A tibial stress fracture is a hairline fracture of the tibia bone in the lower leg caused by overuse or repetitive stress.
Symptoms are very similar to ‘shin splints’ with gradual onset pain on the inside of the shin.
On this page:
- Symptoms & diagnosis
- Causes & anatomy
Tibial stress fracture symptoms
Symptoms of a tibial stress fracture are very similar to shin splints (medial tibial stress syndrome) and include pain, usually on the lower third of the inside of the shin that occurs after running long distances. There will be tenderness and possibly swelling over the site of the fracture as well as pain when pressing into (palpating) along the shin bone. A stress fracture may also feel particularly tender at the exact point of injury.
It can be difficult to distinguish a tibial stress fracture from a case of shin splints as an X-ray of the injured leg will often not show any sign of a fracture until the bone has started to heal. If a stress fracture is suspected then another X-ray must be taken 4 weeks after the first and often the new bone can be seen where it has started to heal along the line of the fracture.
Tibial stress fracture causes & anatomy
The lower leg consists of two bones, called the tibia and fibula. The tibia is the larger of the two and its role is load bearing. The fibula is the smaller of the two and its purpose is mainly as an area for muscles to attach. Either of these bones can develop stress fractures. The most common site, however, is two to three inches above the bony bit on the inside of the ankle (called medial malleolus) on the tibia bone.
Long bones such as the tibia have an outer sheath surrounding the hard compact bone called the periosteum with the inner core containing bone marrow. The bone is overloaded through continuous muscle contractions and stress forces of impact when running. In particular, when fatigued, the distribution of the stress forces in the bone is altered because the muscles are unable to take some of the stress or energy so rely more on the bone taking the load. Lots of small impacts on the bone even though they may be very small, a cumulative effect can build up.
The obvious cause of a tibial stress fracture is overuse, however, there are a number of factors which can increase the chances of sustaining a tibial stress fracture. A sudden change in a running surface, for example, going from grass training to lots of track or road running can increase the chances of a stress fracture.
Biomechanical dysfunction of the foot such as overpronation or oversupination can increase the stress on the tibia bone. If the foot overpronates and rolls in, flattening the arch of the foot, this has the effect of rotating the shin bone inwards causing additional torsion or twisting stresses on the bone.
Tibial stress fracture treatment
What can the athlete do about a tibial stress fracture?
If a stress fracture is suspected then a sustained period of rest is needed to allow the injury to begin to heal. Rest for around eight weeks, avoiding weight-bearing exercise especially running. Substitute swimming or cycling if it can be done pain-free or use the opportunity to work on upper body strength in the gym, or technical aspects of your sport if possible. Running in water with a buoyancy aid or belt is also an excellent substitute for running on the road.
A simple taping technique can help reduce the strain on the shin. It works by supporting the muscles of the lower leg, pulling them towards the bone and helping to reduce rotation of the tibia. Just a few strips of 2.5cm non-stretch zinc oxide sports tape applied to the lower leg in a spiral technique can often instantly relieve shin pain. But do not use the tape to resume running if you have a suspected tibial stress fracture.
Exercises to maintain strength and flexibility in the lower leg such as light calf raises as long as they are not painful and wobble balance board training can be done. It is especially important to stretch and strengthen the muscles at the back of the lower leg when returning to weight-bearing exercise. After a period of rest, they may be tight and in poor condition, making the likelihood of sustaining further shin pain from medial tibial stress syndrome (shin splints).
Training methods should be analyzed to try and identify if or how this has contributed to the injury. Does footwear need to be changed? Running shoes should have a life of about 500 miles after which they should be changed.
What can a sports injury specialist or doctor do?
A doctor will x-ray the leg and advise on when it is safe to resume training. Initially, the stress fracture will not show up on an x-ray, however, some signs may be seen after 2 or 3 weeks so it is important to follow up with another x-ray after a period of rest.
Gait analysis can identify any biomechanical problems of the foot which may have increased the chances of injury. Orthotic inserts worn in the shoes can correct foot problems such as overpronation.
Sports massage to the muscles at the back of the lower leg can relax them, releasing any muscle spasm, tight knots, lumps or bumps in the muscle, making them more efficient at absorbing running forces when normal training resumes.