Ingrowth surfaces. Plasma spray coating to titanium alloy hip replacements

Area of Science:

• Biomaterials Engineering
• Orthopedic Surgery
• Medical Device Technology

Background:

• Traditional cementless total hip replacements (THRs) utilize sintered bead or diffusion-bonded fiber metal ingrowth surfaces.
• These traditional methods can compromise the fatigue strength of titanium alloy implants, retaining less than 50% of the original strength.
• Plasma spray coatings present a promising alternative for enhancing implant performance and longevity.

Purpose of the Study:

• To evaluate the efficacy and safety of plasma spray coatings on titanium alloy THRs.
• To compare the performance of plasma spray cementless THRs against other cementless and cemented THR designs.
• To assess the fatigue strength retention and clinical outcomes associated with plasma spray coated THRs.

Main Methods:

• Analysis of laboratory data on fatigue strength retention in plasma spray coated titanium alloy implants.
• Review of clinical trial data comparing plasma spray cementless THRs (Mallory-Head) with sintered bead cementless THRs (PCA) and cemented THRs.
• Assessment of short to medium-term follow-up data for clinical outcomes and implant fixation.

Main Results:

• Plasma spray coatings allow titanium alloy implants to retain approximately 90% of their original fatigue strength.
• Laboratory and clinical evidence indicate that plasma spray cementless THRs perform as well as, or better than, other cementless implants.
• Clinical trials demonstrated the superiority of plasma spray cementless THRs over sintered bead designs and equivalent results to cemented THRs.

Conclusions:

• Plasma spray coatings are a safe and predictable option for cementless fixation of titanium alloy THRs.
• This coating technology offers significant advantages in preserving implant fatigue strength.
• Plasma spray THRs demonstrate favorable short to medium-term clinical outcomes, making them a viable alternative in hip replacement surgery.