A tibia stress fracture is a hariline fracture of the tibia caused by overuse or repetitive stress. Symptoms are very similar to 'shin splints' with gradual onset pain on the inside of the shin.
Tibia stress fracture symptoms
Symptoms of a tibial stress fracture include pain, usually on the lower third of the tibia that occurs after running long distances. There will be tenderness and possibly swell over the site of the fracture as well as pain when you press into the shin. An X-ray of the injured leg will often not show any sign of a fracture. 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.
Causes & anatomy
The two bones of the lower leg are 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 role is mainly for muscle attachment. Either of these bones can have stress fractures. The most common site, however, is two to three inches above the bony bit on the inside of the ankle (medial malleolus) on the tibia bone.
Causes include overloading the bone by continuous muscle contractions for example in running. Stress distribution in the bone altered because of continuing to run when the muscles are particularly fatigued. Muscles are unable to take some of the stress so rely more on the bone.
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 tibia stress fracture. Lots of small impacts on the bone even though they may be very small, a cumulative effect can build up.
Tibia stress fracture treatment
What can the athlete do about a stress fracture?
Rest for around eight weeks. Avoid 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. Running in water with a buoyancy aid or belt is also an excellent substitute for running on the road.
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.
Training methods should be analyzed to try and identify if or how this has contributed to the injury. Does footwear need to be changed?
What can a sports injury specialist or doctor do?
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.
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 motion.