J Orthop Surg (Hong Kong). 2008 Apr;16(1):27-9. Dextrose prolotherapy for recalcitrant coccygodynia.

Khan SA, Kumar A, Varshney MK, Trikha V, Yadav CS. Department of Orthopaedics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India. shahalamkhan@rediffmail.com Comment in: J Orthop Surg (Hong Kong). 2008 Aug;16(2):270; author reply 270.

Abstract
PURPOSE: To present the results of dextrose prolotherapy undertaken for chronic non-responding coccygodynia in 37 patients.
METHODS: 14 men and 23 women (mean age, 36 years) with chronic coccygodynia not responding to conservative treatment for more than 6 months were included. 27 of them had received local steroid injections. A visual analogue score (VAS) was recorded for all patients before and after injection of 8 ml of 25% dextrose and 2 ml of 2% lignocaine into the coccyx. In 8 patients with a VAS of more than 4 after the second injection, a third injection was given 4 weeks later.
RESULTS: The mean VAS before prolotherapy was 8.5. It was 3.4 after the first injection and 2.5 after the second injection. Minimal or no improvement was noted in 7 patients; the remaining 30 patients had good pain relief.
CONCLUSION: Dextrose prolotherapy is an effective treatment option in patients with chronic, recalcitrant coccygodynia and should be used before undergoing coccygectomy. Randomised studies are needed to compare prolotherapy with local steroid injections or coccygectomies