If you need a more accessible version of this website, click this button on the right. Switch to Accessible Site

WARNING

You are using an outdated browser. Please upgrade your browser to improve your experience.

Close [x]
(207) 846-6515 H
H

(207) 846-6515

ORTHOPEDICS: HIP DYSPLASIA


Hip Dysplasia


Basics
OVERVIEW
The failure of normal development (known as "malformation") and gradual deterioration, leading to loss of function, (known as "degeneration") of the hip joints (known as the "coxofemoral joints")
The hip joint is composed of the "ball" (known as the "femoral head") and the "socket" (known as the "acetabulum")
Genetics
Complicated pattern of inheritance, multiple genes involved (known as "polygenetic transmission")
Development of hip dysplasia determined by an interaction of genetic and environmental factors
Some breeds are more likely to have the genes for hip dysplasia than other breeds


Signalment/Description of Pet
Species
Dogs-one of the most common skeletal diseases seen in dogs
Cats-incidence is significantly lower than in dogs
Breed Predilections
Large-breed dogs-Saint Bernards, German shepherd dogs, Labrador retrievers, golden retrievers, rottweilers
Smaller breed dogs-may be affected; less likely to show clinical signs
Cats-more commonly affects purebred cats; reportedly affects approximately 18% of Maine coon cats
Mean Age and Range
Begins in the immature dog
Clinical signs-may develop after 4 months of age or may develop later due to osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage)
Predominant Sex
Dogs-none
Cats-more common in female cats than male cats


Signs/Observed Changes in the Pet
Depend on the degree of joint looseness or laxity; degree of osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage); and duration of the disease
Early disease-signs related to joint looseness or laxity
Later disease-signs related to joint degeneration and osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage)
Decreased activity
Difficulty rising
Reluctance to run, jump, or climb stairs
Intermittent or persistent hind-limb lameness-often worse after exercise
"Bunny-hopping" or swaying gait
Narrow stance in the hind limbs
Painful hip joints
Joint looseness or laxity-characteristic of early disease; may not be seen in long-term (chronic) hip dysplasia due to arthritic changes in the hip joint
Grating detected with joint movement (known as "crepitus")
Decreased range of motion in the hip joints
Loss of muscle mass (known as "atrophy") in thigh muscles
Enlargement (known as "hypertrophy") of shoulder muscles; occurs because dog puts more weight on front legs as it tries to avoid weight on its hips, leading to extra work for the shoulder muscles and subsequent enlargement


Causes
Genetic susceptibility for hip looseness or laxity
Rapid weight gain, nutrition level, and pelvic-muscle mass-influence development and progression of hip dysplasia


RISK FACTOR
Overweight and poor muscle tone


Treatment
Health Care
May treat with conservative medical therapy or surgery
Outpatient, unless surgery is performed
Depends on the pet's size, age, and intended function; severity of joint looseness or laxity; degree of osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage); veterinarian's preference for treatment; and financial considerations of the owner
Physiotherapy (passive joint motion)-decreases joint stiffness; helps maintain muscle integrity
Swimming (hydrotherapy)-excellent form of physical therapy; encourages joint and muscle activity, without increasing the severity of joint injury
ACTIVITY
As tolerated by the pet
Swimming-recommended to maintain joint mobility, while minimizing weight-bearing activities
Diet
Weight control-important; decreases the pressure applied to the painful joint as the pet moves; minimize weight gain associated with reduced exercise
Special diets designed for rapidly growing large-breed dogs-may decrease severity of hip dysplasia
SURGERY
Triple Pelvic Osteotomy (TPO) or Double Pelvic Osteotomy
Corrective orthopedic surgical procedure; designed to re-establish corresponding surfaces (known as "congruity") between the "ball" (femoral head) and the "socket" (acetabulum) making up the hip joint
Immature pet (6-12 months of age) is surgical candidate
Rotate the "socket" (acetabulum)-to improve coverage of the "ball" (femoral head); correct forces acting on the joint; minimize the progression of osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage); may allow development of a more normal joint, if performed early (before joint deterioration or degeneration develops)

Juvenile Pubic Symphysiodesis

Surgical procedure to fuse the pubis (part of the pelvis) bones together

The pelvis develops from matching bones on the right- and left-side of the body; the area where the two sides meet is composed of cartilage and is called a "symphysis"; the pubis is a part of the pelvis; the surgical procedure fuses the pubic symphysis at an early age (using electrocautery)

