Shin Splints (Medial Tibial Stress Syndrome)

What shin splints are

With every footstrike, the tibia bends slightly, and the muscles that attach along its inner border pull on the bone's outer lining (periosteum). When the load is higher than the bone can adapt to, usually because training has increased too fast, the bone and its lining become irritated and painful. Shin splints sit at the mild end of a spectrum of bone stress injury. If loading continues, it can progress to a stress fracture.

Shin splints symptoms

• Dull, aching or sharp pain along the lower two-thirds of the inner shin
• Tenderness over a stretch of bone 5 cm (2 inches) or longer
• Pain at the start of exercise that may ease during the run, then return afterward or the next morning
• Mild swelling in some cases
• Both legs often affected

In early stages pain stops when exercise stops. As it worsens, pain can last throughout the run and into daily activity.

Causes and risk factors

• Training errors: too much, too soon, too fast, especially in the first weeks of a new program
• Hard or uneven surfaces, and hill running
• Worn-out or unsuitable shoes
• Foot mechanics: flat feet and excessive pronation; high, rigid arches
• Weak calf, hip and core muscles, and tight calves
• Female sex, previous shin splints, higher body weight, and low bone density
• Low energy availability: not eating enough for the amount of training, which can disrupt hormones and periods and weaken bone
• Low vitamin D (vitamin D deficiency)

Shin splints vs stress fracture vs compartment syndrome

Acute compartment syndrome, usually after a fracture or crush injury, is a surgical emergency.

Diagnosis

A doctor or physical therapist asks about recent training changes, feels along the shin, checks for focal tenderness, and may ask you to hop on one leg. They look at your footwear, foot posture and running pattern. X-rays are usually normal and are not needed for typical shin splints. MRI is the best test when a stress fracture is suspected.

How to treat shin splints

Relative rest (2 to 4 weeks)

• Stop or sharply reduce running and jumping
• Keep fit with low-impact activities: swimming, pool running, cycling or the elliptical
• Walk normally if it is pain-free

Pain relief

• Ice packs for 15 to 20 minutes after activity, a few times a day
• Acetaminophen (paracetamol) or an NSAID such as ibuprofen at the label dose for short-term relief, if safe for you
• Gentle massage of the calf muscles

Exercises

• Calf raises: double-leg, then single-leg, and on a step, building to 3 sets of 15
• Toe raises and heel walking to strengthen the front of the shin
• Calf and soleus stretches (straight and bent knee)
• Hip and core strengthening: clamshells, side planks, glute bridges
• Balance work on one leg

Footwear and form

• Replace running shoes every 500 to 800 km (300 to 500 miles)
• Choose shoes suited to your feet. Over-the-counter arch supports may help if you have flat feet
• Increase running cadence slightly and avoid overstriding

Returning to running

1. Wait until you are pain-free with walking, hopping and daily activity, and the shin is no longer tender.
2. Start with short walk-run intervals on soft, flat surfaces every other day.
3. Build up by no more than about 10% per week.
4. Pain during or after a run means scale back for a few days.
5. Add hills, speed and hard surfaces last.

Prevention

• Increase training gradually and include rest days
• Mix surfaces and activities
• Strength-train the calves and hips twice a week
• Eat enough to match your training, with adequate calcium and vitamin D
• Women with missed periods while training hard should see a doctor, since this raises bone stress injury risk

How long do shin splints last?

Mild shin splints often settle in 2 to 3 weeks of reduced activity, and most cases resolve within 6 weeks. Severe or long-standing shin splints can take 3 months or more. Returning to full training too soon is the main reason they come back.

Frequently asked questions

What causes shin splints?

Shin splints are caused by repeated stress on the shin bone and its muscle attachments, usually from increasing running or jumping too quickly. Hard surfaces, worn shoes, flat feet, weak calf and hip muscles, low bone density and not eating enough for your training level all raise the risk.

Can you run with shin splints?

Light running may be possible if the pain is mild, eases during the run, and is not worse the next day. If pain persists during the run, makes you limp, or is getting worse, stop running and cross-train for 2 to 4 weeks to avoid a stress fracture.

How do I know if it's a stress fracture or shin splints?

Shin splints cause diffuse tenderness along several inches of the inner shin. A stress fracture usually causes sharp pain at one specific spot, pain when hopping, and pain at rest or at night. If you suspect a stress fracture, stop running and see a doctor, who may order an MRI.

Should I ice or heat shin splints?

Ice is more useful in the first days and after activity, applied for 15 to 20 minutes with a cloth between the ice and skin. Gentle heat or massage on tight calf muscles before exercise can feel good later in recovery. Neither replaces rest from impact and strengthening.

Do compression sleeves help shin splints?

Compression sleeves may make the legs feel more comfortable and reduce soreness for some runners, but there is little evidence they prevent or cure shin splints. Training load management, strengthening and appropriate footwear are far more important.