Osteoporosis Management for the Orthopaedic Surgeon: Closing the Care Gap

Visual Element: An interactive graph showing the "Fracture Cascade" - how a wrist fracture at 50 leads to a vertebral fracture at 60 and a hip fracture at 70, with the associated mortality risk increasing at each step.

Orthopaedic surgeons are technically brilliant. We can nail a femur through a keyhole incision, reconstruct a shattered pelvis, and replace arthritic joints with robotic precision. Yet, we have a blind spot. We are historically terrible at managing the underlying disease that keeps us in business: Osteoporosis.

A patient presenting with a fragility fracture (a fracture resulting from a fall from standing height or less) has established osteoporosis. This is a clinical fact. Yet, studies consistently show that up to 80% of these patients are discharged from our care without any investigation or treatment for their bone health.

This is the "Care Gap." It is our responsibility to close it.

The Scope of the Problem

Osteoporosis is a silent killer.

• The Sentinel Event: A Distal Radius Fracture in a post-menopausal woman is the strongest predictor of a future hip fracture.
• The Mortality: The 1-year mortality of a hip fracture is 20-30%.
• The Re-fracture Rate: Without treatment, the risk of a second major osteoporotic fracture is highest in the first 1-2 years (the "Imminent Risk" period).

Diagnosis: It's Not Just a T-Score

We often rely on the DEXA scan, but we must understand its limitations.

1. DEXA (Dual-Energy X-ray Absorptiometry)

• T-Score: Compares bone density to a healthy 30-year-old.
  • Normal: > -1.0
  • Osteopenia: -1.0 to -2.5
  • Osteoporosis: < -2.5
• Z-Score: Compares bone density to an age-matched control. Useful in younger patients (<50) to screen for secondary causes (e.g., celiac disease, hyperparathyroidism).

2. Clinical Diagnosis

Crucial Concept: If a patient has sustained a low-trauma fracture (hip, spine, humerus, wrist), they have "Clinical Osteoporosis" regardless of their T-score. A patient with a T-score of -1.5 and a hip fracture has osteoporosis and needs treatment.

Pharmacotherapy: The Surgeon's Guide

You don't need to be an endocrinologist, but you need to know the basics to start the conversation or the script.

Class 1: Antiresorptives (The Brakes)

These drugs inhibit osteoclast activity, slowing down bone loss.

Bisphosphonates (Alendronate, Risedronate, Zoledronic Acid)

• Mechanism: Bind to hydroxyapatite crystals. Osteoclasts ingest them and die (apoptosis).
• Administration:
  • Oral: Weekly. Poor absorption (must take on empty stomach, sit upright). High rate of GI side effects.
  • Intravenous (Aclasta/Zometa): Yearly infusion. 100% compliance.
• Timing: Standard teaching was to delay 2 weeks post-fracture to avoid inhibiting callus. However, recent data suggests the clinical benefit of ensuring the infusion happens before discharge outweighs the theoretical risk of delayed union.
• Duration: 3-5 years, followed by a "Drug Holiday" (to reduce risk of atypical fractures).

Denosumab (Prolia)

• Mechanism: Monoclonal antibody against RANK-Ligand. Stops osteoclast formation.
• Administration: Subcutaneous injection every 6 months.
• The Trap: Rebound Phenomenon. If a dose is missed, bone turnover skyrockets, leading to multiple vertebral compression fractures. You cannot just stop Denosumab. You must transition to a bisphosphonate.

Class 2: Anabolic Agents (The Builders)

These drugs stimulate osteoblasts to build new bone. They are reserved for severe osteoporosis (T-score < -3.0 or multiple fractures).

Teriparatide (Forteo)

• Mechanism: Parathyroid Hormone (PTH) analogue. Pulsatile PTH builds bone.
• Administration: Daily self-injection for 18-24 months.
• Contraindication: History of skeletal radiation or Paget's (theoretical osteosarcoma risk).

Romosozumab (Evenity)

• Mechanism: Sclerostin inhibitor. (Releases the "brake" on bone formation).
• Effect: Dual effect (Increases formation AND decreases resorption). Very potent.
• Warning: Small increase in cardiovascular risk. Avoid in recent MI/Stroke.

Establishing a Fracture Liaison Service (FLS)

You cannot do this alone in a busy trauma clinic. The gold standard is the FLS Model.

• The Coordinator: A dedicated nurse who captures every fragility fracture patient (in ED or Ward).
• The Protocol:
  1. Identify.
  2. Investigate (DEXA + Bloods: Calcium, Vit D, PTH, Thyroid, EPG).
  3. Initiate (Start meds or refer to Endo/Geriatrics).
  4. Integrate (Communicate with GP).

Visual Element: FLS Workflow diagram (Identify -> Investigate -> Initiate -> Integrate).

Complications to Consent For

When prescribing, you must mention the rare but famous risks.

1. Osteonecrosis of the Jaw (ONJ): Very rare in osteoporosis doses (1/10,000 - 1/100,000). Higher in cancer patients. Ask about planned dental work.
2. Atypical Femoral Fracture (AFF): Transverse, lateral cortical beak, prodromal thigh pain. Associated with long-term use (>5 years). This is why we have "Drug Holidays."

Conclusion

As surgeons, we must expand our definition of "success." A perfectly nailed hip fracture is a failure if the patient returns 6 months later with a contralateral hip fracture because we ignored their bone density.

Own the bone.

Osteoporosis Treatment Algorithm

Download a decision tree for selecting the right agent based on renal function and severity.