Periprosthetic Bone Mineral Density Changes After Implantation Of A Short Hip Stem Compared To A Straight Stem
- Conditions
- Osteoarthritis, Hip
- Interventions
- Procedure: Total Hip Arthroplasty
- Registration Number
- NCT03147131
- Lead Sponsor
- University Hospital Ulm
- Brief Summary
The aim of this study is to evaluate periprosthetic bone mineral density (BMD) changes in the proximal femur after implantation of the Fitmore compared to the CLS stem.
- Detailed Description
After power analysis, 140 consecutive patients were prospectively included in the randomisation protocol receiving either a Fitmore short or a CLS straight stem. The short stem was assigned in 57 (37% females) cases and the straight stem in 83 (38% females) hips. Periprosthetic bone mineral density was measured before surgery, 7 days, 3, 12 and 60 months postoperatively, using dual energy x-ray absorptiometry (DEXA). The results of the first postoperative measurement served as the baseline value. Because of the different length of the two prostheses we used adapted Gruen zones to divide the periprosthetic bone in seven regions of interest (ROI) with equal length in the proximal zones 1,2,6 and 7, only the regions 3 and 5 featured different sizes. Clinical results were recorded using the WOMAC and the Harris hip score (HHS).
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 126
- Primary or secondary osteoarthritis of the hip
- written informed consent
- indication for cementless total hip arthroplasty
- previous surgery in the same hip
- femoral fracture
- metabolic bone disease
- drugs affecting bone quality
- contralateral THA within the study period
- infectious disease or bony tumor
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Fitmore short stem Total Hip Arthroplasty Intervention: Total hip arthroplasty with an uncemented femoral short stem, the Fitmore short stem (Zimmer, Warsaw, USA). Furthermore, an uncemented cup (Allofit, Zimmer, Warzaw, USA). Device: Fitmore Short Stem CLS straight stem Total Hip Arthroplasty Intervention: Total hip arthroplasty with an uncemented femoral straight stem, the CLS short stem (Zimmer, Warsaw, USA).Furthermore, an uncemented cup (Allofit, Zimmer, Warzaw, USA). Device: CLS Straight Stem
- Primary Outcome Measures
Name Time Method Stem specific stress shielding of a short compared to a straight hip stem Five years postoperatively Periprosthetic Bone Mineral Density changes around a total hip arthroplasty stem
- Secondary Outcome Measures
Name Time Method Clinical Outcome after short compared to straight stem THA Five years postoperatively Clinical outcome measured with the Harris Hip Score and the WOMAC