Podcast
Questions and Answers
What bones comprise the pelvic girdle?
What bones comprise the pelvic girdle?
Which ligaments are crucial for preventing rotation of the sacrum at the sacroiliac joints?
Which ligaments are crucial for preventing rotation of the sacrum at the sacroiliac joints?
Which muscle is a major component of the pelvic diaphragm?
Which muscle is a major component of the pelvic diaphragm?
What is the significance of the pelvic inlet in childbirth?
What is the significance of the pelvic inlet in childbirth?
Signup and view all the answers
What dimension measures the distance between the two ischial spines?
What dimension measures the distance between the two ischial spines?
Signup and view all the answers
How can fecal incontinence arise from injury to a specific muscle?
How can fecal incontinence arise from injury to a specific muscle?
Signup and view all the answers
Which structure is essential in the development of the sacral plexus?
Which structure is essential in the development of the sacral plexus?
Signup and view all the answers
What defines the boundaries of the 'true' pelvis?
What defines the boundaries of the 'true' pelvis?
Signup and view all the answers
What is characteristic of the gynecoid pelvic form?
What is characteristic of the gynecoid pelvic form?
Signup and view all the answers
Which of the following nerves is NOT part of the sacral plexus?
Which of the following nerves is NOT part of the sacral plexus?
Signup and view all the answers
Which description best fits the anthropoid pelvic form?
Which description best fits the anthropoid pelvic form?
Signup and view all the answers
Which of the following correctly identifies the components of the lumbosacral trunk?
Which of the following correctly identifies the components of the lumbosacral trunk?
Signup and view all the answers
Which function is NOT provided by the lumbosacral plexus?
Which function is NOT provided by the lumbosacral plexus?
Signup and view all the answers
Which of the following diameters is NOT associated with the pelvic inlet?
Which of the following diameters is NOT associated with the pelvic inlet?
Signup and view all the answers
What are the three fused bones that make up the hip bone?
What are the three fused bones that make up the hip bone?
Signup and view all the answers
Which structure does NOT pass through the pelvic inlet?
Which structure does NOT pass through the pelvic inlet?
Signup and view all the answers
What is the anatomical term for the hip bone?
What is the anatomical term for the hip bone?
Signup and view all the answers
Which part of the ilium contributes to the formation of the acetabulum?
Which part of the ilium contributes to the formation of the acetabulum?
Signup and view all the answers
Which feature is associated with the ala of the ilium?
Which feature is associated with the ala of the ilium?
Signup and view all the answers
What is the informal name given to the hip bone due to its shape?
What is the informal name given to the hip bone due to its shape?
Signup and view all the answers
The ilium is divided into which two main parts?
The ilium is divided into which two main parts?
Signup and view all the answers
Which surface of the ilium articulates with the sacrum?
Which surface of the ilium articulates with the sacrum?
Signup and view all the answers
The term 'synostosis' refers to which aspect of the hip bone?
The term 'synostosis' refers to which aspect of the hip bone?
Signup and view all the answers
What comprises the bony pelvis?
What comprises the bony pelvis?
Signup and view all the answers
Which structure forms the pelvic inlet?
Which structure forms the pelvic inlet?
Signup and view all the answers
What is the main function of the pelvic girdle?
What is the main function of the pelvic girdle?
Signup and view all the answers
Which of the following is NOT found in the greater pelvis?
Which of the following is NOT found in the greater pelvis?
Signup and view all the answers
How does the female pelvis differ from the male pelvis?
How does the female pelvis differ from the male pelvis?
Signup and view all the answers
Which structures are involved in the formation of the pelvic inlet?
Which structures are involved in the formation of the pelvic inlet?
Signup and view all the answers
Where is the lesser pelvis located in relation to the greater pelvis?
Where is the lesser pelvis located in relation to the greater pelvis?
Signup and view all the answers
Which organ is primarily contained within the lesser pelvis?
Which organ is primarily contained within the lesser pelvis?
Signup and view all the answers
What do the sacrococcygeal and sacroiliac joints connect?
What do the sacrococcygeal and sacroiliac joints connect?
Signup and view all the answers
What is the role of the linea terminalis in the pelvis?
What is the role of the linea terminalis in the pelvis?
Signup and view all the answers
What lies along the posterior gluteal line?
What lies along the posterior gluteal line?
Signup and view all the answers
Which iliac crest lip is associated with the abdominal wall muscle attachment?
