Medial Tibial Stress Syndrome (MTSS) — commonly known as shin splints — describes pain along the inner border of the tibia (shinbone), typically over the lower two-thirds. It is caused by overloading of the bone and its surrounding soft tissue, and is most common in runners, military personnel, and people who have recently increased their training volume.
MTSS sits on a continuum of tibial bone stress that, if unmanaged, can progress to a tibial stress fracture — a more serious injury requiring significant time off activity. This makes early, accurate diagnosis and appropriate load management critical.
Training Load Spike
The most consistent risk factor. Too much, too soon — a rapid increase in running volume, intensity or frequency that the bone cannot adapt to fast enough.
Overpronation & Foot Mechanics
Excessive inward rolling of the foot increases tibial rotation and bending forces with every footstrike, raising cumulative bone stress over a run.
Calf & Hip Weakness
Insufficient strength in the calf and hip stabilisers reduces shock absorption, transferring more impact load directly to the tibia.
Running Surface & Footwear
Hard surfaces and worn or inappropriate footwear reduce cushioning and increase ground reaction forces transmitted to the lower leg.
Gait Pattern
Overstriding, low step rate, and excessive vertical load at initial contact all increase the bending stress on the tibia during running.
Bone Stress Vulnerability
Reduced bone density, nutritional deficiencies and hormonal factors can lower the tibia's capacity to manage repetitive load.
Diffuse aching or sharp pain along the inner shin — typically the lower two-thirds of the tibia
Pain at the start of a run that may ease as you warm up, then returns after
Tenderness to touch along a broad area of the shinbone
Pain that worsens progressively with increasing training load
In more severe cases, pain present at rest or on normal walking
Mild swelling along the shin in some presentations
Diagnosis is primarily clinical. Key features are the location and distribution of tenderness — MTSS produces diffuse tenderness over a wide area, whereas a stress fracture produces point tenderness at a specific spot. We also assess foot mechanics, calf strength, running gait, and training history.
Where a tibial stress fracture cannot be clinically excluded — particularly if pain is localised, severe, or present at rest — we arrange imaging referral. MRI is the gold standard for diagnosing bone stress injuries; plain X-ray is often normal in early stress fractures.
MTSS is primarily a load management problem. Treatment focuses on reducing tibial stress while building the capacity to return to running gradually and safely — not simply resting until symptoms go and repeating the same training pattern.
4 – 6 weeks
Mild MTSS
Early-stage cases with prompt load reduction and biomechanical management can return to running within 4–6 weeks.
6 – 12 weeks
Moderate cases
More established MTSS with significant training history typically requires 6–12 weeks of progressive rehabilitation.
3 – 6 months
Severe or recurring
Chronic or recurrent MTSS — particularly where stress fracture has been excluded — requires a longer, more structured build-back.
If your shin pain has lasted more than 2–3 weeks, is worsening with training, or is present at rest, an assessment is important. MTSS that is managed only with rest and then returned to immediately tends to recur — the underlying biomechanical and load factors must be addressed.
If pain is localised to a single point on the shin, severe, or prevents normal walking, seek assessment urgently — this may indicate a tibial stress fracture requiring imaging and a period of protected weight-bearing.
What is the difference between shin splints and a stress fracture?
MTSS produces diffuse tenderness over a wide area of the inner shin. A stress fracture produces point tenderness at a specific location and is typically more severe — often painful at rest and with normal walking. Both require assessment, but a stress fracture requires imaging to confirm and a period of offloading to heal safely.
Can I keep running with shin splints?
A modified approach is usually possible in mild cases — reducing volume, avoiding hard surfaces, and cross-training with low-impact exercise. Continuing at full training load without addressing the cause almost always leads to worsening symptoms or stress fracture.
Will orthotics help shin splints?
Where overpronation is a contributing factor — which it often is — orthotics can reduce tibial bending forces and form an important part of the management plan. They work best combined with gait retraining and a progressive loading programme.
Why do my shin splints keep coming back?
Recurrent MTSS almost always means the underlying biomechanical factors — overpronation, gait pattern, training load management — haven't been adequately addressed. Rest resolves symptoms temporarily but does not fix the cause. A full assessment is needed to break the cycle.
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We'll identify why your shins keep breaking down and build a plan to get you back running — and keep you there.
