Abstract
Abstract
Background
Accurate analysis of the patellar resurfacing is essential to better understand the etiology of patella-femoral problems and dissatisfaction following total knee arthroplasty (TKA). In the current published literature patellar resurfacing is analysed using 2D radiographs. With use of radiographs there is potential for error due to differences in limb positioning, projection, anatomic variability and difficulties in appreciating the cement-bone interface. So, we have developed a CT Scan based 3D modelled technique for accurate evaluation of patellar resurfacing.
Methods
This technique for analyses of patellar resurfacing is based on the pre-operative and pos-operative CT Scan data of the patients who underwent TKA with patellar resurfacing. In the first step, accurately landmarked 3D models of pre-op patellae were created from pre-operative CT Scan data in ScanIP software. This model was imported in Geomagic design software and computational model of post-op patella was created. This was further analysed to determine the inclination of the patellar resection plane, patellar button positioning and articular volumetric restoration of the patella. Reliability and reproducibility of the technique was tested by comparing 3 sets of 10 measurements done by 2 independent investigators on 30 computational models of patellae derived from the data of randomly chosen 30 TKA patients.
Results
The developed technique for analyses of patellar resurfacing is reliable and reproducible. The intraclass correlation co-efficient was >0.90 for the 10 measurements performed by two investigators.
Conclusions
This technique can be used by surgeons and engineers for accurate analysis of the patellar resurfacing especially in patients with persistent patello-femoral problems after TKA.
Declaration of Interest
(a) fully declare any financial or other potential conflict of interest