Which iliac crest lip is associated with the abdominal wall muscle attachment?
Signup and view all the answers
What is the function of the dimples of Venus?
What is the function of the dimples of Venus?
Signup and view all the answers
What feature does the pubic tubercle primarily provide?
What feature does the pubic tubercle primarily provide?
Signup and view all the answers
In which section does the superior pubic ramus contribute to the acetabulum?
In which section does the superior pubic ramus contribute to the acetabulum?
Signup and view all the answers
Which structure acts as the medial surface articulating at the pubic symphysis?
Which structure acts as the medial surface articulating at the pubic symphysis?
Signup and view all the answers
Which line marks the inferior border for gluteus minimus origin?
Which line marks the inferior border for gluteus minimus origin?
Signup and view all the answers
What do the three lips of the iliac crest allow for?
What do the three lips of the iliac crest allow for?
Signup and view all the answers
What is the shape of the rami when viewed anteriorly?
What is the shape of the rami when viewed anteriorly?
Signup and view all the answers
What is the role of the arcuate line in the ilium?
What is the role of the arcuate line in the ilium?
Signup and view all the answers
What is the main function of the pelvic girdle?
What is the main function of the pelvic girdle?
Signup and view all the answers
Which of the following accurately defines the boundaries of the pelvic inlet?
Which of the following accurately defines the boundaries of the pelvic inlet?
Signup and view all the answers
What differentiates the greater pelvis from the lesser pelvis?
What differentiates the greater pelvis from the lesser pelvis?
Signup and view all the answers
Which bones compose the bony pelvis?
Which bones compose the bony pelvis?
Signup and view all the answers
What is the function of the linea terminalis in the pelvis?
What is the function of the linea terminalis in the pelvis?
Signup and view all the answers
Which organ is primarily contained within the lesser pelvis?
Which organ is primarily contained within the lesser pelvis?
Signup and view all the answers
What is the significance of the pelvic cavity?
What is the significance of the pelvic cavity?
Signup and view all the answers
Which statement is true about the differences in female and male pelvises?
Which statement is true about the differences in female and male pelvises?
Signup and view all the answers
What is the primary function of the inferior gluteal nerve?
What is the primary function of the inferior gluteal nerve?
Signup and view all the answers
A positive Trendelenburg sign indicates which type of nerve dysfunction?
A positive Trendelenburg sign indicates which type of nerve dysfunction?
Signup and view all the answers
Which anatomical structure does the posterior cutaneous nerve of the thigh NOT innervate?
Which anatomical structure does the posterior cutaneous nerve of the thigh NOT innervate?
Signup and view all the answers
Which of the following describes the function of the inferior clunial nerve?
Which of the following describes the function of the inferior clunial nerve?
Signup and view all the answers
What impairment is associated with paresis of the inferior gluteal nerve?
What impairment is associated with paresis of the inferior gluteal nerve?
Signup and view all the answers
Which component of the ilium serves as the origin of the iliacus muscle?
Which component of the ilium serves as the origin of the iliacus muscle?
Signup and view all the answers
What structure serves as the attachment point for the posterior interosseous sacro-iliac ligament?
What structure serves as the attachment point for the posterior interosseous sacro-iliac ligament?
Signup and view all the answers
What term describes the fusion of the ilium, ischium, and pubis in the hip bone?
What term describes the fusion of the ilium, ischium, and pubis in the hip bone?
Signup and view all the answers
Which of the following is NOT a diameter associated with the pelvic inlet?
Which of the following is NOT a diameter associated with the pelvic inlet?
Signup and view all the answers
Which part of the hip bone is considered the most superior?
Which part of the hip bone is considered the most superior?
Signup and view all the answers
What informal name is given to the hip bone due to its unique shape?
What informal name is given to the hip bone due to its unique shape?
Signup and view all the answers
Which of the following features is part of the ala of the ilium?
Which of the following features is part of the ala of the ilium?
Signup and view all the answers
What is the cup-shaped hollow on the outer aspect of the hip bone called?
What is the cup-shaped hollow on the outer aspect of the hip bone called?
Signup and view all the answers
Which structure passes through the pelvic inlet?
Which structure passes through the pelvic inlet?
Signup and view all the answers
In the context of the hip bone, which of the following has the role of providing articulation with the sacrum?
In the context of the hip bone, which of the following has the role of providing articulation with the sacrum?
Signup and view all the answers
What anatomical feature distinguishes the gynecoid pelvic form from others?
