Absent Hypoplastic Coccyx C1856644
A congenital condition where the tailbone is absent or underdeveloped. Typically identified in newborns. Most cases are mild and may not require treatment.
Key facts at a glance
- ICD-10
- Q84.9
- ICD-11
- LA00.0
- Body system
- congenital
- Severity
- mild
- Chronic
- true
Signs and symptoms
Common signs and symptoms that may indicate this condition.
Generalized symptoms
(congenital)Mild symptoms that may not significantly impact daily life.
Frequency: Common at all stages
Diagnosis and tests
How this condition is diagnosed and what test results mean.
Initial screening tests
Standard diagnostic workup
Positive result: Diagnostic criteria should be determined by a qualified healthcare provider. [Content pending medical review.]
Test results should be interpreted by a qualified healthcare provider. [Content pending medical review.]
Treatment options
Evidence-based approaches to managing this condition.
First-line treatments
Cushioned seating and positioning
Using specially designed cushions and ergonomic seating to reduce pressure on the coccygeal area and improve comfort during sitting activities.
Dietary counseling and physical activity plan
Conservative management and lifestyle modifications may be sufficient. Monitor symptoms.
Pelvic floor and core strengthening
Targeted physical therapy to strengthen pelvic floor muscles and core stability, which can compensate for reduced structural support from the absent coccyx.
Additional treatment options
Pain management as needed
For patients experiencing discomfort, appropriate pain management approaches including topical treatments and systemic medications as prescribed by a healthcare provider.
medicationImaging for comprehensive assessment
If not previously done, imaging studies may be recommended to fully characterize the anatomical variation and rule out associated conditions.
procedureGentle manual therapies
Gentle massage and soft tissue work to the surrounding pelvic and gluteal regions may help manage associated discomfort and improve function.
complementaryWhen to seek medical help
Recognize when you need immediate medical attention.
Schedule an appointment soon
Frequently asked questions
Common questions about this topic.
What is Absent Hypoplastic Coccyx C1856644?
Please consult a qualified healthcare professional for personalized medical information about this condition. [Content pending medical review.]
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Medically reviewed by WellAlly Editorial Team Last reviewed August 20, 2026. · Read our editorial policy