Sonographic evaluation and diagnosis of postoperative pseudotumor of the back with histologic correlation

Trauma to the back with ligamentous injury may, rarely, result in the development of a fibrocartilaginous mass and can be clinically mistaken for a neoplastic process. Only a few cases of posttraumatic pseudotumor of the back have been reported in the literature (n = 14), and all of these have involved the nuchal ligament in the cervical spine. We report a case of pseudotumor of the back involving the posterior interspinous ligament overlying the 12th thoracic vertebral body evaluated with sonography and definitively diagnosed with sonographically guided biopsy.