What "middle back" means here
The upper back (the thoracic spine) has 12 vertebrae, each carrying a pair of ribs. The middle back is its lower half, from the lower tips of the shoulder blades to the bottom of the ribs, with the back of the ribs on each side. The kidneys sit here, under the lower ribs at the back, which is where the NHS places kidney infection pain: "in the back, just under the ribs". The NHS has no separate middle back page; its back pain page asks you to see a GP for back pain at the top of the back, between the shoulders, rather than the lower back.
Sources 1, 2
Most middle back pain is the back's muscles and jointsEmerging evidence
Back pain often starts for no obvious reason, and staying in one position too long, lifting something awkwardly, a flare-up of an old problem and doing more than usual can all set it off, NHS inform says; the spine is strong, and serious disease or damage is rare. Pain in the thoracic spine is common: across 33 studies, between 3.5% and 34.8% of people had it over a year, more often children, teenagers and women, and it was linked with backpacks, other aches and psychological factors. The ranges are wide because the studies defined it differently.
Sources 3, 4, 2
The rib joints and the small joints of the spineEmerging evidence
Each rib meets the spine at small joints, and the vertebrae have small joints of their own. When the rib joints were injected in 8 healthy male volunteers, they caused a deep, dull ache over the joint itself; when the small spinal joints of the mid back were injected in 9 healthy volunteers, they caused local and referred pain, with the areas for different joints overlapping. In a US pain clinic study, 42% of people with long-term thoracic pain were relieved by numbing these spinal joints, though single test blocks gave false positives 55% of the time. So these joints are a plausible source of a sharp, one-sided ache beside the spine, but no examination can confirm them.
Sources 5, 6, 7
Posture and sittingMixed evidence
An umbrella review of 41 reviews found no consensus that spinal postures, sitting, bending or twisting cause back pain, though most of that research is about the lower back. Forward head posture went with neck pain in adults but not in teenagers, in 15 studies. NHS inform says your posture doesn't need to be perfect; move often so you don't stay in one position for long. In 3,420 Chinese school students, carrying a backpack on one shoulder and slumped sitting went with back pain, including over time, but a study like this can't show cause and effect. No study we read tested posture as a cause of middle back pain.
Sources 8, 9, 3, 10
A spinal fracture from osteoporosisStrong evidence
With weak bones, a cough or sneeze can cause the partial collapse of a bone in the spine, the NHS says. About 86,000 spinal fractures happen in the UK each year, and most never come to medical attention, the UK osteoporosis guideline says. In 13,562 Europeans aged 50 and over, wedge-shaped fractures clustered in the middle of the thoracic spine and where the mid and lower back meet. In a US population, 83% of diagnosed spinal fractures followed moderate or no trauma, and 3% came from disease in the bone. A spinal fracture heals in 6 to 12 weeks, in its new, compressed shape, the Royal Osteoporosis Society says.
Sources 11, 12, 13, 14, 15
Teenagers and young adultsEmerging evidence
A rounded upper back in a teenager is usually postural kyphosis, the most common type, the NHS says; in Scheuermann's kyphosis, the vertebrae grow wedge-shaped. Ankylosing spondylitis usually starts in teenagers or young adults, with back pain and morning stiffness of 30 minutes or more that eases through the day or with activity, and it can cause painful inflammation where tendons and ligaments join the bone, including at the ribs, NHS inform says.
Sources 16, 17, 18
The organs that can be felt in the middle of the backStrong evidence
Each has its own clues, and the warning signs above give the action for each:
- The heart: the NHS heart attack page lists chest pain that feels tight or squeezing, spreading to the arms, neck or jaw, with breathlessness. The British Heart Foundation also lists pain that spreads to either arm, the neck, jaw, upper back or stomach, and says women sometimes have the less well-known symptoms rather than chest pain.
- The aorta, the body's main artery: sudden chest or back pain that can feel like something being torn inside, or sudden, severe tummy or back pain.
- The lungs: sudden breathlessness with pain in the chest or upper back (a clot in the lungs), or sharp chest pain on breathing in, often worse when you cough (pleurisy), which can spread to the shoulders and back.
- The kidneys: pain in the lower back or side, or in the back just under the ribs, with a fever, burning when you pee or feeling sick (an infection); or waves of severe pain starting in the side or lower back and spreading to the groin (a stone).
- The gallbladder: pain under the right ribs or in the middle of the tummy for more than 30 minutes, which may spread to the side or shoulder blade.
- The pancreas: pain at the top of the tummy that can spread through to the back or below the left shoulder blade, often eased by leaning forward and worse lying flat or after eating.
Sources 19, 20, 21, 22, 23, 24, 25, 1, 26, 27, 28, 29, 30, 31
Shingles, pregnancy, cancer and discs
Less common causes, each with its own clues:
- Shingles: a tingling or painful patch of skin on one side, then a rash a few days later, usually on the chest and tummy.
- Pregnancy: back pain with pain in one or both sides under the ribs needs your GP or midwife urgently, and pain below the ribs with a severe headache, vision problems or sudden swelling needs urgent help (pre-eclampsia).
- Cancer: with cancer now or in the past, new back pain that is severe, getting worse, worse at night or worse when you strain needs urgent advice, the National Institute for Health and Care Excellence (NICE) says; in people aged 60 and over, NICE asks GPs to test for myeloma with persistent bone pain, particularly back pain.
- A disc: disc herniations in the mid back are uncommon compared with the neck and lower back, a surgical review says.
Sources 32, 33, 34, 35, 36, 37
Tests and scansStrong evidence
Most back problems don't need an X-ray or a magnetic resonance imaging (MRI) scan, NHS inform says. The UK osteoporosis guideline recommends checking for a spinal fracture in people aged 50 and over with sudden back pain and risk factors for osteoporosis, or with 4 cm or more of height loss, a curved upper back or long-term steroids. With cancer, suspected spread to the spine needs an MRI, within 24 hours when the spinal cord may be squeezed, NICE says. Kidney stones are diagnosed from the symptoms, with urine or blood tests and sometimes a computerised tomography (CT) scan. An international framework notes that most single warning signs have little evidence of how accurate they are: they prompt a check, not a diagnosis.
Sources 3, 12, 35, 26, 38
How it usually goesEmerging evidence
Back pain often improves on its own within a few weeks, the NHS says, and most new back problems improve within 6 weeks, with the biggest change in the first couple of weeks, NHS inform says. In a trial of 143 people with mid back pain, pain and disability improved over 12 months whatever the treatment, including a sham. A spinal fracture heals in 6 to 12 weeks. No one can promise a date.
Sources 2, 3, 39, 15