ReActiv8

ReActiv8 is an implantable device designed to electrically stimulate nerves to key stabilizing muscles of the lumbar spine thereby activating these muscles.

What is the clinical Problem?

The strongest stabilizer of the lower back is the multifidus muscle which attaches to the spine at multiple levels. Its segmental activation is orchestrated by the central nervous system in response to a variety of sensory and proprioceptive stimuli.

Joint pain which originates from a strain or sprain injury of one of the ligaments, tendons, joint capsules or discs can lead to disruption of motor control and compromised spine stability. Inhibition of the multifidus allows spine joints to move beyond their pain free zone, and leads to increased pain intensity and possible re-injury. The result is an ongoing cycle of chronic pain, inhibition and eventually muscle atrophy.

Several studies have demonstrated that ultrasound image guided exercise programs targeting multifidus motor control can improve low back pain¹. Treatment guidelines² recommend completion of individualized exercise programs before other options are considered.

The use of electrical stimulation to reactivate the motor control system is well established for other skeletal joints and stabilizing muscles (e.g.: quadriceps inhibition after knee surgery³).

Results of a recently presented feasibility study⁴ suggest that electrical stimulation of the medial branch of the dorsal ramus to activate the multifidus may indeed lead to improvements in chronic low back pain.

¹ Ghamkhar, L., Emami, M., Mohseni-Bandpei, M. A., & Behtash, H. (2011). Application of rehabilitative ultrasound in the assessment of low back pain: a literature review. Journal of bodywork and movement therapies, 15(4), 465–77. doi:10.1016/j.jbmt.2010.07.003
² Airaksinen, O. et al. Chapter 4. European guidelines for the management of chronic nonspecific low back pain. Eur. Spine J. 15 Suppl 2, S192–300 (2006).
³ Gondin, J., Guette, M., Ballay, Y. & Martin, A. Electromyostimulation training effects on neural drive and muscle architecture. Med. Sci. Sports Exerc. 37, 1291–9 (2005).
⁴ Van Buyten, JP. et al. A New Therapy for Patients with Chronic Low Back Pain (CLBP): Results of a European Multicenter Feasibility Study. in Int. Neuromodulation Soc. Congr. 10, (2013). Neuromodulation 2013; 16: e176,e177.

How does ReActiv8 work?

Many studies show that restoration of muscle activation is an important step in the treatment of chronic low back pain.^1,2

ReActiv8 is a small implanted device which stimulates the nerves responsible for activating the key muscles that stabilize the lower back.

Similar to exercise programs used to restore muscle control³, you deliver ReActiv8 sessions twice a day for about 30 minutes. During the sessions ReActiv8 will activate the muscles in your lower back. You are always in control of the stimulation session via a handheld wireless remote control.

Over time, the stimulated activation may help your brain and body learn how to better control the muscles in between sessions. Restoration of muscle control and spine stabilization allows your body to recover from chronic low back pain².

View this video to learn more about chronic low back pain and how ReActiv8 works.

¹ Hebert, J. J., Koppenhaver, S. L., Magel, J. S. & Fritz, J. M. The relationship of transversus abdominis and lumbar multifidus activation and prognostic factors for clinical success with a stabilization exercise program: a cross-sectional study. Arch. Phys. Med. Rehabil. 91, 78–85 (2010).
² Costa, L. O. P. et al. Motor control exercise for chronic low back pain: a randomized placebo-controlled trial. Physical therapy 89, 1275–86 (2009).
³ Hides, J. A., Jull, G. A. & Richardson, C. A. Long-term effects of specific stabilizing exercises for first-episode low back pain. Spine 26, E243–8 (2001).

Clinical Literature:

ReActiv8-A Clinical Trial

The ReActiv8-A clinical trial is an international, multi-centre, prospective single arm clinical trial with up to 96 subjects at sites in Australia and Europe. Outcome measures for the ReActiv8-A clinical trial are assessed at a three-month endpoint after activation of stimulation and compared to baseline prior to implant. Results from the first 47 patients enrolled in the ReActiv8-A Clinical Trial supported the CE-Marking of the system. Further details can be obtained at: https://clinicaltrials.gov/ct2/show/NCT01985230

ReActiv8-B Clinical Trial

The ReActiv8-B Clinical Trial is an international, multi-center, prospective randomized sham controlled blinded trial with one-way crossover, conducted under an Investigational Device Exemption (IDE). The statistical design of the Clinical Trial requires data from the pivotal cohort of 128 randomized subjects at the 120-day primary outcome assessment visit.

The primary efficacy endpoint of the ReActiv8-B Clinical Trial is a comparison of responder rates between the treatment and control arms. The Clinical Trial will be considered a success if there is a statistically significant difference in responder rates between the treatment and control arms. The Clinical Trial, if successful, will provide what is referred to as Level 1 Evidence of safety and efficacy of ReActiv8, which may be used to support applications for favourable reimbursement in the USA. Further details can be obtained at: https://clinicaltrials.gov/show/NCT02577354

ReActiv8-A Results-Summary

The ReActiv8-A international multicenter clinical trial (N=47) shows clinically important and statistically significant improvement in low back pain¹‎,‎ disability²‎ and‎ quality‎ of‎ life³‎ at‎ 90‎ days,‎ 180‎ days‎ and‎ 1‎ year.

Forty-seven subjects were implanted in 9 centers in Europe and Australia. Key inclusion criteria included disabling Chronic Low Back Pain (CLBP, NRS ≥6 and ≤9) despite a minimum of 90 days of medical management including at least physical therapy and drugs, no identifiable spine pathology as a likely cause, no prior spine surgery, and no indications for spine surgery or spinal cord stimulation. Subjects were asked to administer stimulation in two 30 minute sessions per day for a minimum of 90 days.

At‎ enrolment,‎ average‎ duration‎ of‎ low‎ back‎ pain‎ was‎ 14±‎ 10‎ years;‎ average‎ age‎ was‎ 44±‎ 11‎ years‎,‎ and‎ 55%‎ of‎ subjects‎ were‎ female‎ and‎ 45%‎ male.‎ The‎ majority‎ of‎ subjects‎ (70%)‎ were‎ regularly‎ taking‎ opioids‎ at‎ baseline.‎ All‎ reported‎ improvements‎ were‎ significant‎ (p<0.001).

Conclusion

Electrical stimulation to reactivate the lumbar multifidus appears to be an effective treatment option for subjects with refractory CLBP and no indications for surgery.

¹ Dworkin, R.H. et al (2008). Interpreting the clinical importance of treatment outcomes in chronic pain clinical trials: IMMPACT recommendations. The Journal of Pain, 9(2), 105-21.
² Ostelo, R. W. et al (2008). Interpreting change scores for pain and functional status in low back pain: towards international consensus regarding minimal important change. Spine, 33(1 ), 90-4.
³ Soer, R. et al (2012). Clinimetric properties of the EuroQol-50 in patients with chronic low back pain. Spine Journal, 12(11 ), 1035-1039.