What is Morel Lavallee Lesion?
A Morel-Lavallee lesion is a specific type of injury, first identified in 1863 by a French surgeon named Maurice Morel-Lavallee. It’s a form of internal damage that happens after a significant trauma, where the inner layer of skin separates from the deeper tissues, creating a space in between.
When a severe injury takes place, the surrounding blood vessels and lymph nodes can be damaged, leading to a buildup of blood and lymph fluid in this created space. This triggers a chronic inflammatory response in the body, in which, over time, a walled-off lesion or injury may form. This wound is typically filled with deteriorated fatty tissue, blood components, protein involved in blood clotting (fibrin), and other cellular debris.
Someone with a Morel-Lavallee lesion usually experiences a painful, fluid-filled swelling at the site of the injury. In medical literature, this lesion is occasionally referred to as a Morel-Lavallée seroma, posttraumatic soft tissue cyst, post-traumatic extravasation, or Morel-Lavallée effusion. It’s important to note that this type of injury can sometimes go unnoticed at the time of initial evaluation. The lesion can emerge later, making it more difficult to manage and potentially leading to long-term health issues.
What Causes Morel Lavallee Lesion?
Morel-Lavallee lesions are often caused by severe injuries such as hard and fast impacts, crushing injuries, and blunt force traumas like what might happen in a car crash. In fact, about a quarter of all people who get Morel-Lavallee lesions were in a car accident.
This type of injury is frequently found in combination with broken bones, particularly in the upper part of the thigh bone, the pelvis, and a part of the hip bone called the ‘acetabulum’. Over sixty percent of Morel-Lavallee cases involve the greater trochanter, a prominent part of the thigh bone.
There are some factors that make a person more likely to get a Morel-Lavallee lesion. One is that the femur, or thigh bone, is located close to the surface of the skin and has a large surface area. This, along with strong underlying tissue called the tensor fascia lata and the movement of the skin, increases the risk.
Other factors include having a body mass index (the measurement of body fat based on height and weight) of 25 or greater. Less common locations for these injuries include the buttocks, the shoulder blade region, the lower back and torso. Some people may also develop Morel-Lavallee lesions due to sports injuries directly to the knee.
In very rare instances, Morel-Lavallee lesions have been reported after surgical procedures like tummy tucks or liposuction.
Risk Factors and Frequency for Morel Lavallee Lesion
This particular injury, which affects the hip joint, isn’t seen very often in medical practice. It’s found in about 8.3% of people who have had a hip fracture. It tends to occur more often in males, with roughly two males affected for every female. This could be because males generally have more multiple injuries at the same time. But it’s important to note that this injury often goes unnoticed or isn’t recognized until a later stage, so in reality, it might be more common than we think.
Signs and Symptoms of Morel Lavallee Lesion
The Morel-Lavallee lesion is often linked to a previous injury or trauma. Interestingly, about 33% of people with this condition don’t show symptoms right away, presenting them later on. The lesion often appears as a swelling that grows over time, potentially causing pain and a feeling of tightness.
Certain characteristics help doctors diagnose a Morel-Lavallee lesion, such as its feel, specifically fluctuation and compression, and how the person’s symptoms correlate with their medical history.
These lesions might also resemble a bruise or injury to a certain area. People with Morel-Lavallee lesions might also experience reduced skin sensitivity or even numbness due to damage to the nerves beneath the skin. Additionally, the skin may move more easily than usual. Changes in the skin, such as discoloration, cracking, drying, scrapes and even dead tissue, may be observed as well.
It’s not uncommon for these lesions to reappear, especially after treatments that are less invasive.
Testing for Morel Lavallee Lesion
In cases of severe body injuries, especially around the hip area, doctors should check for a type of injury called Morel-Lavallee lesion. It is often discovered during surgery for other fractures, but can sometimes be identified on early images taken when the patient first arrives to the hospital.
Usually, this injury is identified during a physical examination. If it’s not clear whether the injury is present, imaging methods can help confirm. Magnetic Resonance Imaging, or MRI, is often the best method. The MRI can show many details of the injury, such as its size, shape, what it contains, and whether it is a new or old injury. However, most of the time, an MRI is not needed for diagnosis purposes.
The appearance of the lesion varies depending on whether it’s new or old. If it’s been there for a while, it usually appears smooth and even. If it’s a new injury, it appears uneven and irregular. With older injuries, a capsule forms around the wound, making it appear as a dark ring with tissue components. The edges of the lesion fade and blend with the surrounding tissue layers.
Ultrasonography, also known as an ultrasound, is less useful for this injury, but can help confirm the depth of the lesion – if it’s located between the skin and the muscle layer. It also can show whether the lesion is pressable and helps rule out the presence of blood flow in the lesion, thus ruling out other possible conditions. Computed tomography (CT scan) is rarely beneficial for this type of injury, especially in determining other possible conditions.
Experts have proposed classification systems for Morel-Lavallee lesions. One system categorizes the lesion into six types based on the injury’s appearance, MRI characteristics, and the presence of a capsule around the wound. While this helps categorize the lesions, it doesn’t provide any guidance on treatment or possible outcomes. Another proposed system simplifies the lesion into two categories – acute and chronic, based on the presence of a capsule. This system can help predict the treatments and potential outcomes.
