Instability and impending instability in patients with vertebral metastatic disease

Abstract

Metastatic disease commonly involves the spine with an increasing incidence due to a worldwide rise of cancer incidence and a longer survival of patients with osseous metastases. Metastases compromise the mechanical integrity of the vertebra and make it susceptible to fracture. Patients with pathological vertebral fracture often become symptomatic, with mechanical pain generally due to intervertebral instability, and may develop spinal cord compression and neurological deficits. Advances in imaging, radiotherapy, as well as in spinal surgery techniques, have allowed the evolution from conventional palliative external beam radiotherapy to modern stereotactic radiosurgery and from traditional open surgery to less-invasive, and sometimes prophylactic stabilization surgical treatments. It is therefore clear that fracture risk prediction, and maintenance or restoration of intervertebral stability, are important objectives in the management of these patients. Correlation between imaging findings and clinical manifestations is crucial, and a common knowledge base for treatment team members rather than a compartmentalized view is very important. This article reviews the literature on the imaging and clinical diagnosis of intervertebral instability and impending instability in the setting of spine metastatic disease, including the spinal instability neoplastic score, which is a reliable tool for diagnosing unstable or potentially unstable metastatic spinal lesions, and on the different elements considered for treatment.

Treatment Strategy for Impending Instability in Spinal Metastases

“… 13 14 15 16) However, it is difficult to determine whether a surgical intervention is indicated for the intermediate category (scores 7–12, impending instability), which has been discussed in only a few studies. 17 18) …”

Mechanical Cavity Creation with Curettage and Vacuum Suction (Q-VAC) in Lytic Vertebral Body Lesions with Posterior Wall Dehiscence and Epidural Mass before Cement Augmentation

“…In patients with neoplastic lytic vertebral lesions, reducing pain, stabilizing fractures or lesions at risk of fracture, and ultimately improving quality of life are key elements of treatment. VA, with its technical variants, has an established role in achieving these goals [1,2,5]. However, not all procedures are applicable to extensive lytic lesions.…”

“…Percutaneous vertebral augmentation (VA) with vertebroplasty (PVP), balloon kyphoplasty (BKP), or vertebral body stenting (VBS) is often performed in patients with painful, fractured, or at-risk-of-fracture neoplastic spinal lytic lesions. The main goals are reinforcement of the vertebral body, stabilization or prevention of a fracture, and pain relief [1,2,3,4,5,6]. However, complication rate of VA, including cement pulmonary embolism and epidural cement leakage, is higher in patients with neoplastic when compared with osteoporotic fractures [7,8].…”

Vertebral fractures following stereotactic body radiotherapy for spine metastases

“…30 SINS is generated by calculating scores from one clinical and five radiographic parameters; relating to the spinal level of the lesion; the presence of mechanical or nonmechanical pain; whether the lesion is lytic, sclerotic or a combination of both; the presence of spinal malalignment or deformities; the extent of vertebral body collapse; and the involvement of posterolateral spinal elements. 49 SINS >6 was shown to be associated with elevated VCF rates, placing patients in the potentially unstable/mechanically unstable categories. 30 Within SINS, lytic vertebral lesions, pre-existing VCF and spinal malalignment were identified on multivariable analyses across multiple studies as independent risk factors for VCF.…”