Mechanical osteoarthritis of the hip in a one medicine concept: a narrative review.

Human and veterinary medicine have historically presented many medical areas of potential synergy and convergence. Mechanical osteoarthritis (MOA) is characterized by a gradual complex imbalance between cartilage production, loss, and derangement. Any joint instability that results in an abnormal overload of the joint surface can trigger MOA. As MOA has a prevailing mechanical aetiology, treatment effectiveness can only be accomplished if altered joint mechanics and mechanosensitive pathways are normalized and restored. Otherwise, the inflammatory cascade of osteoarthritis will be initiated, and the changes may become irreversible. The management of the disease using non-steroidal anti-inflammatory drugs, analgesics, physical therapy, diet changes, or nutraceuticals is conservative and less effective. MOA is a determinant factor for the development of hip dysplasia in both humans and dogs. Hip dysplasia is a hereditary disease with a high incidence and, therefore, of great clinical importance due to the associated discomfort and significant functional limitations. Furthermore, on account of analogous human and canine hip dysplasia disease and under the One Medicine concept, unifying veterinary and human research could improve the well-being and health of both species, increasing the acknowledgement of shared diseases. Great success has been accomplished in humans regarding preventive conservative management of hip dysplasia and following One Medicine concept, similar measures would benefit dogs. Moreover, animal models have long been used to better understand the different diseases' mechanisms. Current research in animal models was addressed and the role of rabbit models in pathophysiologic studies and of the dog as a spontaneous animal model were highlighted, denoting the inexistence of rabbit functional models to investigate therapeutic approaches in hip MOA.

Evaluation of the thermographic response of the lumbar region in dogs with bilateral hip osteoarthritis.

Infrared thermography is suggested as a method of medical assistance for evaluating anatomical regions where there may be some inflammatory or painful condition that requires immediate medical attention. For this reason, this study aimed to characterize digital thermography of the lumbar region in police working dogs with hip osteoarthritis, 47 dogs with bilateral hip osteoarthritis were evaluated. A thermographic dorsoventral view of the dogs' backs were obtained, and mean and maximum temperatures were determined. In addition, results from the Canine Brief Pain Inventory, Liverpool Osteoarthritis in Dogs (LOAD), the Canine Orthopedic Index, and weight-bearing distribution evaluation were collected. Results were compared with an Independent Samples T-Test or ANOVA, followed by an LSD post hoc. Multiple regression was run to predict temperatures from age, sex, breed, body weight, and Orthopedic Foundation for Animals hip score and to predict clinical metrology scores and weight-bearing distribution results from temperature results. The sample included 28 males and 19 females, with a mean age of 6.3 ± 2.5 years and bodyweight of 26.9 ± 5.1 kg, with osteoarthritis hip scores of mild (70.2%), moderate (21.3%), and severe (8.5%). Significant differences were observed in mean temperatures between German Shepherd Dogs (GSD) and Labrador Retrievers (LR) (p < 0.01), and LR and Belgian Malinois (BM) (p=0.02). Mean temperature contributed to the prediction of LOAD and stiffness. LR showed significantly higher temperature values than GSD and BM. No differences were observed between osteoarthritis hip scores and mean temperature values contributed to LOAD scores' prediction. This relation needs to be addressed in further studies, involving a larger number of animals, and to determine changes in response to treatment.

Initial psychometric evaluation of the Portuguese version of the Liverpool Osteoarthritis in Dogs.

