Introduction An unfused secondary ossification center most common location is the junction of meso- and meta-acromion important to distinguish an os acromiale from fractures of the acromion Epidemiology incidence 8% bilateral in 60% more common in males more common in African American Associated conditions shoulder impingement rotator cuff disease meso-acromion is associated with rotator cuff tendonitis and full thickness tears (in 50%) Prognosis poorer outcomes after rotator cuff repairs in patients with meso-os acromiale Anatomy 3 ossification centers meta-acromion (base) origin of posterior portion of deltoid meso-acromion (mid) origin of middle deltoid pre-acromion (tip) origin of anterior deltoid fibers and coracoacromial ligament Blood supply acromiale branch of thoracoacromial artery Presentation History pain from impingement reduction in subacromial space from flexion of the anteiror fragment with deltoid contraction and arm elevation from motion at the nonunion site (painful synchondrosis) incidental finding on radiographs trauma can trigger onset of symptoms from previously asymptomatic os acromiale Imaging Radiographs recommended views best seen on an axillary lateral of the shoulder CT indications to better visualize the nonunion site to detect degenerative changes (cysts, sclerosis, hypertrophy) Treatment Nonoperative observation, NSAIDS, therapy, subacromial corticosteroid injections indications mild symptoms Operative two-stage fusion indications symptomatic os acromiale with impingement technique direct excision can lead to deltoid dysfunction a two-stage procedure may be required first stage - fuse the os acromiale ± bone graft second stage - perform acromioplasty preserve blood supply (acromiale branch of thoracoacromial artery) tension band wires, sutures, cannulated screws arthroscopic subacromial decompression and acromioplasty indications impingement with/without rotator cuff tear (where the os acromiale is only incidental and nontender) open or arthroscopic fragment excision indications symptomatic pre-acromion with small fragment salvage after failed ORIF results arthroscopic has less periosteal and deltoid detachment better excision results with pre-acromion Complications Deltoid weakness from fragment excision Persistent pain/weakness
QUESTIONS 1 of 3 1 2 3 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ07.156) A 27-year-old man presents with shoulder pain. Radiographs are shown in Figure A and B. What is the most likely cause? Tested Concept QID: 817 FIGURES: A B Type & Select Correct Answer 1 Acute acromial fracture 1% (15/2028) 2 Type IV acromioclavicular separation 1% (15/2028) 3 Deltoid avulsion 1% (12/2028) 4 Failure of fusion between the meso-acromion and pre-acromion 18% (364/2028) 5 Failure of fusion between the meso-acromion and meta-acromion 79% (1605/2028) L 2 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review tested concept This is an AAOS Self Assessment Exam (SAE) question. Orthobullets was not involved in the editorial process and does not have the ability to alter the question. If you prefer to hide SAE questions, simply turn them off in your Learning Goals. (SAE07SM.92) Figures 26a through 26c show the MRI scans of a 47-year-old man who underwent arthroscopic shoulder surgery 6 months ago and continues to have pain despite a prolonged course of rehabilitation. Management should now consist of Tested Concept QID: 8754 FIGURES: A B C Type & Select Correct Answer 1 rotator cuff repair. 30% (98/322) 2 revision acromioplasty. 23% (73/322) 3 fragment excision. 17% (56/322) 4 open reduction and internal fixation. 24% (78/322) 5 continued rehabilitation. 5% (17/322) N/A Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review tested concept
All Videos (1) Podcasts (0) Login to View Community Videos Login to View Community Videos Os Acromiale Amiethab Aiyer General - Os Acromiale A 9/2/2013 3378 views 4.3 (18)