A Luxating patella is a term to describe a dog with a patella which dislocates from its normal position in the trochlear groove. It is common (1 in 2 cases) for a dog to be affected in both hindlimbs, however the severity of the condition in each limb may differ. 

There are four grades of luxating patella which are as follows. 

• “Grade 1: A knee cap that can be luxating with manual pressure but is otherwise is within the groove.
• Grade 2: The knee cap spontaneously luxates, is typically associated with a skipping lameness when the knee cap moves.
• Grade 3: The knee cap is permanently luxated but can be manually replaced in the groove.
• Grade 4: The knee cap is permanently luxated and cannot be manually replaced in the groove.” (Fitzpatrick Referrals,2023a) 

It commonly affects smaller dogs such as Yorkshire Terriers, Chihuahuas, French Bulldogs and Cavalier King Charles Spaniels but larger dogs can also be affected. 
 

Cause and progression 

Genetics play a huge role in the cause of a luxating patella, and it can be the consequence of breeding dogs to a breed standard which prefers a bow-legged conformation. Other causes include trauma or repetitive, day to day activities which see a great degree of wear and tear placed on the joint such as slipping on laminate flooring. 

Where genetics are the main cause, the dog will begin to develop abnormalities in the bone and muscles of their hindlimbs early in life such as the femur, tibia and fibula growing in a deformed manner. This then continues to exacerbate the condition. 

Regardless of cause as the patella continues to displace over time it can wear down the cartilage in the joint which can then trigger osteoarthritis. The increasing stress of the structures around the stifle make it more likely that a dog will also experience a cruciate ligament tear. 
 

Onset & symptoms 

The condition will progress over time through the four grades if there is no intervention. Dependent on how often the patella luxates and the stresses the joint is put under will depend on the speed that the condition progresses. Surgery is not advised to correct a grade I luxating patella, this should instead be managed through a multi-modal rehabilitation program, however surgery is advised for Grades II-IV. 

A classic symptom of a luxating patella is a skipping gait, where the dog will hop for several strides before returning to a normal gait. Other symptoms an owner may notice include a constant lameness of the hindlimbs, the dog may present with pain, an audible clicking of the knee as it displaces or moves over the groove may be heard or the dog may be unable to fully straighten one or both of its hindlimbs. 

How massage can help

Massage can be extremely beneficial for grade I luxating patellae, and with management this may mean the dog does not need surgery (subject to the dog’s veterinarian re-assessing the condition in conjunction with the massage therapist’s clinical reports.) 

With regards to grades II – IV, massage can help to relieve overcompensating muscles of the hindlimb, hip and spine, and as such reduce the pain from these. It can also be beneficial post-surgery to help improve blood circulation and the movement of lymph around the body, whilst the dog is less mobile. 

Information sourced from

Fitzpatrick Referrals (2023) Patellar luxation, Fitzpatrick Referrals. Available at: https://www.fitzpatrickreferrals.co.uk/orthopaedic/patellar-luxation/ 

Lenton, N. (2018) Cruciate ligament, Canine Massage Therapy Centre. Available at: https://www.k9-massage.co.uk/conditions/orthopaedic/cruciate-ligament/ 

The Kennel Club (2023) Patella luxation in dogs, The Kennel Club. Available at: https://www.thekennelclub.org.uk/health-and-dog-care/health/health-and-care/a-z-of-health-and-care-issues/patella-luxation-in-dogs/ 

Weir, M., Hunter, T. and Ward, E. (2023) Luxating patella in dogs: VCA Animal Hospitals, Vca. Available at: https://vcahospitals.com/know-your-pet/luxating-patella-in-dogs 

Baker, J. (2020) Luxating patella - how do you rate your dogs skipping and hopping?, Canine Massage Guild. Available at: https://www.k9-massageguild.co.uk/luxating-patella-how-do-you-rate-your-dogs-skipping-and-hopping/