What is a degloving injury of the hip?

What is a Degloving Injury to the Hip

A degloving injury to the hip is a closed soft-tissue injury where traumatic shearing forces separate the skin and subcutaneous tissue from the underlying fascia, creating a potential space that fills with blood, lymphatic fluid, and liquefied fat—most commonly occurring over the greater trochanter and known as a Morel-Lavallée lesion when located in this region. 1, 2

Mechanism and Pathophysiology

• The injury results from high-velocity tangential or shearing forces that disrupt the perforating vessels between the skin and deep fascia, creating an internal degloving without external skin disruption 2, 3
• The thigh, hip, and pelvic region are the most commonly affected locations, particularly over the greater trochanter, though it can also occur in the flank and lumbodorsal regions 2, 3
• The separated tissue layers create a cavity that accumulates hematoma and liquefied fat, which can become a nidus for bacterial colonization even in the absence of an open wound 3

Clinical Presentation

• Patients typically present following high-energy trauma such as motor vehicle accidents, with the injury often occurring when the body is forcefully compressed against a hard surface 1, 2
• The lesion may be easily missed or have delayed diagnosis because distracting injuries in polytrauma patients can obscure the soft-tissue injury 2
• Physical examination reveals a fluctuant mass or contour deformity over the affected area, though early presentations may show only subtle swelling or ecchymosis 1, 2

Diagnostic Imaging

• MRI is the gold standard for characterization and classification of these lesions, showing the fluid collection between tissue planes and helping determine the age and extent of the injury 1, 2
• Ultrasound can identify the fluid collection and is useful for initial diagnosis and guiding percutaneous drainage procedures 4

Critical Management Considerations

• Bacterial colonization occurs in 46% of cases regardless of time from injury to treatment, making these lesions high-risk for perioperative infection if associated fractures require surgical fixation 3
• Early drainage and debridement is crucial to prevent complications including recurrent fluid accumulation, infection, chronic pain, and pseudocyst formation 1, 4, 2
• The injured soft tissues should be debrided either before or at the time of any fracture fixation, with wounds left open and repeated surgical debridement recommended rather than primary closure 3

Common Pitfalls

• Misdiagnosis as a simple contusion or hematoma delays appropriate treatment and significantly increases complication rates 4
• Primary closure over drains leads to chronic deep soft-tissue infections requiring multiple subsequent debridements 3
• Failure to recognize the injury before pelvic or acetabular surgery increases the risk of deep bone infection, as the expanding hematoma compromises skin vascularity and creates an infected field 3