Influence of leash side and handlers on pressure mat analysis of gait characteristics in small-breed dogs

Effect of Transcutaneous Electrical Nerve Stimulation on Gait Parameters in Dogs with Osteoarthritis

Osteoarthritis is a common degenerative disease in dogs, often manifested as pain, joint swelling, and lameness. Despite the lack of scientific evidence for its treatment efficacy, transcutaneous electrical nerve stimulation (TENS) is used in dogs as a pain-relieving treatment. This randomised single-blinded cross-over study investigated the effect of TENS on gait parameters in fifteen dogs with osteoarthritis. Stance time, swing time, stride time, stride length, peak vertical force (%BW), vertical impulse (%BW*sec), and symmetry indices were obtained using a pressure-sensitive mat. TENS treatment of 80 Hz and 100 µs with an individually selected amplitude was conducted for 45 min once daily for a treatment period of seven or ten days. No significant differences were seen between TENS and placebo for any of the gait parameters. Hence, in this study, TENS did not affect gait parameters, compared to placebo. Further studies are needed to confirm the observations.

The Effect of Therapeutic Exercise on Body Weight Distribution, Balance, and Stifle Function in Dogs following Stifle Injury

Stifle injury is common in the companion dog population, affecting weight bearing, neuromuscular control, and balance. Therapeutic exercises after stifle injury seem to be effective, but high-quality research evaluating the effects is lacking. This randomized controlled trial evaluated the effects of a 12-week progressive therapeutic home exercise protocol on three-legged standing, targeting balance and postural- and neuromuscular control and disability in dogs with stifle injury. Thirty-three dogs with stifle injury were randomly allocated to intervention (n = 18) and control groups (n = 15), both receiving a standard rehabilitation protocol. Additionally, the intervention group received a progressive therapeutic exercise protocol. The outcome measures were static body weight distribution between hindlimbs, balance control, the canine brief pain inventory, and the Finnish canine stifle index. Both groups improved after the intervention period, but the group using the progressive therapeutic exercise protocol improved to a greater extent regarding static body weight distribution between the hindlimbs (I: median = 2.5%, IQR = 1.0-4.5; C: median = 5.5%, IQR = 3.0-8.8), pain-related functional disability (I: median = 0.0, IQR = 0.0-0.2; C: median = 0.9, IQR = 0.1-1.8), and stifle function (I: median = 25.0, IQR = 9.4-40.6; C: median = 75.0, IQR = 31.3-87.5), with intermediate to strong effects. These clinically relevant results indicate that this home exercise program can improve hindlimb function and restore neuromuscular control.

An update on mobility assessment of dogs with musculoskeletal disease

Mobility impairments associated with musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, affect approximately 200,000 dogs annually and pose a notable challenge to canine health and welfare. Osteoarthritis causes the remodelling of synovial joints, alongside inflammation and impaired mechanical function which can be extremely debilitating. Secondary osteoarthritis commonly affects dogs and can be exacerbated by previous joint abnormalities, such as patellar luxation or cranial cruciate ligament rupture. Although musculoskeletal diseases can affect dogs of any age, the early subtle signs of gait abnormalities are perhaps missed by owners, thus, dogs may be in the latter stages of osteoarthritis progression when they are presented to veterinarians. Dogs showing subtle signs of gait abnormalities must be presented to veterinary practices for acute diagnosis to prevent long-term deterioration. Musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, are commonly diagnosed via visible radiographic changes. However, veterinarians can use a combination of subjective and objective clinical scoring systems, such as clinical metrology instruments and gait assessment in conjunction with radiography to aid their diagnosis and longitudinal monitoring of musculoskeletal diseases. These scoring systems may be more sensitive to earlier signs of mobility impairments in dogs, ultimately, promoting increased canine health and welfare by enabling pain reduction, improvement of muscle strength and preservation of joint function. Current canine mobility scoring systems available to veterinarians will be discussed in turn throughout this review for implementation into clinical practice.

