Posterior tibial tendon dysfunction or PTTD is a dysfunction of the posterior tibialis muscle, resulting in a fallen arch, or flat feet. As the muscle inverts the foot, when it is not working fully, the arch of the foot collapses. This can then cause other conditions and injuries such as plantar fasciitis which makes the foot painful.
Symptoms of posterior tibial tendon dysfunction
One of the main signs of PTTD is a fallen or flattened arch of the foot. The patient may also have a history of injury to the tibialis posterior muscle. Pain in the foot may be a symptom although this is usually associated with a secondary condition, such as a tendinopathy or a muscle or tendon tear in the foot.
What is posterior tibial tendon dysfunction?
There is much confusion over the name of this condition with it being referred to as any of the following:
- Posterior tibial tendon dysfunction (PTTD)
- Posterior tibial tendon syndrome
- Tibialis posterior syndrome
- Posterior tibial insufficiency
- Adult acquired flatfoot
All of these conditions are the same and so we will interchange them in this article.
The tibialis posterior muscle originates from behind the shin bone or tibia and runs into a tendon that passes behind the bony bit on the inside of the ankle called the medial malleolus. The function of tibialis posterior is to plantar flex the ankle or point the foot down and also to invert the foot orturn the sole of the foot inwards.
There is sometimes confusion between this condition and that of tibialis posterior tendinopathy and the terms are often used interchangeably. The true meanings of these conditions are slightly different however. Tibialis posterior tendinopathy is a degenerative, painful injury to the tendon of the tibialis posterior. Posterior tibial syndrome is slightly different and is a dysfunction of the muscle, resulting in a fallen arch, or flat feet.
Because the Tibialis Posterior muscle is responsible for inverting the foot, if it is not working correctly, then this causes the arch of the foot to flatten when we stand, walk or run. The fallen arch or flat feet can then cause further injury problems such as plantar fasciitis.
Treatment of any associated conditions such as tibialis posterior tendinopathy is important. If the injury is painful or acute then rest and application of ice or cold therapy can reduce pain, inflammation and swelling.
Arch support insoles or orthotic insoles may help correct biomechanical problems of the foot. Long term it is important to strengthen the tibialis posterior muscle. This is done in a similar way as strengthening the calf muscles with plantar flexion type exercises but with inversion of the ankle as well. Begin with strengthening exercises using a resistance band and as pain allows and strength improves move onto calf raise type exercises.
Exercises for PTTD
The Tibialis Posterior muscle works to both invert and plantarflex the foot ankle. These movements can be recreated using an elastic rehab band for resistance. The resistance band is looped around the mid foot and pulled out to the side as shown. The foot is then moved into inversion by turning the sole inwards and plantarflexion or pointing the toes down at the same time.
Initially aim for 3 sets of 10 repetitions increasing to 3 sets of 20 twice a day. If the exercise then becomes too easy the strength of the resistance band can be increased.