Effect of weight reduction on clinical signs of lameness in dogs with hip osteoarthritis

Effects of denervation of the hip joint on results of clinical observations and instrumented gait analysis in dogs with sodium urate crystal-induced synovitis

OBJECTIVE To evaluate the effects of selective hip joint denervation on gait abnormalities and signs of hip joint pain in dogs. ANIMALS 6 healthy adult hound-type dogs. PROCEDURES Minimally invasive denervation was performed on the right hip joint of each dog. Two weeks later, sodium urate was injected into the right hip joint to induce synovitis. Dogs were evaluated clinically and by use of instrumented gait analysis before and 2 weeks after minimally invasive denervation and 4, 8, and 24 hours after induction of synovitis. Dogs were euthanized, and necropsy and histologic examination were performed. RESULTS No kinetic or kinematic gait modifications were detected 2 weeks after minimally invasive denervation. Denervation did not eliminate signs of pain and lameness associated with sodium urate-induced synovitis. Results of histologic examination confirmed that denervation was an effective method for transecting the innervation of the craniolateral and caudolateral aspects of the hip joint capsule. CONCLUSIONS AND CLINICAL RELEVANCE In this study, minimally invasive denervation did not result in gait modifications in dogs. Denervation did not abolish the signs of pain and lameness associated with generalized induced synovitis of the hip joint. Further studies are required before conclusions can be drawn regarding the clinical usefulness of hip joint denervation for dogs with hip dysplasia.

Functional outcome measures in a surgical model of hip osteoarthritis in dogs

Background

The hip is one of the most common sites of osteoarthritis in the body, second only to the knee in prevalence. However, current animal models of hip osteoarthritis have not been assessed using many of the functional outcome measures used in orthopaedics, a characteristic that could increase their utility in the evaluation of therapeutic interventions. The canine hip shares similarities with the human hip, and functional outcome measures are well documented in veterinary medicine, providing a baseline for pre-clinical evaluation of therapeutic strategies for the treatment of hip osteoarthritis. The purpose of this study was to evaluate a surgical model of hip osteoarthritis in a large laboratory animal model and to evaluate functional and end-point outcome measures.

Methods

Seven dogs were subjected to partial surgical debridement of cartilage from one femoral head. Pre- and postoperative pain and functional scores, gait analysis, radiographs, accelerometry, goniometry and limb circumference were evaluated through a 20-week recovery period, followed by histological evaluation of cartilage and synovium.

Results

Animals developed histological and radiographic evidence of osteoarthritis, which was correlated with measurable functional impairment. For example, Mankin scores in operated limbs were positively correlated to radiographic scores but negatively correlated to range of motion, limb circumference and 20-week peak vertical force.

Conclusions

This study demonstrates that multiple relevant functional outcome measures can be used successfully in a large laboratory animal model of hip osteoarthritis. These measures could be used to evaluate relative efficacy of therapeutic interventions relevant to human clinical care.

Electronic supplementary material

The online version of this article (doi:10.1186/s40634-016-0053-5) contains supplementary material, which is available to authorized users.

Nutritional Assessment

Nutritional assessment focuses on evaluation of animal-specific, diet-specific, feeding management, and environmental factors. Assessment includes evaluation of a patient's medical history, comprehensive diet history, and physical examination including body weight, body condition, and muscle condition. Diagnostic testing may identify comorbidities associated with obesity or concurrent health conditions that need to be considered when developing a nutrition plan. When obesity is diagnosed during the nutritional assessment this finding along with health implications must be clearly communicated to the pet owner. Careful consideration of animal-specific, diet-specific, owner-specific, and environmental factors allows the clinician to develop a specific nutrition plan tailored to the needs of pet and owner.

Obesity, Exercise and Orthopedic Disease

Osteoarthritis is common among aging canine and feline patients. The incidence and severity of clinical lameness are closely correlated to body condition in overweight and obese patients. Excessive adiposity may result in incongruous and excessive mechanical loading that worsens clinical signs in affected patients. Data suggest a potential link between adipokines, obesity-related inflammation, and a worsening of the underlying pathology. Similarly, abnormal physical stress and generalized systemic inflammation propagated by obesity contribute to neurologic signs associated with intervertebral disc disease. Weight loss and exercise are critical to ameliorating the pain and impaired mobility of affected animals.

