Summer Anatomy Lab July 25, 2013 Jennifer Klok Local Hand Flaps Summer Anatomy Lab July 25, 2013 Jennifer Klok

Reconstructive Ladder Healing by secondary intention Primary closure Skin graft Local flap Regional flap Free flap

Cross-Finger Flap Design: Vascular supply: Skin and subcutanous tissue Designed over dorsal aspect middle phalynx Vascular supply: Dorsal digital artery Digital perforators

Cross-Finger Flap Clinical Applications Coverage of volar aspect of adjacent digits’ middle phalangeal area Distal digital tip coverage Volar oblique fingertip amputations with exposed bone or tendon

Anatomy Dorsal Digital Artery (1mm) Dorsal skin distal to the distal proximal phalynx depends on perforating branches from digital arteries Course through Cleland’s ligament Supplies the flap Digital Perforators passing dorsally around finger (0.2- 0.3mm) The vascular supply of the dorsal skin distal to the distal portion of the proximal phalynx depends on perforating vessels from the digital arteries. These dorsal branches supply the flap. The perforating vessels course through Cleland’s ligament and anterior dorsal network, where they support a rich dermal and subdermal plexus. This supplies a laterally based cross-finger flap. There are two to four perforators over the proximal phalynx, midportion of the middle phalynx and distal third of the middle phalynx

Design and Markings Designed with base adjacent to injured finger Proximal and distal flap marked transversely Connect these with a longitudinal line just dorsal to mid-axis of dorsum of finger 3-sided rectangle Incisions made to encompass whole surface of middle phalynx

Volar finger defects

Dissection Incise skin based on markings down to SC fat until loose areolar plane Elevate flap in this plane, taking care to leave the paratenon behind Dissect to Cleland’s ligament; may need to divide ligament to increase pedicle length Cover donor site with skin graft Inset flap Divide flap 2-3 weeks later

Fingertip Defects

Reverse Cross-Finger Flap For adjacent dorsal digital wound coverage Elevate flap in subdermal plane Adipofascial flap to cover dorsal defect

Thenar Flap To cover defects on the index and long fingers Green’s: “Use where preservation of length is considered important and other techniques that have less potential for complications are not applicable”

Thenar Flap

Thenar Flap Donor site found by taking tip of index or ring finger and placing it against thenar eminance Draw circle around area of contact Draw H or curved incision at this point Elevate flaps in subcutaneous plane Inset flap Divide in 10-14 days For the H flap, the proximal flap covers the finger defect and distal flap advanced to cover donor

Points about the Thenar Flap To avoid potential for joint stiffness or unsightly scar in donor area: Design flap near the MP crease of the thumb; avoid the midpalmar area Fully flex the MP joint with whatever amount of flexion is required in the IP joints of the recipient finger Detach pedicle 10-14 days post-op and start immediate AROM To avoid the potential for joint stiffness with a permanent flexion contracture or unsightly scar in the donor area, one must keep in mind the three cardinal technical principles outlined by Melone and colleagues[70]: (1) design the flap near the metacarpophalangeal (MP) crease of the thumb and avoid the midpalmar area; (2) fully flex the MP joint with whatever amount of flexion is required in the IP joints of the recipient finger; and (3) detach the pedicle 10 to 14 days postoperatively and begin immediate active range of motion. Contraindications to either the cross-finger flap or the thenar flap would be any general condition that might lead to finger stiffness, such as rheumatoid arthritis, Dupuytren's contracture, any connective tissue disease involving the hand, and advanced age with its concomitant degenerative changes. Complications seem to be more prevalent in those patients older than 30 years of age with a greater tendency for the development of joint stiffness. We believe that the risk of this complication is a relative contraindication to the use of the thenar flap in patients older than age 30.

First Dorsal Metacarpal Artery Flap Classification: Type A fasciocutaneous flap From dorsal skin over proximal phalynx (FDMA) Clinical Applications: For defects in the thumb

FDMA Dominant Pedicle: Minor Pedicle: Nerve Supply: First dorsal metacarpal artery (FDMA) Minor Pedicle: Cutaneous perforators of the FDMA Nerve Supply: Dorsal sensory branches of the radial and ulnar nerves

Anatomy Dorsal metacarpal arteries From dorsal carpal arch formed from dorsal carpal arteries Gives rise to 4 dorsal metacarpal arteries These course over dorsal interosseous muscles Communicates with deep palmar arch Proximal to web space divides into 2 dorsal digital branches Then divide into terminal branches midway along proximal phalynx The dorsal carpal arch is formed from dorsal carpal arteries arising from the ulnar and radial arteries. The vessels anastamose across the dorsum of the distal carpal row to form a vascular arcade that gives rise to four dorsal metacarpal arteries. Each metacarpal vessel courses distally over the dorsal interosseous muscle bellies to supply the skin and subcutaneous tissues covering the dorsum of each finger and its adjacent dorsal web space. The first dorsal metacarpal artery (FDMA) tends to be a discrete terminal branch of the radial artery rather than arising directly from that dorsal carpal arch. The fifth dorsal metacarpal artery may also arise as a terminal branch of the ulnar artery. From its origin, each vessel courses distally toward the web space and communicates through the interosseous space with the deep palmar arch. Proximal to the web space, each of the second, third and fourth dorsal metacarpal arteries divide into two dorsal digital branches, on to each adjacent side of the index, middle, ring and little fingers. The FDMA supplies the dorsum of the thumb and radial side of the index finger, and the fifth dorsal metacarpal artery supplies the ulnar side of the little finger. Traveling distally along each side of the finger, the vessels divide into terminal branches midway along the proximal phalynx. The vessels supply the dorsal skin of the finger as far as the proximal interphalangeal (PIP) joint. Distally, the dorsal skin is supplies by branches of the palmar digital arteries.

Anatomy The first dorsal metacarpal artery (FDMA) tends to be a discrete terminal branch of the radial artery rather than arising directly from that dorsal carpal arch Found in the first intermetacarpal space, just distal to the extensor pollicis longus tendon Supplies the dorsum of the thumb and radial side of the index finger

Flap Markings From MCP joint to the PIP joint of index Radial & ulnar borders 1st the midlateral lines on either side of digit

Flap Dissection Incision in 1st dorsal web space, down to FDMA Elevate flap distal to proximal, just above paratenon Fascia and fat adjacent to 2nd metacarpal kept intact to protect vessels Transfer and inset flap Cover donor with skin graft An incision is then made in the dorsal first web space, and dissection is carried down to the first dorsal metacarpal artery, which arises from the radial artery. With a very complete dissection, a pedicle of 7 to 8 cm can be created. The flap is then incised and elevated at the level of the paratenon from a distal to proximal direction. Fascia adjacent to the second metacarpal along with adjacent fat are kept intact along the course of the vessels. A subcutaneous tunnel is created from the donor site to the recipient site, and the flap is brought through, with care taken not to kink or twist the pedicle. The dorsal proximal phalanx is covered with a full-thickness skin graft