Advanced Acromioclavicular Joint Quiz

Q1. A direct fall onto the lateral shoulder most commonly produces which type of injury at the acromioclavicular joint?

• Radial head subluxation
• Posterior elbow dislocation
• Distal radioulnar joint dislocation
• Acromioclavicular joint separation

Q2. Complete disruption of both the acromioclavicular and coracoclavicular ligaments most directly causes what mechanical consequence?

• Locking of the humeral head within the glenoid cavity
• Fusion of the clavicle to the acromion
• Marked separation between the clavicle and scapula
• Dislocation of the radial head

Q3. Why can the distal clavicle appear elevated in a severe acromioclavicular separation?

• The scapula and upper limb descend relative to the supported clavicle
• The clavicle actively contracts upward
• The humerus pushes the clavicle through the trapezius
• The coracoid process rotates above the clavicle

Q4. Which component of the coracoclavicular ligament is particularly important in resisting superior displacement of the clavicle relative to the scapula?

• Coracoacromial ligament
• Superior transverse scapular ligament
• Conoid ligament
• Transverse humeral ligament

Q5. Which component of the coracoclavicular ligament is oriented more horizontally and helps resist compression and displacement of the scapula relative to the clavicle?

• Costoclavicular ligament
• Conoid ligament
• Coracoacromial ligament
• Trapezoid ligament

Q6. What is the principal functional importance of small rotational movements at the acromioclavicular joint?

• They rotate the radius around the ulna
• They permit adaptive positioning of the scapula during shoulder girdle movement
• They prevent all motion between the scapula and thorax
• They directly produce elbow flexion

Q7. Why is the coracoclavicular ligament considered functionally important even though it does not directly cross the acromioclavicular joint cavity?

• It forms the articular cartilage of the joint
• It strongly anchors the scapula to the clavicle and indirectly stabilizes the joint
• It forms the roof of the carpal tunnel
• It connects the humeral head directly to the clavicle

Q8. Degenerative changes of the acromioclavicular joint can produce pain particularly during which shoulder movement pattern?

• Horizontal adduction across the chest
• Pronation of the forearm
• Extension of the wrist
• Flexion of the fingers

Q9. Which finding would most strongly suggest major coracoclavicular ligament disruption rather than an isolated mild acromioclavicular ligament sprain?

• Reduced movement at the distal radioulnar joint
• Isolated tenderness over the radial head
• Normal alignment between the clavicle and scapula
• Marked increase in the coracoclavicular distance

Q10. Which description best summarizes the functional anatomy of the acromioclavicular joint?

• A plane synovial joint that combines small movements with ligamentous stability to permit coordinated scapular motion
• A ball-and-socket joint responsible for most humeral rotation
• A hinge joint responsible for flexion and extension of the upper limb
• A rigid fibrous joint that normally permits no scapular movement