The Forgotten Femoral Nerve!
Reference:Trainor K, et al Reliability and diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression: a pilot study. Physiotherapy. 2011 Mar;97(1):59-64.
The sciatic nerve neurodynamic test (NDT) also known as the SLR test is well known by us but, I want to share with you the less known and less frequently practiced femoral nerve NDT. I realize that compared to the sciatic nerve (L5-S1), femoral nerve (L2-4) issues are relatively uncommon, but surely they should not be forgotten about.
On your next patient who reports of back and anterior thigh pain or quad weakness or difficulty climbing steps, apply the concepts from the following two studies.
The femoral nerve NDT has been shown to have good inter-tester reliability and validity for diagnosing L2-4 nerve root compression.
(To see a short video of this test please go to Youtube and search “APTEI”)
For identifying patients with mid lumbar (L2-L4) nerve root compression, when compared to an MRI, the femoral nerve NDT test had 100% sensitivity and 83% specificity.
Translation: If the femoral n. NDT test is -ve you can confidently rule out L2-4 nerve root compression, however if the femoral n. NDT is +ve, L2-4 nerve root compression (or at least an irritation) is likely present.
Important Note: Of course you can never look at just one test …for diagnosing any condition you must have a composite of clinical findings.
For the diagnosis of L2-4 nerve root impingement, the combination of a +ve femoral nerve NDT, reduced patellar reflex testing and +ve single leg sit to stand test had a positive likelihood ratio of >7, which is really good!
Posted on: July 05, 2012
Categories: Lumbar Spine