Breed-typical front limb angular deformity is associated with clinical findings in three chondrodysplastic dog breeds

Angular front limb deformity (ALD) refers to an excessively curved limb conformation, which is seen in some chondrodysplastic dog breeds. Common characteristics of ALD include carpal valgus (VALG), front limb rotation (ROT), elbow incongruity, and lateral radial head subluxation. These may cause lameness and discomfort in affected dogs. The clinical impact and breed-specific characteristics of front limb conformation in chondrodysplastic breeds are unknown. This prospective and cross-sectional study aimed to investigate differences in front limb conformation between three chondrodysplastic breeds. We further evaluate whether front limb conformation is associated with clinical findings and limb function. We propose novel methods to classify findings in the interosseous space and to quantify lateral radial head subluxation. Data from a total of 224 front limbs from 112 dogs of three chondrodysplastic dog breeds (30 Standard Dachshunds, 29 Skye terriers, and 53 Glen of Imaal terriers) were included in the study. Front limb VALG and ROT were measured with a goniometer. From the radiographs, the elbow joint was graded for incongruity (INC), and the humeroradial angle (HRA) was measured to assess lateral radial subluxation. The association of front limb conformation with clinical signs and limb function was investigated using orthopedic examination, goniometric and kinetic measurements, and radiography. The breeds differed significantly in their front limb conformation. The Dachshund had the least ROT and the least radial head subluxation. The Skye terrier had the most VALG, the most radial head subluxation, and the largest prevalence of moderate and severe INC. The Glen of Imaal terrier had the most ROT. In addition, INC, ROT, VALG, and HRA were found to be independent of each other and were associated with several measurable clinical abnormalities and limb function such as pain, lameness, limited range of motion, and elbow joint osteoarthritis. This implies that VALG, ROT, and HRA could be used in addition to INC grading when choosing musculoskeletal characteristics of dogs suitable for breeding.

Objective Gait Analysis: Review and Clinical Applications

Objective kinetic and kinematic data can be used as an objective measure of treatment intervention over time but can also be used to evaluate progress of clinical patients. Force plate and pressure sensitive walkway systems both offer the clinician the ability to obtain useful kinetic data, whereas additional equipment is required to obtain kinematic data. Which system is preferred depends on what specific data the researcher or clinician hopes to acquire; both are accurate and consistent, and each offers pros and cons compared with the other that must be considered.

Static Body Weight Distribution and Girth Measurements Over Time in Dogs After Acute Thoracolumbar Intervertebral Disc Extrusion

Dogs with thoracolumbar intervertebral disc extrusion (TL-IVDE) can exhibit variable neurologic deficits after decompressive surgery. The objectives of this study were to quantify changes in static weight distribution (SWD) and limb and body circumference over time in dogs recovering from surgery for TL-IVDE. Dogs with acute TL-IVDE were prospectively evaluated at baseline (48–72 h post-operatively), 2, 4, 8, and 12 weeks post-operatively. Commercially-available digital scales were used to measure weight distributed to the pelvic limbs (PL%) and asymmetry between left and right pelvic limbs (LRA), each expressed as a percentage of total body weight. Trunk and thigh circumference measurements were performed using a spring-loaded tape measurement device. Measurements were performed in triplicate, compared to neurologically normal small breed control dogs and analyzed for changes over time. P <0.05 was significant. Twenty-one dogs were enrolled; 18 regained ambulation and 3 did not by study completion. PL% increased from 27.6% at baseline to 30.7% at 12 weeks but remained lower than in control dogs (37%) at all time points (p < 0.0001), even excluding dogs still non-ambulatory at 12 weeks (p < 0.025). LRA was similar to the control dogs, and did not have an association with surgical side. Caudal trunk girth decreased over time to 95% of baseline (p = 0.0002), but this was no longer significant after accounting for reductions in body weight (p = 0.30). Forward shifting of body weight persisted in dogs with TL-IVDE 12 weeks after surgery even among ambulatory dogs. SWD and circumference measurements could provide additional objective measures to monitor recovery.

