No effect of obesity on limb and component alignment after computer-assisted total knee arthroplasty.

Purpose: This retrospective study aimed to determine if computer navigation provides consistent accuracy for limb and component alignment during TKA irrespective of body mass index (BMI) by comparing limb and component alignment and the outlier rates in obese versus non-obese individuals undergoing computer-assisted TKA.

Methods: Six hundred and thirty-five computer assisted total knee arthroplasties (TKAs) performed in non-obese individuals (BMI<30 kg/m(2)) were compared with 520 computer-assisted TKAs in obese individuals (BMI ≥ 30 kg/m(2)) for postoperative limb and component alignment using full length standing hip-to-ankle radiographs.

Results: No significant difference in postoperative limb alignment (179.

Factors contributing to inherent varus alignment of lower limb in normal Asian adults: role of tibial plateau inclination.

Purpose: This prospective study aimed to evaluate radiographically, mechanical or hip-knee-ankle (HKA) axis in healthy, asymptomatic, Asian (Indian and Korean) adults between 20 and 40 years of age to determine the incidence of inherent varus (mechanical limb alignment of >3° varus) and the factors influencing it.

Methods: Three hundred and eighty-eight lower limbs were evaluated using full length, standing hip-to-ankle radiographs in 198 healthy, asymptomatic, Asian (Indian and Korean) adults between 20 and 40 years of age to assess the hip-knee-ankle (HKA) angle, medial proximal tibial angle (MPTA), femoral bowing and femoral neck-shaft angle to determine the incidence of inherent varus (mechanical limb alignment of >3° varus) and the factors influencing it.

Results: Overall, the mean HKA angle was 177.

Which factors increase risk of malalignment of the hip-knee-ankle axis in TKA?

Background: Computer navigation has improved accuracy and reduced the percentage of alignment outliers in TKA. However, the characteristics of outliers and the risk factors for limb malalignment after TKA are still unclear.

Questions/purposes: We therefore addressed the following questions: (1) What is the incidence and characteristics of outliers for postoperative limb mechanical axis (hip-knee-ankle [HKA] angle outside the conventional 180° ± 3° range) and component alignment in TKA? And (2) what are the preoperative clinical or radiographic risk factors for limb mechanical axis malalignment in TKA?

Methods: We retrospectively reviewed the clinical and radiographic records of 1500 computer-assisted TKAs to identify outliers for postoperative HKA axis and component alignment and determined risk factors for malalignment.

How accurate are orthopaedic surgeons in visually estimating lower limb alignment?

This study aimed to determine the accuracy and reliability of visual estimation of limb alignment and knee flexion by orthopaedic surgeons when compared to recordings done by computed navigation. Orthopaedic surgeons attending a national conference were asked to place a lower limb synthetic bone model in 6 positions of the knee in the coronal and sagittal planes. These were simultaneously quantified and recorded by a computer navigation system.

Computer guided restoration of joint line and femoral offset in cruciate substituting total knee arthroplasty.

Purpose: This prospective study aimed to evaluate radiographically, change in joint line and femoral condylar offset with the optimized gap balancing technique in computer-assisted, primary, cruciate-substituting total knee arthroplasties (TKAs).

Methods: One hundred and twenty-nine consecutive computer-assisted TKAs were evaluated radiographically using pre- and postoperative full-length standing hip-to-ankle, antero-posterior and lateral radiographs to assess change in knee deformity, joint line height and posterior condylar offset.

Results: In 49% of knees, there was a net decrease (mean 2.

Simultaneous bilateral versus unilateral computer-assisted total knee arthroplasty: a prospective comparison of early postoperative pain and functional recovery.

Whether simultaneous bilateral TKAs (SBTKAs) are more painful and the postoperative functional recovery slower compared to staged bilateral TKAs or unilateral TKAs are issues that frequently concerns patients. The purpose of the current study was to compare the early postoperative pain, function and recovery in simultaneous bilateral versus unilateral computer-assisted TKA. In this prospective study, 50 consecutive patients undergoing unilateral computer-assisted total knee arthroplasties (TKAs) were compared with 50 consecutive patients undergoing SBTKAs in terms of pain, length of hospital stay and rehabilitative milestones during the immediate postoperative period.