Ambrose S, Keighley M R
Ann R Coll Surg Engl. 1985 Sep;67(5):306-8.
One hundred and fifty-eight consecutive patients attending a rectal clinic have undergone measurement of perineal descent at rest and during straining by a simple noninvasive method. In nine patients (5.7%) the perineum was assessed as being below the ischial tuberosities at rest, whilst a further nine patients (5.7%) had abnormal descent (greater than 2.5 cm) during straining. Sixteen of the 18 patients with abnormal descent at rest or on straining were female and in ten (56%) a diagnosis of haemorrhoids was made at the initial clinic attendance. Parity of four or more was associated with a greater degree of descent during straining (P less than 0.05) than in women having a single pregnancy only.
158名连续到直肠科就诊的患者通过一种简单的非侵入性方法测量了静息时和用力排便时的会阴下降情况。9名患者（5.7%）静息时会阴被评估为低于坐骨结节，另有9名患者（5.7%）在用力排便时会阴下降异常（大于2.5厘米）。静息时或用力排便时会阴下降异常的18名患者中有16名是女性，其中10名（56%）在初次就诊时被诊断为痔疮。产次为四次或更多次的女性在用力排便时会阴下降程度比仅怀孕一次的女性更大（P<0.05）。
