The Hidden Meniscal Flap Tear: Don’t Miss It

Austin V. Stone, MD, PhD^1* & Bernard R. Bach Jr, MD²

¹Division of Sports Medicine, Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky, USA
²Division of Sports Medicine, Department of Orthopaedic Surgery, Rush University Medical Center, USA

Dr. Austin V. Stone, MD, PhD, Division of Sports Medicine, Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky, Lexington, KY, USA.

Keywords: Meniscus Tear; Flap Tear; Knee Arthroscopy; Meniscus; Osteoarthritis

Abstract

Background
Meniscal tears are an extremely common pathology. Patients may experience mechanical symptoms such as locking and catching with joint line pain. Arthroscopic partial meniscectomy is used to treat symptomatic tears that are refractory to conservative management. A certain type of meniscal tear, the hidden-flap tear, can be missed if not carefully evaluated.
Case Description
The patient was a 53-year-old female with anteromedial knee pain for three months. The pain was more anterior than classic meniscal tears. Her radiographic imaging was consistent with a medial meniscus tear with an incarcerated flap in the medial gutter. At the time of the arthroscopy, the meniscus appeared “auto-meniscectomized” and careful evaluation and reduction was necessary to fully treat the pathology. She experienced immediate pain relief post-operatively.
Literature Review
Meniscus tears are frequently encountered and most commonly are readily identifiable with knee arthroscopy. A lesser characterized tear is the meniscal flap tear with incarceration in the gutter. These tears were originally described as more commonly superiorly displaced, but recent radiographic evaluations have reported more common inferior displacement. The classic pain symptoms associated with these tears is posteromedial at the middle third and posterior third junction.

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).