Case Study: Limb Spare

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Akiko is an almost 8 year old spayed female mixed breed dog that presented to VSH North County for evaluation of wounds suffered from a dog bite.

firstopenpaw

I evaluated Akiko the morning after she arrived through our ER. Akiko had a severe wound on the distal aspect of the left thoracic limb. The wound encompassed the entire dorsal metacarpal surface with exposure of the extensor tendons. There was a comminuted grade 3 open fracture of the 5th metacarpal bone. The wound extended to just proximal to the metacarpal pad. There was no overt instability of the carpus and manus as a whole. A dorsopalmar radiograph was obtained and delineated the MC5 fracture but no other overt bony injuries. There was conscious sensation in the digits.

I met with Akiko’s owners and discussed treatment options. They were interested in salvaging her limb if at all possible. The challenges associated with ensuring tissue health followed by obtaining closure of the wound were discussed, but limb salvage was considered feasible since enough of the weight bearing portion of the paw was not affected. We discussed that there would be an initial phase of open wound management to allow granulation tissue formation (ensuring tissue health and greatly reducing the risk of infection), followed by reconstructive procedure(s) to achieve a functional result, as the defect was considered too large to allow second intention healing and in a location that primary closure was not possible.

openpaw

The wound was managed with daily dry-to-dry bandages until a healthy granulation bed covered the majority of the wound. The dry-to-dry bandages allowed sequential mechanical debridement of the effusive wound. 9 days following initial presentation, Akiko was taken to surgery and a phalangeal fillet procedure performed. The bones of the fractured 5th metatarsal were removed along with the phalanges, but all associated skin and subcutaneous tissue from the digit was left intact. The resulting skin flap was rotated into the wound and sutured either to the adjacent skin or to the granulation bed. The digital pad was included as part of the flap to increase coverage. This procedure resulted in approximately 65% closure of the wound.  This procedure was chosen because the high-grade open fracture was at risk for infection and/or delayed healing, and because loss of the digit would not preclude weight bearing. The phalangeal fillet provides a durable skin flap that is not prone to vascular compromise.

healedpaw

The flap and remaining wound continued to be managed with a bandage using a non-adherent primary layer. At two weeks post-operatively, the flap demonstrated 100% survival including the digital pad. The remainder of the wound continued to contract and epithelialize, so no additional procedures (such as a free skin graft) were elected. The bandage was removed at approximately 5 weeks after presentation, at which time there was a slightly exuberant ~2cm granulation bed remaining on the dorsum of the paw adjacent to the transposed digital pad.

At approximately 6 weeks after initial presentation, the wound was completely closed with the exception of a ~1cm scab in the same dorsal location. Akiko demonstrated a grade 1/4 left thoracic limb lameness. The owners were instructed to wean Akiko off of her e-collar if and when she does not resort to self-trauma. No further intervention is planned.

Sun Protection for Your Pets

Our pets are just as vulnerable to sunlight-induced skin disease as we are. Some pets worship the sun as much as their beach-going humans do. In people, addiction to tanning is associated with the production of endorphins produced as part of the skin’s immune response to light exposure. Similar sun-seeking behavior can happen in pets as well. Although hair protects many animals from sunlight, not all parts of the body are covered with sufficient hair to shield the underlying skin from solar damage.

The armpits, abdomen, skin in front of the ears, nose and muzzle are vulnerable in all pets; short-coated breeds and lighter pigmented individuals are particularly at risk. Even indoor-only pets can have problems with too much sun.  Although double-paned and newer glass windows can prevent most harmful effects of the sun, older glass windows do not block all types of potentially damaging solar radiation.

Too much sun can cause problems ranging from burns to cancer. Dogs and cats can get precancerous lesions called actinic keratoses, which can then progress to skin cancers such as squamous cell or basal cell carcinoma. Some dogs can develop tumors of the blood vessels called hemangiomas.

The best protection strategy in humans and animals is avoidance of the sun, particularly when radiation levels are the highest, between 10 AM and 4 PM.  Early morning and evening are the safest times for long walks or outdoor play.  A penned enclosure with shade cloth can be effective in treeless yards.

Some companies make “sunwear” for dogs, designed for solar protection. Human clothing can be adapted for our pets as well, although few dogs or cats tolerate hats.

Sunscreen use in humans has increased along with awareness of the damaging effects of too much sun. However, sunscreen is typically not applied appropriately or at high enough frequency to be effective.  The use of sunscreens may impart a false sense of security, leading people to spend more time in the sun at the most dangerous times of the day.  Veterinary sunscreens are available; human zinc-free sunscreens designed for use in infants can be alternative.

What Is The Spleen?

What is the spleen?

The spleen is a tongue shaped organ of the abdomen that acts as a reservoir for blood as well as filters the circulating blood.  It removes and recycles old red blood cells and attacks any blood borne pathogens like bacteria and parasites commonly associated with tick borne diseases via its large volume of lymphoid tissue (immune system).

Canine and feline spleens may distend and contract to help increase circulating blood volume and this can be influenced by anesthetic medications.  Spleens can be surgically removed without significant compromise to our pets’ long term health.

When does an enlarged spleen need to be further evaluated?

Patients may be presented to a veterinarian for a variety of non-specific signs of illness resulting from an enlarged spleen or splenic mass.  Vomiting, inappetence, weight loss, low energy, pale mucus membranes (gums), or simply enlargement of their abdomen can be symptoms that a pet exhibits when there is a problem with their spleen.  A veterinarian may incidentally find a mass when palpating the abdomen on yearly health exams.  Splenic masses can be caused by a variety of diseases ranging from infection (abscess) to a tumor (benign vs. malignant), which is more common.  Additionally, systemic diseases or malpositioning of the spleen may also increase its overall size. Diagnostic tools veterinarians have to differentiate these multitude of diseases are x-rays (radiographs), abdominal ultrasound, CT (computed topography), and sometimes MRI (magnetic resonance imaging).

