A missed opportunity: A scoping review of the effect of sex and age on osteoarthritis using large animal models

OBJECTIVE

The objective was to critically analyze the published literature accounting for sex differences and skeletal age (open vs. closed physis) in preclinical animal models of OA, including the disaggregation of data by sex and skeletal maturity when data is generated from combined sex and/or multi-aged cohorts without proper confounding.

METHOD

A scoping literature review of PubMed, Web of Science, EMBASE, and SCOPUS was performed for studies evaluating the effect of sex and age in experimental studies and clinical trials utilizing preclinical large animal models of OA.

RESULTS

A total of 9727 papers were identified in large animal (dog, pig, sheep, goat, horse) models for preclinical OA research, of which 238 ex vivo and/or in vivo studies disclosed model type, animal species, sex, and skeletal age sufficient to analyze their effect on outcomes. Dogs, followed by pigs, sheep, and horses, were the most commonly used models. A paucity of preclinical studies evaluated the effect of sex and age in large animal models of naturally occurring or experimentally induced OA: 26 total studies reported some kind of analysis of the effects of sex or age, with 4 studies discussing the effects of sex only, 11 studies discussing the effects of age only, and 11 studies analyzing both the effects of age and sex.

CONCLUSION

Fundamental to translational research, OARSI is uniquely positioned to develop recommendations for conducting preclinical studies using large animal models of OA that consider biological mechanisms linked to sex chromosomes, skeletal age, castration, and gonadal hormones affecting OA pathophysiology and treatment response.

Pulsed shortwave electromagnetic field therapy increases quality of life in canines with symptoms of osteoarthritics

BACKGROUND

Joint stiffness, lameness and reduced activity levels are common inflammatory responses observed in canines and have significant impact on quality of life (QOL). The symptoms are often ascribed to osteoarthritis (OA), for which the standard treatment is systemic anti-inflammatories, but pharmacologic intervention can have significant short-term and long-term side effects.

OBJECTIVES

Test the efficacy of a Food and Drug Administration (FDA)-cleared pulsed shortwave therapy (PSWT) device as a means to modulate vagus nerve activity and initiate a systemic anti-inflammatory response to determine its ability to improve functionality and the QOL of canines with inflammatory symptoms commonly associated with OA.

METHODS

A randomized, double-blinded, placebo-controlled 14-day study of 60 dogs with a presumptive prior diagnosis of OA in at least one limb joint. Two outcomes assessing changes in the dog's QOL and functionality were measured: subjectively determined changes in eight behaviours associated with discomfort and objectively determined changes in passive range of motion (PROM). The device was secured near the cervico-thoracic region of the dog's spine. PROM measures were taken at baseline and at the end of study. Behavioural measures were taken daily.

RESULTS

Forty-nine animals completed the study. No negative side effects were reported. Average subjective discomfort scores for the treatment group (N = 26) were reduced from 3.74 to 2.10 (44%), compared to no improvement in the placebo group (N = 23) over the study period (p = 0.0001). Average PROM scores increased by 5.51 (4.59-6.23) degrees relative to the placebo group (p < 0.01). Ninety-six per cent of the treatment group showed either increased PROM or improved behavioural changes or both, compared to 4% for the placebo group (p < 0.01). Most changes occurred within the first 8 days of treatment.

CONCLUSIONS

PSWT applied at the level of the cervico-thoracic spine to target the vagus nerve may have the potential to improve QOL in dogs manifesting behaviours commonly associated with OA.

Outcome of surgical correction of medial patellar luxation in dogs weighing less than 10 kg

BACKGROUND

Various trochleoplasty techniques, including trochlear wedge recession (TWR) and trochlear block recession (TBR), are used to treat dogs with medial patellar luxation (MPL). However, the objective outcomes of these surgical procedures are underreported.

METHODS

Medical records were obtained for dogs weighing less than 10 kg that underwent either TWR or TBR and tibial tuberosity transposition to address grade I-III MPL. Long-term (at least 1 year after the last procedure) follow-up included orthopaedic and radiographic examinations, such as osteoarthritis score (OAS), ground reaction force (GRF) analysis and canine brief pain inventory (CBPI).

RESULTS

Overall, 20 dogs (26 stifles) were followed up in the long term. Minor postoperative complications, medial patellar reluxation (MPR) and intermittent lameness occurred in 46.15%, 19.23% and 15% of the dogs, respectively. MPR occurred only in TWR-treated stifles, while mean OAS increased in all groups. Using the CBPI, the owners perceived an excellent or very good outcome in 95% of dogs.

LIMITATIONS

The limitations of the study include its retrospective observational nature, a lack of randomisation and a small sample size.

CONCLUSION

Surgical treatment resulted in a favourable outcome. GRF analysis could detect subtle differences in weight bearing in dogs treated for MPL, which might not be apparent clinically. There might be a higher risk for reluxation for TWR. However, a larger-scale prospective study would be required to find which treatment is superior.

Quantitative sensory testing in canine musculoskeletal pain: Findings from a systematic review, meta-analysis feasibility assessment, and limitations

Quantitative sensory testing (QST) allows the study of pain mechanisms, patient phenotyping, and response to therapy. The goals of this study were to conduct a systematic review of the use of QST in dogs with musculoskeletal disease including osteoarthritis (OA), and to assess, by means of a meta-analysis, the ability of QST to differentiate affected dogs from healthy controls. The study protocol was registered; three bibliographic databases were screened. Studies involving QST in healthy dogs and those with musculoskeletal disease were included. Data were extracted using a standardized form. Assessment of quality and risk of bias were performed using the CAMARADES critical assessment tool. Twenty-nine articles met the inclusion criteria [systematic review (n = 11); meta-analysis (n = 28)]. In the systematic review, ten studies performed static QST: mechanical [punctate tactile (n = 6); mechanical pressure (n = 5)]; thermal [cold (n = 3); hot (n = 4)]; electrical (n = 1); and one study performed dynamic QST [conditioned pain modulation (n = 1)]. Most studies were of good scientific quality and showed low to moderate risk of bias. A meta-analysis was not possible due to numerous and severe issues of heterogeneity of data among studies. Methods to reduce risk of bias and use of reporting guidelines are some of the most needed improvements in QST research in dogs. Standardization of QST methodology is urgently needed in future studies to allow for data synthesis and a clear understanding of the sensory phenotype of dogs with and without chronic pain including OA.

Effect of intra-articular platelet-rich plasma or hyaluronic acid on limb function recovery in dogs with TPLO for cranial cruciate ligament rupture: a randomised controlled trial

OBJECTIVES

This study aimed to investigate the recovery of limb function following a single intra-articular injection of platelet-rich plasma or hyaluronic acid in dogs with cranial cruciate ligament rupture treated with tibial plateau levelling osteotomy compared to dogs receiving no injection intraoperatively.

MATERIALS AND METHODS

Sixty-two dogs with cranial cruciate ligament rupture, body weights of 20 to 40 kg, and no other orthopaedic conditions were enrolled in this prospective, randomised, double-blind, controlled study at the small animal clinic at LMU Munich. All dogs underwent tibial plateau levelling osteotomy. Based on random allocation, they received either a single intra-articular injection of platelet-rich plasma, hyaluronic acid or no injection intraoperatively. Gait analysis, clinical examinations, radiography of the stifle joint for osteoarthritis progression and two validated owner questionnaires were compared among groups at three timepoints postoperatively (6 weeks, 3 and 6 months). Limb function was primarily assessed by measuring the ground reaction forces.

RESULTS

At all times postoperatively, no differences were observed among groups regarding clinical examinations, osteoarthritis score values, ground reaction forces or owner questionnaires. All dogs showed significant improvement in limb function clinically, in all ground reaction forces and in the validated questionnaires. Osteoarthritis progressed minimally during rechecks in all dogs regardless of the additional injection or not.

CLINICAL SIGNIFICANCE

All dogs treated with tibial plateau levelling osteotomy for cranial cruciate ligament rupture showed improvements in limb function. No additive effect on faster recovery was demonstrated with the additional intra-articular injection of platelet-rich plasma or hyaluronic acid. Addition of platelet-rich plasma/hyaluronic acid injections during tibial plateau levelling osteotomy is unnecessary considering the lack of benefit observed up to 6 months postoperatively.

Magnetic collars improve owner-reported pain scores in dogs with osteoarthritis in a blinded crossover study

OBJECTIVE

To investigate changes in owner-reported pain, interference of pain on function, and quality of life (QOL) in dogs with clinically suspected osteoarthritis when wearing a collar containing a static magnet.

ANIMALS

16 dogs over 5 years old weighing between 10 and 40 kg with a clinical diagnosis of osteoarthritis and on stable treatment.

METHODS

A prospective, blinded crossover study in which dogs wore a collar containing a static magnet or placebo for two 4-week study arms separated by a 2-week washout period. Clients completed the Canine Brief Pain Inventory prior to collar placement and then weekly throughout each arm. Changes in QOL, pain severity, and pain interference scores from the beginning to the end of these arms and changes between the arms were calculated and analyzed using Wilcoxon signed rank tests.

