Distal femur osteosarcoma in a seven-year-old: a case report on acute symptom presentation.

Introduction and importance: Osteosarcoma is an exceptionally serious, uncommon disease in children with morbidity, mortality, and psychological burdens.

Case presentation: In this report, the authors present the case of a previously healthy 7-year-old girl who exhibited continuous, painful limping. Plain imaging and a MRI scan revealed the presence of a lytic lesion in the femur on the left side. The diagnosis of osteosarcoma was confirmed. There was no significant familial history of cancer. The girl and her family underwent the operation and chemotherapy, received follow-up and support for a year, and both the patient and the medical team expressed a lot of satisfaction.

Clinical discussion: The survival and prognosis from osteosarcoma in the literature was 59% for all patients at a median follow-up up 54 months, current treatment of osteosarcoma involves chemotherapy and limb surgery, with (60-80)% of patients in remission after 5 years.

Conclusion: This case emphasizes the importance of promptly considering osteosarcoma in a child when the clinical presentation and medical imaging align with the diagnosis.