1. Normal Spleen Radiograph

1. Normal Spleen Radiograph

Radiographs give an excellent over-view of a patient’s abdomen and help to appreciate the overall size and shape of organs in comparison to the rest of the patients’ abdominal organs.  Abdominal ultrasound is superior at looking at the inside architecture of abdominal organs and can determine different characteristics of the enlarged spleen or splenic mass that help guide treatment recommendations and provide tentative prognoses.

2. Enlarged Spleen Radiograph

2. Enlarged Spleen Radiograph

3. Normal Spleen Ultrasound

3. Normal Spleen Ultrasound

The abdominal ultrasound can determine the location of a mass and whether it is associated with the spleen.  Unfortunately, tumors of the spleen are reported to be a malignant cancer more often than not.  Because tumors of the spleen typically arise from the blood vessels (hemangiosarcoma), the spread or metastasis of the tumor has already occurred at time of diagnosis and or the tumors have ruptured and are actively bleeding into the patients’ abdominal cavity.  The liver is commonly affected with metastasis of splenic cancers, so evaluation with an abdominal ultrasound can help determine if this is apparent.  Additionally, bleeding into the abdomen from the spleen can be assessed and diagnosed via abdominal ultrasound.

4. Splenic Mass Ultrasound

4. Splenic Mass Ultrasound

What are common tumors of the spleen?

The most common splenic tumor is the malignant cancer, hemangiosarcoma.  This is a tumor of the blood vessels and as a result can easily rupture and cause life threatening bleeding.  Unfortunately, diagnosis of a hemangiosarcoma requires tissue analysis (histopathology), which is typically completed with surgical removal of the spleen, and stops the active bleeding.  There are less concerning tumors of the spleen that can also rupture (hemangioma, hematomas) that once removed surgically are curative and should not affect your pet’s long term survival.  Other tumors include different sarcomas, lymphoma, and mast cell tumors (more commonly in cats).  Non-tumor diseases like infection (abscess) and splenic torsion (strangulation of splenic blood vessels), are also causes of an enlarged spleen, necessitating surgery.

What does surgery entail for your pet if they have been diagnosed with a splenic tumor or general enlargement of the spleen?

Canine and feline patients will be assessed thoroughly by a veterinarian to ensure they are stable and safe to proceed with surgery.  This typically entails complete blood work, chest x-rays, and blood type check to ensure that if a blood transfusion is needed the hospital is prepared.  Your family member will be put under general anesthesia and will have their abdomen clipped of hair for sterility purposes.  Through a long incision, the entire abdomen and abdominal organs will be thoroughly evaluated for abnormal changes.  Samples of other organs will be safely obtained if deemed necessary.  The spleen will then be isolated and removed.  Often using special vessel sealing and incising devices, LigaSure, adopted from human surgeons, will be used to safely and quickly remove the spleen stopping any current bleeding and obtaining the necessary tissue for analysis (histopathology).

5. Multiple Splenic Tumors

5. Multiple Splenic Tumors

How long does my pet need to recover from surgery?

Following their successful recovery from anesthesia, your pet will need to be in the hospital for a couple of days for close monitoring.  Blood transfusions can be common for patients that were bleeding from their masses before surgery.  Bleeding after surgery is unlikely, but possible, and this will be closely monitored.  Heart arrhythmias (irregular heart rhythm and activity) can be present that may need to be treated with medications.  As your pet improves, they will be transitioned to oral medications and prepared to discharge home for further recovery.  Typically patients need 2 weeks of strict exercise restriction and rest.  Monitoring their incision for signs of infection and supportive care with medications are the mainstay of their at home recovery.  After 2 weeks of a successful recovery, they are allowed to go back to normal activity.

If my pet is diagnosed with hemangiosarcoma, what is their prognosis?

Unfortunately, hemangiosarcoma is a very serious and debilitating cancer.  The average patient following a diagnosis of splenic hemangiosarcoma will only have a life expectancy of around 3 months.  Chemotherapy may extend survival with hemangiosarcoma and we advise meeting with one of our oncologists after a diagnosis of hemangiosarcoma to see if further treatment would be appropriate for you and your pet.  Chemotherapy is well tolerated in our canine and feline patients.  They receive intermittent injections or pills on an outpatient basis and only a small percentage (less than 15% will experience nausea, vomiting, or low white blood cells requiring antibiotics.  There are ongoing studies and trials occurring nationwide trying to find drugs that could improve survival following a diagnosis of hemangiosarcoma.

Shoulder Instability

What is shoulder instability?

Shoulder problems are one of the most common causes of front leg lameness in dogs.   Shoulder instability (SI) describes a wide range of soft tissue injuries to the ligaments, tendons and muscles of  the shoulder.  SI affects all sizes and breeds of dogs.  Many athletic (esp. agility) dogs are affected, but more sedentary pets are also affected.  At this time it is not clear if the condition is purely traumatic or a result of degeneration of the tissue.  Typical patients are middle aged, but SI can affect all ages.    SI most commonly affects a single leg, but a small percentage of pets have both shoulders affected.

How is SI diagnosed?

