Current through Register Vol. 50, No. 9, September 20, 2024
A.
When considering operative intervention in chronic pain management, the
treating physician must carefully consider the inherent risk and benefit of the
procedure. All operative intervention should be based on a positive correlation
with clinical findings, the clinical course, and diagnostic tests. A
comprehensive assessment of these factors should have led to a specific
diagnosis with positive identification of the pathologic condition. Operative
treatment is indicated when the natural history of surgically treated lesions
is better than the natural history for non-operatively treated lesions.
1. Surgical procedures are seldom meant to be
curative and should be employed in conjunction with other treatment modalities
for maximum functional benefit. Functional benefit should be objectively
measured and includes the following:
a.
return-to-work or maintaining work status;
b. fewer restrictions at work or performing
activities of daily living (ADLs);
c. decrease in usage of medications
prescribed for the work-related injury;
d. measurable functional gains, such as
increased range-of-motion or documented increase in strength;
e. education of the patient should include
the proposed goals of the surgery, expected gains, risks or complications, and
alternative treatment
2.
Education of the patient should include the proposed goals of the surgery,
expected gains, risks or complications, and alternative treatment.
a. Description - Neurostimulation is the
delivery of low-voltage electrical stimulation to the spinal cord or peripheral
nerves to inhibit or block the sensation of pain. This is a generally accepted
procedure that has limited use. May be most effective in patients with chronic,
intractable limb pain who have not achieved relief with oral medications,
rehabilitation therapy, or therapeutic nerve blocks, and in whom the pain has
persisted for longer than six months. Particular technical expertise is
required to perform this procedure and is available in some neurosurgical,
rehabilitation, and anesthesiology training programs and fellowships.
Physicians performing this procedure must be trained in neurostimulation
implantation and participate in ongoing injection training workshops, such as
those sponsored by the Internal Society for Injection Studies or as sponsored
by implant manufacturers.
b.
Complications - May include paraplegia, epidural hematoma, epidural hemorrhage,
undesirable change in stimulation, seroma, CSF leakage, infection, erosion,
allergic response, hardware malfunction or equipment migration, pain at
implantation site, loss of pain relief, chest wall stimulation, and other
surgical risks.
c. Surgical
Indications - Failure of conservative therapy including active and/or passive
therapy, medication management, or therapeutic injections. Preauthorization is
required. Habituation to narcotic analgesics in the absence of a history of
addictive behavior does not preclude the use of neurostimulation. Only patients
who meet the following criteria should be considered candidates for
neurostimulation:
i. A diagnosis of a
specific physical condition known to be chronically painful has been made on
the basis of objective findings; and
ii. All reasonable surgical and non-surgical
treatment has been exhausted; and
iii. Pre-surgical psychiatric or
psychological evaluation has been performed and has demonstrated motivation and
long-term commitment without issues of secondary gain; and
iv. There is no evidence of addictive
behavior. (Tolerance and dependence to narcotic analgesics are not addictive
behaviors and do not preclude implantation.); and
v. The topography of pain and its underlying
pathophysiology are amenable to stimulation coverage (the entire painful area
has been covered); and
vi. A
successful neurostimulation screening test of two-three days. A screening test
is considered successful if the patient (a) experiences a 50 percent decrease
in pain, which may be confirmed by visual analogue scale (VAS), and (b)
demonstrates objective functional gains or decreased utilization of pain
medications. Functional gains may be evaluated by an occupational therapist
and/or physical therapist prior to and before discontinuation of the
trial.
vii. For spinal cord
stimulation, a temporary lead is implanted at the level of pain and attached to
an external source to validate therapy effectiveness. (For peripheral nerve
screening, a nerve block is performed to define the specific nerve branch but
if multiple branches are involved, a screening test for spinal cord stimulation
may be indicated.) Long-term functional improvement is anticipated when
objective functional improvement has been observed during time of
neurostimulation screen exam.
d. Contraindications - Unsuccessful
neurostimulation test either inability to obtain functional improvement or
reduction of pain, those with cardiac pacemakers, patient unable to properly
operate the system. It should not be used if future MRI is planned.
e. Operative Treatment Implantation of
stimulating leads connected by extensions to either an implanted
neurostimulator or an implanted receiver powered by an external transmitter.
