Martin Docherty

Flexion-extension views in the evaluation of cervical-spine injuries

STUDY OBJECTIVE To determine the efficacy of flexion-extension (F/E) cervical-spine radiographs in detecting acute cervical-spine instability in emergency patients. DESIGN We retrospectively reviewed the charts of 141 consecutive trauma patients who had F/E views performed after a routine cervical-spine series (three views) was obtained in the emergency department. Interpretations of the routine series were compared with those of the F/E views to determine if additional useful information was provided by the latter. The charts also were reviewed to determine if any variables were associated with an increased use of F/E views, an increased likelihood of these views demonstrating instability, or any neurologic sequelae resulted from these studies. SETTING An urban Level I adult trauma center. MEASUREMENTS The interpretations of the routine series were noted to be either normal, abnormal but without demonstrable fracture/dislocation, or demonstrating a fracture/dislocation. The F/E views were categorized as stable, unstable, or uninterpretable. RESULTS Cervical-spine instability was demonstrated by F/E views in 11 of the 141 patients (8%), four of whom had normal routine cervical-spine films. Three of these four patients required surgical stabilization. Prolonged neck pain (more than 24 hours), an initially abnormal spine series, and a neurosurgical consult were all associated with an increased use of F/E views. Ten of 11 patients with radiographic instability had significant neck pain by history; the remaining patient was intoxicated. No neurologic sequelae resulted from performing F/E studies. There was one false-negative F/E study, which raises concern about the reliability of this procedure in the ED. CONCLUSION We believe that a large prospective study is required to determine which patients warrant F/E views.

Urine dipstick testing to rule out rhabdomyolysis in patients with suspected heat injury

BACKGROUND Heat injury is a common, potentially life-threatening medical condition. In austere or mass-casualty conditions an easy to use, sensitive screening test could be a valuable tool to care providers and evacuation planners. OBJECTIVE The objective of the study was to determine if a simple urine dipstick test for blood is sensitive for detection of rhabdomyolysis in the suspected heat injury patient. MATERIAL AND METHODS A convenience sample of patients presenting to a military community hospital Emergency Department during summer months with a presenting complaint consistent with suspected heat injury had urine dipstick testing performed for blood and compared with the results of formal urinalysis and serum creatine kinase. RESULTS 60 patients were enrolled in the study, seven had creatine kinase levels greater than 1000 U/L, 14 had levels greater than 500 U/L, and 26 had levels greater than 250 U/L. Using 1000 U/L, urine dipstick testing had a sensitivity of 14% and a specificity of 85%. CONCLUSIONS Urine dipstick testing for blood is not a useful screening test for rhabdomyolysis in patients suspected to have significant heat injury.

Can Elbow Extension Be Used as a Test of Clinically Significant Injury

Background. The objective of this study was to evaluate whether a simple test of full elbow extension was a reliable indicator of bone/joint injury at the elbow joint. Methods. In this prospective study, patients with acute elbow injuries were asked to fully extend the injured elbow. Radiologists blinded to the results of the extension test interpreted the radiographs. Results. Of 114 patients with acute elbow injury entered into the study, 110 underwent radiographic evaluation. Inability to extend the elbow was found in 37 of 38 patients with bone injury. Only 1 of 54 patients who were able to fully extend the elbow was found to have bone/joint injury. The sensitivity and specificity of the elbow-extension test for identification of bone/joint injury was 97% and 69%, respectively. Conclusions. The elbow-extension test can be used as a sensitive clinical screening test for patients with acute elbow injuries.

U1 small nuclear RNA-like sequences in human high molecular weight RNA.

Human U1 small nuclear RNA synthesis was shown earlier to be very sensitive to UV radiation. This led us to test for the possible presence of U1 RNA-like sequences in large RNAs. Human RNA was analyzed in gel blots hybridized with U1 DNA probes. A high molecular weight, heterodisperse RNA population was detected, which hybridizes both to a U1 RNA-coding region single-stranded DNA probe, and to a U1 gene fragment that contains only 6 nucleotides of flanking sequence. These large RNAs can be hybrid selected using immobilized U1 DNA, and have an average size of several kilobases. Additional observations support the claims that the high molecular weight RNA hybridization signal is not an aggregation artifact and that it is sequence specific.