Obesity Treatment: Environment and Behavior Modification

Obesity is commonly encountered in veterinary patients. Although there are various published dietary approaches to achieving weight loss, successful long-term prevention of weight regain has proven elusive. Adding environmental and behavioral treatment strategies to a weight loss plan may help the veterinary team, the pet, and the pet owner maximize the effectiveness of the program. Because the owner directly affects the environment and behavior of the pet undergoing a weight loss plan, treatment strategies with an emphasis on owner involvement is the focus of this review. Veterinary use of the 5 A's behavioral counseling approach with the pet owner is discussed.

Diagnosis, prevention, and management of canine hip dysplasia: a review

Canine hip dysplasia (CHD) is a polygenic and multifactorial developmental disorder characterized by coxofemoral (hip) joint laxity, degeneration, and osteoarthritis (OA). Current diagnostic techniques are largely subjective measures of joint conformation performed at different stages of development. Recently, measures on three-dimensional images generated from computed tomography scans predicted the development of OA associated with CHD. Continued refinement of similar imaging methods may improve diagnostic imaging techniques to identify dogs predisposed to degenerative hip joint changes. By current consensus, joint changes consistent with CHD are influenced by genetic predisposition as well as environmental and biomechanical factors; however, despite decades of work, the relative contributions of each to the development and extent of CHD signs remain elusive. Similarly, despite considerable effort to decipher the genetic underpinnings of CHD for selective breeding programs, relevant genetic loci remain equivocal. As such, prevention of CHD within domestic canine populations is marginally successful. Conservative management is often employed to manage signs of CHD, with lifelong maintenance of body mass as one of the most promising methods. Surgical intervention is often employed to prevent joint changes or restore joint function, but there are no gold standards for either goal. To date, all CHD phenotypes are considered as a single entity in spite of recognized differences in expression and response to environmental conditions and treatment. Identification of distinct CHD phenotypes and targeting evidence-based conservative and invasive treatments for each may significantly advance prevention and management of a prevalent, debilitating condition in canine companions.

Surface Electromyography of the Vastus Lateralis, Biceps Femoris, and Gluteus Medius Muscle in Sound Dogs During Walking and Specific Physiotherapeutic Exercises

OBJECTIVE

To analyze the muscle activity patterns of the vastus lateralis (VL), biceps femoris (BF), and gluteus medius (GM) during walking and specific physiotherapeutic exercises in clinically sound, healthy dogs without lameness.

STUDY DESIGN

Observational study.

ANIMALS

Clinically sound dogs (n = 10).

METHODS

Surface electromyography was performed during walking and exercises (11% incline and decline, walking over cavaletti) within a defined study area. The maximal, minimal, and mean muscle potentials reflecting activity during each motion cycle were compared among the exercises.

RESULTS

During swing phase, maximal VL activity was higher during cavaletti walking compared with walking over ground or incline. Cavaletti walking had an earlier occurrence of the maximum VL activity than did walking over ground or decline. Compared with walking over ground, incline walking had higher minimal GM activity during the 1st half of stance phase and an earlier occurrence of maximal activity during the 2nd half of stance phase. Cavaletti walking had earlier maximal GM activity in swing phase than did walking over ground. Differences between decline and incline walking were seen in all 3 phases of the motion cycle; namely, higher minimal and mean activities occurred during incline walking, and higher maximum activity occurred in the 1st half of stance phase during incline walking. Compared with decline walking, cavaletti walking showed higher minimal and mean activities in the 2nd half of stance phase and higher maximal and mean activities in swing phase.

CONCLUSION

Cavaletti and incline walking exercises increases the VL and GM muscle activity.

Nutrition of aging dogs

Aging is a normal process characterized by a variety of physiologic changes. Geriatric dogs are also more likely to be afflicted with certain disease conditions. Both normal and abnormal physiologic changes associated with aging in the dog may be amenable to nutritional intervention. Specific alterations in nutrients or in dietary characteristics can be beneficial; however, these are best done in the context of an individualized nutritional assessment and monitoring paradigm.

Pet obesity management: beyond nutrition

Excess weight has been associated with many clinical and subclinical conditions that put a pet's health at risk. Successful weight management programs extend beyond standard nutritional management and incorporate an understanding of human-animal interaction. Understanding the processes and dynamics of human-animal relationships can be a useful tool for practitioners in developing successful treatment plans for their clients. Obesity is a nutritional disorder requiring lifelong management; however, when veterinarians go beyond standard treatment to include an understanding of human-animal interaction, it is also one of the few conditions in veterinary medicine that is completely preventable and curable.

