Clinical and Radiological Outcomes of C1–C2 Fixation: 3D-Printed Template vs. Free-Hand Technique

<b>Objectives:</b> The Goel-Harms technique provides rapid stabilization and high fusion rates for atlantoaxial instability but carries a risk of neurovascular injury during lateral mass and pedicle screw insertion. Recently, 3D printing has emerged as a cost-effective and increasingly accessible tool in various surgical fields. This study aimed to compare the clinical and radiological outcomes of C1-C2 fixation using a 3D-printed template versus the free-hand technique. <b>Methods:</b> This retrospective cohort study included patients who underwent C1-C2 fixation with the Goel-Harms technique at two tertiary neurosurgical centers between 2021 and 2023. Operative, radiological, and functional outcomes were reviewed in 21 patients who were operated using either a patient-specific 3D-printed template applied intraoperatively (Group 1; <i>n</i> = 10) or the free-hand technique (Group 2; <i>n</i> = 11). Postoperative screw accuracy was assessed using the Gertzbein-Robbins classification. <b>Results:</b> A total of 84 screws were placed (Group 1: 40; Group 2: 44). In Group 1, 38 of 40 screws (95%) were accurately placed, compared with 41 of 44 screws (93.1%) in Group 2. The mean fluoroscopy and operative times were significantly shorter in Group 1 than in Group 2 (21.90 ± 4.33 s vs. 27.09 ± 13.48 s, <i>p</i> = 0.012; 126.60 ± 28.70 min vs. 171.36 ± 40.44 min, <i>p</i> = 0.010, respectively). <b>Conclusions:</b> The 3D-printed template technique significantly reduced operative and fluoroscopy times compared with the free-hand technique. Three-dimensional printing offers a cost-effective alternative to conventional navigation systems by eliminating their time-consuming preoperative setup in the operating room.