Accuracy of bone resection in total knee arthroplasty using CT assisted-3D printed patient specific cutting guides

Abstract

Introduction: We conducted this study to determine if the pre-surgical patient specific instrumented planning based on Computed Tomography (CT) scans can accurately predict each of the femoral and tibial resections performed through 3D printed cutting guides. The technique helps in optimization of component positioning determined by accurate bone resection and hence overall alignment thereby reducing errors.Methods: Prophecy evolution medial pivot patient specific instrumented knee replacement systems were used for end stage arthrosis in all consecutive cases over a period of 20 months by a single surgeon. All resections (4 femoral and 2 tibial) were measured using a vernier callipers intraoperatively. These respective measurements were then compared with the preoperative CT predicted bone resection surgical plan to determine margins of errors that were categorized into 7 groups (0 mm to ≥2.6 mm).Results: A total of 3618 measurements (averaged to 1206) were performed in 201 knees (105 right and 96 left) in 188 patients (112 females and 76 males) with an average age of 67.72 years (44 to 90 years) and average BMI of 32.3 (25.1 to 42.3). 94% of all collected resection readings were below the error margin of ≤1.5 mm of which 90% showed resection error of ≤1 mm. Mean error of different resections were ≤0.60 mm (P ≤ 0.0001). In 24% of measurements there were no errors or deviations from the templated resection (0.0 mm).Conclusion: The 3D printed cutting blocks with slots for jigs accurately predict bone resections in patient specific instrumentation total knee arthroplasty which would directly affect component positioning.

Negligible effect of surgeon experience on the accuracy and time to perform unrestricted caliper verified kinematically aligned TKA with manual instruments

“…Surgeons performing total knee arthroplasty (TKA) and considering different alignment options and instrumentation are interested in the accuracy and time it takes to make the distal and posterior femoral bone resections that determine the setting of the femoral component [ 7 ]. Technology proponents argue that robotic, navigation, and patient-specific instrumentation more accurately hit the femoral target than manual instruments [ 12 , 14 , 22 , 28 ]. Whereas manual instrument proponents argue that technology lengthens the operation, adds expense, and induces stacked errors arising from transforming images into a 3D model, planning the resection planes, and registering instruments [ 1 , 4 , 5 ].…”

A Coronal Landmark for Tibial Component Positioning With Anatomical Alignment in Total Knee Arthroplasty: A Radiological and Clinical Study

“…At present, the commonly used techniques to improve surgical accuracy include computer navigation ( 11 , 12 ), patient-specific cutting guides ( 13 , 14 ), and robotics ( 15 , 16 ). However, previous studies on the cost-effectiveness of these techniques have shown that either technique will increase the cost of each case, which mainly comes from the purchase and maintenance of machinery and equipment, additional preoperative imaging examinations, and limited implant choice of some closed robotic platform.…”

Angular limit for coronal joint deformity correction using intramedullary guidance in total knee arthroplasty. A pilot study

“…Again all those studies used the global axis as the reference axis and none of these investigated a threshold value of correction. Computer assisted guidance for implant positioning has been presented as an advanced solution [41]; a recent meta-analysis displayed better short term functional outcomes when using imageless computer navigation [42][43][44], but without being necessarily correlated with an optimal global alignment. In addition, patient-specific instrumentation (PSI) has been presented to improve accuracy in TKA but there utility is still controversial [45].…”