A patient presents with coccydynia, having recently lost weight while taking weight loss medication, and reports soreness in the tailbone area when sitting or lying down, possibly due to perceived loss of gluteus maximus muscle mass, what are the next steps in management?

Management of Coccydynia Following Weight Loss

For this patient with coccydynia related to recent weight loss and reduced gluteal cushioning, initiate conservative management with a specialized coccyx cushion, NSAIDs, and pelvic floor physical therapy, while obtaining dynamic sitting/standing lateral radiographs to assess for coccygeal hypermobility or morphologic abnormalities. 1, 2

Initial Diagnostic Evaluation

The first step is obtaining dynamic X-rays of the coccyx in both standing and sitting positions to evaluate morphologic parameters and hypermobility 1. This imaging approach is critical because:

• Hypermobility is defined as >25% posterior subluxation while sitting or >25° flexion while sitting 1
• Significant hypermobility is considered when posterior subluxation exceeds 35° 1
• Key radiographic features associated with coccydynia include Type II coccyx morphology, subluxation of the intercoccygeal joint, and presence of bony spicules 1

If plain radiographs are inconclusive but clinical suspicion remains high, advanced imaging with MRI or CT can reveal coccygeal pathology not visible on X-ray 3. This is particularly relevant when patients report mobile fragments or focal tenderness on palpation 3.

Physical Examination Findings

Document the following specific findings:

• Focal midline tenderness during direct palpation of the coccyx 2
• Pain located below the sacrum and above the anus 2
• Symptoms that worsen with sitting or during transitions from sitting to standing 2
• Assessment of weight loss magnitude and timeline, as rapid loss of >10% body weight can cause physiological changes 4

Conservative Management Algorithm (First-Line)

Conservative treatment is successful in 90% of coccydynia cases 5, and should include:

1. Mechanical Interventions

• Specialized coccyx cushions with a cutout or wedge design to reduce direct pressure on the tailbone 2, 5
• Ergonomic adaptations to minimize sitting time and pressure 5

2. Pharmacologic Management

Following a stepped-care approach for musculoskeletal pain 4:

• Start with acetaminophen or short-term tramadol as first-line agents 4
• If inadequate, progress to non-COX-2 selective NSAIDs at the lowest effective dose 4
• For patients with cardiovascular risk factors, consider adding low-dose aspirin 81 mg with a proton pump inhibitor 4

3. Physical Therapy

• Pelvic floor rehabilitation and manual manipulation/massage 5
• Physical therapy focusing on pelvic floor muscles, which insert on the coccyx 5

Interventional Management for Refractory Cases

If conservative measures fail after 8-12 weeks, consider escalation:

Injection Therapy

• Local steroid injections into the coccygeal region 2, 5
• Ganglion impar block for pain control 1

Advanced Interventional Procedures

• Ultrasound-guided radiofrequency ablation (RFA) of the coccygeal nerve combined with steroid injection shows significant improvement, with 54% of patients achieving >50% pain reduction at 12 weeks 6
• RFA is performed at 90°C for 60 seconds after lidocaine injection, followed by dexamethasone and bupivacaine 6
• This approach results in lower adverse event rates compared to other interventions 6

Additional Options

• Transcutaneous electrical nerve stimulation (TENS) 5
• Manual manipulation and massage 1, 5
• Extracorporeal shock wave therapy 1

Surgical Consideration

Coccygectomy should be reserved for rare cases refractory to all conservative and interventional treatments 2, 5. Surgical removal has a high success rate for pain reduction when appropriately selected 2, 3.

Critical Pitfalls to Avoid

• Do not overlook the coccygeal region on imaging studies - radiologists must be familiar with normal coccyx morphology and differential diagnoses in the sacrococcygeal region 1
• Avoid premature surgical intervention - 90% of cases resolve with conservative management 5
• Do not rely solely on static radiographs - dynamic sitting/standing views are essential to detect hypermobility 1
• Consider advanced imaging (MRI/CT) when clinical suspicion is high despite negative plain films 3

Weight Loss Context

While the patient attributes symptoms to gluteal muscle loss from weight loss medication, document the specific medication, total weight loss, and timeline 4. Rapid weight loss can cause multiple physiological changes, but the primary issue here is mechanical - reduced soft tissue cushioning increases direct pressure on the coccyx during sitting 2. This does not change the management algorithm but reinforces the importance of cushioning interventions.