Perth Animal Surgery
Perth Animal Surgery was founded on, and is still guided by, the principle that the most important aspect of our work is ensuring the best outcome for the patient entrusted to our care. This principle guides us in all our discussions with owners and dealings with our patients. We take our responsibility in this regard very seriously.
Perth Animal Surgery was the first privately-owned specialist veterinary surgical practice in Western Australia – operating now for over 18 years. Dr Tim Caporn established the practice under the name of Animal Surgical Referral Service in Cottesloe in 1994. In 2009, Dr Caporn moved the business to Osborne Park, establishing Perth’s first private multidisciplinary practice, Perth Veterinary Specialists, with the owners of the Imaging and Oncology/Medicine practices. The name of the practice was changed to Perth Animal Surgery in 2012.
Perth Animal Surgery currently has three specialist surgeons, Dr Tim Caporn, Dr Karen Staudte & Dr Ramesh Sivacolundhu. They are supported by a team of highly experienced, qualified personnel, including surgical interns, nurses and office staff.
Having a surgical specialist practice in the same building as advanced imaging facilities, medicine specialists and an oncology practice provides the pet owners and veterinarians of Western Australia with unsurpassed diagnostic and therapeutic options to ensure the best possible outcome for your pet.
This, together with our emphasis on “putting your pet first”, aims to ensure your pet’s time with us will be stress-free for both you and your pet. You can be happy you are providing your pet with the best of modern veterinary care, to keep them safe and make them well again.
Stem Cell Therapy For Your Dog
Perth Animal Surgery is proud to announce its collaboration with the Sydney based regenerative medicine company – Regeneus. This will allow us to treat arthritic patients with CryoShot™ an “off the shelf” stem cell treatment for canine arthritis.
This handout answers some of the most commonly asked questions you may have regarding this treatment option and the outcome we hope to achieve for your pet.
What is Stem Cell Therapy?
Mesenchymal Stem Cells (from adult fat) are injected into a joint. In the joint they have two main effects. The first effect is to reduce inflammation and pain. They have also shown to stimulate the resident cartilage cells to grow – leading to long-term clinical improvements for your dog.
Where do the Stem Cells come from?
The stem cells used in CryoShot™ are obtained from the excess fatty tissue from donor animals, which is removed at the time they are sterilised. (This tissue would otherwise have been discarded). This tissue is then processed to isolate the regenerative cells and stored in liquid nitrogen. Every batch produced, is subject to stringent safety and quality control procedures.
How is it used?
CryoShot™ can be used in a variety of ways.
If your dog is being treated for arthritis they will be sedated, the affected joint clipped and thoroughly cleaned before a needle is placed into the joint. The CryoShot™ vial will then be removed from the liquid nitrogen, thawed and injected directly into the joint. Your dog will then be woken up and discharged the same day.
If your dog is having joint surgery, the Cryoshot™ can be injected into the joint after surgery is finished to aid recovery and reduce arthritis.
We have also trialled it as an aid in helping to heal ruptured achilles tendons that have been surgically repaired and to promote the healing of broken bones.
What do I need to do after treatment?
Your dog should be kept quiet for the first 24hrs after sedation with no walks other than to go out to the toilet. Your dog should then be rested for 2 weeks following the injection with short walks only before being allowed to resume their usual activity levels.
Are there any side effects?
Swelling and inflammation of the joint is uncommonly seen after a joint injection. If the joint gets hot or swollen, your dog goes very lame or stops eating, please contact us immediately.
How long until I see a result?
Studies have shown that some benefit is seen within the first 2 weeks. The maximal effect is often seen between 1-3 months post injection, and the effect has been found to last several years. Owners usually find they can reduce the amount of pain relief they need to give their pet and occasionally they can stop them all together.
It is important to appreciate though, that whilst your pet feels better in the first few weeks after treatment, the underlying problem has not yet gone away. It may take a number of months before the treated joint may be healed. So if you know your dog has a really bad joint (or two), even if it is feeling good, don’t make it run a marathon!
When does my pet need another injection?
