Delayed arachnoid ossification following lumbar decompression and fusion surgery: A case report and review of literature.

RATIONALE: Lumbar Decompression and Fusion Surgery is an effective and safe surgical technique widely used for treating spondylolisthesis. Arachnoid ossification (AO) is a rare condition associated with neurological dysfunction after lumbar spine surgery, with limited reports in the literature. In this report, we present a rare case of AO detected 1 year after lumbar fusion, with serial imaging first revealing its emergence and guiding early detection and intervention.

PATIENT CONCERNS: A 61-year-old female who experienced progressive pain and numbness in both lower extremities 2 years after undergoing lumbar decompression and fusion surgery.

DIAGNOSES: Based on the medical history, symptoms and imaging studies, the patient was diagnosed with Delayed AO.

INTERVENTIONS: After discussing the condition and evaluating surgical options, a conservative treatment regimen was implemented, including nonsteroidal anti-inflammatory drugs (NSAIDs) for analgesia and anti-inflammatory effects, methylcobalamin for neurotrophic support, mannitol combined with corticosteroids to reduce neuroinflammatory edema, and adjunctive acupuncture therapy.

OUTCOMES: There was a partial relief of symptoms including pain and numbness in both lower limbs on the 7th day after systemic treatment. These symptoms had improved by the 12th day; however, mild pain and discomfort persisted in the right foot. Following symptom alleviation, the patient was discharged from the hospital.

LESSONS: Patients may experience pain and numbness in both lower limbs after lumbar decompression and fusion surgery. This condition is likely attributed to the compression of spinal nerves caused by AO within the spinal canal. Given the significant surgical risks associated with this procedure, a systematic conservative treatment approach is recommended, which can yield satisfactory therapeutic outcomes.