What anatomical feature distinguishes the gynecoid pelvic form from others?
Signup and view all the answers
What is the primary function of the superior gluteal nerve?
What is the primary function of the superior gluteal nerve?
Signup and view all the answers
Which pelvic form is most commonly associated with male individuals?
Which pelvic form is most commonly associated with male individuals?
Signup and view all the answers
Which of the following nerves is a part of the sacral plexus?
Which of the following nerves is a part of the sacral plexus?
Signup and view all the answers
What characteristic is associated with the anthropoid pelvic form?
What characteristic is associated with the anthropoid pelvic form?
Signup and view all the answers
Which nerve passes through the infrapiriform foramen?
Which nerve passes through the infrapiriform foramen?
Signup and view all the answers
What anatomical feature does the piriformis muscle divide?
What anatomical feature does the piriformis muscle divide?
Signup and view all the answers
Which of the following is NOT a function of the lumbosacral plexus?
Which of the following is NOT a function of the lumbosacral plexus?
Signup and view all the answers
Which component forms the lumbosacral trunk?
Which component forms the lumbosacral trunk?
Signup and view all the answers
What anatomical feature separates the origins of the gluteus maximus and medius?
What anatomical feature separates the origins of the gluteus maximus and medius?
Signup and view all the answers
Which structure serves as the attachment site for the inguinal ligament?
Which structure serves as the attachment site for the inguinal ligament?
Signup and view all the answers
Which iliac crest lip is primarily associated with the muscles of the abdominal wall?
Which iliac crest lip is primarily associated with the muscles of the abdominal wall?
Signup and view all the answers
What is the shape of the rami of the pubis when viewed anteriorly?
What is the shape of the rami of the pubis when viewed anteriorly?
Signup and view all the answers
Which line marks the caudal border for the origin of the gluteus minimus?
Which line marks the caudal border for the origin of the gluteus minimus?
Signup and view all the answers
What is primarily formed by the superior pubic ramus?
What is primarily formed by the superior pubic ramus?
Signup and view all the answers
Which ligament contributes to the formation of the dimples of Venus?
Which ligament contributes to the formation of the dimples of Venus?
Signup and view all the answers
Which structure is considered the medial surface of the pubis that articulates at the pubic symphysis?
Which structure is considered the medial surface of the pubis that articulates at the pubic symphysis?
Signup and view all the answers
Which part of the iliac crest is a bony projection formed by the origin of the gluteus medius?
Which part of the iliac crest is a bony projection formed by the origin of the gluteus medius?
Signup and view all the answers
What anatomical term is used for the lateral lumbar indentations known as the dimples of Venus?
What anatomical term is used for the lateral lumbar indentations known as the dimples of Venus?
Signup and view all the answers
Study Notes
Pelvic Girdle
- The pelvic girdle consists of the left and right hip bones, sacrum, and coccyx.
- The pelvic bones connect via the pubic symphysis anteriorly, sacrococcygeal and sacroiliac joints posteriorly.
Functions of the Pelvic Girdle
- Transmits body weight from the axial skeleton to the lower extremities.
- Provides attachment to a large number of muscles.
- Contains and protects the abdominopelvic and pelvic viscera.
Pelvic Inlet
- Separates the abdominal and pelvic cavities.
- Located at the superior rim of the pelvic cavity.
- Borders include: sacral promontory, sacral wings, arcuate line of ilium, pectineal line of pubis, and pubic symphysis.
- Structures passing through: ureter, spermatic cord, round ligament of the uterus, suspensory ligament of the ovary, median sacral vessels, gonadal vessels, iliolumbar vessels, lumbosacral trunk, sympathetic trunk, obturator nerve.
Hip Bone - Os Coxae
- Consists of three fused bones: ilium, ischium, and pubis.
- The bones fuse at the acetabulum.
- It articulates with the opposite hip bone anteriorly and the sacrum posteriorly.
Ilium - Os Ilium
- Most superior component of the hip bone.
- Divided into body and ala (wing).
- The body contributes to the acetabulum formation.
- The ala has four borders and three surfaces:
- Iliac fossa (origin of iliacus muscle).
- Sacropelvic surface: contains the auricular surface (articulates with the sacrum) and iliac tuberosity (attachment of posterior interosseous sacroiliac ligament).
- Gluteal surface (origin of gluteal muscles): includes the posterior, anterior, and inferior gluteal lines, which demarcate origin areas of different gluteal muscles.
