[Treatment of acromio-clavicular dislocations using coracoacromial ligament plasty].

Purpose: Plasty transfer using the coracoacromial ligament (Cadenat) for the treatment of acromioclavicular separation is usually too weak and too short. The authors used a reinforcement flap, made by a lateral supraclavicular detachment of the superior fibrous-capsular sheath.

Material And Method: Twenty-six acromioclavicular separations were radiographically studied using an axillary view. Twenty-one patients had a posterior dislocation of the lateral end of the clavicle. A pouch formed by the superior detachment was present in all cases with posterior displacement. In 19 case out of 26, this detachment was used to create a quadrangular flap with acromial support. The end of the coracoacromial ligament was attached to this long flap which provided adequate reinforcement along its entire length.

Results: There was a statistical correlation (p = 0.05) between the posterior component of the separation and the presence of this detachment. In the 19 reinforced plasties, no recurrence of posterior dislocation was reported, a mild undercorrection and 2 overcorrections were noted. Recurrent posterior dislocation was reported in the 7 non-reinforced coracoacromial plasties, and superior dislocation was reported twice.

Discussion: Posterior acromioclavicular dislocation is present in 80 per cent of cases. Diagnosis mainly uses the axillary view. It is always associated with a lateral supraclavicular detachment providing a 3 to 5 cm long downward flap which is used as a natural reinforcement for the coracoacromial ligamentoplasty.