To the Editor: We thank Harris and Buchbinder for their focus on interventional pain procedures.1 However, their description of the procedure they discuss has not been standard practice in pain medicine in Australia for many years.
They misrepresent the Medicare Benefits Schedule (MBS) number 39013 to solely include facet joint injections, whereas it includes local anaesthetic medial branch blocks, which are an evidence-based diagnostic test for posterior elements as a source of spinal pain, and can be therapeutic in their own right.2
The number needed to treat (NNT) is the number of patients that need to be treated for one to benefit compared with a placebo or sham in a clinical trial. The ideal NNT is one. After a positive medial branch block response, radiofrequency medial branch neurotomies — a procedure with an NNT ranging from two patients3 to 4.4 patients4 treated for one patient to receive effective relief of spinal pain — creates a “therapeutic window” in which ongoing spinal rehabilitation can occur.
From the 35 000 MBS number 39013 procedures performed in 2012, we can infer that fewer than 0.5% of Australians with spinal pain have facet joint injections and medial branch blocks in a 12-month period.
Contrary to the comments of Harris and Buchbinder, lumbar transforaminal epidural steroid injections are effective for the treatment of radicular pain associated with disc protrusion, with an NNT of 2.7,5 and in conjunction with active pain strategies may forestall spinal surgery.
Before impeaching facet joint injections and medial branch blocks, and thereby medial branch neurotomies, as well as lumbar transforaminal epidural steroid injections, Harris and Buchbinder should consider:
interprofessional patient-centred approaches are key;
pharmacological management is often ineffective;
their view does not reflect the current practice of Australian pain medicine physicians;
these procedures help people struggling to continue in social roles and maintain quality of life, so they help to reduce the economic impact of spinal pain on Australian society.
We support education to improve evidence-based practice of interventional procedures.
- 1. Harris IA, Buchbinder R. Time to reconsider steroid injections in the spine? Med J Aust 2013; 199: 237. <MJA full text>
- 2. Sehgal N, Dunbar EE, Shah RV, et al. Systematic review of diagnostic utility of facet (zygapophysial) joint injections in chronic spinal pain: an update. Pain Physician 2007; 10: 213-228.
- 3. Lord SM, Barnsley L, Wallis BJ, et al. Percutaneous radio-frequency neurotomy for chronic cervical zygapophyseal-joint pain. N Engl J Med 1996; 335: 1721-1726.
- 4. van Kleef M, Barendse GA, Kessels A, et al. Randomized trial of radiofrequency lumbar facet denervation for chronic low back pain. Spine 1999; 24: 1937-1942.
- 5. Vad VB, Bhat AL, Lutz GE, et al. Transforaminal epidural steroid injections in lumbosacral radiculopathy: a prospective randomized study. Spine 2002; 27: 11-15.
We acknowledge Andrew Briggs, John Quintner, Nicholas Cooke and Helen Slater for their assistance with this letter.
All authors work in public pain medicine units and perform interventional pain procedures. Stephanie Davies has a private fee-for-service practice; Stephanie Davies and Malcolm Hogg are board members of the Australian Pain Society, which has a position statement on interventional pain management procedures published in March 2010.