Therapeutic options for the treatment of chronic pain in dogs

Chronic pain is a widely recognised problem in humans and is being increasingly recognised as a significant problem in dogs. Whilst a large number of therapies are described and utilised to treat chronic pain in dogs, there is a severe shortage of evidence to guide practitioners in selection of treatments. Until more evidence becomes available, practitioners should adopt a cautious approach, utilising licensed treatments first when possible. Non-pharmacological therapies should be incorporated into the chronic pain management plan whenever possible. Given the probable prevalence of chronic pain in dogs there is an urgent need for research to identify effective treatments.

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.

The challenges of assessing osteoarthritis and postoperative pain in dogs

The challenge of measuring pain in veterinary medicine is compounded by the lack of fully validated, reliable methods to measure and assess pain in nonverbal patients. In human medicine, there are numerous, validated pain assessment tools (PATs) for assessing various, specific types of pain. The advances in human medicine pain management and numerous validated pain scales should serve as incentives and templates to facilitate similar advances in the development of validated PATs for use in dogs (and other species). The limited number of canine PATs constrains our ability to adequately and reliably assess pain. Improving the ability to quantify osteoarthritis and postoperative pain in dogs would enhance the development of analgesics for animals, advance the management of animal pain, facilitate the use of animal pain models in preclinical trials for human analgesics, and provide insight into the quantification of pain responses in humans who lack the ability to adequately communicate. This review describes the need for practical, valid, and reliable PATs for use in veterinary patients and discusses some currently available PATs commonly used to evaluate acute and chronic pain in dogs.

Nano total hip replacement in 12 dogs

OBJECTIVE

To determine the short-term clinical outcome of nano total hip replacement (NanoTHR) in dogs.

STUDY DESIGN

Retrospective case series.

ANIMALS

Dogs (n = 12).

METHODS

Medical records (2009-2011) of dogs that had nano-THR were reviewed for signalment, weight, clinical signs, side, age, prosthesis sizes, concurrent surgeries performed, complications, operative time, 3-month postoperative pelvic radiograph results, and lameness scores.

RESULTS

Breeds were Yorkshire Terriers (n = 6), Toy Poodles (2), with 1 each of Maltese, Pomeranian, Cavalier King Charles Spaniel, and Shih-Tzu. Median body was 4.87 kg (range, 2.5-5.90 kg) and median age, 35.75 months (range, 12-144 months). Radiographs were taken in 4 dogs at 12 days (n = 2), 14 days (1), and 30 days (1) after surgery because of presentation for an acute grade 5 lameness. Three dogs had femoral fractures distal to the femoral implant tip and 1 dog displaced the acetabular implant medially. After revision surgery, all femoral fractures were assessed as healed with intact plate fixation. The dog with the medially displaced acetabular component responded to conservative management including strict confinement and analgesic administration. Eight dogs (58%) were assigned a grade 1 lameness and 4 dogs were grade 2 (33%) at 12-week examination. The 3 dogs with grade 5 lameness scores found to have femoral fractures within 1 month after surgery, subsequently improved to grade 1 (n = 1) and 2 (2) 12 weeks after revision surgery. The dog with medial acetabular displacement improved to a grade 2 lameness 12 weeks after conservative management.

CONCLUSIONS

Although all 12 dogs had good-to-excellent outcomes, 33% experienced significant complications associated with the technique. As improvements in instrumentation and refinements in the technique are developed, NanoTHR can be considered an alternative to the femoral head and neck ostectomy (FHO) or medical management of coxofemoral disease for toy breed dogs. Further studies with a larger number of dogs and longer follow-up times are required.

Surgical management of radial head luxation in a dog using an external skeletal traction device

A five-month-old Airedale Terrier was presented with a history of right thoracic limb lameness. Clinical and radiographic examinations revealed caudolateral luxation of the right radial head. Surgical intervention involved an oblique proximal radial osteotomy and gradual craniomedial traction of the radial head using an external skeletal fixator (ESF) incorporating a traction device. The radial head was gradually reduced over 16 days. After radiographic confirmation of appropriate radial head reduction, a consolidation phase followed, with removal of the traction ESF after 24 days. Follow-up radiographs documented remodelling of the radial head. Clinical follow-up three years postoperatively revealed nearly normal ground reaction forces. Activity was unrestricted and there was no requirement for analgesic medications.

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 (S_R ≥ ±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.

Nutritional care for aging cats and dogs

Veterinarians need to be prepared to provide nutritional advice for healthy pets as well as for pets that are ill. Before instituting a dietary change in any patient, especially an older dog or cat, a nutritional evaluation should be completed. This should include an evaluation of the patient, the current diet, and feeding management. Diets should be appropriate to the unique needs of the individual patient. Many diseases in senior pets are “diet-sensitive” meaning that diet can play a role in managing the effects of the disease. Common examples discussed include cognitive dysfunction of aging, osteoarthritis, and obesity.

