Endoscopically Assisted Reconstruction of Posterior Tibial Tendon for Stage 2 Posterior Tibial Tendon Dysfunction.

The posterior tibial tendon functions as a primary stabilizer of the medial longitudinal arch of the foot. Posterior tibial tendon dysfunction accounts for 80% of cases of adult-acquired flatfoot deformity. It is classified into 4 stages based on the function of the tibialis posterior tendon, the reducibility of the deformity, and the condition of the ankle joint. The purpose of this Technical Note is to describe the technical details of endoscopically assisted reconstruction of theposterior tibial tendon for stage 2 posterior tibial tendon dysfunction. It consists of using the medial half of the anterior tibialis tendon as a primary transfer and augmentation by the flexor digitorum longus. This construct is then protected with a subtalar arthroereisis.