Abstract
Implant malalignment during total knee arthroplasty (TKA) may lead to suboptimal postoperative
outcomes. Accuracy studies are typically performed with experienced surgeons; however,
it is important to study less experienced surgeons when considering teaching hospitals
where younger surgeons operate. Therefore, this study assessed whether robotic-arm
assisted TKA (RATKA) allowed for more accurate and precise implant position to plan
when compared with manual techniques when the surgery is performed by in-training
orthopaedic surgical fellows. Two surgeons, currently in their fellowship training
and having minimal RATKA experience, performed a total of six manual TKA (MTKA) and
six RATKAs on paired cadaver knees. Computed tomography scans were obtained for each
knee pre- and postoperatively. These scans were analyzed using a custom autosegmentation
and autoregistration process to compare postoperative implant position with the preoperative
planned position. Mean system errors and standard deviations were compared between
RATKA and MTKA for the femoral component for sagittal, coronal, and axial planes and
for the tibial component in the sagittal and coronal planes. A 2-Variance testing
was performed using an α = 0.05. Although not statistically significant, RATKA was found to have greater accuracy
and precision to plan than MTKA for: femoral axial plane (1.1° ± 1.1° vs. 1.6° ± 1.3°),
coronal plane (0.9° ± 0.7° vs. 2.2° ± 1.0°), femoral sagittal plane (1.5° ± 1.3° vs.
3.1° ± 2.1°), tibial coronal plane (0.9° ± 0.5° vs. 1.9° ± 1.3°), and tibial sagittal
plane (1.7° ± 2.6° vs. 4.7° ± 4.1°). There were no statistical differences between
surgical groups or between the two surgeons performing the cases. With limited RATKA
experience, fellows showed increased accuracy and precision to plan for femoral and
tibial implant positions. Furthermore, these results were comparable to what has been
reported for an experienced surgeon performing RATKA.
Keywords
total knee arthroplasty - training - accuracy - placement
