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Corrective Exercise - Part 1: The Foot, Ankle and Knee


This is the first article in a three part series that will familiarize trainers with the functional anatomy of the major structures of the body and explain the most common musculoskeletal imbalances for each. Trainers will learn how to assess a client’s imbalances as well as some techniques that can be used during regular exercise programs to correct problems, eliminate pain and improve function.

About the Feet and Ankles

The feet and ankles act as shock absorbers when the body interacts with a contact surface. They also help the body adapt to the terrain (i.e., the ground) via side to side movement.

The ankle can be broken down into two parts: the true ankle joint and the subtalar joint. The true ankle joint is the joint immediately below the tibia and fibula and functions as a shock absorber. The talus bone is located just below the true ankle joint and above the heel bone. There is a joint just below the talus bone called the subtalar joint. This joint helps displace force from side to side (see Figure 1).

Figure 1

The foot consists of three parts: the hindfoot, the midfoot and the forefoot. The hindfoot (talus and heel bone) acts to absorb shock and displace it forward and from side to side. The midfoot (small bones in the foot between the heel and the toes) helps continue dissipating force from side to side. The forefoot (toes) adapts further to the terrain and aids with propulsion during gait (see Figure 1).

The most common deviations found in the feet and ankles are overpronation and lack of dorsal flexion. Pronation is a necessary function of the foot. It is needed to help transfer forces forward and towards the midline of the body. During pronation, the medial arch flattens and the heel rolls inward. Overpronation, however, is when the foot collapses too much or too quickly. Overpronation can affect the correct function of the entire kinetic chain.

Dorsal flexion is a normal function of the foot and ankle that involves pulling the foot back towards the shin. It enables us to maintain alignment throughout the body. The ability to dorsal flex can be limited as a result of overpronation. This is due to the excessive stress overpronation places on the foot, ankle and calves. Limited dorsal flexion impairs all weight bearing activities from standing to squatting to walking and running.

About the Knees

The primary function of the knee is to link the upper and lower leg by way of a hinge joint. Although the knee does have capabilities for movement in all three planes, its main function is flexion and extension.

The knee cap (patella) attaches to the quadriceps above the knee via the quadriceps tendon and to the tibia below the knee by way of the patella ligament. Correct alignment of the femur and tibia ensures the patella moves smoothly during flexion and extension. There are two shock absorbers between the femur and tibia (medial and lateral meniscus). On either side of the knee are two ligaments (medial and lateral collateral ligament) that give side to side support to the knee. Inside the knee between the tibia and femur lies the Anterior Cruciate Ligament

(ACL) and Posterior Cruciate Ligament (PCL), which help stabilize the knee from front to back (see Figure 2).

Figure 2

The most common deviation of the knee is problems with side to side alignment. Side to side alignment refers to the position of the knee in relation to the femur above and the tibia below. If the knee has side to side alignment problems, the patella will not move freely over the femoral grove when the knee flexes and extends. The resultant tracking problems can cause the joint to become irritated.

Assessing the Feet and Ankles 

In order to assess the feet, ankles and knees, you must be able to see and feel these structures clearly. Ask your client to remove her shoes and socks during the assessment and wear shorts, if possible.

To evaluate whether the foot is overpronated, look to see if the arch is dropped or absent and/or if the soft tissue of the fallen arch bulges out on the inside of the foot (see Figure 3).

Figure 3

Teaching Neutral Foot and Ankle Position

If a client overpronates, you must teach her how to find a neutral position for the foot and ankle. There are two small indentations at the base of the ankle just below the ankle joint. Place your thumb on the dimple on the inside of the ankle and your forefinger on the dimple on the outside (see Figure 4). Ask your client to roll her foot and ankle inward (overpronate). You will feel pressure on your thumb. Ask her to roll outward (oversupinate), and you will feel pressure on your forefinger. This pressure is the talus bone moving in the ankle. Coach your client to pronate and supinate until you feel even pressure of the talus bone on both your thumb and forefinger. This is the anatomical neutral position for the foot and ankle. Most people will have to supinate to get to neutral from their dysfunctional overpronated position.

Figure 4

Relationship Between the Feet, Ankles and Knees

While your client is in a neutral foot and ankle position, look at her knees. The center of the knee cap will now likely be in line with the second toe (its anatomical neutral position). When relaxing from neutral, most clients will fall back into an overpronated position. Notice that the tibia and femur will rotate inward with the foot. This rotation will cause the knee to rotate inward and subsequently be out of alignment.

When the knee shifts towards the middle of the body, a person may turn her foot outward to keep the knee pointing forward. This compensation places further stress on the foot as forces can no longer pass over all the toes when walking. This can lead to calluses on the inside of the big toe and/or bunions. It can also place undue stress on the underside of the foot. Since overpronation also causes the heel to roll inward, the calf muscle (which attaches to the heel) may no longer function optimally, creating an imbalance in the lower leg and ultimately preventing the foot from dorsiflexing.