Fig. 1: Abduction angle: MSI: abduction angle 53.7±4.7° Normal 32.6±2 °

Fig. 1: Abduction angle: MSI: abduction angle 53.7±4.7° Normal 32.6±2 °

The starting point for diagnosis of SI is a thorough orthopedic and neurologic examination.  Once pain has been localized to the shoulder, radiographs (x-rays) are typically the next step.  It is important to note that radiographs typically do not diagnose shoulder instability, but are used to look for other causes of shoulder lameness (fractures, cancer, cartilage flaps or arthritis).  Once radiographs are taken, the next step is generally a sedated measurement of shoulder stability (shoulder abduction angle) (Figure 1).  Further diagnostic steps are dependent on this angle measurement.  Often, ultrasound is used to evaluate the soft tissues of the shoulder.

Fig. 2: MRI demonstrating normal biceps

Fig. 2: MRI demonstrating normal biceps

In some cases, MRI (figure 2) may also be required to completely evaluate the extra-articular structures and determine the best treatment options.  Cost may be rate limiting for these diagnostic tests.  In most cases, exploratory arthroscopy must be performed to definitely diagnose the problem.

How do you treat SI?

Medical management: A variety of treatment options exist for SI and depend on the type and degree of instability present.  For early cases, medical management may be the first step.  Patients are sedated and fluid sampled from the affected joint.  Long acting steroids (depomedrol 20-40mg) may be placed in the joint to decrease inflammation and pain.

Fig. 3: Hobbles by Dogleggs.com

Fig. 3: Hobbles by Dogleggs.com

Patients will often be placed in a special type of hobble to limit shoulder motion during the healing phase (figure 3).  Physical therapy is very important after the initial healing phase to regain shoulder strength.  Treatments such as laser, therapeutic ultrasound and shockwave are often used during this phase of treatment.

Platelet rich plasma (PRP) is a new therapy that involves spinning down the patient’s own blood and harvesting the platelet portion of the plasma.  This can be injected into the joint and may help stimulate the healing process.  Objective evaluation of these therapies is lacking. Water therapy (swimming and water treadmill) can be very valuable with both surgically and medically managed SI in dogs.

Fig. 4: Tightrope, minimally invasive shoulder reconstruction

Fig. 4: Tightrope, minimally invasive shoulder reconstruction

Weight control is also very important.  Overweight patients should be placed on appropriate calorie or metabolic diets.  Medical management can result in good outcomes in about 2/3 of appropriately selected patients. Dogs with significant laxity (abduction angles >60 degrees) rarely resolve with medical management only.  Surgical management:  surgical management is the treatment of choice for more severe instability cases or in those that medical management has failed.  A variety of surgical stabilization procedures are available and depend on the exact cause of SI.  Minimally invasive surgical options are always considered.  Ligament replacement surgery is often the surgical treatment of choice for SI (figure 4).  Successful outcomes with surgery approach 90%.  Patients can return to full function, but it may take 6-12 months to completely regain muscle strength.  Complications with surgery are uncommon, but include infection, failure of the repair or persistent lameness.

Portosystemic Shunts

What is a portosystemic shunt?

A portosytemic shunt (PSS) is an abnormal blood vessel that carries blood intended to flow through the liver and diverts it away from the liver to the general circulation. The portal system is a special network of blood vessels that collect blood and metabolic byproducts from many of the abdominal organs and allows passage of that blood through the liver to remove some harmful substances and derive nutrition from others. When the portal system is bypassed by a shunt, the blood flows unfiltered back to the heart and is circulated to the body, including the brain.

Portosystemic shunt as seen at surgery located in the region of the stomach and spleen.

Portosystemic shunt as seen at surgery located in the region of the stomach and spleen.

Diverse bodily functions can be impaired. Affected animals can show symptoms including:

  • Decreased alertness and appropriate reaction to surroundings most often seen following a meal(varying in severity from a puppy that seems “quiet” or “tired” to seizure activity)
  • Decreased growth
  • Abnormal urination (urinary stones can form in animals with PSS)
  • Various gastrointestinal symptoms (vomiting, poor appetite)
  • Drooling (a common symptom in cats with PSS)

PSS is seen in dogs and cats, but the majority of cases seen and treated are in dogs. The abnormal vessel is most often congenital (present at birth), and the symptoms are usually seen fairly early in life.  PSS in its most common form tends to affect small and toy breeds, although some large breed dogs can also be affected.

How is a portosystemic shunt diagnosed?

Most patients are diagnosed due to a concern for one or more of the symptoms above, but some PSS are discovered because of abnormalities in routine blood testing (such as done during a puppy or annual exam). Once there is suspicion for PSS, a blood test called a bile acids test is often performed. This is a test of general liver function, but patients with PSS will have abnormally high bile acid levels. This finding will prompt an imaging test to diagnose the presence of the abnormal vessel as well as its appearance. PSS can take many forms, so it can be important to know the shunt configuration before deciding on the nature of treatment. There are other conditions which resemble PSS on diagnostics without the presence of an abnormal vessel.

The most common methods of diagnosis are ultrasound and computed tomography (CT). Ultrasound, in experienced hands, can detect most PSS and give information about the size and location of the aberrant vessel. There is a fair amount of variation in the connection points of the abnormal vessel from one patient to another, so a “roadmap” is key to pre-surgical planning. CT is a highly useful tool for PSS diagnosis and gives detailed visual anatomical information which can be reconstructed into a 3-D format. Whether ultrasound, CT or both are used, the entire abdomen is assessed to screen for other abnormalities, including bladder stones.

How do you treat portosystemic shunts?

Most PSS are single, fairly large vessels coursing outside of the liver tissue (extrahepatic). These will be discussed. Intrahepatic shunts are located within the liver tissue allowing the blood to bypass filtration and flow directly to the heart without passing through the portal system.

