Medial Tibial Stress Syndrome (MTSS) is often referred to as shin splints which is a catch all term for pain in the distal one half to one third of the shin, localized along the inside(medial) border of the tibia. MTSS is an overuse syndrome that is often the result of repetitive running or jumping. In fact it is accounted for 10 to 15 percent of all running injuries, and up to 60 percent of all conditions that cause pain in athlete’s legs. Not everyone who likes to run or jump is at risk for this injury. There are certain risk factors that make one more prone to developing MTSS. The risk factors that are more controllable include: weakness of lower leg muscles, shoes that provide little support or cushioning, inadequate calcium intake, increased muscular strength of the plantar flexors, and training errors such as training on hard, uneven, or inclined surfaces and overtraining. Risk factors that are a little less controllable but still manageable include: malalignment problems such as a varus foot, tight heel cord, hypermobile pronated foot, or a forefoot supination, and previous injury to the structures involved.
Some studies indicate that the rate of pronation and the timing of pronation are more significant risk factors than pronation alone. If pronation is excessive or occurs too quickly or at the wrong time then greater tensile loads will be placed on the muscle-tendon units that assist in controlling this complex tri-planar movement. Pronation occurs in order to get the forefoot in contact with the ground for push off. Sprinters may present with similar symptoms but with a different cause, that being overuse of the plantar flexors secondary to being on their toes during their event. Anatomic evidence suggests that the soleus and the flexor digitorum longus are the two muscles involved, posterior tibialis has been ruled out because it does not have any medial tibial attachments.
There are several suggested treatments and prevention plans available, however they do not work for everyone and none of them are guaranteed. Treatment plans include: increase strength (especially eccentric) in soleus muscle, control overpronation by use of orthotics and exercises, promote adequate shock absorption via insoles, new shoes, maintenance of proper foot biomechanics, and work with coaches to commit at least one day per week for a pool work out or some other type of non-weight bearing cardio exercise to allow tibial unloading and for proper bone remodeling response. Shoes for a pronated runner should not exceed 500 miles, and should be specifically designed to prevent the arch in the foot from falling too much and/or too quickly. Ideally athletes should not return to full play until there is minimal to no pain upon palpation, all causes of excessive pronation have been addressed with an orthotic and proper shoe wear, there is sufficient gastrocnemius-soleus musculature flexibility, and when the athlete has completed the gradual running progression and a sport-specific functional progression without an increase in symptoms. MTSS can lead to a tibial stress fracture if symptoms continue to worsen without treatment. As with all injuries, it is important to communicate effectively with your athletic trainer and team physician about the severity and timing of symptoms.
Suggested exercises for pronation correction:
Lying on Back
- Curl the toes downward, and hold while pulling the foot upward and inward
- With legs straight and together, try to touch the soles of the feet together
Sitting on Chair
- With left knee crossed over right, move left foot in a half-circle downward, inward, and upward, and then relax. (do not turn the foot outward.) Repeat with the right foot
- With the knees apart, place the soles of the fee together and hold while bringing the knees together
- Place a towel on the floor. With the feet parallel and approximately 6 inches apart, grip the towel with the toes, and pull inward (in adduction) with both feet, bunching the towel between the feet
- With a small ball (~1 ¼ to 1 ½ inches in diameter) cut in half and placed under anterior arch of the foot, grip the toes downward over the ball
- With the feet straight ahead or slightly out-toeing, roll weight to the outer borders of the feet by pulling upward under the arches.
- Walk along a straight line on the floor, pointing the toes straight ahead and transferring weight from the heel along the outer border of the foot to the toes.
Kendall, F. P., McCreary, E. K., Povance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function with posture and pain. (5 ed., p. 446). Baltimore: Lippincott williams & Wilkins.
Prentice, W. E. (2004). rehabilitation techniques for sports medicine and athletic training. (4 ed., pp. 597-598). New York: McGraw-Hill.
Craig, D. I. (2008). Medial tibial stress syndrome: Evidence-based prevention. 43(3), 316-318.
Beck, B. R., & Osternig, L. R. (1994). Medial tibial stress syndrome. the location of muscles in the leg in relation to symptoms. 76, 1057-1061.