Ninety-degree rotation of the thoracic spinal thecal sac. Case report

A case of adult α-type spinal deformity with spinal cord rotation greater than 90°

This report describes a 42-year-old man who presented with an α-type spinal deformity with a Cobb angle of 224.9° and associated spinal cord rotation greater than 90°. Preoperative imaging revealed extensive spinal deformity, and 3D modeling confirmed the α-type nature of his deformity. Intraoperative photography demonstrated spinal cord rotation greater than 90°, which likely contributed to the patient's poor neurological status. Reports of patients with Cobb angles ≥ 100° are rare, and to the authors' knowledge, there have been no published cases of adult α-type spinal deformity. Furthermore, very few cases or case series of spinal cord rotation have been published previously, with no single patient having rotation greater than 90° to the authors' knowledge. Given these two rarities presenting in the same patient, this report can provide important insights into the operative management of this difficult form of spinal deformity.

Assessing the rotation of the spinal cord in idiopathic scoliosis: a preliminary report of MRI feasibility

PURPOSE

Magnetic resonance imaging (MRI) quantification of the rotation of the spinal cord in patients with thoracic idiopathic scoliosis could also be used to detect different spinal cord rotational patterns.

METHODS

Ten patients with a thoracic or thoracolumbar scoliosis had axial T2-weighted MRI. The rotation of the spinal cord and vertebra were measured. The rotational data of the spinal cord and vertebra was compared to other collated data using non-parametric tests.

RESULTS

The vertebral tile was measured from 3 degrees to 32 degrees and the spinal cord tilt was measured from 3 degrees to 39 degrees. The spinal cord tilt was statistically correlated with the Cobb angle and the antero-posterior or and transverse diameter of the spinal cord.

CONCLUSION

We showed that, even in case of moderate curve with very limited angular values and vertebral rotation, a significant spinal cord rotation occurred. However, our findings are very limited to discuss some hypothesis about scoliosis pathogeny or progression mechanism.