Line 1: |
Line 1: |
| [[Image:Hypertrophic osteodystrophy.jpg|right|thumb|100px|<small><center>Hypertrophic osteodystrophy (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] | | [[Image:Hypertrophic osteodystrophy.jpg|right|thumb|100px|<small><center>Hypertrophic osteodystrophy (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]] |
− | *Also called - '''metaphyseal osteopathy'''
| + | Also known as: '''''Metaphyseal Osteopathy — HOD''''' |
− | *Young (usually 3-6 months old), fast growing '''dogs''' of large or giant breeds
| + | |
− | *'''Distal radius and ulna''' most severely affected
| + | ==Introduction== |
− | *Clinical signs:
| + | This is a '''developmental disease''' of '''young, large, rapidly-growing large and giant breeds''' such as the Great Dane, St Bernard, Irish Setter, Labrador, German Shepherd, Doberman and Weimaraner. |
− | **Fever
| + | |
− | **Anorexia
| + | It most frequently presents at the age of '''3-4 months''' (range 2-8) and '''males''' are affected more commonly than females. |
− | **Severe lameness
| + | |
− | **Swelling in '''metaphyses''' of long bones corresponding with neutrophilic infiltrate
| + | The disease occurs at the metaphysis of long bones, especially the '''distal ulna and radius'''. |
− | *Radiologically:
| + | |
− | **Increased lucency and increased density areas in metaphyses
| + | The aetiology of the condition is '''unknown''', but theories include: an excessive plane of nutrition, calcium/phosphate imbalance, vitamin C deficiency or an '''infectious agent'''. |
− | **Enlarged metaphyses
| + | |
− | *Usually bilaterally symmetrical
| + | ==Clinical Signs== |
− | *Histologically:
| + | Respiratory or gastrointestinal illness may precede the onset of skeletal disease. |
− | **Haemorrhage and necrosis of [[Bones - Anatomy & Physiology|osteoblasts]] in the growth plates and primary spongiosa
| + | |
− | **Intense infiltration by [[Neutrophils|neutrophils]]
| + | Clinical signs vary from '''mild lameness to severe systemic illness''', pyrexia, depression, inappetance, weight loss and inability to stand. |
− | **Periosteal reaction + formation of new bone on external surface above the lesion
| + | |
− | *Many resolve spontaneously with complete remodelling and healing of the bone
| + | '''Pain''' can be elicited by digital pressure on the metaphysis. |
− | *Can progress to '''periosteal bone proliferation'''
| + | |
− | *Cause is unknown
| + | The condition is usually '''bilaterally symmetrical''' and may affect all four limbs. |
− | **Unlikely to be dietary deficiency
| + | |
− | **Likely to be infectious cause
| + | In severe cases, the long bone metaphyses are visibly '''swollen, hot and painful on palpation'''. |
− | *Contrast with [[Panosteitis|'''canine panosteitis''']]
| + | |
| + | Active periods of disease may last for several days and '''relapses''' may occur at intervals of 1-6 weeks. |
| + | |
| + | Some severely suffering dogs may '''die''' or may be euthanised on owner's request. |
| + | |
| + | ==Diagnosis== |
| + | The clinical signs and presentation are suggestive. |
| + | |
| + | '''Radiography''' can confirm the diagnosis. Findings include: |
| + | :irregular radiolucent line (double physeal line) in the metaphysis, parallel to the normal radiolucent physeal line |
| + | :the physis may appear widened |
| + | :subperiosteal new bone formation at the metaphysis forming a collar of bone, also known as bone cuffing |
| + | :evidence of growth deformities |
| + | |
| + | Bone '''scintigraphy''' may reveal increased uptake of agent at the metaphysis. |
| + | |
| + | Haematology and biochemistry are usually unremarkable. |
| + | |
| + | '''Histology''' of the area would reveal: haemorrhage and necrosis of [[Bones - Anatomy & Physiology|osteoblasts]] in the growth plates and primary spongiosa, intense infiltration by [[Neutrophils|neutrophils]], periosteal reaction and formation of new bone on external surface above the lesion. |
| + | |
| + | ==Treatment== |
| + | HOD is usually '''self-limiting''' and mildly affected dogs '''recover within a few weeks'''. |
| + | |
| + | Treatment involves '''supportive care with proper nutrition, fluids and analgesia'''. |
| + | |
| + | Buffered aspirin is the preferred analgesic. |
| + | |
| + | In severe cases, '''corticosteroids and antibiotics''' may be indicated, depending on blood culture results. Recumbent puppies should be turned every 4 hours and placed in a well-padded cage. |
| + | |
| + | Correction of '''angular limb deformities''' may be necessary. |
| + | |
| + | ==Prognosis== |
| + | This is related to disease severity. |
| + | |
| + | '''Mildly affected dogs''' have a '''good prognosis''' and many recover spontaneously. Diaphyseal deformities can be severe but are usually not debilitating. |
| + | |
| + | '''Severely affected dogs''' have a '''poor prognosis''' and some dogs can succomb to '''hyperthermia or acidosis'''. Euthanasia may also be performed on the worst cases. |
| + | |
| + | {{Learning |
| + | |flashcards = [[Small Animal Orthopaedics Q&A 04]] |
| + | }} |
| + | |
| + | ==References== |
| + | Pasquini, C. (1999) '''Tschauner's Guide to Small Animal Clinics''' ''Sudz Publishing'' |
| + | |
| + | Dunn, J. (1999) '''Textbook of small animal medicine''' ''Elsevier Health Sciences'' |
| + | |
| + | Hosgood, G. (1998) '''Small animal paediatric medicine and surgery''' ''Elsevier Health Sciences'' |
| + | |
| + | [[Category:To Do - Helen]] |
| + | [[Category:To Do - Review]] |
| + | |
| | | |
| [[Category:Bones - Hyperplastic Pathology]] | | [[Category:Bones - Hyperplastic Pathology]] |