The Relation between Cord Signal and Clinical Outcome after Anterior Cervical Discectomy in Patients with Degenerative Cervical Disc Herniation

New Imaging Modalities for Degenerative Cervical Myelopathy

INTRODUCTION

Degenerative cervical myelopathy (DCM) is defined as dysfunction of the spinal cord as a result of compression from degenerative changes to surrounding joints, intervertebral disks, or ligaments. Symptoms can include upper extremity numbness and diminished dexterity, difficulty with fine manipulation of objects, gait imbalance, and incoordination, and compromised bowel and bladder function. Accurate diagnosis and evaluation of the degree of impairment due to degenerative cervical myelopathy remain a challenging clinical endeavor requiring a thorough and accurate history, physical examination, and assessment of imaging findings.

METHODS

A narrative review is presented summarizing the current landscape of imaging modalities utilized in DCM diagnostics and the future direction of research for spinal cord imaging.

RESULTS AND DISCUSSION

Current imaging modalities, particularly magnetic resonance imaging and, to a lesser extent, radiographs/CT, offer important information to aid in decision making but are not ideal as stand-alone tools. Newer imaging modalities currently being studied in the literature include diffusion tensor imaging, MR spectroscopy, functional magnetic resonance imaging, perfusion imaging, and positron emission tomography. These newer imaging modalities attempt to more accurately evaluate the physical structure, intrinsic connectivity, biochemical and metabolic function, and perfusion of the spinal cord in DCM. Although there are still substantial limitations to implementation, future clinical practice will likely be revolutionized by these new imaging modalities to diagnose, localize, surgically plan and manage, and follow patients with DCM.

Outcome of Surgery for Congenital Craniovertebral Junction Anomalies with Atlantoaxial Dislocation/Basilar Invagination: A Retrospective Study of 94 Patients

OBJECTIVE

To evaluate the results of surgery for congenital craniovertebral junction (CVJ) anomalies with atlantoaxial dislocation (AAD)/basilar invagination (BI) and compare the results of transoral odontoidectomy and posterior fusion (TOO+PF) with only posterior fusion (PF) in patients with irreducible AAD/BI.

METHODS AND RESULTS

All 94 patients with congenital CVJ anomalies with AAD/BI operated on during the 3-year study period (June 2013-May 2016) were included. Of these patients, 55 had irreducible AAD/BI and the remaining 39 had reducible AAD/BI. TOO+PF was restricted to patients (34/94; 36.2%) with irreducible AAD/BI when reduction and realignment by intraoperative C1-C2 facet joint manipulation were considered technically difficult and risky. The remaining patients with irreducible AAD/BI and all the patients with reducible AAD/BI (60/94; 63.8%) were managed with only posterior fusion. Poor preoperative Nurick grade, preoperative dyspnea/lower cranial nerve deficits, and syringomyelia were associated with significantly higher incidence of postoperative pulmonary complications. Follow-up ≥3 months (final follow-up) was available for 87 patients. Good outcome (Nurick grade 0-3) at final follow-up was noted in 90% (45/50) of the patients with irreducible AAD/BI and 91.9% (34/37) of the patients with reducible AAD/BI. Preoperative poor Nurick grade (4-5) was the only factor associated with poor outcome. No significant difference in perioperative complications, outcome, and fusion was noted between patients who underwent TOO+PF or only PF for irreducible AAD/BI.

CONCLUSIONS

Many of the patients with congenital AAD/BI showed remarkable recovery after surgery. Preoperative poor Nurick grade (4-5) is associated with poor outcome. TOO+PF is a safe alternative treatment option for irreducible AAD/BI when only PF techniques are technically difficult/risky.