Urinary continence and renal system pain Flashcards
What are the normal renal system motor functions?
Ureteric peristalsis
Bladder contraction
Urethral sphincter control (internal and external)
Where can renal system pain come from?
Kidneys Ureters Bladder Urethra Testis
What is urinary continence?
Voluntary control of the elimination from the bladder
What does the lumbar and sacral plexus supply?
Perineum and lower limbs
What are the 5 modalities of nerve fibres?
Somatic sensory - body wall
Somatic motor - motor to body wall muscles
Visceral afferent - sensory for organs
Parasymp/symp: motor to organs, smooth muscle and glands
What controls ureteric peristalsis and bladder contraction?
Symp/parasymp
What controls urethral sphincter control?
Symp/parasymp Somatic motor (external sphincter and levator ani)
What relays pain from the renal system?
Visceral afferent
Somatic sensory in perineum
What controls urinary continence?
Symp/parasymp/somatic motor/ visceral afferent
What relays motor and sensory from the perineum and lower limbs?
Somatic sensory/ somatic motor
Where can sympathetics leave the CNS?
T1-L2 - thoracolumbar
Within what will symp fibres reach the smooth muscle and glands of the body wall?
Spinal nerves
Within what will symp fibres reach the smooth muscle and glands of the body (outwith the body wall)?
Cardiopulmonary and abdominopelvic splanchnic nerves
Within what will symp fibres reach the smooth muscle and glands of the head?
Via hitching a ride on the arteries which supply the same structures
What ramus will symp nerves travel on?
ANTERIOR
How do symp fibres get from the CNS to the kidneys, ureters and bladder?
Leave via T10 and L2
Enter symp chains bilaterally but do not synapse
Leave chain in abdominopelvic splanchnic nerves
Synapse at abdominal symp ganglia located around abdo aorta
Postsynaptic fibres pass from ganglia onto surface of arteries which are heading towards organs they innervate on the periarterial plexus
What do the periarterial plexuses carry?
Symp fibres
Parasymp fibres
Visceral afferent nerve fibres
Where will parasymps leave the CNS?
CN 3,7,9,10
Sacral spinal nerves
How do parasympathetic fibres reach the smooth muscle and glands of the head and body?
Cranial nerves
How do parasympathetic fibres reach the smooth muscle and glands of the hindgut and pelvic organs?
Pelvic splanchnic nerves
How do parasymps reach the kidney and ureters?
Vagus nerve via periarterial plexus
How do the parasymps reach the bladder?
Pelvic splanchinic nerves - S2,3,4 via periarterial plexus
Are the kidneys, ureters and bladders supplies by somatic motor nerve fibres?
NO
Somatic fibres only go to body wall structures so will supply the structures within the perineum which includes the urethra, external urethral sphincter and levator ani
Where is kidney pain (e.g. acute hydronephrosis) felt?
Loin - posterior aspect of the flank on the affected side
Where is bladder pain felt?
Suprapubic region in the midline
Where is pain from a calculus obstructing the ureter felt?
Radiating from loin to groin on the affected side
Where can pain from the perineal part of the urethra be felt?
Localised in the perineum
What is the differential of loin pain?
Skin origin (herpes zoster) Muscular - most common differential Vertebrae Spinal nerve root compression Lower lobe pneumonia
How do visceral afferents get from the kidney to the CNS?
Run alongside symp fibres back to the spinal cord
Enter spinal cord around T11 and L1
Patient will feel this in dermatomes posteriorly - the loin
How do visceral afferents get from the ureters to the CNS?
Run alongside sympathetic fibres
Enter spinal cord between T11 and L2
Pain tends to be perceived anywhere along this path
Differential of groin pain
Hernias - inguinal or femoral
Lymphadenopathy
Testicular pathology
How do visceral afferents from the superior part of the bladder reach the CNS?
In contact with peritoneum:
travels with sympathetics back to T11-L2
How do visceral afferents from the rest of the bladder not touching the peritoneum reach the CNS?
