A 24-year single-centre experience with Collum Femoris Preserving stem: clinical and radiological results in young and elderly population

Abstract

Objective: The primary aim was to evaluate the long-term follow-up of Collum Femoris Preserving (CFP) stem, specifically focusing on stem survivorship, complications, as well as on clinical and radiological results. The secondary study objective is an age-based sub-analysis (<65 years vs. ⩾65 years) of long-term results. Materials and methods: We performed a retrospective analysis of patients who underwent CFP implantation between 1997 and 2009. A total of 311 patients (342 hips) were included with a mean follow-up of 15.8 ± 2.2 (range 11–24) years. 2 age groups were analysed: Group-Y (age <65) and Group-E (age ⩾65). Group-Y included 182 hips (mean follow-up 16.3 ± 4.2 years), whereas Group-E included 160 hips (mean follow-up 15.5 ± 3.7 years). Clinical (HHS, OHS and VAS) and radiological data were obtained at final follow-up. Any complications, reoperations, prosthetic components revisions and stem revisions were analysed. Results: According to HSS score, 95% of patients reported excellent/good results (95.6% Group-Y vs. 94.4% Group-E) with an overall stem survival rate of 93.3% (94% Group-Y vs. 92.5% Group-E; p = 0.37). Overall, 87% of stem revisions were performed with primary stems. The rate of prosthetic components revision was 9.9 % (9.9% in Group-Y vs. 10% in Group-E; p = 1). The reoperation rate was 10.8% (11.5% in Group-Y vs. 10.0% in Group-E; p = 0.73). Conclusions: The CFP stem provides good clinical and radiological long-term results with low rate of complications in both young and elderly patients. No significant difference in stem revision and reoperation rates was observed between the 2 groups. Both in elderly and young patients, CFP stem allows revisions to be performed with primary stems.

Short versus conventional straight stem in uncemented total hip arthroplasty: functional outcomes up to 5 years and survival up to 12 years: secondary results of a randomized controlled trial

“…The influence of chance is high because of the limited sample size. Earlier studies reported revision rates between 10% and 27% for the CFP stem [ 11 , 13 ] and 2% and 8% for the Zweymüller stem [ 27 - 30 ]. However, 2 of the revisions in our study were solitary cup revisions.…”

“…No strong conclusions can be drawn on implant survival because this trial was not statistically powered for survival analysis. When looking at observational studies, we also see higher revision rates for the CFP than for the Zweymüller stem [ 11 - 13 , 27 - 30 ]. Although not statistically significant, our RCT supports these findings.…”

“…We previously reported that functional outcomes of the CFP were not superior to the conventional uncemented Zweymüller stem up to 2 years after surgery [9]. Other studies investigating the CFP were mostly cohort studies [10][11][12][13][14]. Available RCTs have small sample sizes and a relatively short follow-up [15,16].…”