Cost-effectiveness of minimal interventional procedures for patients with chronic low back pain

In The Netherlands the majority of patients with low back pain is successfully
treated in primary care. Approximately 20% of the patients, however, still have
symptoms after 3 months and 5% after 1 year. In The Netherlands, costs of low
back pain are enormous: ¤ 3.4 billion in 2007 (Lambeek, van Mechelen et al.
2010). Patients with chronic low back pain are responsible for the majority of
the high costs.
Mechanical low back pain is defined as pain resulting from single sources:
facet, discus, sacroiliac joint or a combination of these. In the proposal we
use the terminology in this way.
When primary care treatment has not been successful in alleviating symptoms,
patients may be referred to medical specialists. Minimal interventional
procedures are commonly used by anaesthesiologists in a subgroup of patients
with mechanical low back pain arising from structures like facet joints, discus
and sacroiliac joint or combinations of these. In The Netherlands there are
more than 75 certified pain clinics that use these procedures. Indications and
treatment algorithms are described in the evidence based Guideline low back
pain (NVA, NVvN et al. 2011). Although these procedures are commonly used,
strong evidence for their effectiveness is lacking and economic evaluations
have not been performed. This multidisciplinary clinical guideline has
currently been developed with support of the Dutch Society of Medical
Specialists.
There is consensus among anaesthesiologists, as reflected by recommendations in
this guideline, that minimal interventional procedures are effective for
patients with intervertebral disc, facet joint and sacroiliac joint pain or
mixed forms of these. This seems to be in contrast with recently performed
systematic reviews and multidisciplinary international clinical guidelines,
which concluded that there is no strong evidence that supports the
effectiveness of minimal interventional procedures in patients with chronic low
back pain. The main reason is that randomised controlled trials with a low risk
of bias and an adequate sample size are lacking. A recent systematic review
issued by the Dutch Health Insurance Council (CVZ 26/3/2011) showed that the
effectiveness of minimal interventional procedures for the total group of
chronic low back pain is unclear and the cost-effectiveness unknown. Based on
this lack of evidence, the Dutch Health Insurance Council (CVZ) has decided to
advise the Ministry of Health in The Netherlands not to reimburse minimal
interventional procedures for low back pain within the Dutch public health
insurance system. The anaesthesiologists claim that they are only treating a
subgroup of these patients, namely patients with mechanical low back pain. It
is important for care providers to evaluate the effectiveness and
cost-effectiveness of minimal interventional procedures in this subgroup of
patients.
Health insurance companies often have contracts with hospitals agreeing to
reimburse treatment for patients with a specific health problem at specified
costs without specifying the care that will be delivered. The use of diagnostic
and therapeutic interventions is at the discretion of the medical specialists.
For health insurance companies it is important to know whether the care that is
reimbursed is effective and cost-effective.
The aim of his project will be to provide the lacking information. The Dutch
Association of Anaesthesiologists, the Dutch Spine Society, the Dutch Health
Insurance Council (CVZ) and the VUmc and Erasmus MC have all explicitly
acknowledged the importance of this project.

The main objective of this project is to evaluate the effectiveness and
cost-effectiveness of minimal interventional procedures as an add-on to a
multidisciplinary pain program for patients with chronic mechanical low back
pain who are referred to a pain clinic.

Economic evaluation alongside a clinical study with four subgroups for patients
with mechanical low back pain who did not respond to conservative primary care
and were referred to a pain clinic.

The selection of adequate patients in the diagnostic phase, as well as the
invasive treatment of patients is usual care, as described in the Guideline low
back pain (NVA, NVvN et al. 2011).

Based on signs and symptoms, patients with suspicion of a single entity, namely
pain arising from the facet joints or sacroiliac joint will receive a test
block with local anaesthetics. If patients answer *yes* to the question *is
there a 50% or more reduction in pain?* 30 minutes after the test block,
patients will be scheduled to receive a minimal interventional treatment.
Patients with suspicion of pain arising from the intervertebral disc will
receive as test a provocative discography. If this test is positive than they
will be scheduled to receive a minimal interventional treatment.

The minimal interventional procedures will take place according to a
pre-specified approach:
1) Patients with facet joint pain will receive radiofrequency denervation of
the first ramus dorsalis at L3, L4, L5 and S1.
2) Patients with intervertebral disc pain will receive a denervation of the
involved discus.
3) Patients with sacroiliac joint pain will receive radiofrequency denervation
of the ramus dorsalis at L5, S1, S2 and S3.
4) Patients with a combination of the single entities will be randomised after
the clinical diagnosis to a group who receives minimal interventional
treatments (i.e. a combination of the interventions mentioned under 1, 2 and 3)
and a multidisciplinary pain program.

Participating in this trial means that difference in pain and perceived
improvement in functioning will be measured at 3 and 6 weeks after the
intervention; patients have to fill in web based questionnaires (see 7.1. for
the questionnaires) at baseline, 3, 6, 9, and 12 months; all are referred to a
multidisciplinary pain program, and they are randomised to receive invasive
treatment or no additional treatment. Both the multidisciplinary pain program
and the invasive treatment are standard care.