Acromioclavicular joint configuration
There is much variation in acromioclavicular joint configuration, which may be confused with pathology. The relationship of the acromion to the distal clavicle at the AC joint can be described in the coronal plane as 1-3:
- horizontal: normal
- low-lying: associated with shoulder impingement (unfortunately, there are no criteria for distinguishing a low-lying acromion from a high-riding clavicle) 2
- inferolateral: associated with shoulder impingement
Related Radiopaedia articles
Anatomy: Upper limb
-
skeleton of the upper limb
- clavicle
- scapula
- humerus
- radius
- ulna
- carpal bones (mnemonic)
- metacarpals
- phalanges
- accessory ossicles of the upper limb
- accessory ossicles of the shoulder
- accessory ossicles of the elbow
-
accessory ossicles of the wrist (mnemonic)
- os centrale carpi
- os epilunate
- os styloideum
- os hamuli proprium
- lunula
- os triangulare
- trapezium secondarium
- os paratrapezium
- os radiostyloideum (persistent radial styloid)
- joints of the upper limb
-
shoulder joint
- articulations
- sternoclavicular joint
- acromioclavicular joint
- glenohumeral joint
- scapulocostal joint (scapulothoracic joint)
- suprahumeral joint
- variants
- associated structures
-
movements
- scapular retraction (adduction)
- scapular protraction (abduction)
- scapular elevation
- scapular depression
- arm abduction
- arm adduction
- arm flexion
- arm extension
- arm internal rotation (medial)
- arm external rotation (lateral)
- blood supply - scapular anastomosis
- ossification centers
- articulations
-
elbow joint
- proximal radioulnar joint
- ligaments
- associated structures
- alignment
- blood supply - elbow anastomosis
- development
-
wrist joint
- articulations
-
ligaments
- intrinsic ligaments
- extrinsic ligaments
- associated structures
- extensor retinaculum
- flexor retinaculum
- joint capsule
- alignment
- ossification
-
hand joints
- movements
- articulations
- carpometacarpal joint
-
metacarpophalangeal joint
- palmar ligament (plate)
- collateral ligament
-
interphalangeal joint
- palmar ligament (plate)
- collateral ligament
-
shoulder joint
- spaces of the upper limb
- muscles of the upper limb
- shoulder girdle
- anterior compartment of the arm
- posterior compartment of the arm
- anterior compartment of the forearm
- posterior compartment of the forearm (extensors)
-
hand (mnemonic)
- thenar muscles
-
hypothenar muscles
- abductor digiti minimi
- flexor digiti minimi brevis
- opponens digiti minimi
- palmaris brevis (technically not a hypothenar muscle)
- intermediate muscles
- accessory muscles
- blood supply to the upper limb
-
arteries
- subclavian artery (mnemonic)
- axillary artery
- brachial artery (proximal portion)
- ulnar artery
- radial artery
- veins
-
arteries
- innervation of the upper limb
- intercostobrachial nerve
-
brachial plexus (mnemonic)
- branches from the roots
- branches from the trunks
- branches from the cords
- lateral cord
- posterior cord
- medial cord
- terminal branches
- lymphatic drainage of the upper limb