Bilateral Posterior Tibial Tendon and Flexor Digitorum Longus Dislocations

Area of Science:

• Orthopedic Surgery
• Sports Medicine
• Musculoskeletal Imaging

Background:

• Posterior tibial tendon (PTT) dislocation is a rare injury, often misdiagnosed as a simple ankle sprain.
• Athletes, particularly those involved in high-impact sports, are susceptible to inversion injuries that can lead to PTT dislocation.
• Conservative treatments like immobilization and physical therapy frequently fail to resolve PTT dislocation.

Observation:

• A previously healthy, athletic 17-year-old female presented with a 3.5-year history of medial left ankle pain following an inversion injury.
• Physical examination revealed a dislocated PTT that was temporarily reducible but spontaneously dislocated again.
• Magnetic resonance imaging (MRI) confirmed PTT dislocation, and surgery revealed concurrent dislocation of the flexor digitorum longus (FDL) tendon.

Findings:

• The patient underwent successful suture anchor repair of the medial retinaculum for the left ankle.
• Three months later, she experienced PTT dislocation in the right ankle, also treated with surgical repair.
• At 6 months post-surgery, the patient had full bilateral ankle inversion strength, no PTT subluxation, and returned to all activities without limitation.

Implications:

• This case highlights the importance of considering PTT dislocation in athletes with persistent ankle pain after inversion injuries, even after initial conservative treatment.
• Bilateral PTT dislocation, though rare, can occur and requires prompt diagnosis and surgical intervention.
• Suture anchor repair of the medial retinaculum is an effective treatment for PTT dislocation, leading to excellent functional recovery and return to sport.