Robert Lambert | PubMed Health

PubMed2006

A pilot study of magnetic resonance imaging-guided closed reduction of cervical spine fractures.

STUDY DESIGN: We report on a prospective selective case series of 17 patients with cervical fracture-dislocations treated with closed reduction under MRI guidance. OBJECTIVE: To demonstrate the safe and effective use of in-line axial traction in the reduction of cervical fracture-dislocations using MRI guidance. SUMMARY OF BACKGROUND DATA: Closed reduction of the cervical spine for acute fracture-dislocations has been a traditional technique used for restoring vertebral alignment and providing neural element decompression. The safety of this technique has been questioned, with concerns of disc migration and overdistraction causing neurologic worsening cited as reasons to choose operative reduction and decompression as a safer option in some circumstances. METHODS: Seventeen patients with fracture-dislocations of the subaxial cervical spine were given a trial of traction under MRI guidance between 1999 and 2003. The incidence of posteriorly herniated disc material was noted, and the diameter of the spinal canal at the injured level was recorded before and after traction. RESULTS: All patients tolerated traction without neurologic worsening. Pretraction disc disruption was found in 15 of 17 (88.2%) of patients, with posterior herniation in 4 of 17 (23.5\%). Traction caused a return of herniated disc material toward the disc space in all cases. Canal dimensions improved in 11 of 17 patients, with canal diameter increasing by a factor of 1.1 to 3.0, with a mean improvement of 1.73. The process of reduction was observed to be a gradual one, with progressive, significant improvement in canal dimensions occurring before anatomic realignment. As distracting force was increased, sequential MRIs showed that canal dimensions did not diminish at any time in any patient. CONCLUSIONS: MRI monitoring in closed cervical reduction is a useful research tool for this technique. Closed reduction appears to be safe as used in this preliminary study and is effective in achieving immediate spinal cord decompression.

Adult↗

PubMed2005

Evaluating MRI as a technique for visualizing the neurocentral junction.

STUDY DESIGN: Magnetic resonance imaging (MRI) of the neurocentral junction (NCJ) was correlated with gross anatomic and histologic sections acquired at the same position. OBJECTIVES: To determine the composition of the MRI of the NCJ and to explore the long-standing discrepancy between the ages of closure of the NCJ as determined by anatomic and imaging studies. SUMMARY OF BACKGROUND DATA: Disparate growth at the site of the NCJ has been implicated as a potential cause of adolescent idiopathic scoliosis since the early 1900s. Although anatomic studies have refuted this theory by maintaining that the NCJ closes before the age of 10 years, recent MRI studies have suggested that the NCJ remains open until adolescence. METHODS: One hundred fourteen porcine NCJs in various stages of development were visualized using MRI. Gross anatomic and histologic sections were acquired at the same position as MRI for correlation. RESULTS: The presence or absence of NCJ cartilage was represented by the presence or absence of a line on MRI. However, the NCJ image overestimated the width of the NCJ cartilage in the anteroposterior direction during development. As the NCJ underwent the process of closure, the NCJ image underestimated the extent of closure in the medial-lateral direction. CONCLUSIONS: Although MRI underestimated the extent of NCJ closure, MRI accurately showed whether cartilage was present or absent at the NCJ site. MRI determination of the age of NCJ closure appears reliable, and further exploration of the asymmetric growth hypothesis is required.

Aging↗