Osteoporosis

Osteoporosis is a systemic skeletal disorder characterised by low bone mass, micro-architectural deterioration of bone tissue leading to more porous bone, and an increased risk of fractures. It is the most common cause of fractures among the elderly, with common sites including the vertebrae, forearm, wrist, and hip.

Typically, there are no symptoms until a fracture occurs. Fractures can result in chronic pain and decreased ability to perform daily activities.

Signs and Symptoms

Osteoporosis is often asymptomatic until fractures occur, which are termed fragility fractures. These fractures can happen with minimal stress, such as a fall from standing height or even during normal activities like bending or coughing.

The most common fractures associated with osteoporosis are in the wrist, spine, shoulder, and hip. Vertebral fractures can cause sudden back pain, loss of height, and a stooped posture, while hip fractures usually necessitate surgery and can lead to severe complications.

Risk Factors

Risk factors for osteoporosis include both nonmodifiable and modifiable factors. Nonmodifiable factors include advanced age, female sex, and ethnicity (European or Asian ancestry).

Modifiable factors include lifestyle choices such as smoking, excessive alcohol consumption, and a diet low in calcium and vitamin D. Certain medical conditions and medications, such as glucocorticosteroids and anticonvulsants, also increase the risk of osteoporosis.

Diagnosis

Osteoporosis is diagnosed using bone density measurements, typically with dual-energy X-ray absorptiometry (DEXA). A T-score of -2.5 or lower indicates osteoporosis.

Blood tests may also be conducted to rule out other conditions that affect bone density. Conventional radiography can detect fractures and significant bone loss but is less sensitive for early disease.

Pathogenesis

The imbalance between bone resorption and bone formation is the primary mechanism of osteoporosis. Osteoclasts break down bone tissue faster than osteoblasts can rebuild it, leading to a decrease in bone mass and density.

This process is influenced by hormonal changes, particularly decreased oestrogen levels in postmenopausal women and reduced testosterone levels in older men. Calcium and vitamin D deficiencies also play a significant role.

Treatment

Lifestyle Modifications

Prevention and management of osteoporosis involve lifestyle changes such as a diet rich in calcium and vitamin D, regular weight-bearing exercise, and fall prevention strategies. Smoking cessation and reducing alcohol intake are also beneficial.

In those with coeliac disease, adherence to a gluten-free diet can improve bone density.

Medications

Bisphosphonates are the primary medications used to decrease the risk of fractures in individuals with osteoporosis. They work by inhibiting bone resorption.

Other medications include selective oestrogen receptor modulators (SERMs), hormone replacement therapy (HRT), and parathyroid hormone analogues like teriparatide. These treatments aim to increase bone density and reduce fracture risk.

Physical Therapy

Physical therapy can help improve balance, posture, and muscle strength, reducing the risk of falls and fractures. Weight-bearing and resistance exercises are particularly effective in maintaining or increasing bone density in postmenopausal women.

Prognosis

Osteoporotic fractures, especially hip fractures, are associated with increased mortality and morbidity in the elderly. Vertebral fractures can lead to chronic pain and disability, significantly impacting the quality of life.

Early diagnosis and management are very important to preventing fractures and improving outcomes for those with osteoporosis.

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Self-assessment MCQs (single best answer)

What is the primary characteristic of osteoporosis?<

Which of the following is the most common fracture site associated with osteoporosis?

Which diagnostic method is considered the gold standard for osteoporosis?

What T-score on a DEXA scan indicates osteoporosis?

Which of the following is a nonmodifiable risk factor for osteoporosis?

Which medication is primarily used to treat osteoporosis by inhibiting bone resorption?

What lifestyle modification is NOT typically recommended for osteoporosis prevention?

Which hormone's decreased levels are most associated with increased bone resorption in postmenopausal women?

What is a common complication of osteoporosis-related vertebral fractures?

Which population is at the highest risk for osteoporosis?