4.5 Pelvis

Pelvic Anatomy and Musculature

Terms Related to Pelvis

  • Piriformis

  • Coccygeus

  • Obturator Internus

  • Iliococcygeus

  • Pubococcygeus

  • BMS/OTE645 - Unit IV: Focus on the Thoracic, Abdominal, and Pelvic Cavities

Reading Material

  • Chapter 6 covers various aspects of the pelvis, including:

    • Osteology of the pelvis and sacrum

    • Nerves and their origins in this region

    • Muscles and vascular supply

    • Organs and structures present

    • Clinical correlations associated with the pelvic region

Musculature from Posterior Abdominal Wall to Pelvis

  • Quadratus Lumborum

    • Origin: 12th rib to iliac crest

    • Action: Laterally flexes trunk

  • Psoas Minor

    • Note: Absent in 40% of individuals

    • Action: Weakly flexes lumbar spine

  • Psoas Major

    • Origin: T12-L5 to Lesser Trochanter of femur

    • Action: Flexes trunk, flexes hip

  • Iliacus

    • Origin: Iliac fossa to Lesser Trochanter of femur

    • Action: Flexes hip

  • Iliopsoas

    • Description: Strongest hip flexor

Lumbar Plexus

  • Comprised of anterior rami of lumbar spinal nerves

  • Structures to note in its association with the pelvis:

    • Lateral arcuate ligament

    • Lumbocostal trigone

    • Nerves such as Subcostal, Iliohypogastric, Ilioinguinal, Obturator, and Genitofemoral

    • Significant anatomical landmarks like the pelvis and lumbar vertebrae

Pelvic Anatomy

Pelvic Structures

  • True vs. False Pelvis: Understanding the distinction between these two regions is crucial

  • Coronal Section: Anterior inferior iliac spine, iliac fossa, iliac crest

  • Components: Ilium, Pubis, Ischium

  • Key Features:

    • Pubic arch, sacroiliac joints, acetabulum, sacrococcygeal joint, etc.

Joints of the Pelvic Girdle

  • Sacroiliac Joint: Major connection point of the pelvis

  • Pubic Symphysis: Between the left and right pubic bones

  • Sacro-Coccygeal Joint: Articulation between sacrum and coccyx

Ligaments Related to the Pelvis

  • Anterior Longitudinal Ligament

  • Iliolumbar Ligament

  • Sacrotuberous Ligament & Sacrospinous Ligament: Separate greater and lesser sciatic foramina

Pelvic Nerves and Their Origins

  • Major nerve roots involved in pelvic innervation include:

    • Pudendal Nerve (S2-S4): Main nerve of perineum

    • Function: Sensory innervation to external genitalia and motor supply to external urethral sphincter and anal sphincter

    • Pelvic Splanchnic Nerves: Parasympathetic contributions from S2-S4

    • Other critical nerves: Inferior gluteal nerve, nerve to piriformis, and genitofemoral nerve

Pelvic Floor Muscles

  • Pelvic Diaphragm: Composed of Levator Ani muscles and Coccygeus

    • Supports the pelvis

    • Important for urinary and fecal continence

  • Puborectalis muscle:

    • Forms a sling that creates an angle between the rectum and anal canal promoting fecal continence

Kegel Exercises

  • Purpose: Strengthen pelvic floor muscles to aid in urinary and fecal continence

  • Correct Method:

    • Identify pelvic floor muscles by stopping urination midstream

    • Tighten these muscles as if lifting a marble for three seconds, relax for three seconds

    • Repeat daily for best results

    • Avoid excessive abdominal or thigh muscle engagement during exercises

Blood Supply in the Pelvic Region

  • Internal Iliac Artery: Major supplier to pelvic organs

    • Branches:

    • Anterior Division: Umbilical, superior vesical, obturator, middle rectal, uterine, vaginal, and internal pudendal arteries

    • Posterior Division: Iliolumbar, lateral sacral, and superior gluteal arteries

Clinical Considerations

  • Pelvic Floor Dysfunction: Awareness of conditions like incontinence, pelvic organ prolapse, and other dysfunctions is critical

  • Surgical Relevance: Knowledge of pudendal nerve blocks during childbirth and surgical repairs

Neurovascular Structures of the Pelvis

  • Common Iliac Artery branches into Internal and External Iliac Arteries

  • Veins: Common Iliac vein pathways similar to arteries

Conclusion

  • Understanding the intricate anatomy of the pelvic region, including musculature, nerves, vasculature, and related clinical issues, is essential for medical and health professionals.

Liver Cirrhosis

Liver cirrhosis is a late-stage liver disease where healthy liver tissue is replaced by scar tissue, permanently damaging the liver and preventing it from functioning properly.

Causes

  • Chronic alcohol abuse: One of the most common causes, leading to alcoholic cirrhosis.

  • Chronic viral hepatitis (Hepatitis B and C): Long-term infection can cause inflammation and scarring.

  • Non-alcoholic fatty liver disease (NAFLD): A range of conditions caused by a buildup of fat in the liver, often associated with obesity, type 2 diabetes, and metabolic syndrome. When NAFLD progresses to inflammation and liver cell damage, it's called non-alcoholic steatohepatitis (NASH), which can lead to cirrhosis.

  • Autoimmune hepatitis: The body's immune system attacks liver cells.

  • Bile duct diseases: Such as primary biliary cholangitis (PBC) or primary sclerosing cholangitis (PSC), which damage the bile ducts.

  • Genetic disorders: Hemochromatosis (iron overload) and Wilson's disease (copper overload).

  • Certain medications: Prolonged use of some drugs can cause liver damage.

Symptoms

Symptoms often do not appear until liver damage is extensive. They can include:

  • Fatigue and weakness

  • Nausea and loss of appetite

  • Weight loss

  • Jaundice (yellowing of the skin and eyes)

  • Itchy skin

  • Swelling in the legs (edema) and abdomen (ascites) due to fluid retention

  • Easy bruising and bleeding

  • Confusion or drowsiness (hepatic encephalopathy)

  • Dark urine and pale stools

  • Spider-like blood vessels on the skin (spider angiomas)

Complications

  • Portal hypertension: Increased pressure in the blood vessels that supply the liver, leading to ascites and esophageal varices (enlarged veins in the esophagus that can bleed).

  • Hepatic encephalopathy: Buildup of toxins in the brain due to the liver's inability to filter them.

  • Liver cancer (hepatocellular carcinoma): Cirrhosis significantly increases the risk.

  • Kidney failure: Hepatorenal syndrome.

  • Increased risk of infections.

Diagnosis

  • Blood tests: To assess liver function and identify causes.

  • Imaging tests: Ultrasound, CT scan, MRI to visualize the liver.

  • Liver biopsy: To confirm the diagnosis and assess the extent of damage.

  • Elastography: A non-invasive test (such as FibroScan) that measures liver stiffness.

Treatment

Treatment focuses on managing symptoms, preventing further damage, and treating underlying causes.

  • Lifestyle changes: Avoiding alcohol, maintaining a healthy weight, and a balanced diet.

  • Medications: To manage complications like fluid retention, itching, and hepatic encephalopathy.

  • Treating the underlying cause: Antiviral drugs for hepatitis, immunosuppressants for autoimmune hepatitis.

  • Liver transplant: For end-stage cirrhosis where other treatments are ineffective and the patient meets criteria.

Prevention

  • Moderate alcohol consumption or abstinence.

  • Vaccinations for Hepatitis B.

  • Safe practices to prevent Hepatitis C transmission.

  • **Maintaining a healthy