We perform a retrospective analysis of 62 patients from 2015 to 2018 with acromioclavicular trauma,
evaluated with conventional radiography,
CT and MRI.
A 64-slice CT scanner and 1.5 or 3 Tesla MRI equipments were used.
Acromioclavicular stability is maintained by the coracoclavicular ligaments (conoid and trapezoid) in addition to the AC capsule and ligaments.
On conventional radiography the use of a 10° to 15° cephalic angulation (Zanca view) is prefered to isolate the ACJ from other structures.
Axillary projections can be performed to evaluate for anterior or posterior displacement of the distal clavicle
CT its not performed in the routine evaluation of ACJ injuries.
In some cases may add additional information in a complex fracture injury.
MRI allow us a complete evaluation of the ligaments as well as muscle structures compromise.
The Rockwood classification (fig.
3) for ACJ injuries is widely used in clinical practice.
Six grades of injury are classified according to displacement of the distal clavicle,
involvement of the AC and coracoclavicular ligaments,
and the integrity of the deltoid and trapezius musculature.
Grade 1 (fig.
4)
Represent a partial sprain of the acromioclavicular ligament.
AC joint remains stable,
and the rest of the ligaments are intact. Radiographs are normal.
Difficult diferentiation in adults who commonly have pre-existing chronic findings that are indistinguishable from mild acute trauma.
Grade 2 (fig.
5)
Disruption of the ACJ capsule and AC ligaments. Coracoclavicular ligaments are intact or slightly sprain,
most commonly involving the conoid component.
Radiographs show a widened ACJ secondary to medial scapular rotation,
clavicle elevated but not above the superior border of the acromion,
and a normal or slightly increased coracoclavicular distance.
Grade 3 (fig 8)
Involve complete tears of the acromioclavicular and coracoclavicular ligaments.
Clavicle is elevated above the superior border of the acromion. Widening of the ACJ,
but coracoclavicular distance is less than twice normal. The deltoid and trapezius muscles can be torn at the distal end of the clavicle.
Grade 4
Grade 3 injuries with posterior displacement of the clavicle. The trapezius and deltoid muscles are torn from the clavicular insertions.
Anterior dislocations of the sternoclavicular joint can also occur.
Grade 5
Severe Grade 3 injury.
The lateral trapezius and deltoid insertions,
acromioclavicular and coracoclavicular ligaments are all torn.
Clavicle is markedly elevated and coracoclavicular distance is more than double normal (>25 mm).
Grade 6
Result from a inferiorly displaced of the clavicle behind the coracobrachialis and biceps tendon.
Fractures of the clavicle and ribs are associated ,
as well as brachial plexus injuries.
The importance of this classification lies on the therapeutic management.
Grade 1 and 2 injuries are treated nonoperatively.
Treatment of Grade 3 ACJ injury is controversial.
The orthopaedic literature is full of articles which sugest surgical treatment.
Other many published reports shown satisfactory results with non-operative treatment.
Grades 4-6 and open ACJ injuries are indications for surgical treatment but even these injuries can be treated non-operatively.