Knee flexion angle at initial contact during jump landing in individuals with and without chronic ankle instability: A critically-appraised topic

Clinical Scenario: Chronic ankle instability (CAI) is characterized by the residual symptoms and feelings of instability that persist after an acute ankle sprain. Current literature has identified several neuromuscular impairments associated with CAI that may negatively impact sagittal plane knee kinematics during dynamic activities. This has led researchers to begin examining sagittal plane knee kinematics during jump landing tasks. Understanding changes in movement patterns at the knee may assist clinicians in designing rehabilitation plans that target both the ankle and more proximal joints, such as the knee. Clinical Question: What is the evidence to support the notion that patients with CAI have decreased sagittal plane knee flexion angle at initial contact during a jump-landing task compared to healthy individuals? Summary of Key Findings: The literature was systematically searched for level 4 evidence or higher. The search yielded two case-control studies which met the inclusion criteria. Based on limited evidence, there are mixed results for whether sagittal plane knee kinematic at initial contact differ between those with and without CAI. Clinical Bottom Line: There is weak evidence to support changes in sagittal plane knee kinematics at initial contact during a jump landing in individuals with CAI compared to healthy controls. Strength of Recommendation: In accordance with the Centre for Evidence- Based Medicine, a grade of C for level 4 evidence is recommended due to variable findings.