What is the appropriate management for a nondisplaced fracture of the acromion?

Management of Nondisplaced Acromion Fractures

Conservative management with immobilization in a sling is the appropriate initial treatment for nondisplaced acromion fractures, with close radiographic surveillance to detect displacement that would necessitate surgical intervention. 1, 2

Initial Diagnostic Imaging

• Obtain complete radiographic series including anteroposterior views in internal and external rotation plus an axillary or scapula-Y view to confirm the diagnosis and rule out associated injuries. 1
• The axillary view is critical because AP views alone can miss displacement or associated fractures. 1
• Consider CT imaging to better characterize the fracture pattern, particularly if surgical planning may be needed or if the fracture involves the scapular spine. 1, 3

Conservative Management Protocol

• Immobilize the shoulder in a sling for comfort and fracture protection. 2, 4
• Initiate early gentle range-of-motion exercises after the initial pain subsides, typically within 2-4 weeks, to prevent frozen shoulder. 4
• Avoid overhead activities and direct pressure on the acromion during the healing period. 2

Critical Surveillance Requirements

The major pitfall with nondisplaced acromion fractures is that they can displace secondarily if not adequately protected, particularly in polytrauma patients or with inadequate immobilization. 5, 3

• Obtain repeat radiographs at 2-4 weeks to detect any displacement that occurred during the initial healing phase. 2, 5
• Monitor for persistent pain beyond 4 weeks, which may indicate nonunion or occult displacement requiring CT evaluation. 4, 3
• The mean time to diagnosis of nonunion is 35 months when fractures are initially missed or undertreated, with conservative treatment being the most common cause of delayed diagnosis. 3

Indications for Surgical Intervention

Proceed with open reduction and internal fixation if any of the following develop:

• Fracture displacement detected on follow-up imaging. 5, 6
• Persistent severe pain at 4 weeks without evidence of callus formation on CT. 4
• Concomitant injuries to the superior shoulder suspensory complex (e.g., distal clavicle fracture creating a "floating acromion"). 2, 4
• Active patients where deltoid strength is functionally important and nonunion risk is unacceptable. 2, 5
• Symptomatic nonunion that develops despite initial conservative treatment. 2, 3

Surgical Technique When Required

• A lateral clavicle plate provides excellent fixation for acromion fractures, fitting well on the lateral spine and acromion. 4
• Various plate configurations have been used successfully, with tension band wiring as an alternative in select cases. 3
• Bone grafting should be considered in 73% of operative cases, particularly for established nonunions. 3
• Surgical outcomes are excellent in 79% of cases with adequate follow-up when appropriate fixation is used. 3

Rehabilitation After Surgery

• Provide sling immobilization for 2 weeks postoperatively. 4
• Begin circumduction exercises at 2 weeks, then progress to active movement under physiotherapy supervision. 4
• Aggressive early mobilization is essential to prevent frozen shoulder, which can occur even with optimal surgical treatment. 4
• Full range of motion is typically achieved by 50 days, with radiographic union by 12 weeks. 6

Special Considerations

• Elderly or less active patients may tolerate nonunion better than younger active individuals, making conservative management more acceptable even if nonunion develops. 2
• The nonunion rate with conservative treatment is relatively high, but not all nonunions are symptomatic or functionally limiting. 2
• In polytrauma settings, acromion fractures are frequently missed initially due to more obvious injuries, requiring high clinical suspicion and complete imaging. 1, 3