Anatomy of the Wrist Joint Flashcards

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Questions and Answers

What is the styloid process associated with the bony landmarks of the radius?

Styloid process (correct)

Head

Distal row

Proximal row

What are the bony landmarks of the ulna?

Proximal row

Styloid process (correct)

Distal row

Head (correct)

What comprises the bony landmarks of carpal bones?

Proximal row: Scaphoid, Lunate, Triquetrum, Pisiform; Distal row: Trapezium, Trapezoid, Capitate, Hamate

What is the radiocarpal joint composed of?

The distal end of the radius, the radioulnar disk proximally, and the scaphoid, lunate, and triquetrum distally Signup and view all the answers

What classification does the radiocarpal joint belong to?

Condyloid joint Signup and view all the answers

Define circumduction.

Using all four motions: flexion and extension, plus radial and ulnar deviation. Signup and view all the answers

What are midcarpal joints?

They occur between the two rows of carpal bones and are classified as plane joints. Signup and view all the answers

What do carpometacarpal (CMC) joints connect?

They occur between the distal row of carpal bones and the proximal end of the metacarpal bones. Signup and view all the answers

What is meant by wrist flexion and palmar flexion?

They are synonymous terms. Signup and view all the answers

What does hyperextension refer to?

Movement beyond the neutral position. Signup and view all the answers

How many degrees of flexion and extension are approximately present in the wrist?

90 degrees of flexion and 70 degrees of extension. Signup and view all the answers

What do radial and ulnar deviation occur around?

They occur in the frontal plane around the sagittal axis. Signup and view all the answers

What is the function of the dorsal radiocarpal ligament?

It limits the amount of flexion allowed at the wrist. Signup and view all the answers

Where does the radial collateral ligament attach?

It attaches to the styloid process of the radius and to the scaphoid and trapezium bones. Signup and view all the answers

What is the function of the ulnar collateral ligament?

It provides medial support to the wrist joint. Signup and view all the answers

What does the palmar radiocarpal ligament limit?

It limits wrist extension. Signup and view all the answers

What is the joint capsule?

It encloses the radiocarpal joint and is reinforced by ligaments. Signup and view all the answers

What is the role of the articular disk?

Acts as a shock absorber and fills the space between the distal ulna and adjacent carpal bones. Signup and view all the answers

What is palmar fascia also known as?

Palmar aponeurosis. Signup and view all the answers

Where is the flexor carpi ulnaris muscle located?

Along the ulnar, slightly anterior side of the forearm. Signup and view all the answers

What does the flexor carpi radialis muscle do?

It is a prime mover in wrist flexion and radial deviation. Signup and view all the answers

Describe the palmaris longus muscle.

A superficial muscle running to attach in the midline of the palmar fascia. Signup and view all the answers

Where is the extensor carpi radialis longus muscle located?

On the posterior side of the wrist. Signup and view all the answers

What does the extensor carpi radialis brevis muscle arise from?

The common extensor tendon on the lateral epicondyle. Signup and view all the answers

Study Notes

Anatomy of the Wrist Joint

Boney Landmarks: Radius
- Key structure includes the styloid process.
Boney Landmarks: Ulna
- Notable features are the styloid process and the head.
Boney Landmarks: Carpal Bones
- Proximal row consists of: Scaphoid, Lunate, Triquetrum, Pisiform.
- Distal row consists of: Trapezium, Trapezoid, Capitate, Hamate.
Radiocarpal Joint
- Formed by the distal end of the radius and the radioulnar disk superiorly, articulating with scaphoid, lunate, and triquetrum inferiorly.
Classification of Radiocarpal Joint
- Condyloid joint: The concave distal radius and articular disk articulate with convex scaphoid, lunate, and triquetrum.
Circumduction
- Movement involves all four motions: flexion, extension, radial deviation, and ulnar deviation.
Midcarpal and Intercarpal Joints
- Located between rows of carpal bones, they allow wrist motion. Classified as plane joints due to their irregular shape.
Carpometacarpal (CMC) Joints
- Formed between the distal row of carpal bones and the proximal metacarpals.
Joint Motions
- Wrist flexion and palmar flexion are equivalent; similarly, extension, hyperextension, and dorsiflexion are synonyms.
- Neutral position is midway between flexion and extension, aligning the hand with the forearm.
Hyperextension
- Defined as movement that exceeds the neutral position.
Flexion and Extension Degrees
- Approximately 90 degrees of flexion and 70 degrees of extension is possible.
Radial and Ulnar Deviation
- Occurs in the frontal plane around the sagittal axis; radial deviation roughly 25 degrees and ulnar deviation about 35 degrees.
Dorsal Radiocarpal Ligament
- Attaches from the distal radius to the posterior surfaces of scaphoid, lunate, and triquetrum. Limits wrist flexion.
Radial Collateral Ligament
- Connects the styloid process of the radius with the scaphoid and trapezium.
Ulnar Collateral Ligament
- Extends from the styloid process of the ulna to the pisiform and triquetrum, providing medial support.
Palmar Radiocarpal Ligament
- A robust ligament limiting wrist extension, linking the anterior surfaces of the distal radius and ulna to the proximal flexion.
Joint Capsule
- Encloses the radiocarpal joint, reinforced by collateral ligaments and palmar/dorsal radiocarpal ligaments.
Articular Disk
- Positioned on the distal ulna, articulates with triquetrum and lunate. Functions as a shock absorber and filler between bones.
Palmar Fascia
- A thick, triangular fascia in the palm, also called palmar aponeurosis; covers flexor tendons and protects palm structures.
Flexor Carpi Ulnaris Muscle
- A superficial muscle situated along the ulnar side of the forearm.
Flexor Carpi Radialis Muscle
- Superficial, runs from the medial epicondyle to the second and third metacarpals; a prime mover for wrist flexion and radial deviation.
Palmaris Longus Muscle
- Superficial muscle that runs from the medial epicondyle to the palmar fascia, particularly active during wrist flexion.
Extensor Carpi Radialis Longus Muscle
- Located at the wrist's posterior side, primarily superficial in position.
Extensor Carpi Radialis Brevis Muscle
- Positioned alongside the extensor carpi radialis longus, arises from the common extensor tendon at the lateral epicondyle.

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Description

Explore the essential bony landmarks and features of the wrist joint with this informative flashcard quiz. Learn about the radius, ulna, and carpal bones, including the important radiocarpal joint. Perfect for anatomy students looking to reinforce their understanding of wrist anatomy.