Cutting edge Orthopedics

Knee Dislocations Mahesh KumarYarlagadda, Frank R. Avilucea, Samuel Neil Crosby Jr, Manish K. Sethi,WilliamT. Obremskey M. K. Yarlagadda (  ) Department of Orthopedic Trauma, Vanderbilt University Medical Center, Meharry Medical College, Nashville, TN, USA e-mail: myarlagadda15@email.mmc.edu F. R. Avilucea Department of Orthopedic Surgery, Division of Orthopedic Trauma, University of Cincinnati Medical Center, Cincinnati, OH, USA S. N. Crosby Jr Elite Sports Medicine and Orthopedic Center, Nashville, TN, USA M. K. Sethi Department of Orthopedic Surgery and Rehabilitation, Vanderbilt University Medical Center, Nashville, TN, USA W. T. Obremskey Department of Orthopedic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA MS: 33-Year-Old Male with Knee Pain Case Presentation MS is a 33-year-old male who presents to the emergency department after sustaining a motorcycle accident in which he slid on a patch of ice and lost control of his motorcycle. Upon presentation to the emergency department, his chief complaint is of right knee and leg pain. On primary survey, he demonstrates a GCS of 15, a patent airway, and is hemodynamically stable. On secondary survey, no gross deformity is noted to his right lower extremity. His past medical history is negative; he takes no medications and has no allergies. On physical examination, there are no open wounds on his thigh, knee, or leg. MS has an effusion of the right knee. Passive range of motion is from 0° to 90° of flexion and is painful. Examination of the right knee demonstrates a positive anterior drawer, a positive posterior drawer, and a positive Lachman sign. The dial test is equivocal secondary to pain. Gross instability is noted to varus and valgus stress at 0 and 30° of flexion. The patient’s dorsalis pedis and posterior tibialis pulses are palpable but decreased compared to the contralateral extremity. Sensation to light touch is intact in all dermatomal distributions and is equal to the contralateral extremity. No pain is elicited with passive stretch of toes. Compartments are firm but compressible. No pain or deformity is noted in the thigh, the ankle, or the foot. Radiographs and MRI of the left knee are demonstrated in Figs. 1a, b and 2a–d.