Related Experiment Video
Updated: Aug 23, 2026
Individualized Stem-positioning in Calcar-guided Short-stem Total Hip Arthroplasty
Published on: February 27, 2018
[The cement free hollow hip prosthesis to reduce intramedullary pressure]
1Klinik für Orthopädie und Orthopädische Chirurgie des St. Augustinus-Krankenhauses Düren. b_barden.sak-dn@clinet.de
Purpose:
A hollow cementless femoral stem has been developed to reduce intramedullary pressure and fat embolism during implantation.
Methods:
In a prospective randomized clinical study, cementless hip stems (ALPHA-FIT) were implanted in 42 patients (24 women, 18 men, mean age: 65.9 years). In Group I (n=21) a solid standard stem was used. In Group II (n=21) a modified hollow stem was implanted with vertical and longitudinal communicating drill holes opening at the implant surface. During surgery the intramedullary pressure was measured by a cannula fixed distally.
Results:
During stem insertion the mean pressure was 82 mmHg (minimum-maximum, 12-259 mmHg) for Group I and 27 mmHg (minimum-maximum, 0-48 mmHg) for Group II. This difference was statistically significant (t-test, p < 0.00076). The pressure measured in Group II was similar to the base pressure before opening of the intramedullary canal (mean 35 mmHg; minimum-maximum, 4-72 mmHg). In both groups higher pressures were found for opening of the canal, drilling with the smallest drill size and rasping.
Conclusion:
Using the hollow prosthesis, the intramedullary pressure could be reduced significantly. The higher pressures during preparation of the femoral canal need further research.
