Back pain affects roughly 619 million people worldwide, making it the single leading cause of disability on the planet. Most of the time, the cause is mechanical: something in the muscles, ligaments, or structures of the spine is strained, compressed, or irritated. But back pain can also come from organs that have nothing to do with your spine, and psychological factors like stress can make it significantly worse. Understanding what’s behind your pain helps you figure out what to do about it.
Muscle Strains and Ligament Sprains
The most common reason your back hurts is a strain or sprain. A strain happens when the muscles or tendons supporting your spine get twisted, pulled, or torn. A sprain is the same thing, but in a ligament, the bands of tissue that connect bones at a joint. Both can happen from a single awkward lift, a sudden twist, or a fall. They can also develop slowly from repetitive movement over weeks or months.
Several things raise your risk. Weak core and back muscles leave your spine without adequate support. Tight hamstrings pull on your pelvis and change how your lower back absorbs force. Carrying excess weight puts constant extra load on the spine. Sports that involve pushing and pulling, like weightlifting and football, also increase the chance of injury. Even something as simple as curving your lower back too far during everyday activities can set the stage for a strain.
The good news: most back pain from strains and sprains resolves in about one to two weeks.
Disc Problems
Between each vertebra in your spine sits a rubbery disc with a tough outer shell and a soft, gel-like center. When that outer shell tears or weakens, the inner material can push outward or leak through entirely. This is called a herniated disc (sometimes referred to as a bulging, slipped, or ruptured disc), and it causes pain primarily by pressing on nearby spinal nerves.
A herniated disc in the lower back commonly triggers sciatica, a sharp pain that shoots from your buttock down one leg, sometimes all the way to your foot. You might also feel tingling or numbness in your legs or feet. Disc herniations can result from injury, but they often happen from the gradual wear and tear of daily life, especially as you get older and the discs lose water content and become less flexible.
Spinal Stenosis and Aging
As the spine ages, the channel that houses your spinal cord can narrow. This condition, called spinal stenosis, develops when bone spurs grow or discs bulge inward, reducing the space available for nerves. Most people with spinal stenosis are over 50.
The hallmark symptom is pain or cramping in one or both legs when you stand for a long time or walk. The pain typically improves when you bend forward or sit down, because leaning forward opens up the spinal canal slightly and takes pressure off the nerves. This pattern, where walking hurts but sitting or leaning on a shopping cart feels better, is one of the clearest signals that stenosis is involved.
Inflammatory Back Pain
Not all back pain comes from wear, tear, or injury. Some types are driven by inflammation from your immune system. Ankylosing spondylitis is one example. It typically causes lower back and hip pain along with pronounced stiffness, and it behaves differently from most mechanical back pain in a key way: it gets worse with rest and better with movement.
If your back pain is worst in the middle of the night or after prolonged sitting, and exercise actually helps, that pattern suggests an inflammatory cause rather than a structural one. Ankylosing spondylitis can also produce symptoms far from the spine, including eye inflammation, skin rashes, rib pain that makes it hard to take deep breaths, and fatigue. Over time, the condition can cause vertebrae to fuse together, leading to a rigid spine. It tends to start in younger adults, unlike most degenerative back conditions.
Pain That Isn’t Coming From Your Spine
Your back can hurt even when nothing is wrong with your back. Kidney stones are a classic example. When a stone gets stuck in the tube connecting your kidney to your bladder, it blocks urine flow and causes the kidney to swell. The result is serious, sharp pain in the side and back below the ribs that can spread to the lower abdomen and groin. The pain often shifts location and intensity as the stone moves.
The key difference from spinal pain: kidney stone pain doesn’t change with position. Bending, sitting, standing, or lying down won’t make it better or worse. It also tends to come in waves rather than being constant, and it’s frequently accompanied by nausea, blood in the urine, or a persistent urge to urinate. Other organs that can refer pain to the back include the pancreas, the aorta (the body’s main artery), and, in women, the uterus during conditions like endometriosis.
How Stress Makes Back Pain Worse
Psychological distress doesn’t just accompany back pain. It actively amplifies it. When you’re stressed or anxious about your pain, your body releases hormones and activates neural pathways designed for self-protection. These responses increase muscle tension and lower your pain threshold, making the same physical problem feel significantly worse over time and increasing the disability it causes.
A pattern called pain catastrophizing is one of the strongest psychological predictors of whether acute back pain becomes chronic. It involves three components: ruminating on the pain (“I can’t stop thinking about how much it hurts”), magnifying the threat (“something serious must be wrong”), and feeling helpless (“this is overwhelming and I can’t handle it”). People with high levels of catastrophizing and low confidence in their ability to manage pain are at considerably greater risk for long-term back problems. This doesn’t mean the pain is imaginary. It means that your mental state is a real, measurable factor in how your nervous system processes pain signals.
What Actually Helps
For back pain that’s lasted days to a few weeks, clinical guidelines from the American College of Physicians recommend starting with non-drug approaches: applying heat, getting a massage, trying acupuncture, or seeing a provider for spinal manipulation. If you want medication, over-the-counter anti-inflammatory drugs like ibuprofen are the first choice.
For chronic back pain lasting three months or more, the recommended first step is still non-drug therapy, but the menu expands considerably. Exercise is at the top of the list. Yoga, tai chi, cognitive behavioral therapy, mindfulness-based stress reduction, and progressive relaxation all have evidence supporting their use. The emphasis on psychological approaches makes sense given how powerfully stress and catastrophizing influence chronic pain. Medications become an option if these strategies aren’t enough on their own.
The overall trajectory for most people is reassuring. The majority of back pain episodes clear up within a week or two without any specific treatment. Staying gently active rather than resting in bed tends to speed recovery.
Signs That Need Immediate Attention
A small number of back pain cases involve nerve compression serious enough to cause permanent damage if not treated quickly. Cauda equina syndrome, where the bundle of nerves at the base of the spine gets compressed, is the most urgent. Symptoms include lower back pain combined with numbness in the inner thighs, buttocks, or groin area, difficulty urinating or having bowel movements, leg weakness, or new incontinence. This combination requires an emergency room visit. The back pain alone isn’t the red flag. It’s the combination of pain with bladder, bowel, or progressive neurological symptoms that signals a time-sensitive problem.