(Cost) effectiveness of open Microdiscectomy vs. percutaneous transforaminal endoscopic discectomy (PTED) for patients with lumbosacral radicular syndrome due to a lumbar disc herniation

Lumbosacral radicular syndrome (LSRS) which is caused by a herniated lumbar
nucleus pulposus (HNP) is a common problem with an annual incidence of 9 per
1000 persons (NHG Standard). The incidence increases in age and is the highest
between 45 to 64 years of age (16 per 1000 persons annually). In The
Netherlands, between 60,000 and 75,000 people develop LSRS annually. In 2009,
ca. 11,000 herniated disc operations were performed in The Netherlands.
Needless to say, the burden to society is tremendous, running in the millions
in direct costs (Deyo 2006; Weinstein 2006) and in Nederland, is estimated to
cost more than 1 billion euro due to direct and indirect costs, most notably
due to production loss (Herniakliniek.nl).

The standard treatment for HNP's is open microdiscectomy. In recent years, a
new surgical technique has been developed, namely percutaneous transforaminal
endoscopic discectomy (PTED). PTED is a technique in which the hernia is
removed through the foramen using a working shaft under endoscopic vision. The
surgery is performed under local anaesthesia on an outpatient basis.

Suggested advantages of this technique include 1) less risk of nerve injury
because the patient is treated under local anesthesia and can indicate to the
surgeon if a nerve root has been damaged; 2) easier for obese patients; 3) less
scarring; 4) less invasive and possibly more successful for those who have had
an earlier operation because a different route is chosen; 5) patient is treated
in the outpatient clinic and can return to home within hours following the
procedure; 6) the procedure is quite successful for those with foraminal
stenosis given that the foramen can be widened; and 7) particularly successful
for those with foraminal and extra-foraminal HNP's which otherwise would be
difficult to approach through the normal procedure. There are, however,
disadvantages such as limited visibility whereby the chance of nerve root
damage would occur. In addition, the chance of recurrent HNP's is larger
because less discus material is removed during PTED. In general, numerous
publications suggest that PTED is safe, that is to say, it has not been
demonstrated that more complications occur with PTED than usual care (i.e. open
microdiscectomy).

It is, however, questionable whether PTED is as effective or at least, no worse
than the standard treatment (i.e. open microdiscectomy). The review by Kamper
et al. (2013) identified three RCTs which examined the effect of PTED compared
to microdiscectomy (Hermantin 1999; Krappel 2001; Mayer 1993). The results
suggest that there is low to very low quality evidence that PTED is no better
for back pain, leg pain, functional status, recovery, return-to-work or
satisfaction at any follow-up moment. However, all three studies were small and
of poor methodological quality, so strong conclusions cannot be drawn.

In recent years, the effect of PTED has been heatedly debated in The
Netherlands. According to the Dutch Health Insurance Council (CVZ), an
operative technique must meet certain requirements in order to be included in
the public health insurance package. CVZ claims there is insufficient evidence
for PTED to be eligible for compensation. As a result, many patients were
forced to pay the costs of treatment out-of-pocket and subsequently, filed a
lawsuit. This issue has also appeared broadly and repeatedly in the media. A
well-known example is the TV program RADAR, which discussed this topic in May
2012 on Dutch television (http://www.trosradar.nl/uitzending).

Research question(s). There are two specific questions to be addressed:

1) Is percutaneous transforaminal endoscopic discectomy (PTED) no worse in
effectiveness than conventional unilateral open microdiscectomy for patients
with symptomatic lumbosacral radicular syndrome (LSRS)?
2) Which therapy (PTED or open microdiscectomy) is more cost-effective?

Research design: A pragmatic, multi-center non-inferiority RCT will be used.
Following the baseline measurements wherein clinical and sociodemographic
measurements are to be collected, patients are to be randomized to one of two
groups: Group 1 will receive standard microdiscectomy (gold standard) and group
2 will receive PTED.

Once recruitment for the RCT has been completed, subjects will be recruited for
an observational study from the same centra that participated in the RCT. The
protocol to be followed will be exactly as the RCT. The reason for this aspect
of the study is to collect more data on complications. These data will be
collected from the patients* chart. Additionally, a form will be completed by
the surgeon should a complication arise.

Standard treatment (Open microdiscectomy)
Open microdiscectomy is to be conducted as follows: General or spinal
anesthesia is to be administered. Verification is to be performed using a C-arm
and the patient is to be positioned prone or in the salaam position. A
paramedian incision is to be performed and the level is to be indicated. Loupe
or microscope magnification is to be used. Laminotomy as well as foraminotomy
is to be performed, if necessary. The amount of degenerative disc material to
be removed is at the discretion of the attending surgeon. Post-operative policy
will be followed and it is expected that the duration of recovery in the
hospital may vary from 2-7 days, but the patient will be discharged as soon as
medically responsible.

Intervention (Percutaneous Transforaminal Endoscopic Discectomy)
PTED is to be conducted as follows: Local anesthesia is to be administered.
Verification of the site to be performed by an image intensifier and depending
upon the patient*s posture, a line is to be drawn from the center of the
herniation. The needle is to be set and position checked. After the needle has
reached the correct position, a guide wire is to be inserted. Following that, a
series of conical rods are to be introduced. After drilling/reaming, in order
to enlarge the neuroforamen, the instruments are to be removed, but the guide
wire is to remain in place and the endoscope with the working channels are to
be introduced via an 8mm cannula. The image intensifier ensures that the
position of the cannula is maintained. Following removal of the hernia, the
cannula and endoscope are removed. The patient is to be treated on an
outpatient basis.

Based upon a recent, published systematic review conducted by our research
group (Kamper et al. 2014), the two techniques are believed to be equivocal in
both effectiveness and safety; therefore, it is believed that subjects
randomized to the intervention (PTED) will not be put at any extra risk. In
general, the risk associated with either procedures (intervention or control
group) are thought to be negligible. Nevertheless, risk which might be
attributed to the intervention (PTED) includes limited visibility whereby nerve
root damage can occur; however, because the patient is awake during the
procedure, the patient can indicate if a nerve root has been penetrated. In
addition, there is the possibility of a recurrent hernia because too little
disc material has been removed. Regardless, all the risks which occur will be
registered. Possible benefits which might be ascribed to the intervention
(PTED) include quicker recovery and return-to-work. The burden to the patients
includes extra visits to the hospital which otherwise might not be necessary,
in addition to the completion of questionnaires and a cost diary (for the
economic evaluation).