Osteomalacia

DEFINITION

Osteomalacia refers to a softening of your bones, often caused by a vitamin D deficiency. Soft bones are more likely to bow and fracture than are harder, healthy bones.

Osteomalacia is not the same as osteoporosis, another bone disorder that also can lead to bone fractures. Osteomalacia results from a defect in the bone-building process, while osteoporosis develops due to a weakening of previously constructed bone.

Muscle weakness and achy bone pain are the major symptoms of osteomalacia. Treatment for osteomalacia involves replenishing low levels of vitamin D and calcium and treating any underlying disorders that may be causing the deficiencies.

CAUSES

Your body uses calcium and phosphate to build strong bones. Osteomalacia may occur if you don’t get enough of these minerals in your diet or if your body doesn’t absorb them properly. These problems may be caused by:

• Vitamin D deficiency. Sunlight produces vitamin D in your skin. Your body needs vitamin D to process calcium. Osteomalacia can develop in people who spend little time in sunlight, wear very strong sunscreen or remain covered while outside.

  People who live in areas where sunlight hours are short or eat a diet low in vitamin D can develop osteomalacia. Vitamin D deficiency is a common cause of osteomalacia worldwide.

• Certain surgeries. Normally, the stomach breaks down food to release vitamin D and other minerals that are absorbed in the intestine. This process is disrupted if you have surgery to remove part or all of your stomach (gastrectomy), and may result in osteomalacia. Surgery to remove or bypass your small intestine also can lead to osteomalacia.
• Celiac disease. In this autoimmune disorder, the lining of your small intestine is damaged by consuming foods containing gluten, a protein found in wheat, barley and rye. A damaged intestinal lining doesn’t absorb nutrients, such as vitamin D, as well as a healthy one does.
• Kidney or liver disorders. Problems with your kidneys or liver can interfere with your ability to process vitamin D.
• Drugs. Some drugs used to treat seizures, including phenytoin (Dilantin, Phenytek) and phenobarbital, can cause osteomalacia.

SYMPTOMS

In the early stages, you may have no osteomalacia symptoms, although signs of osteomalacia may be apparent on X-ray pictures or other diagnostic tests. As osteomalacia worsens, you may experience bone pain and muscle weakness.

The dull, aching pain associated with osteomalacia most commonly affects the lower back, pelvis, hips, legs and ribs. The pain may be worse at night, or when you’re putting weight on affected bones.

Decreased muscle tone and leg weakness may cause a waddling gait and make it difficult for you to get around.