Impact of Robotic Assistance and Fixation Type on Revisions, Complications, and Survivorship Following Total Knee...

With the increasing adoption of both cementless fixation and robotic-assisted techniques in total knee arthroplasty (TKA), it is important to recognize that these approaches carry distinct historical concerns. Earlier generations of cementless implants were associated with higher early failure rates due to inadequate osseointegration, while early robotic systems faced criticism for increased operative times and complication risk. As a result, the current literature presents conflicting evidence regarding the impact of these technologies on early complications and revision rates. This study compares the reoperation rates across 4 TKA cohorts, cemented vs. cementless, with and without robotic assistance.

A retrospective cohort study was conducted using a national administrative claims database. Primary TKA cases were identified using International Classification of Diseases, 10th Revision, and Current Procedural Terminology codes, and 4 cohorts were created: robotic-cemented (R-CEMENT), robotic-cementless (R-CEMENTLESS), conventional-cemented (C-CEMENT), and conventional-cementless (C-CEMENTLESS). Matching was performed based on age, sex, Elixhauser Comorbidity Index, obesity, tobacco use, and diabetes, resulting in 5,210 patients in each group. Outcomes assessed included 1-, 5-, and 10-year ipsilateral reoperations, 30-day emergency department utilizations, and 10-year failure-free survival. χ² tests were used for group comparisons, with p < 0.05 indicating significance.

In the matched cohort (n = 20,840, C-CEMENTLESS, C-CEMENT, R-CEMENTLESS, R-CEMENT; n = 5,210 each), 1-year reoperation rates were lowest in C-CEMENTLESS (0.44%) and R-CEMENTLESS (0.52%), followed by R-CEMENT (0.84%) and C-CEMENT (0.92%) (p = 0.005). At 5 and 10 years, reoperation rates remained lowest in C-CEMENTLESS (0.79%) and R-CEMENTLESS (1.02%), compared with higher rates in C-CEMENT (1.86%) and R-CEMENT (1.71%) (p < 0.001). Kaplan-Meier survival showed 99.7% 5-year survivorship in C-CEMENTLESS and R-CEMENTLESS, versus 99.5% in both cemented groups (p-value < 0.05). No significant differences were observed in 30-day ED utilization (p = 0.11) or readmissions (p = 0.75) across all 4 matched cohorts.

Cementless fixation in TKA, whether robotic or conventional, demonstrated comparable short-term reoperation rates and equivalent long-term survivorship to cemented fixation. Robotic assistance did not significantly affect failure-free survival or healthcare utilization. All 4 cohorts showed excellent 10-year outcomes.