310 Canine Sports Medicine and Rehabilitation
theories have been investigated including
defective osteochondral ossification, abnormal
ities of the trabecular bone of the coronoid pro
cess, and biomechanical influences including
radioulnar incongruity (Trostel et al., 2003a;
Danielson et al., 2006; Temwichitr et al., 2010). A
wide spectrum of FCP can be seen ranging from
large, discrete osteochondral fragments to small
cartilage fissures that are only appreciated
with advanced imaging or histopathology
(Danielson et al., 2006; Fitzpatrick & Yeadon,
2009). Regardless of the underlying etiology,
FCP inevitably results in the development and
progression of osteoarthritis, particularly
within the medial compartment or humeroul
nar articulation of the elbow (Clements et al.,
2006; Fitzpatrick & Yeadon, 2009).
Diagnosis
Dogs commonly present at 4–12 months of age,
although some may not show clinical signs
until later in life after degenerative joint disease
becomes severe (Trostel et al., 2003a; Fitzpatrick
& Yeadon, 2009). Juvenile dogs with FCP typi
cally have an insidious onset of mild to severe
weight‐bearing lameness that is aggravated by
activity. Often, they will shift weight to the
unaffected or less severely affected limb, with
the affected limb held with the elbow adducted
and foot abducted or externally rotated. This is
commonly confused with a valgus limb deform
ity (Trostel et al., 2003a). There may be muscle
atrophy, and some patients may have the
appearance of overdeveloped hindquarters due
to increased weight bearing through the pelvic
limbs. Joint effusion is rarely appreciated with
FCP or osteochondrosis. Pain can be elicited
with supination of the antebrachium with the
elbow in flexion or extension (Trostel et al.,
2003a; Fitzpatrick & Yeadon, 2009). Deep palpa
tion over the biceps brachii insertion near the
medial coronoid commonly results in a pain
response (Fitzpatrick & Yeadon, 2009). As
degenerative changes of the joint develop,
fibrous thickening of the medial compartment,
crepitus, and loss of range of motion can be
appreciated. These clinical findings are identi
cal to those seen with osteochondrosis, and
clinical exam alone is unlikely to differentiate
the two (Trostel et al., 2003a; Fitzpatrick &
Yeadon, 2009).
A series of elbow radiographs is recom
mended initially. However, discrete visualiza
tion of a fragmented coronoid process is not
possible (Moores et al., 2008; Cook & Cook,
2009a; Punke et al., 2009). Rather, secondary
signs such as sclerosis of the subchondral bone
at the semilunar notch and enthesiophyte for
mation on the dorsal anconeal process are seen
(Danielson et al., 2006; Cook & Cook, 2009a).
Studies have shown radiographs to be highly
insensitive to diagnosing FCP and, therefore,
advanced imaging should be recommended
(Danielson et al., 2006; Moores et al., 2008; Cook
& Cook, 2009a; Punke et al., 2009).
CT is very effective for diagnosing and char
acterizing FCP (as well as osteochondrosis) but
is not capable of evaluating the articular carti
lage (Moores et al., 2008; Cook & Cook, 2009a).
Arthroscopy is recommended alone or in com
bination with CT to assess the integrity of the
articular cartilage as well as radioulnar congru
ity (Moores et al., 2008; Punke et al., 2009). MRI
can be used to evaluate the elbow and is more
sensitive than CT for evaluating the surround
ing soft tissues, subchondral and medullary
bone, cartilage, and bone–cartilage interface
(Cook & Cook, 2009a; Baeumlin et al., 2010).Treatment
In one author’s (SC) opinion, arthroscopic treat
ment should be considered as soon as the con
dition is diagnosed. If there are questions
regarding a definitive diagnosis, arthroscopy
would allow for confirmation of the condition
while at the same time providing treatment.
Depending on the severity of disease, arthro
scopic treatments typically include fragment
removal (taking the “pebble out of the shoe”;
Figure 12.20); subtotal coronoidectomy (remov
ing unhealthy coronoid tissue); abrasion arthro
plasty (stimulating the subchondral bed for
the formation of fibrocartilage); resurfacing
(shaving down areas that are in conflict or
abnormally communicating); and microfrac
ture or micropicking (to open channels into
the subchondral bone to assist in fibrocartilage
formation). Even older patients in which osteo
arthritic progression is noted can benefit from
arthroscopic treatment before they enter into
a formal rehabilitation program. With the
advancement of arthroscopic instrumentation,