Improvement in Pain Following Ganglion Impar Blocks and Radiofrequency Ablation in Coccygodynia Patients: A Systematic Review

Nearly 90% of cases of coccydynia can be managed with conservative medical treatment; the remaining 10% need other invasive modalities for pain relief, such as ganglion impar block (GIB) or radiofrequency ablation (RFA) of the ganglion impar. A systematic research was conducted of PubMed, MEDLINE, and Google Scholar to identify studies reporting pain relief in terms of visual analogue scale (VAS), or its counterparts, following GIB or RFA in coccydynia patients with the purpose to determine the efficacy of GIB and RFA of the ganglion impar in controlling pain in coccydynia patients. Seven studies were delineated, with a total of 189 patients (104 in GIB group and 85 in RFA group). In the GIB group, the mean VAS improved from 7.83 at baseline to 3.11 in the short-term follow-up, 3.55 in the intermediate-term follow-up, and 4.71 in the long-term follow-up. In the RFA group, the mean VAS improved from 6.92 at baseline to 4.25 in the short-term follow-up, and 4.04 in the long-term follow-up. In the GIB group, a 13.92% failure rate (11/79) and a 2.88% complication rate (3/104) were reported, while in the RFA group, a 14.08% failure rate (10/71) and no complications (0%) were reported. Total success rate was > 85% with either modality. Ganglion impar block and RFA of the ganglion impar are reliable and probably excellent methods of pain control in coccydynia patients not responding to conservative medical treatment. However, a demarcation between responders, non-responders, and late non-responders should be considered, and larger studies with a longer follow-up (> 1 year) are needed.