Adnexal torsion is rare in children and is usually reported as small series or case reports. We reviewed a series of 19 consecutive cases of children aged 3 to 19 years (mean, 9.6 years) who were treated in our institution between 1977 and 1988. Thirteen patients presented with torsion of a previously normal adnexa, while six presented with torsion of a diseased adnexa. The right adnexa was involved in 84% of cases. Detorsion with recovery of vascularization of the adnexa was possible in only four cases. All patients presented with lower abdominal pain, and onset was sudden in 78% of cases with an average of 5.2 days between the first symptom and hospital admission and a mean delay of 30.2 hours between consultation and surgical intervention. A previous history of abdominal pain was present in nine cases. Nausea or vomiting were present in 84% of cases. An abdominal mass was palpable in 42% of the patients and was associated with a delay in surgical intervention. Ultrasound confirmed the presence of a mass in 94% of cases. The preoperative diagnosis was accurate in 37% of cases, and the most common inaccurate diagnosis was appendicitis or appendiceal abcess. Our series confirms the predominance of right-sided lesions as reported in the literature. It is not clear whether this is an anatomic phenomenon or whether the suspicion of appendicitis leads to the more frequent diagnosis of right-sided lesions, whereas many left-sided adnexal torsions are being missed. We therefore advocate pelvic ultrasound in female patients who present with left lower quadrant pain.(ABSTRACT TRUNCATED AT 250 WORDS)