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Metastases are the neoplasms most commonly seen by both orthopaedic and neurosurgeons, and the spine is the site most frequently involved (,). At autopsy, more than 70% of patients who die of cancer have vertebral metastases (). Although nearly all malignancies may metastasize to bone, carcinoma of breast and bronchogenic origin, lymphoma, and multiple myeloma account for half of all spinal metastases (,,,,,,).

Surgical resection, reconstruction, and internal fixation of the spine are often indicated in the management of patients with lumbosacral neoplasms. Because of the complex anatomy of this region, aggressive resections are technically demanding and often involve long operative times and significant blood loss. Some wide resections may require the purposeful sacrifice of nerve roots, with inherent functional consequences for the patient. In addition, the unique biomechanical features of the lumbosacral junction, combined with the destructive nature of neoplastic processes and the resection of such disease, present a challenging problem in terms of spinal reconstruction and stabilization. The purpose of this chapter is to review the important anatomic, biomechanical, and functional considerations of this region; to provide a step-by-step description of techniques for the resection of lumbosacral tumors; and to describe current methods of spinopelvic reconstruction and stabilization. Although the differential diagnosis of lumbosacral lesions is broad and includes inflammatory conditions as well as a variety of developmental abnormalities and cysts, the discussion here is limited to the management of neoplastic disease.

Spine tumors can be classified by their relation to the spinal canal and its coverings. Tumors can arise from the different tissue types around the spinal column, such as neural tissue, meningeal tissue, bone, and cartilage. Furthermore, distant primary tumors can metastasize to the spine by hematogenous or lymphatic routes. Both benign and malignant tumors may occur in either location and at any level of the spine.

Approximately 50 to 70% of all cancer patients ultimately develop skeletal metastases, and the spine is the most common site of metastatic deposition. Most patients with spinal metastases are treated nonsurgically, commonly with radiation therapy, chemotherapy, radiopharmaceutical therapy, hormonal therapy, and antiresorptive therapy with bisphosphonates and analgesics (,). Usually, surgery is considered only for patients with intractable pain, neurological compromise, and overt or impending instability. The goals of spinal tumor surgery are to decompress the spinal cord and nerve roots, stabilize the spine, alleviate pain, and, in some cases, establish a diagnosis. Occasionally, the goal of surgery for a patient with a primary neoplasm of the spine is to effect a cure.

Metastatic tumors to the spine account for significant morbidity in cancer patients. With treatment, one seeks to restore quality of life, reduce pain, and preserve or maintain neurological function. The roles for chemotherapy, radiation therapy (RT), and surgery continue to evolve, but clearly all play significant roles in treating metastatic spinal tumors. Initial attempts to treat tumors using a laminectomy approach proved no better than radiation alone. Inherently, laminectomy is ineffective for treating metastatic spine tumors because it does not effectively address anterior vertebral body or epidural tumor, and creates iatrogenic instability. The evolution of operative approaches for metastatic spine tumors, including anterior transcavitary and posterolateral, and the development of segmental fixation has markedly improved surgical outcomes (–, –, –). This chapter describes the authors’ indications, operative techniques, and outcomes using a singlestage posterolateral transpedicle approach (PTA) (), which provides exposure for epidural tumor and vertebral body resection, and anterior and posterior reconstruction.

Primary bone tumors are rare, accounting for approx 0.4% of all tumors, and primary spine tumors represent only approx 10% of all bone tumors (,). Overall, primary spine tumors are much less common than metastatic lesions to the spine. The nature of a primary bone tumor of the spine depends largely on the location of the lesion and the age of the patient. Lesions located within the vertebral body are far more likely to represent a malignancy, particularly a metastatic lesion, than lesions in the posterior elements. Up to 75% of tumors located within the vertebral body are malignant, compared with only 35% found in the posterior elements (). Metastatic lesions involve the vertebral body initially in approx 85% of cases, and are seven times more likely to involve the vertebral body than the posterior elements.

The primary goal of treatment for patients with malignant primary spine tumors is to provide cure, or the best chance of cure, if possible. If cure is not possible, we seek to palliate pain and provide early return to function and activity, to maintain or improve neurological function, and to provide a stable spinal column. The “upside” to an aggressive resection of a primary spinal malignancy has never been higher, making the “downside” to a poorly planned or executed surgery all the more unacceptable. With improved medical and radiotherapies, the treating physician now has the opportunity—and the obligation—to carefully tailor treatment to the biology and stage of each specific spine tumor (Table 1). The role of surgery differs depending on tumor type, stage, and location.

Complications related to the treatment of spinal neoplasms are often associated with inaccurate pre-operative assessment and diagnosis, as well as the definitive surgical procedure. A careful history and physical examination can lead to the appropriate diagnosis () and identify co-existing premorbid conditions, which may require further evaluation before operative intervention. Appropriate radiological and laboratory studies are important because they may lead to the correct diagnosis and direct proper treatment (). In general, once a lesion is identified, a biopsy should be obtained to make a definitive diagnosis. Exact techniques of the biopsy and the definitive treatment should be tailored to the nature and location of the lesion and the patient’s general condition and life expectancy. A multidisciplinary team approach consisting of surgical, medical, and radiation oncologists, combined with experienced radiologists and pathologists, helps optimize patient care. The goals of operative intervention of spinal tumors are pain control, maintenance, or improvement of neurological function, eradication of the tumor, and maintenance of spinal stability, and the attainment of normal coronal and sagittal alignment.

The literature regarding the use of braces in patients with spinal tumors is sparse. In fact, most references on spinal bracing relate to (1) idiopathic adolescent scoliosis (–), (2) osteoporotic compression fractures (–, and (3) thoracolumbar spine fractures (–). The role of bracing is much less well defined for the operative and non-operative treatment of spinal tumors. However, they are commonly used in the immediate postoperative period after tumor resection and surgical stabilization to protect both the patient and the integrity of the spinal construct. Although long-term bracing may be successfully used as the sole way of treating spinal instability resulting from tumor, the role of long-term bracing for patients with spinal tumors appears limited. In this setting, with or without the additional use of neoadjuvant chemo- and radiation therapy, biological capacity to achieve spinal fusion may be limited or absent. High pseudoarthrosis rates should, therefore, be expected. If life expectancy is limited to less than 6 mo, braces are frequently applied in one form or another for the purpose of palliation, particularly if surgical treatment is not contemplated or feasible, but spinal instability is of concern.

Rehabilitation is a critical part of the interdisciplinary approach to treating cancer patients suffering from tumors of the spinal column. Early mobilization and physical therapy (PT) intervention play and important role in preventing complications ( Fig. 1) () and improving quality of life. Rehabilitation is an integral part of the spine oncology team. It includes physical therapy, occupational therapy (OT), nursing, social work, case management, and physicians. This chapter discusses the role of PT and OT in patients with spinal tumors.