By avoiding spinal instrumentation in pediatric patients: Surgical management of a lumbar aneurysmal bone cyst with preservation of spinal stability

Aneurysmal bone cysts (ABCs) are benign, expansive, and highly vascularized bone lesions that are uncommon in the spine, accounting for up to 10%–20% of all cases and predominantly affecting pediatric and adolescent patients 1 . Their progressive growth can lead to neurological compromise secondary to spinal cord or nerve root compression; therefore, timely surgical treatment is essential 3 .We present the case of a 13-year-old male patient with an unremarkable medical history, who presented with the spontaneous onset of paresthesias in the lower extremities during daily activities, followed by a progressive decline in sensitivity and muscle strength, which resulted in functional gait limitation. On neurological examination, inguinal, perineal, and genital hypoesthesia were remarkable, with no sphincter dysfunction. Complete resection of the lesion was performed, including an L3 and L4 laminectomy, without spinal instrumentation. Histopathological examination confirmed the diagnosis of an aneurysmal bone cyst. The decision to avoid lumbar instrumentation was based on the patient's pediatric age, the preservation of posterior biomechanical stability, and the goal of not interfering with vertebral growth. The placement of fixation systems in skeletally immature patients can alter normal spinal development, limit segmental mobility, and promote secondary deformities or accelerated degeneration of adjacent segments. Current evidence recommends reserving arthrodesis and instrumentation for cases with preexisting instability, extensive resections, or subsequent progressive deformities 5 .