When your client transfers weight when she walks, squats or lunges, she must pronate to help dissipate force. The key is to assess whether she overpronates (or can not slow forces down into pronation with her muscles), thereby placing undue stress on the joint(s).

Assessing the Knees 

To evaluate whether your client has side to side alignment issues, ask her to stand on one leg and bend her knee to about 20 to 30 degrees for three to four times. Watch the center of her knee. Note whether the knee moved inward (or away from) the center line of the body (see Figure 5).

Figure 5

Relationship Between the Knees, Feet and Ankles

If your client’s knee cap moved towards the midline of her body during the assessment for side to side alignment, it is likely that her foot and ankle overpronated as well. This overpronation causes the lower and upper leg to inwardly rotate, which adds further stress to the knee.

It is natural for there to be some movement of the knee towards the midline of the body when your client squats and transfers weight forward. The key is to watch for coordinated motion between the ankle and knee. For instance, if the foot collapses and the knee juts inwards during the squat, there is probably a weakness that needs to be addressed.

Exercise Recommendations

Squats, single leg squats, leg press, lunges, the elliptical machine and running all involve ankle and knee flexion. If the foot overpronates during these activities, the knee joint can not function optimally. Similarly, if the knee moves excessively towards the midline of the body, the foot will overpronate, which will limit dorsiflexion. These structural malalignments can cause foot problems like plantar fasciitis, bunions and shin splints. They can also cause both medial and lateral knee conditions such as IT band pain, chrondromalacia and ligament irritation.

Here are three exercises to help your clients overcome the structural deviations discussed herein.

  1. Golf Ball Roll (with active stretch of underside of foot) - Overpronation leads to wear and tear of the plantar fascia and degeneration of structures on the underside of the foot. The golf ball roll is a myofascial massage technique that can help your clients regenerate the tissue on the underside of their feet and prevent painful micro-tears of the plantar fascia. Have your clients roll a golf ball daily on the underside of each foot for 30 seconds to one minute on any sore spots (see Figure 6). Also ask your clients to roll out their feet before each workout. As they roll the ball, coach them to pull their toes towards their shins. This active stretch will result in a release on the flexor muscles on the underside of the foot, which can effectively release tension and help realign the structures.
  2. Figure 6
  3. Big Toe Pushdowns - When people overpronate, the arch of the foot becomes weak and can no longer help dissipate force. The flexor hallicus muscle, which passes under the foot and helps push down the big toe, also helps maintain the arch of the foot. You will notice that the big toe of chronic overpronaters may be bent inwards towards the lesser toes. This is usually because these people no longer use the big toe to push down and it has now become weak. Have your client find a neutral foot and ankle position (see Figure 4). Have them maintain this position and instruct them to push their big toe down without collapsing at the ankle or foot. As they get stronger, they will feel the muscle contract under the arch of the foot. You can coach your clients to activate this muscle to help them in all weight bearing exercises.
  4. Calf Stretch (with activation of tibialis anterior) - Overpronation is usually accompanied by lack of dorsal flexion and tight calf muscles. This is because the calf muscle attaches to the heel by way of the Achilles tendon. Therefore, when the foot overpronates, the heel moves towards the midline of the body (everts) and the calf muscles can get irritated. Performing a calf stretch in a neutral foot position (see Figure 4) while activating the muscles that pull the foot up (dorsiflexion) can help to realign the calf muscles, the foot and strengthen muscles that may be weak at the front of the shin (e.g., tibialis anterior). Instruct your clients to place one foot behind them and push the heel of that foot into the ground (see Figure 7). Watch for overpronation during the stretch and coach clients into a neutral position in the foot and ankle, if needed. As they perform the stretch, ask them to try to pull their foot and toes towards their shin. Hold for 30 seconds on each side.
Figure 7

Conclusion

Structural assessments and corrective exercises can be integrated into any fitness program. Simply conduct your regular exercise programs and incorporate strategies that address any musculoskeletal imbalances you identify during the assessment process. Additionally, developing a thorough understanding of the individual structures of the body will help you to understand more complex information on movement and whole body mechanics.

The topic of the next installment of this series will be the lumbo-pelvic hip girdle. You will learn how to assess this area of the body, how it relates to other structures and some sample corrective exercises you can incorporate into your personal training programs.

References:

  1. Abelson, Dr. Brain and Abelson, Kamali. Release Your Pain. Calgary: Rowan Tree Books, 2003.
  2. Golding, Lawrence A. and Golding, Scott M. Fitness Professionals’ Guide to Musculoskeletal Anatomy and Human Movement. Monterey, CA: Healthy Learning, 2003.
  3. Gray, Henry. Gray’s Anatomy. New York: Barnes & Noble Books, 1995.
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  5. Price, Justin. “The Foot, Ankle and Knee”. IDEA Fitness Journal November-December 2006: 30-33.
  6. Price, Justin. “A Step-by Step Guide to the Fundamentals of Structural Assessment”. Lenny McGill Productions, 2006.
  7. Price, Justin. “A Step-by Step Guide to the Fundamentals of Corrective Exercise”. Lenny McGill Productions, 2006.
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