Adult Acquired Flatfoot (AAF)

Why do some adults get flat feet when they weren't born with flat feet ?

Occassionally I will get questions which are profound, as they give me insight into what people want to know as a whole. So whenever I get a good question I will try and answer it on this blog. This information may answer many of your questions that you did not know you had at the time, and may make for some intelligent reading as well.

The adult acquired flatfoot (AAF) is a progressive, symptomatic (painful) deformity resulting from gradual stretch of the tibialis posterior tendon as well as the ligaments that support the arch of the foot.

Most flat feet are not painful, particularly those flat feet seen in children. In the adult acquired flatfoot, pain occurs because soft tissues (tendons and ligaments) have been torn. The deformity progresses or worsens because once the vital ligaments and posterior tibial tendon are lost, nothing can take their place to hold up the arch of the foot.

The painful, progressive adult acquired flatfoot affects women four times as frequently as men. It occurs in middle to older age people with a mean age of 60 years. Most people who develop the condition already have flat feet. A change occurs in one foot where the arch begins to flatten more than before, with pain and swelling developing on the inside of the ankle. Why this event occurs in some people (female more than male) and only in one foot remains poorly understood. Contributing factors increasing the risk of adult acquired flatfoot are diabetes, hypertension, and obesity.

The following scheme of events is thought to cause the adult acquired flatfoot:

1) A person with flat feet has greater load placed on the posterior tibial tendon which is the main tendon unit supporting up the arch of the foot.

2) Throughout life, aging leads to decreased strength of muscles, tendons and ligaments. The blood supply diminishes to tendons with aging as arteries narrow.

3) Heavier, obese patients have more weight on the arch and have greater narrowing of arteries due to atherosclerosis. In some people, the posterior tibial tendon finally gives out or tears. This is not a sudden event in most cases. Rather, it is a slow, gradual stretching followed by inflammation and degeneration of the tendon.

4) Once the posterior tibial tendon stretches, the ligaments of the arch stretch and tear. The bones of the arch then move out of position with body weight pressing down from above. The foot rotates inward at the ankle in a movement called pronation. The arch appears collapsed, and the heel bone is tilted to the inside. The deformity can progress until the foot literally dislocates outward from under the ankle joint.

Treatment varies based on the stage of the disease, and each patient is treated differently based on findings. Arthritis, age, comorbidities, and whether it's flexible or rigid greatly influence the the foot and ankle surgeon's modalities. Surgery and bracing are key elements to reconstruction and palliative symptom control.

In this section, I encourage readers to submit questions/comments/personal stories/etc and I will definetly respond on this forum. I enjoy informing people about their conditions and the reasons why we do what we do for them. I do not have all the answers, as nobody can say they do, but I will strive to report the latest information available and keep you up to date as I go through these many topics.

Smoking and Bone Healing

After joining the Family Foot and Leg Center here in Naples, Florida, I have met quite a number of younger adult patients who have no idea of the deletarious effects that smoking can have on overall healing. Although this is a circumstantial finding backed by significant amounts of statistical evidence, many younger patients still are not aware of this. I thought it would be beneficial to enlighten everyone about this common topic.

Why are bones affected by smoking?


Bones are nourished by blood much like the other organs and tissues in your body. Nutrients, minerals, and oxygen are all supplied to the bones via the blood stream. Smoking elevates the levels of nicotine in your blood and this causes the blood vessels to constrict. Nicotine constricts blood vessels approximately 25% of their normal diameter. Because of the constriction of the vessels, decreased levels of nutrients are supplied to the bones. It is thought that this is the reason for the effect on bone healing, as the impending need for more oxygen and nutrients during fracture and osteotomy healing are not met, causing prolonged union time.

Evidence Based Medicine Review

"Cigarette smoking is detrimental to bony healing," said Dr. Franklin Chen, an orthopaedics instructor at Northwestern University Medical School in Chicago, Illinois, and lead author of a report presented at the recent annual meeting of the American Academy of Orthopaedic Surgeons (AAOS), held in New Orleans, Louisiana.
He and his colleagues focused on the 13-month healing rates of 54 patients who underwent surgery to help correct a specific type of (often work-related) wrist injury called symptomatic ulnar impaction syndrome. Chen says "95% of nonsmokers healed compared to 68% of smokers; this difference is statistically significant. The mean time to healing was 5 months for nonsmokers and 7.2 months for smokers." Previous studies have shown similar slower healing rates among smokers who have undergone spine or ankle fusion surgeries.

So that being said, it is important to note that when I or any of the physicians at our office "lecture" to you about the cessation of smoking and it's direct impact on your healing potential, we are not just being mean. It's based on clinical evidence that is monumental for your optimal outcome. This can impact healing time in stress fractures and wound healing as well, so cessation is your best bet!!!

Here is a link to a recent news article discussing this topic as well:

http://www.msnbc.msn.com/id/9730345/