Nerve Supply of the Ureters
Ureter nerves: sympathetic T11–L2 via renal/aortic plexus; parasympathetic via pelvic splanchnics.
The nerve supply of the ureters is autonomic and originates from both sympathetic and parasympathetic sources. These nerves regulate ureteric peristalsis and relay visceral pain sensations. The ureters do not require conscious control for function — their muscular contractions are coordinated reflexively through local and autonomic input.
Sympathetic Innervation
Sympathetic fibers originate from the spinal cord levels T10 to L2 and reach the ureters via the following plexuses:
- Renal plexus – for the upper ureter
- Aorticorenal and superior hypogastric plexuses – for the middle ureter
- Inferior hypogastric plexus – for the lower ureter
Sympathetic stimulation modulates vascular tone and may slow peristalsis in some contexts. Importantly, pain fibers (visceral afferents) accompanying these sympathetic nerves are responsible for referred pain in ureteric colic.
Parasympathetic Innervation
- Vagus nerve (CN X): Supplies parasympathetic input to the upper ureter
- Pelvic splanchnic nerves (S2–S4): Supply the lower ureter
Parasympathetic input stimulates smooth muscle contraction and promotes ureteric peristalsis, helping propel urine toward the bladder.
Sensory (Afferent) Innervation
Visceral sensory fibers run with sympathetic nerves (T10–L2), making pain poorly localized and often referred:
| Ureter Segment | Referred Pain Region |
|---|---|
| Upper ureter | Flank and lower back (T10–T12) |
| Middle ureter | Lower abdomen and inguinal region (T12–L1) |
| Lower ureter | Groin, scrotum/labia, and upper thigh (L1–L2, S2–S4) |
Clinical Significance
- Ureteric colic: Severe, colicky pain from stones is mediated via visceral afferents accompanying sympathetic fibers
- Referred pain: Explains why kidney stone pain radiates from the flank to the groin depending on stone location
- Autonomic reflexes: Ureteral stretch or injury can trigger reflex nausea, vomiting, or even bradycardia due to vagal involvement
- Surgical relevance: Damage to pelvic plexuses during hysterectomy or prostatectomy may impair lower ureteric function
The ureter’s nerve supply reflects its dual role in involuntary urine propulsion and visceral pain signaling. Understanding the autonomic and segmental innervation is essential for diagnosing ureteric pain and avoiding nerve injury during pelvic surgery.