Run along parasymps back to S2,3,4
Differential diagnosis of suprapubic pain
Hindgut organs - sigmoid diverticula
Other single, midline pelvic organs whose sup aspect touches the peritoneum e.g. uterus
How do visceral afferents from the proximal urethra reach the CNS?
Proximal urethra (above levator ani and in pelvis): runs along parasymps to S2,3,4
How do somatic sensory nerve fibres from the distal urethra reach the CNS?
Carried with pudendal nerve to S2,3,4
Localised pain within the perineum
Differential of perineal pain
Vaginal tear
Anal canal fissure
Perineal genital ulcer e.g. herpes
How do pain fibres from the testis reach the CNS?
Run along symps back to spinal cord levels T10-11
Due to close relationship with scrotum, can also present as localised pain to scrotum and/or groin in L1 region
Differential of scrotum pain
Skin lesion
Strangulated inguinal herina
What type of pain does kidney pathology cause?
Dull, achy pain in loin
What type of pain does ureter obstruction cause?
Loin to groin
What type of pain does bladder pathology cause?
Dull, achy suprapubic pain
What type of pain does distal urethra pathology cause?
Localised and sharp pain within the perineum
What type of pain does testis pathology cause?
Often felt in scrotum but can radiate to the groin and anterior lower abdo
What nerve fibres are key in controlling micturition?
S2,3,4
What will S2,3,4 spinal nerves carry?
Visceral afferents
Pelvis splanchinic carrying parasymps
Pudendal nerve carrying somatic sensory and motor
Describe urinary control
Bladder fills, sensed by stretch receptors of visceral afferents which is relayed to S2,3,4
Reflex is to empty bladder by stimulation of the detrusor muscle and inhibition of the internal sphincter
In those with urinary control however, the brain overrides this reflex, action potentials within inhibitory nerves fibres from cortex pass inferiorly and inhibit this reflex. There is also voluntary control of external anal sphincter and levator ani
Describe micturation
Cerebral inhibition lifted with a combined coordination of:
Contraction of detrusor (parasympathetic)
Internal urethral sphincter (parasymp), external urethral sphincter and levator ani (somatic motor) relax
Anterolateral abdo muscles contract to increase intra-abdominal pressure and force urine out of the external urethral orifice (somatic motor)
What nerves arise from the sacral plexus?
Pudendal nerve Sciatic nerve (from L4-S3)
What nerves does the lumbar plexus give off?
Iliohypogastric (L1) Ilioinguinal (L1) Lateral cutaneous nerve of thigh (L2,3) Genitofemoral nerve (L1,2) Femoral nerve (L2-4) Obturator nerve (L2-4)
What does the femoral nerve supply?
Passes under than inguinal ligament into the anterior compartment of thigh
What does the obturator nerve supply?
Passes through the obturator foramen into the medial compartment of thigh
Where does the sciatic nerve (L4-S3)run?
Posterior compartment of thigh via gluteal region
What nerve supplies sensation to the plantar aspect of the foot?
Tibial nerve
What nerve supplies the majority of the dorsum of the foot?
Superficial fibular nerve
What nerve supplies the 1st web space of the foot?
Deep fibular nerve
What nerve supplies the lateral aspect of the foot?
Sural nerve (formed from tibial and common fibular nerves)
What causes bladder contraction?
Parasymps from S2,3,4 to detrusor muscle
What is ureteric peristalsis?
Automatic action initiated and propagated by ureteric cells which have their own built in autorhythmicity rather than control of symp/parasymps
What controls the internal urethral sphincter?
Symp fibres causes it to contract during ejaculation
Parasymps to relax is to allow urine to flow through the urethra
What stimulates the external urethral sphincter to contract?
Somatic motor fibres within pudendal nerve
What simulates the levator ani muscle to contract?
Somatic motor within the nerve to levator ani (S3,4)