Sometimes multiple shunts can be seen. These are usually not congenital, but acquired later in life and are associated with underlying liver disease and are not amenable to surgical treatment.

Medical Management

Once a single extrahepatic portosystemic shunt is diagnosed medical management should be initiated.  This treatment will help control the symptoms previously described, but does not reroute the abnormal blood flow and surgery is ultimately recommended in most patients.  Medical management often consists of the use of medication to decrease the absorption of ammonia by the intestines, antibiotics, low protein diets, and anti-seizure medications.

Lactulose can decrease the amount of ammonia absorbed by the intestines during the breakdown of proteins. Ammonia contributes to the abnormal neurologic signs in dogs with PSS.

Lactulose can decrease the amount of ammonia absorbed by the intestines during the breakdown of proteins. Ammonia contributes to the abnormal neurologic signs in dogs with PSS.

Survival times reported with medical management range from five months to more than seven years following diagnosis.  In animals with PSS, medical management is generally recommended for a minimum of two weeks prior to undergoing any form of anesthesia for diagnostic information or surgical treatment.Surgical Management

Gradual closure of PSS is considered the treatment of choice in most animals due to improved outcomes. Several different surgical techniques are available to cause gradual occlusion of the abnormal blood vessel, including the use of cellophane, ameroid constrictors, hydraulic occluders, and coil embolization.

For the majority of these techniques to be performed, the abdominal cavity must be opened along the midline to allow exposure of the liver.  The abnormal vessel is located and a device is applied around the vessel where the blood flow enters general circulation.  Cellophane bands and ameroid constrictors stimulate scar tissue formation when applied allowing gradual closure of the vessel, whereas a hydraulic occluder can be gradually inflated or deflated through injection of a port placed under the skin at the time of surgery.

Ameroid constrictor placed around PSS

Ameroid constrictor placed around PSS

Alternatively, coil embolization is performed using large catheters which are inserted through the blood vessels of the neck.  Coils are inserted from within the blood vessel and gradually result in clotting and closure of the abnormal vessel.  This technique is most frequently used with intrahepatic shunts.

A radiograph demonstrating coil embolization with a stent in the caudal vena cava and coils at the location of the entering anomalous vessel

A radiograph demonstrating coil embolization with a stent in the caudal vena cava and coils at the location of the entering anomalous vessel

If any bladder stones were noted on imaging prior to surgery, these can be removed during the same procedure through an incision into the bladder (cystotomy). Spay or neuter can also be performed.

What are the possible complications of surgery?

Following surgery your pet is monitored closely in the ICU.  Complications that can be noted following surgery include:

Hypoglycemia: Some animals will have low blood sugar in the immediate postoperative period.  If this occurs dextrose can be given in a diluted form with IV fluids.  This condition usually resolves when the pet is alert enough to eat solid foods.

Portal hypertension: Reported in 2 – 14% of patients. This complication occurs when the shunting vessel closes too quickly.  Because of the presence of the shunting vessel, the portal vein is often smaller than usual.  When blood is redirected to flow through the portal vein time is needed for this vessel to accommodate.  If too much blood is directed through the portal vein too quickly, the blood pressure in this vessel elevates rapidly causing back pressure into the intestines.  If left untreated portal hypertension ultimately results in death.  Symptoms of hypertension include abdominal pain, distension, and severe diarrhea.  If recognized immediate return to surgery to adjust the surgical site is recommended.

– Seizures or abnormal neurologic signs: Reported in 3 – 18% of dogs and 8 – 22% of cats.  Most commonly this is seen within the first three days following surgery.  The cause of this is unknown.  If observed treatment with IV fluids and benzodiazepines is initiated.  If neurologic abnormalities persist, general anesthesia for 12 -24 hours is attempted until cessation of seizure activity is noted; some animals may require 72 hours of anesthesia.  The prognosis for animals with postoperative seizures is often unfavorable, though recovery is possible.

Return of clinical signs: This can occur if a shunting vessel fails to close completely or if it closes too rapidly leading to the formation of additional shunting vessels.  Additional surgery may be recommended if either of these scenarios occur.

What is the prognosis for my pet after surgery?

Mortality rates in dogs following surgery for PSS is <10%, varying somewhat with the technique used to occlude the shunting vessel.  Mortality rates are higher in animals with postoperative neurologic dysfunction or evidence of portal hypertension.

Long-term, animals undergoing surgery for PSS have good to excellent outcomes in 80-90% of cases.

What kind of postoperative care will my pet need?

Following surgery, most pets are hospitalized for 48 – 72 hours to monitor for postsurgical complications and to administer pain medications.  Following discharge from the hospital, a specialized low protein diet is continued until blood work shows evidence of improved liver function.  Lactulose may also be continued to help reduce abnormal neurologic signs while the liver recovers.

Case Study: Thoracic Limb Lameness in French Bulldog

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Seth Mathus Ganz, DVM, DACVS

Stitch is a now 6 month old intact male French Bulldog that presented to the Veterinary
Specialty Hospital North County surgery service at 4 months of age for evaluation of left thoracic limb
lameness after jumping out of his owner’s arms. On exam, Stitch was BAR and hydrated. He exhibited a
grade 4/4 (non weight-bearing) left thoracic limb lameness with pain, swelling and crepitus in the left
elbow. Radiographs taken by the referring veterinarian demonstrated a mildly-displaced left lateral humeral condylar fracture. The treatment options were discussed with the owner. Fluoroscopic-guided closed reduction and internal fixation was elected.

