Low Back Pain Causes: What 6 Health Sources List, and Their 3-Day to 6-Week Marks for Seeing a Doctor

Low back pain often starts with a strain.

The health sources below name the usual causes. They also set the point to see someone at anywhere from 3 days to 6 weeks, and sooner when certain symptoms show up.

This page summarizes public health and hospital sources. It is not medical advice.

See a doctor instead of waiting it out if low back pain comes with fever, trouble controlling your bladder or bowels, or weakness in your legs. Stanford Medicine lists these three as signs of a possibly serious problem. UC Davis Health names fever and bladder or bowel trouble among its reasons to see a doctor.

8 in 10 people get back pain at some point

MedlinePlus, the NIH’s consumer health site, says back pain affects 8 out of 10 people at some point in their lives. UC Davis Health counts it as one of the most frequent reasons people see a doctor. Brown University Health calls lower back pain “the most common cause of job-related disability.”

So the real questions are what caused yours and how long to give it. Each source answers part of that.

Muscle, tendon or ligament strain is the cause the lists share

Cleveland Clinic says lower back pain often results from a strain to the muscles or tendons in your back, and it defines a strain as an injury. The other hospital pages name the same thing in their own words. Brown University Health lists muscle sprain or strain, and Stanford Medicine lists muscle or ligament strain. Ligaments are the tough bands that hold bone to bone, and they also come up on the UC Davis Health and MedlinePlus encyclopedia pages.

When the problem is in this soft tissue, Brown says the pain can come from inflamed tissue, tears or muscle spasms. In plain words, the tissue that moves and steadies your spine is irritated, torn or clenched.

Arthritis and disk problems are on Cleveland Clinic, Brown and Stanford’s lists

Besides strain, Cleveland Clinic names arthritis, structural problems and disk injuries. Brown lists a herniated disc and arthritis. Stanford lists bulging or slipped discs and arthritis. That makes arthritis and disk trouble the two non-strain causes all three hospital pages name.

NIAMS (the National Institute of Arthritis and Musculoskeletal and Skin Diseases) adds two points. First, inflammatory arthritis disorders or other medical conditions sometimes cause back pain. Second, several factors often feed into it at once, so your pain may not trace back to one neat cause.

The timeline: sources say see someone at 3 days, 2–4 weeks or 6 weeks

The MedlinePlus encyclopedia says acute back pain can last a few days to a few weeks. Here is every time mark in these sources, in order, so you can see where you are.

When	What the source says	Source
After an injury, at any point	Get medical attention for back pain that follows an injury	MedlinePlus
3 days	Call your provider if the pain is severe or has not improved	MedlinePlus
2 to 4 weeks	See a doctor if the pain lasts longer than this	UC Davis Health
Several weeks	See a doctor if home care has not helped	Brown University Health
4 to 6 weeks	The window in which most people recover	MedlinePlus encyclopedia
4 to 12 weeks	Back pain is called “subacute”	NIAMS
6 weeks	Pain lasting longer is the point for a specialist referral	Brown University Health
Over 3 months	Back pain is called “chronic”	MedlinePlus

Spread of the “see someone” marks = 3 days (MedlinePlus) to 6 weeks x 7 days = 42 days (Brown University Health); 42 / 3 = 14, so the latest mark is 14 times the earliest.

Three things the table shows that no single page does:

1. The marks ask different questions. MedlinePlus’s three days is about pain that is severe or not getting better. UC Davis’s 2–4 weeks and Brown’s several weeks are about pain that simply has not gone away.
2. Three sources meet at 4 to 6 weeks. NIAMS’s “subacute” label starts at 4 weeks, exactly where UC Davis’s mark ends. Brown’s six-week referral line falls at the far end of the encyclopedia’s 4-to-6-week recovery window.
3. “Chronic” is a label, not a deadline to wait for. Every “see someone” mark comes well before MedlinePlus’s three-month line.

Eight signs to see a doctor instead of waiting

If any of these fits, the timeline above stops applying: skip the waiting and see a clinician. Stanford lists the first three as signs that, with low back pain, can point to a serious problem. UC Davis lists fever, bladder or bowel trouble and the rest as reasons to see a doctor.

1. Fever (Stanford, UC Davis)
2. Trouble controlling your bladder or bowels (Stanford, UC Davis)
3. Weakness in your legs (Stanford); UC Davis lists weakness too
4. Numbness or tingling (UC Davis)
5. Pain that spreads down one or both legs (UC Davis)
6. A recent injury or fall (UC Davis)
7. Weight loss you cannot explain (UC Davis)
8. Past cancer or HIV therapy (UC Davis)

First steps: keep moving, use ice or heat, and limit bed rest to 1–2 days

If none of the signs above fits, these are the home steps the sources give:

1. Stay active. UC Davis’s advice is to “stay active and avoid long bed rest.” MedlinePlus says more than 1 or 2 days in bed can make back pain worse.
2. Rest, but don’t stop moving entirely. Brown recommends rest “but not complete inactivity.”
3. Ice first, then heat. After an injury, Brown suggests ice for the first two days and heat after that. UC Davis lists both heating pads and ice packs.
4. Stretch gently. UC Davis includes gentle stretching.
5. Avoid heavy lifting and twisting at first, per UC Davis.

All three sources make the same point. Rest is fine, but lying still for days is not, which is why Brown and UC Davis pair rest with movement.

The only gear these pages name for the first days is a heating pad or an ice pack. Neither replaces a visit if you have a warning sign.

When to see a clinician: use the earliest mark that fits you

This map has limits. The sources’ time marks run from three days to six weeks instead of one agreed number, and no web page can assess your back. Read together, though, they agree on the order: warning signs and injuries first, then pain that is severe or not improving, then pain that lasts more than a few weeks.

So use the earliest mark that applies to you. Skip self-care and see a clinician now if any of the eight signs fits, or if the pain began with an injury or fall. Otherwise, start with the first steps above and check yourself against the table, starting from the top row.