The hip replacement type choice: presentation of difficulty and responsibility about a case

Area of Science:

• Orthopedic Surgery
• Nephrology
• Biomaterials Science

Background:

• Metal-on-metal (MoM) hip resurfacing prostheses gained popularity for young, active patients due to theoretical benefits like bone preservation and reduced dislocation risk.
• Long-term steroid use following kidney transplantation can lead to avascular necrosis of the femoral head, necessitating hip replacement.

Observation:

• A 19-year-old patient with a history of double kidney transplant developed bilateral femoral head necrosis and received MoM hip resurfacing.
• Postoperatively, the patient experienced worsening hip pain, psychiatric issues, and recurrent renal failure, associated with extremely high serum cobalt-chromium (Co-Cr) levels.
• Imaging revealed pseudotumor formation, acetabular cysts, femoral neck thinning, and a periprosthetic fracture, indicative of metallosis.

Findings:

• Revision surgery involved removing extensive metallosis and replacing MoM prostheses with cementless ceramic-ceramic total hip replacements.
• Following revision, the patient's local pain, psychiatric symptoms, and serum Co-Cr levels normalized, enabling a third kidney transplant.
• The improvement suggests a detrimental role of Co-Cr ions in both local tissue reactions and systemic health, including transplanted kidney function.

Implications:

• MoM hip prostheses should be avoided in organ transplant recipients due to potential systemic toxicity and adverse effects on graft function.
• Careful patient selection and consideration of comorbidities, medications, and potential biomaterial interactions are crucial for orthopedic implant success.
• This case underscores the importance of a holistic approach in orthopedic surgery, beyond just implant type, to ensure optimal patient outcomes.