Multifragmentary Thoracic Fracture as an Initial Sign of Solitary Bone Plasmacytoma: Trauma-Oncologic Approach in a Mexican Patient.

Although multifragmentary thoracic fractures are usually associated with high-energy trauma, they may also be the initial manifestation of an underlying neoplasm. Although infrequent, Solitary Bone Plasmacytoma (SBP) can present with severe vertebral collapse even after minimal trauma, highlighting the importance of considering oncological aetiologies in patients with atypical vertebral pain or slow progression. We present the case of a 48-year-old Mexican patient with a multifragmentary T7 fracture secondary to dorsal trauma, which was initially managed conservatively. The appearance of progressive neurological deficit and structural instability prompted advanced imaging studies. Magnetic resonance imaging (MRI) revealed 90% collapse of the T7 vertebral body with retropulsion of the posterior wall, and positron emission tomography/computed tomography (PET/CT) showed focal hypermetabolic uptake at T7/T8 compatible with a tumour lesion and spinal cord compression. Decompression was performed via laminectomy and transpedicular fixation, with resection of the abnormal tissue for histopathological and immunohistochemical analysis. The study confirmed SBP with a CD38⁺ immunophenotype and restriction to lambda light chains. Multidisciplinary management included surgery, fractionated radiotherapy (45 Gy), zoledronic acid, lenalidomide, and denosumab. The patient experienced favourable clinical evolution and partial neurological recovery (strength 5/5 in the lower limbs and no residual sensory deficit).