sign in sign up
<<
Home , Affenpinscher, Clumber Spaniel, Dogue de Bordeaux, Dog anatomy, Elbow dysplasia, English Shepherd

A Fresh Look at an Old Problem: How to Best Manage Limping ? Denis Marcellin-Little, DEDV

Synopsis There is no standardized method used by all clinicians to diagnose the source of lameness in dogs. Clinicians are left to pick and chose what they do and when. The result is less than ideal. Many orthopedic problems in dogs stay undiagnosed for long periods of time. Also, the conservative or surgical management of orthopedic problems is not always commensurate with its severity: many therapies have minimal effectiveness and many effective therapies are not routinely implemented. It is in everyone’s best interest (the patient, the owner, and the veterinarian) to adopt a more proactive approach to the identification and management of orthopedic problems in dogs. That proactive approach includes owner education (hint: a handful of deeply rooted myths must be debunked), the development of more accurate palpation skills, and the establishment of convenient and sustainable long-term management programs for orthopedic problems that are managed conservatively. This presentation sets up the stage for successful early identification and long-term management of orthopedic problems in dogs.

Introduction Too often, (OA) is diagnosed when middle-aged dogs become exercise-intolerant or have difficulties performing their activities of daily living. Yet, most dogs with OA live with the disease for years before they are identified. The lengthy delay in the identification OA is a glaring sign that we need to rethink our approach to the identification of orthopedic problems in dogs.

Owner education A clear lack of knowledge regarding orthopedic diseases in dogs combined with a number of orthopedic myths complicate the identification and management of orthopedic problems in dogs. Many owners are unfamiliar with basic and joint physiology and with concepts such as polygenic developmental orthopedic diseases, the phenotypic expression of faulty genes, the influence of external factors such as growth rate on the phenotypic expression of a polygenic disease, the idea of screening to detect a disease because it becomes visibly obvious, the concept of treating joint disease very promptly to avoid irreversible negative consequences, the impact of specific nutrients (protein, energy, calcium) on growth, the impact of having a lean body weight over a lifetime, the use of exercise to strengthen or stretch, etc. These facts influence the and the management of orthopedic problems. They can be discussed at a level that can be understood by all dog owners.

Also, several orthopedic myths are prevalent. For example, owners tend to think that orthopedic problems tend to affect older dogs more than younger dogs (an anthropomorphic belief based on the fact that older humans have more orthopedic problems such as osteoporosis and OA than younger humans), that orthopedic problems in growing dog tends to be mild and self-correcting or self-limiting (another anthropomorphic belief, based on the fact that most orthopedic injuries in children can be managed with temporary protection [rest] or joint immobilization [cast or brace]), that catching a flying disc and retrieving a tennis ball are healthy forms of exercise, that increased exercise can lead weight loss in dogs that are overfed, that dogs left unsupervised in a fenced-in backyard exercise spontaneously, that adjunctive therapies can ‘treat’ the late stages of OA, etc. Owner education is a lengthy process that requires repeated interactions over time.

Screening patients Veterinarians and owners must be aware of the risk of orthopedic disease in their dogs. A good first step is to assess the reported prevalence of dysplasia, dysplasia, and patellar luxation on the web site of the Orthopedic Foundation for Animals (Table 1). From these data, 1 dog in 5 has , 1 in 6 has , and one in sixteen has patellar luxation. Several breeds carry an extremely high risk of hip or elbow dysplasia. Hip dysplasia can also be evaluated more proactively and accurately using the PennHIP screening method (Table 2). Because of the biases and potential false negative results present in databases such as OFA, it may be more scientifically valid to compare the relative risk of orthopedic problem based on other sources, such as large review of patients treated by veterinarians. In a report of > 1.2 million dogs available in the Veterinary Medical Database, Newfoundland was 5.77 times more likely to have hip dysplasia and 3.77 times more likely to have a cranial cruciate ligament injury than dogs as a whole.1

