top of page
Writer's pictureDr Andrew Matole, BVetMed, MSc

What is Dysplasia?

Updated: May 28, 2023

In medicine, the term "dysplasia" is used to describe the improper growth or development of cells, tissues, or organs. It is frequently regarded as a precancerous condition because it shows cellular alterations that, if ignored, could develop into cancer. The body's epithelial tissues, such as the skin and organ linings, as well as bone, cartilage, and other tissues are all susceptible to dysplasia.


Under a microscope, dysplastic cells stand out as being aberrant. In comparison to normal cells, they may exhibit variations in size, shape, organization, and general structure. The normal operation of the damaged tissue or organ may be interfered with by these alterations.


Normal cells, Neoplastic cells, abnormal and excessive growth of cells; Dysplastic cells, abnormality of development, and differentiation.

Specifically, the term "dysplasia" with reference to pets refers to a condition known as developmental dysplasia, which primarily affects the skeletal system, particularly the joints, though other systems can also be impacted. Although it can happen to other animals as well, it is frequently observed in particular breeds of dogs and cats.


What predisposes Dysplasia?

 

Dysplasia in pets is frequently impacted by genetic causes, but environmental variables including quick growth, rapid weight gain, and inadequate nourishment can also cause it to occur.

Dysplasia can occur in a variety of medical situations and is frequently linked to the emergence of particular cancer types. For instance, cervical dysplasia is usually associated with human papillomavirus (HPV) infection and, if ignored, can develop into cervical cancer. Similar to this, colon dysplasia can result in colorectal cancer. The most well-known types of dysplasia in pets are those that affect the corresponding joints, hip dysplasia and elbow dysplasia. These diseases are characterized by abnormal growth and misalignment of the bones that comprise the joint, which causes instability in the joint, pain, and other symptoms. However, because dysplasia is a tissue maldevelopment, it can also impact certain organ subsections, including those of the kidneys, heart, and eyes..


How is a Dysplasia Classified?

 

Depending on the degree and severity of cellular abnormalities, dysplasia is frequently divided into distinct classes. The tissue that is affected by the dysplasia and its specific type determines the grading system. Mild, moderate, and severe dysplasia are common grades.


How is a dysplasia detected?

 

Clinical signs, physical examinations, and diagnostic imaging, such as X-rays or ophthalmoscopic examination, can all be employed to determine the presence of dysplasia in a particular tissue, organ or body system.


What are the common dysplasia in pets?

 

 

Normal hip joint
Normal hip joint

Larger dog breeds including German Shepherds, Labrador Retrievers, and Great Danes are more likely to have hip dysplasia.

Dog X Ray Showing Canine Bilateral Hip Dysplasia. Ventral View.
Dog X Ray Showing Canine Bilateral Hip Dysplasia. Ventral View.

The ball (femoral head) and socket (acetabulum), which make up the hip joint, are malformed and do not fit together properly. This makes the joint loose, which eventually results in joint degeneration, inflammation, and osteoarthritis.


 

Normal elbow joint
Normal elbow joint

On the other side, elbow dysplasia, which affects the elbow joint, is frequently observed in large and giant dog breeds.

X-ray showing elbow dysplasia in a dog
X-ray showing elbow dysplasia in a dog

Osteochondritis dissecans (OCD), ununited anconeal process, fractured coronoid process, and others are included in this general term. Elbow dysplasia results in painful, limping, and dysfunctional joints by causing improper growth and development of the elbow joint.


3. Shoulder dysplasia

 

An illustration showing the shoulder joints bones
An illustration showing the shoulder joints bones

Shoulder dysplasia is an uncommon congenital defect of development marked by excessive laxity of the shoulder joint. It is a malformation of the shoulder joint that results in shallow glenoids, flattened humeral heads, generalized forelimb lameness, and slight discomfort with shoulder extension. As the musculature around the affected area matures, the discomfort or lameness typically gets better. However, the dog is more likely to develop subsequent osteoarthritic alterations in the afflicted joint(s) because of the instability.


4. Retinal dysplasia

 

An illustration showing retinal dysplasia with retinal detachment
An illustration showing retinal dysplasia with retinal detachment

Retinal dysplasia is a condition where the retina develops and grows abnormally, leading to rosettes, folds, and even retinal detachment. It is inherited in many dogs, while acquired versions result from insults received during pregnancy or soon after birth. In mild cases of this dysplasia, there are no clinical symptoms, but in severe cases, blindness occurs. Skeletal chondrodysplasia is present in another variety of this dysplasia.

Chondrodysplasia is a short-legged phenotype characteristic of many dog breeds. Chondrodystrophy, a separate mutation, also includes a short-legged phenotype as well as premature disc degeneration and increased susceptibility to disc herniation.

