What is the appropriate management for a patient with a painful right hip arthroplasty (artificial hip replacement) after a recent surgery in 2023?

Management of Painful Right Hip Arthroplasty

For a patient with a painful right hip arthroplasty performed in 2023 with normal radiographic findings, the appropriate management should focus on identifying and treating non-mechanical causes of pain, as the imaging shows proper component positioning without signs of loosening or fracture.

Radiographic Assessment

The current radiographic evaluation shows:

• Normal position of prosthetic femoral head relative to acetabular component
• No signs of resorption or fracture along prosthetic components
• No widening of pubic symphysis
• Overall normal appearance of the arthroplasty in standing position

Diagnostic Algorithm for Painful Hip Arthroplasty

Step 1: Rule Out Infection

• Serum inflammatory markers (ESR, CRP)
• Joint aspiration if inflammatory markers are elevated
• Consider combined leukocyte and marrow imaging if infection is suspected (specificity 88-100%) 1

Step 2: Advanced Imaging

• CT with metal artifact reduction (CT-MAR) to evaluate for:

  • Subtle component loosening (CT-MAR sensitivity 84.85% vs 33-51% for radiographs) 1
  • Osteolysis not visible on plain radiographs
  • Liner wear or component malposition

• Bone SPECT/CT if CT is negative

  • Can change management in up to 68% of patients with persistent pain 1
  • Can identify non-hip causes of pain (e.g., spine pathology)

Step 3: Pain Management

• Multimodal analgesia with:
  • Paracetamol/acetaminophen
  • NSAIDs or COX-2 inhibitors (if not contraindicated)
  • Consider single dose of dexamethasone 8-10mg IV for anti-inflammatory effect 1

Step 4: Management Based on Diagnosis

If No Mechanical Issue Identified:

1. Physical therapy focused on hip strengthening and gait training
2. Avoid intra-articular injections if possible (may increase infection risk if revision needed) 1
3. Consider pain management consultation for non-mechanical pain

If Mechanical Issue Identified:

1. For component loosening: Revision surgery
2. For periprosthetic fracture: Surgical fixation
3. For infection: Two-stage revision with antibiotic spacer

Important Considerations

• Timing: Early complications after THA can be safely addressed with immediate revision if needed 2

• Avoid delay if mechanical issue identified: Delaying revision for bone loss, deformity, or instability can increase technical difficulty and worsen outcomes 1

• Common pitfalls:

  • Failing to consider spinopelvic parameters in patients with spinal deformity (can lead to instability despite "safe zone" component positioning) 3
  • Delaying treatment of infection (can lead to progressive bone loss, with 68% of patients experiencing femoral bone loss and 43% experiencing acetabular bone loss during treatment) 4
  • Missing non-hip sources of pain (lumbar spine pathology can refer pain to the hip)

• Patient expectations: Discuss that 8-19% of patients may experience persistent pain after THA despite technically successful surgery 5

If the pain persists despite normal imaging and initial management, a systematic approach to identify less common causes should be pursued, including evaluation for adverse local tissue reactions, tendinopathies, or referred pain from other sources.