Is Direct Transpedicular C2 Fixation (Judet Approach) a Timeless Technique to Learn for C2 Fractures?

Dear Editor,

Recently, we read with great interest the article “Biomechanical Evaluation of a C1-C2 Posterior Arch Screw Construct”, Fernandes et al, ¹ in which the authors compare the biomechanics of a C1-C2 posterior arch and translaminar screw construct against the Harms technique for posterior atlantoaxial fixation on a human cadaveric model, demonstrating that a C1-C2 posterior arch screw construct restores or increases biomechanical stability compared to the intact condition, as well C1-C2 posterior arch screw offers similar biomechanical stability compared to the Harms construct.

Otherwise not too many months ago, Zou et al ² published “Transoral Atlantoaxial Reduction Plate (TARP) Technique for the Treatment of Irreducible Atlantoaxial Dislocation (IAAD) Caused by Old Odontoid Fracture”, in which the authors reported their experience in the treatment of IAAD with a TARP technique, which can provide immediate reduction, fixation and fusion after release for C2 fractures through a single transoral approach without the need for a posterior operation. The transoral approach at the craniocervical junction is also used to treat rheumatoid pannus, tumors with spinal cord compression and basilar invagination.^3,4 Although Zou et al ² reported that all patients achieved satisfactory reduction and fixation with clinical symptomatic relief in all cases (100%) without injury to the spinal cord, nerves or blood vessels, this is a challenging technique, requiring good surgical and spinal anatomy skills and a learning curve.

Similarly, the direct transpedicular C2 fixation, commonly known as the Judet approach, for the surgical management of Hangman fractures is technically challenging. The Judet approach has been introduced in 1970 as a surgical option to treat selected cases of hangman’s fractures, harboring the advantage to preserve motion of the craniovertebral junction and to restore the C2 vertebra anatomy by insertion of transpedicular screws through the fracture line. ⁵

In a postgraduate training program for spinal surgeons, we ask ourselves if it is still important to learn the Judet technique, given the recent opportunity for different approaches with a lower incidence of complications. Learning transpedicular screw fixation for C2 fractures remains essential in spinal surgery. This technique offers several advantages, including the preservation of craniovertebral junction motion and the restoration of C2 vertebral anatomy by inserting screws through the fracture line. In addition, the application of this technique in selected patients should be considered to achieve early mobilization and avoid external fixation.

In 2023, Certo et al ⁵ highlighted that the Judet approach is gaining appeal, with no consensus on surgical indications. The study reported 2 cases of Hangman’s fractures treated with direct transpedicular C2 screw fixation, noting significant reduction of neck pain postoperatively and preservation of craniovertebral junction motion at follow-ups. ⁵

Furthermore, in 2020, Liu et al ⁶ introduced a new transpedicular lag screw fixation technique for unstable Hangman’s fractures, reporting satisfactory clinical and radiographic results. This approach was noted for its simplicity, effectiveness, reliability and cost-effectiveness. ⁶

The atlantoaxial region has a high risk of screw placement due to its special structure and proximity to the high spinal cord and vertebral artery. The incidence of vertebral artery injury during C2 transpedicular screw placement is usually <0.5% per screw, with approximately 2% per patient undergoing C1–C2 fusion. ⁷ To avoid possible complications such as neurovascular injury, infection, cerebrospinal fluid leak, pharyngeal foreign body sensation, swallowing difficulty, screw misplacement, the use of neuronavigation to enhance the precision of C2 pedicle screw placement and reduce the risk of neurological and vascular complications. ⁸ Lee et al. ⁹ demonstrated that O-arm navigation slightly improved the accuracy rate of C2 pedicle screw placement, compared to the freehand technique, although no statistically significant results were reported, whereas Hlubek et al ¹⁰ in 2018 wrote that freehand technique was significantly more accurate than CT-based navigation for C2 pars/pedicle screw placement.

Judet approach allows for more accurate identification of anatomical landmarks, ensuring safer and effective fixation in bilateral and/or unilateral C2 pedicle fractures in particular in Hangman’s fractures, as also in complex C2 fractures (combination with odontoid process fracture). ⁸ Neuronavigation is highly valuable in this context as it enhances the surgeon’s ability to precisely identify both the anatomical landmarks and the entry point and to guide screw trajectory. ¹¹ Additionally, the use of spinal neuronavigation is also useful in helping less experienced surgeons accurately place screws, identify anatomical landmarks and improve their learning curve in the treatment of C2 cervical fractures.^4,8 Minimally invasive/mini-open neuronavigation-guided posterior C2 transpedicular fixation, as well as TARP technique, are safe and effective techniques used to manage C2 instability.

The use of 3D simulators or augmented reality that led to increased surgical manual skills in cervical surgery should be considered.^11,12 Similarly, technological advances in the form of 3D-printed implants, high-resolution MRI, 3D CT scans, and AI-based analytics have aided in early diagnosis and surgical planning. Although transpedicular screw fixation of C2, as well posterior arch screw and TARP technique, are not commonly used in everyday surgical practice, their knowledge and use in the operating room should be considered in selected cases. For all these reasons, learning all these techniques remains essential in the armamentarium of a spine surgeon.