Four-limb wireless IMU sensor system for automatic gait detection in canines

This study aims to develop a 4-limb canine gait analysis system using wireless inertial measurement units (IMUs). 3D printed sensor holders were designed to ensure quick and consistent sensor mounting. Signal analysis algorithms were developed to automatically determine the timing of swing start and end in a stride. To evaluate the accuracy of the new system, a synchronized study was conducted in which stride parameters in four dogs were measured simultaneously using the 4-limb IMU system and a pressure-sensor based walkway gait system. The results showed that stride parameters measured in both systems were highly correlated. Bland-Altman analyses revealed a nominal mean measurement bias between the two systems in both forelimbs and hindlimbs. Overall, the disagreement between the two systems was less than 10% of the mean value in over 92% of the data points acquired from forelimbs. The same performance was observed in hindlimbs except for one parameter due to small mean values. We demonstrated that this 4-limb system could successfully visualize the overall gait types and identify rapid gait changes in dogs. This method provides an effective, low-cost tool for gait studies in veterinary applications or in translational studies using dog models of neuromuscular diseases.

Best practices for measuring and reporting ground reaction forces in dogs

Kinetic gait analysis and ground reaction forces (GRFs) have been used in hundreds of scientific manuscripts. Specific methodology, interpretation of results, and translation to clinical veterinary medicine have been inconsistent. This impedes the advance of veterinary medicine and poses a risk to patients. The objective of this report was to address methodological variations and share our consensus on a recommended approach with viable alternatives to data collection methods, analysis, reporting, and interpretation for GRFs in the dog. Investigators with experience performing kinetic gait analysis reviewed the literature and discussed the topics that most influenced GRF data collection, reporting, and interpretation. Methodological variations were reported and a consensus from the group was devised. There are several reasonable alternatives to collect, report, and interpret GRFs in dogs appropriately. Attention to detail is required in several areas to collect and report them. This review and consensus report should assist future investigations and interpretations of studies, optimize comparison between publications, minimize use of animals, and limit the investment in cost and time.

Reliability of range-of-motion measurements of healthy dogs examined while walking on a treadmill

OBJECTIVE

To determine the reliability of range-of-motion (ROM) measurements and describe physiologic differences in ROM or habituation effects during gait analysis of healthy dogs walking on a treadmill.

ANIMALS

11 orthopedically normal dogs.

PROCEDURES

ROM of appendicular joints was determined for each dog while walking on a treadmill on 3 consecutive examination days and once again 6 weeks later. Significant differences in ROM between examination days were determined and quantified. As a measure of reproducibility, the coefficient of variation for repeated measurements was calculated, as were the minimum differences necessary to distinguish between physiologic variation and true change in ROM.

RESULTS

Mean ROM of the shoulder, elbow, and carpal joints varied among examination days between 29.9° and 33.1°, 49.4° and 52.8°, and 7.7° and 88.1°, respectively. Mean associated minimum differences were 12.0°, 14.1°, and 35.6°. Mean ROM of the hip, knee, and tarsal joints varied between 32.9° and 35.8°, 33.7° and 36.8°, and 31.7° and 33.5°, respectively. Mean associated minimum differences were 16.2°, 14.0°, and 9.2°. Only ROM of the elbow joint was reproducible to a small degree. Few systematic effects were detected.

CONCLUSIONS AND CLINICAL RELEVANCE

Measurement of ROM in healthy dogs walking on a treadmill was shown to be diagnostically unreliable owing to high variation among examination days. However, random physiologic fluctuations could be distinguished from systematic effects, demonstrating the importance of reliably applicable threshold values for follow-up treadmill examinations. The applicability of the minimum differences determined here to orthopedically diseased dogs remains to be determined.

