Where it hurts is a clue, not a diagnosisStrong evidence
The NHS toe pain page sorts the causes by what you notice: sudden pain, stiffness and hot, swollen or red skin around the toe joint points to gout; a painful, swollen or bruised toe that hurts to walk on to a sprain or a break; and it lists ingrown toenails, bunions, chilblains and Raynaud's too. NHS inform adds that foot problems can come from the back even when your back doesn't hurt, felt as pins and needles, or sharp, hot or burning pain.
So this guide says a spot points to a cause rather than proving it, and an examination decides.
Sources 1, 2
A stiff, painful joint: big toe arthritisStrong evidence
The American Academy of Orthopaedic Surgeons (AAOS) calls big toe arthritis (hallux rigidus) the most common arthritic condition in the foot, usually from 30 to 60: pain on top of the joint when walking, trouble pushing off, a bump and stiffness, linked to wear, old injuries, foot shape and genes. In a survey of adults aged 50 and over in four UK general practices, painful arthritis of the big toe joint on X-rays was estimated in 7.8%, more in women and with age.
Arthritis UK says the big toe is the foot joint most commonly affected by osteoarthritis, and a review says a turf toe that was never recognised can lead to a stiff, arthritic joint later.
Sources 3, 4, 5, 6
A lump on the side: a bunionStrong evidence
Across 76 surveys of almost half a million people, bunions (hallux valgus) affected 23% of adults aged 18 to 65 and 36% of over-65s, 30% of women and 13% of men. The NHS describes a hard lump on the side of the foot by the big toe, the toe pointing towards the others, and pain worse in shoes and when walking, and says badly fitting shoes may make bunions more likely (a page past its review date). The AAOS says the pain comes from shoe pressure over the bump.
Sources 7, 8, 9
Sudden, hot, red and swollen: goutStrong evidence
Gout affects about 2.5% of the UK population, more men and older people, and the big toe joint is where it most often strikes; an attack peaks within 12 to 24 hours and settles in 1 to 2 weeks, a UK review says, and only a minority of people with a high urate level get gout. The National Institute for Health and Care Excellence (NICE) suspects gout with rapid onset, often overnight, of severe pain with redness and swelling in one or both big toe joints.
Arthritis UK says about three-quarters of the urate in your body comes from purines your body makes itself, and only about a quarter from food and drink, and inherited ways the kidneys handle urate are a common cause. The NHS lists family history, being a man, excess weight, alcohol, the menopause, some medicines, high blood pressure, kidney problems and diabetes, and triggers such as alcohol, a large meal, dehydration and an injury (a page past its review date).
Sources 10, 11, 12, 13
Under the joint: the sesamoids, and turf toeStrong evidence
Two small bones under the big toe joint, the sesamoids, act as pulleys for the tendons that bend the toe. The AAOS says sesamoiditis builds up gradually under the ball of the foot and is common in ballet dancers, runners and baseball catchers, while a sesamoid can break with sudden pain after the toe is forced back, or from repeated stress.
Turf toe is a sprain of the big toe joint when it is forced upwards with the heel off the ground, graded 1 to 3 by how badly the tissue under the joint is torn. A review says it is relatively rare and easily missed.
Sources 14, 15, 6
The nail, the cold and the skinStrong evidence
An ingrown toenail usually affects the big toe: red, painful, swollen skin at the side of the nail as it curves in, and pus if it becomes infected, the NHS says; the AAOS says tight shoes and cutting the nail too short are the usual causes. Chilblains are itchy or burning, red or purple patches on the toes a few hours after being cold, and they usually clear in 2 to 3 weeks.
Sources 16, 17, 18, 1
Diabetes, nerves and the circulationStrong evidence
Diabetes UK says raised blood sugar can damage the small blood vessels and nerves in the feet, so you may not feel an injury and wounds can heal slowly, and a minor problem such as a blister can quickly become a serious infection or ulcer. NICE asks for an active diabetic foot problem to reach a specialist foot service within 1 working day, and suspects a Charcot foot, where the foot's joints break down, with redness, warmth, swelling or a change of shape even without pain.
Peripheral neuropathy, nerve damage that usually starts in the feet, causes numbness, tingling or burning (an NHS page past its review date), and the NHS asks people with diabetes to see a GP or diabetes nurse about blisters or cracked skin on their feet. Psoriatic arthritis can cause a swollen toe (an NHS page past its review date).
Sources 19, 20, 21, 22, 23
When a scan or test helpsStrong evidence
Big toe arthritis is diagnosed from an examination and X-rays, which show the spurs and the narrowed joint. Gout is diagnosed from the story and the examination and confirmed by a blood urate level of 360 micromol per litre or more, repeated at least 2 weeks after the flare if it was lower; a typical big toe attack can be recognised clinically, and fluid from the joint or a scan helps if it's still unclear. In a hot, red, swollen joint, an infection has to be ruled out first.
Turf toe needs X-rays to rule out a small break or a sesamoid out of place, with a magnetic resonance imaging (MRI) scan for the worse grades. A sesamoid problem gets X-rays first, sometimes of both feet because in some people a sesamoid is normally in two parts, then a bone scan or MRI if the X-ray is normal. A broken toe often needs no X-ray, but a suspected broken big toe goes to A&E.
Sources 3, 12, 10, 11, 24, 15, 14, 25, 26
How it usually goesEmerging evidence
An untreated gout attack usually lasts 1 to 2 weeks, and untreated gout can come back more often and damage the joint. Most broken toes heal in 4 to 6 weeks, sometimes several months. A mild turf toe often allows play in a stiff-soled shoe, a moderate one usually needs 3 to 14 days' rest and a severe one weeks of protection. Sesamoid problems can take weeks or months, though most settle without surgery. Chilblains usually clear in 2 to 3 weeks.
Big toe arthritis and bunions are long-term: shoes and exercise ease the pain, and surgery is the option when pain still limits your walking. No one can promise a date.
Sources 11, 25, 15, 14, 18, 3, 8