Background: Morel-Lavallée lesions (MLLs), also known as degloving injuries, are uncommon traumatic soft tissue injuries resulting from the separation of the superficial fascia from the deep fascia, typically due to high-energy trauma or shear forces. This separation leads to fluid accumulation and disruption of skin vascularity, placing the overlying skin at risk for necrosis and infection. MLLs can mimic other soft tissue injuries, such as hematomas, and are often associated with delayed diagnosis and treatment. Case Presentation: A 46-year-old man presented with left thigh swelling persisting for three weeks following a motorcycle crash. Initial imaging with X-rays revealed no fractures, and point-of-care ultrasound identified a large encapsulated fluid collection consistent with MLL. Subsequent computed tomography angiography ruled out vascular injury and confirmed a subcutaneous fluid collection measuring 10.6 cm × 32.0 cm. Conservative management, including compression bandaging and prophylactic antibiotics, was initially recommended; however, after surgical review, ultrasound-guided drainage was performed to mitigate the risk of skin necrosis. The patient recovered uneventfully and was discharged 48 hours after the procedure. Conclusion: This case highlights the importance of maintaining a high index of suspicion for MLLs in patients with post-traumatic swelling, even in the absence of fractures or significant injuries. Accurate diagnosis and timely intervention are essential to reduce the risk of complications. Point-of-care ultrasound and computed tomography are valuable diagnostic tools in emergency settings, particularly for patients with contraindications to contrast agents. Future guidelines should emphasize clinical vigilance and the role of advanced imaging in managing MLLs effectively.

Keywords: Morel-Lavallée lesion, degloving injury, traumatic soft tissue injury, point-of-care ultrasound (POCUS), computed tomography angiography.