Thermal Imaging Following Exercise in Working Dogs

Disaster search dogs traverse diverse and unstable surfaces found in collapsed buildings. It is unknown if the physical conditioning on a treadmill involves the same muscle groups that are involved in rubble search. This 14-week prospective cohort study was conducted to investigate changes within the thermal gradients of specific dog muscles following treadmill compared to rubble search. Nine dogs, ranging in age from 6 months to 4 years, were randomly assigned to one of two groups. Each week the two groups would participate in either 20 min of treadmill or rubble searches. Prior to exercise, the dogs were weighed and then kenneled in a temperature-controlled study room for 20 min at 21°C. Pre-exercise thermal images were then captured of the standing dog from the dorsal, left and right lateral, and caudal perspectives, and of the sitting dog from the rostral perspective. Following a 10-min warm-up period of stretches, dogs proceeded to either treadmill or search. Upon completion, dogs were kenneled in the study room for 20 min prior to post-exercise thermal images. Images were sectioned into 22 muscle regions, the pre-exercise images were subtracted from the post-exercise images to determine the temperature difference (ΔT) for that dog, on that day, for that activity. Thermography measures radiant energy, temperature, and converts this information into an image. This study looked at ΔT within a region pre and post-exercise. The study failed to find a statistically significant difference in the ΔT within each muscle group between treadmill and search activities. There was a decrease in ΔT within all muscle regions over the of the study except for the right cranial shoulder, right caudal shoulder, and right hamstring for the treadmill activity only. The decrease was significant in the pelvis, left longissimus, right cranial shoulder for the search activity, left oblique, left caudal shoulder, and left quadricep muscular regions. These findings suggest that ΔT in muscle groups are similar between treadmill exercise and rubble search. Regardless of the exercise type, 14 weeks of structured Search and Rescue training and treadmill exercise resulted in less ΔT associated with a structured weekly exercise.

Dog Pulling on the Leash: Effects of Restraint by a Neck Collar vs. a Chest Harness

Leash pulling is a concern for dog owners and can be detrimental to the health and welfare of dogs. Neck-collars and back-connection harnesses are popular restraint types. Harnesses have been proposed as a better and more considerate option for canine health and welfare. Anecdotally, dogs pull more when wearing a back-connection harness; however, there is no scientific evidence for this perception. This study aimed to investigate how strongly dogs pull on the lead to achieve a food treat or toy under restraint by a neck-collar versus a back-connection harness. A within-subject counterbalanced design was used for the study, involving 52 shelter dogs. A customised canine leash tension metre was connected to the collar or harness to record the pulling of the dogs, including measuring the maximal and mean leash tension, and the time spent pulling. In addition, dog behaviours were recorded using two cameras from two separate directions. The maximal and mean leash tension and the pulling time were greater under restraint by harness when attracting dogs with food treats. No significant difference between harness and collar was found in potential stress-related behaviours (e.g. tail and ear positions, lip-licking, and panting). However, dogs looked at the experimenter more often when restrained by harness than collar in the food treat attraction test. No significant difference was detected between harness and collar with respect to leash tension and stress-related behaviours in the toy attraction test. These findings suggest that dogs tend to pull stronger and more steadily when wearing a back-connection harness compared to a neck collar to reach the food treat but not the toy.

Kinetic gait analysis in healthy dogs and dogs with osteoarthritis: An evaluation of precision and overlap performance of a pressure-sensitive walkway and the use of symmetry indices

In veterinary practice, a thorough gait examination is essential in the clinical workup of any orthopedic patient, including the large population of dogs with chronic pain as a result of osteoarthritis. The traditional visual gait examination is, however, a subjective discipline, and systems for kinetic gait analysis may potentially offer an objective alternative for gait assessment by the measurement of ground reaction forces. In order to avoid unnecessary testing of patients, a thorough, stepwise evaluation of the diagnostic performance of each system is recommended before clinical use for diagnostic purposes. The aim of the study was to evaluate the Tekscan pressure-sensitive walkway system by assessing precision (agreement between repetitive measurements in individual dogs) and overlap performance (the ability to distinguish dogs with lameness due to osteoarthritis from clinically healthy dogs). Direction of travel over the walkway was investigated as a possible bias. Symmetry indices are commonly used to assess lameness by comparing ground reaction forces across different combinations of limbs in each dog. However, SIs can be calculated in several different ways and specific recommendations for optimal use of individual indices are currently lacking. Therefore the present study also compared indices in order to recommend a specific index preferable for future studies of canine osteoarthritis. Forty-one clinically healthy dogs and 21 dogs with osteoarthritis were included in the study. High precision was demonstrated. The direction of travel over the walkway was excluded as a possible bias. A significant overlap was observed when comparing ground reaction forces measured in dogs with osteoarthritis compared to clinically healthy dogs. In some affected dogs, symmetry indices comparing contralateral limbs differed from clinically healthy dogs, but in general, the overlap performance was insufficient and, consequently, general use of this method for diagnostic purposes in dogs with osteoarthritis cannot be recommended.

