Can vibration-induced illusions be used as a muscle perception test for normal and cerebral-palsied children?

Since poor control of muscle contractions in cerebral palsy may be due partly to defective processing of data originating from muscle, the need arose for a test as uncontaminated as possible by other afferent effects. For 18 normal children, vibration of the brachial biceps tendon always gave the illusion of elbow extension; when the triceps was vibrated the opposite illusion occurred. For 22 cerebral-palsied children the vibration test was successful for 26 elbows and failed for 18. These failures might provide a future explanation for certain therapeutic failures.