What is the recommended management for hip prosthesis pain without injury?

Management of Hip Prosthesis Pain Without Injury

Begin with acetaminophen (1g every 6 hours, max 4g daily) combined with NSAIDs (such as naproxen 500mg twice daily) as foundational therapy, while systematically investigating the underlying cause of pain to guide definitive treatment. 1, 2, 3

Initial Pharmacologic Management

• Initiate acetaminophen plus NSAIDs or COX-2 selective inhibitors as first-line therapy, representing Grade A evidence for musculoskeletal pain management in the prosthetic hip. 1, 3
• Acetaminophen should be dosed at 1g every 6 hours, not exceeding 4g daily, and used cautiously in liver disease. 3
• NSAIDs should be continued regularly for optimal anti-inflammatory effect, not just as-needed dosing. 1
• For naproxen specifically, use 500mg twice daily for chronic pain management (morning and evening doses do not need to be equal). 4
• Opioids carry a Grade D recommendation and should be reserved strictly for rescue analgesia only, never scheduled dosing. 1, 3

Systematic Diagnostic Evaluation

The cause of prosthetic hip pain must be identified through targeted assessment:

• Evaluate for mechanical causes: protruding screws causing soft tissue impingement (iliopsoas muscle, external obturator muscle, sciatic nerve), component loosening, or malposition. 5, 6
• Assess for tendinopathies: iliopsoas tendinitis, greater trochanteric pain syndrome, snapping hip syndrome, and abductor tendinopathy are major causes of debilitating pain that often go unrecognized. 7
• Rule out infection: septic loosening must be excluded before proceeding with conservative management. 6
• Consider osseointegration deficiency, post-traumatic inflammatory response, or allergic reaction as potential contributors. 6

Diagnostic Criteria for Persistent Pain

• Post-operative pain (VAS ≥3) persisting for at least 4 months after surgery, OR new onset pain (VAS ≥3) after the first 4 months, lasting ≥2 months. 6
• Acute pain with VAS score ≥7 should be immediately investigated regardless of timing. 6

Physical Therapy and Rehabilitation

• Either formal physical therapy or unsupervised home exercise is supported after total hip arthroplasty, with high quality evidence and moderate strength of recommendation. 8
• Rehabilitation should address biomechanical deficiencies with neuromuscular training of the hip and lumbopelvic regions. 9
• Activity modification and limitation of aggravating factors are essential components. 9
• Early mobilization should be facilitated by optimal multimodal analgesia. 2

Interventional Considerations

• For suspected iliopsoas tendinitis, diagnostic infiltration of the iliopsoas muscle can be performed, though improvement may be only temporary. 5
• Fascia iliaca block or local infiltration analgesia may be considered for persistent pain when contraindications to basic analgesics exist or in patients with high expected pain levels. 3
• Avoid femoral nerve blocks, lumbar plexus blocks, or epidural analgesia for chronic hip prosthesis pain due to adverse effects outweighing benefits. 1, 2

Surgical Management

• Implant revision is indicated only when septic or aseptic loosening is diagnosed. 6
• For mechanical causes such as protruding screws: removal of offending screws after cup integration can be a conservative and effective strategy, with complete symptom resolution reported. 5
• For refractory tendinopathies not responsive to 3-6 months of conservative management, operative intervention may be necessary (tendon release or repair). 7

Critical Pitfalls to Avoid

• Do not assume treatment failure without proper medication optimization: multimodal analgesia with scheduled acetaminophen and NSAIDs should minimize or eliminate opioid requirements. 1
• Do not overlook screw length and protrusion as a treatable cause of persistent pain—this should be specifically evaluated on imaging. 5
• Do not miss tendinopathies: these are treatable conditions that, when recognized and managed, result in higher surgeon and patient satisfaction. 7
• NSAIDs should be avoided in patients with colon or rectal anastomoses due to potential correlation with dehiscence. 3
• Gabapentinoids should not be used routinely for hip arthroplasty due to potential side effects without proven benefit. 3