Morel-Lavallée Lesion of the Knee in a Recreational Frisbee Player

Abstract

Traumatic swelling/effusion in the knee region is a relatively common presenting complaint among athletes and nonathletes. Due to its broad differential diagnosis, a comprehensive evaluation beginning with history and physical examination are recommended. Knee joint effusion can be differentiated from other types of swelling by careful physical examination. Imaging, including plain radiography, ultrasound, and magnetic resonance imaging (MRI), is preferred modality. Aspiration of a local fluctuating mass may help with the diagnosis and management of some of these conditions. We present a case of a 26-year-old gentleman with superomedial Morel-Lavallée lesion (MLL) of the knee with history of a fall during a Frisbee game. His MLL was successfully treated with therapeutic aspiration and compression wrap without further sequelae. MLL is a rare condition consisting of a closed degloving injury caused by pressure and shear stress between the subcutaneous tissue and the superficial fascia or bone. Most commonly, MLL is found over the greater trochanter and sacrum but in rare cases can occur in other regions of the body. In most cases, concurrent severe injury mechanisms and concomitant fractures are present. MLL due to sports injuries are very rare. Therapeutic strategies may vary from compression wraps and aspiration to surgical evacuation.

Practical Review of the Comprehensive Management of Morel-Lavallée Lesions

“…Sports-related MLLs with these same mechanisms are described in a number of series and case reports. 7–12…”

Morel‐Lavallee Lesions of the Knee: Update and Imaging Review

“…Most publications are case reports or small case series. 8,[10][11][12][13][14] This may be due in part to the broad differential diagnosis for causes of knee soft tissue swelling, resulting in underdiagnosis. For instance, bursitis may mimic a degloving fluid collection.…”

“…Literature on MLLs of the knee is relatively sparse compared to other regions in the body. Most publications are case reports or small case series 8,10‐14 . This may be due in part to the broad differential diagnosis for causes of knee soft tissue swelling, resulting in underdiagnosis.…”

Morel‐Lavallee injury a case study

“…The differential diagnosis may present as challenging from a physical examination standpoint, as many of the presenting signs overlap. Morel‐Lavallee lesions are frequently misdiagnosed . With a thorough history, a fluid collection in a typical location and a strong clinical suspicion, the diagnosis of Morel‐Lavallee lesion is likely .…”

“…Morel-Lavallee lesions are frequently misdiagnosed. 13 With a thorough history, a fluid collection in a typical location and a strong clinical suspicion, the diagnosis of Morel-Lavallee lesion is likely. 6 Ruptured bursa would occur as a fluid collection in a known anatomic location, and the Morel-Lavallee lesion is usually distal to joints.…”