Ankle instability: evaluation of the lateral ligaments

Area of Science:

• Orthopedics
• Sports Medicine
• Biomechanics

Background:

• Ankle injuries are common, particularly among athletes.
• Accurate assessment of ankle ligamentous integrity is crucial for diagnosis and treatment.
• Standardized stress testing protocols are needed for reliable evaluation.

Purpose of the Study:

• To assess the reproducibility of bilateral ankle stress testing in healthy subjects.
• To compare the effectiveness of inversion (talar tilt) and anterior drawer tests in evaluating lateral ankle ligamentous integrity.

Main Methods:

• Bilateral ankle stress testing was performed on 25 asymptomatic subjects using a device for controlled foot positioning and force application.
• Inversion and anterior drawer tests were conducted in neutral and plantarflexed positions.
• Reproducibility was assessed, and the influence of prior injury, handedness, and anthropometrics was evaluated.

Main Results:

• The ankle stress tests demonstrated high reproducibility.
• No significant differences were found based on previous injury history, handedness, or anthropometric measurements.
• In normal ankles, talar tilt ranged from 0-18 degrees, and anterior displacement was up to 3 mm.
• The effective stiffness of the anterior talofibular ligament was calculated as 65 +/- 34 N/m.

Conclusions:

• Anterior drawer testing appears to be a more critical evaluation of lateral ligamentous integrity than the talar tilt test.
• Standardized ankle stress testing is reproducible and reliable in asymptomatic individuals.
• These findings support the use of anterior drawer testing for assessing lateral ankle stability.