Rickets

What is rickets?

Rickets is a condition in which a child’s bones become soft, weak, and prone to bending or breaking because they do not harden (mineralize) properly while they are still growing. Bones gain their strength from minerals, mainly calcium and phosphate. Vitamin D helps the body absorb these minerals from food. When a growing child does not have enough vitamin D, calcium, or phosphate, the growth plates (the areas of soft cartilage at the ends of long bones where new bone forms) cannot turn into hard bone as they should. The result is bones that bend under the child’s own weight and grow more slowly than expected.

Rickets affects children, because it is a disease of bones that are still growing. The same problem in adults, whose growth plates have already closed, is called osteomalacia (softening of mature bone). Rickets is most often seen in infants and toddlers between about 6 and 36 months of age, a time of rapid growth when the need for vitamin D and calcium is high. In most parts of the world the most common form is nutritional rickets, caused by too little vitamin D, too little dietary calcium, or both. Less common forms are inherited and involve problems with how the body handles phosphate or vitamin D.

Although rickets was once widespread, it is now uncommon in many countries thanks to vitamin D supplements and fortified foods. It still occurs, however, particularly in children who have limited sun exposure, are exclusively breastfed without vitamin D drops, follow very restricted diets, or have darker skin. Children with rickets are usually cared for by a pediatrician (a doctor who specializes in children’s health), often together with a pediatric endocrinologist (a specialist in hormones and metabolism) or a pediatric orthopedic surgeon (a specialist in children’s bones and joints).

Rickets symptoms

Rickets symptoms develop gradually and can be easy to miss in the early stages. Because the condition affects bones, muscles, growth, and sometimes the level of calcium in the blood, the signs can vary from child to child. Common rickets symptoms include:

• Bowed legs (legs that curve outward at the knees) or knock knees (knees that angle inward), usually noticed once a child starts standing and walking
• Delayed growth or short stature compared with other children of the same age
• Bone pain or tenderness, especially in the legs, spine, and pelvis; a young child may be reluctant to walk or may cry when picked up
• Muscle weakness, floppiness, or reduced muscle tone
• Delayed motor milestones, such as sitting, crawling, or walking later than expected
• Thickened wrists and ankles caused by widened growth plates
• A soft skull in infants, or a soft spot (fontanelle) on the head that closes later than usual
• Chest changes, such as a row of bead-like bumps along the ribs (sometimes called a rachitic rosary) or a breastbone that sticks out
• Dental problems, including teeth that come in late, weak enamel, and frequent cavities
• Fractures that happen with little or no obvious injury

Symptoms often differ by age and stage. In young infants who are not yet walking, the earliest signs may be irritability, poor feeding, a soft skull, and slow growth. In some infants, very low blood calcium can cause muscle cramps, twitching, or seizures before any bone changes are visible; these are urgent signs. In toddlers and older children, the classic bending of the legs, waddling walk, and thick wrists and ankles become more obvious as the child bears weight on softened bones.

In inherited forms of rickets, such as X-linked hypophosphatemic rickets (a genetic condition in which the kidneys lose too much phosphate), children may look healthy at birth and only develop leg bowing, slow growth, and bone or joint pain in the second or third year of life. These children often have normal vitamin D levels, so the pattern of symptoms alongside blood tests helps doctors tell the types apart.

Causes and risk factors

Understanding rickets causes helps explain both treatment and prevention. In simple terms, rickets happens when a growing child’s bones do not receive, or cannot use, enough calcium and phosphate. Several different problems can lead to this.

• Vitamin D deficiency. This is the most common cause worldwide. Vitamin D is made in the skin when it is exposed to sunlight and is also obtained from a limited number of foods and from fortified products such as some milks and cereals. Without enough vitamin D, the gut absorbs much less calcium.
• Low dietary calcium. In some regions rickets occurs in children whose diets contain very little calcium, even when vitamin D levels are reasonable. Often the two deficiencies occur together.
• Problems absorbing nutrients. Conditions that affect the gut, such as celiac disease (an immune reaction to gluten), cystic fibrosis, inflammatory bowel disease, or previous bowel surgery, can prevent vitamin D and calcium from being absorbed properly.
• Kidney and liver disease. The liver and kidneys convert vitamin D into its active form. Long-term kidney disease, in particular, can lead to a type of rickets even when vitamin D intake is adequate.
• Inherited (genetic) disorders. Some children inherit a condition that causes their kidneys to lose phosphate, or that stops their body from activating or responding to vitamin D. These forms are rare and usually do not improve with ordinary vitamin D supplements alone.
• Certain medicines. Some anti-seizure medicines and other drugs taken for long periods can interfere with vitamin D metabolism.

Certain children are at higher risk. Risk factors for nutritional rickets include being exclusively breastfed without vitamin D drops (breast milk alone contains little vitamin D), having darker skin (which makes less vitamin D from the same amount of sunlight), living in a place with long winters or high air pollution, spending very little time outdoors, wearing clothing that covers most of the skin, and being born to a mother who was herself low in vitamin D during pregnancy. Premature birth, very restricted or vegan diets without fortified foods or supplements, and a family history of bone disease also raise the risk.

