What causes coccydynia?

Causes of Coccydynia

The most common causes of coccydynia (tailbone pain) are trauma, abnormal mobility of the coccyx, and degenerative changes, with trauma being the primary cause in most cases. 1

Primary Causes

Traumatic Causes

• Direct trauma is the most frequent cause, including falls directly onto the tailbone, childbirth, and prolonged sitting on hard or narrow surfaces 1, 2
• Fracture, subluxation, or luxation of the coccyx can occur during traumatic events, particularly during childbirth in women 3
• Intrapartum coccygeal fractures can lead to postpartum coccydynia that may become chronically symptomatic if not properly diagnosed and treated 3

Abnormal Mobility

• Hypermobility of the coccyx is the most common pathological finding in patients with coccydynia, present in approximately 70% of cases 1
• Anterior and posterior subluxation or luxation of the coccyx can occur during sitting and standing, detectable on dynamic radiographs 1, 2
• Chronic static and dynamic overload from activities such as prolonged sitting, bicycling, rowing, and riding can contribute to abnormal coccygeal mobility 1

Degenerative Changes

• Disc degeneration at sacrococcygeal and intercoccygeal segments can lead to coccydynia 1
• Coccygeal spicules (bony excrescences) can form and cause pain, particularly during sitting 1, 2
• Patients with spicule formation may be good candidates for surgical intervention if conservative treatment fails 2

Secondary Causes

Extracoccygeal Disorders

• Pilonidal cyst, perianal abscess, and hemorrhoids can present with symptoms mimicking coccydynia 1
• Diseases of pelvic organs can refer pain to the coccygeal region 1
• Disorders of the lumbosacral spine, sacroiliac joints, piriformis muscle, and sacrum may manifest as coccygeal pain 1

Other Factors

• Obesity is associated with increased risk of developing coccydynia due to increased pressure on the coccyx during sitting 4
• Female gender is a risk factor, possibly due to anatomical differences in the pelvis 4
• Osteomyelitis and tumors, though rare, can cause coccygeal pain 1

Idiopathic Coccydynia

• In approximately 30% of patients with coccydynia, no specific cause can be identified 1
• These cases are classified as idiopathic coccydynia and may respond differently to treatment approaches 1

Clinical Implications

• Proper diagnosis of the underlying cause is essential for effective treatment planning 5, 4
• Conservative treatment is successful in 90% of cases, with many resolving without medical intervention 4
• Surgical intervention (coccygectomy) should be reserved for refractory cases, particularly those with evidence of advanced coccygeal instability or spicule formation 2
• Patients should be warned about the high rate of infection (27%) following surgical intervention 5

Understanding the specific cause of coccydynia in each patient allows for targeted treatment approaches, improving outcomes and reducing the need for invasive interventions.