Torsion of left main bronchus during general anesthesia for posterior instrumented spinal fusion.

Pulmonary function tests such as flow-volume loops and reconstructive radiological imaging may aid the detection of large airway obstruction prior to corrective surgery for severe scoliosis. Intraoperative use of halo-gravity traction may help to reduce the severity of the scoliosis, and thus the extrinsic compression or torsion of the airways.

Detecting Facet Joint and Lateral Mass Injuries of the Subaxial Cervical Spine in Major Trauma Patients.

STUDY DESIGN: Radiologic imaging measurement study. PURPOSE: To assess the accuracy of detecting lateral mass and facet joint injuries of the subaxial cervical spine on plain radiographs using computed tomography (CT) scan images as a reference standard; and the integrity of morphological landmarks of the lateral mass and facet joints of the subaxial cervical spine. OVERVIEW OF LITERATURE: Injuries of lateral mass and facet joints potentially lead to an unstable subaxial cervical spine and concomitant neurological sequelae. However, no study has evaluated the accuracy of detecting specific facet joint injuries. METHODS: Eight spinal surgeons scored four sets of the same, randomly re-ordered, 30 cases with and without facet joint injuries of the subaxial cervical spine. Two surveys included conventional plain radiographs series (test) and another two surveys included CT scan images (reference). Facet joint injury characteristics were assessed for accuracy and reliability. Raw agreement, Fleiss kappa, Cohen's kappa and intraclass correlation coefficient statistics were used for reliability analysis. Majority rules were used for accuracy analysis. RESULTS: Of the 21 facet joint injuries discerned on CT scan images, 10 were detected in both plain radiograph surveys (sensitivity, 0.48; 95% confidence interval [CI], 0.26-0.70). There were no false positive facet joint injuries in either of the first two X-ray surveys (specificity, 1.0; 95% CI, 0.63-1.0). Five of the 11 cases with missed injuries had an injury below the lowest visible articulating level on radiographs. CT scan images resulted in superior inter- and intra-rater agreement values for assessing morphologic injury characteristics of facet joint injuries. CONCLUSIONS: Plain radiographs are not accurate, nor reliable for the assessment of facet joint injuries of the subaxial cervical spine. CT scans offer reliable diagnostic information required for the detection and treatment planning of facet joint injuries.

The Subaxial Cervical Spine Injury Classification System: an external agreement validation study.

BACKGROUND CONTEXT: In 2007, the Subaxial Cervical Spine Injury Classification (SLIC) system was introduced demonstrating moderate reliability in an internal validation study. PURPOSE: To assess the agreement on the SLIC system using clinical data from a spinal trauma population and whether the SLIC treatment algorithm outcome improved agreement on treatment decisions among surgeons. STUDY DESIGN: An external classification validation study. PATIENT SAMPLE: Twelve spinal surgeons (five consultants and seven fellows) assessed 51 randomly selected cases. OUTCOME MEASURES: Raw agreement, Fleiss kappa, and intraclass correlation coefficient statistics were used for reliability analysis. Majority rules and latent class modeling were used for accuracy analysis. METHODS: Fifty-one randomly selected cases with significant injuries of the cervical spine from a prospective consecutive series of trauma patients were assessed using the SLIC system. Neurologic details, plain radiographs, and computed tomography scans were available for all cases as well as magnetic resonance imaging in 21 cases (41%). No funds were received in support of this study. The authors have no conflict of interest in the subject of this article. RESULTS: The inter-rater agreement on the most severely affected level of injury was strong (κ=0.76). The agreement on the morphologic injury characteristics was poor (κ=0.29) and agreement on the integrity of the discoligamentous complex was average (κ=0.46). The inter-rater agreement on the treatment verdict after the total SLIC injury severity score was slightly lower than the surgeons' agreement on personal treatment preference (κ=0.55 vs. κ=0.63). Latent class analysis was not converging and did not present accurate estimations of the true classification categories. Based on these findings, no second survey for testing intrarater agreement was performed. CONCLUSIONS: We found poor agreement on the morphologic injury characteristics of the SLIC system, and its treatment algorithm showed no improved agreement on treatment decisions among surgeons. The authors discuss that the reproducibility of the SLIC system is likely to improve when unambiguous true morphologic injury characteristics are being implemented.

Is fixation failure after plate fixation of the symphysis pubis clinically important?

BACKGROUND: Plate fixation is a recognized treatment for pelvic ring injuries involving disruption of the pubic symphysis. Although fixation failure is well known, it is unclear whether early or late fixation failure is clinically important. QUESTIONS/PURPOSES: We therefore determined (1) the incidence and mode of failure of anterior plate fixation for traumatic pubic symphysis disruption; (2) whether failure of fixation was associated with the types of pelvic ring injury or pelvic fixation used; (3) the complications, including the requirement for reoperation or hardware removal; and (4) whether radiographic followup of greater than 1 year alters subsequent management. METHODS: We retrospectively reviewed 148 of 178 (83%) patients with traumatic symphysis pubis diastasis treated by plate fixation between 1994 and 2008. Routine radiographic review, pelvic fracture classification, method of fixation, incidence of fixation failure, timing and mode of failure, and the complications were recorded after a minimum followup of 12 months (mean, 45 months; range, 1-14 years). RESULTS: Hardware breakage occurred in 63 patients (43%), of which 61 were asymptomatic. Breakage was not related to type of plate, fracture classification, or posterior pelvic fixation. Five patients (3%) required revision surgery for failure of fixation or symptomatic instability of the symphysis pubis, and seven patients (5%) had removal of hardware for other reasons, including late deep infection in three (2%). Routine radiographic screening as part of annual followup after 1 year did not alter management. CONCLUSIONS: Our observations suggest the high rate of late fixation failure after plate fixation of the symphysis pubis is not clinically important.