Vertebroplasty: Clinical Experience - Current Concepts and Outlook

Clinical Experience

Clinical decision-making regarding the use of vertebroplasty has typically involved a multidisciplinary team with input from a radiologist, orthopedic surgeon, neurosurgeon, and (in the cases of tumors) an oncologist and radiation specialist. Most procedures to date have been performed by neuroradiologists, with some orthopedists and neurosurgeons gaining experience recently.

Indications for the procedure vary according to the underlying diagnosis. General contraindications include uncorrectable coagulation disorders (because a large diameter needle is used), and absence of a back-up orthopedic or neurosurgical team for emergent spinal decompression of cement leakage. Poor pulmonary status and difficulty lying prone are relative contraindications. Other considerations are specific to the condition being treated.

Vertebral Hemangioma

The earliest cases of percutaneous vertebroplasty were for painful hemangioma of the vertebral body, refractory to medical treatment. When radiographs show aggressive hemangioma and there is pain but no neurologic signs, vertebroplasty is combined with an injection of alcohol into the contralateral part of the vertebra, to sclerose the hemangioma. When neurologic signs are present, especially when an epidural mass is responsible, vertebroplasty has been combined with same-day injection of N-butyl cyanoacrylate to thrombose the hemangioma followed by next-day surgical laminectomy, hemangioma resection from the epidural space, and fusion.¹⁸ Small numbers of patients have been treated in each of these categories, with no complications reported.^{7, 8} In particular, 11 of 12 patients with vertebroplasty and alcohol injection for radiographically aggressive hemangioma had lasting pain relief.⁷

Spinal Tumors

Tumors of the spinal column most frequently involve the anterior elements, effect an older population, and represent metastatic lesions. Treatment options for these patients may be limited by co-morbid medical conditions, primary tumor burden elsewhere in the body, and nutritional deficiency; these factors may make vertebrectomy and strut graft fusion through an anterior approach unreasonably risky. Yet some treatment is still needed to offer pain relief from pathologic fractures, and to achieve stabilization of weakened vertebrae to prevent deformity from further collapse. Radiation is a mainstay of treatment, but may have only a partial effect, and the onset of pain relief is typically delayed by 2 weeks.

In this context, percutaneous vertebroplasty has been used for treatment of patients with painful, collapsing vertebrae due to metastatic cancer or myeloma. It may suffice as an alternative to a large anterior procedure and offer adequate pain relief and stability. It may be combined with radiation or chemotherapy or both, and it is an attractive option for recurrent metastatic focus when the radiation limit for the field has been reached. Specific indications include painful fracture refractory to the medical management, and worsening collapse of a vertebral body.⁶ Multifocal metastatic disease, in which vertebrectomy would not be curative, is a particularly appropriate indication.

Relative contraindications include loss of vertebral body height >60-65%,⁶ though this is debated and may change as basic science investigation offers possibilities such as the inflatable bone tamp. Soft tissue extension of the vertebral metastasis, and cortical defects, especially of the posterior body wall, are also relative contraindications.⁹

Good results have been reported in several series.^6-9 Two series^{6, 7} have treated and followed 101 and 44 patients, with marked pain relief in 80% and 73% of cases, respectively. In the latter study, the pain relief and spinal stabilization persisted at an average follow-up of 7.1 months. The results in cases of vertebroplasty without accompanying radiation indicated that vertebroplasty is an effective as radiation, and in some ways more versatile.⁶