BACKGROUND: Osteoarthritis (OA) is the most commonly diagnosed joint disease in companion animals, and proper tools are necessary to assess patients and response to treatment. We aimed to perform an initial psychometric evaluation of the Portuguese version of the Liverpool Osteoarthritis in Dogs (LOAD).Fifty Police working dogs with bilateral hip OA were assessed in a prospective, randomized, double-blinded study. Canine handlers, who were native Portuguese speakers, completed a copy of the translated version of the LOAD. Their results were compared with those of fifty sound dogs. Construct validity was evaluated by assessing differences between OA and sound animals with the Mann-Whitney test. Further evaluation was performed with the Kaiser-Meyer-Olkin measure of sampling adequacy, Eigenvalue, and scree-plot analysis. Internal consistency was tested with Cronbach's α. RESULTS: A significant difference was observed between OA and sound dogs (p < 0.01), indicating construct validity. Two factors accounted for 81.5% of the total variance. Cronbach's α was 0.96, and a high inter-item correlation was observed, raging from 0.76 to 0.95, showing strong internal consistency. We presented criterion and construct validity of the Portuguese version of the LOAD, which is valid for use in the Portuguese language. It is an additional stage in providing a broader number of clinicians with an accessible tool to evaluate dogs with osteoarthritis. Further studies are required.

A first report on the efficacy of a single intra-articular administration of blood cell secretome, triamcinolone acetonide, and the combination of both in dogs with osteoarthritis.

BACKGROUND: Osteoarthritis represents a significant welfare problem for many dogs, with limited therapeutic options other than palliative pain control. To evaluate the effect of the intra-articular administration of blood cell secretome and triamcinolone, 15 dogs with bilateral hip osteoarthritis were randomly assigned to a blood cell secretome (BCSG, n = 5), triamcinolone (TG) or their combination group (BCS + TG, n = 5). BCSG received a single intra-articular administration of 3 ml of blood cell secretome, TG 0.5 ml of triamcinolone acetonide 40 mg/ml, and BCS + TG received the combined products. The volume to administrate was corrected to 3.5 ml with saline. On days 0, 8, 15, 30, 60, 90, 120, 150, and 180, a copy of the Canine Brief Pain Inventory (divided into pain interference score-PIS and Pain Severity Score-PSS), Liverpool Osteoarthritis in Dogs (LOAD), Hudson Visual Analogue Scale (HVAS), and Canine Orthopedic Index (COI, divided into function, gait, stiffness, and quality of life) was completed. Results were analyzed with the Kruskal-Wallis test and the Kaplan-Meier estimators were conducted and compared with the Log Rank test, p < 0.05. RESULTS: Animals in the sample had a mean age of 9.0 ± 2.9 years and a bodyweight of 28.8 ± 4.1 kg. Hips were classified as moderate (8) and severe (7) osteoarthritis. No differences were found between groups at T0 regarding considered evaluations. Significant differences were observed between groups in pain scores from + 8d- + 150d, with BCS + TG exhibiting better results. The same was observed for HVAS and LOAD, from + 8d- + 120d. Improvements were also observed in several dimensions of the COI. Kaplan-Meier estimators showed that BCS + TG produced longer periods with better results, followed by BCSG and TG. CONCLUSION: The intra-articular administration of blood cell secretome improved the clinical signs and scores of several clinical metrology instruments in dogs with hip OA, particularly when combined with triamcinolone. Further studies are required.

Pericapsular hip desensitization in dogs: a cadaveric study and case series.

OBJECTIVE: To develop and assess the efficacy of an ultrasound (US)-guided pericapsular hip desensitization (PHD) technique in dogs. STUDY DESIGN: Prospective, randomized, anatomical study and a case series. ANIMALS: A total of 30 healthy dogs, eight canine cadavers and seven dogs with hip osteoarthritis. METHODS: After studying the US anatomy of the medial aspect of the coxofemoral joint and determining an acoustic window to perform an US-guided PHD in healthy dogs, the US-guided PHD was performed bilaterally in canine cadavers. A low [(LV) 0.1 mL kg-1] and high [(HV) 0.2 mL kg-1] volume of dye was injected per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection, and comparison between LV and HV was assessed using Fisher's exact test. Then, the US-guided PHD was performed using a triamcinolone-bupivacaine solution in dogs with hip osteoarthritis. Dynamic pain response was assessed before and after injection. The canine brief pain inventory (CBPI) questionnaire was used to assess treatment efficacy and duration. RESULTS: The US-guided PHD could be performed by inserting the needle between the iliopsoas muscle and the periosteum of the ilium. The articular branches of the femoral and obturator nerves were stained in all cadavers using both volumes. The main femoral nerve was never stained, but the main obturator nerve was stained in 37.5% and 100% of injections using LV and HV, respectively (p = 0.026). Treated animals showed decreased dynamic pain response after the injection. Compared with baseline, CBPI scores were reduced by ≥ 50% for ≥ 12 weeks in all but one dog. CONCLUSIONS AND CLINICAL SIGNIFICANCE: The US-guided PHD with both 0.1 and 0.2 mL kg-1 volumes stained the articular branches of the femoral and obturator nerves in canine cadavers and was associated with clinical improvement in dogs with hip osteoarthritis.

