Podiatric physicians continue to gain new tools and technologies to improve lower extremity care. This author gets the input of experts on recent and emerging innovations in areas including surgical advances, wound care and antifungals.
Emerging advances in technology in 2014 include two new antifungals, a device to help detect neuropathy, improved wound dressings, painless harvesting of epidermal skin grafts, a skin substitute, a total ankle implant and a device to augment bone marrow stimulation.
Hyalomatrix® (Anika Therapeutics). An innovative wound dressing utilizes hyaluronic acid to provide a three-dimensional scaffold to promote cellular invasion and capillary growth.
Adam Landsman, DPM, PhD, notes the Hyalomatrix contains a fibrous form of hyaluronic acid bound to a semi-permeable layer of silicone. He says the hyaluronic acid component acts as a biodegradable scaffold for proliferating cells and capillary growth while the silicone membrane preserves moisture and protects the wound.
“In this way, it is a great alternative to the much more expensive products composed of animal collagen and silicone,” says Dr. Landsman, an Assistant Professor of Surgery at Harvard Medical School.
The manufacturer Anika Therapeutics says Hyalomatrix is a bilayered, sterile, flexible wound dressing composed of a non-woven pad made entirely of HYAFF®, a benzyl ester of hyaluronic acid. When the newly formed dermal matrix integrates the HYAFF-based material, the company says a well-vascularized granulation tissue forms to facilitate wound closure via spontaneous re-epithelialization or a suitable dermal layer for skin grafting.
Anika says Hyalomatrix is indicated to help manage the following wounds: partial and full-thickness wounds; second-degree burns; pressure ulcers; venous ulcers; diabetic ulcers; chronic vascular ulcers; tunneled/undetermined wounds; surgical wounds; trauma wounds; and draining wounds.
Dr. Landsman cites “outstanding” preliminary results in the last few months of use, saying he has seen “obvious increases” in the development of granulation tissue after just two weeks of application. Similar to using the more expensive biologics, he says one peels away the silicone layer once separation has occurred.
Dr. Landsman notes one can reapply Hyalomatrix as frequently as twice per week if necessary. Alternatively, if the wound is clean, he says the dressing can stay in place for up to two weeks. Since the dressing can remain in place for an extended period, he does not recommend using it on highly contaminated or infected wounds without first pretreating to bring the infection or contamination under control.
Hydrofera Blue® Ready (Hollister Inc). When managing wound bioburden is a concern, an innovative spin on an established technology might be the answer for physicians. The new Hydrofera Blue Ready foam uses methylene blue and gentian violet to provide broad-spectrum antibacterial protection, according to the manufacturer Hollister Inc.
Eric Lullove, DPM, CWS, says the polyurethane foam can absorb moderate to heavy exudate. He maintains that the new foam dressing does not pull away from the wound and does not lead to maceration.
“For the majority of lower extremity wounds, (Hydrofera Blue Ready is) a great product,” says Dr. Lullove, who is in private practice in Boca Raton, Fla.
Dr. Lullove adds that the Hydrofera Blue Ready is easier to use than other foams in the same class and one can leave it in place for up to seven days. Dr. Lullove comments that using Endoform to reduce elevated matrix metalloproteinases and covering with Hydrofera Blue Ready foam to reduce bioburden and absorb exudate works well for his patients with venous leg ulcers and diabetic foot ulcers. Hollister notes that there is no hydration or secondary dressing required with the Hydrofera Blue Ready. The waterproof barrier keeps away moisture and bacteria, and the company adds that the dressing is non-cytotoxic and less expensive than most silver dressings.
“From my perspective, (Hydrofera Blue Ready) is taking a proven technology and reinventing the wheel, making it more user-friendly and more versatile as to how it can be used,” says Dr. Lullove.
Enluxtra™ Self-Adaptive Wound Dressing (OSNovative Systems). Wound conditions may be constantly changing but a new wound dressing reportedly can adapt to such changes and facilitate healing.
Enluxtra Self-Adaptive Wound Dressing dynamically balances the evolving moist wound environment, notes the manufacturer OSNovative Systems. The company says the dressing provides hydration or absorption depending on the needs of the wound and periwound skin. As the company notes, dry areas of the wound stay properly hydrated, the dressing absorbs and locks in fluid from exuding areas, and protects periwound skin from maceration.
