Lecture 4: The forearm and wrist Flashcards
Where is the forearm?
The forearm houses the muscles which flex and extend the wrist, fingers and thumb. ‘Long’ tendons travel to the fingers and thumb > injury to the nerves which innervate the forearm muscles impair hand function
Where is the forearm?
The forearm houses the muscles which flex and extend the wrist, fingers and thumb. ‘Long’ tendons travel to the fingers and thumb > injury to the nerves which innervate the forearm muscles impair hand function
What is commonly fractured?
The distal radius
Is the ulna involved in the wrist?
No
What is the articulation in the wrist?
Articulation between the distal radius, scaphoid, and lunate
What type of joint is the Condyloid synovial joint?
Condyloid synovial joint (modified ball and socket)
Which ligaments strengthens the Condyloid synovial joint anteriorly and posteriorly?
Radiocarpal ligaments
Which side is the radius of the forearm?
Thumb side
What side is the Ulna of the forearm?
The medial side
What does the Ulna and radius bones articulate with?
Humerus at the elbow
How many bones does the radius articulate with at the wrist joint?
The radius articulates with 2 carpal bones at the radiocarpal (wrist) joint
Where does the ulna and radius articulate with each other?
Articulate with each other at the proximal and distal radioulnar joints (=pronation and supination
What connects the Ulna and the radius?
A strong interosseous membrane connects them. The IOM has holes in it for the passage of vessels
What can the wrist be referred to as?
Carpus
What does the carpus consist of?
= 8 small bones, arranged in 2 rows, that lie distal to the radius and ulna
What are the bones of the Hand?
Distal phalanges
Intermediate phalanges
Proximal phalanges
Metacarpals
Carpals
What are the joints of the hand?
Joints:
Distal interphalangeal (DIPJ)
Proximal interphalangeal (PIPJ)
Interphalangeal joint (IPJ) of the thumb
Metacarpophalangeal (MCPJ)
Carpometacarpal (CMCJ)
What muscles move the wrist?
Muscles in the forearm that cross the wrist = move the wrist
What else does the muscles in the forearm move?
The forearm also contains muscles that move the elbow, proximal radioulnar joint, thumb, and fingers
Where are the two muscle compartments in the forearm?
Anterior and Posterior
What do the muscles anteriorly in the forearm do?
Muscles in the anterior compartment flex (bend) the wrist (and digits)
What do the muscles posteriorly in the forearm do?
Muscles in the posterior compartment extend (straighten) the wrist (and digits)
What are the movements in the wrist?
Flexion and extension
Abduction and adduction
What are the movements in the wrist?
Flexion and extension
Abduction and adduction