|| The inferior incision is made first. A safe method for approaching the pedicle is to find the interval between the teres minor and teres major inferiorly and to follow it superiorly into the triangular space. Acland has observed that the appearance of the fascia of the teres minor is thick and white, while that of the teres major is somewhat thinner and red in color. This allows a reliable identification of the triangular space. Occasionally, the circumflex scapular artery may split and have a major branch running inferiorly. Once the pedicle has been identified, the cutaneous portion of the flap should be raised. Because of bleeding from the cut bone edges, harvesting the bone should be reserved for the last step. The dissection of the circumflex scapular artery and its two accompanying vena comitantes should be completed into the axilla before the osteotomy is performed. Also, before performing the osteotomy, the surgeon must expose the bone surfaces. With the electrocautery apparatus, the teres major is removed from its origin on the angle of the scapula. Because the bone's blood supply is periosteal, great care must be taken not to strip the periosteum. A portion of the teres minor must be sacrificed with the flap. With a periosteal elevator, the fibers of the teres minor are split longitudinally. Invariably, a large branch of the circumflex scapular artery that runs along the posterior surface of the scapula is transected to anastomose with the continuation of the suprascapular artery. This causes copious bleeding and should be ligated. The largest amount of bone that may be harvested includes the entire angle of the scapula extending superiorly to the neck of the glenoid. With an oscillating saw, the bone is then transected. The inferior portion of the bone flap is then lifted posteriorly to reveal the fibers of the origin of the subscapularis muscle.
These are carefully stripped extraperiosteally, with great care not to violate the periosteum. The final tether to be removed is the tendinous insertion of the long head of the triceps, which may be cut, freeing the bone. The bone flap thus obtained may be osteotomized as needed for specific applications.
It is imperative that all osteotomies be done subperiosteally, with minimal periosteal elevation. An ideal instrument to use is the Freer elevator. An assistant can hold two of these in place on either side of the bone, protecting the periosteum from the cutting instrument. Fine burrs or an oscillating saw may be used. Bone fixation can then be obtained with intramedullary Kirschner wires augmented with interosseous wires. A plate may be placed extraperiosteally along the flat, medial surface of the bone.
The technique for donor site closure is critical for both hemostasis and function. A small amount of bone wax can be used to limit the bleeding from the cut edge of the bone. Bleeding is most copious from the cancellous regions close to the neck of the glenoid. The blood loss is best controlled by closure of the muscles around the bone. The teres minor is sutured to the subscapularis with a strong, absorbable suture. This may be done as a running stitch to obtain a hemostatic closure. Next the teres major is sutured to the angle of the scapula and then the tendon of the long head of the triceps is reinserted under the neck of the glenoid.