From low-level light therapy to hyperbaric oxygen therapy, technological advances in pain management for animal patients are a boon to veterinary practice.
Today’s veterinary technology offers unique opportunities for enhancing pain management protocols, and forming comprehensive multimodal approaches to pain. Clients are increasingly concerned about the immediate and long-term effects of pharmaceutical medications – these concerns, sometimes founded (or unfounded) by “Dr. Google” have led to an increased pursuit of therapies traditionally labeled as complementary or alternative. As a modern veterinarian, you can improve patient care plans and client trust by becoming familiar with and using these tools. In this article, we will provide a brief overview of several of the most commonly used integrative pain management tools in veterinary medicine today.
1. Low-level light (LLT) therapy/ laser therapy/ photobiomodulation
The word “laser” stands for “light amplification by stimulated emission of radiation”. Therapeutic laser therapy has been established for decades in the human field. Veterinarians should be cognizant of the difference between a veterinary therapeutic laser and a light emitting diode (LED), which can easily be purchased online at a relatively low cost. LEDs utilize a broader range of wavelengths; therapeutic laser therapy typically utilizes wavelengths in the 600 nm to 1070 nm range, which allows for deeper tissue penetration.1
Veterinary therapeutic laser therapy units (typically Class 3-4 lasers) can vary in a number of ways, including wavelength, power density, pulse structure and even polarization.1 Additional parameters can include options or exact settings for exotic animals versus small animals versus large animals.
This modality is unique in that veterinary technicians can easily perform the therapy by utilizing preset therapeutic settings – these settings may include such labels as “intervertebral disc disease”, “wound” or “chronic inflammation”. The average time for a complete laser therapy session will depend on the number of points utilized, as well as the strength of the laser to deliver “x” number of Joules per time unit – the average time can range from about four to 15 minutes total.
This modality can be utilized for several purposes, including but not limited to:1
- Wound healing – including chronic or acute skin conditions or post-operative incision sites
- Decreasing pain and inflammation
- Spinal cord or neurological injury2
- Post-dental cleanings and procedures
- Preventative maintenance against sports-related injuries for agility dogs.
Evidence for pain reduction has been demonstrated in several studies, including one in which laser-treated post-operative tibial plateau leveling osteotomy (TPLO) patients demonstrated greater healing and significantly improved peak vertical force analysis versus their untreated counterparts.3 Significant gait improvements were noted in another study that compared laser treated post-operative TPLO patients versus untreated.4 Human literature has also noted a reduction in the pain associated with knee osteoarthritis following treatment with high-intensity laser therapy. 5
How it works
LLT functions in several ways, including:
- Increasing adenosine triphosphate (ATP) production1
- Altering reactive oxygen species1
- Modulating level of cytokines1
- Stimulating the immune system1
- Stimulating neurogenesis1
The North American Association for Photobiomodulation Therapy (NAALT) offers you the opportunity to remain up to date on the latest research and more. Examples of companies that offer a variety of laser therapies are Companion, Cutting Edge and Respond.
2. Regenerative medicine/ stem cell therapy
Regenerative medicine involves the harvesting and utilization of the body’s cells in order to treat diseases. Results have been controversial. This author will examine one main subset of regenerative veterinary medicine – stem cell therapy. Other therapies in this arena may include “platelet rich plasma” (PRP) or platelet injections, or “plasma rich in growth factors” (PRGF) injections.
Advanced veterinary training and an intimate knowledge of anatomy is necessary for the utilization of this technology. This procedure should be performed by veterinary professionals.
