Effects of Age on Strength and Morphology of Toe Flexor Muscles

• Published in: The journal of orthopaedic and sports physical therapy 2016-12, Vol.46 (12), p.1065-1070
• Main Authors: Mickle, Karen J, Angin, Salih, Crofts, Gillian, Nester, Christopher J
• Format: Article
• Language: English
• Subjects: Adult; Age Factors; Aged; Cross-Sectional Studies; Female; Humans; Male; Muscle Strength - physiology; Muscle, Skeletal - physiology; Toe Joint - physiology; Toes - physiology; Young Adult
• ISSN: 0190-6011; 1938-1344
• DOI: 10.2519/jospt.2016.6597

Study Design Descriptive, cross-sectional. Background Age-related muscle atrophy is common in lower-limb muscles. We therefore speculated that foot muscles may also diminish with age. However, there is a paucity of literature characterizing foot muscle strength and morphology, and any relationship between these 2, in older people. Objective To compare the strength and size of the toe flexor muscles of older adults relative to their younger counterparts. Methods Seventeen young adults with a normal foot type were matched by sex and body mass index to 17 older adults with a normal foot type, from an available sample of 41 younger (18 to 50 years of age) and 44 older (60 or more years of age) adults. Among the matched groups (n = 34), muscle thickness and cross-sectional area for 5 intrinsic and 2 extrinsic toe flexor muscles were obtained using ultrasound. Toe strength was assessed using a pressure platform. Differences in toe flexor strength and muscle size between the young and older matched groups were determined using analysis of covariance (controlling for height). Correlations between strength and size of the toe flexor muscles of the pooled group (n = 34) were also calculated. Results Toe strength and the thickness and cross-sectional area of most foot muscles were significantly reduced in the older adults (P