Patient: 29-year-old male competitive runner Presentation: 6-week history of insidious onset left heel pain, worse with continuous exercise, improving with rest Relevant history: Marathon training, increased running volume from 30km to 50km per week over past 3 months, no history of trauma Exercise pattern: Runs 6 days per week, minimal cross-training, recently transitioned to minimalist footwear Examination findings:
| Test | Result | Normal Range | Interpretation |
|---|---|---|---|
| Vitamin D | 38 nmol/L | 50-150 nmol/L | Low - insufficiency |
| Calcium | 2.35 mmol/L | 2.15-2.55 mmol/L | Normal |
| Phosphate | 1.1 mmol/L | 0.8-1.5 mmol/L | Normal |
| PTH | 5.2 pmol/L | 1.6-6.9 pmol/L | Normal |
| TSH | 1.8 mU/L | 0.4-4.0 mU/L | Normal |
Image 1: Weight-bearing Lateral Foot Radiograph
Radiological features:
Image 2: MRI Left Foot (T1 and STIR sequences)
MRI findings:
What is the likely diagnosis and what clinical features support this?
Why is the X-ray normal and what imaging modality is best for diagnosis?
What are the risk factors for stress fractures and how do you assess for underlying metabolic issues?
What is your management plan for this Grade 4 calcaneal stress fracture?
What is the differential diagnosis for heel pain in a runner?
What is the prognosis for return to sport and how do you prevent recurrence?
This pattern suggests Calcaneal Stress Fracture:
Comparison - Stress Fracture vs Plantar Fasciitis:
| Feature | Stress Fracture | Plantar Fasciitis |
|---|---|---|
| Pain pattern | Activity-related | First-step morning pain |
| Squeeze test | Positive | Negative |
| Windlass test | Negative | Positive |
| Tenderness | Posterior/medial tuberosity | Medial tubercle |
| MRI | Bone marrow oedema | Fascial thickening |
Q: "What if this was a female athlete with amenorrhea?"
This would suggest Relative Energy Deficiency in Sport (RED-S), formerly known as Female Athlete Triad:
| Component | Features |
|---|---|
| Low energy availability | Inadequate caloric intake for exercise expenditure |
| Menstrual dysfunction | Amenorrhea or oligomenorrhea |
| Low bone density | Z-score ≤-2.0 |
Management:
Q: "What are high-risk vs low-risk stress fracture sites?"
| High-Risk Sites | Low-Risk Sites |
|---|---|
| Femoral neck (tension side) | Calcaneus |
| Anterior tibial cortex | Posterior tibial cortex |
| Navicular | Fibula |
| 5th metatarsal base (Jones) | 2nd-4th metatarsal shafts |
| Talus | Pubic rami |
| Patella | Sacrum |
High-risk sites require more aggressive treatment (often non-weight bearing, sometimes surgery) due to risk of complete fracture, delayed union, or non-union.
Q: "When would you consider surgical intervention for a calcaneal stress fracture?"
Surgical intervention is rarely indicated but may be considered for:
Most calcaneal stress fractures heal with conservative management.