Causes the "socket" (acetabulum) to better cover the "ball" (femoral head)
Improves relationship of corresponding surfaces of the joint and joint stability-similar effects as TPO, without surgical metal implants
Minimal postoperative problems; easy to perform-must be performed very early (3-4 months of age) to achieve effect; minimal effect achieved if performed after 6 months of age
Total Hip Replacement
Indicated to salvage joint function in mature dogs, with severe osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage) that is unresponsive to medical therapy
Pain-free joint function-reported in more than 90% of cases
Hip joint replacement in only one leg provides acceptable function in approximately 80% of cases
Complications-dislocation (luxation); damage to the sciatic nerve; infection
Excision Arthroplasty
Surgical removal of the "ball" part of the hip joint
Removal of the "ball" (femoral head and neck) to eliminate joint pain; the muscles "act" as the joint
Primarily a salvage procedure-for significant osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage)-when pain cannot be controlled medically or when total hip replacement is cost-prohibitive
Best results-small, light dogs (weighing less than 20 kg or 44 lbs); pets with good hip musculature
Slightly abnormal gait often persists following surgery
Postoperative loss of muscle mass (muscle atrophy) in the hind limbs-common, particularly in large dogs
Medications
Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive
Pain-relieving drugs (known as "analgesics") and anti-inflammatory drugs-minimize joint pain (and thus stiffness and loss of muscle mass [muscle atrophy] caused by limited usage); decrease inflammation of the lining of the joint (known as "synovitis"); drugs that relieve pain and decrease inflammation include carprofen; etodolac; deracoxib
Medical therapy-does not correct the structural or biomechanical abnormality; deterioration or degeneration of the hip joint likely to progress; medical therapy often provides only temporary relief of signs
Glucosamine and chondroitin sulfate-may have a cartilage protective effect in osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage)
Follow-Up Care
Patient Monitoring
Monitor signs, degree of lameness, and changes seen on x-rays (radiographs)-assess progression
Medical treatment-if poor response or initial response is followed by deterioration of condition, change the dosage of medication or try a different medication or consider surgical intervention
Triple pelvic osteotomy-monitored by x-rays (radiographs), taken periodically; assess healing, metal-implant stability, reestablishment of corresponding surfaces between the "ball" (femoral head) and the "socket" (acetabulum) making up the hip joint (that is, joint congruence), and progression of osteoarthritis (form of joint inflammation [arthritis] characterized by chronic deterioration or degeneration of the joint cartilage)
Hip replacement-monitored by x-rays (radiographs); assess metal implant stability

Preventions and Avoidance

Best prevented by not breeding dogs affected with hip dysplasia

Pelvic x-rays (radiographs)-may help identify dogs with actual bony changes of hip dysplasia; may not identify all dogs carrying the genes for the disease
Do not repeat dam-sire breeding that result in affected offspring
Special diets designed for rapidly growing large-breed dogs-may decrease severity of hip dysplasia
Expected Course and Prognosis
Joint deterioration or degeneration usually progresses-most pets lead normal lives with proper medical or surgical management
Key Points
Hip dysplasia has a genetic (inherited) basis, involving multiple genes
Development of hip dysplasia determined by an interaction of genetic and environmental factors
Medical therapy is designed to relieve signs (known as "palliative therapy"); it does not "cure" the disease, because the joint instability is not corrected
Joint deterioration or degeneration often progresses, unless a corrective orthopedic surgical procedure is performed early in the disease
Surgical procedures can salvage hip-joint function once severe joint deterioration or degeneration occurs

Blackwell's Five-Minute Veterinary Consult: Canine and Feline, Fifth Edition, Larry P. Tilley and Francis W.K. Smith, Jr. © 2011 John Wiley & Sons, Inc.

Office Hours

DayOpenClose
Monday7:306:00
Tuesday7:306:00
Wednesday7:306:00
Thursday7:306:00
Friday7:306:00
Saturday8:0012:00; Also, 4 pm Boarding Pick-up
Sunday4:00pmBoarding Pick-up
Day Open Close
Monday Tuesday Wednesday Thursday Friday Saturday Sunday
7:30 7:30 7:30 7:30 7:30 8:00 4:00pm
6:00 6:00 6:00 6:00 6:00 12:00; Also, 4 pm Boarding Pick-up Boarding Pick-up