Alexander Reyzelman, DPM, FACFAS, cites the Enluxtra as a “smart dressing” that one can use in various wounds such as diabetic foot ulcers, pressure ulcers, venous leg ulcers, and postoperative wounds. He notes an advantage in that the dressing can absorb a large amount of exudate and trap it within the dressing. Dr. Reyzelman says this allows autolytic debridement to occur by providing the appropriate wound environment.
“I have been impressed by the amount of exudate (Enluxtra) can absorb in the highly exudative venous leg ulcers. I’ve also been impressed with how it can be placed on a dry wound and keep the wound base moist,” says Dr. Reyzelman, an Associate Professor in the Department of Medicine at the California School of Podiatric Medicine at Samuel Merritt University in Oakland.
In addition, Dr. Reyzelman, the Co-Director of the UCSF Center for Limb Preservation, says Enluxtra can adapt to the various wound types such as highly exudative or minimally exudative wounds, and allow the wounds to progress to healing. He notes the dressing comes in various sizes and one can use it under compression or on surgical incisions in the operating room.
Key Advances In Podiatric Surgery
BioCartilage® (Arthrex). Osteochondral lesions of the talus can commonly occur after ankle sprains and one of the tried and true treatments for such lesions is bone marrow stimulation. A new micronized cartilage matrix can augment the bone marrow stimulation of osteochondral lesions of the talus.
Calling the BioCartilage “an excellent adjunct to bone marrow stimulation,” Alan Catanzariti, DPM, FACFAS, notes the product has an extracellular matrix native to articular cartilage including key components such as type II collagen, proteoglycans and additional cartilaginous growth factors. The manufacturer Arthrex notes that BioCartilage serves as a scaffold over a microfractured defect to provide a tissue network that can potentially signal autologous cellular interactions and improve the degree and quality of tissue healing within a properly prepared articular cartilage defect. Dr. Catanzariti adds that bone marrow elements will travel through the microfracture holes and interact with the scaffold instead of creating their own fibrin scaffold as typically happens with a bone marrow stimulation procedure.
Dr. Catanzariti uses the BioCartilage as an adjunct to bone marrow stimulation for virtually every osteochondral lesion of the talus less than 15 mm in diameter and cites encouraging preliminary results.
BioCartilage has several advantages relative to other biologic adjuncts such as platelet rich plasma, concentrated bone marrow aspiration or particulate juvenile cartilage for augmenting repair and replacement of osteochondral lesions of the talus, according to Dr. Catanzariti, the Director of Residency Training at the Western Pennsylvania Hospital in Pittsburgh. He says the small particle size improves BioCartilage’s injectable nature after one mixes it with an autologous blood solution, allowing easier delivery to the defect site. In addition, Dr. Catanzariti says the small particle size also increases the surface area, providing attachment sites for the patient’s bone marrow cells. Furthermore, the price of BioCartilage is approximately $770 per 1 cc, which Dr. Catanzariti notes is relatively inexpensive in comparison to other biologic adjuncts that surgeons use to treat osteochondral lesions of the talus.
Zimmer® Trabecular Metal™ Total Ankle (Zimmer). An emerging total ankle implant utilizes a lateral transfibular approach that may help reduce the incidence of postoperative infection. The manufacturer Zimmer notes its Zimmer Trabecular Metal Total Ankle’s lateral approach avoids stressing neurovascular structures and disrupting angiosomes. The company says the lateral approach allows full visualization of the anatomic center of rotation.
Lawrence DiDomenico, DPM, FACFAS, notes that the Trabecular Metal Total Ankle is the only FDA-approved ankle implant that offers a lateral approach. Most of the patients he sees for possible ankle replacement surgery are post-traumatic. Dr. DiDomenico says some of these patients have had either an open fracture or previous surgery, leading to soft tissue complications.
“In scenarios such as this, a lateral approach is very desirable,” says Dr. DiDomenico, the Section Chief of the Department of Podiatry at St. Elizabeth Hospital in Youngstown, Ohio.
Zimmer adds that the implant reproduces the ankle’s natural flexibility and motion, and features Prolong® Highly Crosslinked Polyethylene. The semi-constrained Zimmer device provides joint mobility by restoring alignment, reducing pain and preserving the flexion/extension movement within the ankle joint, according to the company. The three implant components include a talar component, tibial base component and modular tibial articular surface, according to Zimmer. It also cites the benefit of six implant sizes in anatomic configurations with variable radii of curvature in proportion to implant size as in the natural ankle.
Dr. DiDomenico says with the Trabecular Metal Total Ankle, joint resection is similar to a normal joint. The bone loss is relatively small and he notes the implant offers a highly cross-linked polyethylene, which has a fivefold decrease in wear in comparison to the use of conventional polyethylene.
