Experiencing pain on the inside of your ankle that’s exacerbated by physical activity? Struggle to stand up on the tiptoes of the affected foot because it feels too weak and painful? Swear that your arches are getting flatter?
These are all telltale signs of a common condition we see in podiatry called posterior tibial tendon dysfunction (PTTD), which when left unmanaged in the ‘hopes’ that it will go away on its own, can lead to fallen or collapsed arches, with PTTD being the most common cause of adult acquired flatfoot - one of the very few ways flat arches can ‘develop’ in adulthood. Here’s what you should know.
What Is Posterior Tibial Tendon Dysfunction?
PTTD describes injury or damage to a tendon called the posterior tibial tendon, which runs down the side of the lower leg, crossing the inside of the ankle and attaching to several areas on the underside of the foot. The posterior tibial tendon plays a very important role in the structure of our feet and the stability of our arches, as well as helping support healthy and pain-free movement every time we take a step.
Posterior Tibial Tendon Dysfunction Causes
PTTD is what we call an overuse condition, meaning that it is caused by repetitively overloading and straining the tendon past its limits, which results in damage, inflammation and ultimately the temporary inability of the tendon to carry out its role until it has healed and strength and function has been restored with the help of a management and rehab plan. Contributing factors to the development of PTTD can include:
- Having a naturally flatter foot type, which can put more stress on the tendon
- Biomechanical or alignment issues in the feet
- Wearing flat, unsupportive footwear which overloads the posterior tibial tendon, especially when it is used to being supported
- Walking or working on hard surfaces, which may increase the stress on the feet
- Regular physical activity such as running, long-distance walking, hiking and climbing stairs
- Increased weight, which increases the demand on the tendon
- Conditions such as diabetes and hypertension
- Previous injury to the ankle or the posterior tibial tendon
Symptoms Of PTTD
PTTD often affects one foot (typically the ‘leading’ foot), though it can develop in both feet. Without effective management, the symptoms of PTTD tend to progressively worsen to result in a partial tear or even a complete rupture of the tendon. Given the importance of the tendon in maintaining the stability of the arch of the foot, this means it can lead to arch collapse and a case of adult acquired flat foot.
If you’re starting to recognise some of these symptoms, you should know that PTTD can be characterised into four stages of progression:
Stage one of PTTD is often missed because it comes with little or no symptoms. Even if you’re sent for medical imaging (like ultrasound), it typically won’t come back with significantly abnormal findings. With this said, you may have some mild inflammation of the tissue surrounding the tendon that you or your podiatrist may identify, which can be your first sign.
At stage one, you can also still perform a single heel raise test. To perform the test, hold onto the wall or a chair, beginning in a standing position and lift the unaffected foot up off the ground. Now, attempt to lift onto the toes of the affected foot. At stage one, you should still be able to do this without any issues.
At stage two of PTTD, there is damage to the posterior tibial tendon at a level that will affect its regular function. You may notice that your foot has become flatter. Medical imaging may reveal an arch collapse deformity. During a physical examination, you’ll no longer be able to complete the single-leg heel raise test.
Now we’re getting into the more severe stages, with stage three being characterised by significant degeneration and rigid deformities at the ankle with notable movement restrictions. A physical examination at this stage will reveal severe sinus tarsi pain (with the sinus tarsi being a small passageway at the ankle joint towards the outside of the ankle) while imaging will typically show ankle arthritis with an arch collapse deformity.
By stage four, the deltoid ligament (located on the inside of the ankle that supports ankle joint stability) is compromised and there are degenerative changes at the ankle joint. The flatfoot deformity is worse and rigid throughout the foot. A physical examination typically shows ankle pain and severe sinus tarsi pain. As for imaging, it will show an arch collapse deformity, subtalar arthritis, and a tilt at the talus bone that forms part of the ankle.
So how can you spot PTTD in its early stages before significant changes have started occurring? Look for:
- Pain and tenderness on the inside of the ankle
- Redness and warmth
- Flattening of the arch
- Pain exacerbated by activity
- Pain on palpation of the inside of the ankle behind the bony bump (medial malleolus)
How is PTTD treated?
When it comes to PTTD, the earlier you can start managing it, the better. This is as getting in early can go a long way in helping stop the progression of painful symptoms and further damage to the posterior tibial tendon. The PRICE principles (protection, rest, ice, compression and elevation) can be used initially to help reduce painful symptoms before you’re able to see your podiatrist. Treatment then needs to focus on addressing the cause of the PTTD, based on its current severity and the symptoms you’re experiencing. This may include:
- Custom foot orthotics to support the posterior tibial tendon, support the arch, and correct any other biomechanical or alignment issues
- Supportive footwear that stabilises the foot at the ankle and limits the foot rolling in and hence placing more strain on the posterior tibial tendon
- Stretching and strengthening to address tight or weak supporting muscles
- Strapping the ankle to reduce strain on the tendon
- Activity modification to reduce the strain on the posterior tibial tendon while it heals
- Where injury to the tendon is severe, such as a significant tear, a brace or cast may be required to completely off-load the tendon
- If the PTTD is severe, a referral to explore surgical options may be necessary.
Have any questions about posterior tibial tendon dysfunction or adult acquired flat foot, or need to book an appointment? Give us a call on +852 2801 4801 or email us on email@example.com