Standard versus high-flexion posterior stabilized total knee prostheses

This meta-analysis compared clinical outcomes between standard and high-flexion posterior-stabilized total knee prostheses to evaluate which type of total knee prosthesis was superior. Randomized, controlled trials published until October 2013 comparing standard and high-flexion posterior-stabilized total knee prostheses were reviewed. Methodologic quality was assessed with the Physiotherapy Evidence Database scale. After data extraction, the authors compared results with fixed effects or random effects models, depending on the heterogeneity of the included studies. Eight randomized, controlled trials involving 660 patients met the predetermined inclusion criteria. No statistically significant differences between patients undergoing standard and high-flexion posterior-stabilized total knee prostheses were noted in postoperative range of motion (ROM) (weighted mean difference, -1.43; 95% confidence interval [CI], -4.52 to 1.67; P=.37); flexion angle (weighted mean difference, 0.54; 95% CI, -3.75 to 4.84; P=.80); Knee Society Score (weighted mean difference, 0.92; 95% CI, -0.64 to 2.48; P=.25); Hospital for Special Surgery knee score (weighted mean difference, 0.57; 95% CI, -0.42 to 1.55; P=.26); or Knee Society function score (weighted mean difference, 1.00; 95% CI, -1.49 to 3.49; P=.43). No statistical difference was found between the 2 prosthesis types in complications, involving 21 cases in the standard group and 14 cases in the high-flexion group. The current findings confirm that high-flexion posterior-stabilized total knee prostheses are not superior to standard prostheses in terms of ROM, flexion angle, knee scores, or complications with 5 years or less of follow-up.