RESULTS

40% of included dogs were on stable doses of NSAIDs. The pain severity scores (PSS), pain interference scores (PIS), and QOL scores were not significantly different at the start of the arms. There was no significant change in PSS or PIS from the start to end of the placebo arms (median changes, 0 and -0.1). Both PSS and PIS reduced significantly during the magnet arms (median changes, -1.0 and -1.2, respectively). The QOL scores did not change significantly in either arm (median changes, 0 and 0).

CLINICAL RELEVANCE

This preliminary study suggests that magnetic collars reduce owner-reported pain severity and pain interference on function in dogs with clinically suspected osteoarthritis, and further, larger investigations are now warranted.

Spatial working memory in a disappearing object task is impaired in female but not male dogs with chronic osteoarthritis

Chronic pain in humans is associated with impaired working memory but it is not known whether this is the case in long-lived companion animals, such as dogs, who are especially vulnerable to developing age-related chronic pain conditions. Pain-related impairment of cognitive function could have detrimental effects on an animal's ability to engage with its owners and environment or to respond to training or novel situations, which may in turn affect its quality of life. This study compared the performance of 20 dogs with chronic pain from osteoarthritis and 21 healthy control dogs in a disappearing object task of spatial working memory. Female neutered osteoarthritic dogs, but not male neutered osteoarthritic dogs, were found to have lower predicted probabilities of successfully performing the task compared to control dogs of the same sex. In addition, as memory retention interval in the task increased, osteoarthritic dogs showed a steeper decline in working memory performance than control dogs. This suggests that the effects of osteoarthritis, and potentially other pain-related conditions, on cognitive function are more clearly revealed in tasks that present a greater cognitive load. Our finding that chronic pain from osteoarthritis may be associated with impaired working memory in dogs parallels results from studies of human chronic pain disorders. That female dogs may be particularly prone to these effects warrants further investigation.

microRNAs are differentially expressed in equine plasma of horses with osteoarthritis and osteochondritis dissecans versus control horses

Osteoarthritis (OA) is a leading cause of lameness in horses with no effective disease-modifying treatment and challenging early diagnosis. OA is considered a disease of the joint involving the articular cartilage, subchondral bone, synovial membrane, and ligaments. Osteochondritis dissecans (OCD) is a joint disease consisting of focal defects in the osteochondral unit which may progress to OA later in life. MicroRNAs (miRNAs) have been recognized as small non-coding RNAs that regulate a variety of biological processes and have been detected in biological fluids. MiRNAs are currently investigated for their utility as biomarkers and druggable targets for a variety of diseases. The current study hypothesizes that miRNA profiles can be used to actively monitor joint health and differences in miRNA profiles will be found in healthy vs diseased joints and that differences will be detectable in blood plasma of tested horses. Five horses with OA, OCD, and 4 controls (C) had blood plasma and synovial fluid collected. Total RNA, including miRNA was isolated before generating miRNA libraries from the plasma of the horses. Libraries were sequenced at the Schroeder Arthritis Institute (Toronto). Differential expression analysis was done using DESeq2 and validated using ddPCR. KEGG pathway analysis was done using mirPath v.3 (Diana Tools). 57 differentially expressed miRNAs were identified in OA vs C plasma, 45 differentially expressed miRNAs in OC vs C plasma, and 21 differentially expressed miRNAs in OA vs OCD plasma. Notably, miR-140-5p expression was observed to be elevated in OA synovial fluid suggesting that miR-140-5p may serve as a protective marker early on to attenuate OA progression. KEGG pathway analysis of differentially expressed plasma miRNAs showed relationships with glycan degradation, glycosaminoglycan degradation, and hippo signaling pathway. Interestingly, ddPCR was unable to validate the NGS data suggesting that isomiRs may play an integral role in miRNA expression when assessed using NGS technologies.

Comparative study of 1H-NMR metabolomic profile of canine synovial fluid in patients affected by four progressive stages of spontaneous osteoarthritis

The study aimed to assess the metabolomic profile of the synovial fluid (SF) of dogs affected by spontaneous osteoarthritis (OA) and compare any differences based on disease progression. Sixty client-owned dogs affected by spontaneous OA underwent clinical, radiographic, and cytologic evaluations to confirm the diagnosis. The affected joints were divided into four study groups based on the Kallgreen-Lawrence classification: OA1 (mild), OA2 (moderate), OA3 (severe), and OA4 (extremely severe/deforming). The osteoarthritic joint's SF was subjected to cytologic examination and 1H-NMR analysis. The metabolomic profiles of the study groups' SF samples were statistically compared using one-way ANOVA. Sixty osteoarthritic joints (45 stifles, 10 shoulders and 5 elbows) were included in the study. Fourteen, 28, and 18 joints were included in the OA1, OA2, and OA3 groups, respectively (0 joints in the OA4 group). Metabolomic analysis identified 48 metabolites, five of which were significantly different between study groups: Mannose and betaine were elevated in the OA1 group compared with the OA2 group, and the 2-hydroxyisobutyrate concentration decreased with OA progression; in contrast, isoleucine was less concentrated in mild vs. moderate OA, and lactate increased in severe OA. This study identified different 1H-NMR metabolomic profiles of canine SF in patients with progressive degrees of spontaneous OA, suggesting 1H-NMR metabolomic analysis as a potential alternative method for monitoring OA progression. In addition, the results suggest the therapeutic potentials of the metabolomic pathways that involve mannose, betaine, 2-hydroxyisobutyrate, isoleucine, and lactate.

Prevalence of radiographic appendicular osteoarthritis and associated clinical signs in young dogs

This study aimed to determine the prevalence of osteoarthritis (OA) and associated clinical signs in young dogs. Owners of dogs aged 8 months-4 years from a single practice, were contacted in random order, to participate in a general health screen. Clinical and orthopedic examinations were performed. Each joint was scored for pain reactions (0-4). Orthogonal radiographs of all joints were made under sedation. Each joint was scored for radiographic OA (rOA) severity on an 11-point scale. Clinical OA (cOA) was defined as an overlap of rOA and joint pain in ≥ 1 joint. Owners completed OA questionnaires. The owners of 123 dogs agreed to participate. Overall, 39.8% (49/123) of dogs had rOA in ≥ 1 joint, and 16.3% (20/123) or 23.6% (29/123) dogs had cOA, depending on the cut-off value of joint pain; moderate (2), or mild (1), respectively. Owners of dogs with cOA observed signs of impairment in approximately 30% of cases. Only 2 dogs with cOA were receiving OA pain management. The most commonly affected joints in descending order of frequency were elbow, hip, tarsus, and stifle. Radiographically visible OA is common in young dogs, and 40-60% of dogs with rOA had cOA. However, OA-pain appears underdiagnosed and undertreated in young dogs.

Evaluation of subchondral bone cysts in canine elbows with radiographic osteoarthritis secondary to elbow dysplasia

OBJECTIVE

To investigate whether subchondral bone cysts (SBCs) were present in dogs with radiographic elbow osteoarthritis (OA) and to investigate their relationship with radiographic OA severity.

STUDY DESIGN

Retrospective cross-sectional study.

SAMPLE POPULATION

Thirty-eight Labrador retrievers (total of 76 elbows).

METHODS

Elbow computed tomography (CT) images of 18 young (≤2 years old) and 20 old (>2 years old) Labrador retrievers, which presented for elbow-associated lameness, were reviewed. Radiographic elbow OA was graded into four groups based on the largest osteophyte size on CT. The presence, number, and maximum diameter of SBCs were determined.

RESULTS

Subchondral bone cysts were only identified in elbows with osteophytic new bone formation. The number and size of SBCs were associated with radiographic OA severity (p < .001 and p = .041 respectively). Specifically, the rate at which SBCs were present increased for both moderate and severe OA in comparison with the mild OA (moderate OA RR = 2.46, 95% CI 2.08-2.92, p < .001; severe OA RR = 5.60, 95% CI 4.79-6.55, p < .001). For dogs with severe OA, there was an increased likelihood that their SBCs were larger than SBCs from dogs with mild OA (OR = 1.056, 95% CI 1.012-1.101, p = .012). No SBCs were observed in elbows without radiographic evidence of OA.

CONCLUSION

Subchondral bone cysts were identified as a feature of radiographic elbow osteoarthritis in Labrador retrievers, and their number and size were indicative of the presence and severity of radiographic elbow OA.

CLINICAL SIGNIFICANCE

Subchondral bone cysts are a potential imaging biomarker for quantitative assessment for canine OA.

Quantifying the Stress in Stress Radiographs to Determine Sufficient Laxity of the Coxofemoral Joint: A Canine Hip Dysplasia Cadaveric Study

OBJECTIVE

 While it has been known for a long time that laxity in the hip joint is the primary cause of degenerative changes later on in canine hip dysplasia, limited data are available on the fundamental characteristics that define the procedure used to quantify this. The aim of this study was to evaluate the force-laxity relation to assess the repeatability of repeated cycles of stress on the hip joint and determine the force necessary tomeasure a sufficient proportion of laxity present in hip joints.

