Obsolete anterior shoulder dislocation refers to the first dislocation of glenohumeral joint for at least 3 weeks. Its incidence rate is extremely low. The long duration of dislocation results in the contracture of the muscle and joint capsule around glenoid tendon and the formation of fibrous tissue and scarring. It is often accompanied by the bone defect of the anteroinferior border of glenoid (bony Bankart injury) and the compression fracture of posterosuperior humeral head (Hill-Sachs injury) . The above pathological changes of obsolete anterior shoulder dislocation lead to poor conservative treatment effect, difficulty of closed reduction and high recurrence rate. Therefore, open reduction becomes the prior choice. However, the maintenance of reduction is extremely difficult after operation. The previously reported transarticular fixation will destroy articular surface and aggravate joint stiffness. The joint capsule contraction or Bankart repair surgery has a high rate of redislocation and will significantly affect rotation. Through transplanting the coracoid process fragment attached with conjoint tendon to anteroinferior scapular neck, Latarjet procedure increases the curvature of glenoid and forms a mechanical barrier, which can effectively avoid redislocation and has little effect on the mobility of shoulder joint. Numerous studies have confirmed that Latarjet surgery is superior to other procedures in the treatment of recurrent anterior shoulder dislocation. However, its application for the treatment of obsolete anterior shoulder dislocation is barely reported.Objective To evaluate the clinical efficacy of open reduction combined with Latarjet procedure in the treatment of obsolete anterior shoulder dislocation.

From January 2012 to January 2018, 14 patients (16 shoulders) with obsolete anterior shoulder dislocation were involved in this study. There were 8 males and 6 females. The age ranged from 30 to 70 years with an average of 51.2 years. The duration of dislocation was 8-22 weeks with an average of 10.2 weeks. Causes of injury: fall damage (10 cases) and traffic accidence (4 cases) . 12 cases were combined with Hill-Sachs injury, and the average proportion of humeral head defect was 32%. 11 cases were combined with bony Bankart injury, and the average proportion of glenoid defect was 13%. 9 cases were combined with rotator cuff injury, and 6 cases were combined with proximal humeral fracture. No neurovascular injury was found. The range of motion (anteflexion, abduction, internal rotation and external rotation) and functional score (VAS, ASES and UCLA) of shoulder joint were examined before operation. The deltopectoral approach was used to completely release the contracture of joint capsule and surrounding soft tissue. After the removal of the scar tissue in glenoid fossa, the glenohumeral joint was reduced. Then, the Latarjet procedure was performed to reconstruct glenoid radian to maintain the reduction. Meanwhile, concomitant complications such as Hill-Sachs injury, rotator cuff injury and proximal humeral fracture, etc. were treated as well based on the condition of injury.

All the 14 patients were followed up for 10 to 22 months with an average of 18 months. During the follow-up period, no redislocation of shoulder joint was found. One patient developed postoperative shoulder numbness and was considered to have axillary nerve injury, and the condition recovered 1 month later. There was no complication such as infection, iatrogenic fracture or other neurovascular injury. During the last follow up: the mean flexion angle increased from (65.9±10.4) °to (112.1±13.3) ° (P=0.000) ; the mean abduction angle increased from (41.1±9.7) °to (63.3±13.6) ° (P=0.000) ; the mean external rotation angle at adduction increased from (10.7±4.3) °to (22.1±5.1) ° (P=0.000) ; the mean adduction and internal rotation angle increased from (52.6±5.3) °to (54.0±6.0) ° (P=0.081) ; the VAS score decreased from (5.4±1.4) to (1.7±1.1) (P=0.000) ; the ASES score increased from (34.1±10.6) to (70.8±12.3) (P=0.000) ; the UCLA score increased from (10.1±3.2) to (22.6±4.6) (P=0.000) . Other than internal rotation, there were significant differences in the range of motion and the function of shoulder joint before and after operation.

For obsolete anterior shoulder dislocation, open reduction combined with Latarjet procedure can effectively reconstruct the anterior stability of shoulder joint. Meanwhile, the correct treatment of concomitant injury during operation and postoperative early rehabilitation exercise are also important factors to improve the surgical curative effect.

Open reduction; Latarjet; Obsolete; Shoulder joint; Anterior dislocation