Platelet-rich plasma therapy in dogs with bilateral hip osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is the most commonly diagnosed joint disease in companion animals, and hip OA is commonly diagnosed in the canine population. The use of platelet-rich plasma has gained increasing interest for the treatment of musculoskeletal conditions in companion animals. To evaluate the effect of the intra-articular administration of platelet-rich plasma in police working dogs with bilateral hip OA compared to a control group, twenty dogs were assigned to a control group (CG, n = 10) or treatment group (PG, n = 10), using the statistical analysis software. PG received two intra-articular administrations of platelet-rich plasma, 14 days apart, while CG received an intra-articular administration of saline, in the same moments. Response to treatment was determined with the Canine Brief Pain Inventory, Liverpool Osteoarthritis in Dogs, Canine Orthopedic Index, and Hudson Visual Analogue Scale, before treatment, + 8, + 15, + 30, + 60, + 90, + 120, 150, and + 180 days after initial treatment. Kaplan-Meier estimators were conducted and compared with the log-rank test. Cox proportional hazard regression analysis was performed to determine treatment survival, p < 0.05. RESULTS: The sample comprised 20 animals of both sexes (male n = 12, female n = 8), with a mean age of 8.4 ± 2.4 years and a bodyweight of 31.5 ± 5.7 kg. Joints were classified as moderate (13) and severe (7) according to the Orthopedic Foundation for Animals grading scheme. No differences were found between groups at the initial evaluation. Better results with the majority of scores were observed in the PG, in some cases lasting up to the last evaluation moment. Kaplan-Meier estimators showed that PG produced longer periods with better results in all scores compared to CG. Treatment was the covariate influencing all scores in the Cox regression analysis. OFA hip score also influenced two dimensions of the Canine Orthopedic Index. CONCLUSION: The intra-articular administration of platelet-rich plasma can improve pain and functional scores of police working dogs with bilateral hip OA, compared with a control group. Its effects lasted for significantly longer periods, and treatment was the main covariate affecting the improvements observed.

Evaluation of digital thermography imaging to assess and monitor treatment of police working dogs with naturally occurring hip osteoarthritis.

BACKGROUND: In dogs, thermal imaging has been documented only recently, but a growing interest in this modality has led to studies using thermography to assess pathologies in the canine hip, stifle, elbow, intervertebral disc, and bone neoplasia. This study aimed to evaluate the use of digital thermography in assessing and evaluating treatment response in dogs with hip osteoarthritis (OA) and comparing its results with an objective measure and two clinical metrology instruments. In an experimental, randomized, double-blinded study, one hundred hip joints of fifty police working dogs with bilateral hip OA were evaluated. A dorsoventral and lateral thermographic image were obtained on days 0, 8, 15, 30, 90, and 180. Mean and maximal temperatures were determined. Additionally, the animal's weight-bearing distribution and radiographic examination of the hip joint (extended legs ventrodorsal view) were performed. Copies of the Canine Brief Pain Inventory (CBPI) and Canine Orthopaedic Index (COI) were obtained. Results were analyzed by ANOVA, followed by an LSD post-hoc test, and correlations were assessed with Spearman correlation coefficient, with p < 0.05. RESULTS: Values recorded on the lateral view were higher than those on the dorsoventral view. No differences or correlations were found between Orthopedic Foundation for Animals hip grades and temperature. Digital thermographic images showed a weak significant correlation with weight-bearing evaluations (r = 0.13, p < 0.01) and different clinical metrology instruments scores (r = - 0.25, p < 0.01 for pain severity score, and r = - 0.21, p = 0.04 for gait). It also correlated with radiographic findings, specifically the circumferential femoral head osteophyte and caudolateral curvilinear osteophyte. CONCLUSION: To our knowledge, this is the first study presenting the digital thermography assessment of Police working dogs submitted to treatment for hip OA. Digital thermography, mainly based on a lateral view evaluation, showed a weak significant correlation with stance analysis and clinical metrology instruments scores.

