Arthroscopic Implant-Free Bone Grafting for Shoulder Instability With Glenoid Bone Loss: Clinical and Radiological Outcome at a Minimum 2-Year Follow-up

Background: Posttraumatic anteroinferior shoulder dislocations with concomitant glenoid bone loss show high recurrence rates. The open J-bone graft technique for implant-less anatomic restoration of bony glenoid structure has previously been described, whereas results of arthroscopic techniques are currently not available. Purpose: To evaluate clinical and radiological outcome after arthroscopic anatomic reconstruction of the glenoid for recurrent anteroinferior glenohumeral instability. Study Design: Case series; Level of evidence, 4. Methods: Fifteen shoulders of 14 patients with recurrent anteroinferior shoulder instability were prospectively followed after glenoid reconstruction with a modified arthroscopic, implant-free J-bone graft. Preoperatively, the instability severity index score was documented. Patients were followed for a minimum of 2 years using the Rowe score and the Constant score. Subjective outcome was assessed using a visual analog scale (VAS) for pain and the subjective shoulder value for sports (SSVS); satisfaction with procedure outcome was also rated. Range of motion was recorded. Incidence of recurrent instability, defined as dislocation, subluxation, or persistent apprehensiveness, was documented. Pre- and postoperative (1 day and 3, 12, and 24 months) computed tomographic images were used to evaluate glenoid bone loss, reconstruction of the glenoid, and graft remodeling. Results: All preoperative scores (Rowe score: 57.6 +/- 14.4; Constant score: 70.9 +/- 8.9; VAS: 4.4 +/- 2.6; SSVS: 31.4% +/- 19.5%) were significantly (P <= .02) improved at final follow-up (Rowe score: 98.6 +/- 1.5; Constant score: 96.3 +/- 3.9; VAS: 0.2 +/- 0.6; SSVS: 95.6% +/- 3.8%). The preoperative glenoid area (82.1% +/- 4.5%) was significantly increased immediately after surgery to 99.2% +/- 6.6% (P < .001). After a physiological remodeling process, the glenoid area remained significantly increased at the latest follow-up (89.5 +/- 3.2%, P < .001). J-bone grafting successfully restored glenoid concavity by significantly increasing concavity extent and depth from preoperative (19.8 +/- 2.1 and 0.9 +/- 0.6 mm, respectively) to postoperative (24.0 +/- 2.1 and 2.1 +/- 0.8 mm, respectively) (P < .001). There were no recurrent instabilities. One traumatic graft fracture occurred during the follow-up period. Conclusion: The arthroscopic J-bone graft technique permits minimally invasive reconstruction of anteroinferior glenoid defects and provided excellent early clinical outcome without recurrent instability in posttraumatic shoulder dislocations. A physiological remodeling process leads to restoration of a more natural glenoid anatomy.