ARRS 2022 Abstracts


E2012. Proximal Tibiofibular Joint: The Forgotten Joint of the Knee
  1. Hanna Tomsan; Mercy Catholic Medical Center
  2. Jeffrey Poot; Mercy Catholic Medical Center
  3. Justin Mackey; Mercy Catholic Medical Center
  4. Reza Hayeri; Mercy Catholic Medical Center
The proximal tibiofibular joint is a unique articulation with complex anatomy and the site of attachment for multiple ligaments. In the presence of communication with the knee joint, it may be considered the fourth compartment of the knee. Disorders of this joint can be the cause of lateral knee pain. Due to a lack of emphasis in the current literature, proximal tibiofibular joint pathology is often overlooked on imaging. This articulation is usually in the FOV of most knee imaging studies, so careful evaluation of this area is particularly important in cases of lateral knee injury and pain. In this pictorial review, we will describe the anatomy, biomechanics, and spectrum of traumatic and non-traumatic conditions involving this joint. We will also review some common conditions in the posterolateral knee corner affecting the proximal tibiofibular articulation. Familiarity with these entities will contribute to correct diagnosis and management.

Educational Goals / Teaching Points
The goals of this exhibit are as follows. Review the normal anatomy, types of articulation, and biomechanics of the proximal tibiofibular joint. Discuss the associated synovial, myotendinous, and ligamentous structures. Demonstrate the imaging features of congenital, degenerative, infectious/inflammatory, and neoplastic disorders, affecting the proximal tibiofibular joint. Illustrate the spectrum of injuries of the proximal tibiofibular joint, including posterolateral instability, adjacent posterolateral knee corner trauma, and nerve injury. Provide examples of normal postoperative appearances of the proximal tibiofibular articulation.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
In this case-based educational exhibit, we will review the radiographic, CT, and MRI appearance of traumatic and nontraumatic pathology of the proximal tibiofibular joint with particular attention to underlying disease mechanisms. We will provide a concise review of normal anatomy and biomechanics around the proximal tibiofibular articulation. We will also discuss the role of different imaging modalities and the use of dedicated MR protocols in the diagnosis of these conditions.

The proximal tibiofibular joint is a frequently neglected but important piece of anatomy that can be a source of lateral knee pain. The knowledge of normal anatomy, biomechanics, and the broad spectrum of entities affecting this joint is the prerequisite for correct imaging interpretation. The purpose of this exhibit is to provide a comprehensive pictorial review of traumatic and nontraumatic conditions affecting the proximal tibiofibular joint, to ensure accurate diagnosis and guide appropriate treatment.