I found a in depth paper on this. It appears that surgery is pretty succesful, and I am not sure it says to wait for surgery, it sounds like earlier is better, but I only skimmed. I am going to attach it. It sounds like if you want to keep the cat, the surgery is essential. It also discussed antiinflammatory drugs for it, so maybe your doc is not up to date on pain control.
IT is a tough choice. If it is a onetime surgery and the prognosis is good, I would go for it, if I could afford it. I know taking the cat back is difficult. I had thet choice when I adopted Spike, who was half dead from everything, the vet was kind of encouraging me to take him back cause he was so sick, but he said he could be healthy after treatment, so I treated and now he is beautiful.
It depends on what you are willing to invest. I know some people will spend enormous amounts of money, but I think there are limits, as cold hearted as that sounds. If I were wealthy, it wouldn't matter, but I am not. You have to determine what your limit is. But a good prognosis, sounds like a good investment.Introduction
Patellar luxation is an intermittent or permanent
fixing of the patella by changing the position towards the
lateral, medial or upper portion of the femoral trochlea.
This disorder is most commonly seen in horses, cattle,
oxen and dogs (1-3) and rarely in cats (4-8).
Patellar luxation may be either congenital or acquired.
Congenital patellar luxation may happen due to various
congenital malformations of coxa-vara, coxa-valga, genuvara,
lateral torsion or bending of the distal third of the
femur, medial dislocation of the quadriceps muscle group,
dysplasia of the femoral epiphysis, rotational instability of
the stifle joint, medial rotation of the tibia, medial
dislocation of the tibial tuberosity, shallowness of the
femoral trochlea, false trochlea formation on the medial
condyle of the femur and DJD (2,5,8-13). On the other
hand, acquired patellar luxations are caused by indirect or
direct trauma (1,2). Indirectly, it is caused by sudden
inward rotation of the tibia while the stifle joint is
extended (jumping or falling from a height). Direct
trauma occurs by following fractures of the joint or areas
close to the joint (2). In one study, Davis and Gill (4)
encountered patellar luxation of cats in only 6 cases over
a period of 11 years. Patellar luxation may occur in
Devon-Rex, British Shorthaired and Siamese cats
(4,5,7,14). While Fleknell (6) determined congenital
patellar luxation in 29 (90.6%) of the 32 Devon-Rex cats,
they observed patellar luxation in only 10 (10.3%) of the
97 cats belonging to other breeds. Davis and Gill (4) have
stressed that the possibility of congenital patellar luxation
formation by as a result of mating with British
Turk J Vet Anim Sci
29 (2005) 279-283
A Retrospective Study: Evaluation of Patellar Luxation Cases in Cats
Department of Surgery, Faculty of Veterinary Medicine, Ãœstanbul University, AvcÃlar 34840, Ãœstanbul - TURKEY
Abstract: Patellar luxation is an orthopedic disorder seen rarely in cats. In this study, patellar luxation was encountered in 8 of 7744
cats brought to the Department of Surgery of Faculty of Veterinary Medicine of Ãœstanbul University between the years of 1995-
2001. The rate of patellar luxation was 0.10% of feline cases. The patellar luxation incidence in 5145 orthopedic lesions in cats was
0.15%. Clinical symptoms such as difficulty in walking, running with a hop and abnormal stance in the hindlimb were seen in patients
diagnosed using skyline radiography technique. The aim of the present study was the clinical diagnosis and early treatment of this
low incidence disease of cats. Treatment procedures have been determined in these early-diagnosed cases according to the degree
of the disease. Two of these cases were treated conservatively and 6 operatively. It was concluded that capsuloraphy combined with
sulcoplasty increased the success rate.
