Extreme and prolonged vitamin D deficiency can lead to the condition of soft and weakened bones in children which is called Rickets.
Vitamin D promotes the absorption of calcium and phosphorus from the gastrointestinal tract. A deficiency of vitamin D makes it difficult to maintain proper calcium and phosphorus levels in bones, which can cause rickets.
If a vitamin D or calcium deficiency causes rickets, adding vitamin D or calcium to the diet generally corrects any resulting bone problems for a child. Rickets due to a genetic condition may require additional medications or other treatment. Some skeletal deformities caused by rickets may need corrective surgery.
The most common symptoms of rickets that one may spot, are the following:
- Slow stunted growth
- Pain in the spine, legs and the pelvis region
- Muscle pain and weakness
- Softening of growth plates at the ends of a child's bones
- Skeletal deformities like bowed legs, thickened wrists and ankles, and projected breastbone
The constituent factors that contribute to a child's risk of rickets are the following:
- Age - Infants from 3 months until the age of 3 years are most susceptible to developing rickets because their skeletons are at the fastest growth phase.
- Dark skin - Children with dark skin do not react actively and strongly to sunlight as much as children with lighter skin do and in the process, they produce less Vitamin D.
- Northern latitudes - Children in geographical locations away from the sun and its benefit are more prone to developing rickets.
- Premature birth - Premature infants and newborns stand a great risk to develop rickets.
- Anti-seizure medications - Some anti-seizure medications are known to interfere with the body's capacity and ability to process Vitamin D.
- Exclusive breastfeeding - Mother's milk does not contain enough doses of Vitamin D which is a core element to prevent and ward off rickets. New borns or infants on exclusive breastfeeding should be given Vitamin D drops.
Signs and Symptoms
- Bone tenderness
- Dental problems
- Muscle weakness (rickety myopathy)
- Increased tendency for fractures (easily broken bones), especially greenstick fractures
- Skeletal deformity
- Toddlers: Bowed legs and double malleoli (genu varum)
- Older children: Knock-knees (genu valgum) or "windswept knees"
- Cranial deformity (such as skull bossing or delayed fontanelle closure)
- Pelvic deformity
- Pectus carinatum ("pigeon chest")
- Spinal deformity (such as kyphoscoliosis or lumbar lordosis)
- Growth disturbance
- Hypocalcemia (low level of calcium in the blood)
- Tetany (uncontrolled muscle spasms all over the body)
- Craniotabes (soft skull)
- Costochondral swelling (aka "rickety rosary" or "rachitic rosary")
- Harrison's groove
- Double malleoli sign due to metaphyseal hyperplasia
- Widening of wris raises early suspicion, it is due to metaphyseal cartilage hyperplasia
An X-ray in advanced rickets shows : bow legs (outward curve of long bone of the legs) and a deformed chest. Changes in the skull also occur causing a distinctive "square headed" appearance (Caput Quadratum).
Diagnosis involves examination where the doctor will press the child's bones quite gently to check for any abnormalities. In this routine examination, the doctor will look out for anomalies such as:
- Softer skull bones and delay in the closure of the soft spots called fontanelles in babies.
- Exaggerated bowing of legs in toddlers though it is perfectly normal and healthy for toddlers to display some bow-leggedness, which goes away on its own as they grow up.
- Abnormalities in the rib cages, which can flatten and cause breastbones to protrude [ pigeon chest ].
- Larger and thicker than normal wrists and ankles.
- X-rays of affected bones are done to reveal bone deformities.
- Blood and urine tests are done to detect and diagnose and also, to monitor progress of treatment.
The usual line of treatment for rickets is prescription of Vitamin D and calcium supplements. The medications are effective if they are followed per the doctor's directions in terms of dosage which is dependent on the size and the age of the child. Excess prescription or consumption of Vitamin D can be dangerous.
In case of skeletal and spinal deformities like bowed legs, the doctor may recommend special bracing to correct or re-position the child's body appropriately as the bones grow. A lot of severe skeletal deformities would mean the child will require more surgical procedures.