This is a good question. Stem cell therapy is relatively new, and no extensive multiple injection follow up data is yet available. However, Regeneus is working hard to obtain this data. The effects for single injections have lasted several years however there is no research to indicate multiple injections are bad for your pet. Contact us again if you feel they require another injection and we can discuss that with you.
Can this be given to my cat?
No. Unfortunately all the current research on CryoShot™ is in dogs and horses. CryoShot™ is not yet available for cats.
Who is Regeneus?
Regeneus is a Sydney-based regenerative medicine company that develops and commercialises proprietary technologies for the preparation of in-clinic and off-the-shelf cell therapies using adipose (fat)-derived regenerative cells including mesenchymal stem cells for the treatment of musculoskeletal and other inflammatory conditions in humans and animals.
HiQCell™, an in-clinic autologous cell therapy for the treatment of osteoarthritis and tendon and ligament injuries, is available in Sydney through a number of licensed medical specialists. HiQCell™ will soon be available through medical specialists in other capital cities.
AdiCell™ is an in-clinic autologous cell therapy for the treatment of canine and equine musculoskeletal conditions. This therapy has been available through Regeneus’ vet partners since 2008, in Australia, New Zealand and the UK. In March 2012, Regeneus announced positive trial results from CryoShot™, a new off-the-shelf allogenic stem cell therapy for the treatment of canine and equine musculoskeletal conditions.
Luxated hips requiring open reduction may be stabilised by a number of methods. Toggle pinning is mechanically very effective and applicable to a wide range of body weights.
Hip Dysplasia Treatment
Treatment options for HD can be divided into early and late. Early options ( JPS & TPO) seek to target laxity and conformational problems to eliminate or reduce undesirable remodelling and future osteoarthritis. Juvenile Pubic Symphysiodesis (JPS) is a highly effective preventive measure for those pups identified to be at high risk of HD. Pups must preferably be assessed by 14 weeks of age. TPO is a well established effective means of rescuing lax hips from HD if performed prior to significant articular damage. Darthroplasty is an intermediate option which may be applicable in some dogs. Late options include excision arthroplasty and THR.
Limb Deformity Correction
This 4 mth-old Maltese-cross presented with severe deformities resulting from “short ulna syndrome”. An ESF was used to stabilise the bones after definitive corrective osteotomy. The ESF was removed at 8 weeks postop
Cruciate Ligament Surgery
PAS was the first clinic in Western Australia to utilise a tibial osteotomy technique in treating cranial cruciate ligament (CrCL) diease. We have treated over 700 dogs this way and currently employ Triple Tibial Osteotomy (TTO) as our standard technique. These tibial osteotomy techniques differ fundamentally from the extracapsular & intraarticular repair techniques. Stability aiaginst cranial tibial drawer is gained through altering the biomechanics of the stifle so the need for a CrCL or similar stabiliser is greatly reduced. Our experience has been that TTO and TWO are more reliable in producing good to very good limb function in all weight ranges, with minimal progression of osteoarthritis
Arthrodesis may be employed as a relatively early treatment for severe ligamentous injury or as an end-stage rescue procedure to eliminate intractable pain.
Soft Tissue Surgery
CHEST WALL MASSES
Masses or tumours of the chest wall come in many shapes, types and sizes. They can originate from the skin, soft tissue, muscle or bone and may be confined to a small area or be very extensive. Ideal management of these cases often requires a surgical biopsy to determine the cell type (eg infiltrative lipoma versus chondrosarcoma versus histiocytic sarcoma). A CT scan can determine the extent of the mass and facilitate surgical planning. Up to six ribs can be removed from the chest wall of some patients with full return of function, whereas in other cases the mass may be best treated by partial removal and then follow-up chemotherapy. Large mass resection may require reconstruction of the thoracic wall with techniques such as muscle and skin flaps, diaphragmatic advancement and prosthetic mesh insertion. Pre-operative surgical biopsies need to be taken in a way that does not compromise future resection of the entire mass. Several short term complications can arise from chest wall surgery, such as lung reperfusion injury, blood loss, pneumothorax and large seroma formation. Our skilled staff and excellent facilities are ready to manage these issues, however this means the patient may stay in hospital for 2-7 days after a major surgery.
