THE MOREL LAVALLEE LESION: HOW POCUS CHANGE PATIENT’S DISPOSITION

Abstract

Introduction

The Morel-Lavallee lesion is a rare cause of knee pain following trauma. It is a closed degloving injury between the hypodermis and underlying fascia caused by shearing or crushing forces.  Subsequently, vascular and lymphatic structured are disrupted which cause blood, lymph and necrotic tissue to accumulate between these two tissue layers.

Case Report

A 20 years old obese gentleman presented to our district emergency department with worsening left knee swelling and pain following road traffic accident, one week prior to the presentation. He already visits other healthcare facilities twice, where xray was done which was negative for fracture. During previous visit, he was discharged with analgesic and given nearest orthopaedic follow-up.

During this current presentation, his left knee was swollen with tenderness all over especially at the pre-patellar area. Repeated xray show no obvious fracture. Bedside ultrasound (POCUS) was done which show large collection within the subcutaneous layer in pre-patellar region. The patient was diagnosed as Moralle lavelle lesion (internal degloving of the left knee), referred to orthopaedic tertiary centre for admission and further evaluation.

During the course of admission, he underwent surgical operation twice. He was discharged well after one week of admission. During follow up one week later, he able to ambulate which he regain full range of motion of left knee.

Discussion and conclusion

Diagnosis of Morel-Lavalle lesion can be challenging, especially in the knee where the most common location for this lesion are thigh and pelvis. Magnetic resonance imaging would be the imaging modality of choice, but still like in this case, ultrasonography also can be done to diagnose the lesion. Delay in diagnosis can lead to many complications, such as infection, pseudocyst and cosmetic defect. Awareness of this diagnosis by emergency physician is crucial in the differential diagnosis of traumatic knee pain.