# COMPARATIVE STUDY BETWEEN ATK 1a WITH CONSTRICTED POLYETHYLENE VERSUS POSTERO-STABILIZED

## TL;DR

This study compared two types of knee implants and found no significant differences in short-term performance.

## Contribution

The study provides short-term evidence on the performance of constricted polyethylene knee implants compared to standard ones.

## Key findings

- Both implant groups showed similar range of movement above 101° post-surgery.
- Only one implant loosening was observed in the constricted polyethylene group.
- No significant difference in implant loosening was found between the two groups in short-term follow-up.

## Abstract

The objective of the article was to do a comparative study between Smith & Nephew ® prosthesis with constricted polyethylene against the standard in patients submitted to total knee arthroplasty surgery during a short-term follow-up. The aim was to analyze the survival of the related implants due to the range of movement and radiographic aspect.

The sample was divided into two different groups: constricted polyethylene and standard polyethylene. A clinical analysis of the patients was carried out, and it was verified whether implant loosening had occurred.

This study evaluated 61 patients in a period of 2 years, 29 in the constricted polyethylene group. The pre-operative deformities were predominantly considered severe. In the postoperative, the tibial-femoral angle varied on average between 5 – 6° of valgus. The total range of movement in the post-operative was above 101° in both groups. One loosened implant in the constricted polyethylene group was observed.

The patients treated with constricted polyethylene had the same range of movement as the control group. There was no significant difference between both groups related to loosened implants in short-term follow-up.
Level of evidence III; Retrospective study.