Is there a way to diagnose spinal instability in acute burst fractures by performing ultrasound?

Abstract

The aim of this study is to examine the predictive value of ultrasound diagnostics for the assessment of traumatic lesions of the posterior ligament complex (PLC) in burst fractures of the thoracolumbar spine. This was a prospective validating cohort study. Judgment about instability and treatment of burst fractures depends on the condition of the PLC. There have been some studies describing underdiagnosis of PLC injuries due to classification problems in ligamentary distraction type fractures. The gold standard for assessing these lesions is magnetic resonance imaging (MRI). Even then, there are often limits in contemporary operational availability and technical limitations of MRI. Ultrasound was described being an alternative. In a prospective study, 54 levels of 18 patients with acute burst fractures of the thoracic and lumbar spine have been examined by ultrasound and additional MRI scans preoperatively. The condition (intact vs. ruptured) of supraspinous ligament (SSL) and the interspinous ligament has been assessed for the ligaments separately. Hematoma below the SSL has also been evaluated as an indirect sign of an injured PLC. In all the patients the primary performed operative treatment was a posterior spinal instrumentation. Postoperatively the blinded results of the ultrasound procedures have been matched against intraoperative and MRI findings. Assessments of all target structures have been contributed to the calculation of the sensitivity and specificity of ultrasound. A total of 18 patients, 14 males and 4 females, with acute burst fractures have been qualified for inclusion in the study. The patients' mean age was 43.4 years. Comparing intraoperative findings with preoperatively performed investigations, ultrasound archived a sensitivity of 0.99 and a specificity of 0.75 (P < 0.05) to detect traumatic lesions to the PLC. As hypothesized the obtained predictive value using ultrasound correlates closely with intraoperative findings. Anyway MRI still seems to be the superior diagnostic method for examining the PLC. However, ultrasound can be considered to be an adequate alternative method in cases with contraindications for MRI such as ferromagnetic side effects, claustrophobia, availability or emergency diagnostics in multiple injuries.

The precision, accuracy and validity of detecting posterior ligamentous complex injuries of the thoracic and lumbar spine: a critical appraisal of the literature

“…This resulted in a total number of 21 included articles of this review. Eight studies evaluated the agreement on PLC injury evaluation [15][16][17][18][19][20][21][22], another eight studies evaluated the accuracy of detecting PLC injuries [23][24][25][26][27][28][29][30] and one study evaluated both agreement and accuracy [31]. Four studies reported on different validity components of PLC injuries [32][33][34][35].…”

“…Two studies documented blinding of both test and reference observers. Except for the study by Vordemvenne et al [30], none of the accuracy studies provided details about the experience of the observers. …”

“…The accuracy of detecting facet joint capsule disruptions and thoracolumbar fascia injuries was evaluated by Vaccaro et al [24] and found to be relatively low (69-79 %). Vordemvenne et al [30] found low predictive values for detecting a hematoma below the supraspinous ligament (see Table 6). …”

“…Six studies evaluated the accuracy of detecting PLC injury as a broad entity and six studies evaluated the accuracy of detecting injuries of specific PLC structures. Using ultrasound diagnostics, Vordemvenne et al [30] also evaluated the presence of a hematoma below the SSL, which was considered as an indirect sign of PLC injury.…”

“…Two studies evaluated the accuracy of detecting an injury of the PLC as a broad entity on MR imaging [30,31]. Although detailed accuracy data were not presented, the PPVs and NPVs were high ([93 %).…”