gms | German Medical Science

Objective: Neuronavigation for pedicle screw placement in dorsal instrumentation is routinely performed in multiple centers. Neuronavigation for lateral instrumentation is also an upcoming approach. With this in mind, we started to perform navigated dorsal and lateral instrumentation of the lumbar spine in a single operation and positioning.

Methods: Patients with 1- or 2-level discitis scheduled for dorsal and lateral instrumentation were prospectively enrolled and the surgeons’ evaluations were acquired. Intraoperatively, we positioned patients semi-prone in a 45 degree fashion to enable both dorsal pedicle screw placement and lateral interbody fusion (LLIF). For spinal navigation, a registration array was attached to the pelvis or spinal process and intraoperative computed tomography (ioCT) scans were acquired for registration and control of screw and cage positioning.

Results: Up to now, we included 10 patients suffering from 1- or 2-level discitis. The mean±standard deviation body-mass index was 28.5±6.0 with a median (range) ASA score of 2.5 (1-3). Overall, we placed 46 pedicle screws with an intraoperative revision rate of 13.1%, primarily based on a navigation error during one single surgery leading to revision of 4 screws. LLIF was performed on 13 levels with an intraoperative revision in 1 patient (7.7%). The mean duration of surgery was 127.4±42.0 min with a mean blood loss of 410±354 ml. No patient showed intra- or postoperative complications. For surgeons, the new positioning and orientation for instrumentation was feasible, positively rated with an overall median of 9 (range 3-10; [scale min-max 1-10]) and a median mental load of 20 (range 0-100; [scale max-min 150-0]). A learning curve was measurable by the decrease of mental load.

Conclusion: Navigated dorsal and lateral instrumentation of the lumbar spine in a single operation and positioning is feasible and safe. It enables to accelerate 360° instrumentation of patients and shows high acceptance and learning curves even in a high-volume spine center. Compared to the prone LLIF technique, anatomical orientation and physical burden seem to be advantageous at least in a subjective manner.