Female Pelvis and Pelvic Floor (KEATS)

Female pelvis Strong bony structure which articulates the lumbar vertebrae superiorly and femoral heads laterally Enables movements Protects pelvic organs Pelvic floor muscles are attached to pelvis which help support bladder, vagina, uterus and rectum Four bones (adult): o Two...

Female pelvis Strong bony structure which articulates the lumbar vertebrae superiorly and femoral heads laterally Enables movements Protects pelvic organs Pelvic floor muscles are attached to pelvis which help support bladder, vagina, uterus and rectum Four bones (adult): o Two pelvic/hip/coxal/innominate bones o One sacrum o One coccyx Four joints o Two sacroiliac joints o Symphysis pubis Reproduced from: Anatomy and Physiology in Healthcare by Marshall et al. ISBN: 97819079042958 © Scion Publishing Ltd, 2017 o Sacrococcygeal joint 1 Pelvic girdle The pelvic bones unite anteriorly (symphysis pubis) and meet the sacrum posteriorly (sacroiliac joints) Three bones that meet in a deep socket (acetabulum) which forms part of the hip joint with the head of the femur The ilium forms the superior flattened part of the pelvic bone Ischial spine The ischium is much smaller and forms the Ischial spine inferior part of the pelvic bone. Ischial tuberosities can be felt through buttocks when sitting Ischial tuberosity Ischial spines can be felt vaginally and are Ischial tuberosity used to define descent of the fetus The pubis is the smallest part and forms the Reproduced from: Anatomy and Physiology in Healthcare by Marshall et al. ISBN: 97819079042958 anterior part of the pelvic bone Blood vessels and nerves pass throughthe © Scion Publishing Ltd, 2017 obturator foramen 2 True & false pelvis For midwifery purposes the pelvis is divided into the false pelvis above the iliopectineal line and the true pelvis below The shape and diameters of true pelvis are important in vaginal birth as the fetus rotates to aid it’s descent using the largest diameters Fig. 3.5 True and false pelvis. Reproduced from: Maternal Child The true pelvis consists of: Nursing Care by Perry o Pelvic brim (inlet) o Pelvic cavity o Pelvic outlet Fig. 16.4 True Pelvis. Reproduced from: Maternal-Child Nursing by McKinney 3 Pelvic brim Pelvic brim is oval in shape Landmarks are shown in figure 1. Sacral promontory 2. Sacral ala 3. Sacroiliac joint 4. Iliopectineal line 5. Iliopectineal eminence 6. Superior pubic ramus 7. Body of pubis bone 8. Symphysis pubis Figure 24.6 The pelvic brim. Reproduced from: Physiology in Childbearing by Rankin 4 Pelvic cavity Figure 27.7 Shape of pelvic cavity showing inclination. Reproduced The pelvic cavity extends from the brim from: Mayes’ Midwifery by MacDonald to the outlet Circular shape The pelvis is inclined due to the 55˚ curvature of the spine 15˚ Fetus has to follow a curve during vaginal birth called the curve of Carus The pelvic brim is at an angle of 55˚ to Fig 25 Curve of the horizontal Curve of Carus Carus. The pelvic outlet is at angle of only 15˚ Reproduced from: due to the differences in lengths of the Illustrated Dictionary of anterior (4.5 cm) and posterior walls Midwifery by (12cm) of the pelvis Gray 5 Pelvic outlet The pelvic outlet is ovoid/diamond shaped Landmarks are shown in figure: 1. Symphysis pubis 2. Pubic arch 3. Ischial spines (superior landmarks) and ischial tuberosities (inferior landmarks) 4. Sacrotuberous and sacrospinous ligaments 5. Coccyx Reproduced from: Essential Anatomy and Physiology in Matenity Care by Wylie 6 Pelvic Diameters Four principal diameters: o Anteroposterior diameter o Transverse diameter o Two oblique diameters Sacrocotyloid diameter extends from sacral Fig. 27.4 Average diameters of the female pelvis in cm. Reproduced from: Mayes’ Midwifery by MacDonald promontory to iliopectineal eminence on same side. Fig. 3.12 Pelvic brim showing Approx. 9-9.5cm diameters. Reproduced from: Myles Textbook for Midwives by Marshall 7 Pelvic conjugates Anatomical conjugate (~12cm) Obstetric conjugate – smallest diameter for the fetus to negotiate (~11cm) Diagonal/internal conjugate (~13cm) – can be estimated on vaginal examination Figure 27.6 The relationship of the pelvic conjugates and the fetal negotiation of the conjugates. Reproduced from: Mayes’ Midwifery by MacDonald 8 Pelvic floor Strong pelvic floor structure required to support pelvic contents due to upright posture (particularly during pregnancy) The pelvic floor is also involved in micturition, defaecation, sexual intercourse, labour and birth Pelvic floor consists of 2 layers of muscles, ligaments and connective tissue or deep muscles Fig 25.5 The layers of the pelvic floor. All reproduced from: Physiology in Childbearing by Rankin 9 Deep muscle layer (levator ani) The medial pubococcygeus muscles extend from the inner aspect of the pubic bone to the coccyx. They surround and support the urethra, lower third of the vagina and rectum Iliococcygeus muscles extend from the inner aspect of the iliac bone, and fibres from each side meet in the midline in the perineum, before