Ariyan 1979 - PRS - Pectoralis Major Flap

Summary

This 1979 article by Dr. Stephan Ariyan describes the use of a new pectoralis major (PM) myocutaneous flap for head and neck reconstruction. The PM flap is based on the thoracoacromial artery and includes the overlying skin, allowing transfer of well-vascularized skin and muscle in one stage.

Anatomy and Blood Supply

• The PM muscle has horizontal fibers in the upper portion and oblique fibers in the lower portion.

• The main blood supply is from the thoracoacromial artery, with additional minor supply from other vessels.

• The thoracoacromial artery runs parallel to the muscle fibers in an oblique line from the acromion to the xiphoid, accompanied by the thoracoacromial vein and lateral pectoral nerve.

Surgical Technique

• The pectoralis major myocutaneous flap is harvested through an incision in the anterior chest just lateral to a line from the acromion to xiphoid process.

• The pectoral fascia is incised, the muscle fibers split, and the medial muscle elevated off the chest wall while preserving its axial neurovascular pedicle containing the thoracoacromial vessels and lateral pectoral nerve.

• For greater mobility, the lateral tendinous portion can be divided to create an island flap with intact circulation.

• The donor defect is closed by undermining and advancing the lateral chest tissues.

Case Examples

• 4 cases demonstrating orbital exenteration, oral cavity, and neck reconstruction.

• Skin paddles tailored for lining vs coverage as needed.

• Muscle provides bulk to obliterate dead space and support structures like mandible.

• One stage reconstruction possible.

Advantages Over Other Flaps

• More versatile than deltopectoral flap - narrower base, greater reach, doesn't require grafting.

• Provides skin, muscle bulk, and neurovascular pedicle in one stage.

• Excellent vascularity supports skin paddles even after radiation.

• May restore neck contour by replacing resected SCM.

• Closure is simpler with less donor site morbidity.

Conclusion The PM flap is felt to be very versatile for head and neck reconstruction based on excellent vascularity, bulk, reach, and low donor site morbidity. The author anticipates wide application for large oncologic defects.