Radiofrequency (RF) neurotomy – cervical medial branch

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Considered Judgement Form
This form is a checklist of issues that may be considered by the Purchasing Guidance Advisory Group when
making purchasing recommendations.
PGAG Meeting 7th June 2006:
TOPIC: Radiofrequency (RF) Neurotomy: Cervical Medial Branch
RF neurotomy (also known as RF denervation) is a procedure during which the tip of an electrode,
which has been placed beside a nerve, is heated in order to coagulate the proteins inside that nerve.
Successful treatment prevents the nerve from conducting impulses, including pain messages, until the
nerve recovers. Recovery of the nerve typically occurs after about a year.
The zygapophyseal (facet or z-) joints of the cervical spine receive their nerve supply from nerves
called the medial branches of the cervical dorsal rami. RF neurotomy is applied to the medial branches
to treat neck pain, with or without radiation to the head or shoulder girdles, when its source is one of
the cervical z-joints. Each joint, except C2-3, is supplied by two medial branches and treatment of two
nerves is therefore required to relieve pain from one joint.
Radiofrequency Neurotomy has been used for the following conditions in the papers appraised for this
review:
•
Whiplash injury with or without specifically diagnosed zygapophyseal (z-) joint pain.
•
Painful cervical z-joint attributed to a motor vehicle accident and experienced > 3 months
following that accident.
•
Neck pain > 3 months after a motor vehicle accident.
•
Cervical z-joint pain in patients involved in a motor vehicle accident ≥ 20 weeks earlier.
•
Neck pain with or without radiation to the head or shoulder girdle.
The procedure is performed under local anaesthesia. An electrode is carefully introduced into the side
of the neck under X-ray guidance and placed with precision parallel to the target nerve. When
satisfactory placement of the electrode has been confirmed, a lesion is created by heating the tip of the
electrode to 80 - 85°C for up to 90 seconds. More than one lesion is usually required to ensure that the
nerve has been coagulated. The same procedure is then repeated on the same nerve at a different angle
because relief persists for longer if a longer section of nerve is treated. The same procedure is then
usually repeated at an adjacent level to treat the other nerve that supplies the painful joint.
RF neurotomy of the cervical medial branches is only indicated in cases where pain has been
completely relieved by controlled diagnostic cervical medial branch blocks. It is performed in a
facility such as a radiology suite or operating theatre where there is access to a C-arm fluoroscope.
It is performed by a doctor who has appropriate training in the conduct of the procedure. In the New
Zealand setting this would most likely be a musculoskeletal physician, anaesthetist or radiologist. The
assistance of a radiographer is required during the procedure.
In the last 5 months (November 05- April 06) 30 claims for RF have been made at a total cost of
$206,895.02 (these could include procedures in the lumbar and cervical regions).
Details of the review methodology and critical appraisal can be found on www.acc.co.nz/ipm.
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1. Volume of evidence
Comment here on any issues concerning the quantity of evidence available on this topic and its methodological quality.
One health technology assessment (Bassett et al. 2001), one guideline (Manchikanti et al. 2003), two systematic reviews
(Niemisto et al. 2003; Manchikanti et al. 2002) and two case series (Pevsner et al. 2003; Sapir & Gorup 2001) provided
information on the effectiveness of RF neurotomy of the cervical medial branch. The health technology assessment focused
on whiplash injury but the guideline and systematic reviews were more broad-based (i.e. they also covered ‘medial branch’ or
‘neck and back injury’).
The high quality systematic review (Niemisto et al. 2003) along with the medium quality HTA (Bassett et al., 2001, guideline
(Manchikanti et al., 2003) and additional systematic review (Manchikanti et al., 2002) all included one small, high quality
randomised controlled trial (RCT) (Lord et al. 1996 1 ).
The additional observational studies were of low to medium quality (Sapir & Gorup 2001, (Pevsner et al. 2003).
Both the Lord et al. and Sapir & Gorup studies used controlled diagnostic blocks to check that appropriate patients were
selected.
The Lord et al. RCT was carried out in 1996 and has not been replicated.
2. Consistency
Comment here on the degree of consistency demonstrated by the availability of evidence. Where there are conflicting results,
indicate how the group formed a judgement as to the overall direction of the evidence.
Consistent evidence of short effectiveness from one small RCT (reported in a number of secondary publications) and one case
series. Both studies used controlled diagnostic blocks. One additional case series reported similar positive effect; this study
did not use a controlled diagnostic block.