Table 1. Prevalence of hip dysplasia, elbow dysplasia, and patellar luxation among breeds screened by the Orthopedic Foundation for Animals (source: OFA.org, accesses January 18, 2017).*

Rank Hip dysplasia Elbow dysplasia Patellar luxation Breed Prevalence (%) Breed Prevalence (%) Breed Prevalence (%)

1 71.8 47.8 Pomeranian 36.2 2 70.3 Pug 43.6 Yorkshire ** 23.4 3 Dogue de bordeaux 57.4 38.9 19.0 4 Neapolitan 51.3 Bulldog 34.7 Tibetan 11.8 5 49.3 32.4 11.6 6 St. Bernard 49.1 31.7 English toy spaniel 10.1 7 Brussels griffon 45.5 Otterhound 28.7 9.6 8 43.7 Bernese mountain dog7 27.6 Mi-ki 9.3 9 Boerboel 42.7 20.0 Chow chow 8.6 10 Black russian terrier 42.2 Chinese shar-pei 25.2 8.5 11 40.3 Newfoundland 23.7 8.5 12 Basset 39.5 Dogue de bordeaux 20.6 8.0 13 39.1 20.4 Russian tsvetnaya bolonka 7.5 14 Perro de 38.3 Sussex spaniel 20.0 Lowchen 7.1 15 Argentine dogo 38.2 dog 19.3 Portuguese podengo pequeno 7.0 16 Fila brasileiro 37.8 18.7 Toy 6.5 17 American bulldog 36.3 Am. staffordshire terrier 16.8 Chinese shar-pei 6.0 18 35.2 Staffordshire 16.5 5.7 19 Maine coon cat 33.8 Cane corso 16.3 5.6 20 Boykin spaniel 30.8 15.8 Biewer terrier 5.6 21 30 15.7 5.6 22 27.8 St. Bernard 15.7 5.5 23 Am. staffordshire terrier 26.4 American terrier 15.6 Pug 5.5 24 26.2 English 15.6 Nederlandse 5.5 25 Newfoundland 25.9 Mastiff 15.4 5.5 26 Spanish 25.8 14.8 French bulldog 5.4 27 25.6 Bloodhound 14.6 Norfolk terrier 5.1 28 Bullmastiff 25.4 14.5 5.0 29 American pit bull terrier 23.8 13.6 Brussels griffon 5.0 30 22.3 12.9 4.9 31 Cardigan 21.8 Glen of imaal terrier 12.3 4.8 32 Shiloh shepherd 21.6 11.4 Petit basset griffon vendéen 4.8 33 Rottweiler 21.2 Golden 11.2 4.6 34 Chow chow 21.1 Greater swiss mountain dog 11.1 4.4 35 Louisiana catahoula leopard 20.8 10.5 Bulldog 4.4 36 Mastiff 20.7 9.6 frise 4.3 37 20.6 9.5 Puli 4.1 38 20.6 9.4 3.9 39 German shepherd dog 20.5 Belgian malinois 9.3 3.9 40 20.3 Soft coated wheaten terrier 8.8 terrier 3.7 41 White shepherd 20.2 Clumber spaniel 8.6 3.6 42 20.1 8.3 3.5 43 20.0 Giant 8.2 3.4 44 19.9 Shiloh shepherd 7.0 West highland white terrier 3.4 45 Hybrid 19.3 6.8 Chinese crested 3.4 46 Gordon setter 19.2 Afghan hound 6.7 Cockapoo 3.3 47 19.2 Kuvasz 6.4 Am. hairless terrier 3.3 48 Kuvasz 19.1 6.3 Labrador retriever 3.3 49 Greater swiss mountain dog 18.5 6.2 Maltese 3.2 50 Affenpinscher 18.3 Rhodesian ridgeback 6.2 Papillon 3.1

Total : 107,256 of 497,515 21.6 Total : 42,413 of 263,993 16.1 Total: 2,303 od 35,938 6.4

* List limited to the 50 breeds with the highest prevalence, with > 100 dogs evaluated within each breed. Breeds listed in all categories are in bold font. They include Bulldog, Pug, and Chow chow. ** Fourteen terrier breeds are included in the 50 breeds with highest prevalence of patellar luxation.