LUNG TUMOURS and MASSES
Lung cancer is uncommon in dogs and rare in cats. Patients often present with a cough but few other symptoms, despite having a large area of lung lobe affected. Surgery can return quality of life for many months or cure the patient, depending on the location and type of the tumour. Pulmonary carcinoma is the most common. Other causes of lung masses include grass seeds, abscesses, and granulomas.
Dogs and cats have several lung lobes. Depending on the tumour location, one or more lobes may need to be removed. Patients can return to excellent athletic function after lung lobectomy, once their bodies adjust to the change.
Surgery to remove a lung lobe is planned well in advance (excepting emergency surgery for lung lobe torsion, which is performed as needed) and patients stay in hospital for 2-5 days post-operatively.
The removed lung lobe is sent for histo-pathological analysis, and often for culture and sensitivity testing. This helps us understand the underlying cause, and plan treatment to prevent relapse or recurrence.
Soft Tissue Sarcomas
Soft tissue sarcomas include anaplastic sarcomas and histiocytic sarcomas and other undifferentiated growth of mesenchymal type cells. They can develop anywhere in the body, but are detected as a progressively enlarging semi-solid lump on the extremities (eg near the carpus, within the thigh or shoulder muscles, on the hock). They can grow at variable rates, and that rate can change. Liposarcomas- a fatty growth that behave in an aggressive way, have a similar appearance. The tumours are best removed early, before they interfere with ambulation. Because of their aggressive and invasive nature, wide margins are often required for successful removal. This may include up to 5 cm of normal tissue around the mass and one fascial plane or muscle layer beneath the lump. A combination of biopsy, ultrasound or CT scan may be used to determine the exact location and extent of the growth, to understand prognosis and aid surgical planning. Some masses respond better to a combination of chemotherapy and surgery, either before but usually after surgery.
CT scan showing Suzie’s soft tissue sarcoma in the serratusventralis, a muscle located between the shoulder blade and the rib cage. Suzie had a limp and a small lump protruding from her shoulder, but a large growth extending for 8 cm underneath the skin. It was successfully completely removed, thanks to the information gained from the CT scan.
Reproductive Tract/Urinary Tract Surgery
Young dogs may be incontinent due to a congenital anomaly, such as ectopic ureter or urethral sphincter mechanism incompetence (USMI). Ectopic ureters can be re-implanted into the bladder, improving or restoring continence. Prior to this surgery being performed, ultrasound, CT and/or cystoscopy is used to identify the size, location and health of the ureters and the kidneys they drain to determine prognosis and detect underlying infection. Occasionally we need to remove a deformed or damaged kidney, this is done at the same surgery. Concurrent or isolated USMI can be managed with medical therapy, or if unresponsive, colposuspension.
Motor vehicle accidents can cause rupture of the bladder, tearing of the ureters or avulsion of a kidney. Leakage of the urine into the abdominal cavity is gradually toxic to the patient, and, can cause severe illness or even death over a 2-10 day period. Leaks and tears are detected using a combination of observation, blood and urine tests, and use of contrast dyes injected intravenously or via the urinary tract. These injuries are often associated with other injuries such as fractured pelvis, skin lacerations and rib fractures. Before the surgery, the patient must be stabilised to treat metabolic and electrolyte imbalances caused by urine accumulation. After repair of the leak or tear, the patient may require ongoing hospitalisation with an indwelling urinary catheter whilst the tract heals, for 2-7 days. Healing times depend on the severity of the injury.
Plastic & Reconstructive Techniques
Liver tumours in dogs tend to be massive carcinomas, up to a basketball in size. This is not as bad as it sounds! These primary masses (occurring in the liver only) can be slow growing, and completely cured once resected. They are not simple surgeries however, as a result of a large and complex blood supply to the liver and surrounding organs. Use of automated staplers, special instruments for dissection, and sophisticated anaesthetic techniques are employed to minimise surgical time and risk. Up to 80% of the liver can be safely removed, and it will regenerate, however some central areas are essential to function and are irreplaceable. Pre-operative assessment of the patient is essential to determine prognosis (long term outcomes). This includes checking blood clotting, performing an abdominal ultrasound, and preferably a thoracic and abdominal CT scan. However the final decisions on surgical resection are made during surgery, and this is where having an experienced soft tissue surgeon becomes invaluable.
