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The coracoid bone is a bone in birds joining the sternum and shoulder-bone, and giving support to the wing. In mammals it is represented by the coracoid process of the scapula.
 Research Coracoid Bone
Scapulomancy (scapulimancy) is divination by reading the cracks which appear in a scapula (shoulder-blade) when it is roasted over an open fire. It was widely practised in ancient Babylon.
Research Scapulomancy
The acromion is the lateral projection from the spine of the scapula. The plough blade-like projection serves as a site of attachment for both the trapezius and deltoid muscles, which assist in giving the shoulder its strength during flexion.
Research Acromion
The arm is the upper limb in man, connected with the thorax or chest by means of the scapula or shoulder-blade, and the clavicle or collar-bone. It consists of three bones, the arm-bone (Humerus), and the two bones of the forearm (radius and ulna), and it is connected with the bones of the hand by the carpus or wrist. The head or upper end of the arm-bone fits into the hollow called the glenoid cavity of the scapula, so as to form a joint of the ball-and-socket kind, allowing great freedom of movement to the limb. The lower end of the humerus is broadened out by a projection on both the outer and inner sides (the outer and inner condyles), and has a pulley-like surface for articulating with the fore-arm to form the elbow-joint. This joint somewhat resembles a hinge, allowing of movement only in one direction. The ulna is the inner of the two bones of the fore-arm. It is largest at the upper end, where it has two processes, the coronoid and the olecranon, with a deep groove between to receive the humerus. The radius - the outer of the two bones - is small at the upper and expanded at the lower end, where it forms part of the wrist-joint. The muscles of the upper arm are either flexors or extensors, the former serving to bend the arm, the latter to straighten it by means of the elbow-joint. The main flexor is the biceps, the large muscle which may be seen standing out in front of the arm when a weight is raised. The chief opposing muscle of the biceps is the triceps. The muscles of the fore-arm are, besides flexors and extensors, pronators and supinators, the former turning the hand palm downwards, the latter turning it upwards. The same fundamental plan of structure exists in the limbs of all vertebrate animals.
Research Arm
The biceps brachii (biceps flexor cubiti) is a two-headed arm muscle that consists of the long head (caput longum), and the short head (caput breve). The long head originates from the supraglenoid tuberosity of the scapula and the short head originates from the coracoid process. The muscle extends from the shoulder to the elbow where the biceps tapers into a flat, strong tendon that inserts in the tuberosity on the upper end of the radius. It is innervated by the musculocutaneous nerves (5th and 6th crevical nerves) and is supplied by branches of the brachial artery. This muscle is the main flexor of the elbow joint. When working with other nearby muscles, it can also move the shoulder, since its upper ends are attached to the scapula. In addition it can twist the lower arm so that the palm faces outward, a movement called supination. The biceps and the triceps work together to control the up and down movement of the forearm.
Research Biceps Brachii
The conoid ligament is part of the coracoacromial ligament which extends from the base of the coracoid process to the conoid tubercle on the underside of the clavicle. It is responsible for controlling and regulating the gliding motions of the clavicle and the sternum, especially of the back and forth rotation of the scapula.
Research Conoid Ligament
The coracoacromial ligament connects the scapula with the clavicle. It has two parts, each of which regulates specific modes of movement: the trapezoid ligament and the conoid ligament.
Research Coracoacromial Ligament
The coracobrachialis or 'Casser's perforated muscle' is the smallest muscle in the upper arm region. It originates from the coracoid process of the scapula and inserts in the medial border of the humerus. The coracobrachialis is innervated by the musculocutaneous nerve and supplied by the brachial artery. This muscle is a somewhat superficial muscle and can be partially seen on the inside of the upper arm near the arm pit when the arm is raised. It runs alongside, but separate from, the short head of the biceps brachii. It flexes and adducts the arm at the shoulder joint.
Research Coracobrachialis
The coracoid process of the scapula is a short projection of bone from the neck of the scapula. This process serves as a site of attachment for the coracoacromial and coracoclavicular ligaments, the pectoralis major, the coracobrachialis, and the short head of biceps.
Research Coracoid Process
The deltoid is a large, thick powerful muscle with a triangular form and a coarse texture. The muscle is divided into three portions: an anterior (clavicular) portion, and acrominal portion, and a posterior portion. The anterior portion forms the broad side of the muscle and the posterior portion is located on the back of the shoulder. The muscle originates from the clavicle and from the spine of the scapula covering the outer side of the shoulder joint, giving the shoulder its rounded appearance, and inserts in the humerus. The deltoid is innervated by the 5th and 6th cervical nerves through the circumflex nerve and supplied by the circumflex artery.
Almost any movement of the shoulder and upper arm involves the deltoid muscle. The anterior portion is used to raise the arm from the body and to lower it again. The acrominal portion is a powerful abductor and the posterior portion is used to move the arm backward. It works with the pectoralis major to move the arm forward and works with the teres major and latissimus dorsi to move the arm back.
Research Deltoid
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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