Do Patients Really Gain Outcome Benefits When Using the High-Flex Knee Prostheses in Total Knee Arthroplasty? A Meta-Analysis of Randomized Controlled Trials

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Abstract

The purpose of this study was to undertake a meta-analysis to evaluate whether patients really gain outcome benefits when using the high-flex (HF) prostheses in total knee arthroplasty (TKA) compared with standard (STD) implants. Only randomized controlled trials were included in this meta-analysis. After searching PubMed, Embase, Wed of Science and Cochrane Library, 1042 papers were identified and 18 trials were finally eligible for meta-analysis including 2069 knees (1906 patients). We found no statistically significant difference between the two designs in terms of ROM, knee scores (KSS, HSS, WOMAC, and SF-36), patients’ satisfaction and complications. Hence there is currently no evidence to confirm that the use of high-flex prostheses in short-term is superior to the standard prostheses after total knee arthroplasty.

Section snippets

Inclusion Criteria

We only included randomized controlled trials comparing high-flex (HF) prostheses with standard (STD) prostheses in primary TKA, with adequately reported data on range of motion (ROM), Knee Society score (KSS), Hospital for Special Surgery knee score (HSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form (SF)-36, and complications. Any prospective studies, retrospective studies, cadaver studies, letters, comments, case reports, guidelines, and review papers

Study Characteristics

Fig. 1 shows the details about the process of study selection. Our search strategy totally generated 1042 articles. 106 articles were considered potentially eligible for further evaluation after removing duplications and scanning titles and abstracts. After reading the full-texts for detailed evaluation, 18 studies were included based on our inclusion criteria, comprising 2069 knees (1906 patients) in this meta-analysis.

Characteristics and quality assessment of the included 18 studies were

Discussion

Our meta-analysis showed that post-operative ROM was a little higher in HF TKAs compared with STD TKAs in the overall comparison, but there was evident statistical heterogeneity. In the subgroup analysis, both PS-Flex vs. PS group and CR-Flex vs. CR group suggested that there was no significant difference in post-operative ROM when comparing HF and STD TKAs. Moreover, there was also no statistically significant differences in clinical outcomes (KSS, HSS, WOMAC, and SF-36), patient’s

Acknowledgements

All authors have no financial or personal relationships with other people or organizations that could inappropriately influence this work.

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    Source of Funding: This research was funded by the China Health Ministry Program (201302007).

    The Conflict of Interest statement associated with this article can be found at http://dx.doi.org/10.1016/j.arth.2014.11.025.

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