Table of ContentsView AllTable of ContentsAnatomyFunctionAssociated ConditionsTreatmentFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
Anatomy
Function
Associated Conditions
Treatment
Frequently Asked Questions
Your sacral vertebrae develop in the first and second months of embryonic development.
The first three vertebrae of the sacral region form the wide lateral wings called the alae. The alae (also called the ala or wing of sacrum) connect with the blades of pelvis—called theilium. The sacrum also forms the back wall of the pelvis and the joints at the hip bones called thesacroiliac joints.
There are a series of four openings on each side of the sacrum where the sacral nerves and blood vessels run. The sacral canal runs down the center of the sacrum, representing the end of the vertebral canal.
The five segments of the sacral vertebrae affect nerve communication to the lower part of the body. There, numerical levels are often mentioned in imaging studies of the spine. S1 refers to the first sacral bone, S2 to the second sacral bone, and so on. S1 is at the top and S5 is towards the bottom. Each number corresponds with the nerves in that part of the spinal cord.
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The function of the sacral vertebrae is to secure the pelvic girdle, the basin-like bone structure connecting the truck and the legs, supporting and balancing the trunk, and containing the intestines, bladder, bowel, and internal sex organs. Injuries to this area can affect bowel and bladder control, as well as sexual function, especially in men. Injuries to the sacral vertebrae are complex, often misdiagnosed, and not always appropriately treated.
Common causes of injuries related to the sacral vertebrae include car accidents, sports injuries, trauma, falls, birth defects, osteoporosis, and joint degeneration.
Injuries and damage to S1, S2, S3, S4, or S5 can still leave a person functional, but they primarily affect bowel and bladder function.
Most people with sacral vertebrae injuries tend to live very normal lives. They may need some assistance but can still do well on their own.
A person’s sacral vertebrae are generally healthy and rarelyfractured, except in the case of serious injuries, such as traumas to the area, including falls and blunt force.
Stress Fractures
People who haveosteoporosisorrheumatoid arthritis(RA) are predisposed to stress fractures in the sacrum.Stress fractures, also called hairline fractures, can be described as small cracks or slivers in the bone.
They mostly affect weight-bearing joints. They are less common in the femur, pelvis, or sacrum, but they are common in people with osteoporosis, RA and other rheumatic conditions because of theinflammatory processand reduced bone strength.
Stress Fracture Overview
Sciatica
Sciatica,a condition that causes back or leg pain, can arise from injury to the area where thelumbar spine(lower back, where the spine curves inward toward the abdomen) and sacral vertebrae connect. This is because this area of the spine is subject to huge amounts of stress and twisting from activity, such as sitting for long periods or playing a sport.
Sacral Nerve Injuries
While there are no spinal cord sections in the sacral vertebrae, the sacral nerves originate in the lumbar spine. Any damage to these nerve roots may cause similar symptoms to those ofspinal cord damage.
People with sacral nerve injuries will have symptoms on one or both sides of their bodies. Injuries to the sacral vertebrae may cause loss of function in the hips and/or legs, which affects activities, including walking and driving. Sacral vertebrae injuries may also cause bladder and bowel control dysfunction. However, injuries of the sacral vertebrae aren’t significant enough to affect daily living and self-care.
Symptoms of injuries to the sacral nerve roots may include:
Cauda Equina Syndrome
The cauda equina is a bundle of spinal nerves and spinal nerve rootlets of the second through fifth lumbar vertebrae, the first through fifth sacral nerves, and the coccygeal nerve of the tailbone. Cauda equina syndrome, a rare disorder where something compresses on the spinal nerve roots, usually affects vertebral levels L5 through S1.
The condition is a surgical emergency and without fast treatment, there could be lasting damage that leads to incontinence (loss of bladder control) and permanent leg paralysis.
Symptoms of cauda equina syndrome include:
The symptoms of cauda equina syndrome require immediate medical attention. You should seek out emergency medical attention for one or more of the symptoms of this condition.
If you have cauda equina syndrome, you will need surgery to relieve pressure off of the nerves, and the best outcomes are with 48 hours of the start of symptoms.
Cauda Equina Syndrome Symptoms
There are treatments for sacral vertebrae injuries.
Sacral injuries can also affect the tailbone. This type of injury—calledcoccydynia—is likely to cause bruising, discoloration, or fracture of the tailbone.
Home treatment of sacral and tailbone injuries might be all a person needs. However, if these fractures are severe or affect nerves, surgery might be necessary. It is important to remember that bones heal best when a person takes good care of themselves in a variety of helpful ways, including eating right and not smoking.
Frequently Asked QuestionsThere are five lumbar vertebrae. These make up the lumbar spine, which is located in the lower back above the sacrum.The sacral region is located at the end of the spine in the pelvic area. It is made up of five sacral vertebrae bones, which fuse together during adulthood to form a single bone called the sacrum.
