All-Polyethylene Tibial Components in Total Knee Replacement: Early Failures

In total primary knee replacement surgery, the use of all-polyethylene tibial (APT) components has many advantages, including no backside wear and no linear dissociation. In addition, the greater polyethylene thickness permits more conservative bone resection compared with that for metal-backed components, with a lower unit cost and similar functional results. Thus, the use of an APT in primary total knee arthroplasty remains an attractive option. This is a review of 158 patients who underwent primary knee replacement using APT components from a single manufacturer. Data collection included age, American Society of Anesthesiology physical status classification, body mass index (BMI), type of deformity, the presence of diabetes mellitus, rate of revision, and characteristics associated with early failure of the components. Average follow-up time was 40 months. The revision rate for any reason was 5.6%, and the average BMI in revision cases was 37.6. Patients with a higher BMI (≥ 37.6) were significantly more likely to require revision surgery than patients with a lower BMI (p = 0.04). In our sample, high BMI was a contributing factor for early failures in total knee replacements using an APT component. Generally, polyethylene tibial components used for primary knee replacements are safe and effective, with good outcomes and subsequent lower costs to the health care system.