Patella Subluxation: Humans vs Dogs and rehab principles

Humans most commonly sublux their patella laterally whereas dogs more commonly sublux their patella medially; why and how can this be overcome?

It's simply the difference between being a bipedal and quadruped movement. A predisposing factor for patella subluxation is gluteal weakness. In humans with weak gluteals when they walk the hip will internally rotate and adduct therefore increasing lateral forces at the knee. This will be increased by the dominance of the lateral quadriceps muscles. Whereas, when a dog with weak gluteals walks their hip will externally rotate and abduct therefore increasing medial forces at the knee. This will be increased by the dominance of sartorius which contributes to hip flexion and has insertions around the medial aspect of the patella, therefore, increasing those medial forces even more.

So, what can be done about it?

• Address pain as this inhibits muscles though ice or laser.

• Strengthen the weak muscles in a pain free weight-bearing position, e.g. quarter squats rather than full squats.

• Use taping to improve muscle control and timing.

• Use a muscle stimulator to help with muscle recruitment of the quadriceps and gluteal muscles.

• Stretch iliopsoas as weakness, due to tightness, may be the reason that sartorius is dominant

• Ensure correct quads to hamstring ratio

• Address the imbalance between the quadriceps muscles

• Address any paw dysfunction that may be causing altered biomechanics

• Liaise closely with other members of the team looking after the dog's welfare to ensure that this is optimised.

Needless to say this post has excluded the osseous causes and surgical management options which remain the mainstay strategy to combat this pathology however, what if both strategies were performed in tandem? Would we see improved surgical results?