sacral plexus
C2/ProfessionalTechnical/Medical
Definition
Meaning
A network of intersecting nerves located in the pelvic region near the sacrum, formed from the anterior rami of spinal nerves S1-S4 and part of S5, which supplies motor and sensory innervation to the pelvis, buttocks, genitals, thighs, legs, and feet.
In medical and anatomical contexts, the term specifically refers to one of the major nerve plexuses of the body, crucial for lower limb function and pelvic organ control. It is often discussed in relation to injuries, surgical procedures, or neurological conditions affecting the lower back and legs.
Linguistics
Semantic Notes
The term is exclusively anatomical and neurological. It is a compound noun where 'sacral' refers to the sacrum bone and 'plexus' denotes a network of nerves or vessels. It is never used metaphorically or in non-technical contexts.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Spelling and pronunciation follow standard national conventions.
Connotations
Purely technical and neutral in both varieties.
Frequency
Extremely low frequency in general language, used almost exclusively by medical professionals, anatomists, physiotherapists, and neurologists.
Vocabulary
Collocations
Grammar
Valency Patterns
The sacral plexus {verb}...Injury to the sacral plexus {verb}...Nerves {verb} from the sacral plexus.Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Not applicable.
Academic
Used in medical, anatomical, physiological, and surgical textbooks, research papers, and lectures.
Everyday
Virtually never used in everyday conversation.
Technical
Core terminology in neurology, neurosurgery, orthopaedics, anaesthesia (for nerve blocks), physiotherapy, and anatomy.
Examples
By Part of Speech
noun
British English
- The surgeon took great care to avoid the sacral plexus during the procedure.
- A detailed understanding of the sacral plexus is essential for diagnosing certain types of sciatica.
American English
- The MRI clearly showed a lesion affecting the sacral plexus.
- Anesthesia was administered via a fluoroscopically-guided sacral plexus block.
Examples
By CEFR Level
- The patient's leg weakness was traced back to a problem with the sacral plexus.
- Sacral plexus injuries, though rare, can result in significant sensorimotor deficits in the lower limbs and pelvic organs.
- The sciatic nerve, the body's largest, originates from the sacral plexus.
Learning
Memory Aids
Mnemonic
SACRAL PLEXUS: 'SACRum's ALlied PLEX of nerves for US in the lower body.' (SACRum + ALLied + PLEXus + US)
Conceptual Metaphor
The body as an electrical system: the plexus is a 'junction box' or 'network hub' where nerve cables converge and are redistributed to target areas.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'крестцовое сплетение' – this is the direct and correct translation. Ensure 'plexus' is not translated as 'плекс' (a false friend), but as 'сплетение'.
Common Mistakes
- Mispronouncing 'sacral' as /səˈkrɑːl/ or 'plexus' as /ˈplɛksjuːs/.
- Using it as a countable noun without 'the' (e.g., 'He has injured sacral plexus').
- Confusing it with the 'solar plexus' (coeliac plexus) in the abdomen.
Practice
Quiz
Which of the following is a primary function of the sacral plexus?
FAQ
Frequently Asked Questions
No. The sciatic nerve is the largest single nerve that emerges from the sacral plexus, but the plexus itself is the broader network from which several nerves, including the sciatic, originate.
Damage can result from trauma (e.g., pelvic fractures, surgery), compression (e.g., tumours, haematoma), radiation therapy, or medical conditions like diabetic neuropathy or inflammation.
Yes. Irritation, compression, or injury to the sacral plexus can cause pain, numbness, tingling, or weakness in the lower back, buttocks, legs, or feet, often in a non-dermatomal pattern.
It is a specialised regional anaesthesia technique where local anaesthetic is injected near the sacral plexus nerves, typically using ultrasound or fluoroscopic guidance, to provide pain relief for surgery or chronic pain conditions in its distribution area.