Background and aims In general, the indication of the ganglion impar block is considered to be the anal pain and the perineal pain. We experienced accidentally that the ganglion impar block performed for anal pain was effective for the pain caused by pubic bone metastasis. Furthermore, we used this block for the pain caused by pubic bone metastasis and it was effective.

Methods The ganglion impar block was performed for 4 cancer patients, all with cancer pain caused by pubic bone metastasis. The ganglion impar block with 3 ml of 1%mepivacaine was performed at first. After successful good effects with local analgesic were obtain, neurolytic block were performed, by two times of radiofrequency thermocoagulation (at 90 degrees Celsius for 180 seconds) and injection of 3 ml of absolute alcohol.

Results All were female cancer patients from 58- to 72-years-old. In three patients, NRS pain score was decreased, from mean NRS of 9.3(9/10–10/10) to mean NRS of 1.6(0/10–3/10). One patient obtained analgesic effect, which was reduced the frequency for rescue dosage, from five times per day to one time per day.

Conclusions The ganglion impar block may provide a good analgesic effect on pain caused by the pubic bone metastasis.