Os Acromionale

synonyms:

Os acromionale is the failure of a portion of bone in the shoulder called the acromion to fuse. During normal development the acromion is formed from 4 separate ossification centers. The separate ossification centers generally fuse together into one bone before age 25.

Os acromionale occurs in 8% of people. It is more common in blacks and males than whites and females. It occurs in both shoulders 1/3 of the time.

Os acromionale is generally an asymptomatic finding found on routine xray. This means that it does not cause any problems. Rarely is causes pain with overhead activity, or pain when sleeping on the shoulder.

Using xrays and physical exams your orthopaedic surgeon can generally determine if you have an os acromionale and if it is causeing your shoulder pain.

Treatment for a symptomatic os acromionale depends on where the os acromionale is in the acromion. Initial treatment is generally rest, physical therapy, ice, NSAIDS, and injections.

Patients who fail to improve with non-operative treatment can consider arthroscopic subacromial decompression with fragment excision for very small fragments or fixing and bone graft larger fragments.

The potential complications of surgery include but are not limited to: nonunion, deltoid dysfunction, painful hardware, incomplete relief of pain, incomplete return of function or motion, incomplete return to sport, need for further surgery, clavicle instability, infections, stiffness, weakness, ectopic calcification, reactive bursitis, clavicle or acromion fracture, CRPS, nerve or vascular injury, fluid extravasation, chondrolysis, hematoma, chondral injury / arthritis, DVT/PE, and the risk of anesthesia including heart attack, stroke and death. Complications are uncommon and the most patients are satisfied with the results of surgery.

Following surgery people generaly are placed into a shoulder immobilizer and begin pendulum range of motion exercises. They follow-up with their surgeon 10-14 days after surgery. The shoulder immobilizer is continued for 6weeks, or until bony union is evident radiographically. It generally takes 8-16weeks for the bone to heal. Physical therapy or a home exercise program focused on range of motion and strengthening is started after surgery. Light free weights may begin after the bone heals followed by progressive sport specific activity. People generally return to full activity and sports 6 months after surgery.

Every person and their particular circumstances are different so the treatment for your shoulder may be different than those discussed. Please read this information carefully. Write down any questions that you have about your shoulder and its treatment and discuss them with your orthopaedic surgeon. Working together you and your orthopaedic surgeon will determine the best treatment for you.

Appointments to discuss Os Acromionale with Dr. Grutter can be made here. If you have continued questions or concerns after seeing your orthopaedic surgeon a second opinion from Dr. Grutter is often beneficial.