Neurodynamics are used to assess mechanosensativity of neural tissues. They can be effected by the position of the nervous system in relation to a joints axis of movement, the health of the surrounding structures, and adverse tension (ie. multiple entrapment or compression sites of the nervous system affecting the overall mobility of and ability to transmit tension in the nervous system). There has been some debate regarding the origin of symptoms (neural vs. non-neural) elicited due to the amount of structures stressed during these tests. Both the slump and SLR also provoke pain in presence of a lumbar disc herniation due to traction of the inovlved nerve root.
Slump: The patient is seated with the back straight and looking straight ahead. The patient is then asked to “slump”, fully flex the neck and then extend one knee while dorsiflexing the same foot. Reproduction of symptoms is a + test and sciatic nerve tension. Sensativity:83%, Specificity: 84% (values for indicating lumbar root compression due to disc herniation).
- SLR Test
SLR: The patient lays supine. Keeping the knee fully extended, the examiner flexes the patient hip until reaching full flexion or until the patient experiences discomfort. The angle of hip flexion is then measured. A SLR test stretches the L5&S1 nerve roots 2mm-4mm so when positive, indiciates a lesion of L5/S1. This will occur during the first 70 degrees of flexion. Past 70 degrees of flexion, tension is placed on the sciatic outside of the spinal canal. Sensativity: 52% Specificity: 89% (values for indicating lumbar root compression due to disc herniation).
Upper Limb Tension Tests:
Median Nerve Bias
Ulnar Nerve Bias
Radial Nerve Bias