The Scapula, Transverse And Spinous Processes

The scapula is defined as a large triangular flattened bone lying over the ribs, posterior on either side, articulating laterally with the clavicle at the acromioclavicular joint and the humerus at the glenohumeral joint. It forms a functional joint with the chest wall, the scapulothoracic joint (Dirckx, 2001). Also known as the shoulder blade, unlike most bones of the body which serve as rigid spacers, is one of the few bones that act like "anchors" for soft tissues and other bones (Clay & Pounds, 2003). There are three groups of muscles that attach to the scapula. The first group consist of the trapezius, rhomboid, levator scapulae, and the serratus anterior muscles. These deal with stabilization and rotation of the scapula. The second group consists of the deltoid, biceps, and triceps muscles. The third group includes the muscles of the rotator cuff which consist of the subscapularis, the supraspinatus, infraspinatus, and teres minor muscles (Thibodaux & Patton, 2002). There are a few other roles the scapula plays in the functioning of the shoulder. The first is being a stable part of the glenohumeral articulation. This has to do with the ball-and-socket relationship the scapula has with the humerus and maintaining a coordinated relationship in terms of movement. The scapula is also involved in the retraction and protraction along the thoracic wall and the elevation of the acromion in certain movements for sports such as throwing or serving. These roles are important in acceleration and deceleration and avoiding impingement and caracoacromial arch compression during these types of movements (Kibler, 1998).

The spine contains a number of "back bones" called vertebrae. The vertebrae is made up of two laminae, two transverse processes, a spinous process, and four facets (Back, 2005). The transverse process is a bony protrusion on either side of the arch of a vertebrae, from the junction of the lamina and pedicle. The spinous process is the dorsal projection from the center of a vertebral