MPL Facts
- Patella luxation is a muti-factorial problem of the hind limb, most commonly involving the tibial crest and trochlear groove.
- Patella luxation grade often progresses in the young animal due to cartilage wear and stretching of soft tissue structures.
- Treatment should be based on grade in the young patient and based on clinical signs in the older skeletally mature patient.
Assessing MPL Grades
- Medial patella luxation is a dynamic problem that should be assessed in the conscious, standing patient with the quadriceps mechanism under tension.
- It is important to assess the integrity of the anterior cruciate ligament as this is commonly involved in medial patella luxation cases.
- It is also important to assess the clinical signs associated with medial patella luxation.
Grade 0:
The patella cannot be luxated at any stifle position.
Grade1:
The patella can be luxated when the stifle is in full extension and the patella reduces immediately once pressure is released.
Grade 2:
The patella will spontaneously luxate but will return to be reduced in the trochlear groove. It can be pushed out more easily when the stifle is in extension and may remain out when the stifle is flexed but will spontaneously reduce when the stifle is cycled through its range of motion (ROM).
Grade 2.5:
The patella is generally reduced and spontaneously luxates, but more easily than grade 2.
Grade 3:
The patella is permanently luxated medially but can be manually reduced into the trochlear groove.
Grade 4:
The patella is permanently luxated and cannot be reduced into the trochlear groove.
What is MPL surgery?
Medial patella luxation surgery aims to realign the patella to sit in its groove. There are several techniques to achieve this. These include moving the anchor point of the patella, deepening the patella groove and de rotating the tibia. The techniques used are tailored to each case and may use one or a combination of several.What are the benefits of surgery?
- Reduction of acute lameness caused by patella luxation (dislocation)
- Increased exercise tolerance
- Reduced stifle (knee) and patella pain
- Reduced risk of cruciate damaged
- Slowing of degenerative changes associated with patella dislocation
- Improved lifelong knee function
What are the risks of surgery?
All surgery carries a risk of complications. It is important that you understand these risks. In certain cases these complications may require further surgical procedures to manage.
Surgical risks include:
- General anaesthesia
- Re-luxation (dislocation)
- Post operative infection
- Implant migration
- Bone fracture
What Aftercare is required:
Following surgery patients need 6-10 weeks of recovery and rehabilitation. This allows for healing of bone tissues and skin. It also minimises the chances of complications.
Aftercare involves:
- 6 weeks of strict cage rest
- Patient will need to be kept clean, dry, calm and away from other pets
- After 6 weeks of cage rest patients require controlled leash exercise which will gradually increase weekly
A more detailed aftercare plan will be supplied on patient discharge.