Stitch was placed under general anesthesia and the left thoracic limb prepared for sterile surgery in the radiology suite. A point to point bone holding reduction forceps was used to reduce the humeral condylar fracture under fluoroscopic guidance. A selfcompressing pin was driven lateromedially through the distal humeral epiphysis. A smooth Kirschner wire was then driven from the lateral epicondyle up the lateral epicondylar crest to exit the caudomedial aspect of the diaphysis to provide rotational
stability. All of the implants were placed under fluoroscopic guidance. The implants were placed percutaneously without incisions and Stitch made an uneventful recovery from anesthesia and was discharged the following day with instructions for exercise restriction and rechecks at 2 and 6 weeks (6 weeks for radiographs). At the 2 week recheck, Stitch was ambulating without lameness and had
very good range of motion in the left elbow. At 4 weeks after surgery, Stitch represented for acute right thoracic limb lameness. A contralateral (right) lateral humeral condylar fracture was diagnosed with radiographs and repaired in a similar fashion to the left.

At this time, Stitch is fully healed from both surgeries and doing well. He did develop a seroma on the right elbow that was treated with explantation. Humeral condylar fractures are typically seen in lateral (most common, see below), medial, and bicondylar configurations. Most of these fractures are appropriately categorized as Salter-Harris IV as they propagate from the articular surface, through the
physis and into the metaphysis. There can be variable amounts of comminution present.
In our experience, humeral condylar fractures can be seen in any breed, but brachycephalic breeds and pit bull terriers seem to be over-represented. The radial head articulates chiefly with the capitulum (lateral aspect of the humeral condyle), so a jarring “jump-down” type of trauma drives the radius against the capitulum. The radial head is thought to produce a wedge effect on the intercondylar region, and the thinner lateral (compared to medial) epicondylar crest fails to produce a lateral condylar
fracture. Spaniels are heavily over-represented for a condition called incomplete ossification of the humeral condyle, which can result in chronic elbow pain or can progress to fracture. In these cases advanced imaging (CT) of the elbows and interrogation of the contralateral elbow in unilaterally-affected cases is important.

There is some clinical overlap, as spaniels can suffer true traumatic fracture and any adult dog with non-traumatic elbow-localized lameness may have IOHC. Stitch experienced minor trauma with both episodes of fracture, but his age and conformation may have contributed.
Open reduction and internal fixation has historically been recommended to perfectly restore the articular surface and provide rigid stabilization. This allows predictable and direct (without a callus) healing, avoiding osteoarthritis and impaired range of motion.
Minimally-invasive fixation is well-suited to many humeral condylar fractures because it allows excellent visualization of fracture fragments in multiple planes. This promotes accurate fracture reduction and implant placement. The other big advantage of this approach for this particular injury is that the traditional open surgical approach requires significant dissection. The closed method minimizes surgical time and trauma, allowing fast return to function.

 

Download the PDF for this case study here: Thoracic_Lameness_in_French_Bulldog.

Perineal Urethrostomy Surgery for Cats

Unfortunately, urinary obstruction (blockage) is a common and potentially serious problem in male cats. Sometimes the blockage can be caused by stones or a cancerous growth, but the most common cause by far is “feline lower urinary tract disease” (FLUTD) that can cause obstruction without a large stone or growth. The causes of this problem are complex, but the result is an inability for urine to exit the body via the urethra, which is the anatomic tube that connects the urinary bladder with the outside world.

An inability to urinate causes urine to build up in the bladder, causing potential bladder damage and, more importantly, causing an unhealthy buildup of several substances in the blood such as Potassium and creatinine. The best treatment is different for every patient and situation. A combination of IV fluids, urinary catheterization, and medications is often the first line of treatment to combat the harmful effects of the changes in the blood, relieve the blockage and help prevent early re-obstruction. Changes in diet and drinking habits can also help decrease the chance of a recurrence.

Sometimes, despite these efforts, the problem recurs. This can be shortly after the first episode or can be years later, and for some cats it can happen multiple times. In cases where it is determined that the risk or recurrence is high, or where re-obstruction happens despite multiple treatments, a surgical procedure called a perineal urethrostomy can be considered to alleviate the symptoms.

The concept behind the surgery is fairly simple, and the procedure has been utilized for some time. The cat urethra is quite narrow, and becomes even narrower as it goes towards the tip. Because most cats with FLUTD develop an obstructing plug-like substance, increasing the size of the urethral opening can help allow passage of the potentially-obstructing material before it forms a blockage. This is accomplished by opening up the urethra and using the larger part, farther in from the tip, as the new opening.

The procedure is done under general anesthesia, often combined with a local anesthetic delivered via “sacrococcygeal nerve block”, a special epidural injection. As with all anesthetic procedures at VSH, our staff (including a board-certified veterinary anesthesiologist) is meticulous about selecting anesthetic medications and monitoring patients during procedures to minimize the chance of complications.

Patient positioned for perineal urethrostomy. There is a “purse-string” suture in the anus to prevent contamination with feces.

Patient positioned for perineal urethrostomy. There is a “purse-string” suture in the anus to prevent contamination with feces.

The patient is draped for sterile surgery.

The patient is draped for sterile surgery.

The surgery is delicate and demands a high level of skill and experience as well as special equipment to be done in a consistently successful fashion. The skin around the penis is incised and dissection occurs to safely access the larger portion of the urethra. One of the key steps is making sure the dissection is done “deep” enough to make the opening as large as is safely possible. Once the right amount of dissection is determined, the urethra is cut lengthwise along the top to open up the lining of the urethra. This is meticulously sutured to the surrounding skin to promote predictable healing of the new opening. The lining of the tip of the urethra is maintained and used as a “drain board” to stay in contact with the urine as it exits the body. This is preferable to allowing the urine to contact the skin, which would cause irritation.