Laryngeal paralysis occurs when there is loss of function in the laryngeal muscles that normally open the larynx when an animal breathes in. The condition is caused by degeneration of certain nerves involved in normal breathing, and it results in airway obstruction causing noisy respiration. Laryngeal paralysis tends to affect mature age, large and giant breed dogs. Classically, these patients often present in late spring and early summer with progressive exercise intolerance or signs of heat stroke (constant panting, collapse, bright red mucous membranes, raspy breathing). Many dogs are affected by a degeneration of the nerve to the larynx (idiopathic). Some unluckier patients will have an underlying cancer of the larynx or mediastinal area, or hormonal or other medical disease that is altering nerve function. Patients are usually evaluated with full blood tests and chest xrays as well as examination of laryngeal function under a safe anaesthetic prior to surgery. Other tests are advised if clinically indicated. Treatment, which is effective in 90% of patients with idiopathic laryngeal paralysis, involves surgical abduction of one side of the larynx (“tie-back” procedure). This is a permanent alteration of the airway, allowing better air flow into the lungs. Patients recover quickly, but must wear a chest harness instead of a neck lead after surgery. They are fed slowly, to decrease the (low) risk of aspiration pneumonia. Although many patients are 12-14 years of age when they develop this condition, age is not a disease or reason not to proceed. We discuss carefully with the owners what quality of life their pet currently enjoys and what they can expect after the surgery has been performed.
Hernias can result as a congenital deformity, secondary to trauma or chronic straining. Some hernias require emergency surgery due to strangulation of organs.
Hernias that are successfully treated include:
Hiatal hernia- when the stomach slides through the diaphragm, into the chest within or next to the oesophagus. Most commonly seen in English Bulldogs, French bulldogs and Shar Peis. This is treated with oesophagopexy, gastropexy and phrenicoplasty.
Diaphragmatic hernia: most often seen in cats and dogs after a motor vehicle accident. Sometimes it is not detected until months after the accident occurred. The stomach, liver, spleen and intestines may slide into the chest cavity, interfering with lung function. These organs are replaced in the abdomen (or removed if needed) and the tear(s) in the diaphragm closed.
Inguinal hernia, scrotal hernal, umbilical hernia: displaced organs are repositioned and the defects safely closed.
Perineal hernia: Thorough investigation into the underlying cause of a perineal hernia is essential. Breeds such as Border Collie have an inherent weakness of the pelvic diaphragm muscles. Many other breeds develop perineal hernia as a result of straining to defecate or urinate. The common underlying causes of this include prostatic disease, such as benign prostatic hyperplasia, colonic or rectal disease such as IBD, polyps or carcinoma, or cystitis, due to calculi formation with concurrent infection. Less common causes include prostatic or rectal adenocarcinoma, sarcoma of the pelvic canal, megacolon and narrowed pelvic canal due to previous fracture. These problems are best detected using clinical examination, and/or radiographs, ultrasound, CT or colonoscopy and FNA of relevant organs. Each case must be assessed on its own merits. Surgery can be done on one side or both at the same time, once again depending on the case.
Hernia repair may entail movement of the internal obturator, superficial gluteal, semitendinosus muscle or insertion of a prosthetic mesh.
Foreign Body Removal
A common surgery we perform is to remove foreign bodies from the gastro-intestinal tract of dogs and cats that eat materials such as parts of stuffed toys, scouring pads, carpet, plastic bags, string, sewing needles, bones, socks and underwear! These items can get stuck in the oesophagus (95% of these can be retrieved by endoscopy), stomach, or intestines (often at the ileo-caecal valve). Other foreign materials, such as grass seeds and sticks, can be accidently swallowed, inhaled or penetrate the feet and skin and work their way to remote sites. One of the most common places for migrating grass seeds to go is under the lumbar spine, forming a small abscess close to the aorta. These are best located using ultrasound or a CT scan, and removed with extreme care by our soft tissue surgeon. Animals can suffer recurring fever, pain, draining sinuses and debilitation until the foreign material is completely removed. Foreign bodies lodged in the gastrointestinal tract can lead to life-threatening infections and eventual death if not treated.
