• Thoracic Limb
  • Thoracic girdle
  • Arm
  • Forearm
    • Radius
    • Ulna
  • Forepaw
• Pelvic Limb
  • Pelvic girdle
  • Thigh
  • Leg
    • Tibia
    • Fibula
  • Hindpaw
• Vertebral Column
  • Vertebrae
  • Ribs
  • Sternum
• Skull
  • Introduction
  • Braincase
  • Facial bones
  • Cavities of skull
  • Quizzes

 

Thoracic Limb

Forearm (Antebrachium)

Radius: The proximal extremity consists of head, neck, and tuberosity.  The head of the radius proximally forms an oval, depressed articular surface, the fovea capitis, which articulates with the capitulum and part of the trochlea of the Humerus.  On the medial border of the bone and distal to the neck lies the radial tuberosity for insertion of biceps brachii and brachialis muscles. The body of the radius is compressed so that it possesses cranial and caudal surfaces and medial and lateral borders.  The trochlea is the distal extremity of the radius.  The ulnar notch provide articulation with the ulna on the lateral side of the distal extremity. The medial surface of the trochlea ends in a rounded projection, the styloid process. 

Clinical correlation: All the various types of fractures can be seen involving either or both the radius and ulna.  Distal to the proximal third of the radius these bones usually fractures as a unit, but proximal to this region independent fractures of both bones are commonly seen.  The development of angulation and rotation at the fracture site; delayed union; and nonunion are not uncommon sequelae in distal third fractures. Measures to prevent them should be kept in mind constantly.