Retraction Note: Effect of sagittal femoral component alignment on biomechanics after mobile-bearing total knee arthroplasty

Abstract Purpose To determine the preferred knee in patients with both one total and one unicompartmental knee arthroplasty. Method Patients simply with a unicompartmental (UKA) and total knee arthroplasty (TKA) on contralateral sides were retrospectively screened from three senior knee surgeon’s logs over a 15 year period. Patients safe and free from other diseases to affect gait were approached. A total of 16 patients (mean age 70 ± 8) agreed to ground reaction force testing on an instrumented treadmill at a fair pace and incline. A gender-ratio identical group of 16 healthy control subjects (mean age 67 ± 10) and 16 patients with ipsilateral medial knee OA (mean age 66 ± 7) were analysed to compare. Results Radiographically the mode preoperative Kellgren–Lawrence knee grade for each side was 3. Postoperatively, the TKA side had a mean coronal femoral component alignment of 7° and a mean tibial coronal alignment of 89° with a mean posterior slope of 5° in the sagittal plane. The UKA side had a mean coronal femoral component alignment of 7° and a mean tibial coronal alignment of 86° with a mean posterior slope of 4° in the sagittal plane. In 7 patients, the TKA was the first procedure, while 6 for the UKA and 3 done simultaneously. Gait analysis demonstrated in both walking conditions the UKA limb was the preferred side through all phases of loading (p < 0.05) and nearer to normal than the TKA limb when compared to healthy controls and patients with knee OA. The greatest difference was observed between the transition of weight acceptance and midstance (p = 0.008), when 22% more load was taken by the UKA side. Conclusion By using a dynamic metric of an everyday activity, a distinct gait difference between differing arthroplasty types were established. A more natural loading pattern can be achieved with unicompartmentals as compared to total knees. Level of evidence Retrospective comparative study, Level III.

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Effect of sagittal femoral component alignment on biomechanics after mobile-bearing total knee arthroplasty

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-019-1458-5 ◽

2019 ◽

Vol 14 (1) ◽

Author(s):

Yong-Gon Koh ◽

Jin-Ah Lee ◽

Hwa-Yong Lee ◽

Dong-Suk Suh ◽

Hyo-Jeong Kim ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Femoral Component ◽

Sagittal Alignment ◽

Mobile Bearing ◽

Component Alignment ◽

Collateral Ligament ◽

Joint Contact ◽

Total Knee ◽

Quadriceps Force ◽

Biomechanical Effect

Abstract Background Recently, there has been increasing interest in mobile-bearing total knee arthroplasty (TKA). However, changes in biomechanics with respect to femoral component alignment in mobile-bearing TKA have not been explored in depth. This study aims to evaluate the biomechanical effect of sagittal alignment of the femoral component in mobile-bearing TKA. Methods We developed femoral sagittal alignment models with − 3°, 0°, 3°, 5°, and 7°. We also examined the kinematics of the tibiofemoral (TF) joint, contact point on the TF joint, contact stress on the patellofemoral (PF) joint, collateral ligament force, and quadriceps force using a validated computational model under a deep-knee-bend condition. Results Posterior kinematics of the TF joint increased as the femoral component flexed. In addition, contact stress on the PF joint, collateral ligament force, and quadriceps force decreased as the femoral component flexed. The results of this study can assist surgeons in assessing risk factors associated with femoral component sagittal alignment for mobile-bearing TKA. Conclusions Our results showed that slight flexion implantation may be an effective alternative technique because of its advantageous biomechanical effect. However, excessive flexion should be avoided because of potential loosening of the TF joint.

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Femoral component rotation in mobile-bearing total knee arthroplasty

The Knee ◽

10.1016/j.knee.2006.01.007 ◽

2006 ◽

Vol 13 (4) ◽

pp. 284-289 ◽

Cited By ~ 18

Author(s):

J.G. Boldt ◽

J.B. Stiehl ◽

U. Munzinger ◽

D. Beverland ◽

P.A. Keblish

Keyword(s):

Total Knee Arthroplasty ◽

Femoral Component ◽

Knee Arthroplasty ◽

Mobile Bearing ◽

Femoral Component Rotation ◽

Component Rotation ◽

Total Knee

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Use of Shorter Intramedullary Guide for Ipsilateral Total Knee Arthroplasty following Prior Total Hip Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0037-1603796 ◽

2017 ◽

Vol 31 (04) ◽

pp. 348-351 ◽

Cited By ~ 1

Author(s):

Bradley Webb ◽

Slif Ulrich ◽

Kenneth MacKinlay ◽

Langan Smith ◽

Arthur Malkani

Keyword(s):

Total Knee Arthroplasty ◽

Total Hip Arthroplasty ◽

Femoral Component ◽

Knee Arthroplasty ◽

Hip Arthroplasty ◽

Limb Alignment ◽

Component Alignment ◽

Total Hip ◽

Significant Difference ◽

Total Knee

AbstractAlignment after total knee arthroplasty (TKA) plays an important role with respect to patient satisfaction and implant survivorship. In patients undergoing ipsilateral TKA with prior total hip arthroplasty (THA), the femoral intramedullary (IM) guide cannot be fully inserted into the femoral canal because of the prior THA. The purpose of this study was to determine the effect of femoral component alignment using a shorter IM guide during TKA in patients with an ipsilateral THA. We identified 42 patients undergoing ipsilateral TKA with the use of a short IM guide in the setting of a prior THA. A matched cohort group was identified from our total joint registry that included 42 patients who underwent primary TKA. The surgical goal was to achieve 5 degrees of valgus on the femoral side and 0 degree on the tibial side with an overall postoperative tibial–femoral angle of 5 degrees of valgus. Patients were evaluated clinically using Knee Society pain scores (KSSs), function scores, and with radiography. Both the tibial–femoral limb alignment and the femoral component alignment were compared using Student's t-test. There were no significant differences between the two groups with respect to sex, age, body mass index (BMI), pre- and postoperative KSSs. There was a statistically significant difference between the two groups with respect to radiographic tibial–femoral limb alignment, 4.33 degrees of valgus in the short stem THA–TKA group versus 5.4 degrees of valgus in the TKA group (p < 0.04); however, this difference did not correlate to a difference in postoperative outcomes. An adequate tibial–femoral component alignment was achieved in patients undergoing ipsilateral TKA with prior THA using a shortened IM femoral guide.

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