Rickets

About rickets

Bone development in children

When you’re a child, your bones continually grow and develop. This growth is usually at its peak when you’re an infant and during puberty.

The strength of your bones depends on the amount of minerals laid down in the inner core (matrix). This is done through a process called mineralisation. Minerals such as calcium and phosphorus are absorbed from the food you eat and deposited in your bones. You also need vitamin D for this process because it helps your body to absorb calcium. It also makes sure it gets to where it's needed (for example your bones or teeth).

As a child, mineralisation helps your bones to grow and develop, whereas as an adult, it maintains and repairs them.

Rickets

Rickets affects how children’s bones grow and develop. Their bones don’t get enough of the minerals they need to grow, so they can become soft and weak. As children grow and get heavier, this increase in body weight can cause their soft, weak bones to become bowed and misshapen.

Soft bones can also affect adults; this condition is called osteomalacia.

Symptoms of rickets

The symptoms of rickets can include:

  • soft skull bones or skull deformities
  • delayed development
  • a protruding abdomen (tummy)
  • poor growth (children may be short for their age)
  • scoliosis
  • floppy limbs and body because of muscle weakness
  • teeth taking longer than usual to come through
  • weak tooth enamel that may lead to tooth decay
  • painful bones – particularly those in the arms, legs, spine and pelvis (although this is rare)
  • fractures, as the result of a fall

Children with severe rickets may also have low levels of calcium. This can cause muscle spasms.

Children with rickets may also have problems such as:

  • thick ankles, wrists or knees (‘knock-knees’)
  • legs that curve outwards (‘bow legs’)
  • a breastbone that sticks out (‘pigeon chest’)
  • ribs that stick out
  • a protruding forehead
  • spinal deformities (for example, a hunched back)
  • pelvic deformities

If your child has any of these symptoms or skeletal deformities, see your GP.

Causes of rickets

Rickets is usually caused by a lack of vitamin D and/or calcium. Vitamin D is produced naturally by your body when your skin is exposed to sunlight. It can also be found in some foods, such as oily fish. Children may get enough vitamin D during summer by spending frequent short spells in the sun without wearing sunscreen. The exact time you need is different for everyone, but is typically only a few minutes in the middle of the day.

However, don’t let your child’s skin burn. If your child doesn't get much sun exposure and particularly during winter months, taking 10 micrograms of vitamin D a day – or 7 to 8.5 micrograms per day if he or she is aged between six months and five years – can help to make sure he or she gets enough.

Calcium comes from your diet – dairy foods are a good source of calcium. Both calcium and vitamin D are essential for strong, healthy bones.

Rickets is more common in children from Asian, African-Caribbean and Middle Eastern origins. This is because dark skin needs to be in the sun for much longer than fair skin to get enough vitamin D. However, children with fair skin can also be at risk if they don't go outside in the sunlight very often or frequently cover up.

Children who eat diets that cut out certain food groups (for example, vegetarians and vegans) may also be at risk of developing rickets. This is because they may not be getting enough calcium or vitamin D in their diet.

Infants who are breastfed may have low levels of vitamin D if their mother is lacking vitamin D. Formula milk is fortified with vitamin D.

Hypophosphataemic rickets

Hypophosphataemic rickets is a rare inherited form of rickets. If your child has this condition, he or she will be unable to absorb enough phosphates or calcium to build strong, healthy bones.

Metabolic disorders

Metabolic disorders are when your body can’t make energy properly from the food you eat. This causes you to have too much or too little of the substances that keep you healthy. They can make it difficult for your child to process and absorb vitamin D. They include vitamin D-dependent rickets type I or vitamin D-dependent rickets type II. Both of these types are inherited conditions.

Secondary rickets

Rickets can also develop as a result of other conditions, such as liver disease or kidney disease.

Diagnosis of rickets

Your GP will ask about your child's symptoms and examine him or her.

If your GP thinks your child may have rickets he or she will arrange for your child to have a blood test. This will measure the amount of vitamin D, calcium and phosphorous in your child's blood. Your GP may refer your child to a hospital for an X-ray, usually of their knees (if your child is under three) or their wrists.

If your child is diagnosed with rickets, he or she will be referred to a paediatrician (a doctor who specialises in children’s health) for treatment and monitoring.

Treatment for rickets

Rickets is treated with daily vitamin D and calcium supplements. Alternatively your child may have a vitamin D injection once a year instead of daily vitamin D supplements.