Clinical and diagnostic imaging findings in police working dogs referred for hip osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is the most commonly diagnosed joint disease in veterinary medicine, with at least 80% of the cases of lameness and joint diseases in companion animals being classified as OA. Sporting and working animals are more predisposed to develop OA since they are exposed to chronic fatigue injuries, leading to bone and muscular tissue damage and failure, resulting in clinical signs. To characterize the clinical signs and diagnostic findings of Police working dogs presenting with bilateral hip OA at the time of diagnosis. Fifty animals were evaluated with a bodyweight ≥ 15 kg, be older than two years, and without any medication or nutritional supplements for ≥ 6 weeks. RESULTS: Weight distribution, joint range of motion at flexion and extension, thigh girth, digital thermography, and radiographic signs were collected. Data from different Clinical Metrology Instruments (CMI) were collected: Canine Brief Pain Inventory, Liverpool Osteoarthritis in Dogs, Canine Orthopedic Index, and the Hudson Visual Analogue Scale. Results were compared by breed, age, sex, and Orthopaedic Foundation for Animals hip grades with the Independent Samples T-Test, ANOVA followed by a Bonferroni post hoc test, and Pearson correlation coefficient, with p < 0.05. The sample included 30 males and 20 females, with a mean age of 6.5 ± 2.4 years and a bodyweight of 26.7 ± 5.2 kg. Animals with weight distribution below normal levels had significant variations of joint extension and function scores. This evaluation was the only not correlated with at least one breed. Animals with caudolateral curvilinear osteophyte showed a poorer clinical presentation and worse scores in all considered CMIs. Radiographic changes correlated with age and corresponded to worse CMIs scores and weight distribution. Dutch Shepherd Dogs showed better CMI scores than the other considered breeds. CONCLUSIONS: Police working dogs presented with complaints related to hip OA at an early stage of the disease. Hip scores influenced clinical presentation, with moderate cases showing lower thigh girth and worse pain interference and severity, and function scores than mild cases. Patients with severe OA had lower thermographic evaluations than patients with moderate OA. Age was the primary variable influencing considered CMI scores.

Hip osteoarthritis in dogs: a randomized study using mesenchymal stem cells from adipose tissue and plasma rich in growth factors.

PURPOSE: The aim of this study was to compare the efficacy and safety of a single intra-articular injection of adipose mesenchymal stem cells (aMSCs) versus plasma rich in growth factors (PRGF) as a treatment for reducing symptoms in dogs with hip osteoarthritis (OA). METHODS: This was a randomized, multicenter, blinded, parallel group. Thirty-nine dogs with symptomatic hip OA were assigned to one of the two groups, to receive aMSCs or PRGF. The primary outcome measures were pain and function subscales, including radiologic assessment, functional limitation and joint mobility. The secondary outcome measures were owners' satisfaction questionnaire, rescue analgesic requirement and overall safety. Data was collected at baseline, then, 1, 3 and 6 months post-treatment. RESULTS: OA degree did not vary within groups. Functional limitation, range of motion (ROM), owner's and veterinary investigator visual analogue scale (VAS), and patient's quality of life improved from the first month up to six months. The aMSCs group obtained better results at 6 months. There were no adverse effects during the study. Our findings show that aMSCs and PRGF are safe and effective in the functional analysis at 1, 3 and 6 months; provide a significant improvement, reducing dog's pain, and improving physical function. With respect to basal levels for every parameter in patients with hip OA, aMSCs showed better results at 6 months.

