Osteoporosis

In osteoporosis, bone loses density and internal scaffolding: from the outside it looks the same, but inside it comes to resemble a sponge with large holes. Such a bone breaks under a load a healthy one would take — a fall from standing height, an awkward movement, sometimes a hard bout of coughing. Osteoporosis itself does not hurt and gives no signal for years, so most people first hear of it in an emergency department. It is not an inevitable part of getting older: there are medicines that clearly cut the risk of fracture.

Why bone loses its strength

Bone is living tissue that renews itself throughout life: some cells clear away old material while others build new. Until roughly the age of thirty, building runs ahead, and a person reaches their peak strength. After that the balance tips towards breakdown, and a small yearly loss is normal.

Osteoporosis begins where breakdown outpaces building for a long time. In women this is most often tied to the menopause: oestrogen holds back the cells that dismantle bone, and once the ovaries stop producing it the loss speeds up sharply, most of all in the first few years. The earlier the menopause arrives, the longer that period of loss.

Men get osteoporosis too, and it is no gentler in them: on average they cope worse with a hip fracture. Here low testosterone, steroid tablets, alcohol and chronic illness carry more weight, and in about half of cases no cause is found.

How osteoporosis shows itself

The first sign is usually a fracture after a minor injury. The typical sites are the wrist after falling onto an outstretched hand, the hip and the vertebrae, along with ribs, shoulder and pelvis. The rule is simple: a fracture caused by a fall from standing height or by even less force is a reason to have your bones assessed, not merely bad luck.

Spinal fractures are the most deceptive of all: most of them pass without dramatic pain and turn up by chance. Indirect signs can raise the suspicion:

• height has dropped by four centimetres or more compared with your younger years;
• the upper back has rounded, the head sits forward, and it is hard to touch the back of your head to a wall;
• the ribs have started to meet the pelvis, the abdomen sticks out and clothes sit differently;
• there is constant back pain and you tire quickly when standing;
• breathing feels cramped and you feel full very quickly, because the chest and abdomen have lost height.

What osteoporosis does not do: it does not cause diffuse aching in bones and joints and does not explain pain all over. If the bones "ache" everywhere, the cause lies elsewhere.

When not to wait

Call an ambulance — in Spain, Italy, Portugal, Poland and Ukraine the single European number is 112 — if:

• after a fall the person cannot get up or put weight on a leg, the leg looks shorter and turned outwards, and the pain in the groin or hip is severe: that is how a hip fracture presents, and it is operated on within the first day or two;
• back pain is joined by weakness or numbness in the legs, numbness around the genitals, retention of urine or incontinence: these point to pressure on the spinal cord and nerves, and there it is a matter of hours.

Ask to be seen the same day, though without an ambulance, if:

• sudden back pain comes on in someone over fifty after a trivial effort — bending, coughing, lifting a bag;
• back pain keeps you awake, is worse at night, comes with fever or weight loss, or there has been a cancer in the past;
• a new dull ache appears in the thigh or groin, especially on both sides, during long-term osteoporosis treatment: this is a rare complication best caught before the bone breaks.

What raises the risk

Some causes cannot be changed; others certainly can:

• a fracture that has already happened after a minor injury — the strongest predictor of the next one;
• a hip fracture in your mother or father;
• early menopause, removal of the ovaries, long spells without periods caused by severe dieting or punishing training;
• low testosterone in men;
• medicines: steroid tablets for more than three months, hormone treatment for breast and prostate cancer, some anti-epileptic drugs, long-term use of acid-suppressing medication;
• rheumatoid arthritis, coeliac disease, Crohn's disease, previous stomach surgery — anything that impairs absorption;
• an excess of thyroid hormone or parathyroid hormone, pituitary disease, diabetes, chronic kidney disease and liver disease;
• low body weight, smoking, regular alcohol, inactivity and long spells in bed;
• frequent falls — poor eyesight, dizziness, medicines that make you drowsy.

What a bone density scan shows

Bone density is measured by a DEXA scan of the lower spine and the hip. It takes about a quarter of an hour, needs no preparation and involves very little radiation. The result comes as a T-score — how far your density differs from that of a young adult:

• above −1: normal density;
• between −1 and −2.5: low density, known as osteopenia;
• −2.5 or below: osteoporosis.

In women before the menopause, in men under fifty and in children the Z-score is used instead of the T-score: comparing them with a healthy young adult makes no sense. A low Z-score nearly always means another condition should be looked for, rather than "age-related loss".