Total Ear Canal Ablation and Bulla Osteotomy (TECABO)
TECABO is used to treat chronic inflammation or cancer. Chronic inflammation as a result of life-long allergies or congenitally stenotic ear canals leads to pain and secondary thickening and infection of the ear pinna and canal. The entire canal can be safely removed, alleviating symptoms. The tympanic bulla (bony part of the skull that the ear canal originates from) must be opened up as well, to facilitate drainage of infection and debridement of the origin of the canal epithelium. Hearing is often impaired pre-operatively, but is not worsened by the procedure.
Pinna surgery is performed to remove sarcomas, treat lacerations and aural haematomas, if required. White eared cats with solar damage causing squamous cell carcinoma can have the majority of the pinna removed to manage this disease. Skin flaps (movement of skin including a vascular pedicle) can be utilised to manage skin tension/tissue defects if radical surgery is needed.
Subtotal pericardectomy involves removal of the lower 2/3 of the pericardium (heart sac) to allow fluid to drain into the thoracic (chest) cavity. The fluid may be present because of cancer (often mesothelioma, occasionally haemangiosarcoma) or a condition called idiopathic pericardial effusion, where no known cause can be detected, but the problem is recurring and life-threatening. If excessive fluid is trapped within the pericardial sac, the heart cannot expand to pump blood, and rapidly fails.
Subtotal pericardectomy can be performed with surgical access between the ribs in most situations. If there is restrictive pericarditis, where the heart sac has become fibrotic from chronic inflammation, or a tumour mass must be accessed from a particular direction (eg left heart base) the surgical approach may be altered. Restrictive pericarditis is more likely when the fluid has been drained several times via needle already (pericardiocentesis).
The risks of cardiac surgery include arrhythmias, blood loss, nerve injury and pleural effusion. Consultation with the surgeon occurs before every case goes to surgery, and is essential for understanding the risks and long term outcomes expected for this surgery.
Radiograph of a 70 kg canine patient after pericardectomy to treat congential pericardial cysts. The sternum has been closed with wire.
PATENT DUCTUS ARTERIOSUS
Patent ductus arteriosus (PDA) is a congenital defect seen in all dogs but is more common in Border Collies, German Shepherds, and other purebred dogs.It tends to affect females more than males. It is often detected at puppy vaccinations and should be treated at an early age, preferably before 4-5 months of age. The longer it is left untreated, the more secondary degenerative changes occur in the heart muscle and valves. Diagnosis is confirmed by echocardiogram (ultrasound of the heart) which shows the heart vessel (ductus) which failed to close at birth.
Surgery has a very high success rate (99% are permanently cured). Surgery involves opening the chest between the ribs to access the heart. The ductus is dissected free and tied off (ligated). Patients recover very rapidly and must be confined after surgery to ensure they rest- as puppies they just want to play and play with their new-found energy!
Brachycephalic Obstructive Syndrome
Brachycephalic obstructive syndrome (BOS) is a condition affecting Bulldogs, Pugs, Cavalier King Charles Spaniels and other Brachycephalic breeds with very short noses and flat faces. These patients are extraordinarily cute, but have limited respiratory capacity as a result of narrowed nostrils, elongated soft palate, extra-large tongues and narrow tracheas. Secondary changes develop in the soft tissues of the throat/pharynx, larynx, and trachea resulting in collapse of the airways, incredible snoring and breathing noises, and eventual exercise intolerance, heat stroke and collapse. The condition can be improved by surgically trimming the soft palate to a safe length, removing the abnormal tissue, and opening up the nostrils. In severe conditions, the trachea can be supported, either internally or externally. Medications and dietary management of this condition are also essential and can help to dramatically improve symptoms. Young brachycephalic patients (age 6+ months) can benefit from early surgery to delay or halt progression of the symptoms.
