Use of a colorimeter is a viable method to measure melanin and erythema content in the context of laser beam attenuation by use of a class IV laser in different tissues in dogs.

OBJECTIVE: Patient factors may alter laser photon attenuation, but these factors have not been adequately evaluated in live dogs. Our objective was to evaluate class IV laser beam attenuation (LBA) by canine tissues using a colorimeter to evaluate melanin and erythema indices. We hypothesized that greater melanin and erythema indices and unclipped hair would increase LBA, and these properties would vary among tissues. ANIMALS: 20 client-owned dogs. PROCEDURES: Between October 1 and December 1, 2017, colorimeter measurements and LBA in various tissues before and after clipping overlying hair were evaluated. Data were analyzed using generalized linear mixed models. Statistical significance was set at P < .05. RESULTS: LBA was greater in unclipped (98.6 ± 0.4%) than clipped hair (94.6 ± 0.4%). The least LBA occurred in the pinna (93%) while the greatest occurred in the caudal vertebra (100%) and caudal semitendinosis muscles (100%). Each mm of tissue thickness resulted in LBA of 11.6%. Each unit increase in melanin index resulted in a 3.3% increase in LBA. There was no association of LBA with erythema index. CLINICAL RELEVANCE: To our knowledge, this is the first study that evaluated LBA by different tissues in live dogs using a colorimeter to evaluate melanin and erythema indices. We recommend clipping hair prior to photobiomodulation to decrease laser beam attenuation and using increased laser doses in thicker tissues and dogs with high melanin content. The colorimeter may be helpful in customizing patient treatment dosimetry. Future studies are necessary to determine therapeutic laser doses for adequate photobiomodulation effects.

A Systematic Literature Review of Complementary and Alternative Veterinary Medicine: Laser Therapy.

Light therapy, or photobiomodulation, is a collective name for methods where tissue is irradiated with different types of light, with the aim of stimulating healing. Despite being frequently used, there is no consensus regarding the optimal treatment protocols for light therapy, nor its clinical efficacy. A systematic literature review was conducted, searching the relevant literature regarding light therapy in three databases, published between 1980-2020. The risk of bias in each article was evaluated. Forty-five articles met the inclusion criteria; 24 articles were regarding dogs, 1 was regarding cats, and the rest were regarding horses. The indications for treatment were musculoskeletal and neurologic conditions, skin disease and wounds, and pain. The literature review showed conflicting study results and unclear application for clinical use. This can be explained by the wide variety of treatment parameters used in the searched studies, such as wavelength, laser class, dose, and effect, as well as the frequency and duration of treatment. Although some beneficial effects were reported for light therapy, the studies also had limited scientific quality regarding these therapies, with a high or moderate risk of bias.

Thermographic Evaluation of the Duration of Skin Cooling After Cryotherapy in Dogs Following Tibial Plateau Leveling Osteotomy Surgery.

Objective: To evaluate the duration of cooling after cryotherapy on the skin over stifle joints in dogs after tibial plateau leveling osteotomy (TPLO) surgery using thermography. Materials and Methods: Seventeen client-owned dogs of various breeds were enrolled in the study. Dogs underwent TPLO surgeries, and on the next day, thermal imaging was performed on the operated stifle prior to cryotherapy for baseline. Orthogonal views were repeated at 30-min intervals until the skin over the stifle had thermally equilibrated. An ice pack was applied for 20 min on the medial and lateral aspects of the stifle. Each stifle was then re-imaged every 15 min for the first 60 min then every 30 min subsequently until the temperature was within 1°C of the pre-cryotherapy temperature. Results: Mean skin temperature of the medial view showed no significance difference compared to baseline value at 45 min after cryotherapy was discontinued and after 60 min for the lateral and cranial views. Mean skin temperature was overall higher in the medial view compared to the lateral and cranial during the rewarming period (except immediately after cold application). Mean skin temperatures of all views combined showed a significant decrease in temperature during cryotherapy application, with a slow increase until a plateau was reached after 45 min of rewarming. Conclusions and Clinical Relevance: Dogs undergoing TPLO for cranial cruciate ligament injury showed quicker rewarming period of superficial tissues compared to previous studies. Cryotherapy is a beneficial modality to reduce superficial tissue temperature in dogs undergoing TPLO, acknowledging that these dogs may require more frequent cryotherapy post-operatively due to more rapid rewarming time compared to dogs without surgery.

