By Ron Feise, DC
IN THE UNITED STATES, SPINAL SURGERY rates over the last few decades have risen dramatically. Between 1993 and 2008, cervical fusion surgery increased 625.8 percent, and lumbar fusion surgery increased 773.6 percent.1-3 These increases accelerated when fusion cages were approved, but artificial disc replacement has not demonstrated a clinical superiority over fusion.4-7 The most common primary diagnosis for cervical and lumbar fusion is degenerative disc disease.8,9 Yet, as explained below, degenerative disc disease is not a pathologic process automatically necessitating treatment.
Spinal surgical procedures are expensive. Between 2001 and 2010, an estimated 3.6 million spinal fusions were performed in the United States accounting for more than $287 billion in total hospital charges, excluding charges associated with readmissions, rehabilitation, prescription drugs, professional fees or indirect costs associated with loss of productivity.9-11 Make no mistake; spinal surgery is big business. But is it good for patients and the U.S. healthcare system?
Double the Rates of Other Countries
The United States has the highest rate of cervical and lumbar spine surgery in the world. The spinal surgical rate in the United States is roughly twice that in New Zealand, Australia, Canada, Norway and Finland, and it is more than triple the United Kingdom’s rate.3,12,13 There is no reason to believe that there are biological differences from country to country, and epidemiological studies suggest that rates of back pain are similar among geographic areas.14,15 Compared with other developed countries, the surgical rates in the United States may be explainable: fee-for-service and easy access to care are thought to encourage spinal surgery in the United States.
Factors Behind the U.S. Surge in Spinal Surgery
• Irrelevant Imaging Findings Drive Surgery
Degenerative changes and disc herniation of the spine are biological realities, but pain and disability do not necessarily accompany these conditions. A major problem with imaging is that it can reveal issues that are alarming but irrelevant. An international research team found no evidence demonstrating that disc degeneration is a risk factor for neck pain.16 The American College of Physicians and the American Pain Society reached a similar conclusion for back conditions.17
A systematic review estimated the prevalence by age of common degenerative spine conditions on imaging in asymptomatic individuals.18 Thirty-three articles reporting imaging findings for 3,110 asymptomatic individuals revealed that about 30 percent of 20-year-olds and more than 80 percent of 80-year-olds have disc degeneration or bulge without any symptoms. This study found that imaging findings of degenerative changes, such as disc degeneration, disc bulge and disc protrusion, are generally part of the normal aging process rather than pathologic processes requiring intervention. These findings have been affirmed by numerous medical research teams for both neck and back conditions.19-39 Perhaps most important, the relationship between imaging findings and surgical outcomes has not been established.40,41
Recent scientific research has found that herniated discs can be resolved after conservative treatment or even after no treatment.42 The probability of low-back herniated disc regression without surgical treatment but after conservative treatment, such as spinal manipulation, exercise, physical therapy or NSAIDS, is 70 percent for disc extrusion and 41 percent for disc protrusion. According to medical research, active conservative treatment produces a satisfactory outcome even for patients with obviously extruded discs or marked neurological deficits.43-46
● Serious Adverse Events Ignored
Serious adverse events caused by spinal surgery are remarkably common. Several published studies conducted by independent medical research teams found that the reoperation rate (i.e., failure rate) for spinal surgery is greater than 22 percent.47-52 Serious postoperative pain and disability were experienced by more than 29 percent of patients following total lumbar disc replacement.53,54 Death rates following spinal surgery are about 5 per 1,000 operations,9,55-57 and blindness following spinal surgery is estimated at more than 1 per 1,000 operations.58-60 Despite these serious and catastrophic occurrences, it is well known that spinal surgeons routinely underreport adverse events.61
● Surgery for Non-Serious Symptoms
You would think that risky spinal surgery is reserved for serious cases with high levels of pain and high levels of dysfunction. Unfortunately, it is not. Many of the research subjects undergoing surgery have only mild to moderate pain and dysfunction,62-71 and many have never been screened for depression, anxiety or catastrophizing.72-81 Yet, many of these patients have these psychological co-morbidities, which amplify pain and dysfunction and thereby increase the probability that the pain condition will persist over an extended period of time.82-103 Many spinal surgical clinical trials do not even require a minimum amount of pain intensity or dysfunction before surgery is administered. Among trials that include pain intensity or dysfunction inclusion criteria, most establish very low entry requirements.49,104-114 This promotes the use of surgical procedures in patients with non-serious symptoms who are better suited for nonsurgical approaches.
● Misleading Informed Consent
The International Society for Study of the Lumbar Spine has developed a research-based informed consent sheet for spinal surgery outlining the odds of occurrence for various complications, with appropriate emphasis on “serious or frequently occurring risks.”115 The document is a good first step, but it is incomplete, because it fails to provide risks and benefits for alternatives to surgery, fails to include a crucial summary statistic — the probability that at least one of the listed adverse events will occur (the risk is 30 percent) — and omits some serious adverse events, such as the risks of death and blindness. In most cases, patients should consider spinal surgery optional, and they should have information to assess the risks and benefits of their treatment alternatives. Shockingly, most spinal surgeons do not even provide the industry-established informed consent to their patients. [Editor’s Note: Informed consent documents by law do not have to report the risks and benefits of alternatives to the therapy being offered, only that alternatives exist.]
• Spinal Surgeons Resist Placebo Trials
Randomized, double-blind, placebo-controlled trials are the gold standard for evaluating interventions and are routinely used to assess medical therapies.116,117 But spinal surgeons have been reluctant to use imitation surgery as a placebo control in the evaluation of spinal surgery.118,119 It is well-known that even an ineffective surgery can carry a larger placebo effect than nonsurgical treatments.120-124 So the question remains: Could the supposed benefits attributable to spinal surgery just be placebo? [Editor’s note: Placebo surgeries are ethically difficult to do and few have been done in the modern era.]
● Medicare and all insurance companies should refuse all payments for cases that have a diagnosis associated with disc herniation/degeneration and/or spinal arthritis.
● State medical boards, medical societies and insurance companies should require that all potential surgery patients receive a written informed consent that outlines all possible adverse events, similar to the document from the International Society for Study of the Lumbar Spine. The document should be revised to include a summary adverse event statistic, as well as the risks and benefits for alternative strategies.
● All patients should be required to be screened (and treated, as necessary) by a psychologist for depression, anxiety and catastrophizing. All patients (i.e., especially patients with mild to moderate pain/dysfunction) should be treated for 12 to 24 months with nonsurgical interventions, such as spinal manipulation, physical therapy and spinal rehabilitation, before considering surgery.
● Qualified researchers from both surgical and nonsurgical camps should conduct at least two quality randomized, double-blind, placebo-controlled trials to assess the efficacy of spinal surgery.
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