The term os-acromiale denotes the failure of fusion of acromial apophysis to the scapular spine. The prevalence of os is considered to be about 8% in the general population with higher prevalence in African Americans and males. The treatment options for a symptomatic os acromiale range from arthroscopic excision to decompression to ORIF and bone grafting. In this study, we reviewed retrospectively patients who had undergone ORIF and bone grafting for a painful os acromiale.

Patients surgically treated for os acromiale from 1998 to 2009 were included in the study. All patients were diagnosed to have a symptomatic os acromiale clinically and radiologically. A pre operative MRI of the affected shoulder was done in all patients. All patients had failed conservative management. The surgical technique was standard in all patients. The rotator cuff was repaired if it was torn. Patients were followed up at 3, 6 and 12 months postoperatively. Post operative X-rays were done at 3 months to assess healing. An ASES scoring was done at the final follow up at a mean of 30.5 months post op.

16 patients with 17 shoulders which included 10 males and 6 females were available for the last follow up. 11 shoulders involved dominant hand, 15 shoulders had a history of trauma. Surgery was performed after an average of 7.2 months of conservative management. 11 out of the 17 shoulders had associated rotator cuff tears. Out of the 6 patients with intact cuff, 2 had associated clavicle fractures and 1 patient had an Acromio clavicular joint dislocation. A clinical and radiographic union was achieved in all patients. Mean ASES score in patients without rotator cuff tear was 89 whereas patients with associated rotator cuff tear had an ASES score of 74. Pain score and percentage ADL score were better in patients without rotator cuff tear (92 and 1.3) as compared to those with a cuff tear (83 and 2.2). There was no significant difference in scores in patients who had second surgery at final follow up. 15 of the 16 patients were satisfied with the surgery and would have the surgery on the other side for a similar problem.

Open reduction and internal fixation of symptomatic os acromiale yields predictable clinical outcome. Bigger studies randomising treatment methods in similar group of patients may be needed to find out the superiority of one method over the other.