Preoperative Planning With Patient-Specific 3D-Printed Anatomical Models in Non-Traumatic Spinal Deformity Surgery: Systematic Review.

BackgroundPatient-specific three-dimensional (3D)-printed anatomical models are increasingly used for preoperative planning in spinal deformity surgery. Their potential to improve intraoperative efficiency is clinically attractive, but the available evidence remains limited. To assess whether preoperative planning assisted by patient-specific 3D-printed anatomical models improves surgical outcomes in patients undergoing surgery for non-traumatic spinal deformities and malformations, compared with conventional planning.MethodsA systematic review was conducted according to PRISMA 2020. Comparative studies evaluating patient-specific 3D-printed anatomical models for preoperative planning in pediatric or adult patients with non-traumatic spinal deformities were included. Studies primarily focused on intraoperative 3D-printed pedicle screw guides were excluded. Data on operative time, intraoperative blood loss, fluoroscopy time, and postoperative complications were extracted. Risk of bias was assessed using ROBINS-I.ResultsSix single-center comparative studies involving 344 patients were included. Operative time was reported in four studies; two showed significant reductions favoring 3D model-assisted planning, including 184.3 vs 212.3 min and 375 vs 456 min. Intraoperative blood loss was also reported in four studies; two found significantly lower blood loss in the intervention group, including 846.7 vs 1029.7 mL and 363 vs 442 mL. Postoperative complications were generally less frequent in intervention groups. Most studies were judged at serious risk of bias, and one at critical risk.ConclusionsPreoperative planning using patient-specific 3D-printed anatomical models may improve operative time and blood loss in non-traumatic spinal deformity surgery; however, the evidence remains methodologically weak, and long-term functional outcomes have not been evaluated.