Autologous point-of-care stromal vascular fraction transplantation in dogs with advanced osteoarthritis of the knee and hip joints.

OBJECTIVE: The aim of the study was to assess lameness in dogs with advanced osteoarthritis of the hip and knee joints after a single autologous point-of-care transplantation of the Stromal Vascular Fraction (SVF) into the affected joint. MATERIALS AND METHODS: During a minilaparotomy, 10 g of falciform fat was removed from each patient for each joint to be treated. A modern and time-saving procedure (ARC TM System, InGeneron GmbH, Houston, USA) was used for the in-house preparation of the SVF, so that the isolated cells could be applied to the respective joint within 2 h after fat removal. In total, five knee joints of five patients and seven hip joints of four patients were treated. RESULTS: Improvement in lameness according to owner questionnaires was seen in 3 of 5 patients with knee joint arthritis and 2 of 4 patients with hip joint arthritis. Based on gait analysis, only one dog with gonarthrosis and one dog with coxarthrosis showed improvement up to a maximum of 3 months after surgery. CONCLUSION: This is the first case series on the treatment of osteoarthrosis of the knee or hip joint using point-of-care transplantation of the SVF. In individual cases, this method may represent a therapeutic approach for the treatment in dogs with advanced cox- or gonarthrosis, although only a short-term effect can be expected, which calls into question the effort and costs involved.

Does a placebo effect really occur in dogs afflicted by hip osteoarthritis as measured by force platform gait analysis?

A recent study investigated the therapeutic response of dogs afflicted by hip osteoarthritis when evaluating therapeutic modalities compared to a negative (placebo) control group. Authors suggested a placebo effect based on peak vertical force measurement. In addition, small effect size for each of the tested therapeutics as well as the extremely large sample size needed (>450) to discern therapeutic efficacy using force platform gait analysis were reported. We wish to express our concerns regarding the eligibility criteria used to select the studied cohort, the small effect size, and the placebo effect reported in force platform gait analysis.

Minimal clinically-important differences for the "Liverpool Osteoarthritis in Dogs" (LOAD) and the "Canine Orthopedic Index" (COI) in dogs with osteoarthritis.

OBJECTIVE: Osteoarthritis is the most common joint disease in companion animals. Several client-report outcome measures (CROMs) have been developed and validated to monitor patients and their response to treatment. However, estimates for minimal clinically-important differences for these CROMs in the context of osteoarthritis have not been published. PATIENTS AND METHODS: Data from the Clínica Veterinária de Cães (Portuguese Gendarmerie Canine Clinic) clinical records were extracted. Baseline and 30-day post-treatment follow-up data from 296 dogs treated for hip osteoarthritis were categorized based on an anchor question, and estimates of minimal clinically-important differences (MCIDs) using distribution-based and anchor-based methods were performed. RESULTS: For the LOAD, the anchor-based methods provided a MCID estimate range of -2.5 to -9.1 and the distribution-based methods from 1.6 to 4.2. For the COI, the anchor-based methods provided a MCID estimate range of -4.5 to -16.6 and the distribution-based methods from 2.3 to 2.4. For the dimensions of COI, values varied from -0.5 to -4.9 with the anchor-based methods and from 0.6 to 2.7 with the distribution-based methods. Receiver operator characteristic curves provided areas under the curve >0.7 for the COI, indicating an acceptable cut-off point, and >0.8 for the LOAD, indicating an excellent cut-off point. CONCLUSION: Our estimates of MCIDs for dogs with OA were consistent with previously proposed values of -4 for the LOAD and -14 for the COI in a post-surgical intervention context. ROC curve data suggest that LOAD may more reliably differentiate between anchor groups. We also presented estimates from COI of -4 for Stiffness, Function, and Gait and -3 for quality of life. These estimates can be used for research and patient monitoring.

Initial Psychometric Evaluation of the Portuguese Version of the Canine Orthopedic Index.

