**Region:** Chest and Shoulders # Dorsal Scapular Artery Flap ## Anatomy - Pedicle: dorsal scapular artery (DSA) as the deep branch of the transverse cervical/posterior scapular system; origin variable (may arise independently from the subclavian or from the transverse cervical trunk). The DSA courses posteriorly deep to/through brachial plexus branches, under levator scapulae and omohyoid, runs near the medial superior angle of the scapula where it divides into deep and superficial branches. Superficial branch pierces rhomboideus and runs on the deep belly of inferior trapezius, giving one or two musculocutaneous perforators to skin (cutaneous perforator consistently present) (Angrigiani; Taylor). - Typical pedicle length for tunneled dorsal scapular island flap: long leash reported (DSAP pedicle reported 15–16 cm) and flap pedicle can be dissected more proximally if needed (Angrigiani). - Venous drainage: variable; no consistent single accompanying vein proximally—venous anatomy variable and should be identified intraoperatively (Angrigiani). - Note: circumflex scapular system is a separate axis (circumflex scapular artery 2.5–3.5 mm external diameter; circumflex scapular length ~3–4 cm; subscapular artery divides after an average 2.2 cm) — do not confuse the DSA flap with scapular/parascapular flaps based on the circumflex scapular artery (Hanasono et al.; Taylor). - Course from origin to skin paddle: - Origin variable from subclavian or transverse cervical trunk → posterior course beneath/through posterior neck structures → superficial branch pierces rhomboideus at superomedial scapular angle → travels to deep surface of lower trapezius and issues perforators to skin over medial back (Angrigiani; Taylor). - Perforator pattern: - One to two consistent cutaneous perforators from the superficial branch of DSA through the lower trapezius to the overlying skin; perforator emergence usually at a point about 6–8 cm inferior to the spine of the scapula and ~8–9 cm lateral to midline (i.e., intersection of those lines commonly locates the perforator) (Angrigiani). - Flap sizes commonly reported: safe harvest 20 × 20 cm; clinical examples: 25 × 12 cm with long leash (Angrigiani). DSAP can include an osseous branch to medial scapular border when bone is required (Angrigiani). - Choke vessels / adjacent angiosomes: - DSA connects to adjacent posterior intercostal, dorsal scapular and circumflex scapular networks around the scapula; rich anastomoses exist around scapular blade (Taylor). Tunnelized flap uses this reliable cutaneous supply and benefits from the regional anastomotic network. - Nerves: - Cutaneous sensation to back: dorsal rami of spinal nerves; scapular/parascapular cutaneous flaps are typically not transferred as sensate flaps (Lee & Lin). - Motor: dorsal scapular nerve (innervates rhomboideus) lies close to vascular branch—care required during dissection to avoid rhomboid motor loss when harvesting DSAP with muscle-sparing technique (Angrigiani). - Included tissues: - Skin and subcutaneous tissue (primary), deep fascia retained with flap as needed. - Muscle-sparing harvest possible: small cuff or minimal portion of inferior trapezius may be included for perforator support without major functional deficit (Angrigiani). - Bone: medial border or tip of scapula can be harvested as vascularized bone based on the deep branch of the DSA (osseous branches to medial scapular border) — bone thickness limited compared with fibula; scapular tip bone typically thin and less suitable for implants (Angrigiani; Hanasono et al.). - Thickness profile: back skin variable by patient habitus; flap can be relatively thin in lean patients; thinning maneuvers available but may compromise vascularity (Lee & Lin). - Arc of rotation: - When tunneled under trapezius and supraclavicular region, DSAP can reach anterior neck, cheek, mid-sternum and calvarium; reported reach includes anterior thoracic wall, anterior neck and face (Angrigiani). Parascapular/scapular flaps (circumflex scapular angiosome) can be used as pedicled or free to reach head/neck/chest (Hanasono et al.; Taylor). ## Dissection Steps 1. Positioning, markings, landmarks. - Position: lateral decubitus for back access; ipsilateral arm prepped into field for mobility during dissection. For combined operations consider patient rotation as described for scapular/parascapular harvest (Hanasono et al.; Lee & Lin; Angrigiani). - Markings: palpate/mark medial border of scapula, spine of scapula, scapular tip, spinous processes/midline. For DSAP mark superomedial angle and expected perforator location: usually intersection of a horizontal line 6–8 cm inferior to scapular spine and a vertical line 8–9 cm lateral to midline (Angrigiani). For scapular/parascapular flaps mark triangular space (two-fifths from scapular spine to tip along lateral border) and flap axes (scapular transverse axis or parascapular vertical axis) (Hanasono et al.; Lee & Lin). - Confirm pedicle location with handheld Doppler preoperatively (recommended for circumflex scapular and parascapular flaps; DSAP perforator Doppler can be used but not mandatory) (Lee & Lin; Angrigiani). 