5. Renal dysplasia

Renal dysplasia is a genetic condition that runs in some dog breeds and is inherited in an autosomal recessive manner. Renal failure is caused by the immature and other inappropriate structures that result from the improper kidney tissue development.


The dog breeds affected include Airedale, Alaskan Malamute, Beagle, Bedlington Terrier, Boxer, Bulldog, Chow Chow, Golden Retriever, Great Dane, Pyrenean Mountain Dog, Irish Wolfhound, Keeshond, King Charles Spaniel, Lhasa Apso, Miniature Schnauzer, Old English Sheepdog, Pekingese, Samoyed, Shih Tzu, Soft Coated Wheaten Terrier, Poodle (Standard Poodle)


 

The tricuspid valve and its accompanying components, such as the papillary muscles and chordae tendineae, are all affected by a congenital condition known as tricuspid valve dysplasia (TVD). 2% of all congenital disorders in dogs include this unusual congenital heart ailment, according to one study. The Labrador Retriever, Boxer, and Great Dane breeds of large breed dogs are most frequently found to have tricuspid valve dysplasia (TVD). Cats may infrequently exhibit tricuspid valve dysplasia (TVD). Tricuspid valve dysplasia (TVD) results in right cardiac hypertrophy, tricuspid regurgitation, and, in extreme cases, right heart failure.



How are dysplasias treated?

 

Weight management
Weight management

While dysplasia in animals cannot be totally healed, there are a number of therapy alternatives to control the illness and enhance the animal's quality of life. Treatment options include managing the pet's weight, altering  the pet's exercise routine, providing physical therapy to  the pet, using painkillers, and, in extreme circumstances, undergoing joint reconstruction surgery.

A dog about to receive treatment in a veterinary clinic
A dog about to receive treatment in a veterinary clinic

For quick intervention and management, routine screening and early dysplasia identification are essential. Treatment options may include observation, medication, surgical removal of aberrant tissue, or other focused therapies, depending on the extent and location of dysplastic alterations.


It is crucial to speak with a veterinarian who can make a correct diagnosis and suggest the best course of action if you have concerns about your pet's joint health or suspect that they may have dysplasia.


References

 

Smith GK, Mayhew PD, Kapatkin AS, McKelvie PJ, Shofer FS, Gregor TP. Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in German Shepherd Dogs, Golden Retrievers, Labrador Retrievers, and Rottweilers. J Am Vet Med Assoc. 2001 Dec 15;219(12):1719-24. doi: 10.2460/javma.2001.219.1719. PMID: 11767921.


Cook CR, Cook JL. Diagnostic imaging of canine elbow dysplasia: a review. Vet Surg. 2009 Feb;38(2):144-53. doi: 10.1111/j.1532-950X.2008.00481.x. PMID: 19236671.


Bruder MC, Shoieb AM, Shirai N, Boucher GG, Brodie TA. Renal dysplasia in Beagle dogs: four cases. Toxicol Pathol. 2010 Dec;38(7):1051-7. doi: 10.1177/0192623310382558. Epub 2010 Sep 30. PMID: 20884818.


Famula TR, Siemens LM, Davidson AP, Packard M. Evaluation of the genetic basis of tricuspid valve dysplasia in Labrador Retrievers. Am J Vet Res. 2002 Jun;63(6):816-20. doi: 10.2460/ajvr.2002.63.816. PMID: 12061526.


Evans PJ. Shoulder dysplasia in a Labrador. J Small Anim Pract. 1968 Feb;9(2):55-8. doi: 10.1111/j.1748-5827.1968.tb04588.x. PMID: 5689175.


Goldstein O, Guyon R, Kukekova A, Kuznetsova TN, Pearce-Kelling SE, Johnson J, Aguirre GD, Acland GM. COL9A2 and COL9A3 mutations in canine autosomal recessive oculoskeletal dysplasia. Mamm Genome. 2010 Aug;21(7-8):398-408. doi: 10.1007/s00335-010-9276-4. Epub 2010 Aug 5. PMID: 20686772; PMCID: PMC2954766.


American Kennel Club (AKC) - Canine Health Foundation: Website: https://www.akcchf.org/canine-health/your-dogs-health/disease-information/hip-dysplasia/

Provides information about hip dysplasia in dogs, including causes, symptoms, diagnosis, treatment, and prevention.


Orthopedic Foundation for Animals (OFA): Website: https://www.ofa.org/diseases/hip-dysplasia

OFA is a registry that evaluates and grades hip and elbow dysplasia in dogs. Their website offers detailed information about hip dysplasia, including genetic testing and breed-specific statistics.


The goals of the database are to reduce the incidence of inherited disorders in dogs by providing information to owners and breeders, and to facilitate the best management possible of these conditions by providing current information to veterinarians.

71 views0 comments

Recent Posts

See All

Komentáře


bottom of page