In small animal medicine, stem cell therapy is typically utilized for orthopedic conditions, such as osteoarthritis or cartilage degradation in long bone joints. In a 2018 study examining over 200 stem cell-treated canine patients, 90% of dogs demonstrated marked improvement in mobility, and daily activity.6 However, it is interesting to note that the use of regenerative medicine has not been limited to degenerative orthopedic conditions. A recent 2019 study analyzing the use of mesenchymal stem cells to treat keratoconjunctivitis sicca (KCS) demonstrated a significant decrease in expression levels of such inflammatory markers as CD4, IL-6, IL-1 and more.7
How it works
Mesenchymal stem cells (MSC) can be utilized for cartilage regeneration in animals.8,9 These cells are specifically selected due to their ability to take on the specific “morphophysiological aspects” of the cells around them, or overall plasticity.10 Cartilage regeneration is thought to be produced via:8
- Recruitment of endogenous cells
- Differentiation into chondrocytes
- Secretion of trophic factors for chondroprotection and immunosuppression.
Interestingly, the harvesting of mesenchymal stem cells can be performed at a myriad of locations in the small animal, including but not limited to the umbilical cord, muscle, fat pads, synovial fluid, adipose tissue and bone marrow.8 Following selection and harvesting of the cells, they are typically transplanted intra-articularly.9 Within the equine world, stem cell therapy studies have demonstrated improvements following injections into tendons and ligaments.11,12
The North American Veterinary Regenerative Medicine Association (navrma.org) offers readers the latest research and developments of this tool.
3. Pulsed electromagnetic field (PEMF) therapy
This is a form of electrotherapy that utilizes electromagnetic waveforms to treat tissues.13PEMF therapy can differ in a number of ways – including but not limited to the strength of magnetic fields (measured in units of Gauss), pulse width and pulse frequency, as well as targeted or non-targeted devices.13
Targeted PEMF therapy devices can be sold directly to veterinary clients. This can empower them with the ability to treat their pets from home.
PEMF can be utilized for conditions such as edema, bone healing, wound healing, acute and chronic pain, as well as osteoarthritis and general inflammatory conditions.13 Interestingly, this is one modality that has been approved by the FDA to treat conditions like post-operative pain as well as non-union fractures.13 In human medicine, this modality can be covered under Medicare and Medicaid.
Research demonstrating effective pain control with this therapy abounds in today’s literature. One study demonstrated superior pain control in osteoarthritic dogs using a non-targeted PEMF device, as compared to treatment with Firocoxib (a non-steroidal anti-inflammatory).14 Given this result, it is not surprising that PEMF devices have been advertised as “non-pharmaceutical anti-inflammatory devices or “NPAIDs”.13 Significant pain control with PEMF therapy has also been established in human literature; daily targeted PEMF treatment of human subjects following breast surgery resulted in significant pain reduction and reduced use of pharmaceutical pain medications.15
How it works
Targeted PEMF influences the nitric oxide (NO) molecules within the body, leading to reduced levels in inflammation. Other researched methods of action include the increased presence of heat shock proteins, affected cell membrane adenosine receptor expression, and more.13
This author would advise veterinarians to be diligent in utilizing PEMF devices that demonstrate research-based evidence in the veterinary field, since a plethora of PEMF and PEMF-like devices can be found online. More information on this category of products can be found at Respond Systems (respondsystems.com) as well as Assisi Animal Health (assisianimalhealth.com).
4. Hyperbaric oxygen therapy (HBOT)
Hyperbaric oxygen therapy involves breathing 100% oxygen under the presence of increased atmospheric pressure.16Literature on this modality can be found in both human and veterinary journals. Unlike the previously mentioned modalities, HBOT requires significant financial investment and safety precautions in order to avoid explosions, given the high concentrations of oxygen required.17
HBOT is typically practiced as an adjunctive therapy. Conditions that can be addressed with this therapy include but are not limited to:16
- Wound healing16
- Carbon monoxide poisoning16
- Severe inflammation cases – such as sepsis, snake envenomation, ischemia, encephalitis and more18
How it works
Hyperbaric oxygen therapy targets molecular mediators of inflammation, including cytokines, nitric oxide (NO) and growth factors.16 This leads to decreased edema and stimulation of angiogenesis, as well as recruitment of macrophages and more.16 These mechanisms of action can be especially groundbreaking in any clinical arena of decreased or lowered oxygenation within the body. For example, one study demonstrated that HBOT improved neurological outcomes following cardiac arrest and resuscitation.19
Additional research articles and information can be found at the Veterinary Hyperbaric Medicine Society website (vhbot.org).