Treatment of hip dysplasia

Hip dysplasia is a common orthopaedic developmental disorder of dogs. This paper reviews the treatment options available for management of the condition in the skeletally immature and adult dog.

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.

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.

The effects of weight loss on adipokines and markers of inflammation in dogs

Evidence suggests that adipose tissue-derived adipokines induce mild inflammation and may play a role in insulin resistance associated with diabetes. The present study was designed to examine a series of adipokines and markers of inflammation in dogs before and after a successful weight loss. The study included fasting serum samples from twenty-five dogs before and after a weight-loss programme. Serum C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP-1) were measured as indicators of chronic inflammation, while serum adipokines including total adiponectin, high-molecular-weight (HMW) adiponectin, resistin and leptin were also examined. Medians for CRP (before, 10·0 (interquartile range 5·4–15·0) μg/ml; after, 5·6 (interquartile range 3·8–7·0) μg/ml) and MCP-1 (before, 212 (interquartile range 157–288) ng/ml; after, 185 (interquartile range 143–215) ng/ml) decreased significantly after weight loss. Medians for resistin showed a mild, yet significant reduction (before, 67·1 (interquartile range 44·4–88·5) pg/ml; after, 60·5 (interquartile range 32·3–67·1) pg/ml), while leptin showed a dramatic decrease after weight loss (before, 18·9 (interquartile range 10·8–35·4) ng/ml; after, 6·6 (interquartile range 3·9–10·2) ng/ml). Serum total adiponectin and HMW adiponectin were unchanged on all analyses performed. These data suggest that weight loss can decrease chronic inflammation; however, the clinical implications of this decrease are not well elucidated in dogs. Surprisingly, there was no increase in total or HMW serum adiponectin after weight loss, as observed previously in human subjects. The lack of change in total and HMW adiponectin might explain why insulin resistance and type 2 diabetes are less prevalent in obese dogs when compared with humans and cats.

A cross sectional study of the prevalence and risk factors for owner misperception of canine body shape in first opinion practice in Glasgow

The objectives of the study were to investigate whether owners were able to assign the correct body shape to their dog and to assess the dog and owner level factors associated with incorrect owner assessment of dog body shape. Six hundred and eighty questionnaires were administered to dog owners in 5 first opinion practices around Glasgow during July 2007. At the same time, the interviewer and owner assessed the body shape of each dog. The interviewer assessment of body shape was taken as the gold standard. Incorrect owner assessment of dog body shape (misperception) was divided into two groups: underestimation and overestimation. Multinomial logistic regression and classification and regression trees (CART) were used to assess risk factors associated with each type of misperception. Misperception of dog body shape was present in 44.1% of owners with underestimation (i.e. the owner considered the animal to have a leaner body shape from the gold standard assessment) being the most common form of misperception. Risk factors identified by both multinomial logistic regression and CART were gender of owner, age of the dog and dog body shape. The classification tree appeared to have improved predictive ability when compared to the multinomial model.

Assessment of veterinary practitioners in the British Isles' approaches towards the management of canine osteoarthritis

The aim of this questionnaire-based retrospective study was to ascertain veterinary practitioners in the British Isles' approaches to osteoarthritis in dogs. The Mann-Whitney U test, Kruskal-Wallis test and multiple ordinal logistic regression were used to compare demographic data with treatment options. Questionnaires were returned by 228 practitioners (a response rate of 22.8 per cent). The majority of responses were from males (70 per cent). Eighty-six per cent (188 of 220) of the respondents had graduated from veterinary schools in the UK and Ireland. Veterinarians who had graduated less recently used exercise modulation less frequently (P<0.004, odds ratio [OR]=1.06) and ranked exercise modulation as less important (P=0.008, OR=1.04). Veterinarians who had graduated outside the UK or Ireland were less likely (P=0.033, OR=0.46) to use exercise modulation than those who had graduated in the UK or Ireland. Veterinarians who had graduated more recently were less likely (P=0.008, OR=0.95) to use medications. Female veterinary surgeons were less likely to rank medications as important (P<0.0001, OR=0.29) and less likely to rank corticosteroids as important (P=0.046, OR=0.42) than male veterinary surgeons. Practitioners who had graduated outside the UK or Ireland were less likely (P=0.01, OR=0.30) to rank corticosteroids as important. There was a significant mild negative correlation between the frequency of use of structure-modifying osteoarthritis drugs (SMOADs) and practitioners' opinions on rank importance (-0.32, P<0.0001). Medications such as SMOADs and nutraceuticals were ranked as not important but were used frequently. Overall, age, sex, the university of graduation and the number of canine consultations per day had an impact on the practitioners' treatment protocols.

