Page 241 - Canine Lameness

14.11 Panosteitis 213

14.11.2 Physical Exam
Panosteitis can affect all long bones, most commonly the bones of the elbow region (radius, ulna,
and humerus) followed by bones of the stifle region (Towle-Millard and Breur 2018). These long
bones should be carefully evaluated for pain upon deep palpation. When performing long bone
palpation, it is important to be aware of the local anatomy, since compression of the nerves may
result in a false-positive pain response. The disease starts in the location of the nutrient foramina;
however, the entire diaphysis and areas of the metaphysis can be affected. Physical exam should
also evaluate for any concomitant disease (such as ED).

14.11.3 Diagnostics

Radiographs are used most frequently to confirm the clinical suspicion of panosteitis. Radiographic
changes vary depending on the stages of the disease and are most visible in the location of the nutrient
foramina. During the early stages, a decreased radiodensity of the medullary cavity has been reported
(Towle-Millard and Breur 2018). However, the hallmark feature of panosteitis is an intramedullary
increase in radiodensity (Figure 14.10) since the early stages are frequently missed. Specific lesions
include opacities of the medullary canal (these can be well demarcated or diffuse, i.e. “medullary
blurring”), loss of normal trabecular pattern (i.e. “trabecular coarsening”), and changes to the endos-
teum (the layer that lines the medullary cavity, i.e. “endosteal roughening;” Stead et al. 1983). ELBOW REGION

(A)

(B)

(C) (D) (E) (F) (G)

Figure 14.10 Panosteitis: (A, F, G) normal radiographs for comparison; (B–E) radiographs consistent with
panosteitis illustrating the variable radiographic appearance of this disease: (B) increased intramedullary
opacity and loss of trabecular pattern (black arrow); (C) well-demarcated intramedullary opacity (white
arrow); and (D, E) endosteal roughening and diffuse intramedullary opacities (white arrows).