MATERIALS AND METHODS

 Thirty-four canine cadavers underwent a radiographic protocol including stress radiographs with increasing force using the Vezzoni modified Badertscher distension measuring device (VMBDmD). Three dogs underwent five repeat examinations. The laxity index (LI) and osteoarthritis were scored.

RESULTS AND CONCLUSION

 The curves and the maximal LI (LImax) were not significantly influenced by osteoarthritis, weight, gender, and side. The position of the VMBDmD influenced the curve but not the LImax. The force-laxity curve itself and the LImax were repeatable, which indicated that it did not cause permanent damage to the joint and also confirmed the practicability of the procedure. Ninety percent of hip joints reached sufficient laxity at a force of 95.32 N, which is realistically achievable. Further studies are necessary before extrapolating these results to patients and to further enlighten the biomechanics of stress radiographs.

Current evidence for non-pharmaceutical, non-surgical treatments of canine osteoarthritis

Osteoarthritis is a progressive degenerative disease process that affects a significant proportion of the canine population, impacting these animals' quality of life. Currently, there is no cure and treatment consists of managing the clinical signs of pain and reduced mobility. There are many treatments for canine osteoarthritis and in this review we discuss the evidence base behind non-pharmaceutical, non-surgical treatments of this disease. These treatments include weight management, nutraceuticals, acupuncture, physiotherapies such as therapeutic exercise, hydrotherapy as well as other therapeutic modalities including photobiomodulation therapy, electromagnetic field therapy and others.

Therapeutic applications of canine platelets and their derivatives: a narrative review

Platelets contain a multitude of growth factors and play a crucial role in physiological processes such as thrombogenesis, tissue repair, and angiogenesis. As a result, platelet-derived products have significant potential for efficient utilization in the realm of regenerative medicine due to their therapeutic and biological attributes. Numerous studies have already substantiated the therapeutic viability of platelets in various canine ailments. The existing literature indicates a substantial surge in the clinical application of canine platelets, positioning platelet-derived products as a viable alternative to conventional therapeutic agents. Platelet concentrates, including platelet-rich plasma and platelet-rich fibrin are commonly used as a therapeutic modality in clinical cases. These therapeutic derivatives exhibit effectiveness in tissue regeneration and can serve as complementary therapies. Notably, they offer a cost-effective and easily accessible therapeutic option, which has demonstrated its benefits in chronic inflammatory disorders such as osteoarthritis and tendinitis, ophthalmic conditions, wound healing, and mandibular injuries in canine patients. The broad spectrum of therapeutic effects displayed by platelets is providing researchers with novel perspectives for crafting therapeutic models in future investigations. This review centers on exploring the therapeutic potential of canine platelets across diverse disorders. Further exploration into platelet products, encompassing their preparation and applicability in canine medicine, is imperative. These inquiries hold the promise of unveiling fresh horizons for the domain of regenerative medicine.

GenPup-M: A novel validated owner-reported clinical metrology instrument for detecting early mobility changes in dogs

OBJECTIVE

To use a previously validated veterinary clinical examination sheet, Liverpool Osteoarthritis in Dogs (LOAD) questionnaire, combined with kinetic and kinematic gait analysis in dogs with/without mobility problems to demonstrate the capacity of a novel clinical metrology instrument ("GenPup-M") to detect canine mobility impairments.

DESIGN

Quantitative study.

ANIMALS

62 dogs (31 with mobility impairments and 31 without mobility impairments).

PROCEDURE

The dogs' clinical history was obtained from owners and all dogs underwent a validated orthopaedic clinical examination. Mobility impairments were diagnosed in the mobility impaired group based on clinical history and orthopaedic examination. Owners were asked to complete GenPup-M along with a previously validated mobility questionnaire (Liverpool Osteoarthritis in Dogs (LOAD)) to identify construct validity. As a test of criterion validity, the correlation between instrument scores and the overall clinical examination scores, along with force-platform obtained peak vertical forces (PVF) were calculated. GenPup-M underwent internal consistency and factor analysis. Spatiotemporal parameters were calculated for dogs with/without mobility impairments to define the gait differences between these two groups.

RESULTS

Principal Component Analysis identified GenPup-M had two components with Eigenvalues >1 ("stiffness/ease of movement" and "willingness to be active/exercise"). Cronbach's α was used to test internal consistency of GenPup-M and was found to be "good" (0.87). There was a strong, positive correlation between GenPup-M and LOAD responses (r2 = 0.69, p<0.001) highlighting construct validity. Criterion validity was also shown when comparing GenPup-M to clinical examination scores (r2 = 0.74, p<0.001) and PVF (r2 = 0.43, p<0.001). Quantitative canine gait analysis showed that there were statistically significant differences between peak vertical forces (PVF) of mobility impaired and non-mobility impaired dogs (p<0.05). Analyses of PVF showed that non-mobility impaired dogs more evenly distributed their weight across all thoracic and pelvic limbs when compared to mobility impaired dogs. There were also consistent findings that mobility impaired dogs moved slower than non-mobility impaired dogs.

CONCLUSION AND CLINICAL RELEVANCE

GenPup-M is a clinical metrology instrument (CMI) that can be completed by dog owners to detect all mobility impairments, including those that are early in onset, indicating the versatility of GenPup-M to assess dogs with and without mobility impairments. Results of the study found that GenPup-M positively correlated with all three objective measures of canine mobility and consequently showed criterion and construct validity. Owner-reported CMIs such as GenPup-M allow non-invasive scoring systems which veterinary surgeons and owners can use to allow communication and longitudinal assessment of a dog's mobility. It is anticipated that GenPup-M will be used by owners at yearly vaccinations/health checks, allowing identification of any subtle mobility changes, and enabling early intervention.

Equine Bone Marrow Aspirate Concentrate

Bone marrow concentrate is generated by centrifugation of bone marrow aspirate. It contains mesenchymal stromal cells, anabolic chemokines/cytokines, and supraphysiological concentrations of interleukin-1 receptor antagonist protein (IL-1RA). It is an effective treatment for osteoarthritis or desmitis, or as an adjunct in surgery to enhance bone or cartilage repair.

Recall Bias in Client-Reported Outcomes in Canine Orthopaedic Patients Using Clinical Metrology Instruments

OBJECTIVE

 The aim of this study was to determine the accuracy of client recollection of their dogs' preconsultation status using clinical metrology instruments such as the Liverpool Osteoarthritis in Dogs (LOAD) and Canine Brief Pain Inventory (CBPI) questionnaires in dogs presenting to a referral orthopaedic clinic.

STUDY DESIGN

 This is a longitudinal prospective cohort study of client-owned dogs presenting for investigations of lameness (n = 217). LOAD and CBPI questionnaires were completed by the owners at the first consultation (T0). Owners were contacted at 2 (T1), 6 (T2), and 12 (T3) months and asked to recall their dogs' T0 status by completing another LOAD and CBPI questionnaire. The agreement between the T0 and recalled LOAD and CBPI scores was determined using the two-way mixed effects intraclass correlation coefficient (ICC). The Wilcoxon signed-rank test was used to determine the difference between scores.

RESULTS

 For the LOAD scores, there was moderate agreement between T0 and T1 (ICC: 0.64) and T0 and T2 (ICC: 0.53) scores and poor agreement between T0 and T3 (ICC: 0.496). For the CBPI Pain Severity Scores, there was poor agreement between T0 and all three subsequent time points (ICC < 0.5). For the CBPI Pain Interference Scores, there was moderate agreement between T0 and T1 (ICC: 0.57) and T2 (ICC: 0.56) scores and poor agreement between T0 and T3 (ICC: 0.43).

CONCLUSION

 The LOAD and CBPI questionnaires are subject to recall bias. Studies reporting retrospectively acquired CMI data should be interpreted with caution.

Long-term outcomes in dogs with elbow dysplasia, assessed using the canine orthopaedic index

BACKGROUND

Elbow dysplasia (ED) is an important cause of lameness in dogs. This study aimed to report long-term outcomes in dogs with elbow osteoarthritis.

METHODS

Demographic data, medical management, and scores from The American College of Veterinary Surgeons' Canine Orthopaedic Index (COI) were collected from owners of dogs radiographically screened for ED, graded as normal, mild, or moderate. Telephone interviews were performed in 2017 (Q1), followed by an email survey in 2020 (Q2). The association between ED grade and deterioration in COI scores over time was evaluated with logistic regression.

RESULTS

A total of 765 replies were collected for Q1 and 293 for Q2. At Q2, 222 dogs (76%) were alive, with a median age of 8 years (range 5-12 years). No association was found between ED and changes in COI score over time or between ED and survival (p = 0.071). Dogs with mild and moderate ED were treated with analgesic medications to a higher degree than dogs without ED (p < 0.05).

LIMITATIONS

Only owner-assed data were assessed; no clinical orthopaedic examination or follow-up radiographic evaluation was performed.

CONCLUSIONS

No association was found between the grade of ED and the worsening of clinical signs in dogs with elbow osteoarthritis.

