A 14-year-old male was admitted to our clinic for treatment of extremely severe spinal deformity associated with progressive late-onset paraplegia. His medical history included the diagnosis of intramedullary astrocytoma at the age of 3 years in another hospital, where he underwent posterior total laminectomy through the thoracic spine (from T4 to T8), with tumor excision performed without fusion. Intramedullary astrocytoma represents 29% of pediatric spinal cord tumors in the literature.
He reported that kyphosis deformity began to appear 1 year after posterior laminectomy. Later, he underwent posterior spinal fusion without any instrumentation at 9 years of age. However, the deformity gradually progressed over the years. Seven months before admission to our hospital, the patient began to feel lack of strength and sensation in lower extremities bilaterally, with no complains regarding bladder or bowel dysfunction. No improvement in spinal cord function was achieved with conservative measures, and the patient gradually lost the ability to walk and required a wheelchair for movement (Fig. 1). The patient and his family denied any recent or remote history of trauma, tuberculosis, or any other infections. The family history was unremarkable; meanwhile, the patient exhibited signs of serious psychosocial problems since he had to use a wheelchair in daily life.
The patient's preoperative coronal and sagittal thoracic kyphosis Cobb's angles were 70  and 170 , respectively (Fig. 2). Preoperative whole spine three-dimensional-computed tomography (3-D CT) scans showed extremely severe postlaminectomy thoracic kyphotic deformity; with the apex at T6 vertebra and previous spinal fusion (Fig. 3); magnetic resonance imaging (MRI) of the spinal canal revealed spinal cord compression at the apex of the kyphosis (Fig. 4). There was no neurological abnormality such as split cord malformation or tethered cord. The electrodiagnostic investigation demonstrated neurological deficit. Pulmonary function tests (PFTs) revealed forced vital capacity (FVC) and forced expiratory volume for 1 second (FEV1) of 31.8% and 33.8%, respectively. Cardiac Doppler ultrasonographic investigation demonstrated mitral and tricuspid regurgitation, with no anomalies of other visceral organs.
Physical examination showed skin hypoesthesia below the T6 level and lower limb spasticity. The patient had weakness of the intrinsic musculature of lower limbs, with left and right lower extremity Grade 3/5 and Grade 1/5 motor strength in all muscle groups, respectively. His Achilles and knee tendons showed hyperreflexia, and the Babinski sign was positive. The overall spinal cord function was classified as Frankel C.
In 2014, the patient underwent preoperative assessment by a team of pediatrics, neurosurgery, anesthesiology, and respiratory specialists, and diagnosis of postlaminectomy rotokyphoscoliosis associated with late-onset paraplegia and severe pulmonary ventilation disorder were confirmed based on the findings. The patient was suggested a revision surgical treatment, and the single stage posterior-only VCR procedure was scheduled. In brief, pedicle screws were inserted using the free-hand technique based on previous studies. The patient underwent a VCR at T6 for spinal cord decompression, deformity correction, and posterior spinal fusion from T2 to L3 (Fig. 5). The autograft and allograft were used for posterior final spine fusion. During the operation, motor evoked potential (MEP), somatosensory evoked potential (SEP), and wake up test were performed to assess intraoperative complications of spinal cord injury.
The operation time was 450 minutes, and blood loss was 1500 mL. Intraoperatively, a dural tear was noted and repaired; MEP and SEP signals were lost during the entire operation, and the wake-up test was positive. Postoperatively, the patient was transferred to the intensive care unit (ICU) and required positive pressure ventilation support to improve his respiratory condition. On postoperative day 2, he was extubated and transferred to the orthopedic ward, where he received neurotrophic medicines and rehabilitation exercises. The patient required a chest tube for postoperative pleural effusion. The child experienced unplanned return to the operating room for cerebrospinal fluid leak (CSF) on postoperative day 18. The plastic thoracolumbosacral orthosis braces were preserved for 6 months after revision operation.
The spinal cord function improved gradually after the posterior-only VCR procedure. At 3 months, left and right intrinsic musculature of lower limbs both exhibited Grade 3/5 motor strength in all muscle groups. Left and right intrinsic musculature of lower limbs recovered to Grade 4/5 motor strength at 12 months postoperatively. At 18 months postsurgery (follow-up visit), intrinsic musculature of lower limbs displayed Grade 5/5 motor strength, and sensation in lower extremities bilaterally had returned to normal, with the neurological status improving from preoperative Frankel C to Frankel E. At the 24-month follow-up, the good spinal cord function was maintained. Long-standing scoliosis radiographs demonstrated that the major curve at coronal plane was improved to 20  immediately after surgery and 21  (correction rate, 70%) at final follow-up; the thoracic sagittal kyphosis curve was improved to 76  immediately after surgery and 75  (correction rate, 55.9%) at the final follow-up (Fig. 6). PFTs revealed FVC and FEV1 of 40.5% and 43.5%, respectively. Postoperative clinical photographs showed overt improvement (Fig. 7).