A Closer Look At Emerging Antifungals
Luzu® (Valeant Pharmaceuticals). Podiatrists now have a new topical option for the treatment of tinea pedis.
Tracey Vlahovic, DPM, cites luliconazole cream 1% (Luzu) as an innovative topical azole. A principal investigator on the phase 3 clinical trial, she notes the product has garnered FDA approval for interdigital tinea pedis for once-a-day application as part of a two-week treatment regimen. Dr. Vlahovic points out that Luzu recently had its launch in the United States after being available for several years in Japan.
The manufacturer Valeant Pharmaceuticals cites two pivotal studies with the primary endpoint defined as complete clearance four weeks post-treatment. In the first study, 26 percent of patients treated with Luzu were completely cleared of tinea pedis in comparison to only 2 percent of people treated with the vehicle. The second study showed 14 percent of people treated with Luzu had completely cleared in comparison to only 3 percent of those treated with the vehicle.
Kerydin (Anacor Pharmaceuticals). A new class of topical antifungal for onychomycosis may debut on the market soon. Tavaborole (Kerydin) was the subject of a New Drug Application review from the Food and Drug Administration last fall and its Prescription Drug User Fee Act goal date is July 29, according to the manufacturer Anacor Pharmaceuticals.
The company notes that Kerydin has a boron-based mechanism of action and has enhanced nail penetration properties that deliver the compound to the nail bed.
Dr. Vlahovic notes clinical trials for the product focused on older patients with advanced nail disease who had positive results with Kerydin. In two phase 3 clinical trials, Anacor Pharmaceuticals says Kerydin achieved a high degree of statistical significance on all primary and secondary endpoints. The primary endpoint was complete cure (completely clear nail and negative mycology) of the target great toenail after 48 weeks of treatment, according to the company. About 600 patients with distal subungual onychomycosis participated in each study and applied either tavaborole solution or the vehicle to the target great toenail once daily for 48 weeks.
Dr. Vlahovic also notes that early in vitro data shows that one may use tavaborole in conjunction with nail polish.
“More research has to be done in this area but it is promising that our patients will be able to have the cosmesis covering of nail polish with the medicinal properties of Kerydin,” says Dr. Vlahovic, an Associate Professor at the Temple University School of Podiatric Medicine.
Can New Modalities Help Improve Healing In Wound Care?
CelluTome™ (KCI). With a new device, one may harvest epidermal skin grafts with little or no pain for the patient. The CelluTome produces a number of epidermal micrografts that are ready for immediate transfer onto a recipient site, notes the manufacturer KCI. Lee C. Rogers, DPM, notes that the system uses suction and heat for harvesting.
KCI says the CelluTome consistently harvests epidermis at the dermal-epidermal junction, including basal keratinocytes. The harvesting procedure raises uniform microdomes and the company adds that the micrografts harvested contain undamaged tissue, evidenced by the cells growing outward from the micrograft edge.
When using the CelluTome device, Dr. Rogers notes that most patients will have no pain while others may experience a mild tugging or pulling. He says the CelluTome causes about 100 tiny blisters that one can subsequently cut with a disposable blade and transfer to a Tegaderm dressing. The clinician can then transfer the Tegaderm and islands of epidermis to the foot, notes Dr. Rogers, the Medical Director of the Amputation Prevention Center at the Sherman Oaks Hospital in Sherman Oaks, Calif.
“CelluTome is a novel device that allows a doctor to harvest a skin graft in the clinic (as opposed to the OR) without anesthesia. It has the potential to change the landscape in diabetic foot ulcer treatment,” says Dr. Rogers.
PriMatrix Ag (TEI Biosciences). The antimicrobial power of silver fuels an emerging skin substitute.
Kazu Suzuki, DPM, CWS, points out that PriMatrix Ag is the only skin substitute on the market today with built-in antimicrobial ionic silver. As with any other silver-based products, he says ionic silver offers broad spectrum antimicrobial activity, covering both gram positive and negative organisms as well as resistant bacteria such as methicillin-resistant Staph aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). Dr. Suzuki has been using PriMatrix Ag on diabetic foot ulcers, venous leg ulcers and surgical wounds. Dr. Suzuki notes the modality’s ionic silver prevents wound infection while the graft is incorporating within the healing wound.
