Concurrent Floating Hip and Open Knee Dislocation: Damage-Control Management

Ipsilateral dislocations of the hip and knee are rare injuries that threaten the limb and demand rapid, orderly care. We report a polytrauma patient with a closed posterior hip dislocation, an ipsilateral open knee dislocation with neurovascular compromise, and a left floating hemipelvis defined by fractures of the superior and inferior pubic rami with sacroiliac joint disruption. This constellation creates a floating hip and makes standard hip reduction unsafe because axial traction through the knee can aggravate soft tissue and vascular injury. We used a modified Allis maneuver that redirects traction to the femur while the knee is rigidly immobilized and the pelvis is stabilized. Closed reduction was achieved promptly. Given persistent ischemia and a Mangled Extremity Severity Score (MESS) of 9, urgent guillotine above-knee amputation was performed. This case underscores priorities that should guide similar presentations: immediate hemodynamic stabilization, continuous reassessment of neurovascular status, protection of compromised soft tissues, and early but safe hip reduction that avoids loading an unstable knee.