The procedure may be performed either as an open or a percutaneous procedure,
depending on the presence of epidural fibrosis and the anatomical placement
required for optimal efficacy.
f.
Post-Operative Considerations MRI is contraindicated after placement of
neurostimulators.
g. Post-Operative
Therapy Active and/or passive therapy should be employed to improve function.
Implantable stimulators will require frequent monitoring such as adjustment of
the unit and replacement of batteries.
3. Smoking may affect soft tissue healing
through tissue hypoxia. Patients should be strongly encouraged to stop smoking
and be provided with appropriate counseling by the physician. If a treating
physician recommends a specific smoking cessation program peri-operatively,
this should be covered by the insurer. Physicians may monitor smoking cessation
with laboratory tests such as cotinine levels. The surgeon will make the final
determination as to whether smoking cessation is required prior to surgery.
Similarly, patients with uncontrolled diabetes are at increased risk of
post-operative infection and poor wound healing. It is recommended that routine
lab work prior to any surgical intervention include a hemoglobin A1c. If it is
higher than the recommended range, the surgery should be postponed until
optimization of blood sugars has been achieved.
4. Prior to surgical intervention, the
patient and treating physician should identify functional operative goals and
the likelihood of achieving improved ability to perform activities of daily
living or work activities, and the patient should agree to comply with the pre-
and post-operative treatment plan including home exercise. The provider should
be especially careful to make sure the patient understands the amount of
post-operative therapy required and the length of partial- and full-disability
expected post-operatively.
5.
Monitored anesthesia care is acceptable for diagnostic and therapeutic
procedures.
6. Neurostimulation
a. Description-Spinal cord stimulation (SCS)
is the delivery of low-voltage electrical stimulation to the spinal cord or
peripheral nerves to inhibit or block the sensation of pain. The system uses
implanted electrical leads and a battery powered implanted pulse generator
(IPG).
b. There is some evidence
that SCS is superior to reoperation in the setting of persistent radicular pain
after lumbosacral spine surgery, and there is some evidence that SCS is
superior to conventional medical management in the same setting. Success was
defined as achieving 50 percent or more pain relief. However, the study could
not demonstrate increased return to work. Some functional gains have been
demonstrated. These findings may persist at three years of follow-up in
patients who had an excellent initial response and who are highly
motivated.
c. There is some
evidence that a higher-frequency, 500Hz to 10 KHz spinal cord stimulator is
more effective than a traditional low frequency 50 Hz stimulator in reducing
both back pain and leg pain in patients who have had a successful trial of an
external stimulator. Two-thirds of the patients had radiculopathy and one-half
had predominant back pain. The higher frequency device appears to lead to
greater patient satisfaction than the low frequency device, which is likely to
be related to the fact that the higher frequency device does not produce
paresthesias in order to produce a pain response. In contrast to the low
frequency stimulator, which requires recharging about twice per month, the
higher frequency stimulator is recommended for every one to three days
recharging for 0.5 to 3 hours. A United Kingdom study of cost effectiveness for
high frequency spinal cord stimulators found high cost effectiveness compared
to traditional non-rechargeable or rechargeable stimulators, re-operation, or
medical management.
d. Some
evidence shows that SCS is superior to re-operation and conventional medical
management for severely disabled patients who have failed conventional
treatment and have Complex Regional Pain Syndrome (CRPS I) or failed back
surgery with persistent radicular neuropathic pain.
e. A recent randomized trial found that
patients with spinal cord stimulators for CRPS preferred different types and
levels of stimulation for pain relief. No difference was found between
40,500Hz, 1200 Hz, and 10KHz levels or burst stimulation.
f. SCS can be used for patients who have CRPS
II. Spinal cord stimulation for spinal axial pain has traditionally not been
very successful. Recent technological advances such as higher frequency and
burst stimulation have demonstrated better results for axial spine pain. These
technologically superior spinal cord stimulators are recommended for axial
spine pain.
g. SCS may be most
effective in patients with CRPS I or II who have not achieved relief with oral
medications, rehabilitation therapy, or therapeutic nerve blocks, and in whom
the pain has persisted for longer than six months.