Platelet-rich plasma affects the proliferation of canine bone marrow-derived mesenchymal stromal cells in vitro.

BACKGROUND: Reported efficacy of platelet-rich plasma (PRP) in regenerative medicine is contradictory. We validated the effects of PRP on proliferation of canine bone marrow-derived multipotent mesenchymal stromal cells (K9BMMSCs) in vitro. PRP was extracted from blood of six dogs with osteoarthritis. K9BMMSCs were established from bone marrow and characterized for CD90 and CD19 expression by immunocytochemistry. Effects of PRP concentrations on viability of matching autologous K9BMMSCs were validated using MTS assay. RESULTS: Positive CD90 and negative CD19 expression confirmed MSC origin. PRP at 40% volume/volume concentration increased, while PRP at 80 and 100% v/v concentrations suppressed viability of tested K9BMMSCs. CONCLUSION: PRP concentration plays an important role in K9BMMSCs viability, which could affect tissue repairs in vivo.

Effect of Therapeutic Ultrasound on Calcaneal Tendon Heating and Extensibility in Dogs.

Objective: To (1) characterize the warming pattern of canine calcaneal tendons during and after four different therapeutic ultrasound (US) treatment protocols, and (2) to quantify changes in tarsal flexion immediately after therapeutic US treatment, and following return to baseline temperature. Design: A prospective, crossover, experimental study. Animals: Ten adult hound-type breed dogs. Procedure: Therapeutic ultrasound (3.3 MHz) was applied to one calcaneal tendon of anesthetized dogs using four different settings applied in random fashion (1.5 and 1.0 W/cm2 continuous, and 1.5 and 1.0 W/cm2 pulsed US) while the temperature of the tendon was recorded by a thermistor needle. The contralateral tendon was used to compare extensibility of the treated soft tissues by measuring changes in tarsal joint flexion before, immediately after, and 5-min after continuous US treatment at 1.5 W/cm2 for 10 min. Results: The greatest increase in tendon temperature occurred with continuous US at 1.5 W/cm2. Pulsed US resulted in minimal tendon heating. Most of the increase in tissue temperature occurred within the first 3 min of US application. Tarsal flexion increased significantly following US treatment; however, it returned to near baseline within 5 min after US was discontinued. Conclusion and Clinical Relevance: Continuous US of the calcaneal tendon at 1.5 W/cm2 resulted in the greatest increase in tissue temperature while maintaining a safe range of tissue temperature increase. Tendon heating and heat dissipation were slightly different from what has been reported for muscle. Our results suggest that 3.3 MHz US applied to tendon for >3 min may not provide additional tissue temperature increase. Therapeutic US resulted in increased tarsal flexion, however the change was only transitory. Therefore, stretching exercises should be performed during and immediately after US.

Variables Affecting Thigh Girth Measurement and Observer Reliability in Dogs.

Objective: The purpose of the study reported here was to describe variables affecting thigh girth measurements preoperatively and 2 weeks after surgical stabilization of the stifle and to examine inter- and intra-observer reliability. Animals: Ten hound-type dogs with experimental, unilateral, cranial cruciate ligament transection, and surgical stabilization. Procedures: Dogs were placed in lateral recumbency for measurements of thigh circumference after the stifle was placed in flexed (F), estimated standing (S), and extended (E) positions. Measurements were made at 50 and 70% of thigh length (TL), with hair unclipped and then clipped prior to surgery, before and 2 weeks after cruciate ligament transection and stifle stabilization, and with and without sedation. A spring tension measuring tape was used to determine thigh girth that allowed a consistent amount of end-tension to be applied to the tape. All measurements were made by two blinded individuals in triplicate, data were recorded for each set of measurements and the mean of the three measurements for each condition was used for analysis. Results: Thigh girth was significantly greater at the more proximal site of 50% TL (36.7 ± 2.6 cm) when compared to the 70% TL (31.7 ± 2.7 cm) (P = 0.001). Sedation did not significantly affect thigh girth at any stifle position at the 70% and 50% TL. Although there were no differences in thigh circumference between the flexion and standing positions at 50% TL (F 38.2 ± 2.8 cm, S 38.1 ± 2.9 cm) and 70% TL (F 33.6 ± 1.6 cm; S 33.6 ± 1.8 cm), full extension of the stifle resulted in significantly less thigh girth (50% TL 36.6 ± 2.6 cm, P = 0.006; 70% TL 31.7 ± 2.6 cm, P = 0.006). Significant decreases in thigh girth were seen after surgery in all limb positions at both measurement sites. The highest correlations between Observer 1 (OB1) and Observer 2 (OB2) with least differences in measurements were with the stifle in the extended position. Agreement between two observers using standard measuring technique was significant at both the 50% (OB1: 34.10 ± 2.93 cm, OB2: 34.08 ± 2.65 cm, P = 0.007, ICC = 0.984) and 70% (OB1: 29.89 ± 2.43 cm, OB2: 30.04 ± 2.30 cm, P = 0.004, ICC = 0.981) TL positions with the stifle placed in extended position. Conclusion and Clinical Importance: Thigh girth measurement may be useful as an outcome measure when appropriate measuring technique is used. It is recommended that thigh girth be obtained at a distance of 70% thigh length, with the leg in an extended position while in lateral recumbency, and the dog relaxed or under sedation. Further studies should be performed in a variety of clinical situations.

