16
Chronic Back Pain, Failed Surgery, and What to Do When All Options Are Exhausted
Lawrence G. Lenke
■ Introduction
Despite the recognition of spine surgery as a unique discipline combining the best of orthopedic surgery and neurosurgery, spine surgery does not portend a perfect result for many patients. The rate of revision spine surgery is difficult to quantify, but it is not unusual for a busy spine surgery center to have many more patients undergoing surgery as a revision than as a primary. In all fairness to the spine surgery profession, even with successful spine surgery, at certain levels adjacent-segment pathology from progressive degeneration unrelated to the prior surgical procedure(s) can ensue at some point postoperatively, which may require further operative intervention. The term failed back surgery syndrome (FBSS) has been coined to depict a patient who has either not benefited from a spinal surgical procedure or who has had complications that led to a less than favorable outcome.1–3 This chapter discusses the difficulty of managing patients who have chronic back pain or have failed spine surgery. How should these patients be evaluated, and what are the remaining treatment options? When would a potential surgical solution be advisable? FBSS patients are an important group to analyze to provide future guidance on not only the management but also the avoidance of this situation for future spine surgery patients. Also, the economic impact of caring for these patients long-term is not inconsequential and has negative impact on the spine surgery profession.4
■ Patient Management
For the chronic back pain patient, the key is to identify the pain generator. For most patients who have seen appropriate spine care physicians, the pain generator is an enigma. For patients who have a demonstrable pain generator, such as a large bulging disk, an inflamed sacroiliac joint, or a severely arthritic facet joint, various nonoperative treatments will provide at least partial relief. When a pain generator cannot be identified, then surgery should definitely not be offered, which should be a logical conclusion. A more difficult scenario is when there is a defined pain generator, such as a degenerated bulging disk, but confirming the physiological connection between the pathology and the pain is difficult. Because of the known common occurrence of spinal degenerative pathology and aging, and the inconsistent correlation with degenerative pathology seen on imaging and correlative symptoms, surgeons need to be very careful when offering surgery to patients with these common degenerative pathologies and chronic back pain.5,6
The workup of patients with chronic back pain to determine if surgery is indicated includes standard imaging such as plain upright radiographs, lumbar magnetic resonance imaging (MRI), and computed tomography (CT) scans. A technetium bone scan can highlight areas of increased metabolic uptake, with a potential correlation with pain generators that can be ameliorated by surgery. Diskography has fallen out of common practice due to the potentially deleterious effects of the annular puncture and nucleus disruption. Ultimately, the onus is on the spinal surgeon to sort out the merits of whether further surgery would be indicated and provide a good outcome. If the answer is no, which is usually the case, then the surgeon needs to provide the patient with other nonoperative options for managing the symptoms. Most spine centers are working with nonoperative specialists coming from disciplines such as pain management, physiatry, physical therapy, chiropractic medicine, and acupuncture, among others, and these practitioners should be consulted to provide additional diagnostic and potential therapeutic options to the patient.7
For patients with prior surgery, the list of potential pain generators expands dramatically. The workup of these patients begins by taking a thorough history beginning with the reason for the initial operation. For those who have had multiple spinal surgeries, the details regarding the indications for each procedure need to be delineated, if possible, along with the specific procedure(s) performed. Next, the chief complaint at the current time along with the time sequence of this problem needs to be determined. Unfortunately, with multiple spinal surgical procedures that have not helped the patient’s symptoms, there are always psychological and emotional undertones that complicate the ability to determine if there is a structural or mechanical issue that can be resolved by additional surgery. Also, many of these patients are being co-managed by a pain management team, with resultant narcotic dependence that further complicates the ability of a spinal surgeon to sort out whether further surgery will be beneficial, even if there are obvious radiographic abnormalities that could be managed surgically. Thus, the evaluating spinal surgeon needs to be aware of all of these physical, psychological, and emotional overlays that contribute to the overall patient presentation.
Despite the multitude of negative implications of a multiply operated patient when contemplating additional surgery, there are distinct diagnoses that can benefit from additional surgery. These include obvious pseudarthrosis, especially when loose or misplaced instrumentation is confirmed, or when there is an obvious progression of altered spinal alignment from a segmental, regional, or global perspective. The optimal way to determine these conditions is with the evaluation of upright anteroposterior (AP) and lateral radiographs of the involved region of the spine. Occasionally comparing the upright radiographs to supine or prone radiographs will highlight an obvious area of pseudarthrosis by demonstrating a change in spinal alignment when gravity is removed from the upright posture. Obviously, when there is broken instrumentation, with a change in alignment from previous radiographs, spinal instability is then confirmed, and restoring stability and alignment can lead to a good result. This type of analysis is always important to do for patients presenting with long spinal instrumented constructs extending to the sacrum or pelvis, as these constructs are notorious for developing problems, especially at the bottom of the construct, where the stress and strain on the bony elements are tremendous. That region of the spine is also often best evaluated with a corresponding CT scan assessing the sacrum and pelvis. A sagittal CT reconstruction can highlight loose screws, L5-S1 pseudarthrosis, intradiskal pathology, and even sacral stress fractures (Fig. 16.1).