h. It is particularly important that patients
meet all of the indications before a permanent neurostimulator is placed
because several studies have shown that workers compensation patients are less
likely to gain significant relief than other patients. As of the time of this
guideline writing, spinal cord stimulation devices have been FDA approved as an
aid in the management of chronic intractable pain of the trunk and/or limbs,
including unilateral and bilateral pain associated with the following: failed
back surgery syndrome, intractable low back pain, leg pain and arm
pain.
i. Particular technical
expertise is required to perform this procedure and is available in some
neurosurgical, rehabilitation, and anesthesiology training programs and
fellowships. Physicians performing this procedure must be trained in
neurostimulation implantation and participate in ongoing training workshops on
this subject, such as those sponsored by the American Society of Interventional
Pain Practitioners (ASIPP), North American Neuromodulation Society (NANS), or
as sponsored by implant manufacturers. Permanent electrical lead and IPG
placement should be performed by surgeons (orthopedic or neurosurgery) with
fellowship training in spine based surgical interventions or other physicians
who have completed an Accreditation Council for Graduate Medical Education
(ACGME) accredited pain medicine fellowship or training and have completed the
required number of supervised implantations during fellowship or
training.
j. Complications-Serious,
less common complications include spinal cord compression, paraplegia, epidural
hematoma, epidural hemorrhage, undesirable change in stimulation, seroma, CSF
leakage, infection, erosion, allergic response. Other complications consist of
dural puncture, hardware malfunction or equipment migration, pain at
implantation site, loss of pain relief, chest wall stimulation, and other
surgical risks. In recent studies, device complication rates have been reported
to be 25 percent at six months, 32 percent at 12 months, and 45 percent at 24
months. The most frequent complications are reported to be electrode migration
(14 percent) and loss of paresthesia (12 percent), up to 24 percent required
additional surgery. In a recent review of spinal stimulation, 34.6 percent of
all patients reported a complication, most of them being technical
equipment-related issues or undesirable stimulation.
k. Surgical Indications-Patients with
established CRPS I or II, or radicular or trunk pain, or a failed spinal
surgery with persistent functionally limiting radicular pain greater than axial
pain, who have failed conservative therapy including active and/or passive
therapy, pre-stimulator trial psychiatric evaluation and treatment, medication
management, or therapeutic injections. Traditional SCS is not recommended for
patients with the major limiting factor of persistent axial spine pain. Higher
frequency stimulators may be used for patients with predominantly axial back
pain or trunk pain. Traditional or other SCS may be indicated in a subset of
patients who have a clear neuropathic radicular pain (radiculitis) with or
without previous surgery. The extremity pain should account for at least 50
percent or greater of the overall back and leg pain experienced by the patient.
Prior authorization is required. Habituation to opioid analgesics in the
absence of a history of addictive behavior does not preclude the use of SCS.
Patients with severe psychiatric disorders, issues of secondary gain, and one
or more primary risk factors are not candidates for the procedure. The
prognosis worsens as the number of secondary risk factors increases.
Approximately, one third to one half of patients who qualify for SCS can expect
a substantial long-lasting pain relief; however, it may not influence allodynia
and hypesthesia. Patients expectations need to be realistic, and therefore,
patients should understand that the SCS intervention is not a cure for their
pain but rather a masking of their symptomatology which might regress over
time. There appears to be a likely benefit of up to three years, although some
practitioners have seen benefits persist for longer periods.
i. Prior to surgical intervention, the
patient and treating physician should identify functional operative goals and
the likelihood of achieving improved ability to perform activities of daily
living or work, as well as possible complications. The patient should agree to
comply with the pre- and post-operative treatment plan including home exercise.
The provider should be especially careful to make sure the patient understands
the amount of post-operative therapy required and the length of partial- and
full-disability expected post-operatively.
ii. Informed decision making should be
documented for all invasive procedures. This must include a thorough discussion
of the pros and cons of the procedure and the possible complications as well as
the natural history of the identified diagnosis. Since many patients with the
most common conditions will improve significantly over time, without invasive
interventions, patients must be able to make well-informed decisions regarding
their treatment.
iii. Smoking may
affect soft tissue healing through tissue hypoxia. Patients should be strongly
encouraged to stop smoking and be provided with appropriate counseling by the
physician. If a treating physician recommends a specific smoking cessation
program perioperative, this should be covered by the insurer. Typically the
patient should show some progress toward cessation at about six weeks.
