AANA Lab Course 1002 -3rd Annual Fellows/Chief Residents-Posterior Glenoid Bone Block Augmentation-Josef K. Eichinger, M.D.

Posterior Glenoid Bone Block Augmentation-Josef K. Eichinger, M.D.

Pdf Summary

This presentation by Dr. Josef K. Eichinger discusses the challenges and treatment options for posterior shoulder instability in the setting of glenoid dysplasia, illustrated through a case of a 24-year-old military policeman with dominant arm posterior shoulder instability. The patient experienced significant pain and functional limitation, unable to perform his job or raise his sidearm without pain. Clinical examination revealed positive posterior apprehension and jerk tests, crepitus on posterior drawer testing, and normal rotator cuff strength. Imaging showed substantial glenoid retroversion (23 degrees), loss of normal glenoid contour, enlarged and torn labrum with cyst formation, and 90% posterior humeral head subluxation.<br /><br />An initial arthroscopic posterior labral repair with three double-loaded suture anchors was performed; however, the patient had recurrence of symptoms and persistent posterior subluxation at 8 weeks post-op despite compliance and no new injury. The presentation considers treatment options including glenoid osteotomy (to correct biomechanical deficiency), arthrodesis (which sacrifices shoulder motion and career), revision arthroscopic repair (less favorable due to biomechanical predisposition to failure), and posterior glenoid bone grafting (treats bone loss but not version).<br /><br />Various graft options for glenoid augmentation are reviewed: distal tibia allograft, iliac crest bone graft, and distal clavicle autograft, each with different technical considerations, biological potential, and morbidity. Literature is cited supporting the use of distal tibial allograft reconstruction in shoulder instability (Provencher 2017) and scapular spine autograft as a potential graft source (Rohman 2019). Surgical techniques discussed include arthroscopic preparation of the glenoid, graft insertion underneath the labrum and capsule, and repair to render the graft extra-articular.<br /><br />The presentation also addresses bailout strategies such as mini-open or open incision. A second case illustrates a patient with glenohumeral arthritis and posterior instability treated with total shoulder arthroplasty complicated by glenoid retroversion. Overall, this work highlights complex decision-making in managing posterior shoulder instability in glenoid dysplasia, emphasizing graft selection, surgical technique, and the biomechanical challenges influencing outcomes.

Keywords

posterior shoulder instability

glenoid dysplasia

arthroscopic posterior labral repair

glenoid retroversion

posterior humeral head subluxation

glenoid osteotomy

posterior glenoid bone grafting

distal tibia allograft

iliac crest bone graft

total shoulder arthroplasty