Morel-Lavallée Lesion: AIRP Best Cases in Radiologic-Pathologic Correlation

The Morel-Lavallée Lesion: Review and Update on Diagnosis and Management

Morel-Lavallée lesion is a closed soft tissue degloving injury usually associated with high-velocity trauma. It most commonly occurs in the thigh, hip, and pelvis. Because such lesions are prone to a missed or delayed diagnosis, it may present a potential risk of infection at the fracture site once it progresses. Therefore, timely identification and management of Morel-Lavallée lesion is crucial. Moreover, there are no relevant guidelines for the treatment of Morel-Lavallée lesion. Based on the above facts, we reviewed the etiology, epidemiology, pathophysiology, clinical presentation, imaging features, treatment, prognosis, and complications of Morel-Lavallée lesion with the aim of providing a comprehensive overview of Morel-Lavallée lesion, increasing awareness of this injury among orthopaedic surgeons, and thus providing a management algorithm that can be applied to this injury.

Imaging of Muscle Injuries

Ultrasound (US) and MR imaging are the most common imaging modalities used to assess sports muscle injuries. The site of the muscle injury can be located at the peripheral aspect of the muscle (myofascial), within the muscle belly (musculotendinous), and with tendon involvement (intratendinous). Tears that affect the intramuscular tendon have a worse prognosis in terms of recovery time. US is an excellent method to evaluate muscle injuries, with high spatial and contrast resolution. MR imaging can be reserved for evaluation of professional athletes, surgical planning, differential diagnosis, and assessment of deep located and proximal muscle groups.

The treatment of a Morel-Lavallée lesion of the thigh with incision and drainage along with tissue debridement and a surgically placed drain: A case report and literature review

Background

A Morel-Lavallée lesion (MLL) is a rare closed degloving injury that usually occurs around the hips and is associated with pelvic fractures after high-energy trauma, which is commonly overshadowed by other severe post-traumatic manifestations. An isolated MLL, mostly caused by low-energy violence, is even rarer. Thus, the rates of misdiagnosis and missed diagnosis are often high. In this case report and literature review, we review the pathophysiology, clinical manifestations, imaging data, and treatment of this lesion to increase awareness of this rare disease.

Case report

We report the case of an isolated MLL in the right thigh caused by trauma, which happened to be one of missed diagnosis both at the initial visit and at the return visit of the patient, with a significant sign of a mass on MRI. Given the size of the lesion, open debridement and irrigation were adopted to treat the lesion, and the patient recovered well post-operatively.

Conclusion

Young surgeons should pay attention to the MLL with sufficient recognization to avoid missed diagnosis and misdiagnosis. Comprehensive physical examination and imaging data play important roles in the diagnosis of MLL. In the early stages of this injury, a detailed history review combined with physical examination and MRI, can reduce the rates of missed diagnosis and misdiagnosis. The choice of the therapeutic scheme depends on the size and severity of the lesion. For an isolated MLL, compared with conservative treatments, we suggest that incision and drainage, along with tissue debridement and a surgically placed drain, will reduce the rates of infection and recurrence.

Ten-year incidence and treatment outcomes of closed degloving injuries (Morel-Lavallee lesions) in a level 1 trauma centre

INTRODUCTION

Morel-Lavallée lesions (MLL), also referred to as closed degloving injuries, result from traumatic shearing forces with separation of the subcutaneous fat from the underlying fascia. The aim of this study was to determine the incidence and treatment of MLLs at a level 1 trauma centre.

METHODS

Single-centre retrospective cross-sectional study of consecutive patients with an imaging diagnosis of a Morel-Lavallee lesion from 1/1/2010-31/12/2019. Demographic data, mechanism of injury, volume of lesion, management and outcome data were collated.

RESULTS

Sixty-six MLLs were identified in 63 patients (64% Male) with a median age of 49.5 years (19-94 years). Mechanism of injury were road traffic accidents in the majority (66%). Median injury severity score (ISS) was 17 (range 1-33). Patients on oral anti-coagulants had significantly larger lesions (181.9 cc v 445.5 cc, P = 0.044). The most common lesion location was the thigh (60.5%). Patients that underwent imaging within 72 h of injury had significantly larger lesions than those imaged more than 72 h after the inciting trauma (65 cc v 167 cc, P < 0.05). Management data were documented in 59% of lesions (39/66) in which 66.6% (n = 26) had invasive treatment. In the 31 patients where follow-up was available, 64.5% (n = 20) were persistent but decreasing in size. There was no significant difference in follow-up size for those who had invasive compared to conservative treatment (P = 0.3).