Physicians may monitor smoking cessation with laboratory tests such as cotinine
levels. The surgeon will make the final determination as to whether smoking
cessation is required prior to surgery. Patients with demonstrated success may
continue the program up to three months or longer if needed based on the
operative procedure. Smoking cessation should continue throughout the
post-operative period. Refer to Smoking Cessation Medications and Treatment for
further details.
iv. Patients must
meet the following criteria in order to be considered candidates for
neurostimulation:
(a). Traditional or other
SCS may be indicated in a subset of patients who have a clear neuropathic or
radicular pain (radiculitis) or trunk pain; are not candidates for surgical
intervention on the spine; have burning pain in a distribution amenable to
stimulation coverage and have pain at night not relieved by position. The
extremity pain should account for at least 50 percent or greater of the overall
arm or leg and back pain experienced by the patient. Higher frequency
stimulators may be used for patients with predominantly axial back
pain.
(b). Prior to the stimulator
trial, a comprehensive psychiatric or psychological evaluation, and a chronic
pain evaluation. Refer to Personality/Psychological Evaluation for Pain
Management, for more information. This evaluation should include a standardized
detailed personality inventory with validity scales (e.g., MMPI-2, MMPI-2-RF,
or PAI); pain inventory with validity measures (e.g., BHI 2, MBMD); clinical
interview and complete review of the medical records. The psychologist or
psychiatrist performing these evaluations should not be an employee of the
physician performing the implantation. This evaluation must be completed, with
favorable findings, before the screening trial is scheduled. Before proceeding
to a spinal stimulator trial, the evaluation should find the following:
(i). no indication of falsifying
information;
(ii). no indication of
invalid results on testing; and
(iii). no primary psychiatric risk factors or
"red flags" (e.g., psychosis, active suicidality, severe depression, or
addiction). (Note that tolerance and dependence to opioid analgesics are not
addictive behaviors and do not preclude implantation); and
(iv). a level of secondary risk actors or
"yellow flags" (e.g., moderate depression, job dissatisfaction, dysfunctional
pain conditions) judged to be below the threshold for compromising the patients
ability to benefit from neurostimulation;
(v). the patient is cognitively capable of
understanding and operating the neurostimulation control device; and
(vi). the patient is cognitively capable of
understanding and appreciating the risks and benefits of the procedure;
and
(vii). the patient is familiar
with the implications of having an implant, can accept the complications,
potential disfigurement, and effort it takes to maintain the device;
and
(viii). the patient is
cognitively capable of understanding the course of injury both with and without
neurostimulation; and
(ix). the
patient has demonstrated a history of motivation in and adherence to prescribed
treatments; and
(x). the patient
understands the work related restrictions that may occur with placement of the
stimulator. All reasonable surgical and non-surgical treatment has been
exhausted; and
(xi). the topography
of pain and its underlying pathophysiology are amenable to stimulation coverage
(the entire painful area has been covered); and
(xii). a successful neurostimulation
screening test of at least three to seven days for a percutaneous trial or 7 to
10 days for an open surgically implanted trial lead.
(c). For a spinal cord neurostimulation
screening test, a temporary lead is either implanted surgically with an
incision or percutaneously attached to the skin and attached to an external
source to validate therapy effectiveness. A screening test is considered
successful if the patient meets both of the following criteria:
(a) experiences a 50 percent decrease
radicular or CRPS in pain, which may be confirmed by visual analogue scale
(VAS) or Numerical Rating Scale (NRS), and
(b) demonstrates objective functional gains
or decreased utilization of pain medications.
(i). Objective, measurable, functional gains
must be evaluated by the primary treating physician prior to and before
discontinuation of the trial. If the trial is with a surgically implanted lead
below the skin, then the trial is from 7 to 10 days. If the trial is
percutaneous, then the trial is three to seven days. Functional gains may
include: standing, walking, positional tolerance, upper extremity activities,
increased social participation, or decreased medication use.
l. Contraindications
i. unsuccessful SCS test-inability to obtain
objective, documented, functional improvement or reduction of pain;
ii. those with cardiac pacemakers should be
evaluated on an individual basis as some may qualify for surgery;
iii. patients who are unable to properly
operate the system;
iv. patients
who are anti-coagulated and cannot be without anticoagulation for a few days
(e.g., patients with artificial heart valves);
v. patients with frequent severe infections;
vi. patients for whom a future MRI
is planned unless the manufacturer has approval for the body part that will be
the subject of the MRI.
m. Operative Treatment-Implantation of
stimulating lead or leads connected by extensions to either an implanted
neurostimulator or an implanted receiver powered by an external transmitter.
