Renal Nervous Anatomy Flashcards
What are the 3 Normal Motor Functions of the Renal System?
- Ureteric Peristalsis
- Bladder Contraction
- Urethral Sphincter Control (internal and external urethral sphincters)
List areas from which sensory renal pain can arise
Kidneys Ureters Bladder Urethra Testis (not technically a part of the Renal System)
What is Urinary Continence?
The Voluntary Control of the elimination of Urine from the Bladder
What do the Nerves of the Lumbar and Sacral Plexus supply?
Perineum (distal part of the renal system) and the Lower Limbs
What are the 5 Modalities of the Nerve Fibres?
Somatic Sensory Visceral Afferent Somatic Motor Parasympathetic Sympathetic
What is Somatic Sensory?
When Sensations from the Body Wall (i.e. The External Environment) are conveyed to the CNS
What is Visceral Afferent?
When Sensations from the Visceral Organs (i.e. The Internal Environment) are conveyed to the CNS
What is Somatic Motor?
When Motor Responses to our Body Wall (i.e. The External Environment) are conveyed from the CNS to stimulate Skeletal Muscle Contractions
What are the Sympathetics and Parasympathetics?
Motor Responses to the Organs Visceral Organs (i.e. The Internal Environment) are conveyed from the CNS to stimulate Smooth Muscle, Cardiac Muscle and Glands
What Nerve Modality controls Ureteric Peristalsis and Bladder Contraction?
Sympathetics and Parasympathetics
What Nerve Modality controls the Urethral Sphincter?
Somatic Motor to the External Urethral Sphincter and Levator Ani
What Nerve Modality results in Sensory Renal Pain?
Visceral Afferent
N.B. Perineal Urethral Pain is driven by Somatic Sensory
Testes also have some Somatic Sensory presentation too.
What Nerve Modality controls the Voluntary Elimination of Urine from the Bladder?
COMBINATION
Somatic Motor
Visceral Afferent
Sympathetics and Parasympathetics
Which Nerve Modalities is involved in the Lumbar and Sacral Plexuses?
Somatic Sensory
Somatic Motor
How can Nerves communicate with the CNS?
For ANY type of Nerve Fibre to be able communicate with the CNS, it needs to be carried WITHIN the Cranial/Spinal Nerves.
The Distance a Type of Nerve Fibre is carried within a Cranial/Spinal Nerve Fibre will differ.
Which Nerve Fibres are carried the Entire Length of the Cranial/Spinal Nerves?
Somatic Motor
Somatic Sensory
Carried from Origin to Destination
Which Nerve Fibres use the Cranial/Spinal Nerve Fibres for Limited Portions to get in and out of the CNS?
Sympathetics and Parasympathetics
Visceral Afferents
What is the ONLY Point at which the Sympathetic Nerve Fibres leave the CNS?
T1-L2 Vertebral Levels
a.k.a. Thoracolumbar Outflow
Through which nerves do Sympathetic Fibres reach the Smooth Muscle/Glands of the Body Wall?
Spinal Nerves
N.B. NOT the case for the Smooth Muscle or Glands of the Head!
Through which nerves do Sympathetic Fibres reach the Smooth Muscle/Glands of the Body?
Splanchnic Nerves (Cardiopulmonary or Abdominopelvic)
How do Sympathetic Fibres reach the Smooth Muscle/Glands of the Head?
By hitching a ride on the Arteries that supply the same structures
How Do Sympathetic Nerve Fibres get from the CNS to the Kidneys, Ureters & Bladder?
Leave the Spinal Cord between Levels T10 - L2
Enter the Sympathetic Chain bilaterally but do NOT Synapse
Then leave the Sympathetic Chain via the Abdominopelvic Splanchnic Nerves
Synapse at the Abdominal Sympathetic Ganglia located around the AA
Postsynaptic Sympathetic Nerves pass from Ganglia towards the Periarterial Plexus to supply the Kidneys, Ureters & Bladder
How do the Parasympathetic Nerve Fibres leave the CNS?
Only within the 4 Cranial Nerves (III, VII, IX and X) and the Sacral Spinal Nerves
(a.k.a. Craniosacral Outflow)
Do Parasympathetic Fibres innervate the smooth muscle/glands of the body wall?
NO.
How do the Parasympathetic Fibres reach the smooth muscle/glands of the head and body?
Via the Cranial Nerves
More specifically, how do the Parasympathetic Fibres reach the smooth muscle/glands of the hindgut and pelvic organs
Via the Pelvic Splanchnic Nerves
How Do Parasympathetic Nerve Fibres get from the CNS to the Kidneys, Ureters & Bladder?
Parasympathetic Nerve Fibres which innervate the Kidneys & Ureter are carried within CN X
Parasympathetic Nerve Fibres which innervate the Bladder are carried within the Pelvic Splanchnic Nerves
From which Spinal Nerves do the Pelvic Splanchnic Nerves arise?
Spinal Nerves S2, S3 and S4
What Nerve Modalities are contained within the Sacral Plexus?
