Intra-articular Distraction Versus Decompression to Treat Basilar Invagination Without Atlantoaxial Dislocation: A Retrospective Cohort Study of 54 Patients

Neurospine, 2023 · DOI: https://doi.org/10.14245/ns.2244910.455 · Published: June 30, 2023

Simple Explanation

Basilar invagination is a condition where the top of the spine pushes into the skull, potentially compressing the brainstem and spinal cord. Type B basilar invagination occurs without a specific dislocation of the upper neck bones. This study compares two surgical approaches for treating this condition: foramen magnum decompression (FMD), which creates more space around the brainstem, and a newer technique involving distraction and fixation of the C1-C2 facet joints. The study found that the C1-C2 distraction and fixation technique resulted in better reduction of the basilar invagination, more nerve relief, and improved clinical outcomes compared to FMD.

Study Duration

March 2017 and December 2021

Participants

54 patients with type B basilar invagination

Evidence Level

Retrospective cohort study

Key Findings

1
Patients undergoing intra-articular distraction, fixation, and cantilever reduction experienced better reduction of basilar invagination and nerve decompression.
2
The experimental group (intra-articular distraction) showed statistically significant improvements in JOA and SF-12 scores compared to the control group (FMD).
3
SF-12 score improvement was associated with preoperative CVJ triangle area, with a cutoff value of 2.00 cm2 indicating the surgical indication of the intra-articular distraction technique.

Research Summary

This retrospective study compared intra-articular C1–2 facet distraction, fixation, and cantilever reduction with foramen magnum decompression (FMD) for treating type B basilar invagination. The intra-articular distraction technique resulted in better radiographic reduction of basilar invagination, improved nerve decompression, and superior clinical outcomes compared to FMD. The study suggests that posterior intra-articular C1–2 facet distraction, fixation, and cantilever reduction is an effective treatment for type B basilar invagination, particularly when the CVJ triangle area is >2.00 cm2.

Practical Implications

Surgical Technique Choice

For type B basilar invagination, posterior intra-articular C1-2 facet distraction, fixation, and cantilever reduction may be a more effective surgical option compared to foramen magnum decompression, especially in patients with a CVJ triangle area >2.00 cm2.

Preoperative Assessment

Preoperative assessment should include measurement of the CVJ triangle area to determine the suitability of the intra-articular distraction technique.

Clinical Outcomes

Patients undergoing intra-articular distraction can expect greater improvements in clinical outcomes (JOA and SF-12 scores) compared to those undergoing foramen magnum decompression.

Study Limitations

1
Retrospective study design
2
Single-center study
3
Surgical method decisions were based on patients' willingness, which may import inherent biases.

Your Feedback

Was this summary helpful?

Back to Surgery