NORMAL AND ABNORMAL BONE GROWTH IN THE DOG

GRISELDA F. HANLON DVM, M.S.

Welcome back to throwback Thursday. We’ve come a far way in diagnosing bone disease but it is interesting to see its physis ( 😉 ). Especially given the author of this OG paper, Bee Hanlon, the first female diplomate of the ACVR.

• Bee Hanlon was born and raised in Montana and graduated with a degree in entomology from Montana State College.

• She served in the US Navy working in the Malaria eradication program before entering veterinary college.

• In 1952, she was one of two women at the University of Minnesota to earn the Doctor of Veterinary Medicine degree.

• She later earned a Master of Science degree and became the first woman tenure track Assistant Professor at the University of Minnesota College of Veterinary Medicine.

• Bee became the first female Diplomate of the American College of Veterinary Radiology in 1969 and served as secretary of the ACVR.

• She was also a member of several professional societies and authored numerous articles for publication in journals including Veterinary Radiology & Ultrasound, Veterinary Pathology, and the Journal of the American Veterinary Medical Association.

• Bee retired from University service in 1985 but continued to receive accolades for her work, including being named Veterinarian of the Year in 2006 by the Minnesota Veterinary Medical Association for her work in founding and providing years of service to the Minnesota Veterinary Historical Museum.

Also, rachitis is rickets, as far as I can tell.

Overall Summary:

• The study focuses on the ossification time schedule in dogs to assist in radiologic interpretation of bone growth.

• It provides information on fusion rates, normal development, and various skeletal abnormalities.

• The data was collected from radiographs of normal dog skeletons at the University of Minnesota Veterinary Clinic.

Normal Development:

• Fusion of the acetabulum occurs between 4 and 6 months of age.

• Fusion of the femoral head, trochanter, and shaft occurs at 7 to 11 months of age.

• Fusion of the proximal tibia and fibular epiphyseal line occurs between 9 and 12 months of age.

Achondroplastic Dwarfism:

• Disturbance in endochondral bone formation resulting in shorter and wider bones than normal.

• Early closure of epiphyseal lines.

• Compressed vertebral bodies and irregular cartilaginous growth.

Stippled Epiphyses:

• Characterized by punctate areas of increased density in the epiphyses.

• Enlarged epiphyses and possible dwarfism.

• Centers may become smaller, fuse, or decrease in number.

Congenital Hip Dislocation:

• Bilateral hip dislocation observed in an 8-week-old German Shepherd puppy.

• Shallow acetabuli and abnormal tibial crest development.

• Abnormal rotation of the femur and presence of rachitis.

Osteochondrosis:

• Aseptic subchondral necrosis with separation of a bone fragment.

• Fragment becomes a "joint mouse" within the joint cavity.

• Occurs primarily in young animals before epiphyseal union.

• Causes include trauma, circulatory disturbance, vitamin and mineral deficiency, and infection.

Elbow Dysplasia:

• Ununited anconeal process and extra osseous body observed in a 6-month-old Basset Hound.

• Irregular and ununited process with osteoarthritic changes.

• Fusion rate of the affected elbow is faster than the unaffected elbow.

Osteochondritis Dissecans:

• Aseptic subchondral necrosis with separation of a small bone piece.

• Fragment becomes a "joint mouse" within the joint cavity.

• Detected in a 6.5-year-old Golden Retriever after injury.

Dyschondroplasia of the Radius and Ulna:

• Abnormal epiphyseal line and metaphyseal mushrooming observed in a 5-month-old Weimaraner.

• Premature closure of ulnar epiphysis causes radius elongation and bowing.

• Rachitis is evident.

Osteogenesis Imperfecta:

• Radiographic signs of demineralization, thin cortices, and fractures.

• Bands of increased density and lines of decreased density on long bone metaphyses.

• Suggestive of vitamin C and D deficiencies or possible heavy metal poisoning.

The View Box runs on AI and caffeine. If you want to buy me a coffee, feel free to upgrade. A coffee in my cafeteria is $2.07. If you want to buy me one coffee pick a yearly subscription. If you want to buy one a month, pick the monthly subscription.

There are no benefits to premium subscription.

Disclaimer: The summary generated in this email was created by an AI large language model. Therefore errors may occur. Reading the article is the best way to understand the scholarly work. The figure presented here remains the property of the publisher or author and subject to the applicable copyright agreement. It is reproduced here as an educational work. If you have any questions or concerns about the work presented here, reply to this email.