Comparison of Transoral Anterior Jefferson-Fracture Reduction Plate and Posterior Screw-Rod Fixation in C1-Ring Osteosynthesis for Unstable Atlas Fractures

Abstract

Objective: To compare the clinical outcomes of transoral anterior Jefferson-fracture reduction plate (JeRP) and posterior screw rod (PSR) surgery for unstable atlas fractures via C1-ring osteosynthesis.

Methods: From June 2009 to June 2022, 49 consecutive patients with unstable atlas fractures were treated by transoral anterior JeRP fixation (JeRP group) or PSR fixation (PSR group) and followed up at General Hospital of Southern Theatre Command of PLA; 30 males and 19 females were included. The visual analogue scale (VAS) score, Neck Disability Index (NDI), distance to anterior arch fracture (DAAF), distance to posterior arch fracture (DPAF), lateral mass displacement (LMD), Redlund-Johnell value, postoperative complications, and fracture healing rate were retrospectively collected and statistically analyzed.

Results: Compared with that in the PSR group, the bleeding volume in the JeRP group was lower, and the length of hospital stay was longer. The VAS scores and NDIs of both groups were significantly improved after surgery. The postoperative DAAF and DPAF were significantly smaller after surgery in both groups. Compared with the significantly shorter DPAF in the PSR group, the JeRP group had a smaller DAAF, shorter LMDs and larger Redlund-Johnell value postoperatively and at the final follow-up. The fracture healing rate at 3 months after surgery was significantly greater in the JeRP group (p < 0.05).

Conclusion: Both C1-ring osteosynthesis procedures for treating unstable atlas fractures yield satisfactory clinical outcomes. Transoral anterior JeRP fixation is more effective than PSR fixation for holistic fracture reduction and short-term fracture healing, but the hospital stay is longer.

Keywords: Atlas fracture; C1-ring osteosynthesis; Posterior approach; Transoral anterior approach; Unstable fractures.

Fig. 1.

Schematic of the Jefferson-fracture reduction plate (JeRP) procedure. (A, B) Coronal and axial pictures present the reducing process: after the compressing reduction forceps was installed, one arm hooked the reduction hole of the JeRP and the other arm clasped the reduction screw and then closed the handle of the forceps to achieve fracture end closure. (C, D) Coronal and axial pictures present the fixation: after the fracture was satisfactorily reduced, the remaining anterior arch screws and lateral mass screws on the other side were fixed.

Fig. 2.

A 50-year-old female with combined fractures of the anterior and posterior atlantoaxial arches was treated by transoral anterior C1-ring osteosynthesis using the Jefferson-fracture reduction plate (JeRP). (A) Preoperative open-mouth x-ray imaging showed displacement of the lateral masses. (B, C) The axial images of computed tomography (CT) scan and 3-dimensional reconstruction revealed fractures of the anterior and posterior arches with displacement of the lateral mass. (D) Preoperative magnetic resonance imaging showed no spinal cord compression. Red arrows showed the fracture breaks. (E, F) Postoperative open-mouth and lateral x-ray imaging identified the well C1–2 alignment. (G, H) Postoperative CT images revealed reduction of the fracture and adequate placement of the JeRP. (I, J) Open-mouth and lateral x-ray images at 6 months after surgery showed no loosening of the plate or screws. (K, L) CT images at 6 months after surgery revealed solid bone fusion.

Fig. 3.

Schematic of the posterior screw rod procedure. (A, B) Coronal and axial pictures present the reducing process: after C1 pedicle screws were inserted, a suitable length of connecting rod was selected and placed horizontally into both screw slots. Then, nuts were put into both sides, and only one side was tightened. The fracture was repositioned by lateral compression with a pair of reduction forceps. (C, D) Coronal and axial pictures present the fixation: after the fracture was satisfactorily reduced, locked the nut on the other side.

Fig. 4.

A 61-year-old male with combined fractures of the anterior and posterior atlantoaxial arches was treated by posterior C1-ring osteosynthesis using the posterior screw rod. (A) Preoperative open-mouth x-ray imaging showed displacement of the lateral masses. (B, C) The axial images of computed tomography (CT) scan and 3-dimensional reconstruction revealed fractures of the anterior and posterior arches of the atlas with displacement of the lateral mass. (D) Preoperative magnetic resonance imaging showed no spinal cord compression. Red arrows showed the fracture breaks. (E, F) Postoperative open-mouth and lateral x-ray imaging showed good C1–2 alignment with adequate placement of PSR. (G, H) Postoperative CT image after surgery revealed reduction of fracture. (I, J) Open-mouth and lateral x-ray images at 9 months after surgery showed no loosening of the rob and screws. (K, L) CT images at 9 months after surgery revealed solid bone fusion.

Fig. 5.

Schematic diagram of measurement indicators in computed tomography (CT) scan. (A) Axial CT image shows the distance of anterior arch fracture equals “a”; the distance of posterior arch fracture equals “b”. (B) Coronal CT image shows the lateral mass displacement equals “c1+c2”. (C) Sagittal CT image shows the Redlund-Johnell value equals “d”.