- Iliac crest: has three lips for attachment of abdominal wall muscles (outer, intermediate, inner). It also includes the tuberculum of iliac crest (origin of gluteus medius), anterior superior and inferior iliac spine, and posterior superior and inferior iliac spine.
Pubis - Os Pubis
- Located anteromedially.
- Has a body, superior pubic ramus, and inferior pubic ramus.
- The body connects to the pubic symphysis.
- The superior pubic ramus forms the ventral portion of the acetabulum.
Pelvic Form
- Gynecoid (most common female form): transverse oval inlet, wide sacrum, wide sacrosciatic notch, straight side walls, wide subpubic angle.
- Android (most common male form): triangular inlet, converging side walls, narrow sacrosciatic notch, narrow subpubic angle.
- Anthropoid (common in males): long anterior-posterior diameters, short transverse diameters, wide sacrosciatic notch, narrow subpubic angle.
- Platypelloid (flat variation of gynecoid): short anterior-posterior diameters, long transverse diameters, narrow sacrosciatic notch, wide subpubic angle.
Innervation of the Lower Limb
- The lower limb is innervated by branches of the lumbosacral plexus.
- The lumbosacral plexus is formed by the lumbar and sacral plexuses.
- Lumbar plexus: formed by T12 and L1-L4 nerves.
- Sacral plexus: formed by L4-L5 and S1-S4 nerves.
- The lumbosacral trunk is formed by the fusion of L4 and L5 and contributes to the sacral plexus.
Sacral Plexus
- Arises from S1-S4 nerve roots and receives contributions from L4 and L5 via the lumbosacral trunk.
- Located on the pelvic surface of the sacrum.
- Provides somatomotor and somatosensory innervation to the lower limb.
Branches of the Sacral Plexus
-
Superior gluteal nerve (L4-S1): innervates gluteus medius, gluteus minimus, and tensor fasciae latae, passes through the suprapiriform foramen.
-
Inferior gluteal nerve (L5-S2): innervates gluteus maximus.
-
Posterior cutaneous nerve of thigh (S1-S3): innervates skin of the posterior thigh.
-
Pudendal nerve (S2-S4): innervates external genitalia, perineum, pelvic floor muscles, and anal sphincter.
-
Sciatic nerve (L4-S3): major nerve of the lower limb.
-
The piriformis muscle divides the greater sciatic foramen into the suprapiriform foramen and the infrapiriform foramen.
Pelvic Girdle
- The pelvic girdle is made up of the two hip bones, the sacrum, and the coccyx.
- The hip bones are made up of three fused bones: the ilium, the ischium, and the pubis.
- The sacrum and coccyx are actually variably fused vertebrae.
- The pelvic girdle transmits body weight from the axial skeleton to the lower extremities.
- It provides attachment to numerous muscles and contains and protects the abdominopelvic and pelvic viscera.
Pelvic Inlet
- The pelvic inlet is the plane that separates the abdominal and pelvic cavities.
- It’s located at the superior rim of the pelvic cavity (upper pelvic aperture).
- The pelvic inlet is made up of the sacral promontory, sacral wings, arcuate line, pectineal line, and pubic symphysis.
- Structures passing through the pelvic inlet include the ureter, spermatic cord, round ligament of the uterus, suspensory ligament of the ovary, median sacral vessels, gonadal vessels, iliolumbar vessels, lumbosacral trunk, sympathetic trunk, and obturator nerve.
Greater Pelvis
- The greater pelvis, also known as the false pelvis, is located superiorly.
- It provides support for the lower abdominal viscera, such as the ileum and sigmoid colon.
- It has little obstetric relevance.
Lesser Pelvis
- The lesser pelvis, also known as the true pelvis, is located inferiorly.
- The pelvic cavity, which is the space within the pelvic girdle, resides within the lesser pelvis.
- The pelvic cavity contains abdominal and pelvic organs and is protected by the pelvic girdle.
Ilium
- The ilium is the most superior component of the hip bone.
- It consists of two main parts, the body and the ala (wing).
- The body contributes to the formation of the acetabulum.
- The ala is expanded and has four borders and three surfaces.
- The iliac fossa is the ventromedial concave fossa, which is the origin of the iliacus muscle.
- The sacropelvic surface is the medial surface behind and below the iliac fossa.
- The auricular surface articulates with the sacrum.
- The iliac tuberosity is the attachment of the posterior interosseous sacro-iliac ligament.
