V2Chung OT in Flaps in Plastic and Reconstructive Surgery 97

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Operative Techniques in Plastic Surgery: Flaps

T E C H N I Q U E S ■ Flap Elevation Flap Design

■ If additional flap bulk is desired, a subfascial dissec- tion may be desirable and may incorporate a fascial extension beyond the borders of the skin paddle. ■ Paralyzing agents are used to facilitate electrocautery dissection. ■ As the superior border of the teres major is approached, a tenotomy is used to expose the border of the muscle until the cutaneous perforator to the skin paddle is identified. ■ The cutaneous perforator is followed proximally to the main trunk of the circumflex scapular vessels. ■ As the vessels are traced, distinct branches will be identified that directly penetrate the lateral scapular border or that travel closely along the muscle and fas- cia overlying the lateral scapular border ( TECH FIG 2B ). ■ Usually, the circumflex scapular artery sends two or three branches directly to the lateral scapular bone ( TECH FIG 2C ). ■ A transverse branch investing the overlying scapular mus- cle and fascia supplies the medial scapular border and may serve as the basis for a medial scapular osteocutaneous flap. ■ We tie this branch off and prefer to use the lateral bor- der of the scapula for reconstruction. ■ Distinct, descending branches of the circumflex scapu- lar vessels travel along the lateral border of the scapula and are identified and preserved ( TECH FIG 2D ). ■ At this point, the remainder of the skin paddle is elevated cephalad to the cutaneous branches of the circumflex scapular vessels. ■ The skin paddle is now completely free and perfused only by these cutaneous branches ( TECH FIG 2E ). This enables the skin to be moved back and forth to facili- tate exposure of the lateral scapular border. ■ The skin paddle can be rested on a stack of green tow- els to help expose the scapular border while minimiz- ing tension on the circumflex scapular vessels. ■ The teres minor and portions of the teres major and infraspinatus muscles are dissected off the lateral border of the scapula in order to prepare the bone for osteotomy. ■ A thin cuff of muscle is left on the lateral bone in order to preserve its periosteal blood supply.

■ Landmarks: lateral scapular border, teres major, teres minor, long head of triceps ■ The skin paddle of the flap is designed around the trian- gular fossa through which the circumflex scapular artery passes. ■ A depression superior to the teres major can usually be palpated and used to identify the triangular fossa ( TECH FIG 1A ). ■ The teres major measures two fingerbreadths wide and runs almost parallel to the lateral scapular border. ■ If the muscle cannot be palpated, then the lateral bor- der of the scapula may be identified and traced just proximal to the glenohumeral joint. ■ The triangular fossa is located two fingerbreadths medial to this junction of the lateral scapular border and glenohumeral joint. ■ Confirmation can be performed with a pencil Doppler. ■ A skin paddle 5 to 10 cm in width and 16 to 46 cm in length can be harvested and enable primary closure ( TECH FIG 1B ). ■ Cadaver studies have demonstrated that branches of the circumflex scapular artery emerge radially from the triangular fossa and even perfuse the anterior chest wall at least as far as the anterior axillary line. 6 The implication is that a long skin paddle can be harvested and followed into the inframammary fold to keep the donor site discrete. ■ Once the patient is prepped and draped in a sterile fash- ion, skin cuts are made along the outline of the elliptical skin paddle. ■ The skin paddle is elevated from caudad to cephalad using electrocautery ( TECH FIG 2A ). ■ Elevation can be performed in a subfascial or supra- fascial manner.

Soft Tissue Dissection

TECH FIG 1 • A. The triangular fossa, where the cutaneous branch of the circumflex scapular artery emerges, can be identified on physical examination. The teres major is pinched cephalad to the latissimus. The depression superior to the teres major is where the cutaneous branch emerges and can be confirmed with Doppler. B. The skin paddle to be elevated is outlined based on the course of the circumflex scapular artery. The scapula is palpated and the lateral border is marked.

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