The ability to exercise on a regular basis is important for health maintenance, weight reduction and cardiovascular health. The average person to takes between 8,000 and 10,000 steps a day, and with regular exercise can increase this number by two or three times. Healthy ankles are critical to most forms of aerobic exercise. There is no joint that is more susceptible to injury. Many researchers have established that ankles have been the most commonly treated joint based on numbers of emergency room visits.
The ankle joint carries the highest load of any joint in the body. The forces in the ankle joint are transferred through cartilaginous surfaces that are only one-third the surface area of the knee. The thickness of the cartilage is only one-third that of the knee. The cartilage within the ankle accepts more force per square inch than anywhere else in the body.
Despite this, degenerative joint disease is nine times less common in the ankle than in the knee. A large reason for this is the fact that the contour of the ankle joint provides for a higher percentage of cartilage contact throughout its entire range of motion than most other joints. Therefore, the forces are more evenly distributed to all of the cartilage cells within the ankle joint. By sharing the load more evenly, no one region is overused during normal motion. The close fit of the parts of the joint makes it more stable than most joint types.
The most common factors that do contribute to wear and tear on the ankle joint are trauma and abnormal mechanics. Trauma includes any twisting injuries or fractures while abnormal mechanics are typically caused by inherited traits, which could include high-arched feet, flat feet, or angulated ankles, knees or hips.
Trauma can largely be diminished by carefully choosing the locations that you exercise, and the type of shoe to exercise in. Running or walking on uneven terrain can greatly increase the likelihood of twisting your ankle. Running on only the right or left side of the road can cause repetitive micro trauma to the joints. It is best to alternate sides of the road, so your feet are not always tilted to one side or the other. Similarly, it is best to alternate directions when you run on a track.
Inherited traits can increase the forces on the ankle joint. For example, very flexible or flat feet can cause ankle strains, shin splints, instability and tendon injuries. Rigid or high-arched feet can cause impact-related injuries. These conditions can commonly be controlled with careful shoe selection or in some cases with the use of custom-made orthotics. Motion control shoes are best for flexible feet, while cushioned shoes are typically best for high-arched feet.
A large percent of ankle pain is due to inflammation of the inner lining of the ankle joint (synovitis). This may result from repetitive micro trauma or acute injuries. In many cases this can be well treated with anti-inflammatories, rest, ice, elevation, cortisone or other conservative measures.
Injuries to ligaments or bone fractures happen frequently with twisting or high energy direct trauma. Ligaments which are partially torn or disrupted most frequently will heal without surgery. Complete rupture of ligaments will often require surgical repair. The type, shape and size of fractures will determine whether conservative care or surgical intervention is most appropriate.
Damage to cartilage varies greatly from chronic wear and tear associated with degenerative joint disease (arthritis) to acute injuries (fractures or loose fragments within the joint). Conservative care has been noted to manage many arthritic conditions. The early stages of arthritis respond well to over-the- counter braces while custom- made braces or shoe inserts may be used for resistant cases.
Surgical options for cartilage damage include the following:
Arthroscopy - This is intended to remove damaged or loose cartilage fragments. This can also be used to perform debridement down to the underlying bone to stimulate the growth of fibro-cartilage to replace the missing original cartilage. This is commonly referred to as micro-fracture surgery.
Osteo-articular transfer graft - This is the removal of a portion of damaged cartilage as well as the underlying bone and replacing it with a graft of bone and overlying cartilage that is intact. This can be performed with the graft removed from a donor or from the patient.
Distraction arthroplasty - With the use of an external fixator, a joint can be distracted to allow the tissue to heal without direct pressure on the damaged cartilage cells.
Arthrodesis (fusion) - This is still considered the"gold standard" for severely damaged joints. With this procedure, a painful and poorly functioning joint is fused to form a joint without motion, but also lacking pain.
Any ankle pain which limits regular daily activities is not considered"normal." Pain which is recurrent or persistent should be evaluated by a foot and ankle specialist.
Dr. Mark Hartman is affiliated with Trimark Foot and Ankle. He is certified by the American Board of Podiatric Surgery in foot surgery and in reconstructive rearfoot/ankle surgery.