Background:Anatomic glenoid reconstruction involves the use of distal tibial allograft for bony augmentation of the glenoid surface. An all-arthroscopic approach was recently described to avoid damage to the subscapularis tendon and preserve the capsule and labrum.Purpose:To explore and compare change in surgical time between 2 proposed methods used for the treatment of anterior shoulder instability—arthroscopic anatomic glenoid reconstruction (AAGR) and arthroscopic Latarjet (AL)—over successive procedures. We also compared graft positioning on the anterior glenoid surface between the 2 methods.Study Design:Cohort study; Level of evidence, 3.Methods:This was a single-surgeon retrospective review of 54 cases of surgically treated recurrent anterior shoulder instability: 27 had AAGR with distal tibial allograft, while the other 27 had AL. AAGR with the distal tibial allograft was the primary choice for the treatment of anterior shoulder instability; however, AL was performed when tibial allograft was not available from the bone bank. Thus, there was an overlapping period for those 2 procedures. Procedure start and end times were recorded, and duration was calculated. Postoperative 3-dimensional computed tomography scans were reviewed, and graft position was judged to be in the lower third (desired position), middle third, or upper third of the anterior glenoid surface. To assess learning, these data were organized in chronological order of surgery, and each surgical cohort was divided into 3 chronological clusters of 9 patients each. Learning was assessed through change in operative time over successive clusters, change in variability of operative time among clusters, and change in graft positioning among clusters. Statistical analysis comprised a 2-tailed independent-sample t test and the Levene test for equality of variance.Results:Our study found that AAGR was significantly faster to perform than AL in the early (P = .001), middle (P = .001), and late (P = .05) clusters of each cohort. Duration of surgery did not significantly improve across clusters within each cohort (P = .15-.79). There were no significant changes in the variability of surgical time in the AAGR group (P = .09) or the AL group (P = .13). Desired positioning of the bone graft on the anterior glenoid surface (lower third) was identified more commonly in the AAGR cohort.Conclusion:AAGR is faster to learn and perform than AL for the treatment of recurrent anterior shoulder instability with significant glenoid bone loss. The current study found higher rates of desired graft positioning for AAGR clusters.

Background:An arthroscopic technique for anatomic glenoid reconstruction has been proposed for the treatment of glenohumeral bone loss in patients with recurrent shoulder instability. This technique is proposed as an alternative to open techniques as well as to the technically challenging arthroscopic Latarjet procedure. In arthroscopic anatomic glenoid reconstruction, a distal tibial allograft is inserted through a novel far medial portal, superior to the subscapularis tendon and lateral to the conjoint tendon.Purpose:To evaluate the safety of the far medial arthroscopic portal for anatomic glenoid reconstruction in a cadaveric study.Study Design:Descriptive laboratory study.Methods:Ten cadaveric shoulder specimens were dissected after inside-out medial arthroscopic portal insertion in the lateral decubitus position for arthroscopic anatomic glenoid reconstruction. A single observer performed 3 measurements on each specimen with a digital caliper (to the nearest 0.1 mm) from the medial portal to neurovascular structures, and the mean (±SD) and the range were calculated. The anthropometric data of the cadaveric specimens were also collected.Results:The mean distances between the far medial arthroscopic portal and sensitive anatomic structures were as follows: 50.79 ± 13.69 mm from the musculocutaneous nerve, 46.28 ± 9.64 mm from the axillary nerve, 6.71 ± 8.52 mm from the cephalic vein, and 48.52 ± 7.22 mm from the subclavian artery and vein. The mean size of the medial arthroscopic portal was 25.60 mm. In all cases, the subscapularis muscle was intact.Conclusion:The far medial arthroscopic portal for anatomic glenoid reconstruction without a subscapularis split presents a minimal risk to most neurovascular structures during bony reconstruction of the glenoid surface in patients with anterior shoulder instability. The only anatomic structure at risk is the cephalic vein, while the axillary and musculocutaneous nerves are at a safe distance away from the portal, based on previous shoulder arthroscopic portal safety studies in the literature.Clinical Relevance:Arthroscopic anatomic glenoid reconstruction using a distal tibial allograft is increasing in popularity for the treatment of anterior shoulder instability with significant bone loss. Being a relatively new technique, the safety of it has yet to be established. This study aimed to demonstrate the safety of a new portal used for arthroscopic anatomic glenoid reconstruction.