Ankle strength impairments associated with knee osteoarthritis

Area of Science:

• Biomechanics
• Orthopedics
• Musculoskeletal Health

Background:

• Knee osteoarthritis (KOA) is associated with altered ankle biomechanics.
• The specific impact of KOA on ankle muscle strength remains unclear.
• This study investigates ankle plantar flexor and dorsiflexor strength in KOA patients across severity levels.

Purpose of the Study:

• To evaluate ankle muscle strength in patients with knee osteoarthritis.
• To compare plantar flexor and dorsiflexor torque across different degrees of knee osteoarthritis severity.
• To explore potential compensatory mechanisms in ankle muscles related to knee osteoarthritis.

Main Methods:

• 37 knee osteoarthritis patients and 15 controls underwent clinical and radiographic assessment.
• Participants were categorized into control, mild KOA, and moderate KOA groups.
• Ankle muscle torque was measured using a Biodex dynamometer in isometric, concentric, and eccentric modes.

Main Results:

• Mild KOA patients exhibited significantly lower concentric plantar flexion peak torque than controls.
• No significant differences in concentric plantar flexion torque were observed between moderate KOA and control groups.
• The ratio of plantar flexion to dorsiflexion torque was significantly lower in mild KOA compared to controls and moderate KOA.

Conclusions:

• Ankle plantar flexion strength is impaired in knee osteoarthritis patients, especially in mild stages.
• Moderate knee osteoarthritis may involve compensatory strategies in plantar flexor muscles.
• Ankle muscle torque assessment can provide insights into functional deficits associated with knee osteoarthritis.