The Knee-Fix study: study protocol for a randomised controlled trial evaluating cemented and cementless components in...

Area of Science:

• Orthopedic surgery
• Biomaterials science
• Clinical trial methodology

Background:

• Aseptic failure in total knee arthroplasty (TKA) is often due to implant loosening, linked to cement mantle quality.
• Cementless TKAs offer potential for osseointegration, but early designs had high revision rates.
• Newer highly porous metal designs may improve fixation, yet randomized data on fully uncemented TKA is limited.

Purpose of the Study:

• To investigate long-term implant survival and patient outcomes of fully uncemented versus cemented total knee arthroplasty (TKA).
• To test the hypothesis that uncemented TKA is as clinically reliable and durable as cemented TKA.

Main Methods:

• A two-arm, single-blinded, non-inferiority randomized controlled trial (Knee-Fix study).
• 160 patients per arm with follow-up at 6 weeks, 6 months, 12 months, 24 months, 5 years, and 10 years.
• Primary outcome: implant fixation assessed by radiolucencies; Secondary outcomes: patient-reported scores (OKS, IKSS, FJS-12, EQ-5D-5L, VAS Pain, Satisfaction, NPS).

Main Results:

• This section is not available in the provided abstract.

Conclusions:

• Cemented fixation is the current gold standard for TKA, but cementless options are increasing.
• Highly porous metal cementless components may enhance biological fixation in TKA.
• This prospective study aims to clarify long-term differences between cemented and uncemented TKA techniques.