The purpose of this study is to present the usefulness of arthrometer (KT-2000) in patients with anterior knee instability and to assist in evaluating an objective prognosis after anterior cruciate ligament reconstruction.

We analyzed the manual maximum anterior displacement, passive anterior displacement at 30Ib force and compliance index between 15Ib and 30Ib, measured by KT-2000 in 82 cases of patient who had unilateral anterior knee instability and 40 cases of volunteers, as control group, who had no history of knee injury. We used the Paired and Independent t-test for statistical analysis.

In control group, the mean value of manual maximum anterior displacement is 0.8 ± 0.9mm, passive anterior displacement, 1.4 ± 1.3mm and compliance index, 1.1 ± 1.1mm. In patient group, the mean value of manual maximum anterior displacement is 7.1 ± 2.7mm, passive displacement, 6.1 ± 2.6mm and compliance index, 3.8 ± 1.8mm. We found that the patient group was revealed much higher degree of anterior displacement than the control group (p<0.005).

KT-2000 is objective and quantitative in diagnosis of anterior knee instability.