Survival of short hip stems with a "modern", trochanter-sparing design - a systematic literature review.

Modern total hip arthroplasty delivers excellent and reproducible results. New implant developments include a wide range of implants with a bone and tissue sparing design, including short femoral stems. This review was performed to provide an overview on the currently published survival results of short stems to allow comparison with the results of traditional hip stems. A literature search was performed to identify publications on short stems with a "modern" trochanter sparing design including implant survival information. Information was collected on the study population, follow-up time, implants used, implant survival and functional scores. The revision rate per 100 observed component years was calculated and compared to data presented in national arthroplasty registries. The methodological quality was assessed by employing a score specific to survival assessment of hip stems. In the course of 16 individual searches in EMBASE and Medline, 460 potentially eligible articles were identified. After thorough screening, 14 articles were deemed applicable. The variability in quality of the publications was high. No association between survival outcome and publication quality was apparent. The total revision rate over all studies was found to be 0.38 per 100 component years with endpoint "stem revision for any reason". The survival rate of these stems is encouraging and appears to be comparable with that of more traditional uncemented stems. However, only few mid-term and long-term studies are available. Reports with longer follow-up are needed to draw further conclusions.