Analyzing Lower Limb Muscle Imbalance Patterns Associated With Chronic Ankle Instability.

Area of Science:

• Physiotherapy and Sports Medicine
• Biomechanics and Motor Control

Background:

• Chronic ankle instability (CAI) is a prevalent condition often associated with impaired neuromuscular control.
• Proximal-distal muscle imbalances in the lower limb may play a significant role in the development and persistence of CAI.

Purpose of the Study:

• To investigate the complex relationship between chronic ankle instability and proximal-distal muscle imbalances.
• To identify specific muscle groups and functional deficits associated with CAI.

Main Methods:

• A cross-sectional study involving 111 volunteers with CAI.
• Assessments included manual muscle testing, range of motion evaluation, and gait pattern analysis.

Main Results:

• Individuals with CAI demonstrated significant muscle imbalances, with 87.2% exhibiting core muscle weakness (multifidus, rectus abdominis) and 84.6% showing lower limb muscle weakness.
• Ankle joint range of motion was notably affected, particularly plantar flexors and evertors.
• Abnormal gait patterns were observed, including cautious gait (75%), knee hyperextension (22%), and foot slap (3%).

Conclusions:

• CAI can lead to abnormal gait due to muscle weakness, impaired length-tension relationships, and reduced range of motion.
• Core muscle strength is crucial for kinetic chain efficiency and proximal stability, directly impacting CAI.
• Addressing lower limb muscle imbalance and core weakness is vital for effective CAI rehabilitation and improved functional outcomes.