Case of the Month - October 2020

Proximal Tibiofibular Joint Instability

Case: 20-year-old female college soccer player with noncontact injury to her knee playing soccer. No knee swelling or perceived instability. No prior knee symptoms. Her main issue was recurrent lateral sided knee pain with running and cutting. Differential diagnosis included proximal tibiofibular joint (PTFJ) injury, lateral meniscus tear, fibular collateral ligament (FCL) injury, biceps femoris pathology, and IT band syndrome. She demonstrated symptomatic laxity of the proximal tibiofibular joint on exam with translation of the fibular head that completely recreated her symptoms. She failed therapy, diagnostic injection, anti-inflammatory medication and activity modification. Her symptoms while running were completely relieved with posteriorly directed taping of her fibular head. Her symptoms quickly returned when not taping. We performed an anatomic proximal tibiofibular joint reconstruction with hamstring autograft. Four-months post-op and the patient has no symptoms and is making a great recovery.

Intraoperative video of proximal tibiofibular joint instability prior to reconstruction.

Instability of the proximal tibiofibular joint is a rarely reported condition. The vast majority of PTFJ instability occurs in an anterolateral direction. Patients with PTFJ subluxation often have no history of inciting trauma or injury, and many patients have bilateral symptoms and generalized ligamentous laxity. Unilateral injuries can occur in patients without predisposing factors and are associated with a traumatic event such as a motor vehicle accident or athletic injury. Initial treatment is conservative and includes fibular head taping, which serves both diagnostic and potentially therapeutic benefit. Indications for surgery include chronic PTFJ instability failing nonoperative treatment, dysesthesia due to common peroneal nerve irritation and acute PTFJ dislocation not reducible by closed means.

Intraoperative Image on lateral knee incision. Common peroneal nerve (star).

Post-operative video of stable proximal tibiofibular joint following reconstruction.

Post-op X-rays following proximal tibiofibular ligament reconstruction.