[Sacro-coccygeal cyst: surgical techniques and results]

69 patients with a chronic inflamed pilonidal sinus were reviewed. They were operated either with a deep excision to sacrum (37 patients) or with the Lord Millar technique (32 patients). 66 patients (87%) were controlled at a mean follow-up of 3.7 years after the operation. The socio-economical advantage of the Lord Millar operation is demonstrated by the shorter hospital stay (4.9 vs 7.6 days) and the shorter period of disability (14 vs 26 days). 5 recurrent episodes were observed among the 31 patients followed-up after an excision (16%) and 7 among the 29 followed-up after a Lord Millar operation (24%). In the later group one recurrence was seen in the sub-group of the 16 patients regularly epilated after the operation (6%) and 6 in the sub-group of the 13 who were not controlled (46%). We conclude that the Lord Millar operation is an alternative to the deep excision operation provided the patients is motivated enough to come regularly to the control for an epilation.