Pelvis and Perineum

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32 Topographic Anatomy

STUDYAIMS

At the end of your study, you should be able to:

Know the functions of the bonypelvis and pelvic girdle

Identifyprominent landmarks and their clinical relevance

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GUIDE

Pelvis and Perineum: Topographic Anatomy

[Plate 331, Pelvis and Perineum]

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[Plate 334, Sex Differences of Pelvis: Measurements]

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[Plate 377, Pelvic Scans: Sagittal MRImages]

Functions of the Pelvic Girdle

Site of attachment of axial skeleton and lower limbs

Transmits weight of upper limbs, head, neck and trunk to lower limb

Involved in balance

Protects and contains pelvic viscera (distal ureters, bladder, rectum, sigmoid colon, reproductive organs)

Key Landmarks

Anterior superior iliac spine (ASIS)

Site of lateral attachment of inguinal ligament

Site of attachment of sartorius and tensor fascia lata muscles Pubic tubercle

Medial point of attachment of inguinal ligament Pubic symphysis

Secondarycartilaginous joint

Location of T12 dermatome along its superior margin

Midpoint between pubic tubercle andASIS marks the site for palpating the femoral arteryand vein (the midinguinal point) Iliac crest

Follows a curve between the anterior and posterior superior iliac spines

Highest point is at approximatelythe level of the umbilicus-level of L4 vertebral body

Supracristal plane passes between the highest points of the iliac crests Intergluteal or natal cleft

The cleft between the buttocks

Site of pilonidal sinus and abscess formation

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