Morel Lavallee lesion is a common swelling resulting from trauma. Common sites include the outside hip and thigh. How do we manage a morel-lavallee lesion, and do you need it drained?
What is a Morel Lavallee lesion?
Morel Lavallee lesion is swelling between the bottom part of the skin dermis and the fascia. Usually, trauma or a fall leads to a shearing force on the soft tissue. This leads to breakage of the blood and lymph vessels and blood collection between the skin fat and the facia. If left untreated, this fluid becomes a little more complex as the body tries to get rid of this fluid.
How to make a correct diagnosis
Morel Lavalle Lesion appears after trauma such as a fall from a bicycle. Generally, the trauma involves a shear force to the area that makes contact with the ground. The lesion can appear immediately or after a few days. Sometimes, other injuries can occur, including fractures of the pelvis or the hip, but not always.
Usually, we see swelling, bruising, and skin laxity. As the fluid gets bigger, it can become stiff and painful. Sometimes, the fluid can become infected, leading to redness and heat.
The most common sites are outside the hip or the top part of the thigh. However, we also see lesions in the low back, front of the knee, or shoulder blade.
Morel Lavalle lesion radiology
Generally, most cases are confirmed by clinical examination. However, imaging can confirm the fluid-filled pockets superficial to the fascia.
Often, ultrasound or MRI can show the fluid-filled pockets clearly. In addition, imaging can define the age of the lesion, either acute or chronic, and rule out other injuries (such as fractures or muscle/tendon tears)
Difference between haematoma and Morel Lavallee lesion
Of course, not all swelling at the hip or thigh is a Morel Lavalle lesion. Often, a muscle haematoma can present with similar swelling and bruising. However, the swelling in a haematoma is deep in the muscle rather than above the muscle. Often, one way of telling between the two conditions is the absence of skin laxity in muscle haematoma.
Other possible causes of swelling in the hip or thigh include fat necrosis, early myositis ossificans or a tumour.
Complications of Morel Lavallee lesion
Most lesions will settle without problems. However, in some cases, treatment does not go smoothly. Adverse effects include repeated swelling, infection, significant scar tissue formation and other co-existing injuries.
Morel Lavallee lesion management
Generally, smaller lesions can be managed with ice and compression. However, larger lesions should be aspirated to prevent infection. Typically, we combine the aspiration with ice and compression to prevent the lesion from returning. A recent study found that repeated aspiration combined with reduction, ice and physiotherapy resolved most cases.
Usually, we perform aspiration using ultrasound guidance to remove the fluid altogether. It is crucial to perform this procedure with strict sterility to prevent infection. Greater than 50mls of aspiration means that recurrence rates are higher.
Sometimes, we inject a sclerosant, such as high-concentration dextrose (sugar), to encourage scar tissue formation and prevent recurrence. Some practitioners use tetracycline or doxycycline (a type of antibiotic). We recommend sclerosants in cases with higher aspiration volumes (50mls or greater).
Occasionally, we consider surgery for extensive lesions with high volumes (greater than 80mls), lesions that form a capsule, or lesions associated with other injuries.
Other frequently asked questions about Morel Lavalle lesions:
When should you consider drainage of a Morel Lavalle lesion?
Large lesions that cause cosmetic concern or look unappealing should be drained. If an extensive lesson is not drained, resorption is slow and can take many months.
What is the recurrence rate after drainage of a Morel Lavallee lesion?
It’s hard to know the exact recurrence rate based on data. Overall, recurrence rates range from 0-75%. In one study, greater than 50mls of aspiration meant a much higher recurrence rate (than a lower aspiration volume (32%).
Is pain a feature of a Morel Lavallee lesion?
Initially, mild to moderate pain is a feature of direct trauma. However, symptoms quickly settle over days to a few weeks. Intractable or severe pain after 3-4 weeks is uncommon for a Morel-Lavallee lesion. Low-level pain may be a feature secondary to chronic inflammation in long-standing cases. For these cases, we consider a low-dose cortisone injection into the interface after ensuring infection is excluded. For severe pain not due to another cause, we need to consider infection.
Final word from Sportdoctorlondon regarding Morel Lavallee lesion
Morel Lavallee lesions form after a shearing force or trauma to the hip or thigh. Most cases in sports or after minor trauma involve small amounts of fluid. Generally, we treat these lesions conservatively with ice, compression and repeated aspiration. Large aspiration volumes mean a higher recurrence rate, suggesting more aggressive treatment with sclerosants.
My husband has this injury from a 4wheeler accident. He had multiple wash out procedures, but nothing helped and he developed an infection. It took a sclerosing procedure using doxycycline to help him. It has been 3 weeks since his most recent surgery, and it appears as though it is finally starting to heal. For reference, the accident occurred August 11, 2024 and it is now November 30th
thanks Mel for your comment. yes we use sclerosants such as high concentration dextrose but tetracycline or doxycycline (a type of antibiotic) can also be used. And yes we need to consider infection in some cases particularly for large swelling or increasing pain.
Lorenzo