Hydroxyapatite-enhanced tibial prosthetic fixation

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Medical Device Engineering

Background:

• Uncemented tibial components are widely used in total knee arthroplasty (TKA).
• Achieving stable initial fixation is crucial for long-term implant survival.
• Surface modifications, such as hydroxyapatite coating, are explored to enhance bone-implant integration.

Purpose of the Study:

• To compare the fixation stability of different uncemented tibial components.
• To evaluate the effect of hydroxyapatite coating on tibial component migration and fixation.
• To assess the clinical and radiostereometric outcomes of various tibial component designs.

Main Methods:

• Randomized controlled trial involving 60 patients (62 knees) undergoing TKA.
• Four groups were studied: porous-coated Osteonic 7000 (cooled/standard saw), hydroxyapatite-coated Osteonic, and hydroxyapatite Duracon tibial components.
• Clinical evaluation and roentgen stereometric analysis (RSA) were performed at 1 and 2 years post-surgery.

Main Results:

• No significant differences in clinical outcomes were observed among the groups.
• The hydroxyapatite-coated tibial components (Groups 3 and 4) demonstrated significantly less migration and inducible displacement compared to the non-coated component (Group 1).
• One knee in the standard saw group (Group 2) required revision due to tibial component loosening; no revisions occurred in hydroxyapatite groups.

Conclusions:

• Hydroxyapatite coating provides a strong positive effect on uncemented tibial component fixation.
• Implants with hydroxyapatite coating showed no continuous migration, indicating superior initial stability.
• This biomaterial enhancement is a promising strategy for improving the longevity of uncemented tibial components in TKA.