Twenty-Five-Year Failure of Spinal Allograft Incorporation in Chronic Spinal Hydatid Disease: A Case Report

Spinal allografts are commonly used in vertebral reconstruction to provide structural support and facilitate fusion, particularly in cases involving extensive bone loss. Although graft nonunion and failure are recognized complications, these events are typically identified within the early or mid-term postoperative period. The long-term results of spinal allografts over decades remain poorly documented.

A 45-year-old woman with a 25-year history of disseminated hydatid disease who underwent lumbar hemivertebrectomy, cyst excision, posterior instrumentation, and bone allografting came to the emergency department with new symptoms. Despite prolonged cyclic albendazole therapy, she developed repeated lumbosacral and gluteal recurrences complicated by chronic secondary infections. Over time, progressive vertebral destruction, persistent drainage, and irreversible neurological deficits were seen, leaving the patient bedbound. Cultures during recurrent infections grew Streptococcus mitis/oralis and Finegoldia magna. More than 2 decades after the initial surgery, the patient presented to the emergency department with an open lumbar wound and extrusion of bone-like material, which was found to be the spinal allograft. The patient was managed with local wound care, antimicrobial therapy, and supportive treatment.

This case shows that a spinal allograft can remain completely nonincorporated for decades in a severely compromised vertebral environment. Chronic cystic echinococcosis with secondary infection prevented graft revascularization, leaving the allograft biologically inert and resulting in very late extrusion. This unprecedented outcome underscores that long-term allograft behavior depends primarily on sustained biological conditions rather than surgical technique or initial stability.