Extensor Tendon Injuries

• EMAIL
• DIGG
• DEL.ICIO.US
• FACEBOOK

For the past two years, I've worked in the medical tent at the Vermont 100 ultra-distance running race and often saw extensor muscle group injuries.

Compartment syndromes, shin splints and stress fractures are all associated with three muscles called the extensor muscle group. The group includes the anterior tibialis, extensor hallicus longus and extensor digitorum longus. They are located at the front of the tibia (shinbone) and originate just below the outside of the knee. They course down the front of the shin and cross toward the body's midline, just above the ankle, and then insert into the foot. The main function of this muscle group is to dorsiflex (bring the toes toward the shin) at toe-off, and to prevent foot drop during the swing phase of the gait. These three muscles and their associated tendons also stop forward motion of the lower leg at heel strike.

The tendons from these muscles lie under the retinaculum, a series of ligaments that cross the lower leg at the ankle. The retinaculum consists of the transverse and cruciate crural ligaments. Overuse and stress injuries to the underlying tendons can occur at this ligametous binding point.

Gravity's role

Every athlete's gravitational forces increase when running, causing the body to act as if it weighs more. Gravity's effect on the extensor muscle group is to increase workloads at heel strike, when the tendons are bound most tightly under the retinaculum and working hardest to brake the forward motion of the lower leg. Tendons traveling under these ligaments can become prone to stress injuries, resulting in sudden-onset tendonitis and associated painful dysfunction.

For the past two years, I've worked in the medical tent at the Vermont 100 ultra-distance running race and often saw extensor muscle group injuries. They are classic overuse injuries. By the halfway mark in the Vermont 100, intense pain from one of these injuries forced many runners to drop out.

Extensor muscle group injuries are not usually seen in shorter distance races, but can be present in hilly, short courses or when runners use hill workouts for training runs. Downhill running is the most aggravating. The tendon sheaths are literally irritated and injured by the rasping grasp of the retinaculum as the ligaments attempt to hold the tendons in place.

I have always believed that increased gravitational forces are the main cause of this problem. As a comparative example, the injury is not often seen in hikers covering long distances and carrying heavy loads. The effect of gravity on the runner can catapult the body's effective weight up to ten and even twelve times normal weight. An efficient runner may be running at two to three times his/her normal body weight, but the inefficient runner is usually above 10 times body weight. Knowing these basic facts, overuse injury becomes easy to understand. The workload is just too great. At heel strike, the body must brake the motion of the lower leg, allowing it to slowly stop moving forward while the foot gradually phases from heel strike to midstance (when it is completely on the ground).

Prevention

Taking the necessary time to allow muscles to develop and become used to an athletic activity is the most important element in injury prevention. Moving forward in a training program should be a gradual process in both time and intensity.

The old rule of not more than a 10 percent increase at a time still prevails, but deserves further explanation. Keep a log that identifies daily workouts. Review and summarize it weekly. Use your past week's mileage totals as the tool for increasing the following week's training schedules. Increase your week's mileage by no more than 10 percent.

Downhill courses can be particularly difficult on this muscle group and should be limited but not eliminated. Add them to your training course gradually. Hill training is important; both uphill and downhill workouts should be part of your training program.

Symptoms and treatment

When the injury occurs, it usually comes on rapidly. Pain will be worse at heel strike or when running downhill. Even walking downhill can be painful. Be smart and STOP; examine the area in the front of your ankle. You may find an area of tenderness when you apply pressure, which can be made worse when you move your foot up or down. Swelling may be present.

RICE: Rest, Ice Compression, Elevation are the treatments of choice for this sudden onset problem. Ice the area in the front of the ankle as soon as possible. An ace bandage may be applied and it should make the condition feel better. Elevate for the first 24 hours as much as possible. Rest is critical. Do not try to run through extensor muscle group injuries or try to return to workouts too soon. Continue to ice three to four times per day for at least 20-minutes each time, keeping your foot elevated at least to the level of your hip. Neoprene compression wraps are very helpful and can be obtained in drug stores and athletic stores. Rest from workouts should continue till there is no stiffness in the ankle. Walking down a flight of stairs is a good test that recovery is complete. If no stiffness is present, you are good to go.

• Login or register to post comments
• 3212 reads
• send to friend