- The gluteal surface is the dorsolateral surface and is the origin of the gluteal muscles.
- The anterior, posterior, and inferior gluteal lines mark borders between the origins of the gluteus maximus, medius, and minimus muscles.
- The iliac crest has three lips: the outer lip, the intermediate zone, and the inner lip, which are attachment points for the abdominal wall muscles.
- The tubercle of the iliac crest is a bony projection formed by the origin of the gluteus medius muscle.
Ischium
- The ischium is the inferior component of the hip bone and forms the posterior part of the acetabulum.
- The ischial spine, ischial tuberosity, and ischial ramus are important anatomical structures of the ischium.
Pubis
- The pubis is the anterior component of the hip bone and contributes to the formation of the acetabulum.
- The pubic body connects to the pubic symphysis.
- The pubic tubercle is an attachment point for the inguinal ligament and superior pubic ligament.
- The pubic crest is the insertion of the rectus abdominis muscle and the origin of the pyramidalis muscle.
- The symphysial surface articulates at the pubic symphysis.
- The superior pubic ramus forms the ventral 1/3 of the acetabulum.
- The obturator crest is located between the pubic tubercle and acetabular notch.
- The pecten pubis forms part of the linea terminalis.
Pelvic Form
- There are four main pelvic forms: gynecoid, android, anthropoid, and platyelpelloid.
- The gynecoid form, most common in females, is characterized by a transverse oval inlet, wide sacrum, wide sacrosciatic notch, straight side walls, and wide subpubic angle.
- The android form, most common in males, is characterized by a triangular inlet, converging side walls, narrow sacrosciatic notch, and narrow subpubic angle.
- The anthropoid form, common in male individuals, is characterized by long anterior-posterior diameters, short transverse diameters, wide sacrosciatic notch, and narrow subpubic angle.
- The platyelpelloid form, a flat variation of the gynecoid type, is characterized by short anterior-posterior diameters, long transverse diameters, narrow sacrosciatic notch, and wide subpubic angle.
Lumbosacral Plexus
- The lumbosacral plexus is a network of nerves composed of two distinct plexuses: the lumbar plexus and the sacral plexus.
- The lumbar plexus is formed by the subcostal nerve (T12) and the first four lumbar nerves (L1–L4).
- The sacral plexus is formed by the last two lumbar nerves (L4–L5) and the first four sacral nerves (S1–S4).
- The lumbosacral trunk is formed by the fusion of lumbar nerves L4 and L5 and contributes to the sacral plexus.
Sacral Plexus (L4–S4)
- The sacral plexus arises from the spinal nerves of S1 to S4 and receives contributing branches from L4 and L5 via the lumbosacral trunk.
- It is located on the pelvic surface of the sacral bone.
- Along with the lumbar plexus, it provides somatomotor and somatosensory innervation to the lower limb.
Nerves of the Sacral Plexus
- The sacral plexus includes the superior gluteal nerve, inferior gluteal nerve, posterior cutaneous nerve of the thigh, pudendal nerve, and sciatic nerve.
- The piriformis muscle divides the greater sciatic foramen into the suprapiriform foramen and the infrapiriform foramen.
Superior Gluteal Nerve (L4–S1)
- The superior gluteal nerve runs through the suprapiriform foramen with the superior gluteal artery and veins.
- It innervates the gluteus medius, gluteus minimus, and tensor fasciae latae muscles.
Inferior Gluteal Nerve (L5–S2)
- The inferior gluteal nerve runs through the infrapiriform foramen with the inferior gluteal artery and veins.
- It innervates the gluteus maximus muscle.
Posterior Cutaneous Nerve of Thigh (S1–S3)
- The posterior cutaneous nerve of the thigh runs through the infrapiriform foramen.
- It provides somatosensory innervation to the dorsal thigh.
- It distally travels with the cranial extension of the small saphenous vein.
- It contains inferior clunial nerves, which provide somatosensory innervation to the distal part of the gluteal region.
- It contains perineal branches, which provide somatosensory innervation to the perineal skin.
Pudendal Nerve (S2–S4)
- The pudendal nerve will be discussed in the lecture on the perineum.
Sciatic Nerve (L5–S2)
- The sciatic nerve, with contributions from L4 and S3, will be discussed in the lecture on the thigh.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge of the pelvic girdle, including its structure, functions, and components. This quiz covers key aspects about the hip bones and pelvic inlet, along with their anatomical significance. Perfect for students of anatomy and related fields.