Deformity secondary to bilateral incomplete ossification of the humeral condyle in a German Shorthaired Pointer dog

Summary

A five-month-old male, German Shorthaired Pointer dog was presented for severe, bilateral, thoracic-limb-lameness, with elbow swelling, pain, and crepitus. Radiography and computed tomography confirmed bilateral incomplete ossification of the humeral condyles (IOHC), with a non-displaced incomplete fracture of the left medial epicondylar crest and condylar deformity, characterised by enlargement of the trochleas with extension of the disto-medial aspect of the bone below the normal elbow joint level, and a deformed proximo-medial aspect of the ulna and radius. Transcondylar lag screws were placed bilaterally in an attempt to prevent fracture. Microscopic examination of biopsies, harvested from both humeral condyles, was supportive of IOHC. Six years after surgery, radiographs showed severe osteoarthritis and it appeared that fusion of the humeral condyles had not occurred. The dog followed an active life style until 10 years after surgery when the elbows showed almost no observable range-of-motion. However, discomfort was evident only after heavy exercise. Incomplete ossification of the humeral condyles may be associated with osteoarthritis, risk for non-union, implant failure, or secondary condylar fracture. This dog maintained good limb function despite these concerns, and despite bilateral humeral condylar deformity as well as development of severe osteoarthritis. This is the first report of a German Shorthaired Pointer dog with IOHC and the first histological description supportive of this condition in a five-month-old dog.

Keywords

Incomplete ossification of the humeral condyle - humeral condyle malformation - humeral condylar fracture - dog - German Shorthaired Pointer dog

• References

• 1 Marcellin-Little DJ, DeYoung DJ, Ferris KK. et al. Incomplete ossification of the humeral condyle in spaniels. Vet Surg 1994; 23: 475-487.
• 2 Meyer-Lindenberg A., Heinen V, Fehr M. Incomplete ossification of the humeral condyle as the cause of lameness in dogs. Vet Comp Orthop Traumatol 2002; 15: 187-194.
• 3 Gnudi G, Martini FM, Zanichelli S. et al. Incomplete humeral condylar fracture in two English pointer dogs. Vet Comp Orthop Traumatol 2005; 18: 243-245.
• 4 Charles EA, Ness MG, Yeadon R. Failure mode of transcondylar screws used for treatment of incomplete ossification of the humeral condyle in 5 dogs. Vet Surg 2009; 38: 185-91.
• 5 Fitzpatrick N, Smith TJ, O&Riordan J. et al. Treatment of incomplete ossification of the humeral condyle with autogenous bone grafting techniques. Vet Surg 2009; 38: 173-84.
• 6 Tomlinson JL. Fractures of the humerus. In: Slatter D., Editor. Textbook of Small Animal Surgery. 3^rded. Philadelphia: Saunders 2003: gs. 1914
• 7 Muir P, Johnson KA, Markel MD. Area moment of inertia for comparison of implant cross-sectional geometry and bending stiffness. Vet Comp Orthop Traumatol 1995; 08: 146-52.