Proximal junctional failure combined with symptomatic thoracic disc herniation: a rare case report.

Abstract

To report a complex case of proximal junctional failure (PJF) associated with acute thoracic disc herniation (TDH) in the mid-thoracic spine following thoracolumbar fusion. Case report. A 74-year-old female with osteoporosis and rheumatoid arthritis underwent multiple spinal fusion and revision surgeries, culminating in a T9-S1 fusion. Two months following the third revision, she developed PJF. Seven months following the third revision, she presented with severe pain and progressive sensory loss in both lower extremities (predominantly left side). Neurological examination revealed incomplete paraparesis (AIS grade C). While initial cervical MRI findings were unremarkable, thoracic imaging demonstrated a T8 vertebral fracture and a significant T8/9 disc herniation causing spinal stenosis. The patient underwent T5-S1 revision surgery, including T8 laminectomy and sequestrectomy. Seven months after the fourth revision surgery, her neurological function improved significantly to AIS grade E, with significant pain relief. PJF may precipitate acute intervertebral disc herniation due to excessive biomechanical stress at the adjacent mobile segment. Early restoration of sagittal alignment and proactive spinal stabilization are crucial for protecting spinal cord function.