BOSTON — Independent risk factors found among patients with posterior labral tears who developed symptomatic posterior shoulder instability included increased glenoid retroversion, glenoid dysplasia and increased posterior capsular area, according to results presented here.
“The presence of increased glenoid retroversion, the presence of glenoid dysplasia and increased posterior capsular area are independent radiographic risk factors for patients with posterior labral tears who develop symptomatic posterior shoulder instability,” Joseph Galvin, DO, said during his presentation at the Arthroscopy Association of North America Annual Meeting.
Using magnetic resonance arthrograms, Galvin and his colleagues compared the glenoid version, posterior humeral head subluxation and the presence or absence of glenoid dysplasia among 66 patients who underwent arthroscopic isolated posterior labral repair with a group of 56 patients who underwent shoulder arthroscopy for distal clavicle incision.
“We found that our interobserver reliability was good for all measurements except for the total capsular area,” Galvin said.
Univariate analysis results showed that, except for total capsular area, all variables were significantly different between the patient groups. Significant risk factors for posterior labral tears, as well as symptomatic shoulder instability, included increased glenoid retroversion, the presence of glenoid dysplasia and increased axial posterior capsular area, according to results of a multivariate logistic regression.
“Receiver operating characteristic curves were calculated to determine critical cut-off values for posterior capsular area measurements,” Galvin said in his presentation. “We found that posterior capsular area greater than 300 mm2 was 95% specific for posterior shoulder instability.” – by Casey Tingle
Galvin J, et al. Paper #SS-05. Presented at: Arthroscopy Association of North America Annual Meeting; April 14-16, 2016; Boston.
Disclosure: Galvin reports no relevant financial disclosures.