Today’s Medical Journal of Australia (MJA Insight) has an interesting article on the increase in rates of spinal fusion surgery for chronic low back pain.
Spinal surgery has been on the rise in recent years and despite the lack of research to back the procedure’s effectiveness in resolving chronic pain. A recent Australian study on trends in spinal surgery has noted a significant increase in the rate of fusions. Over a 10-year period, numbers of spinal fusions had increased by 175% – from 8.4 per 100,000 to 23.1 per 100,000.
The decision to perform a fusion is often based on clinical examination and radiological imaging but these are unreliable guides to surgical or other pain interventions. Anxious patients with high expectations from modern surgical technology has led to growing enthusiasm for surgical fusions.
Experts are now calling for tighter guidelines – including a mandatory waiting period – before patients are able to undertake the procedure.
Dr Richard Williams, an orthopaedic surgeon and the spokesperson for the Royal Australasian College of Surgeons, told MJA InSight that a key requirement should be a waiting period of 12 months from consultation to surgery. During this time, the patient would undergo aggressive rehabilitation to try to lose weight and thereby reduce back pain.
Dr Williams says “most patients will recover after these 12 months” “It’s the duty of the doctor to set realistic expectations for the patient, and explain that spinal fusion rarely results in having no pain at all. The surgery works for a proportion of patients, not all.”
Today, chronic pain is understood in terms of a biopsychosocial concept although this can be difficult to explain to a patient. The anatomy of the pain has been likened to the inner core of an onion, with additional layers surrounding the core of a painful experience from the past such as childhood issues, masked depression, substance abuse, pain behaviour and entitlements to secondary gain. For the benefit of the patient and the reputation of the surgeon, these aspects of chronic pain need to be carefully explored before considering spinal surgery.
In the absence of a diagnosis, magnetic resonance imaging (or MRI) of the lumbar spine is required to exclude congenital or advanced pathological change. This tends to “open up a Pandora’s box” . Imaging will identify degenerative changes from the third decade onwards, including disc dehydration (the black disc), disc narrowing, lateral facet joint arthropathy and bone spurs. However, there is very little correlation between imaging findings of disc herniation and the clinical course. Imaging findings of structural change of osteoarthritis do not correlate with pain production. The patient with chronic low back pain, having seen the report of the radiologist and suggestions for further pain interventions, then has renewed expectations of successful treatment.
There is a growing tendency for the astute spinal surgeon to have all patients assessed independently and, at times, for them to attend an interdisciplinary pain programmes to clarify issues of psychological origin that might complicate recovery.
While the spinal fusion procedure remains controversial, it would be valuable for spinal surgeons to undertake a national audit of patient-centred outcomes for the procedure, similar to the excellent audit carried out for hip and knee arthroplasties by the Australian orthopaedic surgeons.
In the meantime, patients are probably best advised to proceed very cautiously to surgery.
