Hypertrophic Osteodystrophy (HOD)
This page is for educational purposes only and is not a substitute for veterinary diagnosis or emergency care. Always consult your primary veterinarian or a rehabilitation veterinarian before starting treatment. If your pet cannot walk, has sudden paralysis, severe pain, or breathing difficulty, seek urgent veterinary attention.
What is Hypertrophic Osteodystrophy (HOD)?
Also known as: HOD; metaphyseal osteopathy; skeletal scurvy (historical misnomer).
HOD affects the metaphyses of long bones in immature, typically large- and giant-breed dogs. Inflammation and disruption of bone formation produce swelling, severe pain, and lameness that may involve multiple limbs. Many puppies are febrile, lethargic, and inappetent — this is more than “growing pains.”
Radiographs classically show a radiolucent line in the metaphysis parallel to the physis (“double physis” appearance) in established cases. Cause is multifactorial and not fully defined; infectious, genetic, and nutritional hypotheses appear in literature. Veterinary diagnosis excludes septic arthritis, panosteitis, and trauma.
Treatment is supportive: pain control, nursing care, nutrition, and management of systemic signs. Severe cases may need hospitalisation. Rehabilitation, when the puppy is cleared, supports gentle mobility and prevents secondary complications from prolonged recumbency — never aggressive loading during acute disease.
Common signs to watch for
Signs vary by severity and by whether your pet is a dog or cat. Owners of dogs often notice:
- Warm, painful swelling near the ends of long bones (wrists, hocks, knees, elbows)
- Reluctance or inability to stand; shifting or multi-limb lameness
- Fever, lethargy, reduced appetite
- Depression or vocalising when handled
- In severe cases: dehydration and marked systemic illness
Causes & contributing factors
- Developmental metaphyseal osteopathy of uncertain exact trigger
- Predisposition in rapidly growing large and giant breeds
- Possible associations discussed with recent vaccination, diet, or infection in some reports — interpretation belongs with your veterinarian
- Not caused by simple “too much exercise” alone
How veterinary rehabilitation helps
In the acute febrile phase, priorities are veterinary medical care and nursing — not intensive physio. Soft bedding, assisted standing when appropriate, and passive range to prevent contracture may be guided carefully.
As systemic signs settle, gentle rehab helps restore confidence in standing, walking, and muscle activation without overloading healing metaphyses.
Owners receive education on pacing growth-period activity and monitoring for relapse.
Rehabilitation plans at RehabVet are individualised after a veterinary assessment. We coordinate with your primary vet when imaging, medication, or surgery is part of the overall plan.
Modalities & services commonly used at RehabVet
Depending on your pet’s examination findings, comfort, and goals, a plan may include one or more of the following:
Expected rehabilitation goals
Goals are set for the individual patient. Typical aims may include (not guarantees — outcomes vary):
- Support comfort and basic mobility during recovery
- Prevent pressure sores and joint contracture during illness
- Rebuild strength gradually after veterinary clearance
- Educate owners on flare recognition and activity limits
- Coordinate with ongoing medical and nutritional plans
We do not publish invented success percentages. Progress is tracked clinically (gait, strength, range of motion, pain behaviours, and home function) and plans are adjusted over time.
When to seek veterinary care
- Any puppy with fever, swollen limbs, and refusal to walk — urgent veterinary care
- Inability to rise, severe pain, or not eating/drinking
- Rapidly worsening multi-limb lameness
- Suspected relapse after a prior HOD episode
- Is HOD contagious?
HOD itself is not treated as a simple contagious disease like kennel cough. Your vet will still rule out infectious differentials that can look similar.
- Will my puppy outgrow HOD?
Many puppies improve with supportive care as they mature, but episodes can be severe and occasionally recurrent. Prognosis is individual — follow your veterinarian’s guidance.
- Can hydrotherapy help during acute HOD?
Not during febrile, systemically ill phases. Aquatic work is only considered later, if at all, when your vet confirms the puppy is stable and loading is appropriate.
Related reading & patient stories
Book a rehabilitation assessment
If your pet has been diagnosed with HOD, or you are noticing mobility changes, our team can assess and design a multimodal rehab plan.
Educational content only — not a diagnosis. For emergencies, contact your nearest veterinary hospital.