Ultra-Low-Velocity Knee Dislocations

Background: Reports of low-velocity knee dislocations have focused primarily on dislocations occurring during athletic competition. The authors identified a subset of patients with low-velocity knee dislocations that occurred during activities of daily living, such as stepping off a curb, stepping off a stair, or simply falling while walking (ultra-low-velocity dislocations).Hypothesis: Ultra-low-velocity knee dislocations are common in obese individuals and are associated with more complications than high-velocity knee dislocations.Study Design: Case series; Level of evidence, 4.Methods: A review of records identified 17 patients with knee dislocations that occurred during daily activities. All 17 were clinically obese, with an average body mass index (BMI) of 48 (BMI <25 is normal; ≥40 is severe obesity). Ligament injuries occurred in all 17 patients, neurologic injuries in 7, and popliteal artery injuries in 7. Thirteen (76.4%) of the 17 dislocations were anterior, 2 (11.8%) were posterior, and 2 (11.8...