extending to the coccyx. They support and maintain position of pelvic organs, resist intraabdominal pressure and pull the coccyx anteriorly after childbirth/defecation Ischiococcygeus muscles arise from the ischial spines and pass to the lower sacrum and upper coccyx. These muscles help support the sacroiliac and sacrococcygeal joints of the Fig. 1.7 Deep muscle layer of the pelvic floor. Reproduced from Myles pelvis Survival Guide to Midwifery by Raynor Blood is supplied from the pudendal arteries. Nerve supply is provided by the third and fourth sacral nerves 10 Superficial muscle layer Ischiocavernosus muscles extend from each ischial tuberosity to the clitoris Bulbocavernosus muscles arise in the perineum, pass around the vagina and embed in the clitoris Transverse perineal muscles (transverse perinei) extend from the ischial tuberosities to the perineum, where they join with muscles of the perineal body External anal sphincter External urethral sphincter Fig. 1.6 Superficial muscle layer of the pelvic floor. Reproduced from Myles Survival Guide to Midwifery by Raynor 11 Perineal body Area of skin, muscles and connective tissue between vulva and anus Vital part of the pelvic floor as many muscles join here: o Bulbocavernosus and transverse perinei of the superficial muscles o Pubococcygeus of the deep muscles Assists in the processes of vaginal birth and defecation Commonly torn (or incised) during childbirth which may require suturing Reproduced from: Anatomy and Physiology in Healthcare by Marshall et al. ISBN: 97819079042958 © Scion Publishing Ltd, 2017 12 Perineal trauma 1st degree tear - injury to the skin only 2nd degree tear - injury involving the perineal muscles but not the anal sphincter 3rd degree tear - injury to the perineum involving the anal sphincter: o 3a less than 50% of the External Anal Sphincter (EAS) thickness torn o 3b more than 50% of the EAS thickness torn o 3c EAS and Internal Anal Sphincter (IAS) torn 4th degree tear - injury to the anal sphincter complex (EAS and IAS) and anal epithelium Mediolateral episiotomy Figure 43.2 Position of a second-, third-, fourth-degree tear and episiotomy. Reproduced from: Mayes’ Midwifery by MacDonald 13 Physiological changes to the pelvis and pelvic floor Pregnancy Relaxing effect of progesterone and progesterone o Relaxing of the pelvic ligaments and joints slightly increases pelvic dimensions but may cause back pain and/or Pelvic Girdle Pain (PGP) o Relaxing of the pelvic floor muscles aids the process of vaginal birth but may lead to stress incontinence @hannahbphotographyuk 14 Physiological changes to the pelvis and pelvic floor Postnatal Pelvic ligaments and joints tighten quickly after birth Pelvic floor muscles need to regain their supporting function very quickly after being stretched significantly during labour and vaginal birth. Early ambulation and pelvic floor exercises can support recovery and prevent long terms problems such as urinary and fecal incontinence, dyspareunia and pelvic organ prolapse Increased blood flow may lead to oedema and bruising Perineal damage may be painful (pharmacological and non-pharmacological analgesia important) @hannahbphotographyuk 15 Pelvic girdle pain Pelvic girdle pain (PGP) is pain in the front and/or the back of your pelvis that can also affect other areas such as the hips or thighs. PGP can affect the symphysis pubis and/or the sacroiliac joints Used to be called symphysis pubis dysfunction (SPD) 1 in 5 (20%) of pregnant women and people will experience PGP Affects mobility and quality of life Referral to physiotherapist for assessment and treatment Treatment includes exercise advice and/or a non-rigid lumbopelvic belt (NICE NG201, 2021) 16 Incontinence During pregnancy, up to 60% of women experience urinary incontinence (stress and/or urge) Stress incontinence – urine leaks when pressure is exerted on the bladder (coughing, sneezing, exercising etc) Urge incontinence – sudden intense need to pass urine Up to 25% of women will still experience stress incontinence one year postpartum Pelvic floor exercises can reduce @alexafayebirthstories incidence Women with 3rd or 4th degree tears are a risk of fecal incontinence 17 Pelvic floor exercises All women, in the antenatal period, should be given evidence-based information and advice about pelvic floor muscle exercises Maternity services providers should develop clear standards and a referral pathway to specialist physiotherapy for women who are at risk of developing problems involving pelvic floor dysfunction. Specifically, those women with episiotomy, significant perineal tears including 3rd and 4th degree tears, suspected bladder or bowel injury during a caesarean section, forceps or ventouse delivery, and where there is a previous history of bladder/bowel or pelvic floor problems. Training and education should include issues of cultural imperatives and norms, religious beliefs and their relationship to the uptake of services, that meets the criteria for a culturally competent service as defined by the NHS. 18