Table 2. Example of PennHIP report for a Lagotto Romagnolo dog.

The Lagotto Romagnolo dog in this report had a distraction index of 0.62. Sixty to seventy percent of dogs within that breed had tighter and twenty to thirty percent had looser hips.

Assessing the true impact of orthopedic disease on dogs The impact of orthopedic diseases on dogs vary greatly over time from a mild and intermittent lameness to a complete loss of ability to stand or walk (Figure 1). Yet, we tend to treat dogs based on their disease rather than the severity of their problem.

Figure 1. These two dogs have approximately the same age, the same size and are from comparable breeds. They both have chronic orthopedic diseases. The Golden Retriever on the left is asymptomatic and is shown trotting comfortably. The Labrador Retriever on the right perceives severe pain in both of his pelvic limbs and is shifting most of his weight to his forelimbs. The Golden Retriever has hip dysplasia and the Labrador Retriever has partial tears to both of his cranial cruciate ligaments.

Background information should include a report on the severity of the orthopedic problems. Questions should include: How is the functioning? What are the dog’s limitations? What triggers the lameness? How severe is it? How long does it last? The assessment of the severity of an orthopedic problem includes observation of the dog resting, getting up, standing, walking, and trotting, palpation of the affected limbs, and (radiographic) imaging. Is the dog demeanor altered: Is the dog unwilling or unable to perform specific activities? Is the dog reluctant to play or exercise? Often, owners of dogs that have received a total prosthesis report that their dog is “acting like a ” because the dog had lost its willingness to play as a result of chronic hip dysplasia and chronic pain.

Chronic orthopedic problems, particularly OA, have classic stages:

STAGE 1. Growing dogs or young adults show intermittent signs lasting a few seconds or a few minutes Growing dogs with developmental orthopedic diseases may have hind limb lamenesses (with hip laxity, patellar luxation) or forelimb lamenesses (with elbow subluxation, elbow dysplasia, OCD of the shoulder joint). The lameness is often mild. It may be intermittent or constant. The clinical signs of early joint disease, however, are often ill defined: being generally slower, clumsier, less playful, and having a “funny” gait. Unfortunately, joint disease is often overlooked or missed at that stage in life. It is missed because owners and clinicians often think of growing dogs as being very healthy. Also, they may falsely attribute the lameness to “growing pains” or “pulling a muscle.” As OA enters its chronic phase, the clinical signs of joint disease become more discrete and more intermittent. They may become bilateral, too, and bilateral lameness is seemingly more difficult to detect than unilateral lameness. When signs subside, owners and caregivers often forget the period of lameness and no longer worry about the potential presence of a chronic orthopedic disease.

STAGE 2. Young adult dogs have intermittent signs lasting a few hours Young adult dogs with joint disease often have intermittent signs that subside after a night of rest. These signs are often associated with more intense periods of activity—for example, with a sudden burst of activity (the “weekend warrior syndrome”). OA may or may not be diagnosed during this second stage. The likelihood of diagnosing OA appears to vary between specific joints. Some diseases are much easier to visualize than others. For example, it is easier to detect hip subluxation on ventrodorsal radiographs of the than to detect humeroradial subluxation on radiographs of the elbow joint. Also, dog owners and clinicians tend to be much more aware of hip dysplasia than elbow dysplasia. Surprisingly, there is not a lot of difference between the number of dogs with hip dysplasia and elbow dysplasia (Table 1).

STAGE 3. Adult dogs become exercise intolerant and show difficulties performing activities of daily living Middle-aged dogs with OA progressively become exercise intolerant. They may sit when taking a leash walk. They hesitate or refuse to climb into a motor vehicle or to climb stairs. The changes present at that stage of OA are more profound: damage is major, the joint capsule is thickened and may restrict the motion of the arthritic joint (i.e., hip extension is limited, elbow flexion is limited, stifle joint extension is limited), and dogs often have lost muscle mass in affected limbs. A pain response to joint motion (hyperflexion, hyperextension) or to joint loading (galloping, jumping) is much more likely to be present at that stage. OA flares are easier to trigger, are more severe, last longer, and are harder to control with therapy. OA is often diagnosed at that third stage because the clinical and radiographic signs are more obvious, severe, and persistent.

