A luxating patella is a genetic condition where the dogs “kneecap” pops out of place. More often than not, the kneecap will generally pop back into place when the dog raises the leg out of pain. This is why dogs can seem fine, suddenly become in pain, then be fine again. The main cause of a luxating patella is the dog will have flat patella ridges contrary to larger ridges which would cause a groove in the leg (much like two mountains together). The kneecap moves in between those large ridges in a fluid motion, but if the ridges are flat, the kneecap may not have a path to follow, causing it to misalign. Misalignment is frequent when the dog is putting pressure on the leg such as running or jumping. Another cause of luxating patellae are hip issues such as hip dysplasia, which causes the kneecap to be pushed out of the groove, but is most commonly found in larger dogs rather than smaller dogs. Sometimes the kneecap coming out of place cannot be completely obvious, this is due to the cartilage surrounding the joint not having nerve endings, but over time this cartilage can be worn down or move causing the nerves in the bone connect with the nerves in the muscle or other bone ultimately creating pain.
Prevention (and general aftercare) of the animal can involve:
• Keeping the dog at a healthy weight as the heavier the dog is, the more weight it will put on its “knees”
• Maintaining good muscle tone, especially around the knees. This can help to create a barrier around the patella keeping it in line
• Use a good joint supplement, this can help prevent cartilage wear down and help promote joint fluid
• See a dog physiotherapist or chiropractor
Surgery is also an option for treating a luxating patella, surgery may involve cutting a deeper wedge in between the ridges, and/or tightening the joint capsule, the third way is by realigning the knee by moving it and pinning it in the new position. Tightening the joint capsule creates more tension in the joint. Surgery can be done on any grade of luxating patellae but is most commonly done on grade 3 to 4.
• PROM or ROM physiotherapy once directed by your veterinarian
• Limited exercise, to be on the safe side we generally crate for 8 weeks after surgery. Crating limits the area the dog can move, frequent short lead walks into the yard to toilet will be beneficial for both you and the dog.
• Inspect the surgical site daily. If the site looks as though its weeping, and inflamed, contact the veterinarian for advice. It's also beneficial to use an e-collar to prevent your dog from licking and chewing at his stitches, if the wound opens up it could lead to infection, infections not only sit on the surface but can move into the bone which is harder to treat.
• Stitches are generally removed 10-14 days after surgery, obviously depending on how the wound is healing.
By: Brooke Piwonski
Taken from The Advanced Certificate In Veterinary Nursing Assessment