Lower Back Pain

  I'm a 45 year old female (not overweight) in good health.
  From time to time,I experience back pain in the very low spine area.  
  The pain seems to extend about two inches on the left and right side
  of the spine.  Aspirin usually helps as well as lying on one or two  
  tennis balls (a trick I remember from childbirth).  Sitting for long
  periods of time sometimes seems to initiate the pain.  Also, the pain
  seems to be getting worse and lasting for longer periods of time (2 - 3
  days).  Any ideas?
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Dear Martin:
Suggest a careful exam by your primary physician, and a few physical therapy sessions to learn back muscle strengthening exercises (extension) if your MD thinks it is okay. Occasional use of ASA, ibuprofen/naproxen as needed. Improvement of posture and change of habits (e.g. not bending down to pick up something heavy).