1. Humarus: The single and cylindrical bone from arm to elbow is called humerus. It is the first and largest bone of the forelimb. It consists of three parts. Head, body and neck. It has a round head on top. The head is inserted into the genoid cavity. There are two high tubercles (orbuds) on either side of the head. In the middle of it there is a groove or anatomical neck.
The body of the humerus is called the shaft. There is a high mound in its middle region. This is called deltoid ridge. At the lower end of the humerus is the epicondyle. Below the epicondyle lies the condyle. Condyle consists of capitulum and trochlea. Below the trochlea is the olicranon foramen.
2. Radius and Ulna: The two bones below the humerus are called Radius-Ulna. Of these, the outer bone is called the radius and the inner bone is called the ulna. The radius and ulna are connected by a membrane called the interosseous membrane. The upper part of both bones is covered by the annular membrane and the lower part by the antibrachial sheath. The radius consists of the head, neck and lobes at the top and the styloid process at the bottom. Again, the upper part of the ulna consists of the coronoid process, olecranon process, trochlear notch and tuberosity and the lower part the styloid process.
3. Carpal: There are 8 carpal bones, 4 each in two rows of the wrist. The upper row consists of 4 bones Scaphoid or Nevicular, Lunate, Triquetal and Pisiform. The lower row consists of 4 bones Trapezium, Trapezoid, Capitate and Hamate.
4. Metacarpal: Metacarpal unstable digit 5. Thumb, Index finger, Middle finger, Ring finger and Little finger. Each metacarpal bone consists of three parts. Head, body and base.
5. Phalanges: Finger bones are called phalanges. The phalanges are 14 in number. There are 2 bones in the thumb and 3 in the other fingers. Distal, Middle and Proximal. They are short and cylindrical bones.