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 fibers originate from the spinal cord levels T10 to L2 and reach the ureters via the following plexuses:
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 input stimulates smooth muscle contraction and promotes ureteric peristalsis, helping propel urine toward the bladder.
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) |
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.