OBJECTIVE: The aim of this study was to perform the initial psychometric evaluation of the Portuguese version of the Canine Orthopaedic Index (COI). STUDY DESIGN: In a prospective, randomized study, a group of 50 police working dogs with bilateral hip osteoarthritis was assessed. A copy of the translated Portuguese version of the COI was completed by canine handlers, native Portuguese speakers. This result was compared with that of 50 sound dogs. Construct validity was determined by comparing sound dogs and dogs with osteoarthritis scores with the Mann-Whitney test. Additionally, the Kaiser-Meyer-Olin measure of sampling adequacy, eigenvalue, and scree-plot analysis were performed. Internal consistency was tested with Cronbach's α. RESULTS: A significant difference was observed between osteoarthritis and sound dogs in all dimensions of the COI (p < 0.01 for all), indicating construct validity. Two factors accounted for 87.8% of the total variance. Cronbach's α was 0.98, with a high interitem correlation, accounting for strong internal consistency. CONCLUSION: We presented criterion and construct validity of the Portuguese version of the COI. It is a step in providing clinicians with a validated and accessible tool to evaluate orthopaedic patients. Further studies are required.

Effect of analgesic therapy on clinical outcome measures in a randomized controlled trial using client-owned dogs with hip osteoarthritis.

BACKGROUND: Pain and impaired mobility because of osteoarthritis (OA) is common in dogs and humans. Efficacy studies of analgesic drug treatment of dogs with naturally occurring OA may be challenging, as a caregiver placebo effect is typically evident. However, little is known about effect sizes of common outcome-measures in canine clinical trials evaluating treatment of OA pain. Forty-nine client-owned dogs with hip OA were enrolled in a randomized, double-blinded placebo-controlled prospective trial. After a 1 week baseline period, dogs were randomly assigned to a treatment (ABT-116 - transient receptor potential vanilloid 1 (TRPV1) antagonist, Carprofen - non-steroidal anti-inflammatory drug (NSAID), Tramadol - synthetic opiate, or Placebo) for 2 weeks. Outcome-measures included physical examination parameters, owner questionnaire, activity monitoring, gait analysis, and use of rescue medication. RESULTS: Acute hyperthermia developed after ABT-116 treatment (P < 0.001). Treatment with carprofen (P ≤ 0.01) and tramadol (P ≤ 0.001) led to improved mobility assessed by owner questionnaire. Nighttime activity was increased after ABT-116 treatment (P = 0.01). Kinetic gait analysis did not reveal significant treatment effects. Use of rescue treatment decreased with treatment in the ABT-116 and Carprofen groups (P < 0.001). Questionnaire score and activity count at the end of treatment were correlated with age, clinical severity at trial entry, and outcome measure baseline status (SR ≥ ±0.40, P ≤ 0.005). Placebo treatment effects were evident with all variables studied. CONCLUSION: Treatment of hip OA in client-owned dogs is associated with a placebo effect for all variables that are commonly used for efficacy studies of analgesic drugs. This likely reflects caregiver bias or the phenomenon of regression to the mean. In the present study, outcome measures with significant effects also varied between groups, highlighting the value of using multiple outcome measures, as well as an a priori analysis of effect size associated with each measure. Effect size data from the present study could be used to inform design of future trials studying analgesic treatment of canine OA. Our results suggest that analgesic treatment with ABT-116 is not as effective as carprofen or tramadol for treatment of hip arthritis pain in client-owned dogs.

Canine hip dysplasia: reviewing the evidence for nonsurgical management.

OBJECTIVE: To systematically review the evidence available for nonsurgical management of hip dysplasia (HD). STUDY DESIGN: Literature review. METHODS: Databases (Pubmed, Veterinary Information Network) were searched for clinical studies on nonsurgical management of HD in dogs. The evidence in each study was reviewed and assigned a score (I-IV) based on previously reported levels of evidence. RESULTS: Fourteen articles were identified that met the inclusion criteria, including 3 Level IV, 4 Level III, and 7 Level II studies. Methods of nonsurgical management reviewed included: activity restrictions, weight management, acupuncture, modulation of joint disease by polysulfated glycosaminoglycans, mesenchymal stem cell therapy, and extra corporeal shock wave therapy. CONCLUSION: Weight management is an effective and important component of managing dogs with HD and associated osteoarthritis. Techniques that modulate the progression of joint disease may also be beneficial for treating dogs with HD. Further studies are needed to investigate other methods of managing HD such as hydrotherapy and physical rehabilitation.