CONCLUSION

The diagnosis of MLL should be considered for soft-tissue swelling in the context of shearing trauma. A variety of management options have been employed, with good overall outcomes.

Morel-Lavallée Lesion of the Elbow Region ‎in a Young Male: Case Report and ‎Literature Review

The Morel-Lavallée lesion is a fluid collection resulting from the traumatic separation ‎of the ‎subcutaneous tissue from the underlying fascia. It frequently occurs over the trochanteric ‎region but ‎may also occur in the flank, lumbosacral region, and buttock. Morel-Lavallée lesions ‎in the upper limb are rarely reported in the literature.‎

In this report, we present a case of a 42-year-old male, not known to have ‎‎any medical ‎diseases, who suffered from a post-traumatic left elbow mass that had existed for seven months before his presentation to our clinic. It is worth reporting this case to increase the awareness of ‎this little-known pathology among orthopedic surgeons. In addition, most of the Morel-Lavallée ‎lesions mentioned in the literature are located in the lower limb.‎

Practical Review of the Comprehensive Management of Morel-Lavallée Lesions

Morel-Lavallée lesions have been described in the literature since the mid-19th century, yet contemporary clinical management continues to be challenging and remains variable. These closed degloving injuries are usually seen in the setting of blunt trauma and are due to shearing forces, creating a space for the collection of hemolymphatic fluid. These fluid collections can be persistent despite conservative treatment attempts and can require staged surgical interventions.

MRI of the Morel-Lavallée lesion - a case series

INTRODUCTION

The aim of the study was to review the appearances of Morel-Lavallée (ML) lesions on magnetic resonance imaging (MRI).

PATIENTS AND METHODS

14 patients diagnosed with the ML lesion on MRI were analysed retrospectively (mean age = 35 years). Mechanism of injury, time frame from injury to MRI, location, shape, T1 and proton-density fat-suppression (PDFS) signal intensity (SI), presence of a (pseudo)capsule, septations or nodules within the collection, mass effect and fluid-fluid levels were analyzed. The Mellado and Bencardino classification was utilized to classify the lesions.

RESULTS

In most cases, mechanism of injury was distortion. Mean time frame between the injury and MRI was 17 days. Lesions were located around the knee in 9 patients and in the peritrochanteric region in 5 patients. Collections were fusiform in 12 patients and oval in 2 patients. 9 collections were T1 hypointense and PDFS hyperintense. 4 collections had intermediate T1 and high PDFS SI. 1 collection had intermediate T1 and PDFS SI. (Pseudo)capsule was noted in 3 cases. Septations or nodules were found in 4 cases. According to the Mellado and Bencardino, collections were classified as seroma (type 1) in 9, subacute hematoma (type 2) in 1 and chronic organizing hematoma (type 3) in 4 cases.

CONCLUSIONS

Characteristic features of ML lesion include a fusiform fluid collection between the subcutaneous fat and the underlying fascia after shearing injury. Six types can be differentiated on MRI, with the seroma, the subacute hematoma and the chronic organizing hematoma being the commonest.

Endoscopic Resection of Chronic Morel-Lavallée Lesion of the Knee

The Morel-Lavallée lesion is a closed internal soft-tissue degloving injury. About 15.7% of Morel-Lavallée lesions occur in the knee region. Morel-Lavallée lesions are considered chronic when the lesion contains a capsule. The capsule prevents resorption of the fluid content, and the lesion will recur when using conservative treatment alone. Surgical debridement with resection of the capsule is a more definitive treatment option, but it may induce wound complications. In this Technical Note, the technical details of endoscopic resection of chronic Morel-Lavallée lesion of the knee are discussed. This minimally invasive technique has the advantage of better cosmetic results and fewer wound complications.

Lethal Morel-Lavallée lesion: A forensic radiology-pathology correlation

Morel Lavallée lesion or closed degloving injury is normally associated with severe trauma and occurs when the skin and subcutaneous fatty tissue traumatically and abruptly separated from the underlying fascia thus creating a potential space filled with fluid. MVA is the commonest etiology but large or lethal Morel Lavallée is extremely rare. A 35 years old, female pillion rider was involved in a motor vehicle accident and sustained injuries to the left pelvis and thigh. Emergency laparotomy and intra-op abdominal and bilateral lower limb arteriogram revealed no significant finding. Her general condition and vital signs continued to deteriorate despite aggressive resuscitation and eventually died. Post-Mortem Computed Tomography and Post-Mortem Computed Tomography Angiogram was performed and revealed a large cavity in the left thigh suggestive of a lethal Morel Lavallée lesion. Findings were confirmed by conventional autopsy.

