Postoperative cement augmentation after 360-degree fixation for highly unstable vertebral fractures in patients with multiple myeloma: a technical note on delayed trans-instrumentation vertebroplasty.

Abstract

Although surgical fixation is usually not part of the first-line treatment of spinal lesions in patients with multiple myeloma, there are some unique clinical situations (such as the presence of acute onset of neurological deficits) in which spinal decompression and instrumentation may be required. In such scenario, because of the presence of poor bone quality, the strength of the spinal construct is of paramount importance. Although several studies have demonstrated the benefits of cement augmentation in increasing the pullout strength of pedicle screw fixation, the injection of cement during placement of pedicle screws may hamper the possibility of additional circumferential screw fixation. In addition, cement injection into vertebral bodies full of tumor and in the presence of adjacent epidural disease may incur in higher risks of tumor extravasation and worsening of neurological deficits than cement injection after initiation of adjuvant therapies. The advantages of delayed trans-instrumentation vertebroplasty after 360-degree fixation are discussed in this technical note with an illustrative case of a patient with multiple myeloma presenting with cauda equina syndrome after a T12 compression fracture. In spite of the associated challenges of such an interventional procedure due to the presence of extensive hardware, carrying out delayed trans-instrumentation vertebroplasty after 360-degree circumferential fixations is not only feasible, but in our opinion, may constitute the best strategy to optimize the strength of spinal instrumentation in challenging scenarios involving poor bone quality, such as in patients with multiple myeloma.