It's important to give your child the dose of supplements that your GP recommends. If your child has too much vitamin D, he or she may develop vitamin D toxicity. This causes an excess of calcium in the body (hypercalcaemia).

For hypophosphataemic rickets and inherited vitamin D-dependent rickets, your child will have specialist treatment from a paediatrician.

If there are any other underlying conditions related to your child's rickets, such as a metabolic disorder or kidney disease, these will also be treated.

Special considerations

If you’re pregnant or breastfeeding, it's important to make sure you get enough vitamin D. While you’re pregnant, your baby will get all the vitamin D he or she needs directly from you. This will be stored in their body and your baby will use this supply over the first few months after they are born. After this, unless your baby gets vitamin D from another source, these stores will begin to run out.

Breast milk is the best source of nutrition for your baby. However, it contains very little vitamin D, so there is a risk that your baby may not get enough. If you’re pregnant or breastfeeding, take at least 10 micrograms of vitamin D supplements a day. This can reduce the risk of your baby developing rickets. The UK Department of Health recommends that children aged between six months and five years take 7 to 8.5 micrograms of vitamin D per day.

Prevention of rickets

There are several things you can do to help prevent children from getting rickets.

Diet

Make sure your child eats plenty of foods that are rich in calcium and vitamin D.

Good sources of calcium include:

  • dairy products (for example, milk, yoghurt and cheese)
  • bread made with fortified flour
  • soya beans and tofu
  • leafy green vegetables (for example, broccoli and cabbage but not spinach)

It’s important that your child gets enough vitamin D to reduce their risk of developing rickets. Diet alone isn't usually enough to give your child his or her daily requirement of vitamin D. However, you can get some vitamin D from:

  • oily fish (for example, sardines and mackerel)
  • eggs (cooked, not raw)
  • margarine
  • breakfast cereals fortified with vitamin D

Sun

Vitamin D is produced naturally by your body when your skin is exposed to sunlight. Your child may get enough vitamin D during summer by spending frequent short spells in the sun without wearing sunscreen. However, the exact time you need is different for everyone, but is typically only a few minutes in the middle of the day. However, a child’s skin can be easily damaged by the sun, so it’s very important not to let your child’s skin burn and to use sunscreen for longer periods in the sun.

You will need to be more careful with babies and toddlers as they have very sensitive skin that can burn easily. Always keep babies and toddlers in the shade, or cover them up. For more information about safety in the sun, see sun care.

Supplements

The Department of Health recommends that children aged six months to five years should take supplements that contain 7 to 8.5 micrograms of vitamin D daily, unless they drink 500 ml (one pint) or more of formula milk a day. This is especially important for babies being breastfed or children who are at risk (for example Asian, African-Caribbean and Middle Eastern). Women who are pregnant or breastfeeding should take at least 10 micrograms a day.

Some families may be eligible for free vitamin D supplements from the government-run Healthy Start scheme.

I thought rickets had been wiped out in the UK; how has it re-emerged?

Answer

Rickets is often considered a health condition of the past but it’s returned to the UK and other developed countries in recent years. This is often because of vitamin D deficiency in a child’s diet (nutritional rickets). This has mainly been in children of Asian, African-Caribbean and Middle Eastern descent.

Explanation

Nutritional rickets had been largely wiped out in the UK thanks to the introduction of food fortification in the 1940s (vitamin D was added to margarine and some breakfast cereals). However, in the 1970s, as more people from different ethnic groups immigrated to the UK, it has reappeared.

Children of Asian, African-Caribbean and Middle Eastern origin are more likely to get rickets because their skin is darker. Children with dark skin need a lot more sunlight to get enough vitamin D than those with light skin. The sun in the UK isn’t strong enough to give these children the amount of vitamin D they need, especially during the winter months when the sun is much weaker.

Some cultures also require teenagers to be completely covered; this can mean that they have a limited exposure to the sun. Children who don't go outside very often or who wear very high factor sunscreen when they are outside may also be at risk of developing rickets.

If your child is a picky or fussy eater, he or she may not be getting enough calcium or vitamin D for healthy development.

There are several things you can do to help prevent your child from getting rickets.