Stomach, intestines, liver, spleen, kidneys, adrenal glands, the list goes on. A lot of vital organs exist within the abdominal cavity, and illness in one can upset the balance in the rest of the system. Whether the original problem is trauma (eg hit by car) or cancer or something the patient ate (such as a cooked bone), determines what surgery is required. Sometimes the problem is obvious, sometimes a series of tests such as blood analysis, x-rays, ultrasound and CT scan are required to fully understand the extent of the problem and the patient’s prognosis.
We are fully equipped to deal with all manner of abdominal surgery. Examples of diseases we treat include:
Liver: mass removal, biopsy for disease, portosystemic shunts, liver lobe torsion
Gall bladder: removal, diversion, flushing and stenting of the common bile duct
Spleen: partial or complete splenectomy for mass removal, splenic torsion
Stomach: gastric torsion, gastric dilation, mass removal, treatment of pyloric stenosis, preventative gastropexy, foreign body removal, G-tube placement, duodenal bypass,
Intestines: removal of obstructive foreign bodies and masses, mesenteric torsion, intussusception, megacolon, disease within the colon and rectum, duodenal perforation, peritonitis.
Kidneys: nephrectomy, opening of the renal pelvis to remove stones, biopsy
Ureters: torn, transected or ligated ureters re-anastomosis, ectopic ureter re-implantation
Bladder: removal of stones, tumours, ruptured bladder, urethral sphincter mechanism incompetence, urethrotomy.
Adrenals: mass removal, including those with caval invasion, if required and appropriate.
Pancreas: biopsy, partial removal, insulinoma removal
Ovaries/uterus: caesarean, spey, uterine torsion, tumour removal.
Not on the list? Please ask, these are examples only of what we can do?
Some spinal tumours respond very well to surgery, and if required, follow up radiation therapy. These are typically meningiomas or other benign space-occupying growths within the spinal canal. Symptoms may have had a gradual onset, but an acute presentation is not uncommon, and is due to minor trauma leading to, or spontaneous haemorrhage from the tumour. Cancer that involves the bones of the spinal column such as osteosarcoma or metastatic disease from a primary carcinoma such as pancreas, prostate, thyroid or anal gland carry a poor prognosis and are rarely operated on.
ASRS has operated on hundreds of animals’ spines for various conditions. One of our main imaging tools has been myelography. At PVS we are able to work with the specialist imaging team to take advantage of the improved diagnostic capability of the CT and MRI facilities.
Post Operative Care
Care after surgery
Please read these notes together with our forms covering bandage care and postoperative care for TTO and TWO procedures (Part B). There are three components to caring for your dog after this surgery – controlling pain, caring for the bone as it heals and caring for the joint. Maximise the chances of good results by following a very slow progressive return to activity
Time since the surgery recommendation
Up to 2 weeks:
very short leash walks to “toilet” only return to us for bandage removal and checkup at 10 to 14 days postop
2 to 4 weeks:
strict confinement when not on a leash leash walks as above, with some longer walks around garden only
aim for a number of very short walks per day passively gently flexing and extending the limb may be useful in some dogs
4 to 7 weeks:
strict confinement when not on a leash
longer leash walks can commence inside or outside your property, but only increased in distance if the leg is being used confidently without any obvious discomfort. How far you are walking at this stage will depend very much on how comfortable your own dog is. Some dogs will need to progress very slowly. If uncertain, start the week with a very gentle 3 minute walk 3 to 5 times a day and end the week with a 5 minute walk 3 to 5 times a day. Build the length of walking time up by 2 to 5 minutes per week. By the end of 7 weeks postop, some dogs may be able to walk for 15 to 20 minutes 3 to 5 times a day, others will not be up to this level. Always tailor the walking to your individual dog. You are overdoing it if your dog becomes tired or sore or lame by the end of the walk. Do not push your dog past a level at which they feel comfortable. If your dog is coping very well, try and do more sessions of walking per day, rather than increasing the length of the walks too much at this time. Swimming can be useful only if great care is exercised getting into and out of the water. You must still avoid any rough activity (jumping, running, other dogs etc)
7 to 8 weeks:
Return to us for a check x-ray of the leg to see if the bone has healed solidly.This will be a visit for the day. (The cost of this procedure is not included in the initial surgical costs).
