Methods to diagnose acute anterior cruciate ligament rupture: a meta-analysis of instrumented knee laxity tests.

PURPOSE

The aims of this meta-analysis were to determine the sensitivity and specificity of the KT 1000 Arthrometer, Stryker Knee Laxity Tester and Genucom Knee Analysis System for ACL rupture. It was hypothesized that the KT 1000 test is the most sensitive and specific. Secondly, it was hypothesized that the sensitivity and specificity of the KT 1000 arthrometer increase when the amount of Newton force is increased.

METHODS

An electronic database search was performed using MEDLINE and EMBASE. All cross-sectional and cohort studies comparing one or more instrumented examination tests for diagnosing acute complete ACL rupture in living human subjects to an accepted reference standard such as arthroscopy, arthrotomy and MRI were included.

RESULTS

The sensitivity of the KT 1000 Arthrometer with 69 N was 0.54. With 89 N, the sensitivity was 0.78 and the specificity 0.92, and with maximum manual force, the sensitivity was 0.93 and the specificity 0.93. For the Stryker Knee Laxity Tester, the sensitivity was 0.82 and the specificity 0.90. And for the Genucom Knee Analysis System, the sensitivity was 0.74 and the specificity 0.82.

CONCLUSION

The KT Arthrometer performed with maximum manual force has the highest sensitivity, specificity, accuracy and positive predictive value for diagnosing ACL rupture.

LEVEL OF EVIDENCE

Meta-analysis, level I.