Posterior Tibial Tendon Dysfunction
The posterior tibial tendon passes around the ankle to attach the tibialis posterior muscle (one of the deep calf muscles) to the bones of the mid foot. It provides stability to the arch and supports the foot while walking. Inflammation or a tear of this tendon may cause dysfunction, leading to pain, collapse of the medial arch and the development of a flatfoot.
Symptoms of flatfoot include pain on the inside of the ankle and foot that may be accompanied by swelling. Flatfoot may cause the heel to shift outwards, causing pain on the outside of the ankle as well. Activities such as walking, running, and standing on your toes may aggravate pain. If treatment is delayed the deformity may become rigid and arthritis can develop. You may have trouble walking or wearing shoes.
When you present with these symptoms, a thorough medical history and physical examination is required to make the diagnosis and determine what stage the flatfoot is. Examination includes testing for pain, swelling, changes in ankle position, flexibility, strength and range of motion. A weightbearing set of foot and ankle x-rays is the most important imaging test, but advanced imaging with MRI, CT and ultrasound may also be required.
Posterior tibial tendon dysfunction in its early stages may be treated with rest, cold packs, immobilisation, physiotherapy, steroid injection and anti-inflammatory medications. Shoe inserts that support the arch may be recommended. Surgery may be necessary if conservative treatments fail and may include:
- Tenosynovectomy: The inflamed tendon tissue is cleaned and removed.
- Lengthening of the Achilles tendon.
- Tendon transfer: The damaged tibialis posterior tendon is replaced by another foot tendon, usually the flexor digitorum longus (FDL) tendon.
- Osteotomy: Bones of the heel and midfoot may be cut and re-aligned to reconstruct the arch of the foot.
- Lateral column lengthening: In this procedure, a small wedge-shaped piece of bone is taken from the hip and placed into the outside of the calcaneus. This helps realign the bones and recreates the arch.
- Arthroeroesis screw: A special screw is placed between the talus and calcaneus in an area called the sinus tarsi, and this blocks abnormal eversion (‘kicking out’) of the heel seen in flat feet.
- Spring ligament repair. This is a sling-shaped supportive ligament in the arch of the foot which often tears as part of the disease process.
- Arthrodesis: In cases where arthritis has developed, the bones are re-aligned and fused to stabilise the hindfoot and prevent the condition from progressing further.