Reliability of kinetic measurements of healthy dogs examined while walking on a treadmill

OBJECTIVE

To investigate whether an actual improvement in gait could be differentiated from physiologic differences or habituation effects during gait analysis of dogs.

ANIMALS

11 healthy dogs.

PROCEDURES

On 4 examination days, kinetic parameters were measured while dogs were walking on a treadmill. Differences in mean parameter values and habituation effects (ie, effect sizes) were quantified and compared among examination days. Coefficients of variation for repeated measurements were calculated to determine measurement reproducibility, and minimum differences were calculated to distinguish between physiologic fluctuation and an actual change in gait pattern.

RESULTS

Among the 4 examination days, mean absolute differences in peak vertical force and vertical impulse (VI) varied from 1.5% to 5.3% of body weight (BW) and 0.9% to 1.8% of BW·s, respectively. Mean absolute differences in the percentage of stance-phase duration (%SPD) and relative stride length (RSL) varied from 0.9% to 3.2% and 1.7% to 3.0%, respectively. Reproducibility of parameter measurements was good. Values for %SPD had the lowest amount of dispersion and largest effect size, suggesting a habituation effect for this parameter. Calculated minimum differences among the days for peak vertical force, VI, %SPD, and RSL did not exceed 9.9% of BW, 3.3% of BW·s, 5.8 percentage points, and 5.2 percentage points, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

The %SPD of healthy dogs walking on a treadmill was the most sensitive and diagnostically reliable of the measured kinetic parameters, in contrast to VI and RSL. Findings suggested that actual changes can be distinguished from random physiologic fluctuations during gait analysis of dogs.

A pilot study of 4CYTE™ Epiitalis® Forte, a novel nutraceutical, in the management of naturally occurring osteoarthritis in dogs

The primary goal of this pilot study was to assess, the efficacy of a new nutraceutical, 4CYTE™ Epiitalis® Forte, containing, as a standalone, a proprietary plant oil extract, Epiitalis, in dogs presenting with signs of osteoarthritis (OA). Fifty dogs aged 9.2 (±3.2) years with signs of naturally occurring OA were included in this report. They were free of other comorbidities and were not on any medications except for those utilised for managing their OA. In these dogs, the current treatments were continued to avoid any sudden changes in their disease management. The effects of the 4CYTE Epiitalis Forte were assessed both at the beginning and at the end of a 1 month-long treatment period. The evaluation consisted of an objective lameness assessment (TPI%[total pressure index]) using a gait analysis (GAITRite® Portable Walkway System) and a subjective quality-of-life questionnaire, the Helsinki Chronic Pain Index (HCPI). Additional exploratory objective measurements included the Symmetry Index (SI) and the fore/hind limb ratio (T/P TPI%). Of dogs, 74% (34/46) registered a numerical improvement in TPI% in their worse limb. In addition, of the 93.5% of the dogs that demonstrated improvement in their HCPI scores by at least 5% on the quality-of-life questionnaire, 79% demonstrated improvements in gait based on TPI%. Finally, there were improvements measured in both exploratory objective endpoints SI and T/P TPI%. These encouraging results will be used to develop a protocol for a follow-up placebo-controlled randomised study to confirm the efficacy of this new nutraceutical for dogs suffering from OA.

