Morel-Lavallée Lesion in a Patient With Metformin-Induced B12 Deficiency: A Rare Complication Following a Fall

Abstract

A Morel-Lavallée lesion (MLL) is a type of closed injury resulting in the internal shearing of superficial skin and subcutaneous tissue from the underlying fascial layer, usually occurring after traumatic accidents such as sports injuries or motor vehicle accidents. In this case, a 68-year-old man developed an MLL as a complication following a moderate-impact fall due to metformin-induced vitamin B12 deficiency. A known complication of metformin use is vitamin B12 deficiency, but this is often underdiagnosed due to a lack of routine screening. This case illustrates the importance of being aware of this complication and the many roles of vitamin B12 in terms of its effects on balance, proprioception, blood vessel integrity, and wound healing, emphasizing the importance of routine vitamin B12 screening in metformin users.

Keywords: lower limb wounds; metformin therapy; morel-lavallée lesion (mll); types 2 diabetes; vit b12 deficiency.

Figure 1. Noncontrast CT-Cross-Sectional View of the Right Thigh

CT image revealing a deep subcutaneous fluid collection measuring 6.6 x 3.5 cm, with the arrow at the interface of the deep fascia and adjacent tensor fascia lata muscle. Overall, this lesion is consistent with an MLL due to the location of the lesion being between the fascia and overlying subcutaneous fat.