Changing glenoid version after open reduction of shoulders in children with obstetric brachial plexus palsy.

Twenty-three patients who had obstetric brachial plexus palsy and shoulder subluxation or dislocation that required open reduction and tendon lengthening were entered into a prospective study to evaluate glenoid version after surgery. All the patients had a preoperative computerized axial tomograph and postoperative computed tomography scan of both shoulders at approximately yearly intervals to assess the degree of congruity of the glenohumeral joint and glenoid version. Surgery was performed between 1988 and 1997. There were 11 girls and 12 boys. The mean age was 2 years 5 months (range 8 months-6 years 7 months). The left shoulder was affected in 12 patients and the right shoulder was affected in 11 patients. At mean follow-up of 3 years 7 months, the mean glenoid retroversion for the dislocated shoulder progressively decreased. The difference in glenoid version between the dislocated and the normal side decreased. The angle of glenoid retroversion in the affected shoulders decreased by a mean of 31% after open reduction, and the retroversion continued to improve at 9% per year.