sources. - Important anatomic variants: the size of the septocutaneous perforator is variable — it may be very large (offering a robust skin perforator) or smaller; there are meaningful anastomoses with adjacent systems (internal thoracic, lateral thoracic) that determine territory capture and must be considered when planning multiterritory flaps (Angiosomes of the Torso). - Notably, there are no significant cutaneous branches arising from the pectoral branch (i.e., skin over the sternum/medial chest is supplied by internal thoracic perforators rather than pectoral branch cutaneous twigs) (Angiosomes of the Torso). ## Dissection Steps 1. Positioning, markings, landmarks. - Patient position: supine (typical for deltopectoral/deltoid–pectoral flap harvest and inset to head/neck/chest); identify clavicle, deltopectoral groove, and the course of the intended skin paddle over the deltopectoral groove and shoulder (Angiosomes of the Torso). - Mark the course of the deltopectoral groove and the proposed skin island centered on the deltoid-branch perforator; preoperative localization of the septocutaneous perforator with a handheld Doppler is recommended to center the flap over the vessel (Angiosomes of the Torso; Supraclavicular and scapular flap chapters show the routine use of handheld Doppler to map cutaneous pedicles). 2. Plane (suprafascial/subfascial), perforator identification (handheld/IO Doppler). - Incise the skin island and proceed from distal to proximal (skin toward clavicle) in a subfascial plane keeping the fascia attached to the flap as appropriate for the vascular pattern described (Angiosomes of the Torso; analogous flap techniques in the supplied flap chapters describe subfascial elevation to protect perforators). - Use a handheld Doppler to confirm the location of the septocutaneous perforator as dissection approaches the deltopectoral groove; identify the perforator as it pierces the deep fascia (a distinct septocutaneous perforator is often palpable/visible in the deltopectoral groove) (Angiosomes of the Torso). 3. Pedicle dissection: exposure, control, division; transfer/inset; perfusion checks. - Once the septocutaneous perforator is identified, continue proximal dissection as needed to gain pedicle length. The main thoracoacromial trunk is short and typically nearby where it pierces clavipectoral fascia; the surgeon may skeletonize the deltoid branch/perforator to the origin if longer reach or larger caliber is required (the angiosome description emphasizes the short course of the trunk and the early branching) (Angiosomes of the Torso). - If the perforator encountered is exceptionally large and the flap spans three vascular territories (risking tip necrosis), a two-stage (surgical delay) approach is described historically: ligation of the large perforator and deferring definitive transfer for 1 week to allow choke anastomoses to dilate before completing transfer (this maneuver is specifically noted in reference to large perforators and three-territory flaps) (Angiosomes of the Torso). - Inset: orient the skin paddle according to recipient requirements; when the flap is raised on the thoracoacromial/deltoid branch perforator, the expected skin territory is the deltopectoral groove and adjacent shoulder/deltoid skin. - Perfusion checks: intraoperative handheld Doppler and gross clinical assessment of flap capillary refill/color are used; the supplied sources emphasize pre- and intraoperative Doppler mapping to ensure the pedicle is centered and patent (Supraclavicular; Angiosomes of the Torso). 4. Donor-site closure techniques. - Primary closure is commonly achievable for deltopectoral/deltoid-region donor sites when designed appropriately; if primary closure is not possible, skin grafting or staged closure/tissue expansion are options (parascapular/supraclavicular donor-site principles in the supplied material outline primary closure limits and grafting alternatives). - Scar orientation: design the axis of the flap to minimize a hypertrophic/stretched scar — the angiosome authors note that designing the flap parallel to natural skin lines/rib axes can result in superior scar appearance compared with placing the scar along the main axis of a large perforator (Angiosomes of the Torso). ## Indications and Contraindications - Indications: - Local pedicled deltopectoral / thoracoacromial flap for head and neck and shoulder resurfacing (historically used for deltopectoral flaps; cited examples include transfer to tip of shoulder and head/neck reconstructions) (Angiosomes of the Torso). - Reconstruction of skin and soft-tissue defects of the clavicular–deltoid region, anterior shoulder, and adjacent chest wall where the deltoid-branch septocutaneous perforator provides reliable skin supply (Angiosomes of the Torso). - Source for a perforator-based flap when a robust septocutaneous perforator is present (Angiosomes of the Torso). - Use as a component of composite reconstructions that exploit anastomotic capture of adjacent territories (internal thoracic / lateral thoracic connections) is anatomically supported. - Contraindications: - The provided sources do not list explicit absolute contraindications for thoracoacromial-based flaps. - Relative considerations in the supplied material for adjacent torso/axillary donor systems include prior axillary dissection or irradiation that may disrupt source vessels — such prior operations are noted elsewhere in the supplied flap texts as factors altering flap selection for adjacent donor systems (see scapular/parascapular flap discussion). Use of the thoracoacromial axis when its perforator is absent or nonviable (as