Osteoporosis and Bone Mineral Density

Vocabulary flashcards covering the pathophysiology, risk factors, diagnosis (T-scores), and pharmacological management of osteoporosis as described in the lecture.

Osteoporosis

The most common bone disease, characterized by reduced bone density (BMD) and micro-architectural deterioration of bone tissue leading to an increased risk of fracture from minor trauma.

Peak Bone Mass

The maximum amount of bone mass reached in normal individuals between the ages of $20$ and $45$ years.

Osteoblasts

Cells responsible for bone formation.

Osteoclasts

Cells responsible for bone resorption.

Glucocorticoid-Induced Osteoporosis Risk

The risk of osteoporosis increases when the dose of prednisolone exceeds $7.5\,mg$ daily for more than $3$ months.

Colles fracture

A common osteoporotic fracture occurring at the forearm.

Kyphosis

A clinical sign of vertebral fractures characterized by height loss and an abnormal outward curvature of the spine.

Dual energy X-ray absorptiometry (DEXA)

The investigation method used to measure bone mineral density of the lumbar spine and hip.

T-score

A measurement of how many standard deviations the patient's BMD value differs from that of a young, healthy control.

Osteopenia T-score Range

T-score values between $-1.0$ and $-2.5$.

Osteoporosis T-score Threshold

A T-score value falling to $-2.5$ or below.

Normal BMD T-score

T-score values above $-1.0$.

Bisphosphonates

The first-line drugs for the treatment of osteoporosis, such as alendronic acid, which reduce bone resorption by osteoclasts.

Osteonecrosis of the jaw

A rare but significant side effect of intravenous zolendronic acid.

Denosumab

A monoclonal antibody given SC every six months that inhibits bone resorption.

Teriparitide

A fragment of $\text{PTH}$ given by daily SC injection that stimulates new bone formation.

Hormone Replacement Therapy (HRT)

Treatment with oestrogen and progestogens used to prevent postmenopausal bone loss; avoided in women over $60$ years of age due to increased risks of breast cancer and cardiovascular disease.

Standard Calcium and Vitamin D Supplementation

$1\,g$ of calcium daily and $800\,IU$ of vitamin D daily, used as an adjunct to other osteoporosis treatments.