What is the management for a comminuted fracture of the humeral head?

Management of Comminuted Humeral Head Fractures

For comminuted three-part proximal humerus fractures, proceed with open reduction and internal fixation or conservative treatment; for four-part fractures, perform primary hemiarthroplasty due to high risk of avascular necrosis. 1

Initial Diagnostic Workup

• Obtain standard shoulder radiographs including AP views in internal and external rotation plus an axillary or scapula-Y view to assess fracture pattern and displacement 2
• Order CT without contrast when radiographs show comminuted fractures, as CT is superior for characterizing complex fracture patterns and can change clinical management in up to 41% of proximal humeral fractures 2
• Use three-dimensional volume-rendered CT images to better characterize fracture patterns and humeral neck angulation, which directly affects functional outcomes 2

Treatment Algorithm Based on Fracture Classification

Three-Part Fractures

• Choose between open reduction with internal fixation (ORIF) or conservative treatment, both yielding favorable outcomes with mean Constant scores of 83-91 points for ORIF and 78 points for conservative management 1
• ORIF is preferred when anatomical reduction can be achieved and patient factors support surgical intervention 1

Four-Part Fractures

• Perform primary hemiarthroplasty as the definitive treatment, achieving mean Constant scores of 74 points compared to 54 points for conservative treatment and 52 points for ORIF 1
• The vascular supply to the humeral head fragment is critically compromised in four-part fractures, creating high risk for osteonecrosis that makes prosthetic replacement superior 1
• Use tuberosity-overlapping fixation technique by reducing tuberosities to overlap the humeral shaft by approximately 1 cm and fixing with cable wire, achieving 88% bone union rates 3

Fractures with Greater Tubercle Involvement

• Address rotator cuff tears during surgical fixation, as up to 40% of humeral head fractures have complete rotator cuff tendon tears 2
• For unstable greater tubercle fragments after intramedullary fixation, stabilize with absorbable sutures through extended surgical approach, anchoring fragments to the shaft 4

Critical Management Considerations

• Assess neurovascular status immediately and continuously, as vascular compromise can lead to permanent nerve and muscle dysfunction 2
• Do not delay rotator cuff repair beyond 4 months if surgical fixation is not performed, though delays up to this timeframe have not shown adverse outcomes 2
• Avoid MRI for acute fracture characterization, as it is inferior to CT for evaluating complex fracture planes 2
• Reserve MRI without contrast for assessing rotator cuff integrity in patients with proximal humeral fractures managed non-operatively 2

Post-Operative Protocol

• Immobilize with appropriate orthosis for 3 weeks following surgical fixation 4
• Initiate intensive rehabilitation after immobilization period to optimize functional recovery 4
• Monitor for bone union which typically occurs at 4-5 months post-operatively with proper fixation techniques 3

Common Pitfalls to Avoid

• Do not attempt ORIF on four-part fractures expecting outcomes comparable to hemiarthroplasty, as the compromised vascular supply makes osteonecrosis highly likely 1
• Do not rely solely on radiographs for surgical planning in comminuted fractures, as CT provides essential information that changes management 2
• Do not perform CT arthrography acutely, as glenohumeral hemarthrosis obscures soft-tissue structures and contrast obscures fracture planes 2