Synovitis in dogs with stable stifle joints and incipient cranial cruciate ligament rupture: a cross-sectional study

OBJECTIVE

To evaluate stifle joints of dogs for synovitis, before development of joint instability and cranial cruciate ligament rupture (CrCLR).

STUDY DESIGN

Cross-sectional study.

ANIMALS

Dogs (n = 16) with CrCLR and stable contralateral stifles; 10 control dogs with intact CrCL.

METHODS

Arthritis and tibial translation were graded radiographically. Synovitis severity and cruciate pathology were assessed arthroscopically. Presence of inflammatory cells in synovial membrane biopsies was scored histologically. CrCLR stifle pairs and control stifles were compared.

RESULTS

Radiographic evidence of arthritis, cranial tibial translation, and arthroscopic synovitis were increased in unstable stifles, when compared with stable contralateral stifles in CrCLR dogs (P < .05). Arthroscopic synovitis in both joints of CrCLR dogs was increased compared with controls, was correlated with radiographic arthritis (S(R) = 0.71, P < .05), and was present in all stable contralateral stifles. Arthroscopically, 75% of stable stifle joints had CrCL fiber disruption, which correlated with severity of synovitis (S(R) = 0.56, P < .05). Histologic evidence of synovitis was identified in all CrCLR dogs, but was only significantly correlated with arthroscopic observations in stable stifles (r(2) = 0.57, P < .005).

CONCLUSION

Synovitis is an early feature of the CrCLR arthropathy in dogs before development of joint instability clinically. Severity of synovitis is correlated with radiographic arthritis in joints with minimal to no clinically detectable CrCL damage.

Micro total hip replacement for dogs and cats: surgical technique and outcomes

OBJECTIVE

To describe the surgical technique for the micro total hip replacement (Micro THR) system and report clinical outcomes.

STUDY DESIGN

Prospective study.

ANIMALS

Dogs (n=49) and cats (n=8) with coxofemoral arthropathy.

METHODS

Small breed dogs and cats with coxofemoral arthritis were enrolled for Micro THR. Patient data were recorded. Implant positioning and cement mantle quality were evaluated radiographically. Orthopedic examinations and client interviews were used to assess outcome.

RESULTS

Micro THR was performed unilaterally (40 dogs, 8 cats) and staged bilaterally (9 dogs) to resolve pain associated with osteoarthritis or trauma. Mean body weight was 7.2 kg. Postoperative complications included prosthesis luxation (9), cup aseptic loosening (1), and sciatic neurapraxia (1). Mean radiographic follow up was 96.1 weeks; 10 joints were followed for ≥3.0 years. Sixty of the 66 (91%) Micro THRs had excellent outcomes. Two dogs (<2.75 kg) were too small for the prosthesis and 4 dogs with unmanageable luxation had explantation.

CONCLUSIONS

Micro THR is considered a satisfactory procedure for management of small breed dogs and cats with coxofemoral disease unresponsive to medical management.

CLINICAL RELEVANCE

Micro THR is a viable option to treat disabling disorders of the hip. More than 170 cat and small dog breeds, and many mixed breeds, could benefit from Micro THR surgery.

Evaluation of a therapeutic diet for feline degenerative joint disease

BACKGROUND

Feline degenerative joint disease (DJD) is common and there are no approved therapies for the alleviation of the associated pain.

OBJECTIVE

To test a diet high in eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) content and supplemented with green-lipped mussel extract and glucosamine/chondroitin sulfate (test-diet) for its pain-relieving and activity-enhancing effects in cats with painful, mobility-impairing DJD over a 9-week period.

ANIMALS

Forty client-owned cats.

METHODS

Randomized, controlled, blinded, parallel group, prospective clinical study. Cats with no detectable systemic disease, and with at least 1 appendicular joint with radiographic evidence of DJD where manipulation elicited an aversive response were included. Cats were randomly allocated to the test-diet or control diet (C-diet). Outcome measures were subjective owner and veterinarian assessments, and objective activity monitoring (accelerometry). Nonparametric statistics were used to evaluate changes within and between groups for both subjective and objective data, and locally weighted scatterplot smoothing regression analysis was used to predict activity changes.

