Site-specific differences in the association between plantar tactile perception and mobility function in older adults

Area of Science:

• Gerontology
• Neuroscience
• Biomechanics

Background:

• Impaired somatosensation is common in older adults, contributing to mobility loss.
• Understanding somatosensory function at specific foot sites is crucial for targeted interventions and clinical assessments.

Purpose of the Study:

• To investigate the differential relationship between tactile perception at various plantar foot sites and mobility function in older adults.
• To identify specific foot regions where somatosensory impairment most significantly impacts balance and walking.

Main Methods:

• Tactile perception was assessed using a 10 g monofilament at four plantar foot sites: great toe (GT), first metatarsal head (MT1), heel (H), and fifth metatarsal head (MT5).
• Mobility function was evaluated using the Berg Balance Scale and measures of usual and maximal walking speed.

Main Results:

• Tactile perception at all tested sites was positively associated with the Berg Balance Score.
• Tactile perception at the MT1 site showed the strongest association with both Berg Balance Score and walking speeds (usual and maximal).
• Mild somatosensory impairment specifically at the MT1 site correlated with significant deficits in balance and walking.

Conclusions:

• Tactile perception at the MT1 site is more strongly associated with mobility function in older adults than at other plantar foot locations.
• Future interventions and clinical assessments focusing on the MT1 site may offer enhanced benefits for improving mobility in older populations.