Arthroscopic-assisted uni-portal non-coaxial endoscopic surgery for recurrent osteoid osteoma of the femoral neck: A case report.

rationaleOsteoid osteoma (OO) is a benign bone tumor predominantly affecting children and adolescents, commonly occurring in the diaphysis of long bones. Traditional open surgery causes damage to surrounding tissues, while radiofrequency ablation requires multiple fluoroscopic sessions, both of which may subject patients to unnecessary harm. However, when OO involves special anatomical structures such as the femoral neck, the difficulty of treatment is further increased. Arthroscopic-assisted uni-portal non-coaxial endoscopic surgery (AUNES), as a novel minimally invasive technique, integrates the advantages of both arthroscopic and endoscopic technologies. It enables precise lesion resection while minimizing tissue damage to the greatest extent. Therefore, this article explores the application value of this technique in femoral neck OO through recurrent cases. PATIENT CONCERNS: A 10-year-old female presented with recurrent right thigh pain 11 months after initial open resection of femoral OO, characterized by nocturnal pain responsive to nonsteroidal anti-inflammatory drugs but with no signs of inflammation. DIAGNOSES: Imaging studies confirmed recurrent OO at the right femoral neck.

interventionsThe patient underwent AUNES with single-portal tumor resection and allogeneic bone grafting under arthroscopic guidance. OUTCOMES: Complete pain resolution was achieved with no recurrence at 1-month follow-up. The technique demonstrated advantages including minimal incision (4 cm), low radiation exposure and early functional recovery. LESSONS: AUNES is a promising treatment for recurrent femoral neck OO, particularly in pediatric patients. While this case shows excellent short-term outcomes, long-term follow-up and larger studies are needed to validate efficacy.