Learning curve of robot-assisted total knee arthroplasty and its effects on implant position in Asian patients: A prospective study

Abstract

Background Robot-assisted total knee arthroplasty (r-TKA) can reportedly achieve a more accurate implant position than conventional total knee arthroplasty (c-TKA), although its learning curve is controversial. Moreover, there are few studies on Asians with different anatomical characteristics. This study aimed to determine the learning curve for r-TKA and compare implant positions between r-TKA and c-TKA according to the learning curve in Asian patients. Methods This prospective study included 50 consecutive c-TKAs (C group), followed by 50 consecutive r-TKAs using the MAKO robotic system (Stryker, USA). Cumulative summation analyses were performed to assess the learning curve for operative time in r-TKAs. Accordingly, the r-TKA cases were divided into initial cases (I group) and proficiency cases (P group). Femoral and tibial component positions in the coronal, sagittal, and axial planes and lower limb alignment were compared among all groups. Results r-TKA was associated with a learning curve for operative time in 18 cases. Operative time was significantly shorter in the C and P groups than in the I group, with no significant difference between the C and P groups. The I and P groups demonstrated fewer outliers regarding lower limb alignment, femoral component coronal position, axial position, and tibial component sagittal position than the C group, with no significant difference between C and P groups. Conclusion Operative time was not significantly different between r-TKA and c-TKA after the learning curve. Surgeons could expect more accurate and reproducible lower limb alignment and implant position with r-TKA in Asian patients regardless of the learning curve.

Functional alignment maximises advantages of robotic arm‐assisted total knee arthroplasty with better patient‐reported outcomes compared to mechanical alignment

“…Finally, this study included the initial cases from the learning curve of the robotic arm‐assisted system. However, a previous study confirmed that the final implant positions and outliers were not significantly different between the initial cases and proficiency cases [16]. Therefore, it was determined to be reliable even though the initial cases were included.…”

“…RTKA is known for its advantages, such as accurate implant positioning and fewer outliers. Jung et al [16] confirmed that RTKA resulted in fewer position errors in the sagittal tibial component and femoral component rotation as well as fewer outliers in the hip‐knee‐ankle angle, coronal femoral component position, sagittal tibial component position and femoral component rotation position. However, the relationship between accurate implant positioning and clinical outcomes remains controversial.…”

Correction: Learning curve of robot-assisted total knee arthroplasty and its effects on implant position in asian patients: a prospective study

“…Correction: BMC Musculoskelet Disord 24, 332 (2023) https://doi.org/10.1186/s12891-023-06422-w Following publication of the original article [1], the authors identified the following minor typographical errors in Tables 1 and 3, which are not significant regarding result. Table 1: K-L grade IV (%) -> K-L grade (III/IV) Table 3: HKA angle of proficiency stage: 1/32 (6%) -> 1/32 (3%)…”