Calcaneal Stress Fracture
CIM Case: Calcaneal Stress Fracture
Clinical Scenario
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:
- Point tenderness over the medial and plantar aspect of the calcaneus
- Positive calcaneal squeeze test
- No visible swelling or bruising
- Full range of ankle and subtalar motion
- Normal gait when walking, antalgic when jogging
- No signs of hyperpronation or cavovarus foot
- Neurovascularly intact
Investigations Provided
Laboratory Results
| 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 |
Imaging
Image 1: Weight-bearing Lateral Foot Radiograph
Radiological features:
- Normal calcaneal trabecular pattern
- No visible fracture line
- No periosteal reaction
- No sclerosis
- Normal Bohler's angle (28°)
- No degenerative changes at subtalar joint
Image 2: MRI Left Foot (T1 and STIR sequences)
MRI findings:
- Linear hypointense line within the posterior calcaneal tuberosity on T1
- Extensive surrounding bone marrow oedema on STIR
- No complete cortical breach
- Oedema extends from medial to lateral tuberosity
- No soft tissue mass or fluid collection
- Plantar fascia normal
- Achilles tendon normal
Questions & Model Answers
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?
Key Teaching Points
Pattern Recognition
This pattern suggests Calcaneal Stress Fracture:
- Endurance athlete with high training volume
- Insidious onset heel pain worse with exercise
- Positive calcaneal squeeze test
- Normal X-ray in early presentation
- MRI shows bone oedema and fracture line
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 |
Critical Management Points
- Normal X-ray does NOT exclude stress fracture - MRI is gold standard
- Grade severity using MRI - guides treatment duration
- Protected weight bearing for Grade 4 - 6-8 weeks
- Address metabolic factors - Vitamin D, calcium, energy availability
- Gradual return to sport - 10% rule
- Prevention is key - address training errors and risk factors
Common Examiner Follow-ups
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:
- Multidisciplinary team (sports medicine, dietitian, psychologist)
- Increase energy availability
- May require reduced training load
- Endocrinology referral for severe cases
- DEXA scan mandatory
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:
- Non-union despite 6+ months conservative treatment
- Complete displaced fracture
- High-level athlete with time-sensitive return requirements (controversial)
Most calcaneal stress fractures heal with conservative management.
Related Topics
- Navicular Stress Fracture
- 5th Metatarsal Stress Fractures (Jones Fracture)
- Female Athlete Triad / RED-S
- Plantar Fasciitis
- Bone Stress Injury Continuum
- Vitamin D and Bone Health