Key Words: Cat, patellar luxation
Bir Retrospektif ‚alÃÃŸma: Kedilerde Patella Luksasyonu OlgularÃnÃn DeÃ›erlendirilmesi
…zet: Patella Luksasyonu kedilerde olduka ender rastlanÃlan bir ortopedik bozukluktur. Bu alÃÃŸmada 1995-2001 yÃllarÃ arasÃnda
Ãœstanbul †niversitesi Veteriner FakŸltesi Cerrahi Anabilim DalÃ kliniÃ›ine getirilen toplam 7744 kediden 8Ã•inde patella luksasyonuna
rastlanÃldÃ. Bu patella luksasyonuna oranÃ kedilerde % 0,10 gibi olduka dŸÃŸŸk bir deÃ›er olarak saptandÃ. AynÃ sŸrete 5145 kedide
rastlanan ortopedik lezyon arasÃndaki patella luksasyonu insidensi % 0,15 olarak belirlendi. YŸrŸrken zorlanma zÃplayarak koÃŸma ve
arka ayaklarda anormal basÃÃŸ pozisyonu gibi klinik semptomlar gšsteren hastalarda tanÃya ulaÃŸmak iin skyline radyografi
gšrŸntŸleme tekniÃ›i de kullanÃldÃ. Bu alÃÃŸmanÃn amacÃ, kedilerde insidansÃ ok dŸÃŸŸk olan hastalÃÃ›Ãn klinik muayenede teÃŸhisi ve erken
saÃ›ÃltÃmÃdÃr. Erken dšnemde teÃŸhis edilen olgularÃn tedavilerinde hastalÃk derecesine gore saÃ›ÃltÃm yšntemi belirlendi. Bu olgularÃn
2Ã•si konservatif 6Ã•sÃ operatif olarak saÃ›altÃldÃ. Sulkoplasti ile birlikte kapsulorafi uygulamasÃnÃn, baÃŸarÃ ÃŸansÃnÃ arttÃrdÃÃ›Ã sonucuna
Anahtar SšzcŸkler: Kedi, patella luksasyonu
Shorthaired cats is reasonably low. Houlton and Meynink
(15) have reported that patellar luxation in cats usually
originate from trauma. Patellar luxations in cats mostly
occur medialis and may be either unilateral or bilateral
(4,6,7,15,16). Lameness may not occur. Abnormal
hindlimb stances, kneeling stance and lack of confidence
can be observed (4,6). It has also been stressed that the
stifle joint may become locked in some cats when walking
(17). Definitive diagnosis is based upon radiographic
evaluation. The patella can be seen in position to move
away from its normal location within the trochlear groove
in antero-posterior and medio-lateral radiographs. The
diagnosis is confirmed by the use of skyline imaging
technique (Figure 1), which is specific for patellar
luxations, taken with the joint in full flexion (18).
Avascular necrosis of the femoral head, coxo-femoral
luxation and joint distortions must be eliminated in
differential diagnosis (8,9,11). Prognosis is good for
stationary dislocations. In habitual dislocations,
reoccurrence may occur in the post-operative period (1).
Narrowing of the joint capsule (capsuloraphy),
sulcoplasty in young animals (trochleoplasty), fixation
from the fabella to the patellar ligament (patelloplasty),
wedge osteotomy in adult small animals (wedge
resection), transposition of the tibial tuberosity is used
individually or in combination (2,3,5,8-11,13,17,19).
The best surgical technique in cats is either sulcoplasty or
tibial tuberosity transpositions or the combination of
these (19). Ruptures of the cranial cruciate ligament and
degenerative changes on joint surface of femoral condyles
of tibia may occur in animals that have not undergone
surgery (2,8,10,15,17). The aim of the present study
was to discuss the patella luxation in cats over 7 years and
to reflect on it.
Materials and Methods
Eight cats with a complaint of inability to use their
hindlimb or difficulty in walking were brought to the
University of Istanbul Veterinary Medicine Department of
Surgery between the years of 1995-2001. Clinical and
radiological examinations confirmed patellar luxation. Of
the cases, 2 were treated conservatively and 6
operatively. The first of the two cases treated
conservatively (case no. 5) had congenital and permanent
bilateral luxation with lateral torsion and bending of the
distal third of the femur together with medial rotation of
the tibia. The patella in the second case treated
conservatively (case no. 6) had intermittent and bilateral
luxation along with subluxation of the coxo-femoral joint.
Analgesic and non-steroid anti-inflammatory drug
carprofen (RimadylÂ¨ 20 mg Tb) was administered orally
at a dose of 2 mg/kg in conservatively treated cats. Six
cases were treated surgically. While capsuloraphy was
performed in only one case (case no. 1), sulcoplasty
together with capsuloraphy was carried out in the
remaining five cases (cases no. 2, 3, 4, 7 and 8).
Following fixation, a bandage was not used during the
postoperative period but the owners were advised to
restrict the animalÃ•s movements.
Patellar luxation was diagnosed in only 8 cats out of
7744 with various complaints brought to the University
of Istanbul, Veterinary Medicine, and Department of
Surgery after clinical and radiological examination
between the years 1995-2001. (Table 1). The rate of
patellar luxation in cats was 0.10%.
The rate of patellar luxation was 0.15% among the
orthopedic disorders (5145) in cats. All the cats except
one (case no. 6) were under the age of 2. Three cats were
female and the rest of them were male. Complaints
consisted of difficulty in walking (cases no. 5, 6, 7 and 8)
or lameness (cases no. 1, 2, 3 and 4). Three of the
patients (cases no. 1, 3 and 8) had left patellar luxation
(LPL), two (cases no. 2 and 4) had right patellar luxation
(RPL) and three (cases no. 5, 6 and 7) had bilateral
A Retrospective Study: Evaluation of Patellar Luxation Cases in Cats
Figure 1. Skyline imaging technique
patellar luxation (BPL). One of the cases diagnosed with
BPL (case no. 7) also had hip dysplasia (HD). [B(PL+HD)].
The other case (case no. 6) had coxo-femoral subluxation.
Of the cases, 4 were intermittent and 4 permanent. Three
cases (cases no. 2, 3 and 5) were decided to have
occurred congenitally. In case no. 5, which was treated
conservatively, bilateral locking of the stifle occurred 6
months later and euthanasia was carried out upon the
ownerÃ•s request (Figure 2). The other case (case no. 6)
had periodical check-ups and following one year the
owner reported that the cat did not have much difficulty
in walking. Complete recovery was achieved in all of the
cats treated surgically (cases no. 1, 2, 3, 4, 7 and 8).
