Ac Joint Disruption Radiopaedia

A acromioclavicular joint injury otherwise known as a shoulder separation is a traumatic injury to the acromioclavicular ac joint with disruption of the acromioclavicular ligaments and or coracoclavicular cc ligaments.

Ac joint disruption radiopaedia. Acromio clavicular dislocation type iii. Dislocation of the right acromioclavicular joint with the clavicle displaced superiorly. This well known 6 type system is a modification of the earlier 3 class classification system described by allman 1967 2 and tossy 1963. The acromioclavicular joint can be assessed with standard shoulder x rays.

The right acromioclavicular joint dislocation is incidentally noted suggesting an old injury. Gross anatomy the acromioclavicular joint is between the small facet of the convex distal clavicle and flat medial acromion. Inferior border of the clavicle is elevated beyond the superior border of the acromion. Loss of alignment of the inferior surfaces of the clavicle and acromion indicates disruption of the acromioclavicular ligaments at the acromioclavicular joint acj.

According to the rockwood classification it is considered a type iii injury. Widening of the coracoclavicular cc distance 23mm case discussion. Minor ligamentous disruption may not be detectable on a plain radiograph as alignment is not lost. The rockwood classification 1998 is the most common classification system in use for acromioclavicular joint injuries 3.

Children and adolescents have a slightly wider joint space. The cause of dyspnea in this case is a right pleural effusion. Ac joint normal width of ac joint in adults is 1 3mm. According to the rockwood classification it is considered a type iii injury.

Comparison to opposite cc joint space is more important increase in cc distance of 25 50 indicates complete cc ligament disruption. The cause of dyspnoea in this case is a right pleural effusion. By age 60 width is often less than 1mm. Acromioclavicular joint injuries are characterized by damage to the acromioclavicular joint and surrounding structures.

The acromioclavicular joint acj is a plane synovial joint diarthrodial joint of the pectoral girdle. Almost invariably traumatic in etiology they range in severity from a mild sprain to complete disruption. Cc joint normal distance is 11 13mm.