Biomechanics of a calcar loading and a shortened tapered femoral stem: Comparative in-vitro testing of primary stability and strain distribution.

Purpose: The most common femoral short stems available on the market can, in principle, be divided with regard to their anchoring concepts into a calcar loading and a shortened tapered design. The purpose of this study was to compare the primary stability and stress-shielding of two short stems, which correspond to these two different anchoring concepts.

Methods: Using seven paired fresh frozen human cadaver femurs, primary axial and rotational stabilities under dynamic load (100-1600 N) were evaluated by miniature displacement transducers after 100,000 load cycles.

Anterior pelvic plane registration accuracy and cup position measurement using ultrasound- and pointer-based navigation in primary total hip arthroplasty.

Background: Incorrect cup positioning in primary total hip arthroplasty is known as a risk factor for early implant failure. The use of navigation systems leads to more accurate cup positioning.

Objective: The aim of this study was to compare the registration accuracy of the anterior pelvic plane and the measurement accuracy of the definite cup position for a pointer computer-assisted orthopaedic navigation system (P-CAOS) and an ultrasound-based navigation tool (US-CAOS) in an intra-individual study design.

Blood cytokine pattern and clinical outcome in knee arthroplasty patients: comparative analysis 5 years after standard versus "hypoallergenic" surface coated prosthesis implantation.

Background and purpose - Metal sensitivity might provoke complications after arthroplasty. Correspondingly, coated "hypoallergenic" implants are of interest but long-term follow-up data are missing. Thus, we assessed immunological and clinical parameters in such patients.

Ion release in ceramic bearings for total hip replacement: Results from an in vitro and an in vivo study.

Introduction: Literature on the potential release of trace elements following implantation of Zirconia-platelet toughened alumina (ZPTA) ceramic components is scant. The present study therefore analysed the in vitro and in vivo potential release of ions from ZPTA bearings.

Material And Methods: An in vitro and in vivo study was conducted.

Ultrasound vs pointer palpation based method in THA navigation: a comparative study.

Intraoperative registration of the anterior pelvic plane is necessary for navigation during total hip arthroplasty (THA). Ultrasound referencing of bony landmarks was implemented in a THA navigation system (OrthoPilot, B. Braun Aesculap; Tuttlingen, Germany) as an alternative to pointer palpation.

OrthoPilot total hip arthroplasty workflow and surgery.

To analyze the workflow and navigation principles of the OrthoPilot total hip arthroplasty (THA) Version 2.0 (B. Braun-Aesculap, Tuttlingen, Germany), a consecutive series of 60 patients was used to compare the navigated intraoperative data and postoperative measurements of stem and cup position.

Consistency of implantation of a total knee arthroplasty with a non-image-based navigation system: a case-control study of 235 cases compared with 235 conventionally implanted prostheses.

The aim of the study was to assess the consistency of the non-image-based navigation system OrthoPilot, Aesculap, Tuttlingen, Germany, in total knee arthroplasty (TKA) implantation in 5 European centers. Two hundred thirty-five TKAs implanted with this navigation system were matched (according to severity of the preoperative coronal deformation and body mass index) to a historical control group of 235 TKAs implanted with a conventional technique. Consistency of implantation was studied on a 3-month postoperative radiological control with coronal long-leg and sagittal standard x-rays.

OrthoPilot cup navigation--how to optimise cup positioning?

Unlabelled: The kinematic cup navigation procedure is a surgically simple technique for improving the precision of cup placement. Without CT scans, a reduction of cup malpositions is possible. The rate of desired cup inclination and anteversion angles is markedly increased as shown by the first results of 147 navigated cups.