2. Plane (suprafascial/subfascial), perforator identification (handheld/IO Doppler). - DSAP: incise skin margins and elevate in suprafascial/subfascial plane toward lateral trapezius border; identify perforator where it pierces trapezius/rhomboideus; Doppler may guide but direct subfascial dissection reliably reveals perforator (Angrigiani). - Scapular/parascapular: elevate in suprafascial plane toward triangular space; stay in loose subfascial areolar plane superficial to muscular aponeurosis to minimize bleeding; once pedicle reached, continue dissection deep to fascia for pedicle isolation (Hanasono et al.; Lee & Lin). 3. Pedicle dissection: exposure, control, division; transfer/inset; perfusion checks. - DSAP pedicle dissection: elevate flap to island on cutaneous perforator; bluntly dissect superficial branch off trapezius belly under magnification; trace through rhomboideus to identify deep branch and common trunk; ligate deep branch if not needed; bluntly enlarge anterior tunnel under trapezius/omohyoid/levator scapulae to permit pedicle passage to supraclavicular incision; deliver flap through tunnel and inset into defect (Angrigiani). Check pedicle for tension and kinking before final inset. - Scapular/parascapular pedicle (circumflex scapular): identify descending branch where it exits triangular space; ligate branches to muscles/periosteum if flap does not include bone; if additional length needed, dissect proximally to thoracodorsal or axillary artery for extended pedicle (Lee & Lin; Hanasono et al.). In osteocutaneous harvest, preserve musculoperiosteal branches to scapular lateral border and avoid osteotomy within 1 cm of glenoid fossa. - Perfusion checks: visual assessment, bleeding from flap edges, and handheld Doppler over pedicle; intraoperative adjustments if pedicle twisted or compressed (sources describe clinical checks but no mandated protocol). 4. Donor-site closure techniques. - DSAP: donor area usually closed primarily; place closed suction drain as indicated; post-op Velpeau dressing for 10 days to limit scapular movement and aid healing (Angrigiani). Reattach any divided muscle slips (e.g., partial rhomboid repairs) where necessary. - Scapular/parascapular: design width for primary closure (typical width 5–7 cm for scapular; parascapular up to 10 cm generally primary closed; flaps <8–9 cm closed primarily; larger defects may require graft or tissue expansion) (Hanasono et al.; Lee & Lin). Close as much donor site as possible before pedicle division to minimize ischemia; use closed suction drains; repair detached muscle origins to scapula and consider drill holes for reattachment if osseous harvest performed (Hanasono et al.). ## Indications and Contraindications - Indications: - Surface defects of head and neck, anterior neck, cheek, anterior thorax, calvarium (DSAP particularly useful when free tissue transfer unavailable or prior failed flap) (Angrigiani). - Reconstruction after prior radiation or scar where pedicled neck vessels may be compromised—DSAP pedicle usually outside irradiated field (Angrigiani). - Osseous reconstruction of mandible/continuity using medial scapular border when fibula not available (DSAP deep branch can supply medial scapular bone; Hanasono et al.). - Parascapular/scapular flaps: free or pedicled resurfacing for head/neck, axilla, chest, extremity; chimeric composites with latissimus/serratus/scapular bone available from subscapular system (Hanasono et al.; Lee & Lin). - Contraindications: - Absolute: none explicitly stated in sources for DSAP—relative contraindications include prior surgery or trauma that has disrupted the dorsal scapular pedicle or rhomboid/trapezius anatomy in that region. - Relative: significant vascular disease of the regional vessels, prior axillary dissection/radiation affecting intended pedicle course (for scapular/parascapular planning ipsilateral side may be avoided) (Hanasono et al.; Lee & Lin). Obesity causing excessively bulky flap (consider alternate donor or accept thickness limitations) (Lee & Lin). Preservation of dorsal scapular nerve recommended to avoid rhomboid dysfunction (Angrigiani). ## Postoperative Care - Monitoring schedule/method: - Clinical monitoring (hourly checks in immediate postop period) with assessment of color, capillary refill, temperature and turgor; handheld Doppler to confirm pedicle flow is commonly used intra/post-op for pedicled/tunneled flaps (sources describe Doppler use pre/intra-op; standard flap monitoring practices apply though specific hourly schedule not given). - No specific implantable probe protocols provided in the attached PDFs. - Warming, antithrombotic practice: - No specific pharmacologic thromboprophylaxis protocols for pedicled DSAP or