Chronology of hip dysplasia development in a cohort of 48 Labrador retrievers followed for life.

OBJECTIVE: To determine the chronology of radiographic signs of canine hip dysplasia (CHD), specifically joint laxity and secondary osteoarthritis (OA). STUDY DESIGN: Longitudinal cohort study. ANIMALS: Paired littermates, 48 Labrador retrievers. METHODS: Conventional, ventrodorsal, hip-extended (HE) radiographs were evaluated yearly for CHD according to the subjective criteria of the Orthopedic Foundation for Animals (OFA). PennHIP screening was performed at 2 years of age to assess joint laxity by distraction index (DI). Histopathologic evaluation of coxofemoral joints was performed at the dogs' natural end of life. RESULTS: Coxofemoral subluxation, as identified on the HE radiograph occurred by 2 years of age and not thereafter. Accuracy of OFA-criteria scoring was poor: 55% of dogs scored "normal" at 2 years of age became radiographically dysplastic by the end of life (45% negative predictive value, NPV); 92% of the dogs scored as normal at 2 years of age had histopathologic OA of CHD (8% NPV). The DI predicted all 48 dogs to be susceptible to OA of CHD and 98% had radiographic or histopathologic OA by the end of life. CONCLUSION: OFA-criteria score was profoundly influenced by environmental factors, such as diet restriction and age, reducing its value as a selection criterion. DI measurements were not influenced by dietary treatment suggesting higher trait heritability.

Pelvic limb kinematics and surface electromyography of the vastus lateralis, biceps femoris, and gluteus medius muscle in dogs with hip osteoarthritis.

OBJECTIVE: To measure the activity patterns of the vastus lateralis (VL), biceps femoris, and gluteus medius (GM) muscle at a walk in sound dogs and dogs with hip osteoarthritis (OA). ANIMALS: Dogs (n = 10) with hip OA and 7 clinically sound dogs. METHODS: Self-reflective markers and a high-speed camera system were used for kinematic measurements and surface electrodes were used for the electromyography (EMG). All measurements were performed on walking dogs. Maximal, minimal, and mean values of the joint angles were evaluated, together with the surface EMG data. RESULTS: In all muscles investigated, mean activity was significantly decreased during the early swing phase in dogs with hip OA. The VL and GM muscle of the clinically worse pelvic limb had significantly higher activity than the contralateral pelvic limb during early stance. CONCLUSION: The muscles investigated were significantly affected by hip OA. This finding suggests that there is a more distinct resting phase of the muscles during swing and a higher activity during early stance.

Radiographic hip joint phenotype of the Pembroke Welsh Corgi.

OBJECTIVE: To investigate the radiographic hip joint phenotype of the Pembroke Welsh Corgi. STUDY DESIGN: Prospective and retrospective cross-sectional study. ANIMALS: Pembroke Welsh Corgis (n = 399). METHODS: Ventrodorsal, hip-extended radiographs were evaluated for subluxation, osteoarthritis (OA), caudolateral curvilinear osteophytes (CCO), and circumferential femoral head osteophytes (CFHO) of PennHIP evaluated Corgis. Joint laxity was measured by distraction index (DI). RESULTS: All Corgis had DI > 0.30 (mean, 0.66), 6.8% had OA, 18% had subluxation, 22.3% had CCO, and 74.4% had CFHO. Higher DI increased the odds for subluxation and canine hip dysplasia (CHD) but not for OA, CCO, or CFHO. The presence of CCO increased the odds for OA by 4.6 times (P = .002) and 2.2 times (P = .01) for hip dysplasia. All dogs with OA had CFHO. The presence of CFHO increased the odds for subluxation by 8.7 times (p < .001) and 8.9 times (P < .001) for hip dysplasia. Subluxation increased the odds for OA by 15.4 times (P < .001). CONCLUSION: Corgis had a low frequency of conventional OA despite having hip laxity that has been shown to correlate with hip OA and hip dysplasia in large-breed dogs. The relationship between CCO and OA was similar to published findings in nonchondrodystrophic large-breed dogs and the CFHO was significantly associated with subluxation. Both CCO and CFHO are associated with hip dysplasia in this small chondrodystrophic breed.

