A computed tomography based study on rotational alignment accuracy of the femoral component in total knee arthroplasty using computer-assisted orthopaedic surgery

Purpose Revision surgery for component malrotation in the painful TKA is a relatively novel indication. The purpose of this study was to assess the benefit of revision TKA for component malrotation with regard to the clinical and functional outcomes. Methods Our retrospective case-control study included 51 patients who underwent revision surgery for malrotation with mean follow up of 42 months. They were equally matched to patients who had surgery for aseptic loosening. Results Knee society scores improved from 44/49 to 75/60 (p<0.001) for the study group and 44/47 to 76/57 (p<0.001) for the control group. There was no statistical difference between the groups, including for VAS scores, narcotic reduction or patient satisfaction. Our study showed that revision surgery for malrotation is as beneficial as surgery for aseptic loosening with regard to clinical and functional outcome. Conclusions We recommend CT in painful TKA to assess component malrotation for which revision TKA is beneficial.

Section: Discussionmentioning

confidence: 99%

The benefit of revision knee arthroplasty for component malrotation after primary total knee replacement

Sternheim

Lochab

Drexler

et al. 2012

“…The use of computer-assisted surgery has also reduced the risk of malalignment associated with minimally invasive surgery (MIS) [5,6], which has potential issues with component malpositioning arising from the limited surgical view [7]. However, there were still errors in component alignment with computer-navigated TKA associated with the jig cutting setting, bone cutting and component implantation [8][9][10][11]. Navigation systems recommend checking for alignment of the bone cutting surface just after cutting the bone.…”

Section: Introductionmentioning

confidence: 99%

Cutting and implanting errors in minimally invasive total knee arthroplasty using a navigation system

Hasegawa

Yoshida

Wakabayashi

et al. 2012

Purpose The purpose of this study was to evaluate the accuracy of bone cutting and implantation in minimally invasive total knee arthroplasty with image-free navigation. Methods The alignment of the tibial and femoral bone resection was measured in 40 knees during surgery. The alignment measurement was repeated after cementing the tibial and femoral components. We evaluated the cutting error and the implanting error. Results The mean tibial cutting errors were 0.5 and 0.7°in the frontal and sagittal planes, respectively. The mean femoral cutting errors were 0.5 and 0.9°in the frontal and sagittal planes, respectively. The mean tibial implanting errors were 1.0 and 0.9°in the frontal and sagittal planes, respectively. The mean femoral implanting error was 0.7°in the frontal plane. Conclusions Computer-assisted navigation was useful in checking the alignment of both bone cut and cementation.

“…Axial alignment of the limb with restoration of the mechanical axis is a determinant of the outcome [2]. A number of studies [3][4][5] have suggested that alignment errors of >3°a re associated with more rapid failure and less satisfactory functional results.…”

Section: Introductionmentioning

confidence: 99%

Are MRI-based, patient matched cutting jigs as accurate as the tibial guides?

Conteduca¹,

Iorio²,

Mazza³

et al. 2012

Purpose The aim of this study is to evaluate the accuracy of VISIONAIRE (Smith & Nephew Inc., Memphis, TN, USA) Patient Matched cutting tibial jigs in comparison with extramedullary (EM) tibial instrumentation by analysing data as detected by intra-operative use of VectorVision knee navigation software from BrainLAB (Redwood City, CA, USA). Methods Twelve patients were selected for unilateral total knee replacement (TKR). They underwent a full-length weight-bearing anteroposterior (AP) radiograph and magnetic resonance imaging (MRI). During surgery, once the EM guides were placed and fixed on the tibia, the orientation in the coronal and sagittal planes was checked by the navigator and then compared with the data obtained by measuring the orientation of VISIONAIRE Patient Matched cutting tibial jigs. An unsatisfactory result was considered an error ≥2°in both coronal and sagittal planes for the tibial component as a possible error of 4°could result. Results In the coronal plane the mean deviation of the EM tibial guides from the ideal alignment (0°) was 0.7±0.39°a nd of the VISIONAIRE was 129±1.55°(P00.22). In the sagittal plane the mean deviation of the EM tibial guides from 3°of posterior slope was −1.62±1.78°and of the VISIONAIRE was +1.16±4.29°(P<0.05). Negative values indicate a more posterior slope from the ideal and positive values an anterior slope. Conclusions This preliminary study documented only a fair accuracy of the method with a consistent risk of error of more of 3°especially in the sagittal plane. We could speculate that the problem in the sagittal plane was due to the fact that the pre-operative protocol does not include a lateral X-ray projection of the knee and only includes an AP standing X-ray of the straight leg and MRI.