Wrist Anatomy and Function Quiz
24 Questions
2 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following bones is not part of the distal carpal row?

  • Scaphoid (correct)
  • Capitate
  • Trapezium
  • Hamate
  • The triangular fibrocartilage complex (TFCC) helps stabilize the radial side of the wrist.

    False

    What type of joint is the intercarpal joint?

    Synovial gliding

    The wrist joint complex consists of multiple articulations involving the eight carpal bones, metacarpals, and the distal ______.

    <p>radius</p> Signup and view all the answers

    Match the following carpal bones with their respective characteristics:

    <p>Pisiform = Sesamoid bone enhancing flexor carpi ulnaris Lunate = Articulates with the distal radius Capitate = Largest carpal bone Trapezium = Articulates with the first metacarpal</p> Signup and view all the answers

    What is the function of the triangular fibrocartilage complex (TFCC)?

    <p>Acts as a load-bearing structure on ulnar side</p> Signup and view all the answers

    The wrist has three main joints, including the distal radioulnar joint.

    <p>True</p> Signup and view all the answers

    Which axis of motion allows for 35 degrees of ulnar deviation?

    <p>Radial-ulnar axis</p> Signup and view all the answers

    What type of joint is the wrist classified as?

    <p>Synovial Ellipsoid joint</p> Signup and view all the answers

    During wrist ulnar deviation, the scaphoid and lunate roll toward the radius.

    <p>False</p> Signup and view all the answers

    What are the two main types of ligaments in the wrist?

    <p>Extrinsic and Intrinsic ligaments</p> Signup and view all the answers

    The scaphoid transmits _____% of force during wrist extension.

    <p>51</p> Signup and view all the answers

    Which ligament plays an important role in stabilizing the wrist when lifting heavy objects?

    <p>Scapholunate ligament</p> Signup and view all the answers

    Match the following wrist ligaments with their functions:

    <p>Radial collateral ligament = Provides stability to the lateral aspect of the wrist Volar radiocarpal ligaments = Supports the palm side of the wrist Dorsal radiocarpal ligaments = Supports the back of the wrist Scapholunate ligament = Facilitates movement &amp; provides stability</p> Signup and view all the answers

    Radial deviators are stronger than ulnar deviators.

    <p>True</p> Signup and view all the answers

    During wrist extension, the scaphoid/lunate roll _____ and glide _____ .

    <p>posteriorly (toward dorsum), anteriorly (toward palm)</p> Signup and view all the answers

    What two movements are involved in wrist circumduction?

    <p>Flexion and Adduction</p> Signup and view all the answers

    Carpal tunnel syndrome is more prevalent in males than females.

    <p>False</p> Signup and view all the answers

    What is the Finkelstein test used to identify?

    <p>De Quervain Tenosynovitis</p> Signup and view all the answers

    In wrist arthrokinematics, the roll occurs in the same direction, while the glide occurs in the ______ direction.

    <p>opposite</p> Signup and view all the answers

    Match the wrist injuries with their descriptions:

    <p>Ligamentous sprain = Injury to ligaments in the wrist De Quervain Tenosynovitis = Pain due to thickened tendon sheaths Carpal tunnel syndrome = Entrapment neuropathy affecting the wrist Fracture of the distal radius = Breakage in the radius near the wrist</p> Signup and view all the answers

    Which ligament is often associated with ligamentous sprains in the wrist?

    <p>Scapholunate ligament</p> Signup and view all the answers

    The wrist has 3 degrees of freedom in its movements.

    <p>False</p> Signup and view all the answers

    What is the loose packed position of the wrist?

    <p>Neutral wrist with a slight degree of adduction (ulnar deviation)</p> Signup and view all the answers

    Study Notes

    Biomechanics 2 Course Information

    • Course title: Biomechanics 2
    • Lecturer: Dr. Amany Gomaa Atiaa
    • Affiliation: Lecturer of Burn & Surgery, Faculty of Physical Therapy, Sinai University
    • Website: sinaiuniversity.net

    Biomechanics of the Wrist Joint

    • Components: Wrist complex, ligaments, muscles
    • Positions: Loose packed position, close packed position
    • Other features: Angles, arthrokinematics

    Wrist Complex and Articulations

    • Structure: Multiple articulations of eight carpal bones, distal radius, ulnocarpal space structures, metacarpals, and each other.

    Bony Structure

    • Division: The carpus is divided into proximal and distal rows.
    • Distal row: Trapezium, trapezoid, capitate, and hamate (relatively immobile)
    • Distal function: Forms carpometacarpal joint.
    • Proximal row: Scaphoid, lunate, and triquetrum (more mobile)
    • Proximal function: Forms radiocarpal joint with the distal radius.