The procedure may be performed either as an open or a percutaneous procedure,
depending on the presence of epidural fibrosis and the anatomical placement
required for optimal efficacy. During the final procedure for non-high
frequency devices or for those without surgically implanted trial leads, the
patient must be awakened to establish full coverage from the placement of the
lead. One of the most common failures is misplaced leads. Functional
improvement is anticipated for up to three years or longer when objective
functional improvement has been observed during the time of neurostimulation
screening exam.
n. Post-Operative
Considerations
i. MRI may be contraindicated
depending on the model and implant location.
ii. Work restrictions postplacement include
no driving when active paresthesias are present. This does not apply to higher
frequency stimulators as no paresthesia is present. Thus, use of potentially
dangerous or heavy equipment while the lower frequency simulator is active is
prohibited. The physician may also limit heavy physical labor to prevent lead
dislodgement.
o.
Post-Operative Therapy-Active and/or passive therapy should be employed to
improve function. Implantable stimulators will require frequent monitoring such
as adjustment of the unit and replacement of implanted batteries. Estimated
battery life of SCS implantable devices is usually 5 to 10 years depending on
the manufacturer.
7.
Dorsal Root Ganglion Stimulator (See Neurostimulation)
8. Peripheral Nerve Stimulation-This modality
should only be employed with a clear nerve injury or when the majority of pain
is clearly in a nerve distribution in patients who have completed six months of
other appropriate therapy including the same pre-trial psychosocial evaluation
and treatment as are recommended for spinal cord stimulation. A screening trial
should take place over three to seven days and is considered successful if the
patient meets both of the following criteria:
a. experiences a 50 percent decrease in pain,
which may be confirmed by Visual Analogue Scale (VAS) or Numerical Rating Scale
(NRS); and
b. demonstrates
objective functional gains or decreased utilization of pain medications. It may
be used for proven occipital, ulnar, median, and other isolated nerve injuries.
9. Intrathecal drug
delivery-recommended in patients in whom other conservative measures have
failed or in those requiring high dose oral opiates or experiencing side
effects to control pain or in cases of spasticity or uncontrolled muscle
spasms. Oral pain medication would not be appropriate for chronic pain in
conjunction with an Intrathecal pain pump, except for up to the initial ten
days after implant for purpose of postop incisional pain or weaning and
stopping oral opiates. Treatment for concomitant acute pain separate from
chronic pain can combine oral opiates and pump medication at reduced doses
orally. Pumps require refilling every one to six months for the life of the
patient. More than one medication may be needed in the pump. Once implanted the
managing physician must arrange for continuity of care for refills and or pump
adjustments. Oral opiates should be stopped 7-10 days after implantation or
pump and Intrathecal catheter and pump should be titrated to control chronic
pain. A PTM (Patient therapy manager) may be used for breakthrough pain. Acute
pain may be treated concomitantly with short courses or oral opiates.
Intrathecal pumps may be considered when dystonia and spasticity are dominant
features or when pain is not able to be managed using any other non-operative
treatment or in cases inadequate opiate management by other routes. Specific
brands of infusion systems have been FDA approved for the following: chronic
intraspinal (epidural and intrathecal) infusion of preservative-free morphine
sulfate sterile solution in the treatment of chronic intractable pain, chronic
infusion of preservative-free ziconotide sterile solution for the management of
severe chronic pain, and chronic intrathecal infusion of baclofen for the
management of severe spasticity. Other medications commonly used and acceptable
in the pump as defined in the The Polyanalgesic Consensus Conference (PACC)
Recommendations on Intrathecal Drug Infusion Systems Best Practices and
Guidelines 2017 Tim Deer et al "Neuromodulation: Technology at the Neural
Interface".
