Skin tension or skin compression? Small circular wounds are likely to shrink, not gape
Renovo Group plc, The Manchester Incubator Building, 48 Grafton Street, Manchester M13 9XX, UK.Journal of Plastic Reconstructive & Aesthetic Surgery (Impact Factor: 1.42). 05/2008; 61(5):529-34. DOI: 10.1016/j.bjps.2007.06.004
The final appearance of a scar may be influenced by tension or mechanical factors [Borges AF. Scar prognosis of wounds. Br J Plast Surg 1960; 13:47-54; Arem AJ, Madden JW. Effects of stress on heating wounds. J Surg Res 1976;20:93-102; Burgess LP, Morin GV, Rand M, et at. Wound heating. Relationship of wound closing tension to scar width in rats. Arch Otolaryngol Head Neck Surg 1990; 116:798-802; Meyer M, McGrouther DA. A study relating wound tension to scar morphology in the pre-sternal scar using Langer's technique. Br J Plast Surg 1991;44:291-4] Karl Langer suggested that information could be gained about the tension inherent in skin, in all directions, by observing the wound edge retraction that occurred after making circular skin incisions [Langer K. On the anatomy and physiology of the skin II. Skin tension. Br J Plast Surg 1978;31:93-106]. Circular wounds may be used to demonstrate the orientation of the dominant axis of 'tension' in the skin but is this always a tensile stress as opposed to a compressive stress? This is the second article in a series documenting the mechanical properties of circular punch biopsy wounds. The aim of this study was to make detailed observations of the dimensional distortions of circular wounds on the face and neck, from which deductions could be made with regard to mechanical stress. One hundred and seventy-five benign head and neck lesions were excised from 72 volunteers using circular dermal punch biopsies. The distortions of the resulting wounds were observed to be elliptical in most cases. Measurements were taken of the maximum and minimum diameters of the wound and expressed as ratios of the size of the punch biopsy used for excision. The change in area from the area of the punch biopsy to that of the wound was also calculated.
[Show abstract] [Hide abstract]
- "However, the underlying mechanism, which is thought to be contributed by the hydrated PG-rich matrix in the dermis, is not clearly understood (Hukins 1983; Silver et al. 2003). The anisotropy of skin addresses the orientation of the collagen fibres, as well as elastic fibres (Bush et al. 2008), and the proportion of these fibres that could be recruited into tension for resisting the load that tends to rupture the tissue. The orientation of these fibres is thought to be related to the clinically observed Langer's lines—which are identified with the direction of maximum tension (Ridge and Wright 1965). "
ABSTRACT: The mechanical response of skin to external loads is influenced by anisotropy and viscoelasticity of the tissue, but the underlying mechanisms remain unclear. Here, we report a study of the main effects of tissue orientation (TO, which is linked to anisotropy) and strain rate (SR, a measure of viscoelasticity), as well as the interaction effects between the two factors, on the tensile properties of skin from a porcine model. Tensile testing to rupture of porcine skin tissue was conducted to evaluate the sensitivity of the tissue modulus of elasticity (E) and fracture-related properties, namely maximum stress [Formula: see text] and strain [Formula: see text] at [Formula: see text], to varying SR and TO. Specimens were excised from the abdominal skin in two orientations, namely parallel (P) and right angle (R) to the torso midline. Each TO was investigated at three SR levels, namely 0.007-0.015 [Formula: see text] (low), 0.040 [Formula: see text] (mid) and 0.065 [Formula: see text] (high). Two-factor analysis of variance revealed that the respective parameters responded differently to varying SR and TO. Significant changes in the [Formula: see text] were observed with different TOs but not with SR. The [Formula: see text] decreased significantly with increasing SR, but no significant variation was observed for different TOs. Significant changes in E were observed with different TOs; E increased significantly with increasing SR. More importantly, the respective mechanical parameters were not significantly influenced by interactions between SR and TO. These findings suggest that the trends associated with the changes in the skin mechanical properties may be attributed partly to differences in the anisotropy and viscoelasticity but not through any interaction between viscoelasticity and anisotropy.Biomechanics and Modeling in Mechanobiology 07/2015; DOI:10.1007/s10237-015-0700-2 · 3.15 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: A computational algorithm to study the evolution of complex wound morphologies is developed based on a model of wound closure by cell mitosis and migration due to Adam [Math Comput Model 30(5-6):23-32, 1999]. A detailed analysis of the model provides estimated values for the incubation and healing times. Furthermore, a set of inequalities are defined which demarcate conditions of complete, partial and non-healing. Numerical results show a significant delay in the healing progress whenever diffusion of the epidermic growth factor responsible for cell mitosis is slower than cell migration. Results for general wound morphologies show that healing is always initiated at regions with high curvatures and that the evolution of the wound is very sensitive to physiological parameters.Journal of Mathematical Biology 11/2009; 59(5):605-30. DOI:10.1007/s00285-008-0242-7 · 1.85 Impact Factor
- Journal of Plastic Reconstructive & Aesthetic Surgery 03/2009; 62(5):705-6. DOI:10.1016/j.bjps.2008.12.025 · 1.42 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.