Late diagnosis of perforation of the aorta by a pedicle screw.

Although the clinical and biomechanical advantages of pedicle screws are well documented, the accuracy of their insertion is always a concern.Injury of neurovascular structures could be devastating. Perforation of the aorta from posteriorly placed screws is fortunately rare but could end up being lethal. We present a review of the current literature along with two illustrative cases with aorta perforation from posterior pedicle screws. An 82-year-old female with a history of thoracic kyphosis and a 26-year-old female with scoliotic deformity were referred to our institution owing to back pain. Both patients had undergone correction of their deformities and posterior fixation using posterior pedicle screws and rods 5 years previously. During the diagnostic work-up, which included CT scans, we incidentally found one pedicle screw to be malpositioned, exiting the vertebral body and perforating the aorta. The patients were offered a combined orthopaedic and vascular procedure, including screw removal and endovascular stenting of the aorta. Potential complications from the presence of a screw inside the pulsatile aorta, and the complexity of revision surgery should be well considered before proceeding to such a difficult surgical procedure. Systemic postoperative follow-up imaging and safer intraoperative practices during screw placement are important.

Insidious Onset of Tetraparesis due to Cervical Epidural Abscess from Enterococcus faecalis.

We report a case of cervical epidural abscess from Enterococcus faecalis, which caused an insidious onset of tetraparesis. This 53-year-old female with a history of diabetes mellitus and chronic renal failure under hemodialysis presented with pain and progressive weakness of upper and lower extremities without fever. Although a recent MRI she did at the beginning of symptoms showed no significant pathologies, except for a cervical disc herniation and adjacent spinal degeneration, and stenosis that confused the diagnostic procedure, newer imaging with CT and MRI, which was performed due to progression of tetraparesis, revealed the formation of a cervical epidural abscess. Surgical drainage was done after a complete infection workup. The patient showed immediate neurological improvement after surgery. She received antibiotics intravenously for 3 weeks and orally for another 6 weeks. The patient was free from complications 24 months after surgery. A high index of suspicion is most important in making a rapid and correct diagnosis of spinal epidural abscess. The classic clinical triad (fever, local pain, and neurologic deficits) is not sensitive enough for early detection. Continuous clinical, laboratory, and imaging monitoring are of paramount importance. Early diagnosis and surgical intervention could optimize the final functional outcome.