Landmarks, medical and surgical / by Luther Holden.

  • Luther Holden
Date:
1877
Catalogue details

Licence: Public Domain Mark

Credit: Landmarks, medical and surgical / by Luther Holden. Source: Wellcome Collection.

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    point of perineum. 40 LANDMARKS MEDICAL AND SURGICAL. Raphe. '^'^, A slight central ridge of skin, called the raphe, runs from the anus up the perineum, scrotum, and penis. This ' raphe,' or middle line of the perineum, is the ' line of safety ' in making incisions to let out matter or effused urine, or to divide a stricture. Central^ 89. It is very important to know that a point of the raphe about midway between the scrotum (where it joins the perineum) and the centre of the anus, corresponds with the so-called ' central tendon ' where the perineal muscles meet. The bulb of the urethra lies above this point, and nevei, at any age, comes lower down. The artery of the bulb, too, never runs below this level. Therefore the in- cision in lithotomy should never commence above it. A knife introduced at this point, and pushed backwards with a very slight inclination upwards, would enter the mem- branous part of the urethra just in front of the prostate gland ; pushed still farther it would enter the neck of the bladder. This point, then, is a very good landmark to the urethra in lithotomy, or, indeed, to any operations on the perineum. The incision in the lateral operation for lithotomy, be- ginning below the point indicated, should be carried down- wards and outwards between the anus and the ischium, a little nearer to the ischium than the anus. Triangular 90. In a thin perineum, we can feel the lower border igamen . ^^ ^-^^ deep perineal fascia or the so-called triangular liga- ment of the urethra. The urethra passes through it about one inch below the lower part of the symphysis pubis, and about three-quarters of an inch higher than the central tendon of the perineum. It is important to bear in mind these landmarks in introducing a catheter. If the catheter be depressed too soon, its passage will be resisted by the triangular ligament; if too late, it will be likely to make a false passage by running through the bulb. Anus. 91. One of the most important landmarks which guide a surgeon in his operations about the anus, is a white line which was first pointed out by Mr. Hilton,^ and can be ^ ' Lectures on Rest and Pain,' p. 280.