Keratoconjunctivitis Sicca – Dry Eye

Learn about Dry Eye from Emily Moeller, DVM, DACVO
What is dry eye? 
The surface of the eye is covered with tears that are produced by glands located around the eye.  Tears provide oxygen, sugar, proteins, and healing factors to the surface of the eye.  Dry eye is a disease of low tear production.
What causes dry eye? 
The most common cause of dry eye is inflammation within the tear glands.  The cause of the inflammation is usually unknown.  Inflammation in the tear gland interferes with tear production, and if unchecked, can cause complete and irreversible loss of gland function.
Why does dry eye matter? 
The cornea (the clear dome on the surface of the eye) relies on tears for nutrition and protection.  When tear production is low, the cornea does not receive the nutrients that it needs to survive.  The cornea will respond by developing inflammation and scar tissue to protect itself.  In the short term this can be uncomfortable, however in the long term it can lead to vision loss as scar tissue and inflammation accumulate on the cornea.
How will I know if my dog has dry eye? 
Common signs of dry eye include redness, mucoid ocular discharge, squinting, and rubbing.  Many dogs with dry eye will develop recurrent conjunctival infections due to bacterial overgrowth in the ocular discharge.  Dry eye can be diagnosed with a simple test performed by your veterinarian called a Schirmer tear test.
How is dry eye treated? 
Most dogs with dry eye show significant improvement with use of tear stimulating medications called ‘lacrimostimulants’.  Artificial tear drops can be useful, however it is important to remember that artificial tears alone will only mask the symptoms of dry eye and do not treat the underlying inflammatory process.  The two most commonly prescribed lacrimostimulants are cyclosporine and tacrolimus.  These can be provided by your veterinarian as an ophthalmic ointment or drop.  They work by reducing inflammation in the tear gland and stimulating your dog’s own tear production.  There is an excellent chance that your dog’s dry eye will improve with medications; however medications are usually required for life.

Patella Luxation

What is patella luxation?

Patella luxation (PL) is a common cause of hind limb lameness in dogs and also on rare occasion in cats.  In this condition the patella, or kneecap, is displaced from its normal resting place within a groove in the femur (thigh bone), and is instead located toward the inside of the leg (the medial surface) or outside of the leg (lateral surface).  While this condition can occasionally be due to traumatic injury, most affected animals are born with skeletal abnormalities that predispose them to the development of this condition.  Thus, this disease is typically diagnosed in the young adult to adult age dog.  The degree of lameness seen is variable depending on the severity of luxation and of the underlying skeletal abnormalities.

Figure 1A: Radiograph demonstrating the patella positioned centrally within the trochlear groove

Figure 1A: Radiograph demonstrating the patella positioned centrally within the trochlear groove

Figure 1B: Radiograph demonstrating the patella positioned outside of its normal position within the trochlear groove

Figure 1B: Radiograph demonstrating the patella positioned outside of its normal position within the trochlear groove

How is patella luxation diagnosed?

Typically the diagnosis of patella luxation is based on a thorough orthopedic evaluation.  The limping seen in early stages is often intermittent with the animal picking up the affected limb and walking on three legs when the patella is luxated, and returning the limb to the ground when the patella returns to the groove.  The severity of patella luxation is determined by assessment of how easily the patella is luxated from the groove while the hind limb is extended, or how challenging it is to return the luxated patella to its normal position within the groove.  Radiographs (x-rays) can be taken to help confirm the abnormal position of the patella and to help rule out other causes of hind limb lameness (Figure 1A and 1B).

Figure 2: CT reconstruction of a dog with abnormal angulation and rotation of the tibia and femur, contributing to MPL

Figure 2: CT reconstruction of a dog with abnormal angulation and rotation of the tibia and femur, contributing to MPL

In cases of advanced patella luxation, computed tomography (CT) evaluation with 3-D reconstruction is helpful in evaluating the limb for skeletal abnormalities that may be contributing to luxation (Figure 2).  This reconstruction also aids in the surgical planning process.

Can other orthopedic diseases contribute to patella luxation?

Patella alta, a condition where the patella sits too high within the trochlear groove, can be seen in association with patella luxation.  The uppermost portion of the trochlear groove is shallower, allowing the patella to luxate more easily during normal rotation of the limb. Patella alta can be diagnosed on x-rays with the limb in a semi-flexed position.  Correction of patella alta consists of a distal tibial tuberosity transposition, a surgical procedure during which the patella is moved downward.

How do you treat patella luxation?

In early cases of patella luxation where luxation of the patella is infrequent or minimal lameness is seen, conservative management with rest and anti-inflammatory medications may be advised.  In more advanced cases of MPL where the patella is difficult to return to its normal position or significant lameness is observed, surgical intervention is likely to be recommended.  The board certified surgeons at Veterinary Specialty Hospital are trained in several surgical techniques for repair of MPL in dogs including: (1) Trochleoplasty, (2) Tibial Tuberosity Transposition, and (3) Distal Femoral Osteotomy.  A combination of surgical techniques is often performed to achieve pain-free function of the operated limb.

Figure 3: Trochlear block recession

Figure 3: Trochlear block recession

Trochleoplasty

The goal of trochleoplasty is to widen and deepen the groove in which the patella normally rests.  By creating a deeper groove which accommodates approximately 50% of the surface area of the patella, it is more challenging for the patella to luxate to the inside of the leg (Figure 3).  During this technique the cartilage of the femur is preserved, and very little osteoarthritis is noted long term.

