A new stress test for the diagnosis of hip dysplasia: a preliminary study on a manikin

Early detection of hip dysplasia remains elusive due to lack of a safe and objective diagnostic screening test. A new hip stress test sequence for improving the diagnosis of hip dysplasia is proposed: firstly the Barlow manoeuvre is performed, followed by an instrumented hip stiffness test and lastly the Ortolani test. Both the Barlow and the Ortolani tests consist of manual manipulative examinations which produce characteristic vibration in abnormal hips. The clinical examiner detects this vibration using finger-tip sensation. T o verify this three-phase technique, the test was performed on a commercially available patient simulator. The force applied to the hip joint was measured using a force plate, and the hip laxity measured with an instrumented linkage. Significant differences in hip stiffness were found between dislocated and reduced hips. Further clinical testing will allow the theory to be finally verified and the technique to be refined.