Sympathetic and Parasympathetic
Visceral Afferent
How Do Somatic Motor Nerve Fibres get from the CNS to the Kidneys, Ureters & Bladder?
Trick Question!
Somatic Motor Fibres only go to Body WALL Structures.
Somatic Motor only supplies structures within the Perineum i.e. Perineal Urethra, External Urethral Sphincter and Levator Ani
Where is Pain from the Kidney itself usually felt?
In the Loin i.e. Posterior Aspect of the Flank Region, on the Affected Side
Where is Pain from the Bladder usually felt?
Midline of the Suprapubic Region
Where is Pain from the Perineal Urethra usually felt?
Quite localised in the Perineum
What is Characteristic of the Pain from an Obstructing Calculus?
Radiating Pain from the Loin to Groin on the Affected Side
How Do Visceral Afferent Nerve Fibres get from the Kidneys to the CNS?
Visceral Afferents from the kidneys run alongside the Sympathetic Fibres back to the Spinal Cord, entering it between the T11 - L1 Levels
Therefore, the patient feels Renal Pain in these Dermatomes, Posteriorly (i.e. the “Loin”)
What is the Differential Diagnosis of Loin Pain?
Muscular (Most Common) Vertebral Spinal Nerve Root Compression Lower Lobe Pneumonia Skin e.g. Herpes Zoster
How Do Visceral Afferent Nerve Fibres get from the Ureters to the CNS?
Visceral Afferents from the Ureters run alongside the Sympathetic Fibres back to the Spinal Cord, entering between Levels T11 - L2
Pain from these structures tends to be perceived by the Patient anywhere along this path
What is the Differential Diagnoses for Groin Pain?
Femoral/Inguinal Hernias
Lymphadenopathy
Testicular Pathology
How Do Visceral Afferent Nerve Fibres get from the Bladder to the CNS?
Visceral Afferents carrying Pain from the Superior Part of the Bladder run alongside the Sympathetic Fibres back to the Spinal Cord,
entering between levels T11 – L2.
Pain is perceived by the Patient as Suprapubic Midline Pain.
Visceral Afferent Fibres from the rest of the Bladder run alongside the Parasympathetic Fibres back to Spinal Cord Levels S2,S3, S4
What is the Differential Diagnoses for Suprapubic Pain?
Hindgut Organs e.g. Sigmoid Diverticula
Other Single, Midline Pelvic Organs whose Superior Aspect touches the Peritoneum, e.g. Uterus
How Do Visceral Afferent Nerve Fibres get from the Urethra to the CNS?
visceral afferents from the proximal urethra (i.e. above the levator Ani and in the Pelvis) run alongside the Parasympathetic Nerve fibres back to Spinal Cords Levels S2,S3,S4
How Do Somatic Sensory Nerve Fibres get from the Urethra to the CNS?
Somatic Sensory Nerve Fibres from the Remaining Urethra are carried within the Pudendal Nerve, back to Spinal Cord Levels S2,S3,S4.
What is the Differential Diagnoses of Perineal Pain?
Vaginal Tears
Anal Canal Fissures
Perineal Genital Ulcer e.g. Herpes
How Do Pain Fibres get from the Testis to the CNS?
due to its embryological descent, visceral afferents run alongside sympathetic fibres back to the spinal cord to levels T10-11
however, due to its close relationship to the scrotal wall (body wall), pain from the testis can also present localised to the scrotum and/or groin (L1 region)
What is the Differential Diagnoses of Scrotal Pain?
Skin Lesions
Strangulated Inguinal Hernia
How would Patients describe Pain from the Kidneys?
Dull, Achy type Pain in the Loin
How would Patients describe Pain from the Ureters?
If Obstruction is present, the classic is Radiation from the Loin to the Groin
How would Patients describe Pain from the Bladder?
Dull, Achy Suprapubic Pain
How would Patients describe Pain from the Urethra?
If originating in the Perineal Urethra, pain is Relatively Sharp and Localised
How would Patients describe Pain from the Testes?
Pain often felt in the Scrotum which can radiate to the Groin and Anterior Lower Abdomen or can present in 1 of the Latter 2 WITHOUT Radiation
What are the Nerves involved in Controlling Urine Flow?
Nerves that enter and leave the Spinal Cord at Levels S2-S4
Pelvic Splanchnic Nerves
Pudendal Nerve
Visceral Afferent Fibres
What happens to the Urinating Reflex in Potty Trained Children and Adults?
Reflex is Overridden as Action Potentials within Inhibitory nerve Fibres pass the Cortex inferiorly and inhibit this reflex.
Also, there is Voluntary Contraction of the EUS and Levator Ani Muscles
Reflex inhibition stops when urination is appropriate
What happens in Urination after Inhibition of the Reflex occurs?
Co-ordinated parasympathetic contraction of the Detrusor muscle
Somatic motor relaxation of the EUS and Levator Ani Muscles
Somatic Motor Contraction of the Anterior Abdominal Wall
What is the Origin of the Sciatic Nerve?
Sacral Plexus from Nerve Roots L4-S3