Figure 4: Tibial Tuberosity Transposition

Figure 4: Tibial Tuberosity Transposition

Tibial Tuberosity Transposition

The patella is connected to the tibia along its tuberosity by a very strong ligament.  The patella can be redirected to track within the groove by moving this ligament’s attachment on the tibial tuberosity toward the outside of the limb. This is accomplished by creating a controlled cut to the bone to allow the tuberosity to be placed in its new position.  The tuberosity is then stabilized in the new position with wires or pins (Figure 4).  When correcting for patella alta, the tibial tuberosity is shifted downward (distally) to direct the patella to a deeper portion of the trochlear groove.

Figure 5: Radiographs performed immediately postoperatively of a DFO. Note the area where bone has been removed to allow the femur to be straightened (blue arrow)

Figure 5: Radiographs performed immediately postoperatively of a DFO. Note the area where bone has been removed to allow the femur to be straightened (blue arrow)

Distal Femoral Osteotomy

In large breed dogs diagnosed with patella luxation, abnormal bone conformation can contribute significantly to patella luxation.  These abnormalities lead to a bow legged stance causing increased tension on the patella to be drawn medially.  The presence of these abnormalities is determined by evaluating radiographs, or a CT scan, to look for inappropriate angulation of the femur near the knee.  To correct the angulation, a cut in the bone (osteotomy) is created to allow the limb to be straightened (Figure 5).  A bone plate and screws are used to stabilize the osteotomy until healing is complete.

In general, the prognosis for return to pain-free function following surgery is good, with more advanced luxations having more difficulty in recovery.  Following an initial 2-3 week period of extreme exercise restriction, a gradual increase in controlled activity is permitted; total recovery time following surgery is generally between 8-12 weeks.  Your surgeon will review specific recommendations regarding postoperative rehabilitation during the initial consultation and follow-up visits.  Postoperative physical rehabilitation, in some cases, can maximize the positive outcome and shorten the rehabilitation period.  Fortunately, the majority of dogs do not require additional physical therapy beyond leash controlled activity at home.  Potential complications exist for any orthopedic surgery and include infection, implant failure, and incision complications.  An experienced surgeon and appropriate postoperative care significantly decrease the risk and negative effects of these complications.

Management of Canine Arthritis (Osteoarthritis)

What is arthritis?

Osteoarthritis is an irreversible condition in our canine patients.  However, with appropriate medical therapy, most pets can live long, happy, pain-free lives. There are numerous conditions that can lead to the development of osteoarthritis including: hip dysplasia, cranial cruciate ligament injuries, osteochondrosis dissecans, and elbow dysplasia (fragmented medial coronoid processes, ununited anconeal processes, and elbow incongruity). There are numerous ways to help limit the effects of osteoarthritis on your pet’s life.

 

How can I manage the impact of arthritis in my pet without surgery?

Weight Loss:

Excess weight places undue stress on the joints and can accelerate the progression of arthritis.  Even if your pet is not overweight, decreasing his weight will decrease the stress on his joints. The primary components of a weight loss plan include a decrease in caloric intake and an increase in quality exercise.

-Decreasing caloric intake can be accomplished by decreasing the total volume of food consumed or by switching your pet to a lower calorie diet.  Prescription diets (such as Hill’s r/d or w/d or Purina OM) can be used until a desired weight is achieved.

-Increasing activity level also helps with weight loss by increasing the number of calories burned.

-In order to establish a successful weight loss program, it is imperative that you remain in close communication with your primary veterinarian and schedule weekly to bimonthly weight checks.  Once a routine is established, the veterinarian can fine-tune your pet’s weight loss program to a safe and acceptable rate.

-Ideally your pet would be limited only to his prescribed weight loss diet but we understand that some pets enjoy food treats in addition to the regular food.  Please avoid all over the counter pet treats as these are usually high in fat, salt, and calories.  Instead consider feeding such things as frozen green beans or carrots in small amounts. You can also use dog food as treats, remembering to decrease the amount fed at mealtime as well. Avoid onions, garlic, nuts, grapes, and raisins as these are toxic to pets.

-In addition to appropriate caloric restriction and exercise, an oral diet medication (Slentrol® (Pfizer)) can be prescribed to help control hunger and further accelerate weight loss.  This medication is available only by prescription and is not right for every dog, so please discuss the use of this medication with your primary veterinarian.

Exercise:

-Promoting exercise in your arthritic pet is very important for weight loss and helps lubricate the joints. We recommend low impact exercises, such as controlled leash walks or swimming. Walks on softer surfaces, such as grass, will decrease the impact on his or her joints, as well. We recommend starting slowly with any activity and gradually working your pet up to additional activity. This may mean starting with 5 minute walks, three times per day, and gradually increasing by 5-10 minutes each week until you reach 30 minutes, three times daily.

-If your pet has lost significant muscle mass, physical therapy with a pool or underwater treadmill may be beneficial to improve muscle mass prior to attempting walks on your own. If you are interested in water therapy with a pool or treadmill we can provide you with the names of local rehabilitation facilities that specialize in aquatherapy.

-If at any time your pet experiences increased lameness or pain following activity, please stop all exercise for 24 hours. If the lameness continues, please see your veterinarian or any of the veterinary surgeons at VSH for a physical examination. If the lameness resolves you may resume activity at a lesser amount and gradually work back up to longer walks.

Nutraceuticals:

Nutraceuticals, herbal/natural products and complimentary /alternative medications are products that are intended to aid in disease management, but they are not regulated by the Food and Drug Administration (FDA). Rigid quality control standards are not required for these products, and as a result substantial variability can occur in both the potency and the purity of these products.  Few well-controlled clinical studies have been performed in animals documenting the use of these products; however, some products have been shown to have beneficial effects in humans and animals. When choosing a product labeled for human-use for your pet, always consult with your veterinarian. The United States Pharmacopoeia (USP) is a standard-setting authority that certifies nutraceutical products and requires testing to ensure the purity, potency, and quality of finished products. Look for their stamp of quality on products you buy.

