Influence of the compliance of a patient's body on the head taper fixation strength of modular hip implants.

摘要: Abstract Background The strength of the modular fixation between head and stem taper total hip replacement implants should be sufficient to minimise relative motion prevent corrosion at interface. Intraoperatively components are assembled by impaction with a hammer. It is unclear whether effective compliance patient's body modifies interface under assembly. purpose this study was assess influence on strength. Methods Cobalt-chrome ceramic femoral heads were titanium alloy tapers in laboratory impaction. Impaction forces applied constant energy, defined drop height impactor, according standard experimental procedure. patient simulated varying stiffness springs mounted below taper. Pull-off neck measured determine Findings Decreasing spring had no effect peak during assembly or pull-off forces. showed difference metal materials. Interpretation independent taper, indicating that has testing can therefore performed rigid fixation, without accounting for patient.