Glenohumeral instability can present as a spectrum of disability, ranging from subtle anterior shoulder pain with apprehension to frank recurrent dislocations. Perthes¹ and Bankart² described that a separated labrum and capsule were the anatomic abnormalities responsible for anterior shoulder instability and reported on surgical techniques involving the reattachment of the avulsed labrum and capsule to the glenoid rim. Rowe et al.³ reported on the long-term results of open Bankart repair. They noted 97% excellent or good results, with a 3.5% dislocation rate, but 31% of the patients had some degree of motion loss and only 33% of those patients involved in overhand athletics were able to return to their previous activity level. Other surgeons^{4,5,6,7,8,9,10,11,12} have also reported overall successful outcomes with open Bankart repair with respect to stability, but have noted some overall loss of shoulder motion in their patients, especially loss of external rotation.

Moreover, patients with multidirectional instability due to capsular laxity have been treated with open surgical techniques. Neer and Foster¹³ originally described the inferior capsular shift with a laterally based T-shaped capsular incision for treatment of patients with inferior and multidirectional instability. Other authors^{14,15,16,17,18} have reported results of a modified open capsular shift technique with good clinical outcomes in terms of stability, but patients in these series also suffered from some degree of postoperative loss of external rotation. Specifically, overhead and throwing athletes had a difficult time returning to their prior competitive level.^15,16,17,18

Overhead throwing athletes are particularly susceptible to shoulder problems and in particular, impingement of the rotator cuff on the posterosuperior glenoid rim and labrum. This phenomenon of “internal impingement” has been well described^{19,20,21,22,23,24,25,26,27} and has been attributed to the loss of anterior glenohumeral stability leading to injury of the anterior capsulolabral complex, particularly during the late cocking phase of throwing with the shoulder in abduction and maximal external rotation.

Care for these patients led to the development of the anterior capsulolabral reconstruction (ACLR)^{22,23,28,29,30,31} at the Kerlan-Jobe Orthopaedic Clinic. The goal was to design a procedure that would restore shoulder stability without compromising shoulder mobility postoperatively. The ACLR is a modification of the Bankart procedure in which a new capsulolabral complex is reconstructed by using suture anchors placed in the anterior glenoid rim and imbricating the capsule and inferior glenohumeral ligament with sutures. However, a capsular shift based on the glenoid side of the joint through a transversely oriented capsulotomy is utilized. Moreover, the native anatomy is preserved as much as possible—no muscle is detached, shortened, or transferred since the subscapularis muscle is split along the line of its muscle fibers.

A careful, detailed history will identify the majority of patients suffering from anterior glenohumeral instability. The apprehension and relocation tests are reliable clinical examination maneuvers to help confirm this diagnosis.²² Initial management consisting of supervised therapy with a specific exercise program is often effective, especially in those patients with subtle glenohumeral instability. Operative intervention is reserved for those patients with persistent symptoms despite adequate conservative treatment. Successful surgery can be performed utilizing either an open or arthroscopic approach. The indications for open anterior stabilization surgery such as
the ACLR are dependent on both patient and surgeon factors. For those patients in whom it is critical to maintain postoperative range of motion, such as overhead throwing athletes, the ACLR provides a reproducible technique to allow the restoration of stability without compromising mobility. Although this may be possible using arthroscopic techniques, currently there are no long-term reports in the literature supporting this practice. Furthermore, some studies have suggested that those patients involved in high-risk contact activities may be better served to have an open reconstruction.^32,33,34,35 In addition, those patients who require revision anterior instability surgery may also benefit from open techniques,^36,37,38 especially if the capsule is thinned or of poor quality. Finally, those patients in whom previous open reconstruction has been successful on one side may prefer to have an open procedure performed on their injured contralateral shoulder.

The skill and experience of the surgeon also play a role in determining whether open surgery is appropriate. Those surgeons whose arthroscopic experience may be limited and who do not feel confident in performing a consistent, reproducible reconstruction with arthroscopic techniques will provide a better service to their patients if open surgical techniques are utilized.

Contraindications to the ACLR procedure include the presence of significant anteroinferior glenoid bone loss and the occurrence of the engaging Hill-Sachs lesion of the posterior humeral head. In these cases, a modified Bristow procedure³⁹ or a glenoid reconstruction procedure using iliac crest bone graft is indicated. The ACLR procedure is also contraindicated when the pattern of instability is mainly posterior or if injury to the posterior labrum is the primary pathology.