We identified 89 studies from our initial search. Only 11 of the articles provided a description of the technique involving the use of the pectoralis major muscle flap in the reconstruction of the sternoclavicular defects. Five (5) of the articles were excluded because they described the exact same procedures that has been previously described by a different author.
Case 1
The pectoralis major muscle advancement flap (Fig. 2a): The use of this flap for sternoclavicular defect reconstruction was first described by Munoz et al. in 1996 [15] and its modification, total release of humeral attachments by Opoku et al. in 2019 [16]. In this procedure, a flap consisting of skin and subcutaneous tissue is raised starting from an incision in the midline sternum. The extent of the flap is the deltopectoral groove. The pectoralis muscle flap is then raised from the chest wall to it attachment to the humerus making sure not to injure the TAA. This is done from medial to lateral chest wall. The muscle flap is then mobilized in a supero-medial vector to cover the sternoclavicular joint defect. If more length and muscle bulk is desired, the pectoralis muscle can be detached form it’s attachment to the humerus. In this configuration, the muscle is not split, none of the major branches of the Thoracoacromial artery is sacrificed, however, the pectoral perforator of the internal mammary are sacrificed.
Case 2
Split pectoralis major muscle flap (Fig. 2b): First described by Zehr et al. in 1996 [1].
The SCJ defect is evaluated and the flap is planned. A flap consisting of skin and subcutaneous tissue is raised in a medial to lateral dissection. This dissection exposes the underlying pectoralis major muscle. An incision is made in the upper one-half of the pectoralis muscle at the lateral most aspect of the exposure. The fibers of the muscle are then divided in a longitudinal manner in the direction of the muscle’s origin on the sternum. The flap can then be rotated about 45 to 60 degrees to cover the SCJ defect. This configuration has ample muscle for soft tissue coverage. It is well vascularized from the intact sternal perforators of the IMA. The TAA is sacrificed.
Case 3
Partial pectoralis major muscle advancement flap (Fig. 2c): First described by Song et al. in 2002 [17].
After SCJ resection, A flap consisting of skin and subcutaneous tissue is raised in the mid-sternum starting at the manubrium and carried caudally. The superior one third of the underlying pectoralis muscle is separated from the chest wall in a medial to lateral direction as far as the deltopectoral groove. The clavicular ant sternal attachments of the muscle is then released. The medial intercostal perforators are divided in the process. The muscle is then advanced medially to cover the SCJ defect. The resulting flap is a large flap with robust blood supply dependent on the TAA. The sternal perforators are sacrificed.
Case 4
The islandized hemipectoralis major muscle flap (Fig. 2d): First described by Schulman et al. in 2007 [10]. After SCJ resection, a flap consisting of skin and subcutaneous tissue is raised exposing the pectoralis major muscle. The pectoralis is split at the demarcation between the clavicular and sternal portions. The muscle attachment to the clavicle and sternum are divided. The resulting clavicular portion of the PM muscle is reflected superiorly to expose the thoracoacromial artery. The muscle is then divided lateral to the TAA. This results in a clavicular portion of the PM that is completely islandized based on the TAA. The muscle is advanced supero-medially to fill the defect. This configuration has a small to moderate amount of muscle dependent on the TAA. It has a robust blood supply.
Case 5
Deltoid branch-based clavicular head of pectoralis major muscle flap (Fig. 2e): First described by Al-Mufarrej et al. in 2013 [18]. It is basically a partial islandized pectoralis flap based on just the deltoid branch of the TAA. The branches of the TAA are not sacrificed.
After SCJ resection, the TAA is meticulously dissected out. The plane separating the clavicular and sternocostal portions of the PM is identified. The muscle is the split along this plane. The TAA pedicle and its branches are identified. The muscle fibers of the clavicular head of the PM are divided lateral to the pedicle. The artery is re-identified. The acromial branch of the deltoid artery can be divided to improve the muscle flap arc of rotation. Lateral to medial dissection in the subpectoral plane is performed as well as release of any sternal attachments. Once the muscle is islandized, the flap is used to cover the SCJ defect.