Background: Restoration of normal knee kinematics is key to improving patient satisfaction and functional outcomes after total knee arthroplasty (TKA). However, the effect of preoperative varus-valgus kinematics due to knee osteoarthritis on the postoperative kinematics is unclear. The function of the knee ligament contributes to both knee stability and kinematics. The aim of this study was to evaluate changes in varus-valgus kinematics before and after TKA using a navigation system, in addition to comparing the pre- and postoperative changes in kinematic patterns between cruciate-retaining (CR)- and posterior-stabilized (PS)-TKAs.
Methods: Forty knees treated with TKA were evaluated (CR-TKA 20; PS-TKA 20). Manual mild passive knee flexion was applied while moving the leg from full extension to flexion. The varus-valgus angle was automatically measured by a navigation system at every 10° of the flexion angle, and the kinematics were evaluated.
Results: Kinematic patterns throughout flexion can be classified into five types. The pre- and postoperative kinematic patterns were similar in 60% of patients who underwent CR-TKA, whereas they were similar in only 25% of those who underwent PS-TKA. The mean change in the size of the varus-valgus angle throughout flexion did not differ between CR-TKA and PS-TKA. However, the distribution of changes in the size of the varus-valgus angle differed between CR-TKA and PS-TKA.
Conclusions: We obtained the following results: 1) some patterns of varus-valgus kinematics are noted under unloading conditions despite recovery of neutral alignment in extension and 2) the preoperative varus-valgus kinematic pattern persisted more strongly after CR-TKA than after PS-TKA.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.knee.2015.11.015 | DOI Listing |
Knee Surg Sports Traumatol Arthrosc
December 2024
Sezione di Chirurgia Protesica ad Indirizzo Robotico, Unità di Traumatologia Dello Sport, UOC Ortopedia e Traumatologia, Brescia, Italy.
Purpose: The application of robotics in revision arthroplasty particularly from unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA), is underexplored. The purpose of this study is to describe the surgical technique of an imageless robotic system used in the revision of UKA to TKA and to evaluate short- to mid-term outcomes.
Methods: This prospective study includes 35 patients treated from May 2020 to July 2023.
J Exp Orthop
January 2025
Department of Orthopedics, Balgrist University Hospital University of Zurich Zurich Switzerland.
Purpose: The goals of this study were (1) to assess whether the preoperative difference between modalities and extent of deformity are associated with a higher difference between planned and achieved surgical correction and (2) if they yield a higher probability of intraoperative adjustments.
Methods: Retrospective single-centre analysis of patients undergoing patient-specific instrumented (PSI) total knee arthroplasty (TKA). Preoperative radiographic parameters were analysed on weightbearing (WB) long-leg radiographs (LLR) and nonweightbearing (NWB) computed tomography (CT).
Arch Orthop Trauma Surg
December 2024
Department of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahi-machi Abeno-ku Osaka-city, Osaka, 545-8585, Japan.
Background: The combined anteversion theory is used for implant placement in total hip arthroplasty (THA). While majority of the research emphasizes the precise placement of the acetabular cup, there's less focus on stem alignment. This study aimed to investigate the impact of the discrepancy between the preoperatively planned femoral neck osteotomy level and the actual osteotomy level during surgery on stem alignment.
View Article and Find Full Text PDFJ Exp Orthop
October 2024
Department of Trauma, Hand and Reconstructive Surgery University Hospital Münster Münster Germany.
Purpose: To compare different measurement techniques of the posterior tibial slope (PTS) on lateral radiographs with the actual in situ PTS and evaluate the effect of tibial malrotation and image section length.
Methods: Actual PTS was measured on eight fresh-frozen tibiae using a portable 6-axis measuring arm with an accuracy of ±0.01°.
Knee Surg Sports Traumatol Arthrosc
November 2024
Ramsay Santé, Hôpital Privé Jean Mermoz, Centre Orthopédique Santy, Lyon, France.
Purpose: To determine whether there is a correlation between preoperative coronal varus or valgus laxity and patient-reported outcome measures (PROMs) 2 years after individualised total knee arthroplasty (TKA).
Methods: Records of 150 consecutive patients who received individualised TKA were retrospectively analysed, and 126 with complete pre- and postoperative data were included. Preoperative coronal varus and valgus stress radiographs (15 N load) were taken using a telos stress device with the knee in 5°-10° of flexion.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!