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.

Pro-Inflammatory Cytokine Priming and Purification Method Modulate the Impact of Exosomes Derived from Equine Bone Marrow Mesenchymal Stromal Cells on Equine Articular Chondrocytes

Osteoarthritis (OA) is a widespread osteoarticular pathology characterized by progressive hyaline cartilage degradation, exposing horses to impaired well-being, premature career termination, alongside substantial financial losses for horse owners. Among the new therapeutic strategies for OA, using mesenchymal stromal cell (MSC)-derived exosomes (MSC-exos) appears to be a promising option for conveying MSC therapeutic potential, yet avoiding the limitations inherent to cell therapy. Here, we first purified and characterized exosomes from MSCs by membrane affinity capture (MAC) and size-exclusion chromatography (SEC). We showed that intact MSC-exos are indeed internalized by equine articular chondrocytes (eACs), and then evaluated their functionality on cartilaginous organoids. Compared to SEC, mRNA and protein expression profiles revealed that MAC-exos induced a greater improvement of eAC-neosynthesized hyaline-like matrix by modulating collagen levels, increasing PCNA, and decreasing Htra1 synthesis. However, because the MAC elution buffer induced unexpected effects on eACs, an ultrafiltration step was included to the isolation protocol. Finally, exosomes from MSCs primed with equine pro-inflammatory cytokines (IL-1β, TNF-α, or IFN-γ) further improved the eAC hyaline-like phenotype, particularly IL-1β and TNF-α. Altogether, these findings indicate the importance of the exosome purification method and further demonstrate the potential of pro-inflammatory priming in the enhancement of the therapeutic value of MSC-exos for equine OA treatment.

Evaluation of the hoof centre-of-pressure path in horses affected by chronic osteoarthritic pain

INTRODUCTION

The Centre of Pressure (COP) is the single point summarising all forces transferred to the hoof during the stance phase of a stride. COP path (COPp) is the trajectory that COP follows from footstrike to lift-off. Aim of the present study was to characterize the COP and COPp in horses affected by osteoarthritis and chronic lameness.

MATERIALS AND METHODS

Seventeen adult horses with a diagnosis of osteoarthritis and single limb chronic lameness were recruited. The COP was recorded using a wireless pressure measuring system (TekScan®) with sensors taped to the hooves (either fore- or hind limb, depending on lameness location). The COPp coordinates were further processed. Procrustes analysis was performed to assess the variability of single strides COPp and average COPp among strides, gaits, and limbs by calculating Procrustes distances (D-values). A linear mixed-effects model was run to analyse D-values differences for lame and sound limbs. Additionally, average COPp D-values and COPp hoofprint shape indices were compared for lame and sound limbs with the Signed Rank Test.

RESULTS

At walk and trot the single-stride COPp D-values were significantly lower in lame than in sound limbs (marginal effects p<0.001). Analysis of the average COPp D-values confirmed that each hoof COPp is highly consistent with itself over subsequent trials but is different from the contralateral. COPp and hoofprint shape indices did not differ between sound and lame limbs. Footstrike and lift-off within the hoofprint showed that most horses had lateral footstrike and lift-off, independently of the lameness location.

CONCLUSION

Our findings are in line with previous observations that COPp are highly repetitive and characteristic for each horse and limb. There seems to be a further decrease in COPp variability in the presence of a painful limb pathology.

A prospective, randomized, double-blind, placebo-controlled multisite, parallel-group field study in dogs with osteoarthritis conducted in the United States of America evaluating bedinvetmab, a canine anti-nerve growth factor monoclonal antibody

OBJECTIVE

Bedinvetmab, a fully canine anti-nerve growth factor monoclonal antibody, was evaluated in dogs for control of osteoarthritis-related pain in a study conducted to support registration in the USA.

STUDY DESIGN

Randomized, double-blind, placebo-controlled, multicenter, parallel-group study.

ANIMALS

General practice client-owned dogs with osteoarthritis (n = 272).

METHODS

Dogs were block randomized 1:1 to placebo (saline, n = 137) or bedinvetmab (n = 135; 0.5-1.0 mg kg-1) administered subcutaneously, once monthly. The primary end point, day 28 Canine Brief Pain Inventory (CBPI) treatment success (TS), required pain severity score (PSS; 0-10) decrease ≥1 and pain interference score (PIS; 0-10) decrease ≥ 2. CBPI TS rates [and number needed to treat (NNT)], change in scores [and standardized effect size (ES)], change in quality of life (QoL) and bedinvetmab half-life were calculated.

RESULTS

Significant (p < 0.05) improvement with bedinvetmab over placebo occurred (days 28, 42, 56, 84) for CBPI TS. Of cases evaluable for day 28 CBPI TS (placebo, n = 131; bedinvetmab, n = 128), success rates were 36.6% and 47.4%, respectively (p = 0.0410) (NNT, 9.3; PSS and PIS ES, 0.3). CBPI TS increased after the second dose in both groups, plateaued for bedinvetmab at day 42 and decreased for placebo beginning day 84. Day 84 NNT (4.3), PSS (0.4) and PIS (0.5) showed continued improvement with monthly dosing. After the first dose, mean (± standard deviation) bedinvetmab half-life was 19.1 (8.3) days. Adverse events were similar between groups and not considered treatment-related. There was a significant effect of bedinvetmab versus placebo on all CBPI components (PIS, PSS, QoL).

CONCLUSIONS AND CLINICAL RELEVANCE

These results corroborated those previously reported and provide further support of safety and effectiveness of bedinvetmab (0.5-1.0 mg kg-1) administered subcutaneously at monthly intervals to dogs for control of osteoarthritis-related pain.

A blinded, placebo-controlled study on the clinical effects of vitamin E supplementation in dogs with osteoarthritis

BACKGROUND

Vitamin E has a positive effect in the management of osteoarthritis in humans, and in a previous study of dogs. It has been suggested to decrease C-reactive protein concentrations and liver enzyme activities in humans and animals.

OBJECTIVE

To assess the effect of vitamin E supplementation on lameness, pain, pain medication requirement, clinical pathology variables, and quality of life in large-breed dogs with naturally occurring osteoarthritis.

ANIMALS

Fifty-seven client-owned dogs with naturally occurring osteoarthritis.

METHODS

Dogs received either vitamin E or placebo for 90 days in a randomized, placebo-controlled, double-blinded, prospective clinical trial. Clinical lameness scores, pain medication requirements, and owner questionnaires were used to assess response to treatment every 30 days. Blood samples were collected at enrollment and at the end of the study period.

RESULTS

Vitamin E administration did not improve pain, lameness, or quality of life as assessed by owners and veterinarians. Vitamin E supplementation did not decrease the requirement for rescue pain relief. No changes in clinical pathology variables were observed after 90 days of vitamin E supplementation. Body weight was negatively associated with the lameness scores and requirement for rescue pain relief.

CONCLUSION

Vitamin E supplementation did not have any observable positive effects in dogs with naturally occurring osteoarthritis.

Pharmacokinetics of a single oral dose of grapiprant in juvenile pigs (Sus scrofa domestica)

Both pet and research pigs can suffer from some degree of pain from surgery, injuries, or osteoarthritis (OA). Despite this, there is a paucity of data on safe and effective analgesia agents in pigs. Grapiprant is an EP4 antagonist that blocks the action of the pro-inflammatory prostanoid, PGE2 . It has shown efficacy in attenuating pain associated with ovariohysterectomy and OA in dogs. However, there are no data regarding grapiprant in pigs. Therefore, the pharmacokinetic profile of orally administered grapiprant to juvenile pigs (Sus scrofa domestica) was evaluated in this study. Seven juvenile pigs received 12 mg/kg grapiprant orally. Blood was collected from an indwelling jugular catheter using the push-pull method at set timepoints up to 48 hours. Sample analysis was performed with high-performance liquid chromatography. Mean grapiprant plasma concentration was 164.3 ± 104.7 ng/mL which occurred at 0.8 ± 0.3 h. This study demonstrated that grapiprant concentrations consistent with analgesia in dogs were reached at this dosage in pigs. Further studies are needed to evaluate the efficacy of grapiprant in pigs.

T2 mapping of cartilage in the equine distal interphalangeal joint with corresponding histology using 0.27 T and 3.0 T magnetic resonance imaging

BACKGROUND

Low-field magnetic resonance imaging (MRI) is widely available to equine veterinarians yet is insensitive at detecting cartilage damage in the distal interphalangeal joint (DIPJ). T2 mapping is a quantitative imaging technique that can detect cartilage damage before morphological change is apparent.

OBJECTIVES

Validation of a T2 mapping sequence on a low-field MR system. Correlation of the mean T2 relaxation time in sections of cartilage with varying levels of pathology using low- and high-field MRI.

STUDY DESIGN

Cross-sectional study.

