Lachman test evaluated. Quantification of a clinical observation

Area of Science:

• Orthopedics
• Sports Medicine
• Biomechanics

Background:

• The Lachman test is a key clinical assessment for anterior cruciate ligament (ACL) integrity.
• Current Lachman test reporting is limited to a simple positive or negative result.
• A more detailed clinical grading system is needed for positive Lachman test findings.

Purpose of the Study:

• To introduce and validate a novel clinical grading system for positive Lachman test examinations.
• To provide a quantitative framework for assessing ACL laxity beyond a binary outcome.

Main Methods:

• Development of a four-grade clinical scoring system (Grade I-IV) based on observable and active tibial translation.
• Clinical assessment of 75 patients with arthroscopically confirmed complete ACL tears using the new grading system.
• Objective measurement of anterior tibial subluxation in millimeters using arthrometry for all patients.

Main Results:

• The developed clinical grading system effectively categorized different levels of anterior tibial laxity.
• Statistical analysis (ANOVA, Scheffe) confirmed significant differences in mean anterior tibial displacement measurements across the defined laxity groups.
• The grading system demonstrated a strong correlation with objective arthrometric data.

Conclusions:

• The proposed clinical grading system offers a reliable and objective method for evaluating ACL integrity during the Lachman test.
• This system enhances the diagnostic value of the Lachman test by providing graded assessments of knee laxity.
• The findings support the use of this grading system in clinical practice for improved ACL injury assessment.