When the plantar fascia is stressed, the risk of tiny tears and inflammation increases. Stress on the fascia along the bottom of your foot may occur for a number of reasons including overuse, improper footwear, a fascia that is too tight, weakened tissue, or having other conditions that puts the plantar fascia at risk.
Overuse and Overloading
The main cause of plantar fasciitis is overuse and overloading the plantar fascia in occupations where you are on your feet all day (teachers, store clerks, soldiers, waitresses, hostesses), activities that require you to push heavy items (shippers and receivers, construction workers) and/or sporting activities in which you overexert yourself (doing too much, too fast and/or too soon), especially running, football, baseball, basketball, tennis, volleyball, step-aerobics, stair climbing and dancing. Running on your toes or the balls of your feet, on very hard or soft surfaces, and up hills can increase your risk and suffering.
Among professional athletes, plantar fasciitis is one of the 5 most common foot and ankle injuries. However, weekend warriors or people who have a rapid change in their activity levels are prone to this condition.
Your plantar fascia is only able to stretch to 102% of its length without tearing; therefore it may not be strong enough to withstand the stress placed on it by your lifestyle.
Approximately 90% of women and 40% of men with plantar fasciitis are overweight. Obesity or sudden weight increases can overstretch and increase the tension placed on your plantar fascia. The additional weight gained during pregnancy along with the hormonal changes can cause your ligaments and tissues to relax, which heightens your risk for this disorder.
Another common causes of Plantar Fasciitis is the shortening of the plantar fascia. If your foot is held for long periods of time in a position where your toes are pointed, the plantar fascia may become shortened. Within the body muscles, tendons, or ligaments that are in a shortened position for any length of time will become tighter and shorter. Image the neck of a T-shirt that becomes permanently deformed if it is stretched too much.
Faulty foot structures(abnormal growths, different leg lengths, arch variations, and unhealed injuries), muscle imbalances (tight, weak or shortened muscles in your foot, ankle, calf and hamstring) andpoor biomechanics (abnormal twisting of your foot) affect the way your foot hits the ground (your gait).
Overpronation (feet rolling inward) is found in 85% of people who suffer from plantar fasciitis. These individuals tend to have a low arch and flat foot (pes planus). Those who underpronate (feet rolling outward) tend to have rigid feet and a high arch (pes cavus) which results in a shortened plantar fascia. These issues place increased pressure on your plantar fascia when your foot hits the ground.
As you age your tissues break down and weaken; your plantar fascia changes from an elastic-like fiber to a more rigid, rope-like fiber, the fat pad in your heel thins out and doesn’t provide as much cushioning, which cause it to swell, bruise and/or tear.
Worn out, old, poorly constructed shoes that don’t fit properly or don’t support your heel or arch affect the distribution of your body weight on your foot and add undue stress to your plantar fascia. High heeled shoescommonly worn by women are famous for leading to the eventual shortening of the plantar fascia. They don’t just shorten the plantar fascia, they shorten the calf muscles as well. Whenever you stand on your toes these muscles contract and shorten. Tight calf muscles can increase the problems associated with Plantar Fasciitis.
Other factors that may cause plantar fasciitis are:
- Neurological disorders that affect the brain or nervous system (nerve damage from tarsal tunnel syndrome, tibial/plantar/calcaneal nerve entrapment or irritation)
- Diabetes, Osteoarthritis and Inflammatory disorders – rheumatoid arthritis, Reiter’s disease, Behcet syndrome, ankylosing spondylitis, spondyloarthropathies, diffuse idiopathic skeletal hyperostosis, bowel disease, psoriasis, fibromyalgia
- Disk herniation
- Stress fractures of calcaneus or bone tumors