Rickets diagnosis

Rickets diagnosis begins with a careful medical history and a physical examination. The doctor will ask about the child’s diet, feeding history, use of vitamin supplements, time spent outdoors, growth pattern, and any family history of bone problems or short stature. During the examination, the doctor looks for leg bowing, swollen wrists and ankles, chest wall changes, a soft skull, muscle weakness, and signs of delayed development, and checks the child’s height and weight against standard growth charts.

Because several conditions can cause bowed legs or slow growth, doctors confirm rickets with tests rather than by appearance alone. The main tests include:

• Blood tests. These typically measure 25-hydroxyvitamin D (the main storage form of vitamin D in the blood), calcium, phosphate, alkaline phosphatase (an enzyme that is usually high when bone is actively trying to repair itself), and parathyroid hormone (a hormone that rises when calcium is low). The pattern of results helps distinguish vitamin D deficiency from calcium deficiency and from inherited phosphate-wasting conditions.
• X-rays. X-rays of the wrists, knees, or ankles are the standard way to confirm rickets. In active rickets, the growth plates look widened, frayed, and cup-shaped, and the bones may appear less dense than normal. X-rays of the legs also show how severe any bowing is, and follow-up images can show healing once treatment starts.
• Urine tests. Measuring calcium and phosphate in the urine can help identify kidney-related causes, particularly conditions in which the kidneys leak phosphate.
• Kidney and liver function tests. These check for underlying organ disease that might be affecting vitamin D activation.
• Genetic testing. If blood results point to an inherited form, or if the child does not improve with standard treatment, your doctor may recommend genetic tests to identify the specific condition and guide treatment for the child and possibly other family members.

Rarely, a bone density scan or a bone biopsy (removing a tiny sample of bone) may be considered, but these are not needed for most children. In many cases the combination of a suggestive history, typical examination findings, characteristic X-ray changes, and supporting blood tests is enough to confirm the diagnosis and identify the cause.

Rickets treatment options

Rickets treatment depends on the cause, the child’s age, and how severe the bone changes are. The overall goals are to correct the mineral or vitamin shortage, allow the bones to heal and harden, restore normal growth, and prevent or correct deformities. Treatment is generally overseen by a pediatric team; at Acibadem, for example, this is managed within Pediatrics, with input from pediatric endocrinology and orthopedics when needed.

Vitamin D and calcium replacement. For nutritional rickets, the standard treatment is vitamin D given by mouth, usually together with calcium, either as supplements or through a diet richer in calcium. Your doctor will choose a dose and schedule based on the child’s age and blood results. Some children receive a daily dose over several weeks to months; in certain situations doctors may use a larger single or short-course dose followed by a maintenance dose. Blood tests are repeated after a few weeks to check that levels are rising safely, and X-rays are often repeated after a few months to confirm that the growth plates are healing. Once the deficiency is corrected, most children continue on a lower, long-term preventive dose of vitamin D.

Treating the underlying condition. When rickets is caused by a gut, kidney, or liver problem, that condition must be managed alongside the bone disease. For example, a child with celiac disease needs a gluten-free diet so that nutrients can be absorbed again, and a child with kidney disease is treated by a kidney specialist with adjusted forms of vitamin D and careful mineral management.

Treatment for inherited forms. Children with hypophosphatemic rickets usually need phosphate supplements taken several times a day together with an active form of vitamin D (such as calcitriol), because ordinary vitamin D alone does not work. For some genetic forms, newer targeted medicines that act on the hormone signals controlling phosphate loss may be considered by a specialist. These treatments are typically long-term and require regular monitoring of blood and urine, as well as kidney checks.

Observation and monitoring of deformities. Mild leg bowing often improves on its own over months to years once the underlying problem is corrected and the bones harden, particularly in younger children who still have a lot of growth ahead. Doctors usually recommend watchful waiting with periodic examinations and X-rays before considering any procedure.

Bracing. Braces are not routinely used for rickets, but in selected cases a doctor may suggest one to support a limb while the bone is healing. Their benefit is limited, and they are not a substitute for correcting the mineral deficiency.

Surgery. If significant bowing persists after the rickets has healed, or if it causes pain or difficulty walking, a pediatric orthopedic surgeon may discuss surgery. Options include guided growth surgery, in which a small plate is placed on one side of the growth plate to gently straighten the leg as the child grows, or an osteotomy, in which the bone is cut and realigned. Surgery is generally only performed once the rickets itself is under control, since operating on soft bone carries a higher risk of the deformity returning.

Rehabilitation and support. Physical therapy may help children regain strength, improve walking, and catch up on delayed motor skills. Dental care is also important, because rickets can affect tooth enamel. Families usually receive dietary guidance on calcium-rich foods and on safe sun exposure appropriate for the child’s skin type and location.

