Osteoporosis

Suspicious Signs/Symptoms

• Height loss >3 cm

• Kyphosis

• Unexplained back pain

Definition

• Fracture from standing height or minor trauma

• ≥20% vertebral body height loss

Management

1. Lifestyle Modifications

• Smoking/Alcohol: Cease smoking, alcohol <2/day

• Calcium: 1300 mg/day (dietary preferred)

• Vitamin D: Sunlight exposure to maintain >75 nmol/L

• Exercise: Resistance/balance training 2–3x/week (30 min/session)

• Falls Prevention: Remove hazards, ensure proper footwear

• BMI: Maintain 20–25

2. Medications

• Bisphosphonates:

  • Alendronate 70 mg PO weekly

  • Zoledronic acid 5 mg IV yearly

• Denosumab: 60 mg SC every 6 months (max 4 weeks late)

• Teriparatide: 20 mcg SC daily (up to 2 years; follow with bisphosphonate)

• Hormonal Therapy (women):

  • Oestrogen for women <60 years

  • Raloxifene for vertebral fracture risk

Notes:

• Avoid forward flexion in vertebral osteoporosis

• Screen for secondary causes (e.g., malabsorption, medications, endocrine disorders)

MBS Criteria for BMD Testing

• Age >70

• Minimal trauma fracture

• Conditions: Hypogonadism, premature menopause, hyperthyroidism, hyperparathyroidism, coeliac disease, rheumatoid arthritis, CKD, CLD

• Steroids: Prednisolone ≥7.5 mg/day or inhaled budesonide ≥800 mcg/day for ≥4 months

Screening

Risk Factors

• Low activity, BMI <20, smoking, alcohol >2/day (women), >4/day (men)

• Vitamin D <50 nmol/L, recurrent falls

BMD Recommendations

• Men >60, women >50 with risk factors (even if not MBS rebatable)

Exercise Advice

• High-intensity resistance/balance training recommended

Education for Antiresorptive Therapies

Shared Points (Bisphosphonates & Denosumab)

• Risks: Osteonecrosis of jaw (ONJ), hypocalcaemia, fractures while on treatment

• Contraindications: eGFR <30 mL/min

• Monitor vitamin D and calcium before starting therapy

• Repeat BMD 2 years after starting treatment

Bisphosphonates

• Instructions: Take on an empty stomach, 2 hrs apart from calcium/iron/antacids

• Side Effects: Nausea, gastritis, oesophagitis

• Duration: 5–10 years; stop at 5 years if low risk, monitor BMD every 2–3 years after stopping

Denosumab

• Fewer GI side effects vs bisphosphonates

• Requires indefinite treatment or bisphosphonate replacement to avoid rebound fractures

• Adherence critical: Missing doses ↑ vertebral fracture risk

Osteoporosis risk assessment, diagnosis and management flow chart

Osteoporosis and Osteopaenia

T and Z Scores – Levels and Meaning

T Score:

• Normal: > -1

• Osteopaenia: -1 to -2.5

• Osteoporosis: < -2.5

Z Score:

• Compares BMD to same age and sex.

• Z Score < -2 or T Score < -3: Investigate secondary causes.

PBS Criteria for Bisphosphonates/Denosumab

• T Score < -2.5 AND:

  • Age >70 years, or

  • Minimal trauma fracture, even without osteoporosis on BMD.

Monitoring BMD

• Repeat ≥12 months after starting or changing therapy.

False Elevated BMD Readings

• Osteoarthritis of the lumbar spine: Artificially increases spinal T scores.

• Strontium ranelate: Increases BMD due to high atomic weight.

• NB: Use hip T score for more reliable assessment.

When to Investigate for Secondary Causes

• Z Score < -2 or T Score < -3.

• Suspicious history (e.g., fractures without risk factors, young age <50).

• Multiple fractures without clear cause.

Initial Secondary Osteoporosis Investigations

• UEC and CMP: Identify renal failure, hypercalcaemia, Paget’s disease.

• LFTs: Check for chronic liver disease.

• Vitamin D: Deficiency common in osteoporosis.

• TFTs: Exclude hyperthyroidism.

Note:

• Secondary causes include hyperparathyroidism, CKD, malabsorption, or prolonged glucocorticoid use.

• Link findings to fracture history and clinical risk factors for tailored management and referrals.