Dorsal Root Ganglion (DRG) Therapy

 Refer a Patient for a DRG Consultation 

LIVING LIFE AGAIN: JENIFER'S CHRONIC PAIN STORY

EXPAND YOUR REACH.

TREAT MORE PATIENTS
WITH BETTER RESULTS.

CPS empowers you to treat patients with focal chronic intractable pain, due to complex regional pain syndrome (CRPS), that you couldn't effectively treat before. Learn about the only FDA-approved system specifically designed to stimulate the dorsal root ganglion (DRG), which has been clinically proven to provide superior pain relief over conventional tonic spinal cord stimulation (SCS). DRG therapy expands the range of neurostimulation options you can offer and sets a new standard of care that may help you significantly improve patients' lives.

The ACCURATE study is the largest randomized neurostimulation clinical trial that compares conventional tonic SCS with DRG stimulation to treat CRPS and peripheral causalgia. The findings demonstrate that with DRG therapy, physicians are able to:

1DELIVER SUPERIOR PAIN RELIEF

2GIVE MORE PATIENTS MORE RELIEF

3PROVIDE STABLE LONG-TERM RELIEF TO PATIENTS

SUPERIOR PAIN RELIEF FOR FOCAL CHRONIC INTRACTABLE PAIN

Conventional tonic SCS has been successfully utilized since 1967 as a treatment modality for the management of chronic, intractable pain in the trunk and/or limbs. But for pain locations outside of, or more focal than, the trunk and/or limbs - as seen in chronic intractable pain conditions such as CRPS - conventional tonic SCS has been less successful or has resulted in extraneous stimulation.

TODAY THERE'S A BETTER SOLUTION: STIMULATION OF THE DRG

By stimulating the DRG, we are able to achieve therapeutic coverage and pain relief in difficult-to-treat focal chronic intractable pain conditions. Research has demonstrated that the DRG plays a critical role in the development and maintenance of chronic pain. The DRG's unique pathophysiological response to pain makes it an ideal target for interventional therapies like neurostimulation providing a greater opportunity for therapeutic benefits to be isolated only in the patient's primary area of pain.

DRG stimulation has been proven clinically- superior to conventional tonic SCS in treating lower limb pain associated with CRPS. Patients in the ACCURATE study reported focal chronic intractable pain in anatomical locations like the foot, knee, hip and groin.

At three months, 81.2% of patients receiving DRG stimulation achieved effective pain relief and greater treatment success as compared to 55.7% of patients receiving traditional tonic stimulation. Durability of pain relief was seen after 12 months, with 74.2% of DRG stimulation patients achieving meaningful pain relief and greater treatment success when compared to 53% of patients receiving conventional tonic SCS.

CPS offers the only FDA-approved therapy system to stimulate the DRG, the Axium™ Neurostimulator System. It is comprised of a specially engineered stimulation lead and lead delivery system which interfaces with a stimulator compatible with wireless programmers. This therapy system is designed to precisely deliver stimulation in order to communicate with the DRG and optimize a patient's unique pain therapy requirements.

LEARN MORE: Axium DRG Stimulation Overview

THE SCIENCE BEHIND THE DRG

The DRG is a key epidural, intraspinal nerve structure that houses primary sensory neurons (PSNs) cell bodies. These PSNs embody the primary source of sensory information flow from the periphery to the central nervous system and also represent an important processing point of sensory information. Pain is one type of sensory information that flows and is processed by PSNs within the DRG. Normally, pain represents an important protective sensory experience, but in pathological conditions, pain becomes a chronic condition. Research has shown PSNs in the DRG are critically involved in the development and maintenance of chronic pain. Similarly, these neurons exhibit altered membrane properties such as increased excitability as well as abnormal and ectopic activity.

While these pathophysiologic changes contribute to the chronic pain state, they also likely leave those cells more susceptible to influence by neuromodulation (stimulation) therapies.

DRG THERAPY: POWER TO GIVE MORE PATIENTS MORE RELIEF

DRG therapy expands the range of neurostimulation options you can offer and sets a new standard of care for patients with focal chronic intractable pain, due to CRPS, who are not optimal candidates for other treatments like conventional tonic SCS.

Patients enrolled in the ACCURATE study were diagnosed with CRPS and peripheral causalgia.

