The serratus anterior muscle is a large muscle arising from the first to the ninth ribs. The lower three slips arising from the seventh, eighth, and ninth ribs lend themselves to transplantation because of their accessibility and relatively independent nerve and blood supply. The muscle provides a block of tissue that can be used as a vascular filler for a variety of defects using one, two, or three slips, depending on the size of the defect.1-3 It has proven particularly useful in coverage problems of the wrist, hand, head, and neck.4-8

The three lowest slips of serratus also provide an excellent dynamic transplant for use in facial paralysis.2 One or two of these slips can be used to replace small-muscle function in the hand or other muscles in the forearm. The serratus is flat and lends itself to multiple splitting because of its anatomic conFIGuration. The nerve and blood supplies enter the junction at the middle and posterior third of the muscle so that the anterior two thirds of the muscle can be split without compromising the blood supply or nerve supply to the individual slips. 2,3,4,9

Technical Considerations

The key landmarks are the same as for the latissimus dissection. The underlying anterior border of the latissimus muscle is identified. Under the lower portion of the latissimus, the serratus and external oblique muscles interdigitate and must be separated sharply. Once the origins of the ninth, eighth, and seventh slips have been cleared and identified, the remainder of the dissection is mainly mobilizing the neurovascular pedicle.

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