ARM BONES -
Each arm contain 30 bones as : humerus in upper arm, radius ulna in forearm, 8 carples in wrist, 5 metacorples in plam, 14 phalnges in fingers.
Bone of upper arm. Head of humerus is fitted in glenoid cavity of scapula.
Ball and socket joint is formed.
Head bears a pair of small tuberosities, separated by intertubercular groove.
Trochlea is fitted in sigmoid notch of radius ulna.
A deltoid ridge is present at the anterior surface of humerus.
Above the trochlea supra trochlear foraman is present through which brachial artery passes out. Present in rabbit, but absent in man.
RADIUS ULNA -
Bone of fore arm. Ulna is longer than radius.
Radius is situated at thumb side. Olecranon process & sigmoid notch present at proximal end.
Note :- In frog radius & ulna both are fused in complete length, so the world radioulna is used instead of radius ulna.
In hand wrist, palm & fingers are clear. In wrist carpals bones are present.
In palm metacarpals are present. In fingers phalanges are present.
The digital formula of rabbit and man is 2 3 3 3 3 = 14.