The number is not the only reason to treat, either: the doctor also works out your overall fracture risk for the coming years using scoring tools that take in age, weight, previous fractures and medication. And the other way round: if a spinal or hip fracture has already happened after a minor injury, treatment starts regardless of the scan. Bear in mind, too, that arthritis of the spine and calcium in the wall of the aorta falsely raise the lumbar reading, in which case the hip figure is used.

Which tests rule out other causes of fragile bone

A fragile bone is not always osteoporosis, and before starting years of treatment it makes sense to exclude conditions that are treated quite differently. Blood is usually taken for calcium, phosphate, alkaline phosphatase, vitamin D, kidney and liver function, thyroid hormone, parathyroid hormone and a full blood count, and testosterone in men; coeliac antibodies and protein electrophoresis are added where indicated. What all this is looking for:

• osteomalacia — softening of bone from severe vitamin D deficiency. It causes bone pain and weakness in the thigh muscles, and it is treated with vitamin D, not with osteoporosis drugs;
• too much parathyroid hormone, with a high blood calcium, kidney stones, thirst and weakness;
• myeloma and bone secondaries — these break vertebrae too, but the pain is usually constant and worse at night;
• undiagnosed coeliac disease, an overactive thyroid, kidney disease.

It is also worth separating two conditions that are constantly confused: osteoporosis is loss of bone density, while osteoarthritis is wear of the cartilage in joints. Arthritis hurts and creaks on movement; osteoporosis stays silent until a fracture. Neither turns into the other, and they are treated differently.

Medicines that strengthen bone

Some drugs slow the breakdown of bone and others drive the building of new bone; both groups reduce the number of fractures.

Bisphosphonates are prescribed most often: as tablets taken weekly or monthly, and also as a yearly infusion. The tablet is taken in the morning on an empty stomach with a full glass of plain water, after which you must not lie down, eat or drink anything else for half an hour, or it irritates the gullet and is poorly absorbed. Heartburn and stomach pain are possible, and after an infusion a day or two of flu-like aching. Rare but recognised complications are death of a patch of jawbone (which is why dental problems are best sorted out before starting) and an unusual thigh bone fracture, whose warning signs are described above. Treatment is reviewed after three to five years.

Denosumab is given as an injection under the skin every six months. One warning matters here: it must not simply be stopped, and the next injection must not be left late. After it is withdrawn, bone loss accelerates steeply and several vertebral fractures can follow, so the switch to another drug is planned in advance.

Bone-building drugs — parathyroid hormone analogues by daily injection and romosozumab once a month — are kept for very low density, vertebral fractures that have already happened and failure of earlier treatment. The course is time-limited, and the gain must always be locked in afterwards with a drug from the first group; romosozumab is not used after a recent heart attack or stroke.

For women there are also hormonal options: raloxifene protects the spine above all but causes hot flushes and leg cramps and raises the risk of clots, while hormone replacement therapy makes sense where there are menopausal symptoms as well.

Movement, food and a home without falls

Bone responds to load, so you need weight-bearing exercise: walking, climbing stairs, dancing and, if you are up to it, running and jumping. Swimming and cycling are good for the heart but barely load the skeleton. Twice a week add strength work and, without fail, balance training. Where there have been spinal fractures a specialist sets the programme: sharp forward bends and twisting under load are ruled out.

Food should supply around a thousand milligrams of calcium a day — dairy, tinned fish with the bones, tofu, green leafy vegetables, nuts; supplements are for those who fall short. Vitamin D is needed to absorb the calcium: in summer the skin makes it, but for older and less active people that is usually not enough. The dose is decided by a doctor, and national recommendations differ. Protein matters as well: on a meagre diet bone and muscle are lost together.

And the most practical point of all: most fractures follow a fall. Clear away cables and loose rugs, put a non-slip mat in the bathroom, arrange light by the bed and in the hallway, and wear stable shoes with a back to them. Have your eyes and hearing checked once a year, and go through with your doctor any medicines that make you dizzy.

Online consultation

An online appointment is a convenient way to work out whether you need testing at all. The doctor will ask about fractures, your height when younger and now, the menopause, the medicines you take, bowel and thyroid conditions and any falls in the past year — and will say whether a bone density scan is indicated and which blood tests are worth doing before a face-to-face visit.

The format suits going over results you already have just as well: what a T-score of −2.7 means, why treatment has been advised despite a normal scan, how the drugs differ, how to take the tablet properly, what to do about side effects and when the next check is due.

What cannot be done online is measuring bone density, examining you after an injury and confirming a fracture. If you cannot put weight on a leg after a fall, or back pain comes with weakness in the legs, you do not need a consultation — you need an ambulance.

This material is for information only and does not replace medical advice.