The PITFL is the posterior component of the distal tibiofibular syndesmosis, providing the posterior constraint against fibular diastasis. Its deep component (transverse tibiofibular ligament) contributes to the posterior ankle mortise and can produce a posterolateral impingement in dorsiflexion when torn and healed with scar tissue. The PITFL is identified on axial MRI of the ankle at the posterior syndesmotic level.
| Origin | Posterior tubercle of the distal tibia |
|---|---|
| Insertion | Posterior fibula above the lateral malleolus |
| Actions | Resists fibular external rotation and maintains syndesmotic integrity posteriorly; the transverse tibiofibular ligament runs deep to it |
|---|
PITFL tears occur in syndesmotic ankle sprains alongside AITFL and interosseous membrane injuries. The posterior impingement from PITFL scar tissue produces posterolateral ankle pain during dorsiflexion in athletes — a specific clinical entity managed with arthroscopic scar debridement.
PITFL scar tissue producing posterolateral ankle pain during dorsiflexion in dancers and athletes managed with arthroscopic debridement.
