Alumina-on-alumina in THA: a multicenter prospective study

Area of Science:

• Orthopedic surgery
• Biomaterials science
• Medical device research

Background:

• Osteolysis is a significant complication following total hip arthroplasty, often leading to revision surgery.
• Alumina-on-alumina bearing surfaces have been investigated as a strategy to minimize wear and reduce osteolysis.
• Hydroxyapatite-coated stems are used to promote bone integration.

Purpose of the Study:

• To prospectively evaluate the clinical and radiographic outcomes of alumina-on-alumina total hip arthroplasty.
• To assess the incidence of osteolysis, loosening, and revision rates associated with this implant type.
• To determine the survivorship and functional results of alumina-on-alumina prostheses at a minimum of 3 years follow-up.

Main Methods:

• Prospective follow-up of 288 patients (319 hips) with alumina-on-alumina cups and hydroxyapatite stems.
• Minimum follow-up of 3 years (mean 4.7 years, range 3-8 years).
• Evaluation of revision rates, clinical outcomes, radiographic findings (loosening, wear), and patient-reported noise.

Main Results:

• Cumulative probability of avoiding revision for any cause was 97% (95% CI, 94.7%-99.1%).
• Five cups (one with liner fracture) and two stems required revision.
• No patient reported hip noises; however, five non-revised patients showed radiographic cup loosening. No linear femoral head penetration was observed.

Conclusions:

• Alumina-on-alumina prostheses demonstrate reasonable outcomes at 5 years, with a low revision rate.
• While wear appears reduced, radiographic cup loosening in some cases warrants continued monitoring.
• Long-term follow-up is essential to confirm if reduced wear translates to less osteolysis and loosening.