Ablative therapy for Osteoid Osteoma
Osteoid osteoma (OO), a benign bone tumor, constitutes around 2-3% of primary bone tumors. Despite its small size, it frequently leads to patient discomfort and complaints. It is characterized by persistent and intense pain, often worsening at night, causing sleep disruption and functional limitations. This adversely affects daily activities and overall quality of life. Surgical removal has been the primary treatment, but in recent years, percutaneous ablation techniques like radiofrequency ablation (RFA) have emerged as a safe and effective alternative. RFA offers low complication and recurrence rates, reducing hospitalization costs and duration.
Keypoints:
| Symptom | 1. Localized bone pain (prostaglandin mediated)- worsen at night, relieved by aspirin and NSAIDS 2. Bone deformity 3. Growth disturbance 4. Joint capsule OO cause joint swelling, synovitis, and restricted mobility |
| Bones involved | 1. Most common- Femur and tibia. 2. Other common sites include the spine, hands, and feet. 3. OO can occur in any bone |
| Role of Medical management | 1. OO may be self-limiting but may take years (2-6) to regress 2. Medical management using NSAIDS may not be feasible for long term in patients with refractory pain, sleep deprivation or those who could not tolerate long-term NSAIDs therapy. |
| Other treatment options | 1. Surgical resection 2. CT guided Radiofrequency ablation 3. CT guided percutaneous resection 4. Laser ablation - for lesion < 8 mm from vital structure |
| Anesthesia | 1. General 2. Spinal 3. Propofol induced |
| RF electrode placement | 1. The cannula with stylet is advanced through the soft tissues to the bone surface (remove inner stylet to avoid metal artifact) 2. Tip directed toward the center of the nidus 2. Check CT to confirm tip positioning prior to ablation. |
| Clinical success | 1. The lesion is generally heated to 90°C for a time of 5-6 minutes (optimal ablation parameters). 2. Absence of pain for 2 years |
| Post-procedure | 1. Stressful weight bearing and prolonged strenuous activity should be avoided for 1–3 months 2. Except for driving, other activities can be resumed after discharge |
| Contraindications | 1. Location of a lesion - hand, spine (<1 cm from vital structures such as nerves) 2. Pregnancy 3. Cellulitis 4. Sepsis 5. Deranged coagulation profile |
| Complications | 1. Skin burn 2. Nerve Injury (avoid by keeping electrode 1 cm away from the nerve) 3. Bleeding 4. Infection |