a. Due to lack of proven efficacy
and safety, the following medications are not recommended: magnesium,
benzodiazepines, neostigmine, tramadol, and ketamine.
b. Description. This mode of therapy delivers
small doses of medications directly into the cerebrospinal fluid.
c. Complications. Intrathecal delivery is
associated with significant complications, such as infection, catheter
disconnects, CSF leak, arachnoiditis, pump failure, nerve injury, and
paralysis.
i. Typical adverse events reported
with opioids (i.e., respiratory depression, tolerance, and dependence) or
spinal catheter-tip granulomas that might arise during intrathecal morphine or
hydromorphone treatment have not currently been recorded for ziconotide. The
most common presentation of an intraspinal mass is a sudden increase in dosage
required for pain relief, with new neurologic defects secondary to a mass
effect. Technical errors can lead to drug overdose which can be
life-threatening. Withdrawal or death can occur if pump refill is denied or
prevented.
ii. Surveys have shown
technical problems requiring surgical correction in 18 percent to 40 percent of
patients. CSF leakage may occur with multiple dural punctures since the needle
is larger than the spinal catheter. Follow PACC guidelines on efficacy. The
function of the pump depends on its electronic power source, which may be
disrupted by the magnet of an MRI; therefore, after the patient has an MRI, the
pump should be checked immediately after the MRI to ensure that it does not
need to be restarted. The delivery rate can be affected by atmospheric pressure
and body temperature. Some pumps are recommended to be emptied before the MRI
and refilled immediately after the MRI.
d. Indications. Clinical studies are
conflicting, regarding long-term, effective pain relief in patients with
non-malignant pain. This treatment must be have preauthorization and the
recommendation of at least one physician experienced in chronic pain
management. The procedure should be performed by physicians with documented
experience.
i. Prior to surgical intervention,
the patient and treating physician should identify the possible functional
operative goals and the likelihood of achieving improved ability to perform
activities of daily living or work, as well as possible complications. The
patient should agree to comply with the pre- and post-operative treatment plan
including home exercise. The provider should be especially careful to make sure
the patient understands the amount of post-operative therapy required and the
length of partial- and full-disability expected post-operatively.
ii. Informed decision-making should be
documented for all invasive procedures. This must include a thorough discussion
of the pros and cons of the procedure and the possible complications as well as
the natural history of the identified diagnosis. Since many patients with the
most common conditions will improve significantly over time, without invasive
interventions, patients must be able to make well-informed decisions regarding
their treatment.
e. This
small eligible sub-group of patients must meet all of the following
indications:
i. a diagnosis of a specific
physical condition known to be chronically painful has been made on the basis
of objective findings; and
ii. all
reasonable surgical and non-surgical treatment has been exhausted including
failure of conservative therapy including active and/or passive therapy,
medication management, or therapeutic injections; and
iii. pre-trial psychiatric or psychological
evaluation has been performed (same as for SCS); and
iv. there is no evidence of current addictive
behavior. (Tolerance and dependence to opioid analgesics are not addictive
behaviors and do not preclude implantation.); and
v. it is recommended that patients be tapered
off of opioids before the trial or keep on same dose and wean and stop within
two weeks post implant or wean and stop two to three weeks before trial per
PACC Guidelines for Trialing; and
vi. a successful trial of continuous infusion
by a percutaneous spinal infusion pump for a minimum of 24 hours or by bolus
infusion. A screening test is considered successful if the patient (a)
experiences a 50 percent decrease in pain, which may be confirmed by VAS, and
(b) demonstrates objective functional gains or decreased utilization of other
pain medications.
f.
Contraindications. Infection, body size insufficient to support the size and
weight of the implanted device. Patients with other implanted programmable
devices should be given these pumps with caution since interference between
devices may cause unintended changes in infusion rates.
10. Dorsal Nerve Root Resection: This
procedure is not recommended. There exists the possibility of complications
including unintended extensive nerve damage causing significant motor or
sensibility changes from larger than anticipated lesioning of the ganglia at
the dorsal ganglia level. For radio-frequency ablation refer to Radio Frequency
Ablation-Dorsal Nerve Root Ganglion.
AUTHORITY
NOTE: Promulgated in accordance with
R.S.
23:1203.1.