The patella is a small bone at the front of the knee (the knee-cap). It is positioned between the quadriceps muscle and a tendon that attaches to the shin bone. The patella glides in a groove at the end of the thigh bone as the knee flexes and extends.
Occasionally the patella slips out of the groove. This is called luxation or dislocation,. Most commonly the luxation is towards the inside (medial aspect) of the knee, however, it can also dislocate towards the outside (lateral aspect) of the joint.
The patella luxates because it (and the quadriceps mechanism in general) is not aligned properly with the underlying groove. The resultant abnormal tracking or movement of the patella causes it to slip out of the groove.
Patellar luxation is associated with the development of osteoarthritis within the knee . This occurs in every case. Osteoarthritis tends to be a progressive disorder and it is doubtful whether treatment of the patellar luxation reduces or stops this progression.
Occasionally luxation of the patella is associated with rupture of the cranial cruciate ligament in the knee. This may be due to chance or possibly due to abnormal forces on the joint that weaken the ligament.
Affected dogs may show signs of:
Examination may reveal muscle wastage, especially over the front of the thigh, although this is often minimal.
Manipulation of the knee may enable the detection of instability of the patella as it slips in and out of the groove. In some dogs the patella is permanently out of the groove.
The severity of the luxation is graded from 1 to 4, with a grade 4 being the most severe.
X-rays provide additional information, especially regarding the presence and severity of osteoarthritis.
Some dogs with patellar luxation can be managed satisfactorily without the need for surgery. The smaller the dog and the milder the grade of luxation (e.g. grade 1 out of 4), the more likely it is that this approach will be successful.
Exercise may need to be restricted. Hydrotherapy is often beneficial. Dogs that are overweight benefit from being placed on a diet. Regular monitoring of weight may be necessary.
Many dogs with patellar luxation benefit from surgery. The key types of surgery are:
Exercise following femoral osteotomy surgery must be restricted until the cut bone has healed. Exercise must be on a lead or harness to prevent strenuous activity. Jumping and climbing should be avoided. X-rays are necessary between six and eight weeks following surgery to ensure bone healing is progressing without complication. Exercise may then be gradually increased in a controlled manner as guided by a physiotherapist and Hydrotherapy is often recommended.
Rehabilitation is a process which aims to maximise patient mobility and wellbeing, returning them to their usual way of life following illness, injury or surgery. We restore pets to normal function (or as close as is possible), efficiently and safely using a wide variety of physiotherapeutic techniques.
Injury and even surgery can disrupt the body’s equilibrium in all sorts of direct and indirect ways. Even a pet’s own protective responses such as the inflammatory process can overwhelm and inhibit healing so one objective of rehabilitation is to reduce this level of inflammation. During rehabilitation, we also aim to boost the circulatory system, improve muscle function, increase range of motion within joints, and stimulate innate pain-relieving mechanisms.
With a committed and planned rehabilitation programme, pets can recover more quickly, realise better outcomes and avoid much pain and discomfort.
The best rehabilitation programmes consider the whole pet, not just the area of injury; we target and improve multiple systems throughout the body without forgetting the invaluable healing effects of boosting mental wellbeing too. From the wound healing properties of laser treatment, and the muscle strengthening of hydrotherapy, to the circulation boosting effects of massage, we will devise a rehabilitation programme to match a pet’s specific requirements.
The content on this page is for advice and information only and does not represent veterinary guidance or direction. Please always consult a veterinary surgeon if you are worries about your dog.