Have you ever noticed when your dog’s hindlegs are lifted or when they are limping on one foot?
Patellar luxation or dislocation occurs when the kneecap is dislocated medially or laterally.
Medial dislocation is a common orthopedic condition found in small dogs.
Here, we would like to explain to you how surgeries for patellar luxations are conducted in our hospital.
[Common causes for patellar luxations]
- Congenital abnormalities in the knee joint and areas around the knee joint
- Acquired abnormalities caused by trauma etc.
[Different grades (or severity) of patellar luxation]
For patellar dislocations of grade III and above, orthopaedic surgeries are required.
In addition, although their condition might be grade II and below, surgeries are highly recommended should your dog experience pain or limping.
- Grade I: Dislocation caused when the patella is pushed by hand. The kneecap returns to its normal position spontaneously. No significant symptoms.
- Grade II: The kneecap occasionally rides out of its groove and can return to its normal position spontaneously. Symptoms such as limping or skipping can be observed.
- Grade III: The kneecap rides out of its groove most of the time but can be replaced in position through manipulation; although dislocation might occur again. Limping is evident, and deformation in the tip of the toes can be observed. Surgery is mandatory.
- Grade IV: The kneecap rides out of its groove all the time and cannot be manipulated back into place. Hind legs become lame; muscle atrophy and loss of muscle mass can be observed. Complications occurring after the snapping of the anterior cruciate ligament and the dislocation of the hip join (coxa) can be observed. Surgery is mandatory.
Recently, one of our puppy patients came to us, and it was diagnosed with grade III patellar dislocations for both legs. Although we manipulated and repositioned one of the legs a year before, another surgery was needed as constant lifting of the other leg was observed a year later.
[Our hospital’s surgery techniques]
- Confirmation of the trochlear groove.
The trochlear groove is shallow, hence it is easy for the knee to ride out of the normal position.
- Creating a trochlear groove
Since it is easy for the kneecap to ride out of the shallow trochlear groove, an artificial groove will be created.
- Moving of the shinbone
The muscles that connect from the thighs pass through the patellar and connect to the ridge of the tibia.
Partial osteotomy on the ridge of the tibia is performed where the position for the ridge is shifted to adjust the thigh muscles, patellar, trochlear groove, and the tibial ridge line.
The osteotomy is secured with K-wires (pins).
- Alignment and adjustments on the surrounding soft tissues.
To prevent the patellar from detaching easily, the medial fascia is released, and the outer fascia is sutured according to the muscle’s tension.
The wound is around 3-5cm long.
Bandages are used to secure the leg after the operation.
Bandages are to be removed after 5 days should the condition become stable.
Your dog is expected to be hospitalized for 5-7 days or more according to their condition.
- After discharging
After discharge, regular checkups are required to examine whether the pins are misaligned or whether your dog is able to move its legs properly. Normally, most of the dogs are able to move their feet well and move actively!
In our hospital, we have a specialized outpatient clinic for osteology!
During our regular consultation hours, you can consult the veterinarians on duty if your dogs are experiencing symptoms such as lifted paws, limping or deformed toes. Hence, please give us a call whenever you are ready to consult us about your dog’s situation.
Animal Hospital in Shibuya, Ebisu, and Daikanyama
HALU Animal Hospital
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