Intended Purpose/Indication for ReActiv8

The ReActiv8 System is indicated for bilateral stimulation of the medial branch of the dorsal ramus as an aid in the management of mechanical chronic low back pain associated with multifidus muscle dysfunction, in adults who have failed therapy including pain medications and physical therapy and are not candidates for spine surgery.

Contraindications 

ReActiv8 is contraindicated for patients who are: 

• Unable to operate the system Impaired shoulder mobility limiting the ability to place the activator antenna over the IPG 
• Evidence of cognitive impairment that limits the patient’s ability to operate the device 

Unsuitable for ReActiv8 implant surgery, for reasons such as: 

• The patient has an active infection in the vicinity of the surgical site, or any systemic infection 
• The patient is on blood thinners and unable to be temporarily discontinued for the surgical procedure

Possible benefits of ReActiv8* 

The possible benefits associated with ReActiv8 include: 

• Reduction in the severity of your low back pain; 
• Improvement in your ability to handle regular daily activities (reduction of disability); and 
• Improvement in your quality of life. 

*For details related to the possible benefits of ReActiv8, refer to the ReActiv8 Summary of Safety and Clinical Performance (SSCP). A copy of the SSCP) can be viewed by searching the device brand name on the Eudamed website at https://ec.europa.eu/tools/eudamed, when it is available. A copy of the SSCP is also available at www.mainstaymedical.com/resources.

Electromagnetic Interference (EMI) – Electromagnetic interference from electrical or magnetic fields generated by equipment found in the home, work, medical or public environments may interact with or disrupt the function and operation of the ReActiv8 System. The ReActiv8 system includes features that provide a measure of protection from EMI, and most electrical devices and magnets encountered in a normal day are unlikely to affect the operation of the system. However, sources of strong EMI can result in the following effects:

• Serious patient injury or death, resulting from heating of the implanted components of the ReActiv8 system, leading to damage to surrounding tissue.
• Damage to implantable components, resulting in a loss of function that may require surgical replacement.
• Operational changes to the ReActiv8 IPG, causing it to turn Stimulation ON or OFF (particularly if the IPG is enabled for Magnet use), or to reset, resulting in loss of stimulation and requiring reprogramming.
• Use of non-implantable ReActiv8 system components adjacent to or stacked with other equipment should be avoided because it could result in improper operation. If such use is necessary, this equipment and the other equipment should be observed to verify that they are operating normally. 
• * There are no user replaceable cables with the ReActiv8 system. Use of accessories, transducers and cables other than those specified or provided by the manufacturer of this equipment could result in increased electromagnetic emissions or decreased electromagnetic immunity of this equipment and result in improper operation. 
• * Portable RF communications equipment (including peripherals such as antenna cables and external antennas) should be used no closer than 30 cm (12 inches) to any part of the ReActiv8 system, including cables specified by the manufacturer. Otherwise, degradation of the performance of this equipment could result. 

EMI from the following medical procedures or equipment may damage the device, interfere with device operation, or cause harm to the patient. If these procedures are required, follow the guidelines below.

Diathermy therapy – Safety of diathermy with an implanted ReActiv8 System has not been evaluated. Do not use short-wave diathermy, microwave diathermy, or therapeutic ultrasound diathermy (all now referred to as diathermy) on patients implanted with a ReActiv8. Energy from diathermy can be transferred through the implanted system and cause tissue damage at the location of the implanted leads, resulting in severe injury or death. 

Diathermy should not be used because it may damage the IPG components. This damage could result in loss of function, requiring additional surgery. Injury or damage can occur during diathermy treatment whether the system is turned on or off. All patients should be advised to inform their healthcare professionals that they should not be exposed to diathermy treatment. 

Magnetic resonance imaging (MRI) – MRI compatibility of the ReActiv8 system is conditional on imaging parameters. Refer to the ReActiv8 System Magnetic Resonance Imaging (MRI) Guidelines.

MRI Safety Information

Magnetic Resonance Imaging (MRI) 

The ReActiv8 Implantable Pulse Generator (IPG) and implantable leads are MR Conditional devices with demonstrated safety in the MR environment only within specified conditions.

