As a pain specialist doctor, I have come across many instances of pain over the tailbone, also known as coccydynia. Coccygodynia is fairly common and arises when the affected person sits, but also can be triggered when they try to stand up from a sitting position. Most cases resolves within a few weeks or months, but in a few individuals, coccygodynia can become a chronic condition that can be difficult to manage.
Anatomy and Function of the Tailbone
The coccyx or the tailbone is triangular and is at the end of the spine. It comprises 3 – 5 segments that form a single bone, but the first and second segments may not be fused. The coccyx is connected to the sacrum at S5, and is the attachment site for muscles and ligaments, helping to provide control for bowel opening during defecation, as well as support for the pelvic floor. The coccyx and the ischial tuberosities (another bony structure) help to provide postural support to a person when they are sitting down. Leaning backwards in a seated position increases the pain and pressure and stress on the coccyx and can be excruciating in someone with coccygodynia.
There are 4 types of coccyx
- Type I: Coccyx is curved forward, with its apex positioned downward.
- Type II: Coccyx has an exaggerated forward curvature, with the apex positioned in a straight forward
- Type III: The coccyx is angulated forward sharply
- Type IV: The coccyx is subluxed at the sacrococcygeal or intercoccygeal joint
Risk factors for Coccygodynia – Tailbone pain
- Obesity: Patients with a high BMI have an increased pressure in the pelvis when sitting, with an increased risk of backward movement of the coccyx which increases pressure and pain
- Rapid weight loss: Patients who lose weight rapidly also lose the cushioning around the coccyx and their coccyx is at risk of forward movement which can also increase pressure and pain
- Females: Females are 5 times as likely to have tailbone pain which may be a result of increased pressure in the pelvis and over the coccyx during pregnancy and delivery.
- Adults and adolescents are more likely have coccygodynia than children.
What causes it?
- Difficult childbirth
- Use of assistive devices during delivery
- Degenerative disc disease
- Hyper or Hypo – mobile sacrococcygeal joint
- Type 2/3/4 coccyx
- Abnormal muscle tone of the pelvic floor muscles that can cause spasms
What are the symptoms?
- Pain over the coccyx that feels like “pulling” or “cutting”
- Patients will need to sit on one buttock with the other buttock lifted off to take weight off the coccyx
- Pain is worse on prolonged sitting or when changing position from sitting to standing
- Pain is better when sitting on legs (japanese style)
- Pain when passing motion, coughing, and during menstruation
- Pain during sexual intercourse in females
Do patients with coccygodynia need an X-ray?
Patients with pain for over 8 weeks should consider an X-ray. The X-ray should include dynamic views when sitting and standing up so that the movement of the coccyx can be compared to ascertain its mobility.
How do you treat coccygodynia?
A period of conservative treatment with physiotherapy, massage and medications can be tried first, after which the pain specialist doctor may suggest some injections and other pain interventions that are done while you are asleep with some sedation. Pain interventions should be considered before the condition becomes too chronic and hard to treat. Open surgery may be required as a last resort but is not guaranteed to resolve the pain of coccygodynia.
- Modified wedge-shaped cushions (coccygeal cushions)
- Proper sitting posture
- Heat and cold treatment
- Nonsteroidal antiinflammatory drugs (NSAIDs)
- Topical creams
- Pain interventions
- Injections around the coccyx, usually at the sacrococcygeal junction or around the sacrococcygeal ligaments
- Caudal epidural steroid injections
- Ganglion impar injection and radiofrequency- targets the pelvic portion of the sympathetic trunk that transmits the pain signal
- Spinal cord stimulation of the sacral segment
- Open surgery
- Resection of the coccyx (coccygectomy)
- Injection of cement to the coccyx (coccygoplasty)
Injection done at the sacrococcygeal junction under X- ray guidance