PAWSITIVE HAPPENINGS - February 2018 Veterinarian Newsletter

Posted February 27, 2018 in Articles
Clinic Updates
The Ins and Outs of patellar luxation:
We are making efforts to be feline friendly - using feliway diffusers constantly and having a designated feline exam room.  Our staff also go through fear-free training. One tip - if you are using Feliway diffusers in your hospital for constant use - they  need to be changed out every 6 months per manufacturer.
MVER has entered the quieter winter months as most of the snowbirds have flown south. However we did see three dogs in one week after they found their owner's marijuana brownies!
Our staff is happy to be volunteering with the Manchester Animal Shelter this year - both with their 5K fundraising, and their annual rabies clinic coming up in March.

Critical care, Cardiopulmonary medicine, Imaging:
Chris Rollings, DVM, DACVIM
Heather Jones DVM, MS, DACVIM (neuro)
Keith Montgomery DVM, DACVO
Kim Johnson DVM, DACVIM (onc)
Marlene Hauck DVM, PhD, DACVIM (onc)
Sean Kennedy DVM, DACVS
Stephanie Lister Grey DVM, MSc DACVS
April Chambers, DVM
Jessica Cioffi, DVM
Adrian Cloutier, DVM
Casey Cole, BVM
Gina Dinallo, DVM
Ashley Dunn, DVM
Ali Haghnazary, DVM 
Tricia Prine, DVM            
Amanda Profita, DVM
Timothy Hunt, DVM
Medial Patellar Luxation (MPL) is a common condition in small breed dogs and is becoming increasingly common in medium to large breed dogs as well. Although lateral patellar luxation (LPL) also occurs with some frequency in giant breed dogs the majority of patellar luxations encountered in clinical practice are MPL's. Studies have documented up to 95-98% of patellar luxations in small breed are medial and 81% and 83% of medium and large breed patellar luxations are also medial.
Patellar luxations are graded 1-4 based on clinical examination. Grade 1 patellar luxations can be manually luxated (usually only in extension) but do not luxate spontaneously. Clinical signs and radiographic bony abnormalities or signs of DJD are usually absent. Grade 2 luxations are characterized by spontaneous luxation that generally results in clinical signs of a seemingly non painful "skipping" lameness where the pet carries the leg and then after stretching resumes a normal gait with minimal to no lameness. Mild deformities such as internal tibial rotation and abduction of the hock are often present and these can progress to Grade 3 over time as erosion of trochlear and patellar cartilage occurs or secondary cranial cruciate rupture happens.
Grade 3 patellar luxations are permanently luxated but can be manually reduced. More significant bony abnormalities such as marked internal tibial rotation, a sigmoid deformity of the distal femur and proximal tibia and a shallow trochlear groove are typical. These are often bilateral and accompanied by a "crouched" gait where the dog walks with the legs semi flexed at the stifle and internally rotated.
Grade 4 patellar luxations are permanently luxated and cannot be manually reduced. The tibias may be internally rotated 60 to 90 degrees. Some affected animals, especially larger or overweight dogs may develop a crablike walking posture or refuse to walk. If not corrected early (during development) boney and soft tissue deformities can become severe and make surgery challenging.
Radiographs and clinical exam are useful to determine grade and to determine degree of degenerative joint disease, alignment abnormalities and to confirm the presence of a luxation. Orthogonal views of the stifle are adequate for lower grades and mild skeletal abnormalities. Skyline views, orthogonal views of both femur and tibia or computed tomography (CT) studies may be necessary to fully evaluate higher grades of patella luxation.
To cut or not to cut? Grade 1 patella luxations with no clinical signs can be treated conservatively. If lameness develops, especially in a young or growing animal, reevaluation is recommended. In cases of Grade 3 and 4 luxations surgical correction early in the disease is recommended to decrease progression of degenerative changes and in the case of animals with open growth plates the progression of skeletal deformities. In these cases (Grade 3 or higher patella luxation with significant growth potential left) a 2 stage repair is considered - first a soft tissue repair that spares the physes and limits progression of skeletal changes is done before skeletal maturity, if luxation recurs bone reconstruction techniques can be employed after skeletal maturity.
Grade 2 luxations that cause significant lameness should be surgically corrected as soon as identified. Significant lameness has been described as bouts that last 2-3 weeks or longer, or the three strikes recommendation of 3 or more periods of significant lameness in a short period (1 month or less). Grade 2 luxations that only cause mild and infrequent lameness with mild/non progressive arthritis can be treated conservatively with a plan to re-evaluate if lameness changes in character.

Sean Kennedy, DVM, DACVS

Opioid Overdose:
Many parts of the United States are currently experiencing an opioid crisis. According to the CDC, New Hampshire has been in the top five states for opioid overdose deaths in recent years. As the amount of opioids available in the general population increases, it also puts the pets that share those living spaces at risk of exposure and overdose.
Recently, pet dogs in British Columbia, Massachusetts, Maine, and New Hampshire have required treatment after exposure to legal and illegal opioid drugs - including our hospitals. Some of the exposures have happened in public places while the owner was walking their dog. Others have been to substances found inside the home. Opioid overdoses in drug detection dogs have also been reported nationwide, leading many police departments and organizations to carry the reversal drug and implement monitoring programs.
In every case the symptoms are similar to those in humans:
the dogs become weak, may stumble when they walk, and be poorly responsive to their owners. When medical attention is sought, victims of opioid overdose are often hypothermic (low body temperature) and bradycardic (low heart rate). In severe cases, dogs may have difficulty breathing.
Thankfully, naloxone, or Narcan, can be used to reverse opioid overdoses in dogs, as well as in humans. With immediate medical attention, administration of naloxone results in rapid reversal of the opioid overdose symptoms, often within five minutes. Occasionally additional doses are required, but if a patient receives naloxone soon after experiencing symptoms of overdose they should have a smooth recovery with no lasting negative effects.
Veterinarians' primary goal is treating the pet. They are not legally required to report pet overdoses and honesty regarding possible opioid exposure will speed treatment and potentially be life-saving. If your dog is experiencing sudden onset of weakness, especially if there is a possible exposure to legal or illegal opioids please seek veterinary attention immediately. 

Ashley Dunn, DVM