Tests and Diagnosis
What Your Doctor Does First — History and Physical Examination
Sorting Into Three Categories
According to clinical practice guidelines from the American College of Physicians and the American Pain Society (Chou 2007), doctors first classify low back pain into three categories:
| Category | Proportion | Description |
|---|---|---|
| Non-specific low back pain | ~85% | Pain where no single structural cause can be identified |
| Radiculopathy / spinal stenosis | ~10% | Pain with numbness or pain radiating into the legs |
| Specific pathology | ~5% | Fracture, cancer, infection, cauda equina syndrome |
Most people fall into the "non-specific" category. This does not mean "no cause" — it means no single cause can be pinpointed. (See "Why Does Your Back Hurt?" for more detail.)
Understanding the Questions Your Doctor Asks
Each question your doctor asks has a specific purpose:
| Doctor's Question | What They're Assessing |
|---|---|
| "When does the pain occur?" | Mechanical pain (worse with movement) vs. inflammatory pain (present at rest) |
| "Do you have morning stiffness?" | Stiffness lasting more than 30 minutes suggests an inflammatory condition |
| "Do you have numbness or tingling in your legs?" | Whether a nerve is being compressed |
| "Do your legs feel heavy or weak when walking?" | A hallmark of spinal stenosis (neurogenic claudication — leg pain or weakness with walking that improves with rest) |
| "Any changes in bladder or bowel function?" | Screening for cauda equina syndrome — a medical emergency |