Details
| Original language | English |
|---|---|
| Pages (from-to) | 2211-2217 |
| Number of pages | 7 |
| Journal | International orthopaedics |
| Volume | 36 |
| Issue number | 11 |
| Publication status | Published - 4 Aug 2012 |
Abstract
Purpose: The cementless Bicontact® total hip arthroplasty (THA) system (AESCULAP AG, Tuttlingen, Germany) was introduced in 1986/1987 and has been in successful clinical use in an unaltered form up to today. Although good long-term results with the Bicontact® stem have been published, it is questionable whether the implant provides the criteria for a state-of-the-art stem regarding proximal bone stock preservation. The purpose of the study was to monitor the periprosthetic bone mineral density (BMD) in a prospective two-year follow-up dual-energy X-ray absorptiometry (DEXA) study. Methods: After power analysis, a consecutive series of 25 patients with unilateral Bicontact® stem implantation was examined clinically and underwent DEXA examinations. Scans of seven regions of interest were taken preoperatively and at one week, six months, and one and two years. Results: One patient required stem revision due to a deep infection. The Harris Hip Score increased significantly by 44 points. The most significant bone loss was observed in the calcar region (R7) in the first six months (-19.2 %). It recovered in the following 18 months to -8.5 %. The BMD in the greater trochanter dropped significantly after six months and remained stable at this level. BMD exceeded baseline values in distal regions and even more in the lesser trochanter region after two years. Conclusions: We conclude that the Bicontact® stem provides adequate proximal bone stock preservation. We observed some signs of stress shielding at the tip of the stem, which is inevitable to some degree in THA with cementless straight stems. However, in this prospective DEXA investigation, we showed that proximal off-loading does not occur after THA with the Bicontact® system. Thus, we believe that this stem is still a state-of-the-art implant.
ASJC Scopus subject areas
- Medicine(all)
- Surgery
- Medicine(all)
- Orthopedics and Sports Medicine
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In: International orthopaedics, Vol. 36, No. 11, 04.08.2012, p. 2211-2217.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - The cementless Bicontact® stem in a prospective dual-energy X-ray absorptiometry study
AU - Lerch, Matthias
AU - Kurtz, Agnes
AU - Windhagen, Henning
AU - Bouguecha, Anas
AU - Behrens, Bernd A.
AU - Wefstaedt, Patrick
AU - Stukenborg-Colsman, Christina M.
N1 - Funding information: The study was undertaken in the subproject D6 of the Collaborative Research Center 599 “Sustainable degradable and permanent implants out of metallic and ceramic materials”. The authors thank the German Research foundation (DFG) for the financial support. The authors declare that they have no conflict of interest.
PY - 2012/8/4
Y1 - 2012/8/4
N2 - Purpose: The cementless Bicontact® total hip arthroplasty (THA) system (AESCULAP AG, Tuttlingen, Germany) was introduced in 1986/1987 and has been in successful clinical use in an unaltered form up to today. Although good long-term results with the Bicontact® stem have been published, it is questionable whether the implant provides the criteria for a state-of-the-art stem regarding proximal bone stock preservation. The purpose of the study was to monitor the periprosthetic bone mineral density (BMD) in a prospective two-year follow-up dual-energy X-ray absorptiometry (DEXA) study. Methods: After power analysis, a consecutive series of 25 patients with unilateral Bicontact® stem implantation was examined clinically and underwent DEXA examinations. Scans of seven regions of interest were taken preoperatively and at one week, six months, and one and two years. Results: One patient required stem revision due to a deep infection. The Harris Hip Score increased significantly by 44 points. The most significant bone loss was observed in the calcar region (R7) in the first six months (-19.2 %). It recovered in the following 18 months to -8.5 %. The BMD in the greater trochanter dropped significantly after six months and remained stable at this level. BMD exceeded baseline values in distal regions and even more in the lesser trochanter region after two years. Conclusions: We conclude that the Bicontact® stem provides adequate proximal bone stock preservation. We observed some signs of stress shielding at the tip of the stem, which is inevitable to some degree in THA with cementless straight stems. However, in this prospective DEXA investigation, we showed that proximal off-loading does not occur after THA with the Bicontact® system. Thus, we believe that this stem is still a state-of-the-art implant.
AB - Purpose: The cementless Bicontact® total hip arthroplasty (THA) system (AESCULAP AG, Tuttlingen, Germany) was introduced in 1986/1987 and has been in successful clinical use in an unaltered form up to today. Although good long-term results with the Bicontact® stem have been published, it is questionable whether the implant provides the criteria for a state-of-the-art stem regarding proximal bone stock preservation. The purpose of the study was to monitor the periprosthetic bone mineral density (BMD) in a prospective two-year follow-up dual-energy X-ray absorptiometry (DEXA) study. Methods: After power analysis, a consecutive series of 25 patients with unilateral Bicontact® stem implantation was examined clinically and underwent DEXA examinations. Scans of seven regions of interest were taken preoperatively and at one week, six months, and one and two years. Results: One patient required stem revision due to a deep infection. The Harris Hip Score increased significantly by 44 points. The most significant bone loss was observed in the calcar region (R7) in the first six months (-19.2 %). It recovered in the following 18 months to -8.5 %. The BMD in the greater trochanter dropped significantly after six months and remained stable at this level. BMD exceeded baseline values in distal regions and even more in the lesser trochanter region after two years. Conclusions: We conclude that the Bicontact® stem provides adequate proximal bone stock preservation. We observed some signs of stress shielding at the tip of the stem, which is inevitable to some degree in THA with cementless straight stems. However, in this prospective DEXA investigation, we showed that proximal off-loading does not occur after THA with the Bicontact® system. Thus, we believe that this stem is still a state-of-the-art implant.
UR - http://www.scopus.com/inward/record.url?scp=84876580211&partnerID=8YFLogxK
U2 - 10.1007/s00264-012-1616-4
DO - 10.1007/s00264-012-1616-4
M3 - Article
C2 - 22864457
AN - SCOPUS:84876580211
VL - 36
SP - 2211
EP - 2217
JO - International orthopaedics
JF - International orthopaedics
SN - 0341-2695
IS - 11
ER -