This page is educational and is not a substitute for professional medical advice, diagnosis, or treatment.
Please ask a qualified health professional about symptoms, treatment decisions, or concerns about your own condition.
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Bones & Joints
Medial tibial stress syndrome (MTSS), commonly known as 'shin splints,' is an overuse injury causing pain along the inside (medial) border of the shin bone (tibia), typically in the lower two-thirds of the leg, resulting from repetitive stress on the bone and surrounding muscles/tendons during running, jumping, or high-impact activities. This is one of the most common running injuries (accounting for 10-15% of all running injuries), developing from accumulated microtrauma to the periosteum (bone lining) and surrounding soft tissues when training volume or intensity increases too rapidly ('too much too soon'). MTSS presents as diffuse, aching pain along the inside shin during activity—initially only during exercise, then progressing to pain before/after exercise if not treated. It differs from stress fractures (focal point tender pain) and compartment syndrome (tight, swollen calf muscles). Treatment focuses on relative rest, addressing training errors and biomechanical factors (pronation, weak hips), with 85-90% resolution in 4-8 weeks with conservative management, though 10-15% develop stress fractures if they continue training through pain.
What it is and why it happens
Medial tibial stress syndrome (MTSS), commonly known as 'shin splints,' is an overuse injury causing pain along the inside (medial) border of the shin bone (tibia), typically in the lower two-thirds of the leg, resulting from repetitive stress on the bone and surrounding muscles/tendons during running, jumping, or high-impact activities. This is one of the most common running injuries (accounting for 10-15% of all running injuries), developing from accumulated microtrauma to the periosteum (bone lining) and surrounding soft tissues when training volume or intensity increases too rapidly ('too much too soon'). MTSS presents as diffuse, aching pain along the inside shin during activity—initially only during exercise, then progressing to pain before/after exercise if not treated. It differs from stress fractures (focal point tender pain) and compartment syndrome (tight, swollen calf muscles). Treatment focuses on relative rest, addressing training errors and biomechanical factors (pronation, weak hips), with 85-90% resolution in 4-8 weeks with conservative management, though 10-15% develop stress fractures if they continue training through pain.