Long-term follow-up of conservatively treated popliteal cysts in children.

This study was undertaken to determine the long-term outcome of conservatively treated popliteal cysts in children. It was based on a review of 20 cysts, none of which were initially treated surgically. The records of children with popliteal cysts between 1986 and 1992 were studied, and a group of patients without other diseases or other physical abnormality in the knee region was selected. Twenty-one patients were included and were subjected to a clinical and ultrasound investigation. Three were lost to follow-up, leaving 18 patients with 20 cysts available for analysis. In the follow-up period, which ranged from 5 to 10 years, 14 cysts were treated conservatively with a mean follow-up of 7 years, whereas 6 cysts were operated on after a mean period of 2 years. Of the conservatively treated cysts, eight had disappeared and six had shrunk. Although spontaneous remission is not to be expected in all cases, asymptomatic popliteal cysts in children can be treated conservatively with good results.