Influences of fit and fill following hip arthroplasty using a cementless short-stem prosthesis.
BACKGROUND
The purpose of this study consisted in examining the effects of fit and fill ratio of the Metha prosthesis (BBraun, Aesculap, Tuttlingen, Germany) on radiological and clinical outcomes at a follow-up of 1 year.


METHODS
40 patients were included. Fit and fill ratio measurements, radiological and clinical examinations were performed preoperatively and postoperatively. Correlations were established between fit and fill ratio, and potential factors like sex, age, body mass index, Harris Hip Score and changes of radiological signs.


RESULTS
The whole cohort (100%) had a tight fit and fill ratio (>0.8) at the proximal level and at each follow-up. "Champagne-flute" configuration provoked high distal tight-fit and fill ratio. Poor distal fit and fill ratio compared to the proximal and the mid-stem level was measurable at each follow-up (p < 0.05). Correlations between fit and fill ratio and preoperative femur configurations were detectable.


CONCLUSIONS
Implanting the Metha prosthesis induces tight fit and fill ratio at the proximal and coated sections. Preoperative femur configuration should be considered to achieve best fit and fill situation and therefore excellent primary stability. In most cases "normal" and "stove-pipe" configurations provide good proximal fit and fill. Since "champagne-flute" configuration induces undesirable tight distal fit and fill ratio the size of the Metha (®) stem should be adequately increased to achieve a more proximal load transmission.
Laboratory of Biomechanics, Justus-Liebig-University Giessen, Paul-Meimberg-Strasse 3, 35392, Giessen, Germany. Alexander.Jahnke@ortho.med.uni-giessen.de.
Alexander
A
Jahnke
Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstraße 33, 35392, Giessen, Germany.
Sandra
S
Engl
Laboratory of Biomechanics, Justus-Liebig-University Giessen, Paul-Meimberg-Strasse 3, 35392, Giessen, Germany.|Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstraße 33, 35392, Giessen, Germany.
Jörn Bengt
JB
Seeger
ATOS Clinic, Center for Knee and Hip Replacement and Regenerative Joint Surgery, Bismarckstrasse 9-15, 69115, Heidelberg, Germany.
Erhan
E
Basad
Laboratory of Biomechanics, Justus-Liebig-University Giessen, Paul-Meimberg-Strasse 3, 35392, Giessen, Germany.|Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstraße 33, 35392, Giessen, Germany.
Markus
M
Rickert
Laboratory of Biomechanics, Justus-Liebig-University Giessen, Paul-Meimberg-Strasse 3, 35392, Giessen, Germany. Bernd.Ishaque@ortho.med.uni-giessen.de.|Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstraße 33, 35392, Giessen, Germany. Bernd.Ishaque@ortho.med.uni-giessen.de.
Bernd Alexander
BA
Ishaque
D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D005260:Female; D005269:Femur / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D011474:Prosthesis Design
Fit and fill; Preoperative femur configuration; Short stem; THA