METHODS

Eight phantoms with known (nominal) T2 values underwent low-field (0.27 T) MRI and 38 ex vivo DIPJs were imaged. A further 9 ex vivo DIPJs were imaged on both the low- and high-field MR systems. Immediately after imaging, the DIPJs were disarticulated and samples collected for histology. Histological sections were graded using the Osteoarthritis Research Society International (OARSI) scoring system. Fiji ImageJ software with the MRIAnalysisPak plugin was used to calculate T2 maps and draw the regions of interest (ROIs).

RESULTS

There was close agreement between the nominal and the measured T2 values in the phantom study. Spearman's rank correlation demonstrated significant positive correlation between low- and high-field T2 measurements, rho 0.644 (p < 0.001). The intrarater agreement for T2 measurements was excellent, intraclass correlation coefficient (ICC) = 0.99 (95% confidence interval [CI] = 0.99-1.00), the inter-rater agreement was excellent, ICC = 0.88 (95% CI = 0.82-0.92) and there was good intrarater agreement for OARSI scores (к = 0.76).

MAIN LIMITATIONS

Only a small number of histological samples were analysed. Both articular cartilage surfaces were measured within the ROI. There were no OARSI grade 0 control samples.

CONCLUSIONS

A T2 mapping sequence on a low-field 0.27 T MR system was validated. There was a positive correlation between low- and high-field T2 measurements. The findings suggest a higher mean T2 relaxation time in pathological cartilage tissue examined in this study compared to normal equine cartilage tissue.

Long-term outcome of dogs treated by surgical debridement of proximal humeral osteochondrosis

OBJECTIVE

To evaluate long-term clinical outcomes of dogs surgically treated for proximal humeral osteochondrosis (OC).

STUDY DESIGN

Cross-sectional study.

SAMPLE POPULATION

Twenty dogs (n = 26 shoulders).

METHODS

Dogs treated with surgical debridement of proximal humeral OC lesions >12 months prior were enrolled. Orthopedic examination (including limb circumference and shoulder goniometry), kinetic gait analysis, shoulder radiographs, shoulder computed tomography (CT), and shoulder arthroscopy were performed. All owners completed a dog mobility questionnaire.

RESULTS

Brachial circumference (P = .003) and maximum shoulder extension (P = .013) were decreased and maximum shoulder flexion (P = .008) was increased (ie less flexion) in the OC limb versus the contralateral limb in unilaterally affected dogs. There were no differences in peak vertical force and vertical impulse between affected and unaffected limbs. Dogs demonstrated a 4.4% decrease in load distributed to the operated limb. Osteoarthritis was present in all shoulders treated for OC lesions. The degree of osteoarthritis in OC-affected shoulders was increased compared to the contralateral limb as evaluated on CT (P = .005) and radiography (P = .0001) in unilaterally affected cases. Moderate-to-severe synovitis was seen in all OC-affected joints. Arthroscopically, all lesions were noted to have patchy, incomplete cartilaginous infilling. Median of aggregate Liverpool Osteoarthritis in Dogs (LOAD) scores was 6.

CONCLUSION

All dogs exhibited ipsilateral muscle atrophy and progressive osteoarthritis, with most dogs exhibiting subtle lameness on the subjective gait examination. Despite this, owner-perceived mobility was satisfactory.

CLINICAL SIGNIFICANCE

Progression of joint disease over time should be expected; however, the abnormalities detected on examination appear to be of questionable clinical relevance.

The effect of exercise on cytokine concentration in equine autologous conditioned serum

BACKGROUND

Autologous conditioned serum (ACS) is a commonly administered intra-articular treatment for the management of osteoarthritis in athletic horses.

OBJECTIVES

To investigate the influence of exercise on the concentration of cytokines in a non-commercial method of ACS production.

STUDY DESIGN

Non-randomised cross over design.

METHODS

Whole blood was obtained from eight healthy Standardbred horses immediately prior to, 1 h and 24 h following a single bout of exhaustive exercise. Blood was processed using a non-commercial method of ACS production. Fluorescent microsphere immunoassay (FMIA) analysis was performed to quantify Interleukin 1 receptor antagonist (IL-1Ra), Interleukin-10 (IL-10), Interleukin 1β (IL-1β) and tumour necrosis factor α (TNF-α) concentrations at each time point. Mixed effect repeated measures analysis of variance (ANOVA) was used to compare the pre-exercise and post-exercise cytokine concentrations. Significance was set at P < 0.05.

RESULTS

A reduced concentration of IL-1Ra (median 584.4, IQR 81.9-5098 pg/ml, p = 0.004) and an increased concentration of TNF-α (11.92, 9.28-39.75 pg/ml, P = .05) at 1 h post-exercise were observed when compared with baseline values (IL-Ra 7349, 1272-10 760 pg/ml; TNF TNF-α 11.16, 8.36-32.74 pg/ml). No difference in cytokine concentrations of IL-10 or IL-1β were found between any of the time points.

MAIN LIMITATIONS

The large biological variability and small sample size represents limitations of this study.

CONCLUSIONS

These results suggest that a single bout of intense exercise can reduce the concentration of the anti-inflammatory cytokine IL-1Ra and increase the concentration of the pro-inflammatory cytokine TNF-α, reducing the 'anti-inflammatory' cytokine composition of ACS. Our findings suggest that collection of blood for ACS production should be performed no sooner than 24 h following a single episode of intense exercise.

Teaming up to manage osteoarthritis and other chronic conditions

Knowledge of osteoarthritis (OA) will not be a prerequisite for attending a BVA Live presentation by John Innes and Robyn Lowe. Instead, they will use OA to describe a team-based approach that could be applied to the management of pretty much any long-term condition encountered in practice.

Clinical effectiveness and safety of intraarticular administration of a 117m Tin radiocolloid (Synovetin OATM ) for treatment of early and intermediate grade osteoarthritis of the elbow in a dose finding study conducted in 44 dogs

Osteoarthritis of the elbow joint secondary to elbow dysplasia is common in dogs. Intraarticular radionuclide injection is thought to suppress both synovitis and inflammatory pain mediators in the joint which are not directly addressed by current treatments. This dose-finding investigation was a longitudinal, prospective, experimental parallel group, post-test study with repeated measures. Forty-four dogs, with low to intermediate-grade osteoarthritis, received a single injection into their most clinically affected elbow joint and were randomized into three treatment cohorts; 37 MBq, 64.75 MBq, or 92.5 MBq (normalized to the body surface area of a 22 kg dog) of 117m Sn radiocolloid. Dogs were assessed monthly by owners, using the canine Brief Pain Inventory (cBPI), and at 1, 3, 6, 9, and 12 months intervals by investigators. Positive responses to treatment were observed by both owners and clinicians in all dose groups with the medium dose group having the highest and most durable response rate based on cBPI scores. The results of this study support the use of 117m Sn radiocolloid as a primary treatment of osteoarthritis in low to intermediate-grade osteoarthritis of the canine elbow.

Treatment of Septic Tenosynovitis and Osteoarthritis in an American White Pekin (Anas platyrhynchos domesticus) with Repeated Intravenous Regional Limb Perfusion and Antibiotic-Impregnated Calcium Sulfate Beads

A 2-year-old female American white pekin (Anas platyrhynchos domesticus) was assessed for a 2-month history of chronic lameness and swelling involving the left leg. Radiographic images of the left leg showed soft tissue swelling of the digits and tarsometatarsus with osteolysis of the tarsometatarsal-phalangeal joint. A complete blood count revealed marked leukocytosis and hyperproteinemia. A Streptococcus species was isolated from a bacterial culture of fluid obtained from the left tarsometatarsal-phalangeal joint. Biweekly intravenous regional limb perfusions of the left leg with ampicillin-sulbactam and amikacin were performed on the patient. Despite initial improvement in left leg lameness and swelling, follow-up radiographic images showed progressive osteolysis of the tarsometatarsal-phalangeal joint and associated digits. Surgical placement of antibiotic-impregnated calcium sulfate beads into the left tarsometatarsal-phalangeal joint was next performed with concurrent, repeated intravenous regional limb perfusion using the same antibiotic. Following the placement of antibiotic-impregnated beads and continued intravenous regional limb perfusion, the duck had decreased lameness and swelling of the left leg. Repeated antibiotic treatment through intravenous regional limb perfusion and concurrent placement of antibiotic-impregnated calcium sulfate beads is a practical treatment option for complicated distal limb infections in avian species. This therapeutic protocol has great potential in treating aggressive distal leg infections in many avian species because regional limb perfusion alone may not penetrate the joint adequately to achieve complete resolution of infection.

