The Appendicular skeleton 1.The pectoral girdle - clavicles - scapulae
2.The upper limb - arm - forearm - hand
The Appendicular skeletonThe appendicular skeleton is composed of 126
bones.The word appendicular is the adjective of the noun appendage, which itself means a part that is joined to something larger. Functionally it is involved in locomotion (lower limbs) of the axial skeleton and manipulation of objects in the environment (upper limbs).
1.The pectoral girdleThe pectoral girdle or shoulder girdle is the set
of bones which connects the upper limb to the axial skeleton on each side. It consists of the clavicle and scapulae
clavicles the clavicle or collarbone is a long bone that
serves as a strut between the scapula and the sternum. It is the only long bone in the body that lies horizontally.
It makes up part of the shoulder and the pectoral girdle ,
as it creates a bulge in the skin. It receives its name from the Latin: clavicula ("little key") because the bone rotates along its axis like a key when the shoulder is abducted.
The clavicles are slender, S-shaped bones that across the superior thorax on the anterior surface . The cone-shaped sternal end attaches to the manubrium medially, and the flattened acromial end articulates with the scapula laterally .
The medial two-thirds of the clavicle is convex anteriorly you can feel this anterior projection on yourself when you
palpate the clavicle. The lateral third is concave anteriorly
The superior surface is almost smooth, but the inferior surface is ridged and grooved for the ligaments and muscles that attach to it, many of which act to bind the clavicle to the rib cage and scapula.
scapulae the scapula from Greek meaning "to dig" or shoulder
blade, the bone that connects the humerus with the clavicle.
Like their connected bones the scapulae are paired, with the scapula on the left side of the body being roughly a mirror image of the right scapula.
The scapula forms the posterior located part of the shoulder girdle. , it is a flat bone, roughly triangular in shape, placed on a posterolateral aspect of the thoracic cage.
The primary function of the scapula is to attach the upper arm to the thorax, or trunk of the body.
This connection stabilizes the arm and provides for arm movement at the shoulder. The scapula, clavicle and humerus which make up the shoulder are inter-connected through a series of muscles, ligaments and tendons. Rotator cuff muscles connect the scapula to the head of the humerus bone forming the shoulder joint. This is a ball and socket type joint and is one of the most flexible joints in the body. It allows you to raise, lower, push, pull and rotate your arm.
2.The upper limbThirty bones form the skeleton of the
upper limb They are grouped into bones of the arm, forearm, and hand.
arm the arm is the upper limb of the body,
comprising regions between the shoulder and the elbow joints, and out to the fingers.
It can be divided into the upper arm the forearm and the hand
The humerus is the bone of the arm. It joins with the scapula above in the shoulder, at the glenohumeral joint and with the ulna and radius below at the elbow. The elbow joint is the hinge joint between the distal end of the humerus and the proximal ends of the radius and ulna. The humerus cannot be broken easily. Its strength allows it to handle loading up to 300 pounds (140 kg)
forearmThe forearm is the structure and distal region of
the upper limb, between the elbow and the wrist. The forearm contains two long bones, the radius and the ulna, forming the radioulnar joint.
The interosseous membrane connects these bones.
The forearm contains many muscles, including the flexors and digits, a flexor of the elbowthat turn the hand to face down or upwards, respectively.
handThe skeleton of the hand includes the bones of
the wrist and the bones of the metacarpus, and the phalanges, or bones of the fingers . The true wrist, is the proximal region of the hand, just distal to the wrist joint. The wrist contains eight marble-sized short bones, or carpals , closely united by ligaments.
The carpals are arranged in two irregular rows of four bones each In the proximal row, from lateral (thumb side) to medial, The carpals of the distal row, again from lateral to medial, are the trapezium .