Nov 06 2009
Hypothyroidism and Plantar Fasciitis
It is well documented that musculoskeletal conditions, such as carpal tunnel syndrome, Dupuytren’s contracture and trigger finger, occur in association with thyroid disease. Most disorders occur with hypothyroidism, but there have been occurrences with thyrotoxicosis as well. Although there is limited research to support a clear association between hypothyroidism and plantar fasciitis, it is theorized that low thyroid levels will increase the susceptibility for the development of plantar fasciitis.
Plantar fasciitis is the tearing, inflammation and deterioration of the plantar fascia, a connective tissue band which supports the arch. Plantar fasciitis classically causes heel pain at the first step in the morning or upon rising after long periods of rest. The plantar fascia is similar in structure to a ligament and is composed of mostly collagen, but also elastin and GAGs, which are long carbohydrate chains known to attract water and increase resiliency. Musculoskeletal disorders result from hypothyroidism because low thyroid levels cause deposits within the connective tissue. This occurs because thyroid hormone inhibits fibroblasts. Fibroblasts are cells within connective tissue which produce and secrete substances important in connective tissue structure, such as collagen, elastin, GAGs and fibronectin. With normal levels of thyroid hormone, these substances are not overproduced. When thyroid levels are low, fibroblasts overproduce these substances, particularly GAGs. GAGs attract water and increased deposits in the fascia disrupt the collagen network by increasing the space between collagen fibers. The strength of the plantar fascia is due in part to the organized array of collagen fibers. The additional GAGs, additional water content and increased spacing decreases the overall strength of the fascial band, which increases it’s susceptibility to tearing. Microscopic tears may occur in the plantar fascia under normal conditions, and this results in plantar fasciitis.
More information on plantar fasciitis.
More information on plantar fasciosis.
Clin Endocrinol (Oxf). 2003 Aug;59(2):162-7.
Pain under the heel at the first step in the morning is the most characteristic symptom associated with plantar fasciitis. Plantar fasciitis is the tearing, inflammation and degeneration of the plantar fascia, an important connective tissue structure in the bottom of the foot. The plantar fascia is similar in structure to a ligament and is composed of collagen, elastin, glycosaminoglycans (GAGs), fibroblasts and water. 
Type I collagen adds to the fascia’s considerable strength and the elastin increases elasticity, as the name implies. Glycosaminoglycans are long chains of repeating sugar units which attract water and function to resist pressure. 
The plantar fascia is a thick, fibrous, connective tissue band which extends along the bottom of the foot. The structural make up of the plantar fascia consists of collagen, elastin, glycosaminoglycans and water. The primary cells are fibroblasts, which synthesize collagen. The primary component of the fascia is type I collagen which adds to the strength of the structure. Elastin is a protein which gives the fascia some elasticity as well as increasing it’s function in dynamic arch support when walking. Glycosaminoglycans, GAGs, are long chains of repeating sugar units that attract water and add resiliency to the ligamentous structure. 
Plantar fasciitis is a condition which results from microscopic tears within the plantar fascia. The plantar fascia, a ligament-type structure in the foot, is one of the most important structures in the foot due to it’s role in supporting the arch. Despite it’s strength, excess stress in combination with abnormal mechanics of the foot can result in small tears within the fascia. In the illustration to the left, a tear in the plantar fascia is highlighted. An up-close view shows a microscopic image of the tearing in the ligamentous structure. 
Plantar fasciosis is the degeneration (deterioration) of the plantar fascia as a result of repetitive stress. The plantar fascia is a broad, thick, fibrous band that extends from the base of the calcaneus (heel bone) to the base of the toes. The fascia is composed of a dense network of highly organized collagen fibers, which gives it the strength necessary to support the tremendous force placed through the arch when walking. During the push off or propulsive phase of walking, the plantar fascia tightens like a cable, increasing the arch height, shortening the foot and helping to create a rigid lever which increases the efficiency of motion as the body is propelled forward. 
When Eli Manning was diagnosed with plantar fasciitis, the condition suddenly became a common, household term. Manning had an unusual, acute development of plantar fasciitis due to a combination of his foot placement during his throw and history of arch pain. Manning is not the only player with plantar fasciitis. Tank Johnson, defensive tackle for the Cincinatti Bengals is questionable for Sunday’s game against the Bengals due to plantar fasciitis. 
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Willie Parker is still suffering from turf toe, a hyperextension injury of the great toe joint, and is unsure if he’ll play against the Browns this Sunday. Turf toe is a tear of the capsule and ligaments at the base of the great toe joint. In football, a common mechanism of injury is when a player’s ankle is flexed, his weight is on the ball of his foot and he falls back on his own leg, or another player falls on the leg. The weight of the player on the leg jams the foot down and forces the great toe into a hyperextended position, causing a rupture of the joint tissues. Turf toe can sideline an athlete for weeks, depending on the grade of the injury. 
Last week it was questionable whether Eli Manning, the quarterback for the New York Giants, would start in yesterday’s game against the Raiders. Not only did he start his 83rd straight game for the Giants, he led the Giants to an easy 44-7 victory over the Raiders. Manning took at seat on the sidelines midway through the second quarter after completing 8 of 10 passes for 173 yards and connecting for 2 touchdowns. 
Tom DeLay had to drop out of the Dancing with the Stars competition due to stress fractures in both of his feet. Tom DeLay was the DeLay, Republican majority leader in the U.S. House of Representatives, known for his tough conservative approaches, initially injured his right foot and then on Monday sustained a stress fracture to his left. Stress fractures, incomplete breaks in the bone, are repetitive stress injuries and typically occur in the long bones in the feet. The 2nd and 3rd metatarsal bones are the two most common bones to fracture. The metatarsal bones are the long bones in the middle of the foot. The pain is usually sharp and develops suddenly, but it is typically not due to a specific injury or trauma. More on 
Eli Manning, the quarterback for the New York Giants, has been diagnosed with an injury to his plantar fascia. Manning limped off the field early in the 4th quarter of last Sunday’s game with a painful right heel. An MRI has confirmed inflammation of his plantar fascia, a strong, web-shaped ligament-type structure in the bottom of the foot. 
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Eli Manning, quarterback for the New York Giants, dropped to the ground after completing a pass early in the 4th quarter of yesterday’s game against the Kansas City Chiefs. He stayed in for one more play and then left the game. Although an MRI is not scheduled, it may come at a later date, depending on the diagnosis and update by the team physician. (
Shoe gear has always been assumed to be associated with foot pain, but very few studies have explored the relationship. A new study in the journal Arthritis and Rheumatism collected data from the Framingham Study to examine the association between shoe gear and foot pain. Between 2002-2008, 3,378 individuals were evaluated for foot pain and asked “on most days, do you have pain, aching or stiffness in either foot?” The area of foot pain (hindfoot, arch, forefoot or toes) was also recorded. The participants were asked to identify the type of shoes they wear on most days. They were also instructed to identify the type of shoe they wore most often over the past five years. Shoe quality was based on structure and support of the shoe and divided into three categories, adjusting for age, gender, height, weight and smoking: 
