Spinal deformity is a common reason for spinal surgery at youth. In addition, the incidence of surgery for spinal deformity in older adults is increasing. Spinal deformity surgery is by far the most complex spine surgery. One complexity lies in the correct placement of implants in the severely deformed spine. Today, the most common surgical procedures for spinal deformity involve placement of screws in the vertebral pedicle in the instrumented part of the spine. This gives good bone purchase, which is important for deformity correction.~The pedicle is narrow and misplaced pedicle screws can result in vascular, pulmonary or neural injuries, or inadequate bone purchase. Compared to the conventional free-hand surgical technique, which relies on the knowledge of anatomy, computer-assisted navigation using intraoperative 3D imaging has been shown to improve screw placement accuracy and reduce complications due to screw misplacements. As a consequence, navigation may also reduce the frequency of postoperative revision surgery compared to free hand. However, navigation still takes time, and is associated with higher intraoperative radiation than the free hand technique.~As of yet, the majority of data in this area are based on retrospectively collected series, and some prospectively collected series, while randomized controlled trials on spinal deformity are lacking.~In this randomized controlled trial the accuracy of pedicle screw placement using augmented reality surgical navigation (ARSN), infra-red surgical navigation (IRSN) and conventional free-hand technique will be investigated.~Patients of age 12 years and older with spinal deformities are randomized into one of the three surgical techniques mentioned above.~The primary outcome variable is pedicle screw placement accuracy at 1st attempt assessed using the Gertzbein scale.
The spinal navigation trial (SPINAV) is a randomized controlled trial (RCT) evaluating the use of computer-assisted navigation in surgery for spinal deformity