OSTEOMALACIA AND RICKETS

Osteomalacia means "soft bones". It is not the same as osteoporosis. It is not very commonly seen in developed societies, but is still encountered in poor or developing nations where the standards of nutrition are poor.

Osteoid, or uncalcified bone, is bone protein matrix, composed primarily of type 1 collagen. When there is insufficient calcium or with some kinds of osteoblast dysfunction, the osteoid does not mineralize properly, and it accumulates. Alternatively, many cases of osteomalacia are related to abnormalities in vitamin D function.

When the newly formed bone of the growth plate does not mineralize, the growth plate becomes wide and irregular. This results in the clinical diagnosis of rickets, and is seen only in children because adults no longer have growth plates. A child with rickets may have bowing of the legs (see X-ray). When the remodeled bone does not mineralize, osteomalacia occurs, and this happens in all ages.

Diagnosis

Osteomalacia may be suspected on a clinical basis, but the most reliable way to establish the diagnosis is with a bone biopsy.

What treatment is available?

Regular daily supplements of vitamin D and calcium are usually used for people with simple vitamin D deficiency, but some people have a single injection vitamin D, in the form of calciferol. This is stored in the body and can last up to a year before another injection may be needed. People with vitamin D deficiency due to intestinal problems are best treated with calciferol. Most people with osteomalacia find their pain is reduced about two weeks after the injection. Extra calcium may also be needed while bone is healing.