Consult with your healthcare provider prior to an MR exam and inform MRI site personnel that they have an MR Conditional medical device during MR screening prior to the MR exam.

Refer to the document ReActiv8 System Magnetic Resonance Imaging (MRI) Guidelines for an up-to-date list of approved MR Conditional components, model numbers and required conditions (including patient preparation) for safe use in the MR Environment. Referring to this document prior to an MRI scan is mandatory.

Failure to follow these guidelines for MRI scans may result in severe patient injury and/or device malfunction.

Defibrillation/cardioversion – When a patient is in ventricular or atrial fibrillation, the first consideration is patient survival. External defibrillation or cardioversion can damage the ReActiv8 IPG. It may also cause induced currents in the leads that can injure the patient. Minimize the current flowing through the ReActiv8 system by following these guidelines: 

• If possible, program the ReActiv8 IPG Mode to OFF. 
• Position the defibrillator paddles as far from the ReActiv8 system as possible. 
• Position the defibrillation paddles perpendicular to the ReActiv8 lead path. 
• Use the lowest clinically appropriate energy output for defibrillation. 
• After defibrillation or cardioversion, verify proper device operation and perform a stimulation test. If an anomaly is detected, corrective actions may include lead repositioning or replacement and/or device reprogramming or replacement. 

Electrocautery and radio frequency (RF) ablation – Electro-surgery devices should not be used in close proximity to the ReActiv8 IPG or Lead(s). Contact between a lead and the electrosurgical instrument can cause direct stimulation of a nerve and can result in severe injury to the patient. Electro-surgery devices may also damage the lead or IPG and cause a loss of stimulation. 

If electrosurgical cautery or RF ablation cannot be avoided, observe the following precautions to minimize complications: 

1. Program the ReActiv8 IPG Mode to OFF. 
2. Avoid direct contact between the cautery equipment or ablation catheter and the implanted ReActiv8 IPG or Leads. 
3. Use a bipolar electro-cautery system if possible. 
4. Use short, intermittent bursts at the lowest possible energy levels. 
5. Verify proper operation of the ReActiv8 System and perform a stimulation test immediately following the procedure. If an anomaly is detected, corrective actions may include lead repositioning or replacement and/or device reprogramming or replacement. 

ReActiv8 interaction with other active implantable devices – Safety of the ReActiv8 System has not been evaluated when used in combination with active implantable devices (e.g., pacemaker, defibrillator, spinal cord stimulation). There may be undesirable interactions between the stimulation pulses of the ReActiv8 System and the other active implantable device. In the event of a patient requiring both a ReActiv8 System and an active implantable device, physicians involved with both devices (e.g., neurologist, neurosurgeon, cardiologist, cardiac surgeon) should discuss the possible interactions between the devices before surgery. 

Other

Case damage – If the ReActiv8 IPG case is pierced or ruptured, severe burns could result from exposure to battery chemicals. 

Precautions

• Do not crush, puncture, or burn the IPG – risk of explosion or fire.
• Do not incinerate or cremate the ReActiv8 IPG – risk of explosion.
• Do not reuse any implantable device or implantable accessory after exposure to body tissues or fluids because the functionality of the component cannot be guaranteed.
• Laptop computer battery maintenance or replacement should only be performed by authorised personnel.

Electromagnetic Interference (EMI) Guidelines

EMI from the following equipment is unlikely to affect the ReActiv8 System if the guidelines below are followed: 

