The authors of Clinical results of conservative versus operative treatment of acromial and scapular spine fractures following reverse total shoulder arthroplasty reviewed their experience with operative and non-operative treatment of patients with acromial or scapular spine fractures after reverse total shoulders (RTSA). These fractures were recognized 30 of 1146 RTSAs, although there was no prospective study of these patients to determine the actual prevalence of this complication. 23 had acromial fractures, and 7 had a scapular spine fracture.

While the indications for internal fixation were not described, 7 had surgery and 23 did not.

The authors could not relate the healing rate to the type of fracture or type of treatment. Neither method of treatment yielded better outcomes and neither successfully restored shoulder comfort and function to the levels achieved by patients without these fractures.

These poor outcomes from a major medical center prompted a literature review to see what we know about this disabling complication. In the presentation below, supporting references can be accessed by clicking on the pub med links.

I. Overview

These fractures occur after about 4% of RTSAs, often within the first year. Many - sometimes conflicting - risk factors for these have been suggested, including advanced age, female sex, osteoporosis, rheumatoid arthritis, rotator cuff tear arthropathy, revision arthroplasty, falls, prior surgery, thin acromion, high glenoid inclination, medialized preoperative center of rotation, use of a long superiorly placed screw during baseplate fixation, increased deltoid length > 1 inch, contact of the acromion with the greater tuberosity, disruption of the scapular ring by transection of the coracoacromial ligament, lower distalization of the humerus, medialization of the center of rotation, and use of a lateralized glenoid.

https://www.ncbi.nlm.nih.gov/pubmed/32506260

https://www.ncbi.nlm.nih.gov/pubmed/32807375

https://www.ncbi.nlm.nih.gov/pubmed/32995915

https://www.ncbi.nlm.nih.gov/pubmed/34659470

https://www.ncbi.nlm.nih.gov/pubmed/33185725

https://www.ncbi.nlm.nih.gov/pubmed/33038496

https://www.ncbi.nlm.nih.gov/pubmed/34488294

https://www.ncbi.nlm.nih.gov/pubmed/31629651

https://www.ncbi.nlm.nih.gov/pubmed/31693743

https://www.ncbi.nlm.nih.gov/pubmed/33027125

https://www.ncbi.nlm.nih.gov/pubmed/31154841

https://www.ncbi.nlm.nih.gov/pubmed/27583005

https://www.ncbi.nlm.nih.gov/pubmed/33677115/

II. Non operative treatment

A. Fractures that occur at or medial to the glenoid face demonstrate high rates of unsatisfactory results and worse clinical outcomes with nonoperative management.

https://www.ncbi.nlm.nih.gov/pubmed/35066119

B. Immobilization with an abduction splint frequently resulted in nonunion or malunion

https://www.ncbi.nlm.nih.gov/pubmed/30241984

C. Nonoperative management was chosen due to a concern that stable fixation would not be obtained with surgery.

https://www.ncbi.nlm.nih.gov/pubmed/20506958

https://www.ncbi.nlm.nih.gov/pubmed/35066119

III. Operative treatment

A. Most of the studies comparing surgical methods were carried out in in vitro using models that do not replicate the osteoporotic bone commonly encountered clinically.

1. Double plating better in comparison of fixation methods in synthetic scapulae

https://www.ncbi.nlm.nih.gov/pubmed/35683515

2. Dorsal plate with lateral hook performed better in cadaver study of fixation methods

https://www.ncbi.nlm.nih.gov/pubmed/32788041

3. Locking compression plate was the best of three plating techniques in sawbones

https://www.ncbi.nlm.nih.gov/pubmed/29996981

B. Most clinical reports of surgical treatment consist of case reports with only a few patients

1. Single case using locked double plating of scapular spine fracture

https://www.ncbi.nlm.nih.gov/pubmed/32913063

2. Single case using plate and screws

https://www.ncbi.nlm.nih.gov/pubmed/33330203

3. 7 type II fractures and 4 type III were treated surgically

https://www.ncbi.nlm.nih.gov/pubmed/21448773

4. Plate and screws used in three cases

https://www.ncbi.nlm.nih.gov/pubmed/29222664

5. Plate in a single case of bilateral fractures

https://www.ncbi.nlm.nih.gov/pubmed/33511198

6. 4 fractures with 50% union rate after internal fixation

https://www.ncbi.nlm.nih.gov/pubmed/25818527

7. Single case of internal fixation

https://www.ncbi.nlm.nih.gov/pubmed/24403763

C. Clinical comparison of operative and non-operative treatment

1. Open reduction-internal fixation was not shown to be clinically superior

https://www.ncbi.nlm.nih.gov/pubmed/30497925

2. Operative treatment was not superior to conservative treatment

https://www.ncbi.nlm.nih.gov/pubmed/35447315

3. 3 surgical and 3 nonoperative – clinically unsatisfactory results

https://www.ncbi.nlm.nih.gov/pubmed/21493106

4. The healing rate was shown to be much higher with a surgical approach. Nevertheless, fracture consolidation did not result in better clinical outcomes compared with nonunion.

https://www.ncbi.nlm.nih.gov/pubmed/34968697

Comment: Acromial and scapular spine fractures complicating reverse total shoulder are not uncommon (occurring in 1 out of 25 cases), and usually lead to major loss in shoulder comfort and function. Currently we do not know either how to prevent or how to treat these fractures.

To add this blog to your reading list in Google Chrome, click on the reading list icon