A radiological measure of shoulder subluxation in hemiplegia: its reliability and validity

Arch Phys Med Rehabil. 1993 Feb;74(2):188-93.


This study describes the reliability and validity of a new radiological method to measure shoulder subluxation that is based on taking a single x-ray of the affected shoulder in the plane of the scapula. A digitizer and a computer are used to quantify the measurements directly from the x-ray. One single radiological view of the shoulder taken in a standardized position provides four measures of subluxation including a measure of vertical subluxation, horizontal subluxation, a normalized distance sensitive to both vertical and horizontal subluxation, and an angular measure. A total of 72 volunteers with cerebrovascular accidents participated in the study. Thirty-six subjects had a clinical shoulder subluxation and 36 had no clinical subluxation. The construct validity analysis showed significant differences (p < .001) between the mean scores for subluxed and nonsubluxed groups on all four measures of subluxation. The concurrent validity of the x-ray measures in relation to external clinical measures (finger's breadth, measures in centimeters with calipers or a plexiglass jig) was moderate. Three measures were found to be reliable and valid whereas the fourth, a measure of horizontal subluxation has lower reliability. However, it does have clinical significance. The clinical and research implications of this study are presented.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Analysis of Variance
  • Diagnosis, Computer-Assisted
  • Diagnosis, Differential
  • Evaluation Studies as Topic
  • Female
  • Hemiplegia / complications*
  • Humans
  • Male
  • Middle Aged
  • Observer Variation
  • Posture
  • Radiography / instrumentation
  • Radiography / methods
  • Radiography / standards*
  • Reproducibility of Results
  • Scapula / diagnostic imaging*
  • Sensitivity and Specificity
  • Shoulder Dislocation / diagnostic imaging*
  • Shoulder Dislocation / epidemiology
  • Shoulder Dislocation / etiology
  • Signal Processing, Computer-Assisted