Objective. Cement thickness of at least 2 mm is generally associated with more favorable results for the femoral component in cemented hip arthroplasty. However, French-designed stems have shown favorable outcomes even with thin cement mantle. The biomechanical behaviors of a French stem, Charnley-Marcel-Kerboull (CMK) and cement were researched in this study. Methods. Six polished CMK stems were implanted into a composite femur, and one million times dynamic loading tests were performed. Stem subsidence and the compressive force at the bone-cement interface were measured. Tantalum ball (ball) migration in the cement was analyzed by micro CT. Results. The cement thickness of 95 % of the proximal and middle region was less than 2.5 mm. A small amount of stem subsidence was observed even with collar contact. The greatest compressive force was observed at the proximal medial region and significant positive correlation was observed between stem subsidence and compressive force. 9 of 11 balls in the medial region moved to the horizontal direction more than that of the perpendicular direction. The amount of ball movement distance in the perpendicular direction was 59 to 83% of the stem subsidence, which was thought to be slip in the cement of the stem. No cement defect and no cement breakage were seen. Conclusion. Thin cement in CMK stems produced effective hoop stress without excessive stem and cement subsidence.
This study aimed to compare the change in health-related quality
of life of patients receiving a traditional cemented monoblock Thompson
hemiarthroplasty compared with a modern cemented modular polished-taper
stemmed hemiarthroplasty for displaced intracapsular hip fractures. This was a pragmatic, multicentre, multisurgeon, two-arm, parallel
group, randomized standard-of-care controlled trial. It was embedded
within the WHiTE Comprehensive Cohort Study. The sample size was
964 patients. The setting was five National Health Service Trauma
Hospitals in England. A total of 964 patients over 60 years of age who
required hemiarthroplasty of the hip between February 2015 and March
2016 were included. A standardized measure of health outcome, the
EuroQol (EQ-5D-5L) questionnaire, was carried out on admission and
at four months following the operation.Aims
Patients and Methods