Measurement of spinal sagittal configuration and mobility with Debrunner's kyphometer.

A considerable number of instruments have been described for noninvasive measurements of the sagittal configuration and mobility of the thoracolumbar spine. With Debrunner's kyphometer, it is possible to obtain this information in approximately 1 minute in a clinical setting. A minor modification of the kyphometer to increase its range of measurement of lumbar extension is described. Repeatability of measurements with the instrument was studied on 31 healthy individuals in a randomized cross-over model. In another study, ten individuals were examined ten times each by the same investigator within 3 weeks. These studies showed good reproducibility for measurements with the kyphometer. The importance of standardized instructions for measurement procedures is emphasized. The statistical approach to repeatability of measurements is discussed.