Robotic surgery (RS) can offer benefits compared to freehand surgery (FS) in the treatment of patients with spinal diseases. The aim of this study was to assess efficacy and safety of RS versus FS in spinal fusion. The outcomes considered were accuracy in the placement of pedicle screws, surgical times, hospital stay, exposure to radiation, and complications.

A systematic review and meta-analysis were performed by researchers at the Instituto de Salud Carlos III (ISCIII). Studies published until June 2019 in the English, Spanish, or French languages were retrieved. The data analyses and risk of bias assessments were undertaken using RevMan 5.3.

Eight randomized controlled trials including 610 patients (RS: 308, FS: 302) were found. The mean age of the patients ranged from 56 to 68 years in the FS group and from 55 to 68 years in the RS group. The percentage of women included ranged from 46 to 73 percent undergoing FS and from 33 to 70 percent undergoing RS. The main diagnosis was degenerative spine disease. The number of screws implanted ranged from 22 to 584 for FS and 23 to 532 for RS. The robots used were the SpineAssist and Renaissance Guidance System (Mazor Robotics, Ltd) and the TiRobot® Orthopaedic Robotic System (Beijing Tinavi Medical Technologies Co., Ltd). Pedicle screw placement within the safety zone (Grades A and B on the Gertzbein and Robbins scale) ranged from 93 to 100 percent in FS and from 85 to 100 percent in RS (relative risk 1.0, 95% confidence interval [CI] 0.99–1.03; p = 0.36) (I2=75%; p = 0.0005). Regarding intervention time, the meta-analysis showed a mean difference (MD) of 15.2 minutes (95% CI 5.35–25.05; p = 0.002) (I2 = 0%; p = 0.39) in favor of FS. The MD in hospital stay was 0.36 days (95% CI -1.03–0.31; p = 0.30) (I2 = 62%; p = 0.07), which was not statistically significant. Contradictory results were found for fluoroscopy time, although RS was associated with a lower radiation dose than FS (p < 0.05). In relation to safety, studies only reported on rates of surgical revision, which ranged from 0 to 2 after FS and from 0 to 10 after RS. The risk or bias was unclear in most studies.

We found no conclusive results suggesting benefits for spinal fusion using RS compared with FS. Further research with adequate selection of patients, type of robot, and comparator is needed.