Balance dysfunction in hereditary and spontaneous spastic paraparesis

Area of Science:

• Neurology
• Biomechanics
• Human Movement Science

Background:

• Spastic paraparesis (pwSP) is a neurological condition affecting motor function.
• Postural sway, the body's ability to maintain balance, is often impaired in neurological disorders.

Purpose of the Study:

• To investigate postural sway in people with spastic paraparesis (pwSP).
• To determine the influence of specific impairments, such as muscle weakness and stiffness, on postural sway in pwSP.

Main Methods:

• Standing postural sway was measured in 20 pwSP and 18 healthy controls with eyes open and closed.
• Vibration threshold, isometric ankle and hip muscle strength, and ankle stiffness were assessed.

Main Results:

• People with spastic paraparesis exhibited significantly higher antero-posterior (AP) and medio-lateral (ML) sway.
• Reduced muscle strength and increased ankle stiffness were observed in pwSP.
• Hip abductor weakness correlated with increased ML and AP sway, while higher ankle stiffness was associated with reduced AP sway.

Conclusions:

• Postural sway in pwSP is associated with hip abductor muscle weakness, particularly in the ML direction and with reduced sensory input.
• Increased ankle stiffness may contribute to improved AP sway stability, potentially acting as a compensatory mechanism.