What is PTTD?
Posterior tibial tendon dysfunction (PTTD) is an inflammation, overstretching or degenerative condition (tendinosis) of the posterior tibial tendon. This tendon originates on the back of the tibia (large bone) in the leg, runs along the inside of the ankle and inserts at many points in the arch of the foot. The posterior tibial muscle (and tendon) plays a large role in supporting the arch of the foot and in walking and running. When this muscle and/or tendon are damaged, there can be pain along the inside of the ankle and progressive flattening of the foot can occur.
What Happens When the Posterior Tibial Tendon Is Damaged?
The posterior tibial muscle and tendon functions to support the arch of the foot and to aid in walking and running. When this tendon is damaged, the arch of the foot can flatten. This can happen in one instance (as a result of injury) or progressively over the course of months to years. This typically happens in one foot but can occur in both feet. Changes in the foot structure are gradual (or progressive) meaning that this will get worse over time, particularly if it is not treated early.
PTTD is often called “adult-acquired flatfoot” because it is the most common type of flatfoot developed during adulthood.
Causes of PTTD
An acute injury, such as from a fall, can tear the posterior tibial tendon or cause it to become inflamed. The tendon can also tear due to overuse. For example, people who do high-impact sports, such as basketball, tennis, or soccer, may have tears of the tendon from repetitive use. Once the tendon becomes inflamed or torn, the arch will slowly fall (collapse) over time.
Posterior tibial tendon dysfunction is more common in women and in people older than 40 years of age. Additional risk factors include obesity, diabetes, and hypertension.
Symptoms of PTTD
The symptoms of PTTD may include pain, swelling, a flattening of the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change.
- When PTTD initially develops, typically there is pain on the inside of the foot and ankle (along the course of the tendon). In addition, the area may be red, warm, and swollen.
- Later, as the arch begins to flatten, there may still be pain on the inside of the foot and ankle. But at this point, the foot and toes begin to turn outward and the ankle rolls inward.
- As PTTD becomes more advanced, the arch flattens even more and the pain often shifts to the outside of the foot, below the ankle. The tendon has deteriorated considerably and arthritis often develops in the foot. In more severe cases, arthritis may also develop in the ankle.
The proper diagnosis of PTTD as well as any underlying foot deformity starts with a physical exam. Your Weil Foot & Ankle Surgeon will take a thorough history of your foot problem. Then, he or she will examine your foot looking for:
- Swelling: This swelling is from the lower leg to the inside of the foot and ankle and along the course of the posterior tibial tendon.
- Changes in the shape of the foot: The heel may be tilted outward and the arch will have collapsed.
- “Too many toes” sign. When looking at the heel from the back of the patient, usually only the fifth toe and half of the fourth toe are seen. In a flatfoot deformity, more of the little toe can be seen.
- “Single limb heel rise” test: Being able to stand on one leg and come up on “tiptoes” requires a healthy posterior tibial tendon. When a patient cannot stand on one leg and raise the heel, it suggests a problem with the posterior tibial tendon.
- Limited flexibility: The doctor may try to move the foot from side to side. The treatment plan for posterior tibial tendon tears varies depending on the flexibility of the foot. If there is no motion or if it is limited, there will need to be a different treatment than with a flexible foot.
- The range of motion of the ankle is affected. Upward motion of the ankle (dorsiflexion) can be limited in flatfoot. The limited motion is tied to tightness of the calf muscles.
X-rays will be taken to evaluate the structure of the foot and to see if any arthritis or arthritic-like changes have occurred in the back portion of the foot. If surgery is needed, they help the doctor make measurements to determine what surgery would most helpful.
These studies can create images of soft tissues like the tendons and muscles. An MRI may be ordered if the diagnosis is in doubt. The Weil Foot & Ankle Institute has three extremity MRI’s on site at our Des Plaines, Highland Park, and Lincoln Park locations. These extremity MRI’s only take about 30 minutes for the study and only requires the patient put their foot into a painless machine avoiding the uncomfortable claustrophobia that some MRI devices create.
Computerized Tomography Scan (CT Scan)
These scans are more detailed than x-rays. They create cross-section images of the foot and ankle. Because arthritis of the back of the foot has similar symptoms to posterior tibial tendon dysfunction, a CT scan may be ordered to look for arthritis.
An ultrasound uses high-frequency sound waves that echo off the body. This creates a picture of the bone and tissue. Sometimes more information is needed to make a diagnosis. An ultrasound can be ordered to show the posterior tibial tendon.
Because of the progressive nature of PTTD, it’s best to see your Weil Foot and Ankle Surgeon as soon as possible. If treated early enough, your symptoms may resolve without the need for surgery and progression of your condition can be arrested. In contrast, untreated PTTD could leave you with an extremely flat foot, painful arthritis in the foot and ankle, and increasing limitations on walking, running, or other activities. Some of the initial treatments for PTTD include:
- Rest: Decreasing or even stopping activities that worsen the pain is the first step. Switching to low-impact exercise is helpful. Biking, elliptical machines and swimming do not put a large impact load on the foot, and are generally tolerated by most patients.
- Ice: Apply cold packs on the most painful area of the posterior tibial tendon for 20 minutes at a time, 3 or 4 times a day to keep down swelling. Do not apply ice directly to the skin. Placing ice over the tendon immediately after completing an exercise helps to decrease the inflammation around the tendon.
