LAUS 204 2024 Notes PDF

BSMS MODULE 203: REPRODUCTION AND ENDOCRINOLOGY THEME 2: REPRODUCTIVE SYSTEM, FETAL DEVELOPMENT, PREGNANCY AND BIRTH (THE LIFE CYCLE) - LIVING ANATOMY AND ULTRASOUND OF THE PELVIS Table of Contents Task 1. Surface Landmarks of the Pelvis and Lower Abdomen................................................

BSMS MODULE 203: REPRODUCTION AND ENDOCRINOLOGY THEME 2: REPRODUCTIVE SYSTEM, FETAL DEVELOPMENT, PREGNANCY AND BIRTH (THE LIFE CYCLE) - LIVING ANATOMY AND ULTRASOUND OF THE PELVIS Table of Contents Task 1. Surface Landmarks of the Pelvis and Lower Abdomen................................................... 2 Task 2. Ultrasound Imaging of the Pelvis................................................................................... 7 Ultrasound of the male pelvis................................................................................................... 8 Ultrasound of the female pelvis.............................................................................................. 10 Checklist................................................................................................................................ 12 Learning Outcomes - By the end of the session, you should be able to: Describe and draw the surface marking projections of bones of the pelvis Describe and draw the orientation of organs within the pelvis Describe the anatomy of the pelvis as viewed through ultrasound o Displaying an understanding of the different structures which can be seen in biologically male, female and intersex individuals Apply an understanding of the arrangement of pelvic viscera to clinical scenarios Student Worksheet As with the previous living anatomy session that you have participated in, you will be working in small teams. This session is divided into 2 tasks and will involve locating the surface markings on the pelvis, requiring some palpation of yourself and fellow students. It is hoped that all students will be prepared to palpate and be palpated; however, students who have a reason for not wishing to participate in these activities need only make this clear to their colleagues and staff members in the session. Please be aware that due to the nature of the area being studied in these sessions, we ask that you be respectful and mindful of each other, your conduct and the terminology used. Please also note that any use of the terms male and female in this session refer to biological sex, and not gender identity. Individuals may identify differently to their biological sex assigned at birth, and there are also many variations of the biology and structure of the genital systems which should be considered. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 1 Task 1. Surface Landmarks of the Pelvis and Lower Abdomen Materials to be used in this session. Alcohol gel for preparing hands prior to palpation. Coloured pens for drawing surface markings. Before you begin your examination prepare your hands using the alcohol gel. The left and right hip bones are parts of the bony pelvis. Each hip bone is comprised of the ilium, ischium and pubis. At puberty, these bones fuse together to form one large, irregular bone on both sides. They form part of the pelvic girdle – the bony structure that attaches the axial skeleton to the lower limbs. Name the three main articulations of the hip bone. Figure 04-01A&B. Surface projections of the osteology of the pelvis. A, Anterior female. B, Anterior male. ASIS, anterior superior iliac spine; EO, external oblique; GF, gluteal fold; IC, iliac crest; IgC, intergluteal cleft; IL, inguinal ligament; IT, ischial tuberosity; PSIS, posterior superior iliac spine; PTu, pubic tubercle; ReA, rectus abdominus; Sa, sacrum; Um, umbilicus. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 2 Figure 04-01C&D. Surface projections of the osteology of the pelvis. C, Posterior female. D, Posterior male. ASIS, anterior superior iliac spine; EO, external oblique; GF, gluteal fold; IC, iliac crest; IgC, intergluteal cleft; IL, inguinal ligament; IT, ischial tuberosity; PSIS, posterior superior iliac spine; PTu, pubic tubercle; ReA, rectus abdominus; Sa, sacrum; Um, umbilicus. The ilium is the superior part of the hip bone and consists of the body and wing (ala). The following anatomical landmarks of the ilium are palpable. Anterior superior iliac spine – this is a bony projection situated at the anterior end of the iliac crest and can be felt at the upper lateral end of the groin. In the midline, follow the linea alba inferiorly. Locate and gently palpate the pubic tubercles. Moving laterally, palpate the bony prominence of the ilium at the anterior superior iliac spine. It serves as a point of attachment for the inguinal ligament. It is usually visible in a supine person and may be visible in a thin person when standing. Iliac crest – the superior margin of the wing of the ilium is thickened to form the iliac crest. This can be felt along its entire length and extends from the anterior superior iliac spine (ASIS) to the posterior superior iliac spine (PSIS). A line uniting the highest point on the iliac crest on each side marks the supracristal plane, which corresponds to the level of the 4th lumbar vertebra. Tubercle of the iliac crest – the widest part of the iliac crest is referred to as the tubercle of the ilium. This can be palpated at approximately 5cm posterior to the ASIS. Run fingers posteriorly along the outer surface of the crest from the ASIS until a laterally projecting prominence is found. A line uniting the tubercles on each side marks the transtubercular plane, which corresponds to the level of the 5 th lumbar vertebra. