08-04-2011, 11:56 AM
The correct answer is D. Did the patient or someone
else hear a pop? If yes, suspect ACL tear (80%), meniscal
injury (15%), and rarely a fracture. When did you
notice swelling? If 0–12 hours after the injury, suspect
ACL tear or patellar dislocation/subluxation; if 12–24
hours, suspect meniscal injury. If there is hemarthrosis
on aspiration, suspect ACL injury (greater than 75%), patellar subluxation,
or intraarticular fracture. A history of “My
knee gives way; buckles; feels loose; or comes apart”
may be secondary to patellar subluxation/dislocation,
ACL deficiency, or arthritis. Collateral ligament injuries,
MCL, or lateral collateral ligament (LCL) do not typically
present with significant effusion and typically feel
stable with forward ambulation but are painful with sideto-
side movements. Muscle or tendon rupture may
cause buckling, but will not typically cause effusion and
will generally have an obvious deformity and inability to
bear weight.
else hear a pop? If yes, suspect ACL tear (80%), meniscal
injury (15%), and rarely a fracture. When did you
notice swelling? If 0–12 hours after the injury, suspect
ACL tear or patellar dislocation/subluxation; if 12–24
hours, suspect meniscal injury. If there is hemarthrosis
on aspiration, suspect ACL injury (greater than 75%), patellar subluxation,
or intraarticular fracture. A history of “My
knee gives way; buckles; feels loose; or comes apart”
may be secondary to patellar subluxation/dislocation,
ACL deficiency, or arthritis. Collateral ligament injuries,
MCL, or lateral collateral ligament (LCL) do not typically
present with significant effusion and typically feel
stable with forward ambulation but are painful with sideto-
side movements. Muscle or tendon rupture may
cause buckling, but will not typically cause effusion and
will generally have an obvious deformity and inability to
bear weight.