A comparison of the methods of distraction for stress examination of the acromioclavicular joint.
Acromioclavicular joint disruption is frequently evaluated with a radiographic examination of the joint under stress (weight bearing). Certain authors recommend suspending the weights from the arm, rather than being hand-held, to allow for total muscle relaxation. This study examines the relationship between the coracoclavicular distance measured and the method of distraction. 30 normal subjects participated in the study which used ultrasound (5 MHz linear array) to measure the coracoclavicular distance under four conditions (levels of traction): non-stressed, muscles relaxed; non-stressed, muscles tensed; stressed with 7.5 kg weight hand held; stressed with 7.5 kg weight suspended from the wrist. The data were subjected to a multifactor ANOVA. The level of traction was statistically significant (p < 0.001). The data were then subjected to a Bonferroni multiple comparisons procedure. This showed a difference between the non-stressed and stressed conditions, but there was no difference between the two methods of applying stress to the joint. It was concluded that, in normal subjects, the method of performing the weight bearing examination does not have a significant effect on the magnitude of the coracoclavicular distance.
Department of Diagnostic Radiography, University of Liverpool, UK.
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Sluming
D000173:Acromioclavicular Joint / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008297:Male; D009126:Muscle Relaxation; D013314:Stress, Mechanical; D014463:Ultrasonography; D014894:Weights and Measures