2 SURGICAL APPLIED ANATOMY. [Chap. i. 



adhesion, it follows that the skin moves in all move- 

 ments of that muscle. The subcutaneous tissue is, like 

 a similar tissue in the palm, admirably constructed to 

 resist pressure, being composed of a multitude of fibrous 

 bands enclosing fat lobules in more or less isolated 

 spaces. The density of the scalp is such, that in 

 surface inflammations, such as cutaneous erysipelas, it 

 is unable to present (except in a very slight degree) 

 two conspicuous features of such inflammations, viz., 

 redness and swelling. The skin is provided with a 

 great number of sebaceous glands, which may develop 

 into cystic tumours or wens, such cysts being more 

 common upon the scalp than in any other 'part of the 

 body. Being skin growths, these cysts, even when 

 large, remain, except in rare instances, entirely out- 

 side the aponeurosis, and can therefore be removed 

 without risk of opening up the area of loose con- 

 nective tissue between the aponeurosis and the peri- 

 cranium. 



There being no fatty tissue in any of the layers 

 that cover the bony vault, save in the subcutaneous 

 layer, it happens that in cases of obesity the scalp 

 undergoes but little change, the fat in the subcu- 

 taneous tissue being limited by the dense fibrous 

 structures that enclose it. The attachment of the 

 hairs collectively to the scalp is so strong that there 

 are many cases, since the days of Absalom, where 

 the entire weight of the body has been supported by 

 the hair of the scalp. Agnew reports the case of a 

 woman whose hair became entangled in the revolving 

 shaft of a machine. The hair did not give way, but 

 the entire scalp was torn off from the skull. The 

 patient recovered. 



The dangerous area of the scalp. Between 

 the aponeurosis and the pericranium is an extensive 

 layer of loose connective tissue, that may, for reasons 

 to be presently given, be fairly called the dangerous 