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 3 Anterior inferior iliac spine – this can be palpated at approximately 3cm inferior to the ASIS. It serves as an attachment to the rectus femoris muscle and the proximal part of the iliofemoral ligament. Posterior superior iliac spine - this is a bony projection situated at the posterior end of the iliac crest, in the supero-medial buttock parallel to the midline. It lies at the level of the second sacral vertebra under a small skin depression, which is accentuated when the buttock is clenched. Note: You don’t have to palpate this during this session. The pubis is the anterior and inferior part of the hip bone and has a body and superior and inferior rami. The following anatomical landmarks of the pubis are palpable. Pubic crest – is a bony ridge separating the anterior and posterior surfaces of the pubic bone. It extends laterally as the pubic tubercle and gives attachment to the rectus abdominis, conjoint tendon and the external oblique aponeurosis. It can be palpated by pressing firmly on the lower abdominal wall. Place your fingers on the umbilicus and move downwards until you feel a bony ridge. Pubic tubercle – is found at the lateral end of the crest and serves as an attachment for the inguinal ligament. In the midline, follow the linea alba inferiorly. Locate and gently palpate the pubic tubercles. The ischium is posterior and inferior part of the hip bone. It possesses an ischial spine and an ischial tuberosity. Ischial tuberosity – the posteroinferior aspect of the ischium forms the ischial tuberosities. It gives attachment to the hamstring muscles and sacrotuberous ligament. The weight of our body is taken on the ischial tuberosities when sitting. It is palpable beneath the fold of the buttock, vertically inferior to the skin depression over the posterior superior iliac spine. Flexing the thigh at the hip makes the tuberosity more accessible. Sit on a chair and place your hands on the seat with the palms facing up. Move so that you are sitting on your own hands and palpate the ischial tuberosities. Now compare the orientation of the pelvis in standing and sitting by placing fingertips on the anterior superior iliac spine with one hand and the pubic tubercle with the other. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 4 Internal palpation (for information only) Some of the anatomical landmarks can be palpated internally. The deep surface of the body of the pubis, the pubic symphysis, the ischiopubic ramus and the ischial spines can be palpated on vaginal examination. Palpation of the ischial spines is important for administration of a pudendal block during childbirth. Pudendal nerve block (for information only) There are two main sites of pudendal nerve block. In the transvaginal procedure, the bony landmark is the ischial spine. The ischial spines can be palpated at about a finger-length into the vagina, at 4 and 8 o'clock position. They are felt as bony prominences. The needle of the syringe is passed through the vaginal mucous membrane towards the ischial spine. After the needle passes through the sacrospinous ligament (this is the site where the pudendal nerve passes lateral to the ligament and lies medial to the pudendal vessels), the anaesthetic solution is injected around the nerve. In the perineal procedure, the bony landmark is the ischial tuberosity. The tuberosity is palpated through the buttock and the needle is inserted transcutaneously along the medial side of the tuberosity. The anaesthetic solution is then infiltrated around the nerve. Care should be taken not to administer the anaesthetic into the systemic circulation. What structures accompany the pudendal nerve? Use a skeleton and/or the figures below for the following tasks – The bony edge defining the pelvic inlet is known as the pelvic brim. Name and identify the structures that form the pelvic brim. The bony edge defining the pelvic outlet is known as the inferior pelvic aperture. Name and identify the structures that form the inferior pelvic aperture. Identify the greater and lesser sciatic foramen, and obturator foramen. What structures pass through these foramina? Finally, discuss the differences between the pelvis of a biological male and biological female. