Table 1 Bivariate analysis of post-discharge 1 year reoperations for patient, operative, and robot-related factors
All | No reoperation | Reoperation | |||||
|---|---|---|---|---|---|---|---|
N | % | N | % | N | % | P value | |
Total # of patients | 320 | 306 | 95.6% | 14 | 4.4% | ||
Female | 168 | 52.5% | 159 | 52.0% | 9 | 64.3% | 0.367 |
Obese (BMI>30 kg/m2) | 143 | 44.7% | 134 | 43.8% | 9 | 64.3% | 0.132 |
CCI, mean (standard deviation, SD) | 1.2 (1.2) | 1.2 (1.2) | 1.4 (1.2) | 0.398 | |||
Prior/current smoker | 32 | 10.0% | 31 | 10.1% | 1 | 7.1% | 0.716 |
Preoperative diagnosis | |||||||
High-grade spondylolisthesis | 193 | 60.3% | 184 | 60.1% | 9 | 64.3% | 0.877 |
Degenerative disk disease | 58 | 18.1% | 56 | 18.3% | 2 | 14.3% | |
Spinal stenosis | 31 | 9.7% | 30 | 9.8% | 1 | 7.1% | |
Degenerative scoliosis | 24 | 7.5% | 22 | 7.2% | 2 | 14.3% | |
Pseudarthrosis | 10 | 3.1% | 10 | 3.3% | 0 | 0.0% | |
Other | 4 | 1.3% | 4 | 1.3% | 0 | 0.0% | |
Robot factors | |||||||
Open (vs. percutaneous) | 56 | 17.5% | 54 | 17.6% | 2 | 14.3% | 0.746 |
Robot time per patient (minutes), mean (SD) | 28.7 (21.3) | 28.5 (21.5) | 32.2 (20.3) | 0.599 | |||
Robot screws per patient, mean (SD) | 5.1 (3.4) | 5.0 (3.4) | 5.7 (3.4) | 0.462 | |||
Robot time per screw (minutes/screw), mean (SD) | 6.6 (3.8) | 6.6 (3.9) | 6.1 (1.9) | 0.668 | |||
Robot system | |||||||
Renaissance | 164 | 51.3% | 160 | 52.3% | 4 | 28.6% | 0.103 |
X | 156 | 48.8% | 146 | 47.7% | 10 | 71.4% | |
Other operative factors | |||||||
Prior spine surgery | 27 | 8.4% | 26 | 8.5% | 1 | 7.1% | 0.856 |
Instrumented levels per patient, mean (SD) | 2.8 (0.9) | 2.8 (0.9) | 3.2 (1.4) | 0.272 | |||
Pelvic fixation | 21 | 6.6% | 19 | 6.2% | 2 | 14.3% | 0.233 |
Operative time (minutes), mean (SD) | 126 (92) | 126 (94) | 129 (58) | 0.924 | |||
Any intraoperative robot-related complication (patients have ≥1 complication) | 11 | 3.4% | 10 | 3.3% | 1 | 7.1% | 0.437 |
Exchange of malpositioned robot screw | 3 | 0.9% | 3 | 1.0% | 0 | 0.0% | 0.710 |
Robot abandonment | 8 | 2.5% | 8 | 2.6% | 0 | 0.0% | 0.540 |
Due to registration error | 3 | 0.9% | 3 | 1.0% | 0 | 0.0% | 0.710 |
Due to unreachable anatomy | 1 | 0.3% | 1 | 0.3% | 0 | 0.0% | 0.830 |
Other | 4 | 1.3% | 4 | 1.3% | 0 | 0.0% | 0.667 |
Intraoperative dural tear | 0 | 0.0% | 0 | 0.0% | 0 | 0.0% | |
Intraoperative loss of motor/sensory function | 0 | 0.0% | 0 | 0.0% | 0 | 0.0% | |
Return to operating room during same inpatient stay for screw removal and/or exchange | 4 | 1.3% | 3 | 1.0% | 1 | 7.1% | 0.042 |
Other non-robot-related complications | |||||||
Intraoperative dural tear | 3 | 0.9% | 3 | 1.0% | 0 | 0.0% | 0.710 |