Elbow Forearm Wrist and Hand Elbow Bones Humerus
Elbow, Forearm, Wrist and Hand
Elbow Bones: – Humerus: only bone of the arm Landmarks: medial and lateral epicondyles, olecranon fossa, capitulum (articulation with the radius), trochlea (articulation with the ulna)
Ulna: bone on the pinkie (medial) side of forearm – Landmarks: olecranon process, radial notch Radius: bone on the thumb (lateral) side of forearm – Landmarks: radial head
Ligaments: – Ulnar collateral: prevents valgus force (think of it as MCL of knee) – Radial collateral: prevents varus force (think of it as LCL of knee) – Annular ligament: circular ligament encompassing the radius, allows for rotation of radius while holding it securely to the ulna
Bursae –Bicipital bursa: anterior aspect of elbow, cushions the bicep –Olecranon bursa: posterior aspect of elbow, cushions between olecranon process and the skin
Muscles – Elbow flexion Brachialis, brachioradialis, biceps brachii – Elbow extension Triceps brachii
Nerves: – Ulnar nerve: passes posterior to the medial epicondyle “hitting your funny bone”
Joint Mechanics – Elbow: hinge joint between ulna and humerus Allows for flexion and extension – Joint between ulna and radius (radio-ulnar) Allows for pronation and supination of the forearm
Forearm Bones: Radius and ulna held together by interosseus membrane – Landmarks: radial and ulnar styloid processes
Radioulnar joint –Proximal allows for pronation and supination –Distal connects the radius and ulna at the wrist
Muscles Anterior (flexors) – Flexor digitorum superficialis – Flexor digitorum profundus – Flexor carpi ulnaris – Flexor carpi radialis – Flexor pollicus longus – Pronator teres ** flexor tendons originate on the medial epicondyle of the humerus
Muscles cont. Posterior (extensors) – Extensor digitorum communis – Extensor carpi radialis longus – Extensor carpi radialis brevis – Extensor carpi ulnaris – Extensor pollicus longus ** extensors origiante on the lateral epicondyle of the humerus
Wrist and Hand Basic Anatomy – Bones Distal radius and ulna (styloid process) Carpals: 8 bones of wrist – Scapoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, hamate Metacarpals: 5 bones of hand Phalanges: 14 bones of fingers
Carpal tunnel: tunnel formed by carpal bones and closed off by the transverse carpal ligament. Nerves, blood vessels and muscles pass through this tunnel. Wrist joint: joint between distal radius and ulna and the carpal bones – Movements: flexion, extension, radial and ulnar deviation
Joints of Fingers and Hand Carpometacarpal joint (CM) Metacarpo-phalangeal (MP) Interphalangeal (IP) – Proximal Interphalangeal (PIP) – Distal Interphalangeal (DIP)
Ligaments of Wrist Ulnar collateral: from styloid process of wrist to triquetrum Radial collateral: from styloid process of radius to scaphoid Transverse carpal ligament: closes off carpal tunnel
Muscles and Tendons The extrinsic muslces and tendons of the hand fingers originate in the forearm. See the muscles listed for the forearm Muscles of the thumb – Extensor pollicus longus – Extensor pollicus brevis – Abductor pollicus longus – Flexor pollicus brevis
- Slides: 17