scapular/parascapular flaps are specified in the texts; follow institutional microsurgical/free-flap protocols when applicable. - Positioning/splinting: - DSAP: Velpeau dressing for ~10 days to restrict scapular movement and protect pedicle (Angrigiani). - Scapular/parascapular: avoid tension on pedicle during positioning; ipsilateral arm available for manipulation during harvest—post-op range-of-motion exercises started within several days, normalization by 1 month reported (Hanasono et al.). Immobilize as required to prevent pedicle stretch. - Drains, mobilization, diet/analgesia: - Closed suction drains used at donor site (Hanasono et al.; Lee & Lin). Early gentle mobilization of shoulder recommended; routine postoperative analgesia and nutritional support per institutional standards. - Return-to-OR thresholds and time windows: - No specific time windows provided in PDFs. Standard flap practice: urgent return to OR for signs of vascular compromise (progressive pallor, darkening, absent Doppler signal, rapid swelling). For pedicled/tunneled flaps, relieve compression/twist immediately; for free flaps, re-exploration within first few hours often indicated. (Standard surgical judgment; specific numeric thresholds not provided in sources.) ## Complications (rates & management) - Reported rates: - The attached PDFs do not provide explicit complication rates (%) for DSAP, scapular, or parascapular flaps. Do not infer frequencies. (No numeric complication frequencies present.) - Typical complications and management (text-supported): - Venous congestion / arterial compromise: recognize clinically and address promptly—relief of kinking/compression in tunneled pedicle, return to OR for exploration if persistent; flap salvage maneuvers for pedicled flap include releasing tunnel, readjusting inset (Angrigiani; Hanasono et al.). Specific leeching/thrombolysis algorithms not detailed in the sources. - Partial/total flap loss: described as possible but no rates provided; management is surgical debridement and possible alternative reconstruction. - Infection: treat with antibiotics and drainage as needed. - Fat necrosis: possible in large flaps; no numeric rate provided. - Donor-site issues: seroma, hematoma, contour deformity and hypertrophic scarring (scapular/parascapular donor scars noted to stretch/hypertrophy if designed along main perforator axis—consider axis parallel to ribs to reduce scar visibility) (Taylor; Shokrollahi et al.). Primary closure usually possible; when grafting required, back graft take can be less reliable (Hanasono et al.). - Shoulder dysfunction: temporary loss of abduction reported up to 6 months after scapular/latissimus harvest in one source; DSAP when muscle-sparing preserves shoulder function but preserve dorsal scapular nerve to avoid rhomboid palsy (Hanasono et al.; Angrigiani). - Management algorithms (re-exploration, leeching, thrombolysis): - No stepwise algorithms or numeric time windows for re-exploration published in the provided PDFs for these specific flaps. Use standard microsurgical principles: urgent re-exploration for suspected vascular compromise, relieve compression, revise anastomosis or pedicle course, decompress tunnel for pedicled flaps; leech therapy or medicinal leeches may be used for venous congestion in appropriate settings though not specifically discussed in these chapters. ## Key Clinical Pearls - Locate and mark the triangular space and expected perforator preoperatively; for DSAP the perforator commonly lies at intersection: horizontal 6–8 cm inferior to scapular spine and vertical 8–9 cm lateral to midline (Angrigiani). - Preserve dorsal scapular nerve during dissection to avoid rhomboideus motor deficit—gentle elevation of lateral trapezius is critical (Angrigiani). - Tunnelization (DSAP) under trapezius/omohyoid/levator scapulae dramatically increases anterior reach—create a generous, nonconstricting tunnel and check for kinking before inset (Angrigiani). - When harvesting scapular/parascapular flaps, stay in the suprafascial/areolar plane superficially and convert to subfascial dissection once pedicle located; pedicle can be lengthened by proximal dissection to subscapular/thoracodorsal/axillary level (Lee & Lin; Hanasono et al.). - Design parascapular flap axis parallel to ribs (midaxillary line) when possible to reduce donor scar stretch and improve scar quality (Taylor). - Primary closure achievable for most donor defects if flap width limited (scapular 5–7 cm typical; parascapular often closed up to ~10 cm; flaps <8–9 cm typically closed primarily) — plan size accordingly (Hanasono et al.; Lee & Lin; Shokrollahi et al.). - If osseous reconstruction required, medial scapular border can be harvested on DSA deep branch but bone thickness is limited and less suitable for implant osseointegration than fibula; stop osteotomy at least 1 cm from glenoid/cavity when harvesting scapular lateral border (Hanasono et al.; Angrigiani).