TL;DR: Clicking in a dog's knee often indicates a serious joint injury like a CCL tear and requires a veterinary examination within 24 to 48 hours to prevent long-term damage.
What does an audible clicking sound in my dog's knee mean?
An audible clicking or popping sound coming from a dog's knee, known as the stifle joint, often indicates a mechanical disruption within the joint. This sound is most frequently associated with a Cranial Cruciate Ligament (CCL) injury—the canine equivalent of an ACL tear. When the ligament is damaged, the joint becomes unstable, often causing the meniscus (a cartilage cushion) to get crushed or flipped, which creates that distinct clicking noise. Another common cause is a Luxating Patella, where the kneecap slides in and out of its natural groove.
Is my dog's clicking knee a veterinary emergency?
- The urgency level for a clicking knee is classified as Medium; while not typically life-threatening, it indicates structural instability and internal discomfort.
- You should aim to have your dog evaluated by a veterinarian within 24 to 48 hours.
- Immediate attention is required if your dog is completely non-weight-bearing.
- Prompt care is essential to avoid rapid onset of osteoarthritis or injury to the opposite leg due to overcompensation.
How do photos or videos of my dog's leg help with triage?
- A video captures specific gait abnormalities, such as a 'skip' or a 'toe-touch' lameness, which might disappear in the clinic due to adrenaline.
- Photos showing the way your dog sits or stands can highlight joint swelling or muscle wasting.
- Visual documentation allows the veterinary professional to prioritize your appointment based on the severity of the physical signs.
Clinical Context (Merck Veterinary Manual)
A clicking sound during locomotion or flexion and extension of the stifle joint may indicate a medial meniscal injury secondary to cranial cruciate ligament damage. Palpation of the stifle joint may also reveal patellar displacement, which can be graded based on severity of clinical signs and frequency of luxation. Radiography can be used to assess joint effusion, degenerative joint disease, and limb changes associated with patellar luxation. The severity of lameness and limb deformities varies with the grade of patellar luxation.
Chapter: Orthopedics
Source: The Merck Veterinary Manual, 11th Edition (Page 1199)