STAGE 4. Older dogs lose the ability to walk The fourth stage is the most severe OA stage. It most often involves geriatric dogs that are losing the ability to walk and perform activities of daily living. The changes present in limbs with OA are similar to changes present in the third stage: loss of articular cartilage, thickening of the joint capsule, and pain present when joints are loaded or when joint capsules are stretched. The loss of muscle mass is more severe. Dogs, particularly overweight dogs, progressively lose the ability to walk. Because most households are not prepared or able to care for a dog with limited mobility, the loss of ability to walk because of OA is one of the key causes of euthanasia in large dogs, if not the main cause of euthanasia. In a lifelong study of seven litters of Labrador , the loss of ability to walk because of OA was the leading cause of end of life.7 For some dogs, the loss of ability to walk occurs much earlier in life.

Setting up a management plan adapted to the situation Owners’ expectations for the dog are a key to setting up an effective management program.

When is needed? Surgery is needed to relieve pain (that cannot be managed by non-surgical means) (THR), to restore a functional limb (fracture, joint luxation, joint instability), or to positively impact the progression of a disease. Few positively impact the course of orthopedic diseases. For example: a segmental ulnar ostectomy can improve the congruity of the elbow joint in young growing dogs with elbow subluxation as a result of a premature closure of the distal ulnar growth plate. The juvenile pubic symphysiodesis can improve the stability of the hip joint in a young dog with hip laxity. Let’s face it, most orthopedic surgical procedures not aimed at repairing long- fractures are not particularly effective or are not proven to be effective over the long term. Let’s look at the four most common orthopedic diseases for example. The scientific evidence that the surgical stabilization of cranial cruciate ligament injuries offers a superior long-term outcome than conservative management is very thin. There is no evidence that dogs that undergo stabilization of a do better in the long-term. There is no evidence that dogs that undergo the removal of a fragmented medial coronoid process or an osteochondral flap do better. There is no evidence that dogs that undergo femoral head ostectomies walk and feel better than dogs with hip dysplasia that are managed conservatively. That lack of evidence may be due in part to the fact that lameness and functional impairment in dogs are generally loosely defined and assessed subjectively. If dogs are assessed subjectively before their management, the effectiveness of that management cannot be determined. What should we do then? We should strive to assess dogs as objectively as possible. We should strive to describe the impairment resulting from orthopedic problems as objectively as possible.

Interventions should be proportionate to the severity of the disease. In other words, it seems ill advised to perform an irreversible surgery in dogs that have mild clinical signs or whose clinical signs developed a few days before their examination. For example, one should not consider doing a in a dog with signs of hip dysplasia that are mild, recent, and easily controlled with rest and NSAIDs. The same rationale applies to the medical management of chronic orthopedic problems in dogs: Simple therapeutic measures should be implemented at first, and more complex or costly measures should be considered for the later stages of the disease. This will ensure that the therapy is adapted to the stage of the disease and that it can be sustained over a long period. Therapeutic interventions must focus on modalities and processes that have proven benefits in dogs or in humans rather than modalities and processes without proven benefits. The anticipated cost and owner involvement for long-term management of orthopedic problems should be discussed. Ineffective management options decrease owners’ trust in the medical team and decrease owners’ ability to pay for effective treatment strategies. Similar to OA management in humans, three management options for OA in dogs stand out because they offer clear and unequivocal benefits: NSAIDs, weight optimization, and regular exercise. The evidence for efficacy of these three forms of treatment is far greater than the potential efficacy of all other forms of treatment. These options have a solid safety record, with a low rate of side effects and complications. Their cost, compared to other forms of management, is also very reasonable and sustainable by many owners. NSAID therapy is most convenient among these three options because, unlike exercise and weight optimization, NSAID administration does not require significant lifestyle changes (e.g., walking daily with a dog or dramatically changing the dog’s food intake). NSAID therapy is described below.

