Forearm Skeletal Anatomy: Radius and Ulna
Forearm Bone Identification
- The forearm consists of the radius and ulna.
- Radius: Located on the lateral side in the anatomical position.
- Ulna: Located on the medial side in the anatomical position.
- The bones are organized by their proximal end and distal end.
Features of the Radius and Rhenius
- Head of radius: Forms an articulation with the capyclum as part of the elbow joint; surrounded by the annular length of the ulna.
- Radial neck: The area located directly below the head of the rhenius.
- Radial tuberosity: A protrusion for tendon attachments.
- Styloid process in the radius: Distal point for tendon attachment.
Features of the Ulna
- Head and ulna: Located at the distal end, acting as an articular surface.
- Styloid process of ulna: A distal attachment point for muscle on the attachment, smaller than that of the radius.
- Olecranon process: Located on the posterior surface; sits in the olecranon fossa of the humerus.
- Orange notch: Located on the anterior side of the ulna to sit the trochlea of the uterus.
- Coronoid process: A bony projection jutting anteriorly for forearm muscle tendon attachment.
- Radial notch: Located at the proximal end; serves as the starting point for the annular ligament.
Connective Tissues and Articulations
- Interosseous membrane: A large structure made of fibrous tissue that separates forearm muscles into anterior and posterior components.
- Annular ligament: Starts from the radial notch of the ulna and surrounds the head of the radius.
- Angular ligament: Surrounds the head of the radius from the posterior side, starting from the radial notch.
- Proximal radial ulnar joint: Articulation point where the radius and ulna touch at the proximal end.
- Distal radial ulnar joint: Articulation point where the radius and ulna touch at the distal end.
- Together, these structures comprise the bones of the bone's valforum.