    Wrist Joint Components

    • Distal radioulnar joint: synovial pivot
    • Radiocarpal joint: condyloid synovial
    • Midcarpal joint: synovial gliding
    • Additional parts: ulnocarpal, carpometacarpal (saddle joint), and intercarpal joints

    Triangular Fibrocartilage Complex (TFCC)

    • Function: Load-bearing structure between the lunate, triquetrum, and ulnar head, stabilizes the ulnar aspect of the wrist.
    • Injury risk: Acute or chronic degenerative injury.
    • Diagnosis: Gold standard is arthroscopy, sometimes MRI reveals abnormalities.

    Radius and Ulna

    • Radius angle: Distal end angles 25 degrees toward the ulnar (medial) direction, allowing greater ulnar deviation than radial deviation.
    • Radius angle limitation: Bony impingement of carpal (wrist) side against the styloid process of the radius limits radial deviation.
    • Ulna angle: Distal articular surface angles 10 degrees in the palmar direction. This tilt influences wrist flexion.

    Angles

    • Sagittal plane: 10 degrees, range of flexion
    • Frontal plane: 25 degrees, range of ulnar deviation.

    Radiocarpal Joint

    • Proximal component: Biconcave distal end of the radius and articular disc
    • Distal component: Biconvex proximal row of carpal (scaphoid, lunate, triquetrum).
    • Radiocarpal role of triquetrum: At full ulnar deviation, the medial surface of the triquetrum contacts the articular disc.
    • Joint type: Convex on concave; important for mobilization.
    • Force distribution: 20% of compression passes through the articular disc, 80% passes through the scaphoid and lunate to the radius.
    • Largest contact region: When the wrist is slightly extended (10° ) and slightly deviated in the ulnar direction.

    Wrist Joint Positions

    • Close packed position: Extension with slight abduction/radial deviation.
    • Loose packed position: Neutral wrist with slight abduction/ulnar deviation.

    Wrist Ligaments

    • Extrinsic ligaments: Attach carpal bones to the radius/metacarpals. Includes volar and dorsal ligaments; palmar radiocarpal, dorsal radiocarpal, radial collateral, ulnar collateral.
    • Three important dorsal extrinsic ligaments: dorsal intercarpal, dorsal radiotriquetral, and dorsal radioulnar.
    • Intrinsic ligaments: Originate and insert on carpal bones, including scapholunate interosseous, lunotriquetral interosseous, and scaphotrapeziotrapezoid.

    Wrist Muscles

    • Primary set: Act on the wrist only, tendons attach distally.
    • Secondary set: Tendons cross the carpus to attach to the digits (act on the wrist and hand).
    • Extensor muscles (primary/secondary): E.g., extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris, extensor digitorum, extensor indicis, extensor digiti minimi, extensor pollicis longus.
    • Flexor muscles (primary/secondary): Includes flexor carpi radialis, flexor carpi ulnaris, palmaris longus, flexor digitorum profundus, flexor digitorum superficialis, flexor pollicis longus, abductor pollicis longus, extensor pollicis brevis

    Wrist Movements

    • Flexion: Anterior movement of the wrist or hand
    • Extension: Posterior movement of the wrist or hand
    • Radial deviation: Abduction of the hand
    • Ulnar deviation: Adduction of the hand

    Wrist Kinematics and Kinetics

    • Osteokinematics: Wrist has two degrees of freedom (flexion/extension and ulnar/radial deviation)
    • Circumduction: Combination of the aforementioned movements.
    • Axis of rotation: Passes through the head of the capitate.
    • Kinetics of Force Transmission: In extension, scaphoid transmits 51% of force, lunate transmits 49%. In neutral, it is 53% and 47%, and in flexion 55% and 45% respectively.

    Wrist and Hand Injuries

    • Ligamentous sprain: Scapholunate ligament injury, TFCC injury
    • Fracture of distal radius
    • Fractures of scaphoid and lunate.
    • De Quervain's tenosynovitis (thickening of tendon sheaths/pain)
    • Carpal tunnel syndrome (median nerve compression)

    Contacting the Lecturer

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Description

    Test your knowledge on the anatomy and function of the wrist joint complex with this engaging quiz. Explore questions on carpal bones, ligaments, and the mechanics of wrist movement. Perfect for students studying anatomy or physical therapy.

    More Like This

    Anatomy of the Wrist
    11 questions
    Bones and Joints of the Wrist and Hand
    45 questions
    Wrist Complex Anatomy and Function
    45 questions
    Wrist Anatomy and Ossification Quiz
    22 questions
    Use Quizgecko on...
    Browser
    Browser