- Nonsteroidal Anti-inflammatory Medication: Drugs, such as ibuprofen, naproxen, Celebrex and mobic, reduce pain and inflammation. Taking such medications about a half of an hour before an exercise activity helps to limit inflammation around the tendon. Talk with your primary care doctor if the medication is used for more than 1 month.
- Immobilization: A short leg cast or walking boot may be used for 6 to 8 weeks. This allows the tendon to rest and the swelling to go down. However, a cast causes the other muscles of the leg to atrophy (decrease in strength) and thus is only used if no other conservative treatment works.
- Orthotics: Most people can be helped with orthotics and braces. An orthotic is a shoe insert. It is the most common nonsurgical treatment for a flatfoot. An over-the-counter orthotic may be enough for patients with a mild change in the shape of the foot. A custom orthotic is required in patients who have moderate to severe changes in the shape of the foot. The custom orthotic is more costly, but it allows the doctor to better control the position the foot.
- Braces: A lace-up ankle brace may help mild to moderate flatfoot. The brace would support the joints of the back of the foot and take tension off of the tendon. A custom-molded leather brace is needed in severe flatfoot that is stiff or arthritic. The brace can help some patients avoid surgery.
- Physical Therapy: Physical therapy that strengthens the tendon can help patients with mild to moderate disease of the posterior tibial tendon.
- Steroid Injection: Cortisone is a very powerful anti-inflammatory medicine that your doctor may consider injecting around the tendon. A cortisone injection into the posterior tibial tendon is not normally done. It carries a risk of tendon rupture. Discuss this risk with your doctor before getting an injection.
When Is Surgery Needed?
In cases of PTTD that have progressed substantially or have failed to improve with non-surgical treatment, surgery may be required. For some advanced cases, surgery may be the only option. Surgical treatment may include repairing the tendon, realigning the bones of the foot or both. Reconstruction of the flatfoot is extremely complex. The following is a list of the more commonly used operations. Additional procedures may also be required.
- Gastrocnemius Recession or Lengthening of the Achilles Tendon: This is a surgical lengthening of the calf muscles. It is useful in patients who have limited ability to move the ankle up (equinus). This surgery can help prevent flatfoot from returning but it does create some weakness with pushing off and climbing stairs. Complication rates are low but can include nerve damage and weakness. This surgery is typically performed together with other techniques for treating flatfoot.
- Tenosynovectomy (Cleaning the Tendon): This surgery is used when there is very mild disease, the shape of the foot has not changed, and there is pain and swelling over the tendon. The surgeon will clean away and remove the inflamed tissue (synovium) surrounding the tendon. This can be performed alone or in addition to other procedures. The main risk of this surgery is that the tendon may continue to degenerate and the pain may return.
- Tendon Transfer: Tendon transfer can be done in flexible flatfoot to recreate the function of the damaged posterior tibial tendon. In this procedure, the diseased posterior tibial tendon is removed and replaced with another tendon from the foot, or, if the disease is not too significant in the posterior tibial tendon, the transferred tendon is attached to the preserved (not removed) posterior tibial tendon.
- One of two possible tendons is commonly used to replace the posterior tibial tendon. One tendon helps the big toe point down and the other one helps the little toes move down. After the transfer, the toes will still be able to move and most patients will not notice a change in how they walk.
- Although the transferred tendon can substitute for the posterior tibial tendon, the foot still is not normal. Some people may not be able to run or return to competitive sports after surgery. Patients who need tendon transfer surgery are typically not able to participate in many sports activities before surgery because of pain and tendon disease.
- Osteotomy (Cutting and Shifting Bones): An osteotomy can change the shape of a flexible flatfoot to recreate a more “normal” arch shape. One or two bone cuts may be required, typically of the heel bone (calcaneus).
The Surgeons of the Weil Foot & Ankle Institute have pioneered a procedure called the Calcaneal Scarf. In this procedure, the heel bone is cut and moved in such a way that the flatfoot is corrected. The bone cut is held in place with a screw and bone graft may be used to help with the stability of the bone. This can be performed in conjunction with other procedures.
- Fusion: Sometimes flatfoot is stiff or there is also arthritis in the back of the foot. In these cases, the foot will not be flexible enough to be treated successfully with bone cuts and tendon transfers. Fusion (arthrodesis) of a joint or joints in the back of the foot is used to realign the foot and make it more “normal” shaped and remove any arthritis. Fusion involves removing any remaining cartilage in the joint. Over time, this lets the body “glue” the joints together so that they become one large bone without a joint, which eliminates joint pain. Screws or plates hold the bones in places while they heal. Side-to-side motion is lost after this operation. Patients who typically need this surgery do not have a lot of motion and will see an improvement in the way they walk. The pain they may experience on the outside of the ankle joint will be gone due to permanent realignment of the foot. The up and down motion of the ankle is not greatly affected. With any fusion, the body may fail to “glue” the bones together. This may require another operation.
The most common complication is that pain is not completely relieved. Nonunion (failure of the body to “glue” the bones together) can be a complication with both osteotomies and fusions. Wound infection is a possible complication as well.
Most patients have good results from surgery. The main factors that determine surgical outcome are the amount of motion possible before surgery and the severity of the flatfoot. The more severe the problem, the longer the recovery time and the less likely a patient will be able to return to sports. In many patients, it may be 12 months before there is any great improvement in pain.
Publications by Weil Foot & Ankle Institute physicians on this topic: