There was no correlation between bony displacement and transverse ligament integrity. CT scans post-injury may not show the position of maximal displacement. If there is clinical concern about a possible transverse ligament injury, MRI should be performed.

A 44-year-old man presented after 3 weeks of progressively worsening atraumatic onset pain in the right anteromedial thigh. The pain was sharp and radiated to the anteromedial shin and medial foot. The patient had no associated weakness, numbness, or bowel/bladder dysfunction. Nonsteroidal anti-inflammatory, pain, and neuropathic-relieving drugs had limited effect. He underwent interlaminar injections, which provided transient relief of his shin symptoms. After conservative management failed, a spine surgeon (not affiliated with our practice) recommended an anterior lumbar interbody fusion via far lateral approach. The patient presented to our spine clinic for a second opinion. Closed magnetic resonance imaging revealed an aberrant iliac artery impinging on the lumbar plexus and a foraminal herniation at L4-L5 on the right, an orientation more lateral than expected or seen on the contralateral side. We recommended physical therapy that focused on core strength and adequate stretching prior to considering surgery. The patient's symptoms have since resolved. Common iliac artery anomalies are rare. No known incidence exists. The finding in this case was incidental and, if missed, could have led to vascular compromise. To prevent such an injury during minimally invasive (transpsoas lateral approach) spine surgery, we recommend careful examination of radiographs for aberrant vessels.

Specific characteristics of the postoperative MRI can be used to distinguish infection from noninfectious fluid collections. The strongest predictors of infection were osseous involvement and destructive bony changes. Hematoma was associated with mass effect on the thecal sac, high T1-signal intensity, and absence of thecal sac communication and disk involvement. CSF collections were distinguished by absence of mass effect, low T2-signal complexity, low T1-signal intensity, and communication with the thecal sac.