Ankle Pain and Running: What you don’t know can hurt you, Part 1

To enjoy running, remain injury free, and perform at peak levels involves proper training, rest, nutrition, and musculoskeletal health. One musculoskeletal factor is a properly functioning “kinetic chain.” A kinetic chain is the sequence of motion needed to perform an activity. Different activities involve different joints, ligaments and muscles in different ways and thus have different kinetic chains. In running, the kinetic chain involves the core (deep and superficial back and abdominal muscles) and the entire lower extremity, which includes the ankle, along with the foot, knee, and hip/pelvis. When we run, our power comes from the core, as these muscles rotate the spine, creating movement in the hips and then legs to move us forward. For this chain to function properly, the ankle must have normal motion and stability to provide shock absorption, adaptation to changes in terrain, and propulsion, as it must support the weight of the entire body. However, the other areas of this kinetic chain sometimes get more attention and the role of the ankle is sometimes surprisingly forgotten as a cause of injury or decreased performance.

Thus, whenever an athlete is being evaluated for a running injury or is just seeking better performance, the biomechanical function of the ankle joint must be examined. Proper treatment, rehab/strengthening exercises and training then can occur. This article will show how hidden ankle dysfunction can occur, and next month in part two the treatment and exercises will be covered.

Some possible ankle injuries, from the more common to less, are sprained lateral (outer) or medial (inner) ligaments, injury to the tendons crossing the ankle, and even fractures to the talus or calcaneus. The ankle is among the most commonly injured joints in athletics. Cross-country running is one of the sports usually involved, along with basketball, football and soccer. A little anatomy: The talus is the ankle bone, and it sits between the tibia (inner leg bone) and fibula (outer leg bone) and the bones of the foot. The calcaneus is the heel bone, and meets the fibula, talus and foot. Ligaments connect bone to bone, providing stability, and there are two major groups at the ankle. The lateral group connects the fibula to the talus and calcaneus, and the medial group connects the tibia to the talus, calcaneus and the navicular (one of the foot bones). Tendons, which attach muscle to bone, cross the ankle joint and give added stability as well. The peroneal tendons, from the peroneal muscles, are on the outside, the tibialis anterior and toe extensor tendons are in front, the Achilles (from the gastrocnemius and soleus muscles) is in the back, and the tibialis posterior and toe flexor tendons are on the inside. The tendons are held in place as they cross the joint by thin coverings called retinaculum. Finally, there is the joint capsule, a ligament-like tissue that surrounds the joint for some added stability.

When a patient comes in with an acutely sprained ankle or other ankle complaint, ankle involvement is obvious. But sometimes it is not, and it is often the ligaments, capsule, or retinaculum that has hidden problems. For example, often a runner will complain of knee pain or some other injury, and not mention any recent ankle injury when questioned. However, by examining each and every anatomical structure described above, hidden ankle problems can be found. For example there is often tenderness to palpation at key ligaments, indicating something going on with that ankle. Usually the patient then remembers that they once injured the ankle. If they can’t remember the original injury, then they are even more surprised at how sore the tissue is (and let me know it). The original injury could be as far back as a year, or even five or ten years. Why, then, does the ankle remain tender after all that time?

Scar tissue formation in the ligaments or capsule is often to blame for the tenderness. For example, let’s take an ankle sprain, the most common ankle injury. A sprain means you have overstretched some of the fibers that make up the ligament. Swelling may or may not occur, which is why sometimes a light sprain may not seem like that big a deal at all. However, with or without major swelling, the body will attempt to heal the area by laying down new tissue within the ligament- just as a cut will heal. Unfortunately, this “scar” tissue is not as strong, flexible or reactive as the original tissue. Often treatment just addresses the immediate swelling, but the scar tissue remains unless it is treated. This means the “scarred” ligament will not support the joint as well, which leads to abnormal ankle joint motion. Usually there is decreased range of motion when the foot is landing and pushing off. This, in turn, can lead to shortening of the calf and leg muscles. Thus, the function of the leg and then the entire kinetic chain can be affected. Pain and injury can then occur anywhere along the chain- a chronic or re-occurring hamstring strain may be the result, for example, and will not heal fully unless the ankle is checked.

Because it is weaker, less flexible and decreases balance ability, the scar tissue also predisposes the ankle itself to re-injury. With less strength, the scarred ligament has less resistance to overstretching. The decreased range of motion makes the ankle less stable. For the lateral ligament the effect of this limited range of motion is easy to feel: in the calf-stretched position (called ankle dorsiflexion), it is harder to “turn your ankle”, but the ankle turns easily in the toe-down position (called ankle plantarflexion). If you lose calf flexibility, you are more likely to be in the less stable plantarflexion position when you are out there running. Finally, usually your balance will now be worse on the injured side, as the function of the ankle’s proprioceptors is diminished. Proprioceptors are nerve receptors located in the ligaments, joint capsule and muscle tissue. They tell your brain how stretched a muscle is and at what angle a joint is at a given moment, so that the nervous system can alert the muscles to make stride adjustments. The scar tissue decreases the performance of these nerve receptors. In other words, if you hit uneven terrain, you will be more likely to turn your ankle.

In part two of this article, how to treat the scar tissue and restore normal biomechanics of the kinetic chain will be covered.