Malignant peripheral nerve sheath tumor of the sciatic nerve presenting with leg pain in the setting of lumbar scoliosis and spinal stenosis.

STUDY DESIGN: Case report. OBJECTIVE: We present a case of malignant peripheral nerve sheath tumor (MPNST) presenting as neuropathic pain in the setting of lumbar scoliosis and spinal stenosis. Most peripheral nerve sheath tumors are benign, and malignant cases are more commonly associated with neurofibromatosis type 1 or prior radiation exposure. MPNST is a rare tumor with a poor prognosis. We report a case of MPNST that presented as neuropathic pain following lumbar decompression and fusion surgery. METHODS: A 60-year-old woman presented for management of lumbar scoliosis, stenosis, and left leg pain. After lumbar decompression and fusion surgery, the patient was readmitted to the hospital after falling 10 weeks post-op. She reported gradual recurrence of leg pain. Left foot drop was noted on exam. Imaging studies showed no spinal changes postoperatively or residual stenosis. Obesity limited electrodiagnostic studies. Hip MRI revealed a lobular soft tissue mass in the left sciatic notch. Surgical resection and pathology provided the diagnosis of MPNST. The patient declined wide resection and other interventions after seeking a second opinion. Palliative pain management was implemented. RESULTS: The patient expired 15 months after her index spinal surgery. CONCLUSIONS: MPNST is an extremely rare tumor that can present with symptoms similar to radiculitis. Clinical signs and symptoms of MPNST are vague and nonspecific due to compression of surrounding structures. Surgical wide resection is the first line of treatment for MPNST with chemotherapy and radiotherapy as adjuvant treatments. MPNST has a poor prognosis with reported 5-year survival ranging from 16 to 54%. This case demonstrates the need to pursue additional workup when diagnostic imaging and objective findings do not satisfactorily explain the clinical presentation. LEVEL OF EVIDENCE: IV.

Acute Renal Infarction After Lateral Lumbar Interbody Spinal Fusion for Kyphoscoliosis.

STUDY DESIGN: Case report. OBJECTIVES: Case report of acute renal infarction following lateral interbody fusion with posterior instrumentation for adult lumbar kyphoscoliosis. SUMMARY OF BACKGROUND DATA: This is the first reported renal infarction following minimally invasive lateral interbody fusion and posterior spinal instrumentation. METHODS: We report a case of acute renal infarction in a 72-year-old woman following direct lateral interbody fusion (DLIF) with percutaneous pedicle screw and rod fixation from L1 to L5 for correction of kyphoscoliosis. She reported vague abdominal pain on postoperative day (POD) 7. Abdominal ultrasound findings revealed no abnormalities. The patient tolerated a regular diet, improved in rehabilitative modalities, and had stable vital signs. Abdominal computed tomographic (CT) scan on POD 9 for persistent abdominal pain revealed right renal infarction and right renal artery occlusion. The patient was transferred to the ICU for evaluation, where intravenous heparin was administered and no reperfusion was performed. Transesophageal echocardiography on POD 14 revealed moderate diffuse plaque in the descending aorta. RESULTS: Surgical correction of kyphoscoliosis through DLIF and posterior spinal instrumentation was performed with improvement of deformity. Subsequent acute renal infarction was noted. The patient was discharged home on POD 21. There were no further adverse events up to the 1-year follow-up. CONCLUSIONS: A lateral approach to the anterior lumbar spine may precipitate renal artery occlusion and renal infarction in patients with atherosclerosis. Diagnosis of renal infarction requires a high index of suspicion because the primary complaint may be vague back, flank, and abdominal pain. We emphasize the importance of recognizing potential symptoms early to prevent additional renal injury. Caution should be taken with deformities around the origin of the renal arteries and great vessels, especially in patients with atherosclerosis. LEVEL OF EVIDENCE: Level IV.