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16. Support and Movement eLearn.Punjab

Pectoral Girdle and Fore Limb : Pectoral girdle comprises scapula, suprascapula, and clavicle.

The clavicle connects scapula with sternum.

The fore limb consists of humerus, radius and ulna, 8 carpals, 5 metacarpals and 14 phalanges.

Humerus forms ball and socket joint with scapula, while at distal end humerus forms hinge joint
with radius and ulna. The radius and the ulna at their distal end form multistage joint with eight
wrist bones called carpals. Five metacarpals form the framework of palm of the hand. Five rows of
the phalanges are attached to the metacarpals. They support the fingers.

Pelvic Girdle and Hind Limb : Pelvic girdle attaches the hind limb to the vertebral column (Fig

16.5). It consists of two coxal bones. Each is formed by the fusion of three bones ilium, ischium and
pubis. The pelvic girdle supports the pelvic region.

The hind-limb consists of 1 femur, 2 tibia and fibula, 7 tarsals 5 meta-tarsals and 14 phalanges.
Femur is the proximal bone which forms a hip joint with the hipbone, it is a ball and socket joint.
At the distal end, the femur forms knee joint with the proximal end of two parallel bones called
tibia and fibula. The distal end of the tibia and fibula forms a joint with seven tarsals, which are also
distally attached to five metatarsal bones of ankle. Five rows of the fourteen phalanges of the toes
are attached to metatarsals (Fig 16.5).

Joints

Joints occur where bones meet. They not only hold our skeleton together, but also give it the mobility.
Joints are classified on the basis of the amount of movement allowed by them, into three categories:
(i) Immovable joints (ii) Slightly movable joints (iii) Freely movable joints
The freely movable joints are of two types viz. hinge joint and ball and socket joint (Fig. 16.6)

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