The relationship between grading and instrumented measurements of anterior knee joint laxity

Context: The relationship between clinical judgments of anterior knee laxity and instrumented measurement of anterior tibial translation is unclear. Objective: To examine the relationship between certified athletic trainers' grading of anterior knee laxity and instrumented measurements of anterior tibial translation. Design: Randomized, blinded, clinical assessment. Setting: Laboratory. Participants: Model patients receiving evaluation of anterior knee laxity. Intervention: Twelve model patients were evaluated using a MEDmetric® KT1000™ knee ligament Arthrometer® to establish instrumented measurements of anterior translation values at the tibio-femoral joint. Twenty-two certified athletic trainers were provided with operational definitions of potential laxity grades and examined the model patients to make judgments of anterior knee laxity. Main Outcome Measures: Correlation between clinical judgments and instrumented measurements of anterior tibial translation. Results: Clinical judgments and instrumented measurements were mutually independent. Conclusions: Anterior tibial translation grading by certified athletic trainers should be interpreted with caution during clinical decision-making.