Pathologic investigation of cutaneous stretch

Unevenly stretched skin of the back of rats resulted in microscopic as well as light microscopic features of wounding with subsequent repair as a result of the trauma due to this type of stretch. In skin evenly stretched, dermal collagen was markedly thickened and homogeneous as compared to controls. The increased thickness of evenly stretched skin despite its increase in surface area is consonant with views indicating that stretch may increase the synthesis of diminish the degradation of dermal collagen. The validity of this conclusion, however, is dependent upon the premise that the evenly stretched skin is also "wounded" since this latter would be required to account for the rapid turnover of collagen in these rather acute experiments. This implies a defect at a molecular or biochemical level since no qualitative structural alterations were detected by the conventional techniques employed.