Glucosamine/Chondroitin sulfate: These compounds are naturally occurring within the joints. They are part of the structure of normal cartilage and are thought to help with cartilage repair. Glucosamine/chondroitin supplementation has been shown to improve comfort/pain control in humans. No similar studies have been performed in canine or feline patients. Several products have been shown to contain appropriate levels of available glucosamine and chondroitin including Cosequin®, Dasuquin™ (by Nutramax) and Seraquin® (by Boehringer Ingelheim). These are available only through veterinarians. The ideal starting dose would be 1500 mg per day of the glucosamine portion.  This dose can be divided and given twice a day.

Omega 3 fatty acids: These are a family of unsaturated fatty acids that cannot be made by the body and are required in the diet. These include ALA, EPA, and DHA. These products are especially concentrated in certain foods like cold water fish, such as salmon, herring, mackerel, anchovies, or sardines. They are thought to help block enzymes that can degrade cartilage and reduce the creation of substances that cause inflammation. The ratio of omega 3 to omega 6 fatty acids may be more important than the actual amount of omega 3 fatty acids consumed; this is controversial and the specific ratio and dose has not been determined for our pets, but is assumed to be similar to humans.  Fish oil products are especially sensitive to the effects of heat, light and oxygen exposure. Be sure to store the products exactly as is recommended. One product that has been shown to contain the labeled amount of EPA and DHA that is recommended is Omega-3 Pet™ by Nordic Naturals® but there are many products available. Currently we recommend Nordic Naturals® which can be purchased at your local health food store.  When using Nordic Naturals® use the label dosage appropriate for your pet’s weight.  Fish oils can be started at 1000-1200 mg per day.  Many other products are available and you can consult with your veterinarian for additional options.

Adequan® (by Lutipold): This is a polysulfated glycosaminoglycan (PSGAG). PSGAGs are similar to the main component of joint fluid and cartilage. They are thought to help decrease inflammation in the joint and protect healthy cartilage. Adequan® is a prescription, water-based product to be injected into the muscle that can be given on a tapering regimen. It can be started weekly or twice a week for a month and tapered slowly over time. These can be given by your primary veterinarian, as injections to give at home, or by a surgeon at Veterinary Specialty Hospital.

Hyaluronic acid (HA): This is a naturally occurring substance found within joints. It is made by cartilage cells and helps support the composition of joint fluid and decrease inflammation within the joint. This product is rarely used in companion animals and is usually injected directly into the joints. There are several products containing HA that are available as food supplements, however the effectiveness of orally administered HA is unknown. There is substantial variability between products and an HA supplement should be chosen only when other products have not been effective.

Diets:

Several commercially prepared prescription diets are available that contain high levels of omega-3 fatty acids and glucosamine/chondroitin. They are additionally formulated to help decrease inflammation. These diets include Hill’s Science Diet J/D, Purina JM, Iams® Veterinary Formulas Joint Health, and Royal Canin Mobility Support JS. The amount of omega-3 fatty acids contained in Hill’s Science Diet J/D eliminates the need for fatty acid supplementation. These products do not contain therapeutic levels of glucosamine/chondroitin and you should continue to supplement your pet while on these diets.

Unfortunately these diets are only formulated for dogs. Additionally, if your pet is on a hypoallergenic diet or has food allergies, these diets are not recommended as most contain chicken, rice, and wheat products. These diets are not considered weight loss formulas and care should be taken to ensure that your pet does not gain weight while on these diets.

Please contact your veterinarian or their office to purchase these prescription diets.

Non-steroidal anti-inflammatory drugs (NSAIDs):

This is a class of prescription medications that act to decrease inflammation by blocking the mediators of inflammation at a point along the pathway. By blocking these inflammatory mediators, there is also a decrease in pain. This group of drugs includes Rimadyl® (carprofen), Deramaxx® (deracoxib), Metacam® (meloxicam), Previcox® (firocoxib), Zubrin® (tepoxalin)and Etogesic® (etodolac). These medications act similarly to several human medications including aspirin, ibuprofen (Motrin/Advil), Aleve, and Celebrex.

NSAIDs should never be given without the supervision of your veterinarian. These products can cause serious, life-threatening side effects, even in small doses.

NSAIDs are often used intermittently to control pain secondary to osteoarthritis, but can be used on a long-term basis. It is important to monitor your pet’s kidney and liver function at least every 6 months if he or she is administered NSAIDs long term. This monitoring is important for continued treatment.

The most common complication of NSAID use is stomach/intestinal upset. If any vomiting, diarrhea, or a decrease in appetite occur while giving an NSAID, please stop their use immediately and contact your veterinarian, or a veterinarian at VSH immediately.

Alternative Therapies:

-Acupuncture: Some previous clients have mentioned the benefits gained from acupuncture therapy.  Although we do not perform this procedure here at VSH there are many local veterinarians who have training in this procedure.

Stem cell therapy: Stem cell therapy has recently received a large amount of attention in the press. It was initially used in horses to help stimulate the repair of tendons and ligaments. Its use in companion animals has been more recent and as of yet there has been little scientific data to prove its efficacy. As there is significant expense associated with the procedure and little clinical data to support its use, we do not currently recommend the use of stem cell therapy.  We will continue to monitor the objective research in the field of stem cell therapy and consider forms of appropriate treatment when they become available.