Minimal clinically-important differences for the 'Liverpool Osteoarthritis in Dogs' (LOAD) and the 'Canine Orthopedic Index' (COI) client-reported outcomes measures

Client-reported outcomes measures (CROMs) have been previously validated for the evaluation of canine osteoarthritis. A published systematic review indicated that the 'Liverpool Osteoarthritis in Dogs' (LOAD) and the 'Canine Orthopedic Index' (COI) can be recommended for use in dogs with osteoarthritis; these CROMs have also been used in the context of measuring surgical outcomes of dogs with orthopaedic conditions. However, the minimal clinically-important differences (MCIDs) for these CROMs have not been investigated. Such estimates would be useful for investigators and regulators so that these CROMs can be used in clinical trials. Data from the RCVS Knowledge Canine Cruciate Registry were extracted, and baseline and 6 week follow-up data on dogs that had received surgery for cranial cruciate ligament rupture were used to make estimates of MCIDs using distribution-based and anchor-based methods. Data from 125 dogs were categorised based on the anchor question and LOAD and COI scores analysed accordingly. The four anchor-based methods provided a range of MCIDs for each CROM (1 to 8.8 for LOAD and 3.5 to 17.6 for COI). In the two different distribution-based methods, the MCIDs for LOAD ranged from 1.5 (effect size) to 2.4 (standard error of measurement) and the effect size method yielded a result of 2.2 for COI. The results showed that the value of the MCIDs depended on the method that was applied. Receiver operator characteristic curves provided areas under the curve (AUCs) greater than 0.7, which indicated that the cut-off point was acceptable; LOAD had the greater AUC at 0.867. In summary, the authors currently recommend a MCID of '4' for LOAD and '14' for COI although further work in other clinical contexts (such as osteoarthritis associated with chronic pain) is required to add confidence to these estimates. For the first time, we have provided estimates for MCIDs for these two CROMs which will facilitate sample size estimates in future clinical studies that use these CROMs as outcomes measures.

Characterization of the Proteins Secreted by Equine Muscle-Derived Mesenchymal Stem Cells Exposed to Cartilage Explants in Osteoarthritis Model

BACKGROUND

Osteoarthritis (OA) is a highly prevalent joint degenerative disease for which therapeutic treatments are limited or invasive. Cell therapy based on mesenchymal stem/stromal cells (MSCs) is therefore seen as a promising approach for this disease, in both human and horses. As the regenerative potential of MSCs is mainly conferred by paracrine function, the goal of this study was to characterize the secreted proteins of muscle-derived MSCs (mdMSCs) in an in vitro model of OA to evaluate the putative clinical interest of mdMSCs as cell therapy for joint diseases like osteoarthritis.

METHODS

An equine osteoarthritis model composed of cartilage explants exposed to pro-inflammatory cytokines was first developed. Then, the effects of mdMSC co-culture on cartilage explant were studied by measuring the glycosaminoglycan release and the NO₂^- production. To identify the underlying molecular actors, stable isotope-labeling by amino acids in cell culture based secreted protein analyses were conducted, in the presence of serum. The relative abundance of highly sequenced proteins was finally confirmed by western blot.

RESULTS

Co-culture with muscle-derived MSCs decreases the cytokine-induced glycosaminoglycan release by cartilage explants, suggesting a protecting effect of mdMSCs. Among the 52 equine proteins sequenced in the co-culture conditioned medium, the abundance of decorin and matrix metalloproteinase 3 was significantly modified, as confirmed by western blot analyses.

CONCLUSIONS

These results suggest that muscle-derived MSCs could reduce the catabolic effect of TNFα and IL-1β on cartilage explant by decreasing the secretion and activity of matrix metalloproteinase 3 and increasing the decorin secretion. mdMSCs capacity to reduce the catabolic consequences of cartilage exposure to pro-inflammatory cytokines. These effects can be explained by mdMSC-secreted bioactive such as TIMP-1 and decorin, known as an inhibitor of MMP3 and an anti-inflammatory protein, respectively.

RELATIONSHIP BETWEEN REPRODUCTIVE AND BONE BIOMARKERS AND OSTEOARTHRITIS IN ZOO ASIAN (ELEPHAS MAXIMUS) AND AFRICAN (LOXODONTA AFRICANA) ELEPHANTS

Osteoarthritis (OA) is common in zoo Asian (Elephas maximus) and African (Loxodonta africana) elephants. This study investigated the relationship between confirmed or suspected OA with ovarian cyclicity, gonadotropins, progestagens, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and collagen type I (CTX-I) in zoo elephants. In Asian elephants, odds of having confirmed or suspected OA decreased with cycling (OR = 0.22, P = 0.016; OR = 0.29, P = 0.020, respectively), however, not when adjusted for age (odds ratio [OR] = 0.31, P = 0.112; OR = 0.58, P = 0.369, respectively). In African elephants, none of the models between confirmed OA and cycling status were significant (P > 0.060), while the odds of having suspected OA decreased with cycling (OR = 0.12, P = 0.001), even after adjusting for age (OR = 0.15, P = 0.005). Progestagens (Asian elephants P > 0.096; African elephants P > 0.415), LH (Asian P > 0.129; African P > 0.359), and FSH (Asian P > 0.738; African P > 0.231) did not differ with confirmed or suspected OA status, unadjusted. CTX-I concentrations were not related to OA status (P > 0.655). This study concluded hormonal changes may not have a strong impact on OA, so additional investigation into other serologic biomarkers is warranted.

Evaluating the Safety of Intra-Articular Mitotherapy in the Equine Model: A Potential Novel Treatment for Osteoarthritis

No current treatments available halt osteoarthritis progression in horses or humans. Intra-articular injection of mitochondria is a novel treatment that has the potential to improve cell metabolism and decrease inflammation, but safety of this treatment has yet to be established in the horse. Autologous blood-derived mitochondria isolated using a commercially available kit were injected into the left carpus joint of 3 horses which were monitored for 28 days. Horses received physical examinations, video recorded gait evaluations, joint diameter measurement, synovial fluid collection, and blood collection on day 0 (baseline prior to mitotherapy, day of mitochondria injection), 1, 3, 7, 14, and 28. Systemic inflammation was assessed via complete blood count, fibrinogen, and plasma serum amyloid A (SAA). Local inflammation was assessed via synovial fluid cytology and physical examination parameters. Physical exam parameters remained stable and no joint swelling was observed after mitotherapy. No change was noted in video recorded gait evaluations as determined by a blinded evaluator. Complete blood counts revealed no significant increase in white blood cells. SAA only increased mildly in 1 horse. Fibrinogen became slightly elevated above reference range in 2 horses at day 7, but later normalized. Mild increases in synovial fluid nucleated cell counts and total protein occurred on day 1 and 3, but resolved within 7 days without intervention. Autologous mitochondria injection into the equine intercarpal joint was well tolerated with no signs of inflammation. This safety information allows for future studies evaluating mitotherapy efficacy.

Prevalence of radiographic changes in forelimb digits and metacarpophalangeal joints of South African endurance racehorses

BACKGROUND

If the number of events alone is considered, endurance riding is the fastest growing and the second-most popular Fédération Equestre Internationale (FEI) discipline. Lameness is the most common cause of elimination from endurance races worldwide. To the authors' knowledge, no studies have been published investigating the prevalence of radiographic changes in the forelimb digits and metacarpophalangeal joints (MCP) of endurance racehorses in South Africa.

OBJECTIVE

Investigate the prevalence of radiographic changes in the forelimb digits and MCP joints of South African endurance racehorses.

METHOD

One hundred endurance racehorses registered with ERASA were volunteered by their owners to partake in the current study. Radiographs were obtained from horses competing in endurance races during the 2018-2019 endurance racing season. Radiographs included seven standard views of each distal forelimb. Radiographic images were independently evaluated by three observers, point prevalence and inter-rater reliability (IRR) was calculated.

RESULTS

Data analysis of the forelimb digits revealed a large proportion of horses with bilateral signs of dorsopalmar hoof imbalance (95%); a diversion from a straight digital axis (91%), with an extended (broken back) proximal interphalangeal joint (67%) being the most common abnormality. Osteoarthritis of the proximal (16%) and distal (7%) interphalangeal joints was only observed in a low percentage of horses. Interestingly, the hoof-distal-phalanx-ratio of the majority (86%) of horses was more than 25% but none of these horses showed any other signs of chronic laminitis, indicating that hoof-distal-phalanx-ratio might not be a reliable indicator of chronic laminitis in this population of horses. Ossification of the ungular cartilages was observed in the majority (69%) of horses, either affecting one or both distal phalanges. Descriptive data analysis of the MCP joints showed that a large proportion of horses displayed radiological signs of MCP joint osteoarthritis (28%), with 10% being bilateral.

CONCLUSIONS AND CLINICAL RELEVANCE

The current study provides insight into radiographic changes and their prevalence in the distal front limbs of South African endurance racehorses. Knowledge about the prevalence of specific radiographic changes would enable equine practitioners to better evaluate and manage horses that are affected. Although no correlations were made with age, speed or number of competitive kilometres competed, the current study may serve as a basis for future research.

Evaluation of Fortetropin in geriatric and senior dogs with reduced mobility

As pets age, quality of life and mobility can be affected by pain of osteoarthritis and age-related muscle atrophy (sarcopenia). The purpose of this randomized, double-blinded, placebo-controlled study was to evaluate the effects of Fortetropin, a nonthermal-pasteurized, freeze-dried, fertilized egg yolk product, on mobility in senior dogs. Mobility scores were calculated using a standardized and validated client-based survey: the Liverpool Osteoarthritis in Dogs (LOAD) questionnaire. Results showed mild, but statistically significant, improvement of the mobility scores for the treatment group at both week 6 (P = 0.03) and week 12 (P = 0.006) compared to the baseline score. No statistical improvement was noted at any time in the placebo group or between the treatment and placebo group.