  • Make sure he or she gets plenty of calcium and vitamin D in their diet. Good sources of calcium include dairy products, bread made with fortified flour and leafy green vegetables. Vitamin D can be found in oily fish, cooked eggs, and fortified margarine and breakfast cereals.
  • Encourage your child to play outside. However, babies and young children have very sensitive skin and can burn easily. It's especially important to protect your child from the sun around midday; use sunscreen and keep him or her mostly covered up or in the shade during this time.
  • Give your child vitamin D supplements if necessary. The UK Department of Health recommends that all children between six months and five years old, and breastfed infants from one month of age take vitamin D supplements if their mother hasn’t taken vitamin D supplements during pregnancy. This is especially important for babies who are breastfed or children from ethnic groups who are more at risk.

How can I find out if my child is eligible for free vitamin D supplements?

Answer

In the UK, the Government recommends that all children between six months and five years should take vitamin D supplements to prevent rickets. For some children these can be obtained free of charge through the Government's Healthy Start scheme.

Explanation

Babies and children need a healthy, balanced diet to help them grow and develop; there are certain nutrients that are essential for this growth. To prevent rickets, the Department of Health recommends that all children between six months and five years take supplements of vitamin D every day. This is especially important for babies who are breastfed or children from ethnic groups who are more at risk.

The UK Government runs Healthy Start, a scheme in which some children under the age of five can receive supplements, including vitamin D, free of charge. The scheme can also provide free vitamin D supplements for women who are pregnant or breastfeeding.

You qualify for Healthy Start if you're pregnant and/or have a child under the age of four, and your family are:

  • receiving Income Support or income-based Jobseeker's Allowance
  • receiving Child Tax Credit and have a family income below a certain limit

You will also qualify for Healthy Start if you’re pregnant and under the age of 18.

If you don't qualify for Healthy Start, you can buy vitamin D supplements from your pharmacist. You can buy drops instead of tablets for babies and children. Always read the patient information leaflet that comes with your child’s supplements and if you have any questions, ask your pharmacist or GP for advice.

Will my child need surgery?

Answer

Treatment with vitamin D can often be very successful and although it can take many months, the condition can get better without the need for surgery. However, if your child has severely misshapen bones and joints as a result of rickets, he or she might need to have surgery.

Explanation

As your child grows, they will get heavier and this increase in body weight can cause their soft, weak bones to become bowed and grow out of shape. Your child may then develop problems such as:

  • thick ankles, wrists or knees ('knock-knees')
  • legs that curve outwards ('bow legs')
  • spinal deformities (for example, a hunched back)
  • pelvic deformities

If your child has a skeletal deformity, his or her paediatrician may suggest surgery to help correct the problem. Ask your doctor for advice on whether your child will need surgery.

I’ve just been told my son has hypophosphataemic rickets - what is this?

Answer

Hypophosphataemic rickets is a rare form of rickets that you can inherit from your parents. There are different types of the condition but the most common – called X-linked hypophosphatemic rickets – affects about one in 20,000 newborn babies. Having hypophosphataemic rickets means your son isn’t able to absorb enough phosphates or calcium from his diet that he needs to build strong, healthy bones. Unlike the more common form of rickets, standard vitamin D treatment won’t help but there are other treatments available.

Explanation

Phosphate is important for the formation and growth of bones in children and helps to maintain the strength of your bones as an adult. Your kidneys play a large part in controlling phosphate levels in your body. They take excess phosphate out of your body (which you pass out as urine) and re-absorb phosphate into your blood when your body needs more. However, if you have hypophosphatemic rickets, your kidneys can’t re-absorb the phosphate effectively and too much phosphate is removed from your body in your urine. Therefore, you don’t have enough phosphate available in your blood for normal bone development and maintenance.

Although some children with mild hypophosphatemic rickets don’t have any symptoms, others can be short in height and develop bowed legs. As a baby their weight is normal but they often grow slowly in comparison to other children without the condition.

Treatment for hypophosphatemic rickets will aim to raise phosphate levels in your son’s blood, which will help his bones to grow normally. Phosphate is often combined with a medicine called calcitriol (a form of vitamin D). This will help to increase your son’s calcium levels by affecting the way his body absorbs calcium from his food – it will also help his body to retain calcium in his kidneys. If your son has this treatment, his condition should improve within about six to eight weeks. It’s very important for your son to attend regular appointments with his doctor so he or she can monitor the condition and adjust the treatment if necessary.

If your son has severe rickets and his legs are bowed, he may need surgery but ask your doctor for advice.