Osteomalacia means "soft bones." Osteomalacia is a disease that weakens bones and can cause them to break more easily. It is a disorder of decreased mineralization, which results in bone breaking down faster than it can re-form. It is a condition that occurs in adults. Osteomalacia, particularly when caused by a lack of vitamin D, can result in:
-- pain felt in the bones
-- muscle weakness
-- slight cracks in the bone

Bone pain is felt most often in the legs, groin, upper thighs and knees, and sometimes in the feet when you stand, walk or run. Sitting or lying down to rest can often ease the pain. Sometimes a minor knock on a bone such as the shin will feel unusually painful. As the condition gets worse, pain can be felt everywhere and simple movements can hurt.

Muscles may become weak or feel stiff. The weakness tends to affect the thighs and the muscles in the shoulders and main trunk of the body. This can make it difficult to climb stairs, get up from a chair without using the arms for support and, in very severe cases, get out of bed.