Outcomes of Posterior-Stabilized Compared with Cruciate-Retaining Total Knee Arthroplasty

Abstract

The aim of this systematic review is to compare clinical outcome scores, rate of complications, and range of motion (ROM) of posterior-stabilized (PS) and cruciate-retaining (CR) total knee arthroplasties (TKAs) both pre- and postoperatively to establish which of the two kinds of implants have the best efficiency. A comprehensive search was performed of studies comparing CR and PS TKAs on PubMed, OVID/Medline, Cochrane, CINAHL, Google scholar, and Embase databases. Finally, 37 studies were selected with a total of 5,407 knees in 4,445 patients. For the PS knees, the Knee Society Functional Score (KSFS) improved from 44.6 to 77.6 ( = 0.04), extension decreased from 6.6 to 1.8 degrees (-value), and flexion increased from 115.2 to 119.4 degrees ( < 0.00001), compared with the CR knees. No significant difference in the Knee Society objective score (KSOS) ( = 0.82) or complication rates ( = 0.29) was found. The overall complication rate was 3.9%, 213 in 5,407 knees. Surgeons must be careful in interpreting these results, as an improved ROM for the PS group may not correlate to better patient outcomes. This meta-analysis has demonstrated that PS TKA has a statistically significant greater postoperative improvement of KSFS ( = 0.04), flexion ( < 0.00001), and extension ( = 0.02), compared with the CR group. These findings seem to lead the surgeons to prefer the PS design for TKAs especially to achieve a higher postoperative ROM in patients with high functional demands. On the contrary, the CR and PS TKAs have similar results in terms of complications and most of clinical outcomes analyzed in the included studies. Therefore, the long-term follow-up of high-quality randomized controlled trials is needed to clarify which of the two types of prosthesis provide the better clinical outcome and the lower rate of complications for osteoarthritis patients in particular cohorts. This is a systematic review (level II).

Predicting clinical outcomes after total knee arthroplasty from preoperative radiographic factors of the knee osteoarthritis

“…Many studies have assessed the influence of surgical procedures or implant differences on outcomes after TKAs [2][3][4][5][6][7][8][9]. These factors vary depending on the surgeons' experiences or the equipment used.…”

Total Knee Arthroplasty Using a Medial Pivot or Posterior Cruciate-Stabilizing Prosthesis in Chinese Patients

“…57 Traditional knee arthroplasties using PCL preservation (cruciate-retaining [CR]) or PS prostheses are associated with sliding and wear stress as well as instability of prosthesis components, particularly at the level of the cam mechanism in PS prostheses. 21,[58][59][60][61][62][63][64][65] The MP implant has advantages over these traditional prostheses in terms of kinematics and contact area. The MP implant is designed to imitate normal knee flexion kinematics, [66][67][68] which includes the lateral condyle pivoting around the medial condyle and the lateral condyle moving front to back, rotating around the center of the medial side.…”

“…Clinical outcomes include improvements in the Knee Society functional score, decreased extension, and increased flexion. 63 These prostheses are generally considered the gold standard for clinical effect assessment after knee replacement. 64 The PS design achieves a greater postoperative ROM in patients with high functional demands 65,[69][70][71][72] and was selected as the comparator in the present study.…”

Increased Intercondylar Femoral Box Cut-to-Femur Size Ratio During Posterior-Stabilized Total Knee Arthroplasty Increases Risk for Intraoperative Fracture

“…Retrospective studies have shown that these fractures are more likely to occur in the older female population, during bone preparation, impaction of components, and with posterior-stabilized (PS) implants [7][8][9][10][11]. The use of PS implants has been increasing relative to other designs in the United States [4,12], despite no difference in long-term clinical outcomes [13][14][15]. With continued growth of the number of TKA procedures performed annually, mitigating risks is paramount.…”