Case Study

CT – Bilateral Elbow Dysplasia in a young Male Bernese Mountain Dog

The patient has had an unusual gait from birth. The last few months this has worsened; he appears sore in all limbs, sometimes cries out on rising and favors the right front leg. Radiographs performed at rDVM who prescribed Rimadyl and made referral. The dog is very active but appears painful after play. Rimadyl is moderately effective – still lame. Also on Vitamin C, glucosamine, and a probiotic and Purina EN diet to control diarrhea. No history of seizures or allergies

Physical Exam: Weight: 68 pounds (8/6/2015); Pulse 150; Respiration Rate pant ; CRT 2 sec; MM Color P/M; Temperature 102.1. BAR today with a body condition score of 6/9. Eyes, ears, nose and throat appeared normal. The coat was healthy. On auscultation the heart and lungs WNL. Abdominal palpation WNL. Neurologically WNL. Pain Scale (Colorado 0-4) – 3/4. Gait was ambulatory, right fron leg weight-bearig lame. Pain on flexion of the left elbow; resistant to extension of left hip. Palpation of spine and neck WNL. CBC and chemistry WNL.

DX

The findings are compatible with bilateral elbow dysplasia.The right elbow presents severe and complex joint incongruity associated with cubital distraction due to short radius and medial coronoid pathology with fragmentation. The medial coronoid pathology is likely a function of the abnormal load pattern on the joint surfaces due to uneven longitudinal growth during skeletal maturation. Moderate osteoarthrosis is noted. Note that this is a very typical form of elbow dysplasia in this breed. The left elbow presents similar changes with significantly milder development as compared with the right side. There is a mild joint incongruity mainly represented by mild radioulnar step formation and medial coronoid pathology with a potential fissure line. Mild osteoarthrosis is noted.

Image Interpretation

CT of the thorax – Right elbow: There is a complex and severe joint incongruity with a short radius and
long ulna and a radioulnar step of 4.5 mm. The trochlear notch of the ulna is
asymmetric and flat when compared with the humeral trochlea. The radioulnar incisure
presents moderate asymmetry. There is an isolated demineralized and rounded bone
fragment cranial to the tip of the medial coronoid process measuring 3mm in diameter.
The periarticular margins present moderate bony modeling and mild osteophyte
formation. The medial coronoid process is sclerotic, irregular in outline and
heterogenous in opacity with loss of the trabecular bone pattern. There is moderate
trochlear notch sclerosis.
Left elbow: There is a mild joint incongruity with a short radius and long ulna and a
radioulnar step of 1.5 mm. The radioulnar incisure presents mild asymmetry. The
medial coronoid process is sclerotic, irregular in contour and heterogenous in opacity
with loss of the trabecular bone pattern. A potential fissure line was seen on the tip of
the medial coronoid process. The periarticular margins present mild bony modeling
and mild osteophyte formation. There is mild trochlear notch sclerosis.

Outcome

Depending on the clinical signs, arthroscopic (arthrotomic) revision of the right elbow
joint may be considered to remove the isolated bone fragment. Corrective osteotomy
techniques may be discussed to address the joint incongruity.
For the left elbow joint, surgical therapy should only be considered in case of clinical
signs.