The prone hip extension test: a method of measuring hip flexion deformity.

The "prone hip extension test" is described as a simple, convenient, and reliable method of measuring hip flexion contracture. The test may be performed on a padded examining table or bed, it is applicable to the spastic patient, and as the patient is examined prone, it provides a method of flattening the lumbar spine under visual control to avoid obtaining either a falsely high or low value. It, therefore, circumvents the problems commonly associated with the traditional "Thomas Test".