Weight Optimization Weight optimization is extremely effective when managing OA in dogs. Weight optimization includes avoiding excessively rapid growth during the first year of life because rapid growth increases the likelihood that dogs that have the genes responsible for developmental orthopedic diseases will express these genes. In other words, dogs with faulty genes responsible for a specific orthopedic disease (i.e., OCD, elbow dysplasia, hip dysplasia) are more likely to see these faulty genes expressed if they grow rapidly rather than slowly. The process of eating freely with an unlimited amount of food available is called ad libitum feeding. A limited food intake generally represents approximately 75% of the food consumed during ad libitum feeding. Dogs with such limited food intake grow much less rapidly than dogs eating ad libitum, but their adult size does not differ from dogs that grew more rapidly. Weight optimization is also critical for adult dogs. Many dogs are overweight or obese. OA progresses much more rapidly in overweight dogs than in dogs that are not overweight. Also, the clinical signs of OA decrease when overweight dogs lose weight.

Exercise Exercise is also a key strategy used to manage OA. While exercise intuitively means that arthritic joints are going to have to do more work, exercise under controlled conditions is beneficial to arthritic joints. Controlled exercise maintains muscular and cardiovascular fitness over an extended period. Exercise only has limited value for weight management, and it should not be the sole strategy used to promote weight loss because exercise cannot overcome excesses in caloric intake. Weight loss should be achieved and sustained with dietary adjustments (that may be supported by the increase in basal metabolism induced by exercise). Exercise is a long-term strategy that can maintain fitness at the first and second stages of OA and regain fitness at the third and fourth stages of OA in dogs. In a study involving Labrador retrievers with hip dysplasia conducted by our research group, lameness scores were lower in dogs that were exercising more: Dogs that exercised > 1 hour/day had a lameness score that was 30% lower than the dogs that exercised < 20 minutes per day.2

During the first and second stages of OA, dogs are naturally fit, and multiple exercise options are available. Their goals are to maintain muscular and cardiovascular fitness and joint motion (through regular exercise) and to avoid OA flares (through controlled exercise). Members of the clinical team (veterinarians and veterinary technicians) play a key role in identifying these exercises, in training the dog to perform them, and in training their owners to continue the exercise plan with their dogs. For these dogs, most of the exercises are home based. For dogs in the third stage of OA, exercise is aimed at recovering fitness and joint motion to boost exercise tolerances. Members of the clinical team should take a more active role in the selection of appropriate exercises and the implementation of the program. Similar to programs for dogs in the first and second stages of OA, the programs are initiated in the clinic and then transition toward home-based programs to control their cost and sustain the efficacy over a long period. For dogs in the fourth stage of OA, exercise programs should be more cautiously implemented and should have more modest goals. Aquatic exercises may be more effective than land-based exercises. Ambulation assistance and weight optimization may be necessary before exercises can be performed. Exercises for dogs with limited mobility are more technically challenging than exercises in dogs with less severe OA, and the transition toward home-based exercise is more progressive and challenging. Dogs with OA that are effectively managed may never reach the fourth stage of the disease.

References Full-text of these references and can be accessed from a Google Drive folder until April 1, 2017 at this link: https://drive.google.com/open?id=0B42fOpwAkxItQnBOcG5kcHRaMXM

1. Witsberger TH, Villamil JA, Schultz LG, et al. Prevalence of and risk factors for hip dysplasia and cranial cruciate ligament deficiency in dogs. J Am Vet Med Assoc 2008;232:1818-1824. 2. Greene LM, Marcellin-Little DJ, Lascelles BD. Associations among exercise duration, lameness severity, and hip joint range of motion in Labrador Retrievers with hip dysplasia. J Am Vet Med Assoc 2013;242:1528-1533.