Evidence for canine rehabilitation and physical therapy.

This article reviews some important studies regarding canine physical rehabilitation. Bones, cartilage, muscles, ligaments, and tendons undergo atrophy if loading is decreased. Knowledge of the changes that occur with immobilization and the time course of events helps in the development of a rehabilitation program to improve tissue integrity. Outcome assessment instruments are clinically useful indicators of patient progress and the success of rehabilitation programs. A number of physical modalities are used in canine rehabilitation, although there are relatively few canine-specific studies. Rehabilitation has specific benefits in the treatment of various orthopedic and neurologic conditions.

Therapeutic laser in veterinary medicine.

Laser therapy is an increasingly studied modality that can be a valuable tool for veterinary practitioners. Mechanisms of action have been studied and identified for the reduction of pain and inflammation and healing of tissue. Understanding the basics of light penetration into tissue allows evaluation of the correct dosage to deliver for the appropriate condition, and for a particular patient based on physical properties. New applications are being studied for some of the most challenging health conditions and this field will continue to grow. Additional clinical studies are still needed and collaboration is encouraged for all practitioners using this technology.

Rehabilitation and physical therapy for selected orthopedic conditions in veterinary patients.

A specific diagnosis is needed to perform optimal rehabilitation of orthopedic problems. A well-planned rehabilitation program is important for orthopedic patients when surgical repairs are mechanically weak (eg, when repairing fractures in skeletally immature patients or when repairing tendons or ligaments). Joint immobilization is sometimes used to protect weak surgical repairs. The duration of immobilization should be minimized, particularly in situations with potential loss of joint motion. Evidence-based information regarding specific modalities and techniques for rehabilitation of injured dogs and cats is generally lacking. The choice of modalities and techniques must be based on common sense, knowledge of rehabilitation techniques, and clinical experience.

Use of an inverse dynamics method to describe the motion of the canine pelvic limb in three dimensions.

OBJECTIVE: To use an inverse dynamics method to describe the motion of the canine pelvic limb in 3 dimensions. ANIMALS: 6 healthy adult dogs. PROCEDURES: For each dog, 16 anatomic and tracking markers were used to define the center of rotation for the pelvic limb joints and a kinematic model was created to describe the motion of the pelvic limb. Kinetic, kinematic, and morphometric data were combined so that an inverse dynamics method could be used to define angular displacement, joint moment, and power of the hip, stifle, and tibiotarsal (hock) joints in the sagittal, frontal, and transverse planes. RESULTS: Movement and energy patterns were described for the hip, stifle, and hock joints in the sagittal, frontal, and transverse planes. CONCLUSIONS AND CLINICAL RELEVANCE: Knowledge of the 3-D movement of the pelvic limb can be used to better understand its motion, moment, and energy patterns in healthy dogs and provide a referent with which gaits of dogs with pelvic limb injuries before and after surgical repair or rehabilitation can be compared and characterized. This information can then be used to guide decisions regarding treatment options for dogs with pelvic limb injuries.

Use of an inverse dynamics method to compare the three-dimensional motion of the pelvic limb among clinically normal dogs and dogs with cranial cruciate ligament-deficient stifle joints following tibial plateau leveling osteotomy or lateral fabellar-tibial suture stabilization.

