How to Prevent Marathon Injuries, Part 3

PART 3

Welcome to Part Three of our three part series on common running injuries, injury prevention and treatment. The following article discusses stress fractures that commonly occur in the lower extremity; more specifically the shin (tibia) and foot. As noted in the last article on ankle injuries the lower extremity experiences forces of between 9 and 13 times one’s body weight during running, so if the body is not properly cared for, in terms of hydration and nutrition, and is not properly equipped, in terms of proper running shoes, stress fractures may appear.

NOTE ON STRESS FRACTURES IN RUNNERS:

  • With the upcoming NYC marathon approaching and mileage increasing, the incidence of stress fractures is becoming more common in our practice.
  • Stress reactions and stress fractures are similar pathological entities with a stress reaction being a radiological diagnosis and a stress fracture being a progression of that to a true fracture through bone.
  • They typically occur in the tibia and in the lesser metatarsals as the result of an overuse injury.
  • Under normal circumstances, bone is being constantly broken down and rebuilt.  The rate at which it is being rebuilt depends on mechanical load and also the metabolic supply of calcium, vitamin D and other nutrients.  (Importance of proper diet and nutrition!)
  • In runners, there is a constant repetitive loading, and the areas that are most vulnerable are the tibia in pronators and the fibula in supinators.  Stress fractures can also occur in the foot, along the metatarsal bones.
  • The treatment is based on two factors, altering the mechanical input and also addressing the biological or metabolic aspect.
    • Mechanical input is treated with orthotics, physical therapy, and reducing the intensity of training.
      • Supinator:
        • Requires a lateral heel wedge orthotic
      • Pronator:
        • Requires a medial heel wedge orthotic
    • Metabolic profile is utilized to evaluate a patient’s dietary vitamin C, vitamin D and calcium intake, compared with their metabolic demand as they increase their intensity, duration, speed and distance.
  • As for physical therapy, with the introduction of the Alter-G, runners can now get back and prevent deconditioning.
    • The Alter-G is a gait simulator which can vary the amount of weight transfer to the foot simulating antigravity.
    • In doing so, it allows the patient to maintain muscle tone and stamina while unloading the bone itself to varying degrees to allow time for healing.
  • Additionally, shockwave is becoming increasingly available in physical therapy and doctor’s offices.
    • Shockwave stimulates the blood supply, increases growth factors and reduces pain receptors in and around a stress fracture, to stimulate early regeneration and repair.
    • Shockwave is usually performed two to three times over a month and is relatively non-painful.
  • Most patients who have stress fractures will take four to six weeks before they will get back to their previous running intensity.  Prevention is key here. Using the correct sneaker with an appropriate orthotic for the foot shape and maintaining a runner’s metabolic profile, are both exceedingly important for marathoners.

Treatment of Stress Reactions

There are many different schools of thought about treating stress fractures in the sports medicine world. I believe if you continue to run on a small fracture, it will eventually develop into a full fracture, which will effectively put you on the sideline for eight to 10 weeks.

When diagnosing and treating tibial, or any other stress reaction for that matter, it is important to identify a possible stress reaction as soon as possible, and realize that everybody recovers differently. This becomes especially important when dealing with the lower leg because of the difficulty in differentiating between a stress fracture, or hairline fracture of the tibia, and a shin splint or pulling away of the muscle from its attachment to the tibia. Therefore, it is a good idea to stop activity and see a healthcare professional as soon as shin pain is felt.

With shin splints and stress fractures in the lower leg, it is also important to remember that rest may not only mean taking a break from running. The standing and walking we do to complete normal, daily activities can often be too much for a bone that has been stressed. It may also be necessary to put the athlete in a walking boot, air cast or full lower leg air cast for four to eight weeks, and up to 16-20 weeks if the injury progresses to a full fracture.

Whether the injury requires immobilization or not, it is important that the athlete be pain free prior to beginning any type of strengthening or aerobic activity. Once pain free, phase one of recovery is to restore range of motion. The ankle joint must have full range of motion before functional training can begin. In addition, good flexibility of the lower leg muscles will help long-term by allowing for more shock absorption in the lower extremity during running and training.

Recommended Exercises:

  • Ankle ABC’s: Write the ABCs in the air with your big toe.
  • Towel Stretch of the Calf and Achilles Tendon: While sitting upright, place a towel around the toes and pull them up toward the shin.

Phase two, which can coincides with phase one, is to begin low-level, low-impact strengthening. This might include four-way ankle exercises for the shin, ankle and foot muscles, including the gastroc-soleus complex and anterior tibialis.

Recommended Exercises:

  • Four Way Ankle Strengthening: Using Theraband as resistance, complete the following four motions: pull toes towards head, press toes down, pull toes away from body midline and pull toes towards body midline.
  • Calf raises: Standing with support, flex the calves and rise up off the heels.
  • Toe Raises: Standing with support, flex the front of the shin and rise up off the toes.

Finally, phase three of rehab will progress the athlete into functional and full weight-bearing activities. As with any injury, there is no direct route from the treatment table back to the pavement. A runner must recover their general fitness and then gradually progress to a full return to activity.