Wrist, Hand and Forearm

Question 1

How many bones are in the wrist and hand?

Answer 1

27 bones in total:

Phalanges: 14

Metacarpals: 5

Carpals: 8

Question 2

Name the carpal bones in the proximal row.

Answer 2

Scaphoid

Lunate

Triquetral

Pisiform

Question 3

Name the carpal bones in the distal row.

Answer 3

Trapezium

Trapezoid

Capitate

Hamate

Question 4

What is the clinical significance of the scaphoid bone?

Answer 4

Commonly fractured.

Prone to avascular necrosis due to poor blood supply.

Question 5

Describe the radiocarpal (wrist) joint.

Answer 5

Type: Synovial ellipsoid.

Movements: Flexion/extension, radial/ulnar deviation.

Close-pack position: Full extension with radial deviation

Question 6

Describe the midcarpal joint.

Answer 6

Type: Synovial complex saddle joint.

Articulation: Between proximal and distal carpal rows.

Movements: Flexion/extension, abduction/adduction.

Question 7

What are the movements at the wrist and their ranges?

Answer 7

Flexion: 85°

Extension: 85°

Radial Deviation: 15°

Ulnar Deviation: 45°

Question 8

What is the first carpometacarpal (CMC) joint, and why is it important?

Answer 8

Type: Synovial saddle joint.

Articulation: Between trapezium and base of first metacarpal.

Movements: Flexion/extension, abduction/adduction, opposition.

Important for thumb mobility.

Question 9

What contributes to wrist stability?

Answer 9

Multiple ligaments (e.g., palmar and dorsal radiocarpal, ulnocarpal).

Extensor and flexor retinacula.

Close-pack position: Extension with radial deviation.

Pronator quadratus.

Question 10

Describe the metacarpophalangeal (MCP) joints.

Answer 10

Type: Synovial ellipsoid joints.

Movements: Flexion/extension, abduction/adduction.

Ligaments: Palmar, collateral, transverse metacarpal.

Question 11

Describe the interphalangeal (IP) joints.

Answer 11

Type: Synovial hinge joints.

Movements: Flexion and extension.

Ligaments: Palmar and collateral.

Question 12

What are the active movements of the thumb?

Answer 12

Flexion/Extension

Abduction/Adduction

Opposition (combination of flexion, abduction, and medial rotation).

Question 13

Which muscles are involved in thumb opposition?

Answer 13

Flexor Pollicis Brevis (FPB)

Opponens Pollicis (OP)

Flexor Pollicis Longus (FPL)

Adductor Pollicis (AddP)

Abductor Pollicis Longus (APL)

Question 14

Describe the palmar radiocarpal ligament.

Answer 14

Connects the radius to the proximal carpal bones.

Provides stability to the wrist during flexion and extension.

Question 15

What is the clinical relevance of the TFCC (Triangular Fibrocartilaginous Complex)?

Answer 15

Provides stability to the distal radioulnar joint.

Often injured in wrist trauma.

Question 16

What are the muscles in the superficial group of the anterior compartment of the forearm?

Answer 16

Pronator Teres

Flexor Carpi Radialis (FCR)

Palmaris Longus

Flexor Carpi Ulnaris (FCU)

Flexor Digitorum Superficialis (intermediate layer)

Question 17

What are the muscles in the deep group of the anterior compartment of the forearm?

Answer 17

Flexor Digitorum Profundus (FDP)

Flexor Pollicis Longus (FPL)

Pronator Quadratus

Question 18

What is the nerve supply of the anterior compartment muscles?

Answer 18

Median nerve: Supplies most anterior muscles.

Ulnar nerve: Supplies Flexor Carpi Ulnaris (FCU) and the medial half of Flexor Digitorum Profundus (FDP).

Question 19

Describe the Pronator Teres muscle.

Answer 19

Origin: Medial epicondyle of humerus and coronoid process of ulna.

Insertion: Lateral surface of the mid-shaft of the radius.

Nerve supply: Median nerve (C6-C7).

Action: Pronation of the forearm.

Question 20

Name the muscles in the superficial group of the posterior compartment of the forearm.

Answer 20

Brachioradialis

Extensor Carpi Radialis Longus (ECRL)

Extensor Carpi Radialis Brevis (ECRB)

Extensor Digitorum

Extensor Digiti Minimi (EDM)

Extensor Carpi Ulnaris (ECU)

Question 21

Name the muscles in the deep group of the posterior compartment of the forearm.

Answer 21

Supinator

Abductor Pollicis Longus (APL)

Extensor Pollicis Longus (EPL)

Extensor Pollicis Brevis (EPB)

Extensor Indicis (EI)

Question 22

What is the nerve supply of the posterior compartment muscles?

Answer 22

Radial nerve: Supplies Brachioradialis and Extensor Carpi Radialis Longus (ECRL).

Posterior Interosseous Nerve (branch of Radial): Supplies other posterior compartment muscles.

Question 23

Describe the Extensor Digitorum (ED) muscle.

Answer 23

Origin: Lateral epicondyle of humerus.

Insertion: Bases of middle and distal phalanges of fingers via dorsal digital expansion.

Nerve supply: Posterior Interosseous Nerve (C7-C8).

Action: Extension of MCP and IP joints of fingers.

Question 24

What muscles are responsible for wrist flexion?

Answer 24

Flexor Carpi Radialis (FCR)

Flexor Carpi Ulnaris (FCU)

Palmaris Longus

Question 25

What muscles are responsible for wrist extension?

Answer 25

Extensor Carpi Radialis Longus (ECRL) Extensor Carpi Radialis Brevis (ECRB) Extensor Carpi Ulnaris (ECU)

Question 26

What muscles produce radial deviation (abduction) of the wrist?

Answer 26

Flexor Carpi Radialis (FCR) Extensor Carpi Radialis Longus (ECRL) Extensor Carpi Radialis Brevis (ECRB) Abductor Pollicis Longus (APL)

Question 27

What muscles produce ulnar deviation (adduction) of the wrist?

Answer 27

Flexor Carpi Ulnaris (FCU) Extensor Carpi Ulnaris (ECU)

Question 28

Describe the Flexor Digitorum Profundus (FDP) muscle.

Answer 28

Origin: Medial surface of ulna and anterior interosseous membrane. Insertion: Palmar surface of distal phalanges of fingers. Nerve supply: Lateral half: Median nerve (C8-T1). Medial half: Ulnar nerve (C8-T1). Action: Flexion of DIP, PIP, MCP, and wrist joints.

Question 29

What are the borders and contents of the carpal tunnel?

Answer 29

Borders: Roof: Flexor retinaculum. Floor: Carpal bones. Contents: Median nerve. Tendons of FDS, FDP, and FPL. Synovial sheaths.

Question 30

Describe the Abductor Pollicis Longus (APL) muscle.

Answer 30

Origin: Posterior surface of ulna, radius, and interosseous membrane. Insertion: Base of the first metacarpal. Nerve supply: Posterior Interosseous Nerve (C7-C8). Action: Abduction and extension of the thumb at CMC joint.