Osteomalacia is a metabolic bone disease characterized by inadequate mineralization of bone. The primary defect is a deficiency in activated vitamin D (calcitriol), which promotes calcium absorption from the gastrointestinal tract and facilitates mineralization of bone. Osteomalacia may result from failed calcium absorption (malabsorption) or excessive loss of calcium (celiac disease, biliary tract obstruction, chronic pancreatitis, bowel resection) and loss of vitamin D (liver and kidney disease). Additional risk factors include severe renal insufficiency, hyperparathyroidism, prolonged use of anticonvulsant medication, malnutrition, and insufficient vitamin D (e.g., from inadequate dietary intake or inadequate sunlight exposure).

• Bone pain and tenderness
• Muscle weakness from calcium deficiency
• Waddling or limping gait
• Pathologic fractures
• Skeletal deformities (spinal kyphosis and bowed legs); often, compression of vertebrae, shortening patient's trunk
• Weakness and unsteadiness, presenting risk of falls and fractures

• X-ray studies are conducted, and bone biopsy shows increased osteoid (demineralized bone matrix).
• Laboratory studies show low serum calcium and phosphorus levels, moderately elevated alkaline phosphatase level, and decreased urine calcium and creatinine excretion.

Physical, psychological, and pharmaceutical measures are used to reduce the patient's discomfort and pain.

• Underlying cause is corrected when possible (e.g., diet modifications, vitamin D and calcium supplements, sunlight).
• If osteomalacia is caused by malabsorption, increased doses of vitamin D, along with supplemental calcium, are usually prescribed.
• Exposure to sunlight may be recommended.
• If osteomalacia is dietary in origin, a diet with adequate protein and increased calcium and vitamin D is provided.
• Long-term monitoring is undertaken to ensure stabilization or reversal.
• Orthopedic deformities may be treated with braces or surgery (osteotomy).

For more information, see Chapter 41 in Hinkle, J. L., & Cheever, K. H. (2018). Brunner and Suddarth's textbook of medical-surgical nursing (14th ed.). Philadelphia, PA: Lippincott Williams & Wilkins.

Gerontologic Considerations

A nutritious diet is particularly important in older adults. Adequate intake of calcium and vitamin D is promoted. Because sunlight is necessary for synthesizing vitamin D, patients should be encouraged to spend some time in the sun, for at least 10 minutes and up to an hour daily.