Treatment Options for Morel Lavallee Lesion
Currently, there are no specific guidelines on how to manage Morel-Lavallee lesions – injuries that happen when skin separates from the underlying tissues, much like a deep bruise. Numerous studies with varying levels of evidence have shown mixed results for several treatment methods. These include conservative management (which is a hands-off approach), injections that cause inflammation and healing (sclerodesis), draining the fluid from the lesion (percutaneous aspiration), and even open surgery.
The conservative management approach can work for small, recent Morel-Lavallee lesions that don’t have a hardened outer layer, known as a capsule. This treatment typically includes applying compression bandages to reduce swellings. However, this approach is generally not appropriate for chronic (long-standing) cases or larger lesions, which usually require surgical intervention.
Draining the fluid from the lesion using a needle and a syringe (percutaneous aspiration) can sometimes be effective, but there tends to be a high chance that the lesion will return. This problem is particularly common in lesions that contain more than about 1.7 fluid ounces, and such lesions often require repeated draining.
Another treatment option for Morel-Lavallee lesions is called sclerodesis, particularly when draining doesn’t serve its purpose. This technique uses drugs that inflame the area around the lesion, causing scar formation. Commonly used drugs for this method include doxycycline, erythromycin, vancomycin, tetracycline, bleomycin, absolute ethanol, and talc. About 96% of treatments using sclerodesis are successful according to reports.
A lot of the time, Morel-Lavallee lesions require an open surgery for cleansing the wound and removing the pseudocapsule – a kind of false outer layer – that forms around old lesions. The ultimate goal of managing Morel-Lavallee lesions is to avoid having a void space in the site of the wound, which can be achieved through techniques like applying a fibrin sealant, special stitches, and low suction drains. This can be done either through a single long or multiple small incisions when the skin over the lesion is healthy. However, if the skin over the lesion is dead (necrotic), it must be removed and the soft tissue reconstructed. In certain cases where even open drainage doesn’t work, the entire lesion may need to be removed with its capsule.
What else can Morel Lavallee Lesion be?
When a doctor is trying to diagnose a Morel-Lavallee lesion, they may also consider these conditions:
- Post-operative seroma: fluid-filled sac that can appear after surgery
- Coagulopathy-related hematoma: an abnormal clotting condition that can cause bleeding and bruising
- Fat necrosis: a condition where fatty tissue is damaged by injury
- Early-stage myositis ossificans: a condition where muscle tissue hardens into bone after injury
- Diffuse subcutaneous edema: swelling caused by fluid accumulation under the skin
These conditions can appear similar to a Morel-Lavallee lesion both clinically and on medical imaging, which can make diagnosis challenging. A patient’s history of prior injury can play an important role in making the correct diagnosis.
What to expect with Morel Lavallee Lesion
The outcome of Morel Lavallee lesions, which are internal injuries that contain liquid or fat, can depend on a number of things. Small, fresh injuries of this type often heal on their own without the need for surgery, so they typically have a very good outcome.
However, larger injuries of this type can pose a risk, particularly after surgery. This is because they can increase the risk of infection at the site of any associated bone injuries received during surgery. These larger injuries can also impact when and how surgeons choose to manage any related orthopedic injuries.
If these lesions persist and become chronic, a pseudocapsule, which is like a false shell, can form around the lesion. This can then prevent the body from absorbing the contents of the lesion, leading to unwanted complications and a poorer outcome.
Possible Complications When Diagnosed with Morel Lavallee Lesion
The complications associated with Morel-Lavallee lesions are primarily due to delayed recognition of the problem or inaccurate diagnosis. If not correctly treated, the lesion can continue to grow, eventually causing the skin above it to die due to the pressure. This can leave any fractures beneath it exposed. Infections are also a significant risk with Morel-Lavallee lesions. There have been numerous studies noting that these lesions can often be contaminated. This contamination can occur when micro-organisms unintentionally get into the lesion while it’s being treated, particularly when certain agents to close off blood vessels are used, or while an underlying fracture is being fixed.
Complications to note:
- Gradual progressive expansion of the lesion
- Skin above the lesion dying due to pressure
- Exposure of underlying fractures
- Potential infection
- Contamination of the lesion
Preventing Morel Lavallee Lesion
If you have injuries from a high-speed accident, particularly in your hip or pelvis, pay close attention and let your doctor know if you notice any swellings near the injury. Your treatment may require a small tube to be inserted into the wound for about two weeks to help it heal. Your doctor will explain this to you to make sure you understand and agree with this part of the treatment.
The less invasive option of percutaneous aspiration, which is a procedure to remove excess fluid with a needle, has a higher chance of the problem coming back. So, your doctor will give you all the necessary information before you decide on a more invasive debridement. Debridement is a procedure that involves opening up the wound to clean out damaged or infected tissue.
After your treatment, the right rehabilitation and physical therapy are essential for the best healing and a smooth return to daily activities. This is important whether you’ve had surgery or non-surgical treatment for your injuries.