identified by Doppler) would be ill-advised based on the mapping principles in the supplied material. ## Postoperative Care - Monitoring schedule / method: - The supplied sources emphasize the use of Doppler for intraoperative localization and confirmation of pedicle patency; no formal postoperative monitoring schedule for thoracoacromial flaps is provided in the attached materials. - Routine clinical monitoring (inspection, capillary refill, Doppler interrogation as available) is implied by the practice of Doppler mapping and intraoperative confirmation used in adjacent flap chapters. - Warming / antithrombotic practice / positioning / drains / mobilization / diet / analgesia: - Specific postoperative protocols (warming, anticoagulation, diet, analgesia) are not specified for thoracoacromial flaps in the provided texts. - Donor-site management: the general donor-site principles in the attached flap chapters (primary closure when possible; skin graft if necessary; consider drains for larger donor-sites) apply (parascapular/scapular chapters). - Return-to-OR thresholds and time windows: - No specific numeric time windows or thresholds for re-exploration after thoracoacromial flap transfer are provided in the attached sources. - A historical maneuver described for large perforators in multiterritory flaps is to delay definitive transfer for 1 week after ligation of a dominant perforator to allow choke anastomoses to dilate (Angiosomes of the Torso). ## Complications (rates & management) - Frequencies / rates: the supplied materials do not provide numeric complication rates for thoracoacromial/deltopectoral flaps. - Typical complications and management as described in the supplied sources: - Tip necrosis in multi-territory (three-territory) flaps: reported as a known problem when raising extensive three-territory flaps; the historical management described is to ligate a very large perforator and delay definitive transfer for 1 week to permit dilation of choke anastomoses prior to transfer (Angiosomes of the Torso). - Donor-site hypertrophic or stretched scarring: noted with certain flap axis orientations; management and prevention include designing the flap axis parallel to natural skin/rib axes (the authors recommend orienting the flap to connect to lateral intercostal perforators in a more favorable axis to reduce scar problems) (Angiosomes of the Torso). - Partial flap loss / distal tip ischemia: discussed conceptually in relation to territory capture and choke anastomoses; risk mitigation includes careful Doppler mapping, appropriate flap design, and use of surgical delay when indicated (Angiosomes of the Torso). - Infection, seroma, hematoma, fat necrosis: these are not quantified for thoracoacromial flaps in the supplied materials; general donor-site and flap care principles from adjacent chapters (drains when used, primary closure vs grafting) apply. - Management algorithms: - Large dominant perforator with risk of tip necrosis: ligate and stage (delay) definitive transfer for 1 week to allow choke vessel dilation (Angiosomes of the Torso). - If donor-site scar concerns: alter flap axis to align with rib-parallel lines (Angiosomes of the Torso). - No formal re-exploration thresholds or thrombolysis protocols are provided in the attached sources. ## Key Clinical Pearls - The thoracoacromial artery arises from the second part of the axillary artery, is short, passes around the upper border of pectoralis minor, pierces clavipectoral fascia, then divides into pectoral and deltoid branches (with clavicular and acromial twigs) — plan your dissection accordingly (Angiosomes of the Torso). - The deltoid branch commonly gives a single large septocutaneous perforator that emerges in the deltopectoral groove and is the principal skin supply for deltopectoral/deltoid-region flaps — locate and map it with a handheld Doppler preoperatively (Angiosomes of the Torso; Supraclavicular / Scapular chapters illustrate Doppler mapping practice). - The pectoral branch supplies pectoralis minor and the deep surface of pectoralis major and provides virtually no significant cutaneous branches — do not rely on pectoral branch cutaneous twigs for a skin paddle (Angiosomes of the Torso). - When a very large perforator is encountered and the planned flap extends across adjacent angiosomes (three-territory flap), consider a staged (surgical delay) strategy: ligate and defer definitive transfer for 1 week to allow choke anastomoses to dilate and reduce distal necrosis risk (Angiosomes of the Torso). - Design the donor scar axis to respect skin/tissue lines — the angiosome authors recommend orienting the flap axis to minimize hypertrophic or stretched scars (flap axis parallel to ribs/lateral intercostal perforators produced superior scars in their series) (Angiosomes of the Torso). - Use intraoperative and preoperative Doppler routinely to map the septocutaneous perforator and to confirm that the skin paddle is centered over the vascular entry point (technique affirmed across the supplied flap chapters). - If additional pedicle length or a larger-caliber inflow is required, recognize the thoracoacromial trunk is short; proximal control (or alternate pedicles) may be necessary — plan reconstructive strategy with awareness of the limited trunk length (Angiosomes of the Torso). - When harvesting composite or musculocutaneous components in the region, remember the thoracoacromial axis is intimately connected with internal thoracic and lateral thoracic anastomoses; these connections permit capture of adjacent tissue but also require careful planning for territory perfusion (Angiosomes of the Torso).