History of locking episodes suggests a meniscal tear
A sensation of popping at the time of injury suggests<unk> ous injury, probably complete rupture of a<unk>  (third-degree tear)
Episodes of giving way are consistent with some degree of knee instability and may indicate patellar subluxation or<unk> ous rupture
Rapid onset (within two hours) of a large, tense effusion suggests rupture of the anterior cruciate<unk>  or fracture of the tibial plateau with resultant hemarthrosis, whereas slower onset (24 to 36 hours) of a mild to moderate effusion is consistent with meniscal injury or<unk> ous sprain. Recurrent knee effusion after activity is consistent with meniscal injury.
Hearing/feeling a "pop" during injury with ensuing knee instability is pathognomonic
Lever Sign or Lelli’s test (highest sensitivity at 94-100%). Demonstrated to be effective and 100% sensitive in a small ED study, especially compared to traditional methods.
Place a fist under the proximal third of the calf, opposite from tibial tuberosity
Apply moderate force to the anterior quadriceps
Heel should raise off table if there is not a complete rupture of ACL
Place a fist under the proximal third of the calf, opposite from tibial tuberosity
Apply moderate force to the anterior quadriceps
Heel should raise off table if there is not a complete rupture of ACL
Anterior Drawer Sign
Pt supine, knee flexed 90', attempt to displace tibia from femur in a forward direction
Displacement of >6mm compared w/ opposite knee indicates injury
Lachman Test
Pt supine, knee flexed 30', femur held w/ one hand, prox tibia pulled up w/ other hand
Displacement >5mm or soft end-point indicates injury
Pivot Shift Test
Segond Fracture
Pathognomonic for ACL tear but rare
Pt supine, knee flexed 90', attempt to displace tibia from femur in a forward direction
Displacement of >6mm compared w/ opposite knee indicates injury
Pt supine, knee flexed 30', femur held w/ one hand, prox tibia pulled up w/ other hand
Displacement >5mm or soft end-point indicates injury
Pathognomonic for ACL tear but rare
Posterior Drawer Sign
Patient supine, knee flexed 90', attempt to displace tibia from femur in backward direction
Patient supine, knee flexed 90', attempt to displace tibia from femur in backward direction
Symptoms
"Locking" of joint or sensation of popping, clicking, or snapping
Signs
Effusions that occur after activity
Joint-line tenderness
Tests
McMurray, grind test only 50% Sn
"Locking" of joint or sensation of popping, clicking, or snapping
Effusions that occur after activity
Joint-line tenderness
McMurray, grind test only 50% Sn
Meniscus and ligament knee injuries
Knee dislocation
Acute knee injury
Knee fractures
Ankle syndesmosis injury
Patella fracture
Boxer's fracture
Segond fracture