What Is a Stress Fracture?
A stress fracture is a small crack in a bone caused by repetitive force—usually from overuse rather than a single injury. Unlike a traumatic fracture from a fall, stress fractures develop gradually when bone remodeling can't keep up with the load you're putting on it.
Think of it like bending a paperclip back and forth. One bend won't break it, but enough bends will.
Where Do Stress Fractures Happen?
Most Common Sites (Runners)
1. Tibia (shin) - 50% of stress fractures
2. Metatarsals (foot) - 25%
3. Fibula (lower leg)
4. Femur (thigh)
5. Pelvis
6. Navicular (foot) - high-risk
High-Risk vs Low-Risk
High-risk (heal poorly, may need surgery):
Navicular (foot)Fifth metatarsal (outside of foot)Anterior tibiaFemoral neck (hip)Low-risk (usually heal well):
Posterior tibia (most common)Other metatarsalsFibulaPelvisSigns and Symptoms
The Pattern
Pain develops gradually over days to weeksWorse with activity, better with restEventually hurts with walkingMay hurt at rest or at night (later stage)Pain is localized to one spotKey Differences from Shin Splints
Stress fracture:
Pain at one specific pointTender to press on boneHurts with hopping on that legDoesn't warm up and go awayShin splints:
Pain spread over several inchesMay warm up during activityNot as point-tenderRisk Factors
Training Errors
Rapid increase in mileage or intensityNot enough recoverySudden change in surface or shoesToo much high-impact activityNutrition
Low energy availability (not eating enough)Vitamin D deficiencyCalcium deficiencyFemale Athlete Triad / RED-SBiomechanics
High arches or flat feetLeg length discrepancyMuscle weaknessPoor running formOther
Previous stress fractureFemale sexLow bone densityCertain medicationsDiagnosis
Physical Exam
Point tenderness over bonePain with hoppingSwelling sometimes presentImaging
X-ray:
Often negative earlyMay show healing (callus) after 2-3 weeksFirst-line imaging, but limitedMRI:
Gold standardShows stress reaction before fracture visible on x-rayConfirms diagnosisBone scan:
Very sensitiveLess specific than MRIUsed less now that MRI is availableTreatment
Low-Risk Stress Fractures
Rest from impact activities:
No running, jumping, or high-impact sportsWalking allowed if pain-freeTypically 4-8 weeksCross-training:
SwimmingPool runningCycling (if pain-free)Elliptical (sometimes)Gradual return:
When pain-free with daily activitiesWhen bone healed on imaging (if done)Progressive return to running protocolHigh-Risk Stress Fractures
More aggressive treatment:
May need boot or crutchesNon-weight-bearing sometimes requiredLonger rest period (8-12+ weeks)Close follow-up with imagingSurgery sometimes neededReturn to Running
When to Start
Pain-free with daily activities for 10-14 daysNo tenderness at fracture siteCan hop without painUsually 6-8 weeks from diagnosis (low-risk)The Protocol
Week 1:
Walk 30 min, jog 5 minEvery other dayNo painWeek 2:
Walk 5 min, jog 10 min, walk 5 minEvery other dayWeek 3:
Jog 20 min continuousMonitor symptomsWeek 4:
Jog 25-30 minCan run consecutive daysWeek 5-8:
Gradual increase in durationAdd intensity slowlyNo more than 10% increase per weekRed Flags During Return
Stop and consult doctor if:
Pain returns at fracture sitePain with impact activitiesLimpingNight painPrevention
Training Smart
Follow 10% rule (never increase weekly mileage more than 10%)Include rest daysPeriodize training (hard weeks, easy weeks)Don't ignore painNutrition
Eat enough total caloriesAdequate calcium (1000-1300mg daily)Vitamin D (check levels, supplement if needed)Protein for bone and muscle healthStrength Training
Strong muscles protect bonesInclude lower body resistance trainingDon't neglect hip strengthRunning Form
Increase cadence (reduce impact)Avoid overstridingConsider gait analysis if recurring issuesFootwear
Replace shoes every 300-500 milesAppropriate for your foot typeConsider rotation (multiple pairs)After a Stress Fracture
Recurrence Risk
Having one stress fracture increases risk for another. Address:
What training error led to injury?Are there nutritional deficiencies?Do you need different footwear?Is strength training part of your routine?Long-Term
Most stress fractures heal completely with no long-term effects if properly treated. The key is not rushing back and addressing underlying causes.
Stress fractures are frustrating because they take you out of what you love. But trying to run through them makes everything worse. Take the time off, cross-train, address the root causes, and come back gradually. You'll run again—and you'll be smarter about training when you do.