Surgical Implant Schematic

Image Courtesy of Ehrensberger et al. 



Garwood received approval of its patent application on wound care in December, 2016. Our bone regeneration patent has been filed. We have exclusive licensing agreements with the University at Buffalo’s technology for the eradication of biofilms on implants (also approved in December, 2016), as well as its ion-sensitive pH sensor and cellular-level infrared (temperature) sensor technologies, covered by granted patents. The team members have developed and commercialized many other devices and have the in house competence to develop and launch leading edge products. The Garwood device technologies have attracted significant interest for active involvement from health care providers. The Garwood team has the experience and capability to expand a direct distribution model or to partner with an established sales channel.

Photo 1Design

Utilizing supercomputer modelling and rational product design, GMD is committed to improving existing form-factors, electro-stimulation treatments, monitoring and high-throughput data analysis. Over time, this logically leads to improved protocols, positively impacting the efficiency and

Energy Delivery Challenges

Batteries: The successful application of low levels of electrical power to treat clinical conditions traditionally includes a battery or a power cord. Despite significant advances in battery technology, serious issues remain: sterilization, charging, discharge, recharging and replacement. In some applications, implanted batteries require surgery to replace a discharged battery; pacemakers every ten years. A re-useable battery has to be engineered to withstand sterilization and cleaning requirements, which limits cleaning methods or the effectiveness of charging. The size, weight and shape of the battery can also influence the medical device form factor to the detriment of treatment.

Cords: Electrical power cords are used in many external devices, but this “tethers” the patient while they are being treated, thus reducing mobility, leading to patient reluctance and compliance issues. Power cords can be a trip or fall hazard, become tangled with other items and are a source of contamination and infection. Power cords can mechanically and electrically fail at their connections and within the length of the cord.

GMD Solution: No cord or battery, reducing weight, limiting pressure points, increasing mobility, compliance and sustained treatment.

Wound Healing

Background: Nine million people in American suffer from chronic wounds. Others have trauma or surgical wounds. Electrical stimulation to increase the rate of healing is an established and proven methodology. Patients with slow to heal surgical incisions, diabetic ulcers, pressure ulcers and similar conditions that last over 30 days, frequently involve infection, pain and restrictions on activity. These have all been successfully treated with electrical stimulation, but currently, treatment requires expensive, heavy equipment with a power cord and clinician intervention. These constraints lead to artificially limited treatments, due to costs and reimbursement rates, which can lead to the impression that electrical stimulation is not fully effective.

GMD Solution: Our electronic bandage is patient-administered, and in the second generation, will offer the clinician the ability to remotely program the device, while monitoring the patient, and benefiting from having de-identified patient data analyzed by bioinformatics software, to improve protocols over time.

Triage remotely: The ability to remotely monitor the state of wound healing allows clinicians to respond more efficiently and provide targeted levels of care. Examples: patients with draining wounds need frequent visits, those with pressure sores may not keep the ulcer unloaded, patients with diabetic ulcers are not always aware of the state of the wound, and lastly, dressings do not need to be disturbed as frequently when wounds are healing well.

Orthopaedic Implant Infections: 20% failure to re-implant

Background: In America, orthopaedic implant infections rates average 2.4%. In 2020, knee and hip joint replacements will exceed 2,000,000 while implant infections in those joints alone are expected to be 50,000 or more, with 10,000 patients never having a successful revision surgery. Those 10,000 patients suffer one of several unappealing results: the loss of a limb, living with spacers, no joint at all or a fused joint for the balance of their lives. In some cases, the infection leads to death.

Procedure: Orthopaedic implant infections are very difficult to treat. Antibiotics are used, but some bacteria have developed resistance to an array of known pharmaceuticals. The bacteria form a bio-film on the implant that is difficult to break down. The vast majority of patients with a diagnosed peri-prosthetic implant infection will have the joint removed, bone debrided, antibiotic loaded spacer inserted, four weeks of IV antibiotics, and a six to eight week waiting period to be certain the infection is gone. Because the infection may have required the removal of bone and other tissue, successful replacement surgery is achieved in (only) approximately 80% of patients, after 4.2 months on average before the replacement orthopaedic implant operation can occur.

GMD Solution: Utilize a biofilm eradication technology licensed exclusively from the University at Buffalo. Ehrensberger et al have demonstrated using Cathodic Voltage Controlled Electrical Stimulation (CVCES) that the biofilm can be broken down such that bacteria is “visible” to the immune system, and susceptible to the drugs and the infection can be eradicated. Their studies have shown that the application of constant cathodic voltage of 1.8V to commercially pure titanium for one hour significantly reduces MRSA viability. The stimulation elicits antimicrobial activity against the bacteria on the implant and in surrounding bone tissue. The researchers are confirming through further research the expectation that the stimulation will also work on other implanted metals.

The CVCES technology could be applied at surgery, by applying treatment directly to the implant. The Garwood plan is to include the externally powered stimulator probes within the implanted orthopaedic device (joint arthroplasty or spine fixator) so that it can be energized prophylactically after surgery, or in the future if there is any suspicion of infection, eradicating the biofilm and allowing control of infection. One particular example of a metallic implant, prone to infection is an osseo-integrated prosthesis for amputees, the implant passes the dermis allowing infection to track into the bone.

Photo2Bone Regeneration

Background: When bone is loaded, as occurs through normal activity there is at the cellular level a piezoelectric effect, a small current is generated. To aid the body in regenerating bone and achieving fusion bone stimulator Regeneration technology aims to create the same effect. For patients with fractures and micro motion at the implant site, where the bone does not heal there are significant restrictions to activity, with risks of deterioration of other aspects of health, this is often in combination with severe pain.

There are both implanted and externally worn electrical stimulator devices available that have a demonstrated effectiveness in promoting bone fusion. Internal or implanted devices require surgery for placement of the bone stimulator that includes a battery. Note the insertion of the stimulator is an additional surgery after placement of the spine or fracture fixation device. The externally worn devices and the nature of the electrical stimulation do not have the same targeted affect, they have been most successful for patients who have had a Posterior Lateral Interbody Fusion (PLIF) because the external stimulator can be worn in close proximity to the bone fusion site. Externally worn devices require either a power lead or a battery and have to be worn in the correct position for sustained periods. The bone healing success rate is limited by the nature of the battery, power leads and the patient wearing the device correctly (position) for an adequate length of time.

GMD Solution: The Garwood device removes the need for a relatively heavy and bulky battery and allows the incorporation of sensors to confirm duration of use is valuable. The external device would be stimulating an implantable stimulator that could be incorporated prophylactically adjacent to or integrated into the implant at manufacture.

The Garwood bone stimulator could be used in the presence of infection, which is presently a contra-indication for the use of bone stimulators. Different treatment modalities of biofilm eradication and bone stimulation could be programmed for different stages of healing.

Other Notes: It is important to remember for chronic wound healing, non-fusion and bone infection that the patients rarely have single isolated disease states. It is known that there are frequently other risk factors including diabetes, obesity, neuropathy, alcoholism and patients who smoke.

Also noteworthy is the fact that the GMD patents-pending electronics platform is the basis for all three generations of devices being developed, and that much of the development focus for all three devices will be run in parallel and also consecutively, as refinements, miniaturization and features are added.