What happens if the acetabulum cracks after total hip replacement?

Management of Acetabular Fracture After Total Hip Replacement

Acetabular fracture after total hip replacement requires prompt surgical intervention with revision arthroplasty to prevent significant morbidity and mortality. 1

Clinical Presentation and Evaluation

When an acetabular fracture occurs after total hip replacement, patients typically present with:

• Sudden onset of severe hip pain
• Inability to bear weight
• Visible deformity or leg length discrepancy
• Instability of the hip joint

Immediate Assessment:

• Radiographic evaluation (AP and lateral views) to assess:
  • Fracture pattern and displacement
  • Position of prosthetic components
  • Bone stock quality
  • Evidence of component loosening

Management Algorithm

1. Initial Stabilization

• Appropriate pain management with multimodal analgesia
• Consider peripheral nerve blockade as an adjunct for pain control 2
• Avoid sole reliance on opioid analgesics due to risk of respiratory depression and confusion 2
• Immobilization of the affected limb

2. Surgical Intervention

The definitive treatment depends on fracture pattern and stability:

• For unstable fractures with component loosening:

  • Revision arthroplasty with acetabular reconstruction is necessary 1
  • May require specialized implants and bone grafting techniques

• For stable fractures with well-fixed components:

  • Internal fixation may be considered if the component remains stable
  • Close monitoring for subsequent loosening

3. Surgical Technique for Revision

• Positioning: Supine on fracture table 2
• Approach: Extended or modified approaches may be needed for adequate exposure
• Bone grafting: Impaction bone grafting is often required to address bone deficiency 3
• Component selection: Specialized acetabular components may be needed to address bone loss
• Fixation: Additional screws or augments may be required for stability

Postoperative Care

Postoperative care should include:

• Appropriate pain management
• Antibiotic prophylaxis to prevent infection 4
• Correction of postoperative anemia
• Regular assessment of cognitive function
• Assessment for pressure sores
• Monitoring of nutritional status and renal function
• Wound assessment and care 4

Mobilization Protocol

• Early mobilization is crucial but must be tailored based on reconstruction stability
• Weight-bearing restrictions are typically necessary (often partial or non-weight bearing initially)
• Physical therapy to maintain muscle strength and joint mobility

Complications and Their Management

Common complications include:

• Infection: Requires aggressive antibiotic treatment and possible revision surgery
• Component loosening: May necessitate further revision surgery
• Non-union: May require additional bone grafting and fixation
• Heterotopic ossification: Prophylactic low-dose radiation may be beneficial 5
• Dislocation: May require closed reduction or revision surgery
• Nerve injury: Particularly sciatic nerve, requiring careful monitoring and management 1

Follow-up Protocol

• Radiographic evaluation at 6 weeks, 3 months, 6 months, and 1 year 2
• Regular clinical assessment of pain, function, and mobility
• Long-term surveillance for component loosening or failure

Prognosis

The prognosis depends on:

• Patient factors (age, bone quality, comorbidities)
• Fracture pattern
• Quality of surgical reconstruction
• Postoperative rehabilitation

While challenging, modern techniques of acetabular reconstruction can provide excellent pain relief and functional improvements in most patients 1.

Prevention Strategies

• Careful preoperative planning for primary THR
• Proper selection of procedures and positioning of prostheses
• Bone grafting when necessary during primary surgery
• Attention to cement technique when applicable 6
• Consideration of bone quality and patient factors during implant selection