AP shoulder (highly consider comparison view)
AC<unk> 
Normal width of AC<unk>  in adults is 1-3mm
By age 60 width is often less than 1mm
Children and adolescents have a slightly wider<unk>  space
CC<unk> 
Normal distance is 11-13mm
Comparison to opposite CC<unk>  space is more important
Increase in CC distance of 25-50% indicates complete CC ligament disruption
Zanca view  (AP with 10-15 degree cephalic tilt)
Consider if AP view is ambiguous, concern for type II injury or distal clavicle injury
Axillary view
Obtain if coracoid tenderness is present to rule-out associated coracoid fracture
Helps to confirm ant-post position of clavicle in injury types III-IV
AC<unk> 
Normal width of AC<unk>  in adults is 1-3mm
By age 60 width is often less than 1mm
Children and adolescents have a slightly wider<unk>  space
CC<unk> 
Normal distance is 11-13mm
Comparison to opposite CC<unk>  space is more important
Increase in CC distance of 25-50% indicates complete CC ligament disruption
Zanca view  (AP with 10-15 degree cephalic tilt)
Consider if AP view is ambiguous, concern for type II injury or distal clavicle injury
Axillary view
Obtain if coracoid tenderness is present to rule-out associated coracoid fracture
Helps to confirm ant-post position of clavicle in injury types III-IV
Normal width of AC<unk>  in adults is 1-3mm
By age 60 width is often less than 1mm
Children and adolescents have a slightly wider<unk>  space
Normal distance is 11-13mm
Comparison to opposite CC<unk>  space is more important
Increase in CC distance of 25-50% indicates complete CC ligament disruption
Increase in CC distance of 25-50% indicates complete CC ligament disruption
Consider if AP view is ambiguous, concern for type II injury or distal clavicle injury
Obtain if coracoid tenderness is present to rule-out associated coracoid fracture
Helps to confirm ant-post position of clavicle in injury types III-IV
AC ligament sprain
AC<unk>  intact
Mild swelling, no deformity
CC ligaments are nontender
Only distal-most 1-2cm of clavicle is tender
Active overhead and cross-body ROM are limited by pain
Often no abnormality is seen on xray
Slight widening of the AC<unk>  may occur

AC ligament torn
Coracoclavicular (CC) ligament may be partially torn but is intact
Prominent and tender AC<unk>  with significant swelling
Minimal tenderness of CC ligaments reflecting lack of significant injury
May be instability of the distal clavicle in the horizontal plane
Partial elevation of the distal clavicle with no or minimal widening of CC distance

AC and CC ligaments torn
Complete dislocation of the<unk> 
Deformity of the AC<unk>  is clearly visible
Marked tenderness of CC ligaments (helps distinguish Type 3 from type 2)
Palpable posterior fullness or deformity despite significant swelling
Elevated distal clavicle and increased CC distance
Distal clavicle is positioned above the plane of the top of the acromion

Complete dislocation with posterior displacement of distal clavicle in/through trapezius
SC dislocation may be appreciated
Axillary view required to visualize the posterior dislocation

More severe form of type III injury
Superior dislocation of the<unk>  of 1-3x the normal spacing
CC ligament distance is increased 2-3x normal *Disruption of the deltotrapezial fascia
Shoulder appears to droop
Severe superior displacement of clavicle (may cause tenting, ischemia of skin)
Clavicle is perhced above the muscle and does not reduce when patient shrugs shoulder
Clavicle is elevated above acromion approximately 1-3x width of the clavicle
CC distance is increased 2-3x normal range

Complete dislocation with clavicle displaced inferiorly
Complete disruption of the AC and CC ligaments
Acromioclavicular joint injury
Traumatic/Acute:
Ankle syndesmosis injury
Shoulder Dislocation
Scapular fracture
Anterior shoulder dislocation
Lunotriquetral ligament instability
Posterior shoulder dislocation