The clinical diagnostic criteria (see right page) required for a diagnosis of CRPS were taken from the 1994 consensus statement from the International Association for the Study of Pain (IASP, see ACCURATE study diagnostic criteria).

WHY STIMULATE DRG?

Research has shown that during chronic pain, DRGs associated with injured anatomy exhibit measurable differences in membrane function, which might allow for selective stimulation or activation without recruiting the non-painful neurons. The unique physiology of the DRG makes stimulation highly selective and steerable with difficult-to-treat anatomies, such as the groin, knee, hip and foot. Additionally, the DRG itself is a robust structure with a predictable intraforaminal location in the epidural, intraspinal space. The ganglia are encapsulated in a dural sleeve with minimal cerebral spinal fluid (CSF) surrounding it. This minimal CSF layer in turn may allow for a closer and more stable neuronal-electrode interface.

The DRG's unique pain processes and its anatomical considerations make it an ideal interventional target to treat various focal chronic intractable pain conditions due to CRPS.

ACCURATE STUDY PATIENTS' PRIMARY REGION OF PAIN

PRIMARY REGION OF PAIN DRG GROUP n/N(%) CONTROL GROUP n/N(%)
Right groin 4/76 (5.3) 2/76 (2.6)
Left groin 4/76 (5.3) 7/76 (9.2)
Right buttock 1/76 (1.3) 2/76 (2.6)
Left buttock 2/76 (2.6) 2/76 (2.6)
Right leg 14/76 (18.4) 16/76 (21.1)
Left leg 8/76 (10.5) 11/76 (14.5)
Right foot 21/76 (27.6) 19/76 (25.0)
Left foot 22/76 (28.9) 17/76 (22.4)
P-value (Right groin, left groin, right buttock, left buttock vs. right/left leg vs. right/left foot) 0.5228

This table represents the multiple areas of pain that were identified and treated during the ACCURATE clinical study.

ACCURATE Study Diagnostic Criteria

The CRPS diagnostic criteria were met when the following were present.

Continuing pain that is disproportionate to any inciting event. At least one symptom reported in at least three of the following categories:

- Sensory: Hyperesthesia or allodynia.
- Vasomotor: Temperature asymmetry, skin color changes, skin color asymmetry.
- Sudomotor/edema: Edema, sweating changes or sweating asymmetry.
- Motor/trophic: Decreased range of motion, motor dysfunction (e.g., weakness, tremor, dystonia) or trophic changes (e.g., hair, nail, skin).

At least one sign at time of evaluation in at least two of the following categories.

- Sensory: Evidence of hyperalgesia (to pinprick), allodynia (to light touch, temperature sensation, deep somatic pressure or joint movement).
- Vasomotor: Evidence of temperature asymmetry (> 1 °C), skin color changes or asymmetry.
- Sudomotor/edema: Evidence of edema, sweating changes or sweating symmetry.
- Motor/trophic: Evidence of decreased range of \ motion, motor dysfunction (e.g., weakness, tremor, \ dystonia) or trophic changes (e.g., hair, nail, skin).

No other diagnosis better explaining the signs and symptoms

For peripheral causalgia, the diagnosis required that the subjects' chronic pain was due to damage to a nerve. The pain was required to be in an anatomical area consistent with the innervation pattern of the damaged nerve (or nerves), and generally, in a hyperalgesic state. In some cases, the nerve damage progressed with secondary changes manifesting themselves. However, this was not a diagnostic requirement. Nerve damage typically resulted from blunt trauma (injury) or other types of injury such as post-surgical nerve cutting or lesioning.

STABLE PAIN RELIEF,
NOW WITHIN REACH

Patients with focal chronic intractable pain, due to CRPS, typically have tried multiple therapies in the past without success. But DRG stimulation offers an entirely new option that uses a different approach

In the ACCURATE clinical study, results show stable long-term pain relief at 12 months compared with conventional tonic SCS.

DRG STIMULATION PROVIDES STABLE LONG-TERM PAIN RELIEF COMPARED WITH CONVENTIONAL TONIC SCS

Error bars represent 95% confidence intervals

Your patients deserve every chance at safe, stable and consistent pain management.

The DRG stimulation group demonstrated a numerically greater percent reduction than the control group at the three month interval (84.1% vs. 70.9%) and at 12 months (81.4% vs. 66.5%).