There were no post-operative complications in any of the
cases (Figures 3-7).
Table 1. Evaluation of patellar luxation in cats.
Case Breed Age (M) Gender History Side Grade Diagnosis Treatment Follow-up
1 SHD 24 F stretching left leg L I LPL C 3 months later (+)
backwards from (medial)
time to time
2 SHD 4 M sudden lameness R P RPL (medial) S + C 4 months later (+)
in right leg Congenital
3 SHD 7 M lameness in left leg L P LPL (medial) S + C 6 months later (+)
4 LHD 7 M stretching left leg R I RPL (medial) S + C 3 months later (+)
time to time
5 LHD 7 F difficulty in walking R-L P BPL (medial) Co 6 months later (-)
6 SHD 144 F difficulty in walking R-L I BPL + CFS (medial) Co 3 months later (Â±)
7 LHD 8 M difficulty in walking R-L P B (PL + HD) (medial) S + C 3 months later (+)
8 LHD 8 M difficulty in walking L I LPL (medial) S + C 4 months later (+)
SHD: Short-haired domestic, LHD: Long-haired domestic, M: Month, I: Intermittent, P: Permanent, LPL: Left patella luxation, RLP: Right patella luxation,
BPL: Bilateral patellar luxation, HD: Hip dysplasia, CFS: Coxa-femoral subluxation, C: Capsuloraphy, S: Sulcoplasty, Co: Conservative, PL: Patella
luxation, (+): Clinically and radiologically no problems, (-): Euthanasia, (Â±): Radiologically bad, clinically no problem.
Figure 2. Case no. 5, 6 month follow up Figure 3. Case no. 4 (Pre-operative)
Patellar luxation cases are very rare in cats.
Occurrence of only 8 cases (a rate of 0.10%) in this study
confirms the published reports (3-6). A rate of 0.15%
among all the orthopedic disorders in cats is a rather low
incidence compared to other diseases in cats. All the cats
were under the age of two except one, which was 12
years old, which is in agreement with the literature (15).
The patellar luxation in the 12-year-old cat occurred
following subluxation of the femoral head. Patellar
luxations have been reported to be either congenital or
acquired (2,5,9,11). In this study, congenital patellar
luxation was observed in 3 cases. Lateral torsion of the
distal of the femur in one in these cases (case no. 5)
confirms the literature stating that dysplasia of the
femoral epiphysis and medial dislocation of the tibial
tuberosity is a congenitally originating etiological factor
(8,9,11,13). Acquired patellar luxations in cats are
reported to have a traumatic origin (15). In this study,
only 1 of the 5 cases of acquired origin was suspected to
have occurred due to trauma. The presence of obvious
capsule laxity in other 4 cases suggested that the luxation
A Retrospective Study: Evaluation of Patellar Luxation Cases in Cats
Figure 4. Case no. 4 (Post-operative)
Figure 5. Case no. 7 (Pre-operative)
Figure 6. Case no. 7 (Post-operative right stifle joint)
Figure 7. Case no. 7 (Post-operative-bilateral luxations)
had occurred gradually. Hereditary patellar luxation can
occur as a breed disposition in Devon-Rex, British
Shorthaired and Siamese cats (4-7). It was revealed that
the congenital patellar luxations occurring in 3 cases with
different breed characteristics were not present in the
littermates, which had the same genotype. This finding is
parallel to the conclusions of Davis and Gill (4), who
suggest that patellar luxations in cats are not hereditary.
Radiographic examination is used to determine the
position of the patella within the trochlear groove of the
femur and the degree of trochlear depth (1,2,5,9,10). It
is recommended that the skyline imaging technique be
used to confirm radiological diagnosis (18). Radiographs
taken by skyline technique were much better at
confirming the diagnosis and determining the depth of
the trochlear groove compared to the antero-posterior
position. The prognosis of patellar luxations in cats has
been reported to be good (1,19). Similar to our findings
Houlton and Meynink (15) have reported that treatment
of patellar luxation in cats is either conservative or
operative. Considering the fact that the desired positive
result from the conservatively treated 2 cases has not
been achieved, we do not agree with the researchers
claiming conservative treatment could be a preferable
method. Operatively, different techniques described
earlier have been used (2,5,8-11). Koch and Montavon
(19) have recommended sulcoplasty and tibial tuberosity
transposition or the combination of these methods. In
this study, while capsuloraphy was carried out in only one
case (case no. 1), sulcoplasty together with capsuloraphy
was applied to the remaining 5 cases. Successful surgical
results were achieved in all cases due to less traumatizing
techniques without an osteotomy.
It was concluded that skyline-imaging technique along
with clinical examination must be used for the diagnosis
and of patellar luxation and combining the sulcoplasty and
capsuloraphy techniques can increase the success rate of
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