OBJECTIVE: To compare the 3-D motion of the pelvic limb among clinically normal dogs and dogs with cranial cruciate ligament (CCL)-deficient stifle joints following tibial plateau leveling osteotomy (TPLO) or lateral fabellar-tibial suture (LFS) stabilization by use of an inverse dynamics method. ANIMALS: 6 clinically normal dogs and 19 dogs with CCL-deficient stifle joints that had undergone TPLO (n = 13) or LFS (6) stabilization at a mean of 4 and 8 years, respectively, prior to evaluation. PROCEDURES: For all dogs, an inverse dynamics method was used to describe the motion of the pelvic limbs in the sagittal, frontal, and transverse planes. Motion and energy patterns for the hip, stifle, and tibiotarsal (hock) joints in all 3 planes were compared among the 3 groups. RESULTS: Compared with corresponding variables for clinically normal dogs, the hip joint was more extended at the beginning of the stance phase in the sagittal plane for dogs that had a TPLO performed and the maximum power across the stifle joint in the frontal plane was greater for dogs that had an LFS procedure performed. Otherwise, variables in all planes were similar among the 3 groups. CONCLUSIONS AND CLINICAL RELEVANCE: Gait characteristics of the pelvic limb did not differ between dogs that underwent TPLO and dogs that underwent an LFS procedure for CCL repair and were similar to those of clinically normal dogs. Both TPLO and LFS successfully provided long-term stabilization of CCL-deficient stifle joints of dogs with minimal alterations in gait.

Effects of partial immersion in water on vertical ground reaction forces and weight distribution in dogs.

OBJECTIVE: To assess the impact of partial immersion in water on vertical ground reaction force (vGRF) and vGRF distribution in dogs. ANIMALS: 10 healthy adult dogs. PROCEDURES: Weight placed on each limb of each dog was measured 3 times (1 scale/limb). Dogs were then immersed in water to the level of the tarsal, stifle, and hip joints, and vGRFs were measured. Coefficients of variation for triplicate measurements were calculated. Mixed-effects ANOVAs were used to compare the vGRF for thoracic versus pelvic limbs and the vGRF at various immersion levels as well as the vGRF distributions among limbs at various immersion levels. RESULTS: Mean±SD vGRF before immersion was 249±34 N. It was significantly decreased by 9% after immersion to the tarsal joints (227±32 N), by 15% after immersion to the stifle joints (212±21 N), and by 62% after immersion to the hip joints (96±20 N). The vGRFs were significantly higher for the thoracic limbs than for the pelvic limbs before immersion and at all immersion levels. Dogs placed 64% of their weight on the thoracic limbs before immersion. That ratio did not differ significantly after immersion to the tarsus (64%) or stifle (63%) joints, but was significantly larger after immersion to the hip joints (71%). CONCLUSIONS AND CLINICAL RELEVANCE: vGRF decreased as the depth of immersion increased. The thoracic limb-to-pelvic limb vGRF ratio was unchanged in dogs after immersion to the tarsal or stifle joints, but it increased after immersion to the hip joints.

Bone and lean tissue changes following cranial cruciate ligament transection and stifle stabilization.

Following cranial cruciate ligament transection and extracapsular stabilization, dual-energy X-ray absorptiometry was used to analyze bone mineral content and lean tissue mass in the surgical and nonsurgical legs (n=14) at 0, 2, 4, and 8 weeks, and to evaluate bone mineral content and bone mineral density (BMD) of the proximal, mid-, and distal tibia of both the surgical and nonsurgical legs (n=15) at 0, 5, and 10 weeks. There was significant loss of bone mineral content and lean tissue in the surgical leg compared to the nonsurgical leg. Significant loss in bone mineral content and BMD was detected in the tibia of the surgical leg and was most pronounced in the metaphyseal region.

Biomechanics of rehabilitation.

The biomechanics of motion and rehabilitation are complex, with many tissue types and structures involved. In addition, consideration must be given to the stage of tissue healing with some injuries, such as fractures.A more thorough knowledge of some of the infrequently discussed biomechanical aspects of musculoskeletal tissues and motion during rehabilitation, combined with known features of tissue recovery, should enhance the development of rehabilitation programs for patients.

Introduction to veterinary physical rehabilitation.

