Posterior cruciate-retaining versus posterior stabilized total knee arthroplasty: a meta-analysis of randomized controlled trials

Purpose To compare the outcomes between posterior cruciate-retaining and posterior stabilized total knee arthroplasty (TKA) in order to evaluate which approach is superior. Methods Randomized controlled trials (RCTs) comparing posterior cruciate-retaining with posterior stabilized TKA were reviewed which were published up to August 2011. Methodological quality of each included RCT was assessed using the Physiotherapy Evidence Database (PEDro) scale. The relevant data were analysed using Review Manager 5.1. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to determine the quality of the evidence. Results Eight RCTs involving 888 patients with 963 knee joints met predetermined inclusion criteria. The postoperative range of motion (ROM) and flexion angle were 11.07 degrees and 2.88 degrees higher for patients with a posterior stabilized TKA than those with a posterior cruciate-retaining TKA, respectively [ weighted mean difference (WMD), -11.07; 95 % confidence interval (CI), -18.06 to -4.08; p < 0.01 and WMD, -2.88; 95 % CI, -5.63 to -0.12; p = 0.04]. No statistical differences were observed between the two designs for knee society pain score, extension angle, 2- and 5-year knee society score, 2- and 5-year knee society function score and complications after primary TKA. Conclusion Posterior cruciate-retaining and posterior stabilized TKA have similar clinical outcomes with regard to knee function, postoperative knee pain and the other complications. Prosthesis survivorship for both posterior cruciate-retaining and posterior stabilized TKA is satisfactory, and there are no differences between them at short- and middle-term follow-up. Level of evidence II.