Modern veterinary technology offers a range of opportunities for multimodal pain management plans. Both human and veterinary literature has provided research-based evidence for the technologies discussed in this article. However, more research is necessary to elevate and understand the strength and reach of these therapies.
* this article was peer reviewed
1Chung, H, et al. “The Nuts and Bolts of Low-level Laser (Light) Therapy.” Ann Biomed Eng. Vol. 40. (2)2012.
2Draper, WE, et al. “Low-level laser therapy reduces time to ambulation in dogs after hemilaminectomy: a preliminary study.” Journal of Small Animal Practice. Vol. 53. 2012.
3Rogatko, CP, et al. “Preoperative low level laser therapy in dogs undergoing tibial plateau levelling osteotomy: a blinded, prospective, randomized clinical trial.” Vet Comp Orthop Traumatol, 30 (1): 46-53.
4Renwick, SM, et al. “Influence of class IV laser therapy on the outcomes of tibial plateau leveling osteotomy in dogs.” 47 (4): 5050 – 515. Vet Surg. 2018.
5Wyszynska, J, et al. “Efficacy of high intensity laser therapy in treating knee osteoarthritis: a first systematic review.” Photomedicine and Laser Surgery, Vol 36 (7). 2018.
6Shah, K, et al. “Outcome of allogeneic adult stem cell therapy in dogs suffering from osteoarthritis and other joint defects.” Stem Cells International Volume. 2018.
7Sgrignoli, MR, et al. “Reduction in the inflammatory markers CD4, IL1, IL-6, and TNFalpha in dogs with keratoconjunctivitis sicca treated topically with mesenchymal stem cells.” Vol 31 (39), 101-525. 2019.
8Sasaki A, et al. “Mesenchymal stem cells for cartilage regeneration in dogs.” World Journal of Stem Cells, 26 11 (5): 254-269. 2019
9Kriston-Pal, E, et al. “Characterization and therapeutic application of canine adipose mesenchymal stem cells to treat elbow osteoarthritis.” Canadian Journal of Veterinary Research. 81 (1): 73-78. 2017.
10Markoski, MM. “Advances in the Use of Stem Cells in Veterinary Medicine: From Basic Research to Clinical Practice.” Scientifica. 2016.
11Godwin, EE, et al. “Implantation of bone marrow-derived mesenchymal stem cells demonstrates improved outcome in horses with overstrain injury of the superficial digital flexor tendon.” Equine Vet J. 44(1):25-32. 2012.
12Beerts, C. et al. “Tenogenically induced allogeneic peripheral blood mesenchymal stem cells in allogeneic platelet-rich plasma: 2-year follow-up after tendon or ligament treatment in horses.” Front Vet Sci. (4) 158. 2017.
13Gaynor, JS, et al. “Veterinary applications of pulsed electromagnetic field therapy.” Research in Veterinary Science. Vol 119 1-8. 2018.
14Pinna, S, et al. “The effects of pulsed electromagnetic field in the treatment of osteoarthritis in dogs: clinical study.” Pakistan Veterinary Journal, Vol 33 (1): 96-100. 2012.
15Rawe, A, et al. “Control of postoperative pain with a wearable continuously operating pulsed radiofrequency energy device: a preliminary study.” Aesthetic Plastic Surgery, 36: 458-463. 2012.
16Al-Waili, NS et al. “Effects of hyperbaric oxygen on inflammatory response to wound and trauma: possible mechanism of action.” The Scientific World Journal 6, 435-441. 2006.
17Hochman, L, et al. “Veterinary hyperbaric oxygen therapy: a critical appraisal.” Plumbs therapeutic Brief. 2017.
18Braswell, C, et al. “Hyperbaric oxygen therapy.” Compendium: continuing education for Veterinarians. 2012.
19Rosenthal, R, et al. Hyperbaric oxygen reduces neuronal death and improves neurological outcome after canine cardiac arrest. Stroke, Vol 34 (5): 1311-1316. 2003.