There are five lumbar vertebrae. These make up the lumbar spine, which is located in the lower back above the sacrum.
The sacral region is located at the end of the spine in the pelvic area. It is made up of five sacral vertebrae bones, which fuse together during adulthood to form a single bone called the sacrum.
How to Relieve Tailbone Pain
5 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Okumura M, Ishikawa A, Aoyama T, et al.Cartilage formation in the pelvic skeleton during the embryonic and early-fetal period.PLoS One.2017 Apr 6;12(4):e0173852. doi:10.1371/journal.pone.0173852Degmetich S, Bailey JF, Liebenberg E, et al.Neural innervation patterns in the sacral vertebral body.Eur Spine J.2016 Jun; 25(6): 1932–1938. doi:10.1007/s00586-015-4037-4Lyders EM, Whitlow CT, Baker MD, et al.Imaging and treatment of sacral insufficiency fractures.American Journal of Neuroradiology. February 2010;31 (2) 201-210. doi:10.3174/ajnr.A1666Cleveland Clinic.Stress Fractures.Berg EJ, Ashurst JV.Anatomy, back, cauda equina.Additional ReadingAmerican Association of Neurological Surgeons. Anatomy of the Spine and Peripheral Nervous System.https://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Anatomy-of-the-Spine-and-Peripheral-Nervous-System. (n.d.)Medline Plus.Tailbone trauma – aftercare.
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Okumura M, Ishikawa A, Aoyama T, et al.Cartilage formation in the pelvic skeleton during the embryonic and early-fetal period.PLoS One.2017 Apr 6;12(4):e0173852. doi:10.1371/journal.pone.0173852Degmetich S, Bailey JF, Liebenberg E, et al.Neural innervation patterns in the sacral vertebral body.Eur Spine J.2016 Jun; 25(6): 1932–1938. doi:10.1007/s00586-015-4037-4Lyders EM, Whitlow CT, Baker MD, et al.Imaging and treatment of sacral insufficiency fractures.American Journal of Neuroradiology. February 2010;31 (2) 201-210. doi:10.3174/ajnr.A1666Cleveland Clinic.Stress Fractures.Berg EJ, Ashurst JV.Anatomy, back, cauda equina.Additional ReadingAmerican Association of Neurological Surgeons. Anatomy of the Spine and Peripheral Nervous System.https://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Anatomy-of-the-Spine-and-Peripheral-Nervous-System. (n.d.)Medline Plus.Tailbone trauma – aftercare.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Okumura M, Ishikawa A, Aoyama T, et al.Cartilage formation in the pelvic skeleton during the embryonic and early-fetal period.PLoS One.2017 Apr 6;12(4):e0173852. doi:10.1371/journal.pone.0173852Degmetich S, Bailey JF, Liebenberg E, et al.Neural innervation patterns in the sacral vertebral body.Eur Spine J.2016 Jun; 25(6): 1932–1938. doi:10.1007/s00586-015-4037-4Lyders EM, Whitlow CT, Baker MD, et al.Imaging and treatment of sacral insufficiency fractures.American Journal of Neuroradiology. February 2010;31 (2) 201-210. doi:10.3174/ajnr.A1666Cleveland Clinic.Stress Fractures.Berg EJ, Ashurst JV.Anatomy, back, cauda equina.
Okumura M, Ishikawa A, Aoyama T, et al.Cartilage formation in the pelvic skeleton during the embryonic and early-fetal period.PLoS One.2017 Apr 6;12(4):e0173852. doi:10.1371/journal.pone.0173852
Degmetich S, Bailey JF, Liebenberg E, et al.Neural innervation patterns in the sacral vertebral body.Eur Spine J.2016 Jun; 25(6): 1932–1938. doi:10.1007/s00586-015-4037-4
Lyders EM, Whitlow CT, Baker MD, et al.Imaging and treatment of sacral insufficiency fractures.American Journal of Neuroradiology. February 2010;31 (2) 201-210. doi:10.3174/ajnr.A1666
Cleveland Clinic.Stress Fractures.
Berg EJ, Ashurst JV.Anatomy, back, cauda equina.
American Association of Neurological Surgeons. Anatomy of the Spine and Peripheral Nervous System.https://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Anatomy-of-the-Spine-and-Peripheral-Nervous-System. (n.d.)Medline Plus.Tailbone trauma – aftercare.
American Association of Neurological Surgeons. Anatomy of the Spine and Peripheral Nervous System.https://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Anatomy-of-the-Spine-and-Peripheral-Nervous-System. (n.d.)
Medline Plus.Tailbone trauma – aftercare.
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