Living with rickets and outlook

For most children with nutritional rickets, the outlook is good when the condition is recognized and treated. Blood levels usually improve within weeks, and X-rays typically show healing of the growth plates within a few months. Bone pain and muscle weakness often ease relatively early in treatment, and many children resume normal growth. Leg bowing frequently improves over time as the bones harden and the child grows, although in some children a degree of deformity remains and may need orthopedic follow-up or, less commonly, surgery. Very severe or long-standing rickets can leave permanent changes in height or bone shape, which is one reason early diagnosis matters.

Children with inherited forms of rickets generally need lifelong care. With consistent treatment and monitoring, many grow and lead active lives, but they may have ongoing issues such as shorter stature, joint pain, dental problems, or hearing changes, and they usually continue to see specialists into adulthood. Because these conditions run in families, genetic counseling may be offered.

Day-to-day, families are usually asked to give medicines consistently, attend follow-up appointments for blood tests and growth checks, and maintain a diet that provides adequate calcium and vitamin D. Children who have had rickets can typically take part in normal play and school activities once their doctor confirms that their bones have healed enough, though heavy impact sports may be limited during recovery. Preventive vitamin D supplementation is generally continued to reduce the chance of the problem returning.

Frequently asked questions

What is the most common cause of rickets?

Worldwide, the most common rickets cause is a shortage of vitamin D, often combined with low calcium intake. Vitamin D is needed for the gut to absorb calcium, so a lack of it leaves bones without the minerals they need to harden. Infants who are exclusively breastfed without vitamin D drops and children with limited sun exposure are among those most affected. Less common causes include gut, kidney, or liver disease and inherited disorders of phosphate or vitamin D handling.

What are the first signs of rickets in a baby?

Early rickets symptoms in infants can be subtle. Parents or doctors may notice a soft skull, a soft spot on the head that is slow to close, irritability, poor feeding, slow weight gain, floppiness, or delays in sitting and crawling. In some babies, low blood calcium causes muscle twitching or seizures before bone changes are visible. Because these signs can have many causes, a doctor’s assessment and blood tests are needed to know whether rickets is responsible.

How is rickets diagnosed?

Rickets diagnosis relies on a combination of history, physical examination, blood tests, and X-rays. Doctors usually measure vitamin D, calcium, phosphate, alkaline phosphatase, and parathyroid hormone in the blood, and take X-rays of the wrists or knees to look for widened, frayed growth plates. Urine tests and, in some cases, genetic testing help identify kidney-related or inherited forms. Bowed legs alone are not enough to confirm the diagnosis, since other conditions can look similar.

Can rickets be cured?

Nutritional rickets can usually be corrected with vitamin D and calcium, and in many children the bones heal well over a period of months. Whether a child’s legs straighten fully depends on how severe the bowing was and how much growth remains. Inherited forms of rickets cannot be cured in the same way but can often be managed effectively with long-term treatment and monitoring. Your doctor can explain what to expect based on the specific type and severity.

How long does rickets treatment take?

The initial phase of rickets treatment for vitamin D deficiency commonly lasts several weeks to a few months, after which blood tests and X-rays are repeated to confirm healing. A lower maintenance dose of vitamin D is then usually continued long term to prevent recurrence. Improvement in leg shape can take considerably longer, sometimes years, as the child grows. Children with inherited or kidney-related rickets typically need ongoing treatment rather than a fixed course.

Can adults get rickets?

Rickets, strictly speaking, affects children whose bones are still growing. When the same lack of vitamin D or minerals softens fully grown bones in adults, the condition is called osteomalacia. Adults with osteomalacia may have bone pain, muscle weakness, and fractures, and it is treated with similar principles, mainly by correcting the underlying vitamin D or mineral deficiency and addressing any medical cause.

Will my child need surgery for rickets?

Most children with rickets do not need surgery. Once the mineral deficiency is corrected, leg bowing often improves gradually with growth. Surgery is generally reserved for children whose significant deformity persists after the bone has healed, or whose bowing causes pain or walking difficulties. When it is needed, a pediatric orthopedic surgeon may use guided growth techniques or realign the bone, usually only after confirming that the rickets is under control.

When to see a doctor

Talk to your child’s doctor if you notice bowed legs or knock knees that seem to be getting worse, slow growth compared with other children of the same age, delays in sitting, standing, or walking, unusual tiredness or reluctance to walk, thickened wrists or ankles, or teeth that are late to appear or decay easily. These signs do not necessarily mean rickets, but they should be checked. It is also reasonable to ask about vitamin D supplements if your baby is exclusively breastfed, has darker skin, or spends little time outdoors.

Seek urgent medical care if a child has any of the following red-flag signs, which may indicate dangerously low blood calcium or a serious complication:

• A seizure or convulsion, especially in a baby or toddler with no history of seizures
• Muscle spasms, cramps, or twitching of the hands, feet, or face
• Difficulty breathing, noisy breathing, or a high-pitched sound when breathing in
• A suspected broken bone, or severe bone pain after a minor bump or fall
• A baby who is unusually floppy, difficult to wake, or refusing to feed
• Sudden inability to stand or walk in a child who could previously do so

Early recognition and treatment give a child the best chance of healing without lasting bone changes, so it is better to have concerns assessed promptly than to wait and see.