Optical photothermal infrared spectroscopy can differentiate equine osteoarthritic plasma extracellular vesicles from healthy controls

Equine osteoarthritis is a chronic degenerative disease of the articular joint, characterised by cartilage degradation resulting in pain and reduced mobility and thus is a prominent equine welfare concern. Diagnosis is usually at a late stage through clinical examination and radiographic imaging, whilst treatment is symptomatic not curative. Extracellular vesicles are nanoparticles that are involved in intercellular communication. The objective of this study was to investigate the feasibility of Raman and Optical Photothermal Infrared Spectroscopies to detect osteoarthritis using plasma-derived extracellular vesicles, specifically differentiating extracellular vesicles in diseased and healthy controls within the parameters of the techniques used. Plasma samples were derived from thoroughbred racehorses. A total of 14 samples were selected (control; n = 6 and diseased; n = 8). Extracellular vesicles were isolated using differential ultracentrifugation and characterised using nanoparticle tracking analysis, transmission electron microscopy, and human tetraspanin chips. Samples were then analysed using combined Raman and Optical Photothermal Infrared Spectroscopies. Infrared spectra were collected between 950-1800 cm^-1. Raman spectra had bands between the wavelengths of 900-1800 cm^-1 analysed. Spectral data for both Raman and Optical Photothermal Infrared Spectroscopy were used to generate clustering via principal components analysis and classification models were generated using partial least squared discriminant analysis in order to characterize the techniques' ability to distinguish diseased samples. Optical Photothermal Infrared Spectroscopy could differentiate osteoarthritic extracellular vesicles from healthy with good classification (93.4% correct classification rate) whereas Raman displayed poor classification (correct classification rate = -64.3%). Inspection of the infrared spectra indicated that plasma-derived extracellular vesicles from osteoarthritic horses contained increased signal for proteins, lipids and nucleic acids. For the first time we demonstrated the ability to use optical photothermal infrared spectroscopy combined with Raman spectroscopy to interrogate extracellular vesicles and osteoarthritis-related samples. Optical Photothermal Infrared Spectroscopy was superior to Raman in this study, and could distinguish osteoarthritis samples, suggestive of its potential use diagnostically to identify osteoarthritis in equine patients. This study demonstrates the potential of Raman and Optical Photothermal Infrared Spectroscopy to be used as a future diagnostic tool in clinical practice, with the capacity to detect changes in extracellular vesicles from clinically derived samples.

Enflicoxib for canine osteoarthritis: A randomized, blind, multicentre, non-inferiority clinical trial compared to mavacoxib

BACKGROUND

This prospective, multisite, blinded, randomized, non-inferiority clinical study aimed to confirm the efficacy and safety of enflicoxib in the treatment of pain and inflammation associated with canine osteoarthritis. A total of 180 dogs were randomized to receive enflicoxib (n = 78), mavacoxib (n = 80) or placebo (n = 22). Dogs underwent veterinary assessments from day 0 to day 42 using a clinical sum score (CSS). Efficacy was also assessed by the owners using the Canine Brief Pain Inventory (CBPI). The primary efficacy endpoint was the overall CSS from day 0 to day 42.

RESULTS

The overall CSS expressed as area under the curve demonstrated non-inferiority of enflicoxib compared to mavacoxib, and both showed superiority over placebo. At the end of the study, average CSS, and the percentage of CSS responders for enflicoxib (3.64 and 74%) and mavacoxib (4.49 and 68%), was superior to placebo (7.15 and 29%). A faster onset of action was observed for enflicoxib as superiority over placebo was evidenced from the first efficacy assessment (day 7) onwards for both parameters, whereas mavacoxib was only significantly different from day 14 onwards. According to the owner assessment, the percentage of CBPI responders was 90%, 79%, and 43% for dogs treated with enflicoxib, mavacoxib and placebo, respectively, and superiority over placebo was demonstrated for both active treatments. In all secondary parameters, non-inferiority of enflicoxib versus mavacoxib was confirmed. The dog's quality of life improved in all groups, but only enflicoxib showed superiority versus placebo. When assessing severely affected dogs only, results were similar, thus confirming the efficacy of enflicoxib in all stages of canine OA. There were no differences between groups in the frequency of adverse events, which were most frequently mild affecting the gastrointestinal tract and recovered without treatment.

CONCLUSIONS

Enflicoxib is efficacious and safe for the treatment of pain and inflammation in any stage of canine osteoarthritis with a faster onset of action compared to mavacoxib.

External Radiation Dose to Owners of Canines Treated with ( 117m Sn) Radiosynoviorthesis for Osteoarthritis

ABSTRACT

A novel device in the veterinary market uses a colloid containing radioactive 117m Sn to treat osteoarthritis in the synovial joints of canines. The technique of injecting a radioisotope to restore synovia is referred to as radiosynoviorthesis. The outpatient canine procedure uses a maximum administration of 222 MBq of 117m Sn injected into one or more joints. Due to the 13.91 d half-life and 158.6 keV gamma output of 117m Sn, abiding by the annual public dose limit of 1 mSv is of primary regulatory concern. The therapy protocol starts with a pre-screening questionnaire to establish owner and animal behavior patterns. The questionnaire is used to determine the duration of written time and distance limitations post therapy. In this study, external radiation doses to owners were measured by providing optically stimulated luminescent dosimeters (OSLD) for up to 30 d post-treatment of the pet. Twelve owners were measured over various time frames at two licensed locations independent of each other. In one location, the average (OSLD) measured 0.029 mSv over a 14-d wear period. In the second location, the average (OSLD) measured 0.057 mSv over a 30-d wear period; both values were well below the recommended annual public dose. The overall average extrapolated external radiation dose was estimated at 0.092 mSv, while the maximum dose estimate was 0.25 mSv. The (OSLD) results and extrapolated owner doses provide reasonable assurance that the public dose limits will be met.

Evaluation of clinical efficacy of undenatured type II collagen supplementation compared to cimicoxib and their association in dogs affected by natural occurring osteoarthritis

The aim of the study was to evaluate the clinical efficacy of 30 days treatment of undenatured type II collagen(UC-II®), compared to cimicoxib and to their combination, in osteoarthritic dogs. Client-owned dogs were enrolled in a clinical, randomized, controlled and prospective study. Posture, lameness, pain, range of motion and x-ray of affected joint(s) were evaluated and scored based on severity (CLINICAL score). The Liverpool Osteoarthritis in Dogs survey was used to score the owner evaluation of dog's mobility (LOAD score and MOBILITY score). Osteoarthritis (OA) stage was defined through the Canine Osteoarthritis Staging tool (COAST). After diagnosis (T0), all patients were randomly assigned to different treatment groups: C group = cimicoxib 2 mg/kg/day orally OS, F group = UC-II® 1 tablet per day OS; C + F group = cimicoxib-UC-II® at the same previous dosages; CTR group = dogs who didn't received any treatment. All treatments were administered for 30 days. Seventy-six dogs completed the study. LOAD score was recorded significant lower after treatment for each group, with a reduction in percentage of 29.5% for C, 31.4% for F, 21.1% for C + F. LOAD score was lower in C(P = 0.04), F(P = 0.001) and C + F(P = 0.009) group at T30 than CTR group. MOBILITY and CLINICAL scores were significantly lower in all groups at T30, when compared to T0. MOBILITY score was lower than CTR in C(P = 0.02) and F(P = 0.01); CLINICAL score was lower in C + F(P = 0.016). The present findings prove that the treatment with UC-II®, cimicoxib and their combination provide significant reduction in clinical signs associated with OA.

Multiple session mesotherapy for management of coxofemoral osteoarthritis pain in 10 working dogs: A case series

The aim of this study was to document the effects of mesotherapy in working dogs diagnosed with hip osteoarthritis (OA) and related pain. Ten police working dogs with hip OA and related pain were treated with a combination of lidocaine, piroxicam, and thiocolchicoside, injected in multiple intradermal points. Seven treatment sessions were conducted. The Canine Brief Pain Inventory (CBPI) and the Hudson Visual Analogue Scale (HVAS) were used in the assessment of response to treatment compared to evaluation before treatment (T0), after 15 d, 30 d, 60 d, 90 d, 120 d, 150 d, and 180 d after initial treatment. Results were compared using the Wilcoxon signed-rank test. Significant differences were experienced in CBPI scores comparing moments with T0: at 15 d (P = 0.03 for Pain Interference Score - PIS) and P = 0.02 for Pain Severity Score - PSS), 30 d (P < 0.05 for PIS and P < 0.05 for PSS), 60 d (P = 0.04 for PIS and P = 0.01 for PSS) and 180 d (P = 0.04 for PSS). Individual treatment results were considered successful in 40% of animals at 15 d and 30 d, 66.7% at 60 d, 44% at 90 d, 37.5% at 120 d, and 25% at 150 d. The HVAS scores showed no significant differences. Mesotherapy may be an option for the treatment of canine musculoskeletal-related pain. Further studies are required.