A POSITIVE EXPERIENCE FOR YOUR PATIENTS

Patients receiving conventional tonic stimulation were 7.1 times more likely to report feeling paresthesia in non-painful regions as compared to patients receiving DRG stimulation.

AREA OF PAIN
STIMULATION WITH CONVENTIONAL TONIC SCS
STIMULATION WITH DRG THERAPY

ACCURATE STUDY DESIGN

The objective of the ACCURATE study was to evaluate the safety and effectiveness of DRG stimulation compared to a commercially available SCS device.

152 patients were randomized to a DRG stimulation group or a control group (commercially available SCS device) across 22 investigational sites.

A composite of safety and efficacy was used to define primary endpoint success, provided the patients met the following three criteria:
- ≥ 50% pain relief in their primary area of pain at the end of the trial phase, and
- ≥ 50% pain relief in their primary area of pain at the three month visit post implant, and
- Freedom from stimulation-induced neurological deficit through three months

Three different populations were analyzed:
- Intention-to-treat (ITT): All randomized patients
- Modified intent-to-treat (MITT): All patients that received a trial stimulator
- Implant Only (IO): All patients that received a fully implantable system

KEY TAKEAWAYS FROM THE ACCURATE STUDY:
PROOF THAT DRG THERAPHY WORKS

DRG stimulation has shown to be a superior, effective and safe therapy option for focal chronic intractable pain patients.

152  PATIENTS ENROLLED IN STUDY

The ACCURATE study is the largest randomized, controlled neuromodulation trial conducted in CRPS patients to provide evidence of safety and efficacy for market approval in the United States.

The ACCURATE study met its primary endpoint, demonstrating non-inferiority and superiority in its composite safety and efficacy endpoint compared to conventional SCS in patients.

At three months, 81.2% of DRG patients compared to 55.7% of control patients met the study's primary safety and effectiveness composite endpoint.

ACCURATE IDE RESULTS: PRIMARY ENDPOINT

>80%PATIENTS ENROLLED IN STUDY

The durability of DRG stimulation was confirmed at 12 months in the MITT population, with 74.2% of the patients receiving DRG stimulation (n = 66) having persistent reduction in pain as compared to only 53% of patients receiving conventional SCS (n = 66).

The group with the AxiumTM neurostimulator system demonstrated a numerically greater percent reduction in the visual analog scale (VAS) scores than the control group at three months (84.1% vs. 70.9%) and at 12 months (81.4% vs. 66.5%).

At 12 months, patients receiving conventional tonic stimulation were 7.1 times more likely to report feeling paresthesia in non-painful regions as compared to patients receiving DRG stimulation (38.8% vs. 5.5%).

At three months, in the IO population, 93.3% of patients receiving DRG stimulation achieved the primary endpoint versus 72.2% of patients receiving conventional SCS.

ACCURATE IDE RESULTS: PRIMARY ENDPOINT

The durability of DRG stimulation was confirmed at 12 months in the IO population, with 86.0% of patients receiving DRG stimulation (n = 57) having a ≥ 50% improvement in VAS scores and freedom from a stimulation related neurological deficit vs. 70.0% (n = 50) of patients receiving conventional SCS.

Data from the ACCURATE study suggests that DRG stimulation may offer a meaningful option for patients suffering from chronic intractable pain conditions that are currently underserved by conventional tonic SCS.

DO MORE

TO RELIEVE
CHRONIC PAIN

DRG therapy gives you the power to treat more patients and relieve many cases of focal intractable chronic pain, due to CRPS, more effectively than ever before.

CONTACT YOUR CPS REP to discuss this new option and how you can help your patients find better, more productive and comfortable lives today.

EXPANDING THE TREATABLE PATIENT POPULATION

With RF, SCS and DRG therapy solutions, Comprehensive Pain Specialists offers the most comprehensive interventional pain management portfolio so you have more options to serve more patients.

PHYSICIANS PERFORMING THIS PROCEDURE

Dr. Peter Kroll, M.D.

Dr. Richard Muench, M.D.

Dr. Donald Jones, M.D.

Dr. Kyle Payne, M.D.

For a new patient consultation for DRG in Tennessee or Bowling Green, KY please call

615.348.6226

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