Posterior Tibial Tendon Dysfunction, also known as PTTD and Posterior Tibial Tendinitis, is the term used to describe what happens when a patient's Posterior Tibial Tendon fails. Arch development in humans is gradual, most babies learn to roll and crawl before taking their first steps. As the foot becomes accustomed to supporting weight arches in the foot become more pronounced, fat padding decreases, bones harden, lengthen, and by the time children are able to run their Posterior Tibial Tendons are typically comfortable in their role.
PTTD is a leading cause of adult flatfoot, having flat feet is not necessarily a pathological condition, however once the Posterior Tibial Tendon starts deteriorating loss of normal foot function should be anticipated. There are several symptoms of PTTD: patients may complain of medial ankle pain, midfoot pain, complaints of pain on lateral side of the foot typically accompany advanced PTTD as the far side of the foot is forced to accept an increased load, navicular swelling may be present, when viewed from behind the patient may present what is known as 'Too Many Toes'. This non-scientific designation represents movement of the foot away from the midline.
Initially PTTD may be nothing more than a mild annoyance or discomfort. While women are usually affected more than men, athletes that play sports where lateral foot movement is heavy may also be at risk for developing PTTD. Court shoes such as those worn by basketball players, indoor volleyball players, and those who play tennis or indoor soccer will have a flatter, broader sole/midsole combination than running shoes. Court shoe design takes into account the frequent side to side motions made by those who play court sports.
The Posterior Tibial Tendon has an insertion point on the navicular bone. It also branches off to attach to each of the three cuneiforms, metatarsal bones I-V, and the cuboid bone. The PT tendon plays a critical role during the gait cycle, especially during weight bearing segments where the upper body mass passes over the subtalar joint. This tendon allows your foot to plantarflex, and is considered a rear foot inverter. Loss of PT tendon functionality means the Peroneal Brevis Tendon is unopposed. This muscular imbalance deforms the foot, over time the arch flattens and the ankle rolls inward creating the condition known as PTTD.
Tendon surgery is at best a dicey operation since this tendon exists in a hypovascular state. Any tendon injury, whether from trauma or neglect, will heal extremely slowly, if at all. A ruptured Posterior Tibial Tendon will be practically impossible to repair, surgical success depends on getting to the tendon before the tear is complete. A condition known as equinus may also stress the the Posterior Tibial Tendon. Equinus is an inability to dorsiflex the foot to the degree necessary for normal gait. A foot that can not dorsiflex (move the toes towards the shin) properly will spend a greater amount of time being plantar flexed (toes pointed downwards, ballerina style), this disrupts normal range of motion and forces the body to compensate for its deficiencies.
Equinus may be a structural deformity, however it may also be the result of overly tight muscles. Most shoes elevate the heel, forcing the heel into an unstable elevated position shortens muscles and restricts tendon movement. Walking around in heels can send tendons into hibernation, the higher the heel, the less stretch the tendon receives, the greater the likelihood a tendon will not want to return to its previous length. Several sources mention that PTTD is a progressive condition. Once acquired it is difficult to get rid of it, left untreated, the condition will worsen so identification of an at risk tendon is crucial for good foot health.
PTTD may be the result of trauma or an overuse injury. Obesity, diabetes, arthritis, peripheral neuropathy, and other factors may contribute to PTTD development. One way to test how well your Posterior Tibial Tendon is working is to try a single foot heel raise. If your Posterior Tibial Tendon is functioning optimally raising your body weight on either foot should be easily accomplished, without pain. Before diagnosing yourself, or anyone else, with PTTD keep in mind that the Posterior Tibial Tendon is a single tendon that works in conjunction with many other structures. An inability to raise yourself on a single heel may indicate PTTD or it may be another, unrelated condition.
Treatment of PTTD depends on the patient and the severity of the condition. If the foot is flexible; foot orthoses, braces, and physical therapy are considered appropriate conservative options. Medications such as over the counter anti-inflammatories may be taken or higher doses prescribed, injections carry the risk of tendon rupture so are generally not recommended. Several surgical approaches may be undertaken: the tendon may be cleaned, rebuilding the medial arch may be attempted, joint fusions work yet leave the patient with a rigid foot that is unable to move from side to side. None of these will return full elasticity to the tendon, all carry the risk of a post-operative infection, pain, expense, time off of the afflicted foot, and the possibility of failure.
To summarize: Posterior Tibial Tendon Dysfunction is a common ailment that contributes to flatfoot formation in adults. An inability to complete a successful single heel raise, Too Many Toes, midfoot pain, navicular swelling, and limited inversion are indicators that the Posterior Tibial Tendon may be deteriorating. Rest, ice, foot orthoses, braces, stretching, physical therapy, and anti-inflammatories are common treatments for the condition. Once acquired, careful monitoring is necessary to prevent further degeneration. Tendon integrity may be preserved by keeping the muscle and tendon supple. Avoidance of high heels, improperly fitted footwear, footwear that lacks adequate support, and overuse will help maintain good foot and tendon health.
Sources:
- http://www.foothealthfacts.org/footankleinfo/pttd.htm
- http://www.oandp.org/jpo/library/1999_01_002.asp
- http://ilstraining.com/ds%20solutions/LEDSS/PTTD.html
- http://www.drtepper.com/pttd.html