Summary
The toes play a critical role in stabilizing the body during weightbearing activities, yet the determinants of toe plantarflexion strength and practical methods for identifying toe weakness are not well established. This study examined age- and sex-related differences in toe plantarflexion strength and evaluated the validity of a simple clinical screening tool—the paper grip test. Plantarflexion strength of the hallux and lesser toes was assessed in 40 young adults (mean age 20.8 years) and 40 older adults (mean age 74.6 years), with equal numbers of men and women, using a pressure platform alongside the paper grip test.
Older participants demonstrated substantially reduced strength, with 32% lower hallux and 27% lower lesser-toe plantarflexion strength compared with younger participants. Women showed 42% lower hallux strength than men, while no sex difference was observed for lesser-toe strength. Participants who failed the paper grip test had significantly weaker plantarflexion strength in both the hallux and lesser toes. The test demonstrated good diagnostic accuracy, with sensitivities and specificities ranging from 74% to 80% for identifying clinically relevant toe weakness.
These findings indicate that toe plantarflexion strength declines with aging and that the paper grip test is a valid, practical screening tool for detecting toe weakness in clinical settings.
PMID: 17207439
DOI: 10.1177/107110070602701217
Abstract
Background
The toes play an important stabilizing role in weightbearing activities. However, the factors that influence toe plantarflexion strength are poorly understood, and there are no validated measures for assessing toe weakness in the clinical setting. Therefore, the objectives of this study were to determine whether plantarflexion strength of the toes differs according to age and gender and to evaluate the validity of a clinical screening test for assessing toe plantarflexor weakness (the paper grip test).
Methods
Plantarflexion strength of the hallux and lesser toes was measured in 40 young participants (20 men and 20 women, mean age 20.8 +/- 2.2 years) and 40 older participants (20 men and 20 women, mean age 74.6 +/- 5.7 years) using a pressure platform in conjunction with clinical assessment using the paper grip test.
Results
Older participants exhibited 32% less plantarflexion strength of the hallux and 27% less plantarflexion strength of the lesser toes compared to younger participants, and women exhibited 42% less hallux plantarflexor strength than men. Gender did not influence lesser toe plantarflexor strength. Participants who failed the paper grip test exhibited significantly reduced plantarflexion strength for both the hallux and lesser toes. The sensitivity and specificity of the paper grip test of the hallux to predict plantarflexor strength less than 2.6 kg was 80% and 79%, respectively, and the sensitivity and specificity of the paper grip test of the lesser toes to predict plantarflexor strength less than 2.2 kg was 75% and 74%, respectively.
Conclusions
These findings indicate that aging is associated with reduced plantarflexion strength of the toes. The paper grip test may be a useful screening tool to detect toe weakness in the clinical setting.
Menz HB, Zammit GV, Munteanu SE, Scott G. Plantarflexion strength of the toes: age and gender differences and evaluation of a clinical screening test. Foot Ankle Int. 2006 Dec;27(12):1103-8. doi: 10.1177/107110070602701217. PMID: 17207439.