Complications and owner assessment of canine total hip replacement: a multicenter internet based survey.

OBJECTIVE: To assess the variables associated with the complications of total hip replacement (THR) and report owner-assessed outcomes, through surgeon-based registration of cases via an online database, informed owner consent, and prospective outcomes assessment using a client-administered clinical metrology instrument. STUDY DESIGN: Prospective case series ANIMALS: Dogs (n = 170) METHODS: Entries into the British Veterinary Orthopaedic Association-Canine Hip Registry (BVOA-CHR) between January 2010 and August 2011 were reviewed. Variables evaluated included dog age, body weight, breed, and indication for THR and prosthesis. Associations between each variable and the incidence of complications were assessed using logistic regression. Additionally, an on-line, owner-administered outcomes assessment questionnaire (modified from the Liverpool Osteoarthritis in Dogs (LOAD) questionnaire) was used to collect data from owners. RESULTS: One hundred and seventy cases met the inclusion criteria. Surgical indications included hip dysplasia and coxofemoral osteoarthritis (n = 150), Legg-Calves-Perthes disease (7), coxofemoral luxation (6), fracture (4), slipped capital physis (2), and femoral head and neck ostectomy revision (1). Surgical implants were from 4 systems. The incidence of surgeon-reported complication was 9.4%. No significant association was identified between weight, age, sex, breed, indication for THR, surgical technique and prosthesis, and the incidence of complications. In 82% of the cases, owners described their satisfaction with the outcome of THR as "very good" and a total of 20% complication rate was reported. There was a statistically significant improvement in owner-assessed questionnaire score before and after THR (P < .001). CONCLUSIONS: The BVOA-CHR offers a novel framework for the prospective studies on THR and on a national/international scale. Initial complication rates from the BVOA-CHR are similar to previous studies.

Characterization of Weight-bearing Compensation in Dogs With Bilateral Hip Osteoarthritis.

To describe the weight-bearing compensation in working dogs with bilateral hip osteoarthritis (OA), 50 police working dogs were evaluated with a weight distribution platform at the initial evaluation and after intra-articular treatment (a negative control - 0.9% sodium chloride (NaCl), a platelet concentrate, Hylan G-F 20, triamcinolone hexacetonide or stanozolol). Six evaluation sessions were performed, over a 180-day period. Results were compared by breed, age, sex, weight and Orthopedic Foundation for Animals hip grade scores with the Independent Samples T-Test, repeated samples Analysis of variance and Pearson correlation coefficient, P < .05. Animals had a mean age of 6.5 ± 2.4 years and a bodyweight of 26.7 ± 5.2kg. No significant differences were observed when comparing weight-bearing for different breeds, sex, hip grades or weight during the initial evaluation. Significant differences were observed in deviation (P < .01) and symmetry index (P < .01) between the control and treatment groups during the follow-up period. A weight shift from pelvic to thoracic limbs was observed, with a weak, although a significant, correlation between a pelvic limb and the opposing contralateral thoracic limb. Labrador Retrievers showed higher symmetry index and deviation from normal values during the follow-up period than German Shepherd Dogs and Dutch Shepherd Dogs. Male dogs also showed higher symmetry index and deviation compared with females. At this period, the symmetry index showed a weak, although significant, correlation with body weight. Weight-bearing of all limbs correlated with the remaining limbs, reflecting a more balanced weight distribution than the initial evaluation. The weight distribution platform can be used to evaluate patients, at the initial presentation and during the assessment of response to treatment.