Transference of reference intervals for variables of instrumented gait analysis in walking dogs

OBJECTIVE

To use the small data approach of the Clinical and Laboratory Standards Institute (CLSI) to evaluate the transferability of reference intervals (RIs) for kinetic variables obtained with instrumented gait analysis (IGA) in dogs from an RI-originator laboratory to another laboratory that used the same data acquisition and analytic techniques for IGA in walking dogs.

ANIMALS

27 adult client-owned dogs without evidence of lameness.

PROCEDURES

Dogs were individually walked at their preferred velocity on a pressure-sensing walkway for IGA at the Colorado State University Animal Gait Laboratory (CSU-AGL), and 6 valid trials were analyzed for each dog. The small data approach of the CLSI was then used to evaluate transferability of RIs previously established at the Purdue University Animal Gait Laboratory (PU-AGL). A linear model was used to establish weight-dependent RIs for peak vertical force (PVF).

RESULTS

Results indicated that RIs of dynamic weight distribution (DWD), DWD symmetry index, DWD coefficient of variation, PVF symmetry index, and PVF coefficient of variation were transferable from PU-AGL to CSU-AGL, whereas the weight-dependent RIs for PVF were not. Regression slopes for PVF versus body weight were greater for all limbs in dogs tested at the CSU-AGL, compared with historic results for dogs tested at the PU-AGL.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of the small data approach method of the CLSI to validate transference of RIs for IGA kinetic variables in walking dogs was simple and efficient to perform and may help facilitate clinical and research collaborations on gait analysis.

Temporo-spatial and kinetic gait parameters in English setter dogs

Walking analysis systems have begun to be used in veterinary medicine in recent years. The pressure-sensitive walkway is one of the systems through which we can obtain temporo-spatial and kinetic variables of walking. Therefore, the aim of this study was to investigate the walking characteristics of English Setter dogs using a pressure-sensitive system. Twenty-five English Setter dogs were included in the study. Temporo-spatial and kinetic gait parameters were obtained with the pressure-sensitive walkway system. Centre of pressure values were taken separately for the forelimbs and hindlimbs and were statistically analysed. The force values in the forelimb were found to be greater than in the hindlimb during walking. According to the results of dynamic pedobarographic evaluation, the highest-pressure values were found at the 2nd and 3rd digital pads for the forelimbs and on the 3rd and 4th digital pads for the hindlimbs. During the stance, 64.58% of the weight was found to be on the forelimbs. No difference was found between the forelimbs and the hindlimbs in centre of pressure analysis. As conclusion, the gait data obtained from the English Setter dogs can be used in future research to identify animals that may have neurological or orthopaedic problems.

Gait analysis in French bulldogs with and without vertebral kyphosis

The study objective was to compare temporal-spatial and kinetic gait variables in neurologically normal French bulldogs with and without vertebral kyphosis. French bulldogs presented to a dedicated brachycephalic clinic were prospectively enrolled. All dogs underwent general physical, orthopaedic, and neurological examination prior to study inclusion. The presence of vertebral kyphosis was evaluated by computed tomography and kyphosis was defined as a Cobb angle exceeding 10°. Gait variables were collected using a pressure-sensitive GAITRite walkway with GAITFour software and included measurement of total pressure index (TPI) defined as the sum of peak pressure values recorded from each activated sensor by a paw during mat contact. Fifteen French bulldogs with (n=8) and without kyphosis (n=7) were included. Cobb angle in kyphotic dogs ranged from 14.9° to 39.5°. Univariate analyses were initially performed to examine the association between kyphosis and 16 gait variables. When those variables found to be associated (P<0.2) were taken forward into multivariate generalised linear mixed models (accounting for dog, velocity and side), kyphosis had a significant effect upon TPI of the forelimbs and TPI symmetry ratio (P<0.05); however, the size of these effects was small. Although vertebral kyphosis is rarely associated with neurological deficits, it was associated with subtle alterations in kinetic gait variables (TPI forelimbs and TPI symmetry ratio). Further studies are needed to evaluate the clinical importance of altered gait variables in French bulldogs with kyphosis.

