BONE & JOINT DISORDERS (ARTHRITIS)

 

OSTEOPOROSIS – INVESTIGATIONS

 

A) Screening

 

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.