3. Applicability
Comment here on the extent to which the evidence is directly applicable in the New Zealand setting. Comment here on how
reasonable it is to generalise from the results of the studies used as evidence to the target population for this guideline.
The procedure is carried out in a highly selected group of patients. The applicability of this procedure to the New Zealand
setting was questioned, as the procedure is time consuming, may be considered to be technician-dependent and has only been
carried out successfully in Newcastle, Australia.
4. Clinical Impact
Comment here on the potential clinical impact that the intervention in question might have – e.g. size of patient population;
magnitude of effect; relative benefit over other management options; resource implications; balance of risk and benefit.
Lord et al. (n=24) found that a greater number of patients were pain-free at 7 month follow-up when treated with RF
neurotomy at 90°C for 90 seconds compared with a sham procedure. The median number of days to return of pain was
significantly longer in the treatment group.
Sapir and Gorup found that half of the 50 patients treated at 80°C for 90 seconds were free of symptoms at 12 months follow
up (Sapir & Gorup, 2001).
Pevsner et al. 2003 (n=122) reported successful outcomes in selected cases up to 18 months.
One RCT that suggests that this procedure may be promising, with potential harm outweighed by potential benefit.
Adverse Events and Complications
Lord et al. reported a longer period of days of intervention-related pain in the RF lesion group (13.5 versus 3.5 days). Other
side effects only occurred among the RF lesion group: minor numbness / dysesthesia in 5 and psoriatic rash in 1 patient.
Sapir and Gorup did not report side effects.
Pevsner et al reported discomfort at the operative site in 27 of the 122 patients participating in the study.
A case series by Govind et al. (2003) (n=49) noted numbness in 97%, ataxia in 95%, dysaesthesia in 55%, hypersensitivity in
15% and itch in 10% of patients.
1
Lord SM, Barnsley L, Wallis BJ, et al. Percutaneous radio-frequency neurotomy for chronic cervical
zygapophyseal-joint pain. N Engl J Med 1996;335(23):1721-6.
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5. Other Factors
Indicate here any other factors that you took into account when assessing the evidence base.
Need to repeat the procedure – median effect 263 days
Low numbers to harm, adverse effects not severe or long lasting
“? Chronically applied pain relief”
6. Evidence Statement (IPM Advisory Group)
Please summarise the development group’s synthesis of the evidence relating to this
key question, taking all the above factors into account, and indicate the evidence
level which applies.
There is medium quality evidence that radiofrequency neurotomy of the cervical
medial branch is effective (for a median of nine months) in the treatment of adults
with persistent neck pain following motor vehicle accident.
7. Recommendation (IPM Advisory Group)
What recommendation(s) does the guideline development group draw from this
evidence? Please indicate the grade of recommendation(s) and any dissenting
opinion within the group.
This procedure should only be considered in a research setting with appropriate
ethics approval by a practitioner who is appropriately trained and competent,
preferably in a placebo controlled study.
Weight and
consistency of
evidence*
Evidence
Level**
~
~
Grade of
Recommendation***
B
8. Purchasing Recommendation (PGAG)
Purchase radiofrequency neurotomy of the cervical medial
branch on a case by case basis in those centres, with
specifically trained personnel, where protocols are
currently in place and which collect procedural data that is
available to guide ACC in future purchasing decisions.
PGAG Discussion
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*Weight and consistency of evidence:
+ good
~ moderate
- poor
**Evidence level:
+ strong studies where all or most of the validity criteria are met
~ studies where not all the of the criteria are met but the results of the study are not likely to be affected
- weak studies where very few of the validity criteria are met and there is a high risk of bias
***Grade of recommendation:
A = The recommendation (course of action) is supported by good evidence
The evidence consists of results from studies of strong design for answering the question addressed.
B = The recommendation (course of action) is supported by fair evidence
The evidence consists of results from studies of strong design for answering the question addressed but there is some uncertainty
attached to the conclusion either because of inconsistencies among the results of the studies or because of minor flaws; or, the
evidence consists of results from weaker study designs for the question addressed but the results have been confirmed in separate
studies and are reasonably consistent. There is fair evidence that the benefits of the course of action being proposed outweigh the
harms.
C = The recommendation (course of action) is supported by expert opinion only
For some outcomes, trials or studies cannot be or have not been performed and practice is informed by expert opinion only.
I = No recommendation can be made because the evidence is insufficient
Evidence for a course of action is lacking, of poor quality or conflicting and the balance of benefits and harms cannot be
determined.
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