Thorax
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
An 87-year-old woman had a complete removal of a breast (mastectomy) and the adjacent axillary lymph node to remove a cancerous tumour. She says that since the surgery she has had difficulty raising her arm above horizontal to brush her hair. Injury to which of the following structures is the most likely cause of this patient’s longstanding problem?Suprascapular nerve.Axillary nerve.Long thoracic nerve.Pectoralis major muscle.Pectoralis minor muscle.
Tissue coverage for exposed vascular reconstructions (grafts)
Sachinder Singh Hans, Mark F. Conrad in Vascular and Endovascular Complications, 2021
The pectoralis major muscle originates from the anterior aspect of the medial half of the clavicle; muscle fibers arising from here pass transversely and are often separated from the rest of the muscle by a slight gap. Additional muscle fibers originate from the anterior surface of the sternum, from the cartilages of all the true ribs, and from the aponeurosis of the abdominal external oblique muscle. These muscle fibers converge toward its insertion on the humerus and travel in a superolateral direction. It is the largest and most superficial muscle of the anterior chest wall. There is generous blood supply to the pectoralis major, with the myocutaneous flap based upon the thoracoacromial artery, a branch directly off the axillary artery. Additional blood supply arises medially from the internal mammary artery and laterally from the long thoracic artery, branches of which are generally sacrificed during elevation of the flap to secure adequate pedicle length.18
Upper Limb
Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno in Understanding Human Anatomy and Pathology, 2018
The pectoralis major and pectoralis minor have similar evolutionary and developmental origins, being innervated by the lateral pectoral nerve and the medial pectoral nerve. Pectoralis major, being larger, is innervated by both nerves, while the smaller pectoralis minor is innervated only by the medial pectoral nerve. The pectoralis major has a clavicular head, a sternocostal head, and an abdominal head. In anatomical position, the pectoralis major lies mainly anterior and medial to its insertion point onto the humerus, so its contraction adducts and flexes the arm. As its insertion is onto the lateral lip of the intertubercular groove, on the anterior surface of the humerus, it also medially (internally) rotates the arm. Because the pectoralis minor originates from ribs 3-5 and runs superiorly and posteriorly to insert onto the coracoid process of the scapula, its contraction causes the protraction and depression of the scapula. The deep fascia on the surface of the pectoralis major is called pectoral fascia, and it is continuous with the axillary fascia. Between the pectoralis major and the deltoid lies the deltopectoral triangle and the cephalic vein, which pierces the clavipectoral fascia and passes through the costocoracoid membrane (Plate 4.5b).
Post-operative complications of salvage total laryngectomy forpost-radiotherapy recurrent laryngeal cancer using pectoralis major myocutaneous flaps
Published in Acta Oto-Laryngologica, 2019
Isaku Okamoto, Kiyoaki Tsukahara, Akira Shimizu, Hiroki Sato
The PMMC flap was harvested by a board-certified head and neck surgeon, from the side contralateral to the dominant hand. The form of the skin of the PMMC flap was designed to allow plication in a single-stage operation (Figure 1). The following briefly describes how the PMMC flap was harvested and applied (Figure 2). We first designed the skin flap and confirmed the outer edge of the pectoralis major muscle after making the incision. Next, we separated the rear surface of the pectoralis major muscle and confirmed pulsation and location of the thoracoacromial artery (nutritive blood vessel). The pectoralis major muscle was separated gently from the chest wall to prevent damage. While confirming the thoracoacromial artery and giving a margin of safety of around 2 cm, we separated the pectoralis major muscle toward the clavicle, as the pivot point. After raising, the PMMC flap was transferred to the neck via the supraclavicular route. Between 7 and 10 days after surgery, swallowing videofluorography (VF) was performed to ensure that no suture failure was present, then oral diet was initiated.
Everything pectoralis major: from repair to transfer
Published in The Physician and Sportsmedicine, 2020
Kamali Thompson, Young Kwon, Evan Flatow, Laith Jazrawi, Eric Strauss, Michael Alaia
The pectoralis major is a triangular muscle that lies anterior to the subscapularis and coracobrachialis and inferior to the deltoid [30]. It contains two heads: the superior clavicular head and the inferior sternocostal head. The clavicular head originates at the anterior border of the medial half of the clavicle, from which the fibers run laterally in a downward direction. It is innervated by the lateral pectoral nerve (C5-C7), which exits the lateral cord of the brachial plexus medial to the pectoralis minor, travels with the pectoral branch of thoracoacromial artery, and enters the pectoralis major at a mean of 12.5 cm medial to the humeral insertion (95% confidence interval 10–14.9 cm) [4,30,31]. The primary role of the clavicular head is forward flexion, adduction, and internal rotation of the humerus. The clavicular head is also partially responsible for abduction once the arm is abducted to 90° and adduction with the arm below 90°.
Muscle flaps for sternoclavicular joint septic arthritis
Published in Journal of Plastic Surgery and Hand Surgery, 2021
Barkat Ali, Timothy R. Petersen, Anil Shetty, Christopher Demas, Jess D. Schwartz
Important anatomical considerations at the time of resection and debridement of the SC joint are knowledge of the vascular pedicle and its innervation. The vascular pedicle to the central sternocostal segment of the pectoralis major muscle is the inferior, pectoral branch of the thoracoacromial artery which proximally runs deep to the muscle. Preservation of this blood supply is important for future reconstruction [11]. Innervation of the pectoralis major muscle is dual; medial and lateral pectoral nerves. This is important to avoid denervation of the sternocostal segment during elevation of the clavicular head [12]. There are studies describing different configurations of pectoralis major muscle, but in our series all patients received rotation advancement without release of the humeral head in case of ipsilateral flaps and with release in case of contralateral flaps [13–15]. Use of pectoralis major muscle flap after complete detachment of its origin and insertion has also been described [16].
Related Knowledge Centers
- Breast
- Lateral Pectoral Nerve
- Medial Pectoral Nerve
- Costal Cartilage
- Rib Cage
- Muscle Architecture
- Pectoral Muscles
- Pectoralis Minor
- Abdominal External Oblique Muscle
- Bicipital Groove