• Computed tomographic X-ray (CT scan) – If the patient undergoes a CT scan procedure, turn the IPG Mode to OFF. After completing the procedure, restore the desired parameters. 
• High output ultrasound and lithotripsy – Program the ReActiv8 IPG Mode to OFF. The use of high output ultrasound devices, such as an electrohydraulic lithotriptor, may damage the electronic circuitry of an implanted IPG. If lithotripsy must be used, do not focus the energy near the IPG. 
• Electronic article surveillance (EAS) – EAS equipment such as retail theft prevention systems, as well as airport metal detectors may interfere with the ReActiv8 System. Advise patients to walk directly through an EAS system and not remain near an EAS system longer than necessary. 
• Radiation therapy – Ionizing radiation produced by high energy radiation sources, such as cobalt 60 or gamma radiation, can damage active implantable medical devices. The effect is cumulative and can vary from temporary modifications to irreversible damage, depending on dose rate and total radiation. Note that this effect may not be immediately detected. If radiation therapy is required, program the IPG to OFF and protect the implanted device with lead shielding. Verify IPG operation after exposure. If tissue near the implant site must be irradiated, IPG relocation should be considered. 
• Static magnetic fields – Avoid equipment or situations where there is a risk of exposure to static magnetic fields greater than 10 gauss or 1 mT. Sources of static magnetic fields include, but are not limited to, audio loudspeakers, magnetic badges, or magnetic therapy products. If patients cannot avoid magnetic fields, the Magnet Effect parameter should be programmed to None. 
• Bone growth stimulators – Safety has not been established for bone growth stimulators in patients who have a ReActiv8 System. If bone growth stimulators must be used, turn the ReActiv8 IPG Mode to OFF. Keep external magnetic field bone growth stimulator coils as far away from the IPG as possible. When using either an implantable or external bone growth stimulator, ensure that both the bone stimulator and the ReActiv8 System are working as intended. 
• Diagnostic ultrasound probes – Turn the ReActiv8 IPG Mode to OFF. Keep the probe away from the IPG. An average acoustic intensity of greater than 500 watts per meter squared should not be used. 
• Electrolysis – Safety has not been established for electrolysis therapy in patients who have a ReActiv8 System. If electrolysis must be used, turn the ReActiv8 IPG Mode to OFF. Keep the electrolysis wand as far away from the IPG as possible. 
• Electroconvulsive therapy (ECT) – Safety has not been established for ECT in patients who have a ReActiv8 System. Induced electrical currents may cause heating, especially al the lead electrode site, resulting in tissue damage. 
• Transcranial magnetic stimulation (TMS) – Safety has not been established for TMS in patients who have a ReActiv8 System. Induced electrical currents may cause heating, especially at the lead electrode site, resulting in tissue damage. 
• Externally-applied monitoring equipment – Externally-applied patient monitoring equipment, such as an ECG machine or Holter recorder, may detect ReActiv8 stimulation pulses. 
• Explosive or flammable gases – The Programmer and Activator are not certified for use in the presence of a flammable anaesthetic mixture with air or an oxygen or nitrous oxide rich environment. The consequences of using the programmer near flammable atmospheres are unknown. 
• Electromagnetic field devices – Exercise care or avoid the following equipment or environments which may affect normal operation of the ReActiv8 System due to strong magnetic, electrical and electromagnetic fields:
  • Antennas of ham radios should be kept at least 4 m (13 feet) away 

• Antennas of citizens band (CB) radios should be kept at least 2.5 m (8 feet) away 
• Cellular phones should be kept at least 1.5 m (5 feet) away 
• Wi-Fi® radio equipment should be kept 75 cm (30 inches) away 
• Bluetooth® radio equipment should be kept 20 cm (8 inches) away 
• Electric arc welding equipment 
• Electric induction heaters used in industry to bend plastic 
• Large electric motors or alternators 
• Electric steel furnaces 
• High-power amateur radio transmitters 
• High-voltage areas 
• Power amplifiers 
• Magnetic degaussing equipment 
• Magnets or other equipment that generates strong magnetic fields 
• Microwave communication transmitters 
• Perfusion systems 
• Resistance welders 
• Television and radio transmitting towers 

If it is suspected that equipment is interfering with ReActiv8, the following is recommended: 

1. Move away from the equipment or object. 
2. If possible, turn OFF the equipment or object. 
3. Then, if necessary, use the Magnet or Activator to disable stimulation. 
4. Inform the equipment owner or operator of the occurrence. 

If the above actions do not resolve the effects of the interference, or there is a suspected change after exposure to EMI, then the patient should contact their physician. 

If magnetic fields cannot be avoided, the Magnet Effect parameter should be programmed to None. 

