Lower Back Pain

Today in morning report we talked about lower back pain.

Here are some pearls from the discussion:

1) Red flags are reasons to do more advanced imaging (ie. CT or MRI). They are also clues that you may be dealing with something like infection or malignancy. These include:
- age over 60
- night pain ("can't find a comfortable spot in bed")
- fever, other constitutional symptoms
- history of malignancy
- IVDU
- bowel and bladder incontinence

2) Neurological exam for radiculopathy- in Dr Carette's word "it's all in the feet".
A patient with back pain may be limited by pain in terms of what they are willing to do at the hip and knee. The neurological assessment of the foot can be very high yield, with some useful tricks as follows:

- Motor testing: to test L5 only, test extensor hallucis longus with resisted big toe extension. Test S1 with resisted toe curling.

- Sensory: test sensation of medial aspect of shin (L4), in web between big toe and D2 (L5) and on lateral foot and sole (S1)

- Reflexes: Patellar (L2-4) and Ankle jerk (S1).

Note if you want to test L5, can check for the hamstring reflex  as follows: The patient should be lying in the supine position with the knee and hip partially flexed and the leg supported by the examiner's hand. Then, using your reflex hammer, tap one of the medial hamstring tendons behind the knee, causing contraction of the tendon and flexion of the knee.

Follow this link to great review of low back pain from NEJM