A rare case of misdiagnosis: Sacrococcygeal osteoid osteoma that was treated surgically as a pilonidal sinus in a pediatric patient

Abstract

Background. We report a misdagnosed pediatric case of osteoid osteoma in sacrococcygeal region. Previously it was said by general surgery that the source of pain was the pilonidal sinus and was therefore operated. A CT scan was taken and showed that the patient had sacrococcygeal osteoid osteoma which nidus was very close the right S4 spinal root. The lesion was therefore marked on CT scans and resected by performing an open surgery. Methods. This report reviewed the patient's medical records, imaging studies, treatment, and related literature. Results. Our patient, who had a continuous pain for 2 years, applied to our orthopedic clinic due to aches and pain at sacrococcygeal region. The characteristic clinical symptom was nocturnal pain especially night that decreases or resolves completely with salicylates. Previously it was said by general surgery that the source of pain was the pilonidal sinus and was therefore operated. Our patient who had no decrease pain after surgery was advised to use salicylate which resulted in dramatic responses. A CT scan was taken and showed that our patient had sacrococcygeal osteoid osteoma which nidus was very close the right S4 spinal root. The lesion was therefore marked on CT scans and resected by performing a mini-open surgery. Conclusion. Osteoid osteoma is a benign tumor of bone, especially in children and young adults. Often seen in the lower bones of the lower extremity, the sacral vertebra is very rare and causes severe localized pain at night. When such a chart is encountered in children and young adults, osteoid osteoma should be considered carefully in the differential diagnosis.