Observational study of the clinical value of the Canine Osteoarthritis Staging Tool

The aim of this multi-centred, cohort, prospective, observational study was to evaluate the clinical application of the canine osteoarthritis staging tool (COAST), in dogs affected by osteoarthritis (OA). In all dogs, a COAST stage was obtained based on the Liverpool Osteoarthritis in Dogs (LOAD) score and a complete orthopaedic and radiographic examination. The severity of OA (COAST stage) was scored as 1 (preclinical), 2 (mild), 3 (moderate), and 4 (severe). These scores were compared with the overall subjective opinion of experienced orthopedic surgeons who examined the dogs (Clinical Opinion). Data were analysed with descriptive statistic, multiple regression analysis, chi-square and Bland-Altman tests (P < 0.05). In total, 362 evaluations were performed in 202 dogs. Clinical Opinion had a greater proportion of stage 1 and 2 cases compared to COAST (P < 0.0001). The proportion of stage 4 cases was higher in COAST compared to Clinical Opinion (P < 0.0001). The proportions of Stage 3 cases were similar in the two evaluation systems. COAST had a strong correlation (r = 0.79; P < 0.01) with Clinical Opinion. Overall, the two evaluation systems exhibited strong agreement (mean bias 0.51). Stages 1 and 2 had weaker agreement (mean bias 1.04 and 0.75, respectively), than stage 3 and stage 4 (mean bias 0.46 and 0.0, respectively).

A pilot study examining a proprietary herbal blend for the treatment of canine osteoarthritis pain

Osteoarthritis is the most common joint disease in dogs. Despite the use of nonsteroidal anti-inflammatory drugs (NSAIDs), many owners seek natural therapies; either to augment the response to NSAIDs, or as a replacement. Substantial research has been directed to investigation of novel therapies. A randomized, double-blinded, controlled study was conducted to assess the efficacy of a herbal remedy for treatment of canine osteoarthritis pain. Client-owned dogs (N = 24) with osteoarthritis were enrolled between 2 veterinary hospitals. Each dog underwent veterinary and owner assessment at 0, 4, and 8 weeks, using the Canine Brief Pain Inventory and Hudson activity scale. Blood was collected for a complete blood (cell) count (CBC) and serum chemistry analysis. The product was deemed to be safe and well-tolerated at the manufacturer recommended dosage, with no significant changes seen in the CBC or serum biochemical analyses. Aside from1 dog that developed gastrointestinal upset, all other dogs tolerated the supplement without complication. The supplement did not statistically improve clinical signs in dogs based on veterinary or owner assessments of lameness. There was a treatment/time effect when assessing veterinary pain scores; however, post-hoc analysis suggests no observable benefit of treatment compared with the placebo group at any time point.

Effect of crude fiber and total dietary fiber on the calculated nitrogen-free extract and metabolizable energy content of various dog foods fed to client-owned dogs with osteoarthritis

OBJECTIVE

To compare measurements of crude fiber (CF) and total dietary fiber (TDF) for various dog foods and their effect on the calculated nitrogen-free extract and metabolizable energy (ME) content, and to compare label-guaranteed and laboratory-analyzed macronutrient values.

SAMPLES

51 dog foods fed to client-owned dogs with osteoarthritis.

PROCEDURES

Foods were analyzed for dry matter, ash, crude protein, acid-hydrolyzed fat, CF, and TDF. Metabolizable energy was calculated by use of a formula with modified Atwater factors and formulas recommended by the National Research Council that included both CF and TDF values. Linear regression analysis was performed to determine the correlation between CF and TDF values.

RESULTS

Only a few foods failed to conform to the guaranteed analysis for all macronutrients except for CF, in which approximately 40% of the foods exceeded the guaranteed maximum values. The CF and TDF values were moderately correlated (r = 0.843). Correlations among CF- and TDF-based ME estimations were moderate with use of the modified Atwater formula and strong with use of the National Research Council formulas (r = 0.86 and r = 0.91, respectively).

CONCLUSIONS AND CLINICAL RELEVANCE

Values for CF were the most variable of the macronutrients of the evaluated dog foods and results suggested that CF is an incomplete and inaccurate measurement of dietary fiber content and, thus, its inaccuracy may lead to inaccurate and variable ME values.

Effect of intravenous tiludronate disodium administration on the radiographic progression of osteoarthritis of the fetlock joint in Standardbred racehorses

OBJECTIVE

To compare the effects of tiludronate disodium and 3 other medical treatments on clinical and radiographic findings and biomarkers of disease progression in horses with osteoarthritis of the fetlock joint.

ANIMALS

100 Standardbred racehorses with spontaneous traumatic injury of the fetlock joint.

PROCEDURES

Horses were retrospectively grouped by whether they received tiludronate IV or triamcinolone acetonide and hyaluronan, polysulfated glycosaminoglycan, or interleukin-1 receptor antagonist protein intra-articularly. Data were collected on clinical, radiographic, and ultrasonographic findings and results for serum and synovial samples obtained before and 6 months after treatment. Lameness score, joint flexion test response, radiographic score, serum concentrations of tumor necrosis factor-α and carboxy-terminal telopeptides of collagen types I and II (CTX-I and II, respectively), and synovial fluid concentrations of interleukin-1β, prostaglandin E₂, and CTX-II were compared among treatments.

RESULTS

All treatments resulted in a significant improvement in lameness score and joint flexion test response at 6 months. In horses that received triamcinolone acetonide and hyaluronan, synovial fluid interleukin-1β, prostaglandin E₂, and CTX-II concentrations decreased after treatment, suggesting this treatment inhibited progression of hyaline cartilage degeneration and inflammatory processes. Horses that received tiludronate were the only group that had a decrease in radiographic score and serum CTX-I concentration after treatment, supporting the effect of tiludronate on bone metabolism. Tiludronate treatment was also followed by increases in serum and synovial fluid concentrations of CTX-II, a marker of cartilage damage.

CONCLUSIONS AND CLINICAL RELEVANCE

Tiludronate appeared to inhibit the radiographic progression of osteoarthritis in high-motion joints of racehorses at 6 months after treatment by inhibiting subchondral bone remodeling. Whether this effect was associated with a worsening of progressive cartilage damage remains to be ascertained.

Anisotropy of the Radiation Field Following Canine Sn-117m Treatment

ABSTRACT

Tin-117m (117mSn) is used to treated dogs with osteoarthritic joints by radiosynoviorthesis. The internal conversion and Auger electrons emitted by the 117mSn provide the therapeutic effect. Sn-117m also emits gamma rays, of which the most significant is 158.6 keV. The external radiation field around a treated dog is of interest to limit the dose to the owners/caretakers of the dog. The dog's torso attenuates the radiation being emitted toward the opposite side of the dog's body. This leads to a radiation field that is significantly non-isotropic. This study characterizes the anisotropy of this field to permit maximum dose rate measurements to be used to calculate the dose to individuals in the vicinity of the dog. Measurements were made in nine directions and at two distances, 0.3 and 1.0 m, to characterize common distances and spatial orientations for human-dog interactions. From these measurements, the percent reduction in the average dose rate compared to the maximum dose rate was determined. From a radiation safety perspective, the important factor is the minimum amount of shielding effectiveness or percent reduction that can be expected. A reasonable measure for this value is the fifth percentile of the shielding effectiveness distribution. The fifth percentile shielding effectiveness measures are 27% and 21% at 0.3 and 1.0 m, respectively.

Medial malleolus fragmentation following talocalcaneal arthrodesis by a dorsomedial approach in a horse

A 16-year-old, Quarter Horse mare was presented for a 3/5 right hind lameness associated with osteoarthritis of the talocalcaneal joint (TCLJ). Positron emission tomography (PET) and computed tomography (CT) demonstrated marked increased uptake of 18F-sodium fluoride and bone remodeling at the medial facet of the TCLJ, respectively. Under general anesthesia 2 cortical screws (4.5 and 5.5 mm) were placed in neutral fashion via an arthrotomy from dorsomedial to plantaromedial through the medial facet of the TCLJ followed by copious lavage of the tarsocrural joint. Eight weeks after surgery, observable effusion of the tarsocrural joint was present and lameness had worsened. Radiographic examination revealed a fragmented medial malleolus of the tibia, likely secondary to repetitive trauma of the screw heads during tarsal flexion. Repeated CT showed partial fusion of the TCLJ. Both screws were removed and the tarsocrural joint was thoroughly lavaged arthroscopically. At a 20-month recheck the lameness had not improved, and ultrasound examination revealed severe thickening of the TCLJ capsule. Recheck examination 48 mo after surgery showed complete fusion of the TCLJ and resolution of the lameness. Key clinical message: Diagnosis of osteoarthritis of the TCLJ is challenging. Management by arthrodesis using a dorsomedial approach can result in fragmentation of the medial malleolus, with secondary synovitis and capsulitis of the tarsocrural joint.