Physical therapy is a profession with an established scientific basis in human beings and companion animals. It has a large number of clinical applications in the restoration, maintenance, and promotion of optimal physical function. In providing physical therapy, the goal is to restore, maintain, and promote optimal function, optimal fitness, wellness, and quality of life as they relate to movement disorders and health. A major emphasis is to prevent or minimize the onset, clinical signs, and progression of impairments, functional limitations, and disabilities that may result from diseases, disorders, conditions, and injuries.

Rehabilitation for the orthopedic patient.

An understanding of orthopedic conditions and their medical and surgical treatment is important to help the therapist develop a treatment plan that will help the patient return to function quickly with minimal complications. The therapist must constantly assess the patient for improvement or complications and adjust the therapy plan accordingly. Knowledge of the stages of tissue healing and of the strength of tissues is critical to avoid placing too much stress on the surgical site, yet some challenge to tissues must be provided to optimize the return to function.

Emerging modalities in veterinary rehabilitation.

Many new modalities have been introduced in human and veterinary physical rehabilitation. In many instances, there is sound theory of how they may impact the physiology of various cells, tissues, or organs. This article reviews some of the modalities that have been introduced recently in human and veterinary rehabilitation. Topics include low-level laser, phototherapy, and extracorporeal shock wave treatment.

Assistive devices, orthotics, and prosthetics.

Deciding on which supportive device, orthotic, or prosthetic is best suited for a given patient is a complex process involving many different factors. The ability to manage biomechanical abnormalities successfully may be enhanced by an understanding of the properties of the various materials that comprise these devices, their effect on functional performance, and other associated patient factors. Veterinary health care providers are faced with the challenge of effectively addressing the physiologic and fiscal needs of the patient in a rapidly changing patient care environment.

Comparison of perioperative analgesic protocols for dogs undergoing tibial plateau leveling osteotomy.

OBJECTIVE: To compare effects of 3 commonly used perioperative analgesic protocols (epidural injection, intra-articular injection, and intravenous [IV] injection) for management of postoperative pain in dogs after tibial plateau leveling osteotomy (TPLO). STUDY DESIGN: Prospective, randomized clinical trial. ANIMALS: Fifty-six healthy dogs with naturally occurring cranial cruciate ligament rupture. METHODS: Dogs were premedicated with IV hydromorphone and acepromazine and were randomly assigned to receive either E (preoperative epidural injection with morphine and bupivacaine), IA (pre- and postoperative intra-articular injections of bupivacaine), or C (neither epidural morphine and bupivacaine, nor intra-articular bupivacaine). All dogs were administered hydromorphone (0.05 mg/kg IV) at extubation and as needed to maintain comfort postoperatively. Patients were observed and monitored continuously for 24 hours and discomfort was assessed using visual analog pain scores (VASs), multifactorial pain scores (MPSs), and response to a pressure nociceptive threshold (PNT) measuring device. Time to 1st dose and the total doses of hydromorphone required to achieve adequate comfort for each dog were recorded. RESULTS: No differences in measured indices of postoperative pain were observed between dogs of each treatment group; VAS (P=.190), MPS (P=.371), and PNT (P=.160). Time to 1st analgesic intervention was longer for Group E compared with Group C (P=.005) and longer for Group IA compared with Group C (P=.032). Although time to 1st intervention between Groups E and IA were longer for Group E, differences were not significant. To provide an adequate level of comfort, more analgesic interventions were administered to dogs in Group C compared with dogs in group E (P=.015). On average, more hydromorphone was administered to Group C compared with Group IA (P=.072) and to Group IA compared with Group E (P=.168), but statistical significance was not reached for these data. CONCLUSIONS: In this study population, significant differences were seen in time to 1st hydromorphone dose between Groups E and IA compared with Group C. As well, more supplemental analgesia was administered to Group C compared with Group E to maintain the same level of postoperative comfort. Although differences between Groups E and IA tended to favor the epidural group, differences were minimal and not statistically significant. CLINICAL RELEVANCE: Our results suggest that regardless of analgesic protocol, measured indices of pain in dogs after TPLO can be minimized if dogs are continuously observed and appropriately supplemented with parenteral opioids. However, the frequency of postoperative opioid dosing can be minimized and may be a factor when contemplating supplementary use of epidural or intra-articular injections as part of a balanced analgesic approach.