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 5 Pelvic inlet Pelvic outlet 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 6 Task 2. Ultrasound Imaging of the Pelvis Materials to be used in session Alcohol gel for preparing hands prior to palpation Ultrasound probe and gel iPad Ultrasound technique It is best to hold the transducer close to its base using one hand, much like you would hold a pen. The marker on the transducer should point either cephalic (towards the head) or to your (the one scanning) left-hand side. In this session, we will use ultrasound to examine the organs which reside within the pelvis. Ensure that the “Bladder” pre-set is selected within the Butterfly application to give you the best starting point for your image. For the best view of the structures within the pelvis, your volunteer being scanned should be laying supine, to prevent abdominal structures obscuring pelvic structures. To find the starting point for your ultrasound probe, which will be the same regardless of male or female anatomy, we advise you ask your volunteer to expose their lower abdomen and indicate the level of superior border of their pubic symphysis (you will not be required to remove clothing for any portion of this session). Superior to this level is where you will be scanning, and ensure you are checking that your volunteer is comfortable with the area being scanned. You should not need to apply much pressure on the probe to be able to visualise the structures, but this will differ from person to person. Considering this, please be mindful of individual comfort levels, and perhaps ask your volunteer to scan themselves in the first instance to assess the pressure needed and if this causes discomfort. Doppler ultrasound can be used effectively in this area to help identify and differentiate blood vessels from other structures, try this during the session as you may find it helpful. Before beginning the ultrasound assessment of your volunteers, think about the potential clinical reasons there could be for performing such an assessment on an individual. - Think about what structures can be seen How well the area is visualised Why this imaging modality would be used 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 7 Ultrasound of the male pelvis Refer to pages 59 to 61 in Gray’s Surface Anatomy and Ultrasound. Identify the following structures: - Bladder Ejaculatory Duct - Prostate - Ductus/Vas Deferens - Seminal Vesicles - Rectum Figure 04-15. Ultrasound of the male pelvis. A, Midsagittal. B, Transverse with the transducer tilted inferiorly. C, Transverse to the right of the midline. †, ejaculatory duct; DD, ductus deferens; EO, external oblique; InC, inguinal canal; ReA, rectus abdominus; *, urethra; EIA, external iliac artery; IC, iliac crest; Pro, prostate; SC, spermatic cord; Bl, bladder; EIV, external iliac vein; Ili, iliacus; Re, rectum; SV, seminal vesicle. Scale bar = 3 cm. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 8 Why is it advised that patients drink 500ml of water the hour prior to undergoing ultrasound examination? What symptoms might a biologically male patient have which would prompt them undergoing a pelvic ultrasound? Which structures join to form the ejaculatory duct (seen in Figure 04-15A on the previous page)? Notes 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 9 Ultrasound of the female pelvis Refer to pages 60 to 63 in Gray’s Surface Anatomy and Ultrasound. Identify the following structures: - Bladder Cervix Ileum - Uterus - Ovary - Rectum - Vagina - Uterine tube Figure 04-16. Ultrasound of the female pelvis. A, Midsagittal. B, Transverse to the right of the midline. C, Transverse with the transducer tilted inferiorly. †, broad ligament; AM, anal mucosa; ExS, external sphincter; InS, internal sphincter; Re, rectum; UT, uterine tubes; VV, vaginal vault. *, endometrium; Bl, bladder; Fu, fundus; IRF, ischiorectal fossa; ReA, rectus abdominus; Ut, uterus; ‡, myometrium; Ce, cervix; Ile, ileum; LeA, levator ani; ROv, right ovary; Va, vagina; Scale bar = 3 cm. 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 10 Today you have been performing transabdominal ultrasound of the pelvis. What are the other two routes for imaging of the pelvis using ultrasound? What is the most common reason for ultrasound examination of a uterus? Why might ultrasound scanning be used in relation to contraceptive devices? Notes 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 11 Checklist By the end of the session, you should be able to: Describe and draw the surface marking projections of bones of the pelvis Describe and draw the orientation of organs within the pelvis Describe the anatomy of the pelvis as viewed through ultrasound o Displaying an understanding of the different structures which can be seen in biologically male, female and intersex individuals Apply an understanding of the arrangement of pelvic viscera to clinical scenarios 204 – Living Anatomy and Ultrasound (DO’B) 4/14/2024 12