Related Experiment Video
Updated: Sep 1, 2026

Application of Atomic Force Microscopy to Detect Early Osteoarthritis
Published on: May 24, 2020
Extension-induced changes in the microrelief of the human volar forearm: variations with age
P Corcuff1, O de Lacharrière, J L Lévêque
1Laboratoires de Recherche Avancée de L'Oréal, Aulnay-sous-Bois, France.
Abstract:
The skin microrelief can be assessed in vivo using a noninvasive method based on the image analysis of negative replicas, shadowed by oblique illumination. This technique was used to study changes in the surface furrows of the human volar forearm, related to the degree of extension, in volunteers of three age groups. Results confirmed that the skin in elderly subjects can be characterized by the lack of one of the two perpendicular furrow orientations observed in the young. During extension of the arm, the response of the microrelief in young subjects was clearly different from that in the elderly. Young skin buffered strain through a progressive shift in line density and furrow depth from one orientation to the other, whereas in the elderly, a progressive rotation of the single furrow orientation occurred. These differences would appear to be related to changes in the architecture and physical properties of the dermis. Microrelief, in the elderly subjects, showed a mean line density of 24/cm, regardless of the degree of extension. This constancy may reflect the ultimate stage in the chronological aging of the skin and may be characteristic of a loosened and relaxed dermis.
Related Concept Videos
Bones of the Upper Limb: Humerus
Bones of the Upper Limb: Ulna
Bones of the Upper Limb: Radius
The radius has a nail-shaped head, and a short...
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Muscles that Move the Forearm
Forearm Flexors
The biceps brachii, brachialis, and brachioradialis are forearm flexors. The biceps brachii is made up of two heads. Its long head originates at the supraglenoid tubercle of the scapula, whereas that of the short head is...
Muscles of the Forearm that Move the Hand and Fingers
Anterior Compartment
The anterior compartment muscles originate from the humerus. They primarily function as flexors and are also known as flexor muscles. They typically insert on the carpals, metacarpals, and phalanges. The superficial layer includes the flexor carpi radialis,...

