Computed Tomography-Based Robotics Are More Accurate than Manual Instruments in Achieving Sagittal Alignment Targets...

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiographic Imaging

Background:

• Implant malalignment in total knee arthroplasty (TKA) can lead to implant failure and patient pain.
• Robotically-assisted total knee arthroplasty (RA-TKA) shows promise for improved accuracy over manual techniques (M-TKA).

Purpose of the Study:

• To compare the accuracy of RA-TKA versus M-TKA in achieving specific coronal and sagittal alignment targets in TKA.
• To evaluate the incidence of radiographic outliers in both RA-TKA and M-TKA procedures.

Main Methods:

• A comparative study involving 201 RA-TKAs and 365 historical M-TKAs performed by the same surgeons.
• Coronal and sagittal component alignments were assessed using radiographs, measuring angles and offsets.
• Univariate analyses were used to compare the proportions of radiographic outliers between the two groups.

Main Results:

• RA-TKA achieved higher accuracy for all four sagittal and two of three coronal alignment targets compared to M-TKA.
• The RA-TKA group had significantly fewer radiographic outliers for multiple alignment parameters (P < 0.01).
• A higher proportion of RA-TKA patients had no outliers (58.2% vs 35.2%) and fewer had multiple outliers (5.5% vs 25%) compared to M-TKA.

Conclusions:

• RA-TKA is more effective than M-TKA in achieving desired coronal and sagittal alignment in TKA.
• The enhanced accuracy of RA-TKA has the potential to improve surgical outcomes and reduce complications associated with malalignment.