Musculoskeletal 3 Flashcards
What is Wolff’s law?
Changes in shape and size occur to accomodate altered mechanical loading and compression
What are the three main portals of entry into bone?
- Spread from ingectious foic in contiguous tissues
- Hematogenous route via nutrient arteries
- Direct implantation secondary to trauma or surgery
What is the name of the group of conditons that are shown below and what is the cause of them?
Chondrodysplasia - widespread abnormality of growth cartiladge. Localised in some breeds chondrodysplasia
- chondrodysplasia - defect in the cartiladge template - malformation of chondrocytes + ECM in which they lie
What is the name of the condition shown below and what is the cause of it?
Osteopetrosis - defect in osteoclast function - assist in lining the primary spongiosa - creating an area that is favourable for osteoblasts to lay down osteoid
Provide an example of a cause of osteopetrosis from each of the following categories - inherited, infectious disease, toxic
- Inherited - SLC4A2 mutation in cattle
- Infectious disease - CDV, BVDV, growth retardation lattice
- Toxic - lead
What are the three main causes of angular limb deformities?
- Asymmetric lesion invovling growth plate –> failure of endochondral ossification
- Abnomal development of carpal and tarsal bones
- Laxity of supporting structures
What is valgus?
Lateral deviation
What is varsus?
Medial deviation
What is the most common angular limb deformity?
Premature closure of the distal ulnar physis
What is osteopaenia?
Osteopaenia - loss of bone mass (remaining bone is adequately mineralised) - associated with - Ca+ and Cu+ def, GI disease, inactivity, glucocorticoids
Longitudinal growth is retarted with starvation/malnutriton. Growth resumes when diet is corrected. Growth arrest lines occur.
Name the condition below and state if it results in decreased quantity or quality of the bone:
Osteoporosis/Osteopaenia - reduced quantity but not quality
What are rickets and osteomalacia and what causes them?
Rickets and osteomalacia - defective bone and cartilage mineralisation - Osteomalacia causes bone softening and rickets cause softening of both bone and growth cartilage
Causes:
- Vitamin D deficiency
- Phosophorus deficiency
- Calcium deficiency (only in birds)
- Fluoride toxicity (rare)
What is the name of the condition shown below and what are the causes of it?
Fibrous osteodystrophy
Causes:
- Nurtitional secondary hyperparathyrodism - low calcium and high phosphorous
- Renal secondary hyperparathyroidism - failure to excrete P results in decreased Ca2+
- Primary hyperparathyrodism - adenomas
What is the name of the condition shown below?
Primary Osteosarcoma
What is the name of the conditon shown below?
Primary multiple myeloma
Name the condition that is shown below and state the cause of it:
Metastatic - Feline Lung Digit Syndrome
This is caused by a metastatic pulmonary carcinoma - cats - bronchiolar carcinoma is the most common
What is the name of the condition that is shown below and what is the cause?
Hypertrophic osteopathy - alterations to the blood flow leads to periosteal new bone formation
Causes: intrathoracic disease changes in vagovagal reflexes
What is the name of the condition shown below (new name + previous name) and what are some suspected causes of them?
Metaphyseal Osteopathy (previous called hypertrophic osteodystrophy) - septic or sterile - may need to do a biopsy and culture to determine cause
Young/adolescent large breed dogs:
- Bacterial infection likely - no organisms isolated
- Nutritional
What is the name of the condition that is shown below?
Panosteitis - Diaphysis - increased medullary bone densities
What is the name of the condition that is shown below?
Septic osteomyelitis - bacterial embolus lodges into growth plate