Laser procedures – Turn the ReActiv8 IPG Mode to OFF. Keep the laser directed away from all components of ReActiv8. 

Electromagnetic interference (EMI) from household items 

Most household appliances and equipment that are working properly and grounded properly will not interfere with the ReActiv8 System. Many household items contain magnets or generate magnetic fields that are strong enough to activate the magnet switch inside the IPG, which can be programmed to start or stop therapy. 

If interference is suspected, instruct the patient to move away or turn off the household item.

The Mainstay Tunneler (Model TUN1) contains up to 0.26% cobalt, which exceeds the hazardous substance limit of 0.1% w/w. 

The implantation of ReActiv8 involves risks similar to those of peripheral nerve stimulators. In addition to risks commonly associated with surgery, implantation or use of ReActiv8 includes, but is not limited to, the following risks:

• Adverse Events (AEs) associated with the surgical procedure, including implant, revision, replacement and removal. 
• Acute or persistent pain including more pain than anticipated after surgery or worsened low back pain. 
• Accidental injury to adjacent tissues, e.g. piercing structures such as muscle, blood vessels or organs. 
• Infection, including local infection of the surgical site, systemic infection, and sepsis 
• Slow, abnormal, or inadequate wound healing including wound dehiscence (slow healing), which may require surgical repair. 
• Tissue reaction to the presence of the implanted device or materials in/on the implanted device such as response to residual material on device or an allergic response, e.g., previously unknown nickel or titanium allergy. Reaction may be local or systemic. 
• Nerve irritation, impingement, or damage, including that resulting from mechanical presence of device, exposure to electricity including electrical stimulation, or migration of the leads, suture sleeve or IPG. This may lead to pain, paralysis, sensory deficits or changes to bowel, bladder, or reproductive function. 
• Device extrusion. 
• Erosion, threatened erosion, or fistula formation in skin overlying device components. 
• Excessive fibrotic tissue growth. 
• Hematoma, seroma, cyst or swelling. 
• Acute or persistent pain including worsened low back pain and/or pain and discomfort due to presence of the device. 
• Undesired sensations such as uncomfortable paraesthesia, numbness, vibration, pressure, prickling, or uncomfortable contraction of the multifidus. 
• Overstimulation of tissue, resulting in symptoms such as painful muscle contraction, paraesthesia, jolts, or shocks. In addition, injuries that occur as a consequence of stimulation, e.g., accidents that occur as a result of being startled. 
• Tissue damage due to mechanical presence of device, or exposure to electricity including electrical stimulation. 
• Contraction of muscles other than the target muscle(s). 
• Muscle fatigue, spasm, or injury. 
• Stiffness, including restricted motion due to adhesions to the device. 
• Inability to deliver stimulation, including inadequate doses of stimulation. Causes include lead migration, device malfunction or exposure to electromagnetic fields, e.g., security screening devices. 
• Undesired electrical stimulation. 
• Inability to stop therapy, with possible sequelae such as anxiety, restriction of movement, pain, muscle fatigue, postural changes, difficulty in walking, sitting or physical activity. 
• Accidents, injuries, body movements, body positions or biological process which lead to device complications. Examples include a fall which may cause damage to the IPG; sit-ups or severe coughing leading to migration of the lead; or fracture of bones leading to device migration or damage.
• Patients may also undergo medical and/or surgical intervention (such as revision or explant) to treat the issues identified above.

Target Population

ReActiv8 is not suitable for every patient with chronic low back pain. When selecting candidates for ReActiv8, consider the following:

• Chronic low back pain despite medical management and attempting at least one course of physical therapy.
• Able to operate the system.

The safety and effectiveness of the ReActiv8 system has not been established for:

• Pregnant women (including effects on a foetus, or during childbirth)
• Paediatric use (patients under the age of 18)
• Patients with worse leg pain than back pain
• Patients with radiculopathy below the knee

Manufacturer’s name and address

Mainstay Medical Limited

Clonmel House,
Forster Way,
Swords, Co. Dublin, K67F2K3
Ireland