# Comparative Outcomes Between Cruciate-Retaining and Posterior-Stabilized Prostheses in Total Knee Arthroplasty

## TL;DR

This study compares two types of knee implants and finds that cruciate-retaining implants lead to better long-term recovery and quality of life in elderly patients.

## Contribution

The study provides new evidence on the long-term functional benefits of cruciate-retaining prostheses over posterior-stabilized ones in TKA.

## Key findings

- PCR patients had better WOMAC scores for pain, stiffness, and physical function at 24 months.
- SF-36 and PROMIS-10 also showed PCR implants led to better physical and mental health outcomes.
- PCR implants showed sustained functional advantages over PS implants in elderly TKA patients.

## Abstract

Introduction

Total knee arthroplasty (TKA) is the definitive surgical treatment for advanced gonarthrosis when conservative measures fail. Among the available implant designs, posterior cruciate-retaining (PCR) and posterior-stabilized (PS) prostheses are widely used, yet their comparative performance in long-term functional recovery and health-related quality of life remains under debate.

Methods

We conducted a prospective observational study involving 48 elderly patients undergoing primary TKA at a tertiary-care center in Mexico. Participants received either PCR (n=27) or PS (n=21) implants based on intraoperative assessment. Patient-reported outcomes were evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index, the 36-Item Short Form Health Survey (SF-36), and Patient-Reported Outcomes Measurement Information System (PROMIS-10) Global Health questionnaire at preoperative, six, 12, and 24 months postoperatively.

Results

Both groups demonstrated improvements in all outcome measures; however, PCR patients consistently achieved better results across the follow-up period. At 24 months, WOMAC scores, which reflect better symptom control with higher values, were superior in the PCR group for pain (77.5 vs. 71.0), stiffness (72.5 vs. 62.5), and physical function (86.5 vs. 82.6). SF-36 also favored PCR in physical functioning (66.5 vs. 64.1), bodily pain (72.1 vs. 70.0), and role-physical (54.0 vs. 51.0). PROMIS-10 confirmed these trends, with higher physical (73.9 vs. 71.3) and mental health scores (75.2 vs. 72.0) among PCR patients at 24 months.

Conclusions

Patients receiving cruciate-retaining prostheses experienced greater and more sustained improvements in pain relief, joint function, and quality of life compared to those with posterior-stabilized implants. These findings support the functional advantage of PCR designs in elderly patients undergoing TKA and highlight the value of long-term, multidimensional outcome assessment using patient-reported outcome measures (PROMs).