Bone stress injuries (BSIs) are common in distance runners, particularly those training intensely or increasing volume too quickly. Unlike muscle or tendon strains, BSIs often develop silently and can become serious before runners seek help.
What Is a Bone Stress Injury?
A BSI occurs when bones experience repetitive loading without adequate time to repair. This causes micro-damage that, if left unchecked, progresses from a bone stress reaction to a stress fracture—and sometimes a complete fracture (commonly referred to as a ‘broken bone’).
Common BSI sites in runners include:
– Tibia (or the shin)
– Femoral neck (the hip)
– Sacrum (lower back)
– Navicular (a bone in the upper foot)
– Metatarsals (bones in the foot and toes)
Who’s at Risk?
– Runners – Particularly those with or building to high weekly mileage
– Female athletes with low energy availability (RED-S) often seen with inadequate nutrition or large training loads
– Those with poor biomechanics (the way people move) or footwear
– Athletes returning from injury
Early Warning Signs
– Localised bone tenderness
– Pain during or after weight-bearing activity
– Pain that worsens over time
– Aching at night or at rest in more advanced cases
The key difference from “normal” soreness: bone stress pain doesn’t warm up—it often gets worse as the session goes on.
How Do We Diagnose It?
As a bone-focused physiotherapist, I use a combination of clinical tests and load response monitoring. These tests include palpation, strength and power tests, functional tests, site specific tests, and imaging such as MRIs
Different BSI have different levels of management, expected recovery times and treatment pathways. It is important to get an accurate diagnosis to ensure your recovery.
What About Shin Splints?
Shin splints (also known as medial tibial stress syndrome) is a form of BSI affecting the bone lining. It causes diffuse, achy pain along the inner tibia during or after running. Unlike stress fractures, the pain is more generalised and often subsides during rest.
Essentially, it is a very early stage stress reaction of the bone that shares a similar cause: overload and under-recovery.
Treatment Approach
1. Unload the Bone – identify alternative ways to train the body and bone without causing more damage
2. Assess & Address Risk Factors – nutrition, training load, footwear, biomechanics all need to be addressed to optimize recovery
3. Strength & Conditioning – focus on building strength safely in muscles that will help your body absorb force in a way that reduces stress on the bone
4. Return to Load – once we have ticked many of our early clinical goals (relating to pain and ability to perform key tasks/movements), we need to incrementally reintroduce running back into our training.
Case Example
A 19-year-old runner presented with a dull ache in her shin after long runs. MRI confirmed a grade 2 tibial stress reaction. We prescribed two weeks of offloading, strength training, and low-impact cardio. At week 4, she began a return-to-run protocol and was back to full training by week 10—without re-injury.
However, if this runner had not presented to our clinic for assessment, this grade 2 BSI likely would have progressed to a grade 3 BSI. This would have vastly increased her recovery time and hindered her training and progress. The lesson here: It is better to be assessed early and be sure than risk things worsening.
Summary
Bone stress injuries have the potential to completely derail a season or race lead up —but with early diagnosis and structured rehab, runners can return faster and stronger. If your run-related pain is getting worse, not better, it’s time to get your bones checked.
Think that you might have a bone stress injury? Book an Assessment with our clinic today to put the certainty back into your training.
By Riley Anastasi, Physiotherapist & Exercise Scientist at Form & Practice