Classification of knee ligament instabilities. Part II. The lateral compartment

Area of Science:

• Orthopedic surgery
• Sports medicine
• Biomechanics

Background:

• Lateral knee instability is less common but more debilitating than medial instability.
• Diagnostic tests for lateral knee instability are often subtle and prone to misinterpretation.
• Rotatory subluxation is a key component of lateral knee instability.

Purpose of the Study:

• To clarify the diagnostic signs of posterolateral and anterolateral rotatory subluxation.
• To improve the accuracy of diagnosing lateral knee instability.
• To highlight the challenges in clinical assessment of knee instability.

Main Methods:

• Review of diagnostic tests for lateral knee instability.
• Description of clinical findings for specific rotatory subluxations.
• Analysis of the anterior drawer and posterior drawer tests in neutral rotation.

Main Results:

• Posterolateral rotatory subluxation may present as a positive posterior drawer test or external rotation-recurvatum test.
• Anterolateral rotatory subluxation is indicated by tibial prominence in the anterior drawer test.
• Subtle changes in tibial condyle prominence are key diagnostic indicators.

Conclusions:

• Accurate interpretation of specific knee drawer and rotation tests is crucial for diagnosing lateral instability.
• Clinical examination requires careful attention to subtle signs of rotatory subluxation.
• Improved understanding of diagnostic tests can reduce misdiagnosis of disabling knee injuries.