Calcaneal Stress Fracture
An overuse hairline crack in the heel bone
Quick Facts
- Type: Bone (overuse) injury
- Location: Calcaneus (heel bone)
- Common causes: Sudden increases in running or marching
- Hallmark: Heel pain that worsens with activity
Overview
A calcaneal stress fracture is a small crack in the heel bone that develops from repeated impact rather than a single accident. The calcaneus is the largest bone in the foot and bears much of the body's weight during walking and running. When it is loaded repeatedly faster than it can repair itself, tiny cracks form.
Stress fractures are common in runners, military recruits, and others who suddenly increase their activity. Pain comes on gradually and worsens with use, which sets it apart from a fracture caused by a fall. Because the symptoms can resemble plantar fasciitis or heel fat pad syndrome, accurate diagnosis is important so the bone can heal properly.
Symptoms
The main symptom is heel pain that builds over days to weeks and worsens with weight-bearing.
- Deep, aching heel pain that worsens with walking, running, or standing
- Pain that eases with rest, at least early on
- Tenderness when the sides of the heel are squeezed
- Swelling around the heel
- A limp or change in walking pattern to avoid pressure
As the fracture progresses, pain may occur even at rest. Unlike a heel bruise or plantar fasciitis, squeezing both sides of the heel bone together often reproduces the pain.
Causes
Stress fractures result from repeated loading that outpaces the bone's ability to repair. Common triggers include:
- Sudden increases in activity: Quickly ramping up running distance, intensity, or marching.
- Repetitive impact: Long-distance running, jumping sports, or prolonged standing on hard surfaces.
- Inadequate footwear: Worn-out or unsupportive shoes that fail to absorb impact.
- Weakened bone: Low bone density makes the calcaneus more prone to cracking under normal loads.
Poor nutrition, low energy availability, and certain hormonal conditions can also reduce bone strength and raise the risk.
Risk Factors
- Sudden increases in training volume or intensity
- Running and high-impact sports
- Military training and prolonged marching
- Low bone density or osteoporosis
- Poor nutrition or low vitamin D and calcium intake
- Female athlete triad (disordered eating, menstrual irregularity, low bone density)
- Worn or unsupportive footwear
Diagnosis
Diagnosis combines the history of gradually worsening activity-related heel pain with a physical exam and imaging.
- Physical exam: Squeezing the heel bone from both sides typically reproduces the pain.
- X-rays: Often normal early on, since stress fractures can take weeks to become visible.
- MRI or bone scan: More sensitive tests that can detect a stress fracture before it shows on X-ray.
If early X-rays are normal but suspicion is high, the clinician may treat for a stress fracture or order advanced imaging.
Treatment
The cornerstone of treatment is rest from the activity that caused the injury so the bone can heal.
- Reduced weight-bearing: Cutting back on running and impact, sometimes using a walking boot or crutches to offload the heel.
- Relative rest: Switching to low-impact activities like swimming or cycling while the bone heals.
- Ice and pain relief: Icing and over-the-counter pain medicine as directed for comfort.
- Gradual return: Slowly rebuilding activity once pain has resolved, to avoid re-injury.
- Addressing the cause: Correcting footwear, training errors, and any nutritional or bone-density problems.
Most calcaneal stress fractures heal within about 6 to 8 weeks with appropriate rest. Severe or displaced fractures are uncommon but may need further evaluation.
Prevention
- Increase running distance and intensity gradually (no more than modest weekly jumps)
- Wear supportive, well-cushioned shoes and replace them regularly
- Cross-train with low-impact activities to vary the load on bones
- Eat a balanced diet with adequate calcium and vitamin D
- Allow recovery days between hard training sessions
- Address menstrual irregularities and low bone density with a clinician
When to See a Doctor
See a clinician for heel pain that worsens with activity and does not improve with a few days of rest, or for pain that returns each time you resume exercise. Seek prompt care if you have:
- Heel pain that occurs even at rest or wakes you at night
- Inability to put weight on the foot
- Significant swelling, bruising, or deformity
- Pain after a fall from height, which can cause a more serious heel fracture
Frequently Asked Questions
How long does a calcaneal stress fracture take to heal?
Most heel stress fractures heal in about 6 to 8 weeks with rest from impact activity. Returning to running too soon can slow healing or cause the fracture to recur, so it is important to rebuild activity gradually once pain is gone.
Can I still walk with a calcaneal stress fracture?
You may be able to walk with mild pain, but continuing high-impact activity can worsen the crack. Treatment usually involves reducing weight-bearing, sometimes with a walking boot, and avoiding running until the bone heals.
How is a stress fracture different from plantar fasciitis?
A stress fracture causes deep heel pain that worsens with activity and is reproduced by squeezing the sides of the heel bone. Plantar fasciitis usually causes sharp pain in the inner heel and arch that is worst with the first steps in the morning. Imaging can help confirm the difference.
Will an X-ray show a calcaneal stress fracture?
Not always, especially in the first few weeks, because early stress fractures may not appear on X-ray. If symptoms strongly suggest a fracture but the X-ray is normal, an MRI or bone scan can detect it earlier.
How can I prevent a heel stress fracture?
Increase training gradually, wear supportive cushioned shoes, cross-train to vary impact, and ensure adequate calcium and vitamin D. Addressing low bone density and giving bones rest between hard sessions also lowers the risk.
References
- American Academy of Orthopaedic Surgeons (AAOS). Stress Fractures.
- Mayo Clinic. Stress fractures — Symptoms and causes.
- MedlinePlus, U.S. National Library of Medicine. Stress fractures.