Pressure Mat Analysis of Walk and Trot Gait Characteristics in 66 Normal Small, Medium, Large, and Giant Breed Dogs

Objectives: To document temporospatial variables and gait symmetry measured by the GAITRite® system for normal, healthy dogs at the walk and trot with the leash side recorded.

Study Design: Observational, prospective, cohort study.

Sample Population: 66 healthy dogs of various common breeds with no evidence of lameness that were small (< 10 kg), medium (10- < 25 kg), large (25- < 40 kg), or giant (≥40 kg).

Methods: Dogs walked and trotted at their preferred velocity on a pressure sensing walkway system. Video observation confirmed inclusion criteria were met for three valid trials at each gait for each dog. Coefficients of variance were used to summarize the data for analysis. Fore and hindlimb ratios were compared. Gait symmetry was assessed with the leash on the left and right side.

Results: Coefficients of variation for gait parameters ranged from 20 to 28% for all except velocity and hind reach. There was no statistically significant difference in differences in fore and hindlimb ratios for stance %, GLS, TPI, or step:stride ratio, across weight categories or between walk and trot. Less than 8% of normal dogs had a GLS score < 90 (indicating lameness). Leash side did influence gait symmetry, since GLS, TPI, and step:stride all had statistically significant differences in means between leash side, irrelevant of the weight category or gait.

Conclusions and Clinical Relevance: This system allowed simple, reliable gait assessment and values reported may be considered normal reference ranges for temporospatial variables collected with this system within the weight ranges and gaits reported. Controlling leash side and patient size is recommended for therapeutic intervention studies.

Evaluation of the Effect of a Single Intra-articular Injection of Allogeneic Neonatal Mesenchymal Stromal Cells Compared to Oral Non-Steroidal Anti-inflammatory Treatment on the Postoperative Musculoskeletal Status and Gait of Dogs over a 6-Month Period after Tibial Plateau Leveling Osteotomy: A Pilot Study

OBJECTIVE

Compare the clinical and pressure walkway gait evolution of dogs after a tibial plateau leveling osteotomy (TPLO) for a cranial cruciate ligament rupture (CrCLR) and treatment with either a 1-month course of non-steroidal anti-inflammatory drugs (NSAIDs) or a single postoperative intra-articular (IA) injection of allogeneic neonatal mesenchymal stromal cells (MSCs).

STUDY DESIGN

Prospective, double-blinded, randomized, controlled, monocentric clinical study.

ANIMALS

Sixteen client-owned dogs.

MATERIALS AND METHODS

Dogs with unilateral CrCLR confirmed by arthroscopy were included. Allogeneic neonatal canine MSCs were obtained from fetal adnexa retrieved after C-section performed on healthy pregnant bitches. The dogs were randomly allocated to either the "MSCs group," receiving an IA injection of MSCs after TPLO, followed by placebo for 1 month, or the "NSAIDs group," receiving IA equivalent volume of MSCs vehicle after TPLO, followed by oral NSAID for 1 month. One of the three blinded evaluators assessed the dogs in each group before and after surgery (1, 3, and 6 months). Clinical score and gait and bone healing process were assessed. The data were statistically compared between the two groups for pre- and postoperative evaluations.

RESULTS

Fourteen dogs (nine in the MSCs group, five in the NSAIDs group) completed the present study. No significant difference was observed between the groups preoperatively. No local or systemic adverse effect was observed after MSCs injection at any time point considered. At 1 month after surgery, bone healing scores were significantly higher in the MSCs group. At 1, 3, and 6 months after surgery, no significant difference was observed between the two groups for clinical scores and gait evaluation.

CONCLUSION

A single IA injection of allogeneic neonatal MSCs could be a safe and valuable postoperative alternative to NSAIDs for dogs requiring TPLO surgery, particularly for dogs intolerant to this class of drugs.