Long-term results after posterior open glenoid wedge osteotomy for posterior shoulder instability associated with excessive glenoid retroversion.

Manuel Waltenspül,Karl Wieser,Thomas Häller,Lukas Ernstbrunner,Christian Gerber,Sabine Wyss

doi:10.1016/j.jse.2021.05.028

Abstract

Treatment of posterior shoulder instability (PSI) associated with excessive glenoid retroversion is a rare, challenging problem in shoulder surgery. One proposed technique is posterior open wedge glenoid osteotomy to correct excessive glenoid retroversion as described by Scott. However, this operation is rarely performed, and limited long-term outcomes using this approach are available. The goal of this study was to analyze the long-term outcomes of posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion. Six consecutive patients (7 shoulders) with a mean age of 24 years (range 19-34) were treated with posterior open wedge glenoid osteotomy for PSI associated with a glenoid retroversion greater than 15° and followed up clinically and radiographically at a mean age of 15 years (range 10-19). Recurrent, symptomatic PSI was observed in 6 of 7 shoulders (86%). One necessitated revision with a posterior (iliac crest) bone block procedure and was rated as a failure and excluded from functional analysis. One patient rated his result as excellent, 3 as good, 1 as fair, and 1 as unsatisfactory. Mean relative Constant Score (CS%) was unchanged from preoperation to final follow-up (CS% = 72%) and pain did not significantly decrease (Constant Score = 7-10 points; P = .969). The mean Subjective Shoulder Value (SSV) improved postoperatively, but with 6 patients the improvement did not reach statistical significance (SSV = 42%-67%, P = .053) and the total Western Ontario Shoulder Instability Index averaged 30% at the final follow-up. Mean glenoid retroversion of all 7 shoulders was corrected from 20° (range 16°-26°) to 3° (range -3° to +8°) (P = .018). In the 5 shoulders with preoperative static posterior subluxation of the humeral head, the humeral head was not recentered. All 7 shoulders showed progression of glenoid arthritic changes. Posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion neither reliably restored shoulder stability nor recentered the joint or prevent progression of osteoarthritis. Alternative treatments for PSI associated with excessive glenoid retroversion have to be developed and evaluated.

Highlights

Treatment of posterior shoulder instability (PSI) associated with excessive glenoid retroversion is a rare, challenging problem in shoulder surgery
Glenoid dysplasia was defined on preoperative computed tomographic (CT) arthrography according to the Weishaupt classification,[48] and preoperative glenoid retroversion was assessed according to the Friedman technique.[11]
M, male; F, female; BMI, body mass index; DA, dislocation arthropathy; PSH, posterior subluxation of the humeral head. * Defined on preoperative computed tomographic arthrography according to Weishaupt classification.[47] y Glenoid morphology in primary glenohumeral osteoarthritis according to the modified Walch classification.[2,44] z DA was graded from 1 to 4 according to the modified classification of Samilson and Prieto.[1,38] x PSH was defined as an index >65% according to the modified subluxation index described by Gerber et al.[11]