Osteomalacia is a weakening of the bones. Problems with bone formation or with the bone building process cause osteomalacia.
Osteomalacia isn’t the same as osteoporosis. Osteoporosis is a weakening of living bone that has already been formed and is being remodeled.
Osteomalacia is most commonly caused by a lack of vitamin D. Vitamin D is an important nutrient that helps you absorb calcium in your stomach.
Vitamin D also helps maintain calcium and phosphate levels for proper bone formation. It’s made within the skin from exposure to ultraviolet (UV) rays in sunlight. It can also be absorbed from foods like dairy products and fish.
Low levels of vitamin D mean that your body cannot process the calcium your bones need for structural strength. This can result from a problem with diet, lack of sun exposure, or a problem with your intestines.
If you’ve had surgery to remove parts of your stomach or small intestine, you may also have a problem absorbing vitamin D or breaking down food to release it.
Certain conditions can interfere with the absorption of vitamin D:
- Celiac disease can damage the lining of your intestines and prevent the absorption of key nutrients like vitamin D.
- Certain types of cancer can interfere with vitamin D processing.
- Kidney and liver disorders can affect the metabolism of vitamin D.
- A diet that doesn’t include phosphates can cause phosphate depletion, which can also lead to osteomalacia.
- Phenytoin and phenobarbital are drugs used to treat seizures. They can also cause osteomalacia.
The symptoms of osteomalacia include the following.
- Bones that fracture very easily are the most common symptom.
- Another symptom is muscle weakness. This happens because of problems at the location where the muscle attaches to bone. You may have a hard time walking and may develop a waddling gait.
- Bone pain, especially in your hips, is also a very common symptom. This dull, aching pain can spread from your hips to your lower back, pelvis, legs, and even your ribs.
If you also have very low levels of calcium in your blood, you may have:
- irregular heart rhythms
- numbness around your mouth
- numbness in your arms and legs
- spasms in your hands and feet
Blood tests that show the following can suggest you may have osteomalacia or another bone disorder:
- low levels of vitamin D
- low levels of calcium
- low levels of phosphorus
You may also be tested for alkaline phosphatase isoenzymes. High levels of these indicate osteomalacia.
Another blood test can check your levels of parathyroid hormone. High levels of this hormone suggest insufficient vitamin D and other related problems.
X-rays and other imaging tests can show small cracks in the bones throughout your body. These cracks are called Looser’s transformation zones. Fractures can begin there with even small injuries.
A bone biopsy may be required to definitively diagnose osteomalacia. A needle is inserted through your skin and muscle and into your bone to obtain a small sample. That sample is put on a slide and examined under a microscope.
Usually, an X-ray and blood tests are enough to make a diagnosis and a bone biopsy isn’t necessary.
If osteomalacia is detected early, treatment can be as simple as taking oral supplements of vitamin D, calcium, or phosphate.
If you have absorption problems due to intestinal injury or surgery, or if you have a diet low in key nutrients, this may be the first line of treatment. In rare cases, you can take vitamin D as an injection through your skin or intravenously through a vein in your arm.
You may also be asked to spend some time outdoors in sunlight for your body to make sufficient vitamin D within your skin.
If you have other underlying conditions that affect vitamin D metabolism, they need to be treated. Liver cirrhosis and kidney failure must be treated to reduce osteomalacia.
In severe cases of osteomalacia or rickets, children may have to wear braces or have surgery to correct bone deformation
If it’s left untreated, osteomalacia will lead to many broken bones and severe deformity.
With an increase in vitamin D, calcium, and phosphorus, improvements can be seen in a few weeks. Complete healing of the bones takes about six months.
Symptoms can return if sufficient vitamin D isn’t available. They’ll also return if you stop taking supplements or if you have underlying health conditions like kidney failure that aren’t addressed. Talk to your doctor to create a treatment plan.