Publication:

All polyethylene tibia - results of functional and radiological outcome at 5 years follow-up

Background Earlier, all-polyethylene tibial (APT) components were the only option available for TKA. APT components improved over years and have shown results similar or superior to MBT components with respect to survivorship and rate of complications. This study aimed to assess the functional and radiological outcome of TKA with APT components with 5 years follow-up.

Methods This longitudinal study was conducted in a tertiary care center in Mumbai in year 2018. All patients who underwent TKA with APT components during the year 2012 were included in the study. Total of 147 knees were operated in 120 patients. Ninty patients (111 knees) followed up at 5 years. Preoperative and postoperative assessment of patients was done for function, pain and radiological outcome. Functional scores used were Knee society score, WOMAC osteoarthritis index, Bristol score and Oxford knee score. Visual analogue scale (VAS) score was used for pain assessment. Pre and postoperative X-rays were done and component alignment angles (α, β, γ and δ) were calculated.

Results Statistically significant difference was found in pre and postoperative values of VAS score, knee society score, WOMAC osteoarthritis index, Bristol score and Oxford knee score (p value <0.001). Component alignment angles were found to be same pre and postoperatively. None of the patients had radiologic evidence of loosening of implants.

Conclusions APT components have good to excellent functional outcome and good radiological outcome at 5 years. They are safe in view of radiologic component migration at 5-year follow-up.