RESULTS

The primary objective outcome measures indicated that activity declined significantly (P < .001) in the C-diet group, significantly increased (P < .001) in the test-diet group and there was a significant difference between the groups (P < .001).

CONCLUSION AND CLINICAL IMPORTANCE

A diet high in EPA and DHA and supplemented with green-lipped mussel extract and glucosamine/chondroitin sulfate improved objective measures of mobility. Dietary modulation might be 1 method to use to improve mobility in cats with DJD-associated pain.

The effect of weight loss on lameness in obese dogs with osteoarthritis

This paper describes the effect of weight loss on lameness in obese dogs with osteoarthritis (OA). Fourteen obese client-owned dogs with clinical and radiographic signs of OA participated in an open prospective clinical trial. After a screening visit and a visit for collection of baseline data, the dogs were fed a restricted-calorie diet over a study period of 16 weeks that incorporated six follow-up visits. At each visit, body weight and pelvic circumference were measured and severity of lameness was assessed using a numeric rating scale (NRS), a visual analogue scale (VAS) and kinetic gait analysis. This is the first study to assess both subjectively and objectively, the effect of weight loss alone on lameness in obese dogs with OA. The results indicate that body weight reduction causes a significant decrease in lameness from a weight loss of 6.10% onwards. Kinetic gait analysis supported the results from a body weight reduction of 8.85% onwards. These results confirm that weight loss should be presented as an important treatment modality to owners of obese dogs with OA and that noticeable improvement may be seen after modest weight loss in the region of 6.10 – 8.85% body weight.

Ability of the canine brief pain inventory to detect response to treatment in dogs with osteoarthritis

OBJECTIVE

To determine whether the Canine Brief Pain Inventory (CBPI) can detect changes in dogs with osteoarthritis treated with an NSAID or a placebo.

DESIGN

Double-blind, randomized, placebo-controlled clinical trial.

ANIMALS

70 dogs with osteoarthritis.

PROCEDURES

Owners completed the CBPI on day 0. Dogs received carprofen or a placebo on days 1 through 14. Owners completed the CBPI again on day 14. Pain severity and pain interference scores from the CBPI were calculated, and the change from day 0 to day 14 was assessed within each group and between groups.

RESULTS

No significant differences were detected in median scores for pain severity (3.50 and 3.25 on days 0 and 14, respectively) and pain interference (3.92 and 3.25 on days 0 and 14, respectively) in dogs receiving the placebo. Dogs receiving carprofen had significant changes in median scores for pain severity (4.25 to 2.25 on days 0 and 14, respectively) and pain interference (4.33 to 2.67 on days 0 and 14, respectively).There was a significantly greater improvement in pain severity and pain interference scores in dogs treated with carprofen, compared with improvement in scores for dogs receiving the placebo.

CONCLUSIONS AND CLINICAL RELEVANCE

The CBPI was able to detect improvements in pain scores in dogs with osteoarthritis treated with an NSAID or a placebo. These results, in combination with previous reliability and validity testing, support the use of the CBPI to obtain quantifiable assessments from owners regarding the severity and impact of chronic pain and treatment for dogs with osteoarthritis.

Relationship between objective and subjective assessment of limb function in normal dogs with an experimentally induced lameness

OBJECTIVE

To evaluate the relationship between previously used subjective and objective measures of limb function in normal dogs that had an induced lameness.

STUDY DESIGN

Prospective, blinded, and induced animal model trial.

ANIMALS

Normal, adult, and mixed-breed dogs (n=24) weighing 25-35 kg.

METHODS

Force platform gait analysis was collected in all dogs before and after induction of lameness. All gait trials were videotaped; 60 video trials were evaluated by 3 surgeons with practice limited to small animal orthopedics and 3 first year veterinary students in an effort to establish the relationship between subjective and objective measures of lameness. Evaluators were unaware of the force platform data.

RESULTS

Concordance coefficients were low for all observers and were similar between students and surgeons. These values were further decreased when normal and non-weight bearing trials were removed. Agreement with the force platform data was low even when observers only had to be within +/-10% of the ground reaction forces. When repeat trials were evaluated surgeons had a much higher repeatability compared with students.

CONCLUSIONS

Subjective evaluation of the lameness in this study varied greatly between observers and agreed poorly with objective measures of limb function.

CLINICAL RELEVANCE

Subjective evaluation of gait should be interpreted cautiously as an outcome measure whether performed from a single or from multiple observers.