“I found it to be highly useful in closing ‘difficult-to-heal’ wounds and chronic wounds that did not respond to basic wound care, consisting of sharp debridement and appropriate dressing application,” says Dr. Suzuki, the Medical Director of the Tower Wound Care Center at the Cedars-Sinai Medical Towers.
PriMatrix Ag is unique since it is rich in type 3 collagen, notes Dr. Suzuki. He emphasizes that type 3 collagen is the active collagen found in developing and healing tissues.
The scaffold comes in various sizes and in a dehydrated form with a three-year shelf life. Dr. Suzuki adds that it is pre-meshed or fenestrated, which simplifies the application process. He notes that the PriMatrix Ag has a good tensile strength so one can suture it. Dr. Suzuki also points out that he often uses Mepitel (Molnlycke Health Care) or Steri-Strips (3M) to secure PriMatrix Ag over the wound.
The manufacturer TEI Biosciences notes that the proprietary manufacturing process for PriMatrix Ag preserves the natural dermal collagen fibers’ beneficial properties, generating a tissue matrix that is free of contaminants, artificial chemical crosslinks and denatured proteins. When one applies the modality to the wound, the scaffold’s purity minimizes detrimental foreign body inflammatory responses, according to the company.
Dr. Suzuki adds that Medicare and other insurance companies reimburse PriMatrix Ag with the Q4110 code and as a “high-tier” skin substitute product. He says the application codes are the CPT 15271-15278 series for “application of skin substitute graft.”
The product’s indications include pressure, diabetic and venous ulcers as well as second-degree burns, surgical wounds and traumatic wounds, according to Dr. Suzuki. He points out that these are much broader indications than the other skin substitutes, which are often limited to either diabetic foot ulcers and/or venous leg ulcers.
A New Advance In Detecting Diabetic Peripheral Neuropathy?
Electronic Tuning Fork (O’Brien Medical). Given the urgency of preventing limb loss in patients with diabetes, an emerging diagnostic device could prove to be beneficial in terms of prevention.
The 128-Hz Electronic Tuning Fork can reportedly detect patients at risk for diabetic neuropathy and limb loss, according to the manufacturer O’Brien Medical. The company says the new fork is an improvement over handheld tuning forks, which have limitations in terms of reproducibility and quantification of results. O’Brien Medical notes the Electronic Tuning Fork is a modern digital instrument calibrated to offer standardized, quantifiable results with improved accuracy and reproducibility. It says the device should be available for purchase late this year.
Tammer Elmarsafi, DPM, first used the Electronic Tuning Fork in January 2014. He began using it exclusively in his clinics but after reaching 30 patients, he started to use it for in-patient consultations and admissions as well.
Dr. Elmarsafi points out that there are only two methods to screen/test for peripheral neuropathy: the simple conventional tuning fork, and the more expensive and large biothesiometer, which is based on increasing increments of vibration. He notes the battery operated Electronic Tuning Fork combines the best of both tests and provides a digital readout that is easy to interpret.
The Electronic Tuning Fork provides the clinician with a numerical read in real time, which one can compare to a chart on the device that gives ranges correlating with the degree of neuropathy, according to Dr. Elmarsafi, a first-year resident in the Department of Podiatric Surgery at the MedStar Washington Hospital Center in Washington, D.C. For patients who are at high risk for neuropathy but have some level of vibratory sensation, he says one can use the numbers to track changes over time.
Dr. Elmarsafi notes no contraindications to using the Electronic Tuning Fork that are different from using a tuning fork or biothesiometer. He does cite the noise that the fork makes, saying this might be an auditory clue to the patient who has no sensation. However, Dr. Elmarsafi says clinicians can avoid this by placing the node on the patient while keeping the shaft perpendicular to the skin.
The Journal of the American Podiatric Medical Association recently published a proof of concept study on the Electronic Tuning Fork.1 The study focused on 55 patients and found that the sensitivity and specificity of neuropathy detection for the Electronic Tuning Fork were 0.953 and 0.761 respectively
“I think that the Electronic Tuning Fork is accurate, easy to use and a time saver,” says Dr. Elmarsafi. “I have put the (device) to the grind and have found it to be of clinical utility, and encourage others to further evaluate the Electronic Tuning Fork.”
1. O’Brien T, Karem J. An initial evaluation of a proof of concept 12-Hz electronic tuning fork in the detection of peripheral neuropathy. J Am Podiatr Med Assoc. 2014; 104(2):134-40.
Editor’s note: Dr. Suzuki discloses that he has received an honorarium from TEI Biosciences in the past 12 months.