The outcome of total knee arthroplasty (TKA) with severe pre-operative varus deformity is significantly worse than in well aligned knees. Computer navigated TKA has addressed some of the problems by ensuring accurate post-operative alignment. Our aims were to see if navigation could reproducibly correct a varus deformity to 3 degrees of the mechanical axis and to investigate the relationships between the tourniquet time and severity of the preoperative deformity, BMI and a surgeon's experience. The 172 e.motion floating platform TKA's were implanted using the OrthoPilot Navigation system (B Braun-Aesculap, Tuttlingen, Germany). Pre-operative deformity and post-operative alignment were measured by the software. Tourniquet times were recorded automatically. All knees were corrected to within 3 degrees of the neutral axis (mean 0.48 degrees ). Statistically significant relationships between tourniquet time (TT) and degree of pre-operative varus (p<0.001), total number of previous e.motion TKA's performed (p<0.001), and body mass index (p=0.013) were found. A linear relationship between the variables can be expressed as a statistical formula: TT=49.5+PreOp Varus+0.6(BMI)-0.1(total previous). Tourniquet time is measured in minutes and preoperative varus is measured in degrees from the mechanical axis. Total previous is the total number of navigated TKA's implanted by the surgeon. Tourniquet time is increased with larger pre-operative deformities and high BMI and decreased with surgical experience. The formula may give us a method of predicting the length of a procedure for a particular surgical team and may allow us to plan operating lists more accurately.
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http://dx.doi.org/10.1016/j.knee.2008.09.008 | DOI Listing |
BMC Musculoskelet Disord
January 2025
Department of Orthopedic Surgery, The 3rd Hospital of Hebei Medical University, Hebei, Shijiazhuang, 050051, P.R. China.
Background: It is known that open wedge high tibial osteotomy (OWHTO) may lead to progression of patellofemoral degeneration due to descent of the patellar height. However, the difference in patellofemoral joint (PFJ) loads with normal daily activity between uniplane and biplane osteotomies is unclear. The purpose of this study was to reveal the differences in PFJ biomechanics between uniplane and biplane OWHTO using finite element analysis (FEA).
View Article and Find Full Text PDFCureus
December 2024
Department of Orthopaedics and Traumatology, All India Institute of Medical Sciences, Raipur, Raipur, IND.
Knee
December 2024
Department of Orthopaedic Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, PR China.
Background: The optimal soft tissue release technique for severe varus total knee arthroplasty (TKA) remains controversial. The technique of tibial plateau reduction was suggested for severe varus deformity during TKA. The purpose of this study was to evaluate the clinical and radiological outcomes of the technique of tibial plateau reduction.
View Article and Find Full Text PDFJ Exp Orthop
January 2025
Department of Trauma and Orthopaedics, Institute for Locomotion, Sainte-Marguerite Hospital Aix-Marseille University Marseille France.
Purpose: Asymmetric anterior closing-wedge high tibial osteotomy (ACWHTO) allows correction of both excessive posterior tibial slope (PTS) and varus deformity. However, the complexity of this surgery requires a high degree of accuracy, which is less likely to be achieved with standard instrumentations. This study aimed to determine the accuracy of 3D patient-specific cutting guides (PSCGs) to provide the accurate planned correction in the frontal and sagittal planes.
View Article and Find Full Text PDFJ 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).
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