Total knee replacement (TKR) design aims to restore normal kinematics with emphasis on flexion range. The survivorship of a TKR is dependent on the kinematics in six-degrees-of-freedom (6-DoF). Stepping up, such as stair ascent is a kinematically demanding activity after TKR. The debate about design choice has not yet been informed by 6-DoF in vivo kinematics. This prospective randomised controlled trial (RCT) compared kneeling kinematics in three TKR designs. 68 participants were randomised to receive either cruciate retaining (CR-FB), rotating platform (CR-RP) or posterior stabilised (PS-FB) prostheses. Image quality was sufficient for 49 of these patients to be included in the final analysis following a minimum 1-year follow-up. Patients completed a step-up task while being imaged using single-plane fluoroscopy. Femoral and tibial computer-aided design (CAD) models for each of the TKR designs were registered to the fluoroscopic images using bespoke software OrthoVis to generate six-degree-of-freedom kinematics. Differences in kinematics between designs were compared as a function of flexion. There were no differences in terminal extension between the groups. The CR-FB was further posterior and the CR-RP was more externally rotated at terminal extension compared to the other designs. Furthermore, the CR-FB designs was more posteriorly positioned at each flexion angle compared to both other designs. Additionally, the CR-RP design had more external femoral rotation throughout flexion when compared with both fixed bearing designs. However, there were no differences in total rotation for either step-up or down. Visually, it appears there was substantial variability between participants in each group, indicating unique patient-specific movement patterns. While use of a specific implant design does influence some kinematic parameters, the overall patterns are similar. Furthermore, there is high variability indicating patient-specific kinematic patterns. At a group level, none of these designs appear to provide markedly different step-up kinematic patterns. This is important for
Increasing incidence of osteoporosis, obesity and an aging population have led to an increase in low energy hip fractures in the elderly. Perceived lower blood loss and lower surgical time, media coverage of minimal invasive surgery and
Total hip arthroplasty (THA) is one of the most successful surgery. However,
Summary Statement. The tensile properties of a number of synthetic fibre constructs and porcine MCLs were experimentally determined and compared to allow the selection of an appropriate synthetic collateral ligament model for use in a kinematic knee simulator. Introduction. As
Patient reported outcome measures (PROMs) are important for assessing the results of lower limb arthroplasty. Unrealistic or uneducated expectations may have a significant negative impact on PROMs even when surgery is technically successful. This study's aim was to quantify pre-operative expectations of Scottish patients undergoing total hip and knee replacement (THR/TKR). 100 THR and 100 TKR patients completed validated questionnaires (from the Hospital for Special Surgery) prior to their operation after receiving standard pre-operative information (booklet, DVD, consultations). Each