BONE & JOINT DISORDERS (ARTHRITIS)
OSTEOPOROSIS – INVESTIGATIONS
The reduced bone mass and risk of fracture can be measured by a simple, non-invasive test called BMD (bone mineral density) test orbone densitometry. As per recommendations of the National Osteoporosis Foundation (USA), BMD test may be advised:
- For females above 65 years of age
- For postmenopausal females below 65 years of age if one or more risk factors are present
- For postmenopausal females having fracture
- If the test is going to help in deciding initiation of therapy for osteoporosis.
B) Detection of Osteoporosis can be done by:
- Bone density measurements (Bone densitometry): Osteoporosis can be detected at an early stage with the help of Bone densitometry. It can be done by:
o SPA (single photon absorptiometry)
o DPA (dual photon absorptiometry)
o DEXA (dual energy x-ray absorptiometry)
o QCT (quantitative computed tomography)
- X-ray: Changes in x-ray are seen only after loss of approximately 30-40% of bone mass. X-ray spine may show decreased bone density, loss of horizontal trabeculations, biconcave vertebral bodies, ‘codfish’ vertebrae and compression fractures. X-ray pelvis may show demineralization of femoral neck and head.
C) Monitoring of Osteoporosis can be done by estimation of:
- Serum bone specific alkaline phosphatase and osteocalcin.
- Urinary excretion of hydroxyproline and pyridinolines (free and total).
D) Other investigations that may be advised include:
- Serum calcium, inorganic phosphorus and alkaline phosphatase.
- Serum levels of thyroid hormone, parathyroid hormone, estrogen or testosterone to exclude the causes of secondary osteoporosis.