Percutaneous Quilting Technique for the Treatment of Morel-Lavallée Lesion

OBJECTIVE

This study looks at the outcome of percutaneous quilting technique for the treatment of closed degloving injuries or Morel-Lavallée lesions (MLL).

DESIGN

Prospective single-centre nonrandomized case series.

PARTICIPANTS

Patients with MLL visiting our hospital between January 2012 and May 2018.

METHOD

The method involves percutaneous single-stage suturing of skin and deep fascia with heavy, non-absorbable, non-braided sutures starting from periphery to centre.

OUTCOME MEASURES

Resolution of the lesion.

RESULTS

Twenty-two patients with MLL treated, which included 18 males and 4 females with an average age of 22 (range 16-52). Lesions varied in length from 12 to 60 cm. The average time gap from the injury to drainage of the lesion was 7 days (range 2-60 days). We followed these cases weekly for 4 weeks and then once a month until 6 months and then at the end of the year. All 22 cases healed uneventfully.

CONCLUSION

Percutaneous drainage along with suturing of the skin and subcutaneous tissue to deep fascia prevents the discordant movement and obliterates the dead space-aiding apposition of the layers. This is a simple and effective procedure with low recurrence rates that addresses the primary pathology of MLL.

LEVEL OF EVIDENCE

Therapeutic level IV.

Morel-Lavellée lesions: MRI characteristics in the pediatric patient

BACKGROUND

A closed degloving injury is often referred to as a Morel-Lavellée lesion regardless of location despite traditionally being associated with the hip in adults. It results from a shearing injury that separates the subcutaneous layers from the fascia with fluid filling a potential space.

OBJECTIVE

While the most common location and cause have been described in adults, there is limited literature in pediatric patients. We have seen pediatric Morel-Lavellée lesions commonly occurring at the knee after sports. We set out to describe the magnetic resonance imaging (MRI) characteristics.

MATERIALS AND METHODS

A retrospective analysis was performed. All patients with trauma to the pelvis and lower extremities with a subcutaneous fluid collection seen on MRI were evaluated. Age, gender, mechanism of injury, time interval to imaging, and treatment were recorded. The collections were evaluated for location, size, shape and signal characteristics including the presence of fat, blood and septations.

RESULTS

Twenty-one patients ages 7 to 17 years old had findings of degloving injury on MRI. The most common etiology was sports related (18/21, 85.7%). The anterior knee was most often affected (18/21, 85.7%). Lesions were ovoid and centered over the medial retinaculum (8/18, 44.4%) or lateral retinaculum (7/18, 38.9%). A capsule was weakly associated with later presentation (P=0.12).

CONCLUSION

Pediatric Morel-Lavellée lesions commonly occur in a location not classically described, the anterior knee, and often after sports injury. Commonly, the collections are ovoid and always located at the subcutaneous fat/fascial interface. Recognition of specific imaging characteristics in a common location after sports injury allows for early identification. While most patients recover with conservative management, some need additional intervention with aspiration or debridement.

Imaging Features of Morel-Lavallée Lesions

Objectives:

To review the imaging characteristics of Morel-Lavallée lesions with both ultrasound and magnetic resonance imaging (MRI).

Materials and Methods:

We retrospectively analyzed 31 patients (mean age = 46 years), diagnosed with a Morel-Lavallée lesion, on ultrasound (n = 15) or MRI (n = 16). On ultrasound the echogenicity, internal septations, hyperechoic fat globules, compressibility and Doppler signal were evaluated. On MRI, T1- and T2-signal intensity, capsule presence, internal septations, enhancement, mass-effect and fluid-fluid levels were assessed. The MR images were classified according to the classification of Mellado and Bencardino.

Results:

Most of the lesions were situated peritrochanteric, around the knee or the lower leg. The majority of the lesions had a heterogeneous hypoechoic appearance with septations and intralesional fat globules. On MRI, most of the collections were hypointense on T1-weighted images and hyperintense on T2-weighted images. Half of the collections were encapsulated, and most collections demonstrated septations. The collections were classified as seroma (n = 10), subacute hematoma (n = 2) and chronic organizing hematoma (n = 5).

Conclusion:

Ultrasound is the imaging method of choice to diagnose Morel-Lavallée lesions. MRI can be of use in selected cases (extension in different compartments, large collections, superinfection). Characteristic imaging features include a fusiform fluid collection between the subcutaneous fat and the underlying fascia with internal septations and fat globules. On MRI, six types of ML lesion can be differentiated, with the seroma, the subacute hematoma, and the chronic organizing hematoma being the most frequently observed lesions.