Pronation, Supination and Carpal Tunnel Flashcards
What is pronation of the forearm?
Pronation is the inward rotation of the forearm, causing the palm to face downward or posteriorly.
What is supination of the forearm?
Supination is the outward rotation of the forearm, causing the palm to face upward or anteriorly.
Which two joints are responsible for pronation and supination?
The proximal and distal radioulnar joints are responsible for pronation and supination.
What bones participate in forearm pronation and supination?
The radius and ulna are the bones involved in forearm pronation and supination.
What are the primary muscles responsible for pronation?
The primary muscles responsible for pronation are the pronator teres and pronator quadratus.
What are the primary muscles responsible for supination?
The primary muscles responsible for supination are the supinator and biceps brachii.
Which nerve innervates the pronator teres?
The median nerve innervates the pronator teres.
Which nerve innervates the pronator quadratus?
The anterior interosseous branch of the median nerve innervates the pronator quadratus.
Which nerve innervates the supinator muscle?
The deep branch of the radial nerve innervates the supinator muscle.
What is the role of the biceps brachii in supination?
The biceps brachii assists in supination, especially when the forearm is flexed.
How does the radius move during pronation?
During pronation, the radius crosses over the ulna.
How does the radius move during supination?
During supination, the radius and ulna are parallel.
What is the anatomical position of the forearm in full supination?
In full supination, the palm faces anteriorly in the anatomical position.
What is the functional significance of pronation and supination in daily activities?
Pronation and supination allow for functional hand positioning in activities like writing and tool use.
What structure holds the distal radius and ulna together during pronation and supination?
The triangular fibrocartilage complex (TFCC) stabilizes the distal radius and ulna during pronation and supination.
What type of joint is the proximal radioulnar joint?
The proximal radioulnar joint is a pivot joint.
What type of joint is the distal radioulnar joint?
The distal radioulnar joint is a pivot joint.
What ligaments stabilize the proximal radioulnar joint?
The annular ligament stabilizes the proximal radioulnar joint.
What ligaments stabilize the distal radioulnar joint?
The articular disc (TFCC) stabilizes the distal radioulnar joint.
What is the carpal tunnel?
The carpal tunnel is a narrow passage in the wrist formed by the carpal bones and the flexor retinaculum.
What structures pass through the carpal tunnel?
The carpal tunnel contains the median nerve, flexor digitorum superficialis tendons, flexor digitorum profundus tendons, and flexor pollicis longus tendon.
What is the function of the flexor retinaculum?
The flexor retinaculum forms the roof of the carpal tunnel and holds the flexor tendons in place.
What is the primary nerve affected in carpal tunnel syndrome?
The median nerve is the primary nerve affected in carpal tunnel syndrome.
What are the symptoms of carpal tunnel syndrome?
Symptoms of carpal tunnel syndrome include numbness, tingling, and weakness in the lateral three and a half fingers.
What factors can contribute to carpal tunnel syndrome?
Repetitive wrist movements, pregnancy, diabetes, and arthritis can contribute to carpal tunnel syndrome.
What is the role of the lumbrical muscles in relation to the carpal tunnel?
The lumbricals do not pass through the carpal tunnel but are important in fine motor control of the fingers.
What clinical tests are used to diagnose carpal tunnel syndrome?
Phalen’s test and Tinel’s sign are used to diagnose carpal tunnel syndrome.
What is the function of the synovial sheaths within the carpal tunnel?
Synovial sheaths reduce friction for tendons passing through the carpal tunnel.
What are the treatment options for carpal tunnel syndrome?
Treatment options for carpal tunnel syndrome include wrist splints, corticosteroid injections, and surgical release of the flexor retinaculum.
How can pronation and supination be affected by nerve injuries?
Median nerve injuries can impair pronation, while radial nerve injuries can weaken supination.
