 Bubba
is a 2 year old small crossbreed who presented to us with a history of
lameness in the left forelimb for a period of 2 weeks. According
to the the owner, the lameness was intermittent and seemed about the
same intensity for the two week period. From the history, there
was no known incident of trauma to the leg or any excessive exercise,
which might have brought on the lameness.
On physical exam, the dog was painful in the region of the elbow.
At this point, our rule-outs included a joint injury such as a sprain or
strain of ligaments, or partial fracture of the bone. In
order to find out what was wrong, we sedated Bubba and took radiographs
of the limb. On inspection of the radiographs, we noted an area
below the elbow where the bone looks as if it is eaten away.
(click on images to enlarge)
note hole in bone
The possible causes of this type of lesion include: bone cyst,
bone tumor, or bone infection with either bacteria or fungus.
Typically, tumors tend to eat away the bone and have more dramatic
changes in the bone. Infections also tend to leave a bone which
looks more "angry" as the bone responds to the infection.
Because bone tumors often spread to the lungs (metastasize), we took
pre-operative radiographs of the lungs to look for tumors.
Fortunately, the lungs were normal and thus we moved on towards getting
our diagnosis.
In order to distinguish exactly what was going on in the leg, we took
Bubba to surgery and took a core biopsy out of the lesion. These
radiographs show the bone after the biopsy.
Bubba recovered from anesthesia without incident and we stabilized
the leg for 2 weeks with a splint to support the bone as it heals
from the surgery.
The biopsy specimen was sent to the lab for analysis. Typically
bone specimens take up to 1 week to be analyzed because the calcium has
to be leeched out of the bone so it can be sliced and prepared for the
pathologists. When we received the results, we were pleased and
somewhat surprised to find out that this was a benign lesion which
probably arose from prior trauma to the area. The trauma may have
injured the blood supply to that area of the bone and/or the bone cells
themselves so they were unable to create solid bone.
Removing the injured tissue has reduced the lameness and Bubba is
recovering nicely. |
