Sciatic Notch

Expose the sciatic nerve dorsally adjacent to the femur and follow it proximally to the sciatic notch where it disappears under the pelvis. 

In contractile experiments the time from the stimulation of the nerve to the CMAP recorded in muscle provides an estimate of NCV. The length of the nerve from the stimulating electrode to the muscle can simply be measured and divided by the time. However, the time recorded in this way includes the delay for synaptic transmission, which may be increased in models with synaptic defects. If this is a concern or if the only parameter desired is NCV, then the measurement can be obtained non-invasively with a relatively simple setup (e.g., (3)). Using the sciatic nerve, NCV can be calculated by measuring the latency of compound motor action potentials recorded in the muscle of a rear paw. Action potentials are produced by subcutaneous stimulation at two separate sites proximal stimulation at the sciatic notch and distally at the ankle. NCV is then calculated by using the two latencies and conduction distance. Decreases in nerve conduction velocity most often reflect defects in myelination, but may also be the result of changes in internodal distance, decreased axon diameters, or altered excitability. 

On examination, the left buttocks was lender to palpation and there were tender points at the mid-pole of the sacrum on the lateral border and one deep to the gluteus maximus, where a lense piriformis could be palpated. There was a unilateral sacral flexion (sacral shear) present on the left. No lumbar somatic dysfunctions were present. There was mild tenderness at the sciatic notch of the ischium. Deep tendon reflexes were normal and muscle strength of the ihigh was normal. There was some pain on internal rotation and adduction of the left hip. 

Distally to the sciatic notch, most sciatic nerve lesions arise from significant trauma, such as fracture dislo-... 

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