Adolescent Morel-Lavallée Lesions: A Case Report of Challenges in Diagnosis and Management in Atypical Locations.

BACKGROUND Morel-Lavallee lesions (MLLs) are uncommon, closed soft-tissue degloving injuries caused by high-energy trauma that are often missed due to their rarity and delayed presentation, resulting in serious complications. MLLs are particularly missed and underreported in pediatric and adolescent patients. We describe the case of an adolescent MLL occurring in an atypical lesion site at the calf to increase awareness of this diagnosis and associated presentation in this patient group, which can differ from adult presentation and contribute to diagnostic uncertainty that consequently impacts clinical decision-making. CASE REPORT An 18-year-old male presented with pain and worsening swelling in the right lateral calf after sliding into a wall while playing basketball. Magnetic resonance imaging (MRI) demonstrated a fluid collection initially suspected to be a hematoma. Following failed conservative management, a multidisciplinary collaborative approach confirmed a MLL diagnosis and drained the lesion via ultrasound-guided aspiration. While the patient has resumed all normal physical activities, residual swelling and deformity remain under surveillance. CONCLUSIONS Our case highlights the diagnostic and treatment challenges associated with an atypical clinical presentation of a MLL in an adolescent patient with a sports injury to the calf, highlighting the role of imaging and multidisciplinary consultation in timely intervention. Consistent with the limited existing literature on MLLs, early minimally invasive ultrasound-guided aspiration may be beneficial to guide subsequent treatment, but further study and consensus via establishment of standardized pediatric and adolescent management guidelines are necessary to achieve optimal clinical outcomes for this vulnerable patient population.