Paraspinal extramedullary hematopoiesis masquerading as nerve sheath tumor.

Paraspinal tumors are uncommon tumors involving the soft-tissue around the vertebrae. The lesion could originate from nerve roots, soft tissue, or blood vessels. The diversity of the lesions poses diagnostic dilemma, warranting robust histopathological diagnosis. We report such a case presenting with radicular pain due to paraspinal extramedullary hematopoiesis (EMH) masquerading as nerve sheath tumor. EMH is presence of hematopoietic tissue outside the bone marrow. EMH is usually seen as a compensatory mechanism associated with underlying hematological disorder. Our case presented primarily as paraspinal mass without underlying hematological disorder on evaluation. Thus, recognizing that EMH can present as paraspinal mass even without a diagnosis of pre-existing hematological disorder is crucial.

Distal Junctional Failure Secondary to Nontraumatic Fracture of Lower Instrumented Vertebra: Our Experience and Review of Literature.

BACKGROUND: Junctional kyphosis (JK) is usually observed in long-level instrumented fusion surgeries. Various contributing factors are proposed, the pre-existing and postoperative spinal imbalance is considered as the single most important factor for the development of JK in adult spinal deformity surgeries. Distal JK (DJK) is seldom reported compared to proximal JK (PJK), and scarce literature exists. METHODS: We report 2 unique cases of distal junctional failure (DJF) with worsening of neurology, secondary to nontraumatic fracture of a lower instrumented vertebra operated for thoracic canal stenosis without deformity. The first case had acute worsening of the Neurology during follow up and on evaluation, the supine CT and MRI scan revealed well decompressed spinal canal, no implant migration to the canal, no screw loosening, or rod failure. Supine sitting radiographs demonstrated DJK with Fracture and the patient underwent extension of fusion till the pelvis with 3-rod construct and interbody fusion, because of the instability at the L1 level.The second case remained neurologically stable for a month and then had an acute onset of back pain, sensory deficit, and urine incontinence. The supine-sitting dynamic radiograph done demonstrated L1 fracture with DJK at D12-L1 levels. The patient was counseled for extension of fusion, which was deferred by the patient. RESULTS: Patients in our series, had an acute worsening of neurological deficit within a month of posterior spinal fixation. Their supine imaging was almost normal, and the diagnosis of DJK with L1 fracture instability was possible only on a supine-sitting dynamic radiograph. Various factors like obesity, TL kyphosis, osteoporosis, etc. can be the attributing factors for the development of DJK CONCLUSION: A high index of suspicion is required for diagnosing nontraumatic fracture in long-level fusion patients with acute neurological worsening. The supine-sitting dynamic radiograph is an important diagnostic tool for DJF in patients having difficulty standing erect. LEVEL OF EVIDENCE: 4. CLINICAL RELEVANCE: Application of sitting and supine dynamic radiographs to diagnose instability in patients unable to stand for flexion and extension radiographs.