From the Trauma Professional Blog
Their experience led them to develop the following practice guideline:
Bottom line: The Morel-Lavallee lesion can be challenging to treat. Although this study has limited numbers, it provides enough guidance to suggest a consistent way of managing it. I recommend adopting this algorithm to provide a standard pathway for dealing with it.
Reference: The Mayo Clinic experience with Morel-Lavallee lesions: establishment of a practice management guideline. J Trauma 76(2):493-497, 2014.