Hip dysplasia is a skeletal defect in dogs. In hip dysplasia, the ball portion (femoral head) of the hip is not securely seated in the socket portion (acetabulum). This condition is especially common in working and sporting breeds of dogs. Certain breeds are definitely predisposed . (see chart from the Orthopedic Foundation for Animals further down this page)

Hip dysplasia is an inherited problem which is not usually present at birth. It develops within the first 6-8 months of life. The exact cause is unknown, but it is generally accepted that the condition is from the combined action of an unknown number of genes. Nutrition and environment are also believed to be contributing factors.

Concerned dog breeders and veterinarians have tried to reduce the incidence of hip dysplasia through selective breeding. X-rays has been performed on potential breeding pairs in an effort to determine the status of the hip joints. Some progress has been made toward reducing the severity and incidence of canine hip dysplasia, but progress has been slow.

Hip dysplasia is defined as a biomechanical disease. That is, the muscles do not develop and reach maturity at the same rate as the bones. Since the hip depends on muscle power to be stable, it can pull apart and trigger a series of events resulting in hip dysplasia.

If a pup is so poorly developed that it cannot walk, then the demands of the musculoskeletal support system are greater than the strength of the surrounding musculature. The muscles and ligaments are unable to maintain the needed relationship between the femoral head and the acetabulum. This results in a partial or incomplete dislocation of the femoral head. The acetabulum is unable to develop properly if the femoral head is dislocated, and is shallower than normal when the pup reaches maturity. When the femoral head is dislocated, its cartilage covering is subjected to wear and tear. This eventually leads to a miss-shaped femoral head , and osteoarthritis or degenerative joint disease.

The degree of hip dysplasia (mild, moderate, or severe) does not effect the signs exhibited by the affected dog. Signs may range from no symptoms to a pronounced disability. Symptoms can appear any time after 4 weeks of age, but are generally not detected, except in severe cases, until after 6 months of age.

Clinical signs of canine hip dysplasia include:

  • Lameness after prolonged exercise
  • A waddling or swaying gait
  • Morning stiffness
  • Difficulty in standing up
  • Reluctance to move
  • Change in temperament
  • Pain when moving the hip joints.
  • Limping

These signs often appear worse on cold damp days.

Early clinical signs are caused by the stretching and tearing of the joint. This pain may disappear as scar tissue forms, and the puppy seems to get better. Unfortunately arthritis continues to get worse and eventually signs of pain appear again. Early treatment will slow or stop the development of arthritis.

The diagnosis of canine hip dysplasia is bases upon: history, symptoms, a complete physical exam, and X-rays. X-rays are necessary to confirm hip dysplasia. They can show:

  • the shape and depth of the acetabulum
  • the shape contour and position of the femoral head
  • degenerative joint disease.

Treatment

Hip dysplasia can be treated surgically, medically, or a combination of both. There is no cure for hip dysplasia, but with appropriate veterinary care affected dogs can live long, healthy, active lives. Non-surgical treatment can include:

  • enforced cage rest when the dog is experiencing discomfort
  • mild analgesics
  • anti-inflammatory drugs.

There are several surgical procedures that can be attempted in young dogs, and if the disease is not severe:

  • Cutting of the femur and/or the pelvis and repositioning the joint. This is recommended for dogs 6-12 months of age only.
  • Cutting the pectineus muscle. This is useful in relieving pain in certain cases, but has no effect upon the progression of the disease.
  • Removal of the femoral head and neck. and formation of a “false joint” between the proximal femur and the pelvic musculature. Small and medium sized dogs usually do better with this procedure than larger dogs.
  • Total hip replacement. Although this procedure is expensive, many dogs are able to return to full activity .

HOW PREVALENT IS HIP DYSPLASIA

Any dog can have displasia. But, based on test results from the Orthopedic Foundation for Animals, the highest incidence of dysplasia is as follows:

1.Bulldog
2.Otterhound
3.Cumberland Spaniel
4.St. Bernard
5.Boykin Spaniel
6.American Bulldog
7.Newfoundland
8.Staffordshire Terrier
9.BullMastiff
10.Bloodhound
11.Fila Brasileiro
12.Chesapeake Bay REtriever
13.Gordon Setter
14.Goldon Retriever
15.Chow Chow
16.Field Spaniel
17.Staffordshire Bull Terrier
18.Rottweiler
19.Kuvasz
20.Norwegian Elkhound
21.Mastiff
22.Giant Schnauzer
23.Old English Sheepdog
24.German Shephard
25.Bernese Mountain Dog
26.English Setter
27.Spinone
28.American Pit Bull Terrier
29.Beagle
30.Welsh Corgi Pembroke
31.Welsh Springer Spaniel
32.Black and Tan Coonhound
33.Shih Tzu
34.Briard
35.Brittany
36.Greater Swill Mountain Dog
37.Welsh Corgi Cardigan
38.Bouvier Des Flandres
39.English Springer Spaniel
40.Irish Water Spaniel
41.Pudel Pointer
42.Portugese Water dog
43.Curley Coated Retriever
44.Akita
45.Chinese Shar Pei
46.Australian Cattle Dog
47.Airdale Terrier
48.Poodle
49.Leonberger
50.Komondor
51.Labrador Retriever
52.Irish Setter
53.Alaskan Malamute
54.Great Dane
55.Border Collie
56.Anatolian Shepherd
57.Munsterland
58.Boxer
59.Samoyed
60.Akbash Dog
61.Tibetan Mastiff
62.Cavalier King Charles Spaniel
63.Puli
64.Great Pyrenees
65.German Wirehaired Pointer
66.Weimaraner
67.Standard Schnauzer
68.Nova Scotia Ducktolling Retriever
69.English Pointer
70.Kerry Blue Terrier
71.American Water Spaniel
72.American Eskimo dog
73.Vizsla
74.Shiba Inu
75.Lhasa Apso
76.Wirehaired Pointing Griffon
77.Petit Basset Griffon Vendeen
78.Keeshond
79.Bearded Collie
80.Cocker Spaniel
81.Rhodesian Ridgeback
82.Tibetan Terrier
83.Doberman Pinscher
84.Australian Shepherd
85.Belgian Malinois
86.Irish Wolfhound
87.English Cocker Spaniel
88.Bichon Fiese
89.German Shorthaired Pointer
90.Afghan Hound
91.Dalmatian
92.Shetland Sheepdog
93.Finnish Spitz
94.Flat coated Retriever
95.Border Terrier
96.Soft Coated Wheaten Terrier
97.Belgian Tervuren
98.Greyhound
99.Cannan
100.Basenji
101.Collie
102.Belgian Sheepdog
103.Ibizan Hound
104.Schipperke
105.Pharaoh Hound
106.Siberian Husky
107.Saluki
108.Borzoi
109.Main Coon Cat