2 to 3 months:
If the go-ahead has been given for more exercise; you may be able to progressively increase the length of the leash walks and the level of activity. This should be done with great regard to your own dog’s capability, The knee joint usually cannot withstand normal activity levels without some degree of soreness or injury before 3 months postop.
3 months onwards:
If long leash walks of 30 minutes or more have been well tolerated with no soreness, free activity off the leash may be allowed.
Remember, these recommendations are just that, recommendations. Your own dog may progress more quickly or more slowly than this. Always call us if you are unsure how you should be progressing with your own dog. Some dogs may require physiotherapy or careful use of pain killers or anti-arthritic agents to aid their recovery.
Finally, remember that your local, primary care veterinarian plays a vital role in assisting your pet’s recovery, particularly over the longer term.
The cruciate ligaments in the dog knee joint (stifle) play a very important role in stabilising the joint. The cranial cruciate ligament (CrCL) is the most important of these. Its role is to limit the internal rotation (twisting) and extension (straightening)of the stifle. It also has a very important role in limiting the cranial or forward movement (cranial “drawer”/ instability) of the tibia bone.
Cranial cruciate ligament disease
Many dogs develop disease of the CrCL. This may be precipitated by an injury or arise through the stresses of normal activity. Once the CrCL is damaged, it is usually painful for dogs to bear weight on the leg, so they will appear lame. They may be lame all the time, only when walking or running, or only pick up the leg when standing. If left alone, the CrCL damage will tend to progress to complete rupture of the ligament. Over time, the instability of the stifle and the damaged ligament inside the joint will promote arthritis in the joint. The best results from CrCL surgery in the dog occur when surgery is performed sooner rather than later – before arthritis becomes entrenched.
Fixing the problem
There are three main ways of addressing CrCL damage in dogs. For many years, veterinary surgeons have used material, either external to the joint (heavy suture materials), or internally in the joint (using the body’s own tissue) to “tighten” and stabilise the joint. These techniques attempted to stabilise the stifle independently to weight-bearing. More recently, we have been using the Triple Tibial Osteotomy (TTO) and Tibial Wedge Osteotomy (TWO) (variations of these are called TPLO and TTA) techniques to provide stability to the joint in a dynamic way. We feel these newer tibial osteotomy techniques have given us an improved ability to control the abnormal cranial drawer movement (instability) of the stifle over the long term, especially in larger, boisterous or heavily muscled dogs. We feel this leads to better results in these dogs, leading to happier dogs with less knee joint pain. Either the TTO or TWO may be better suited for use in your dog.
This surgery removes a wedge of bone (determined from preoperative x-ray planning) from the tibia just below the stifle joint. The bone is repaired with a bone plate and screws.
This surgery removes a smaller wedge of bone and adds another cut in the bone to allow the attachment point of the patellar tendon to sit further forward – so the quadriceps plays a more active role in stabilising the joint.
Both these techniques allow us to avoid “tightening” the joint in a static sense with artificial materials. The forces acting through the joint are changed and in a sense “neutralised” so there is much less need for a cranial cruciate ligament.
We use a bone plate and screws (implants) to hold the bones together while they heal. Healing usually takes 6 to 8 weeks. The implants usually do not require removal. The skin incision we make is on the inner side of the stifle and tibia. Scarring is minimal and once the hair grows back, there is generally no obvious sign of the surgery.
CASTS, SPLINTS & BANDAGES may be used on your pet for any or all of the following reasons: to reduce pain, reduce swelling, mechanically protect from stresses which may compromise a surgery’s success or protect against licking and exposure to the environment. They have an important role and attention to their care will minimise the chance of problems.
ACTIVITY LEVEL: Unless advised otherwise, pets which have had a limb cast, splint or bandaged should be strictly confined to prevent problems. They should not be allowed to run, jump, play etc. It is usually best to provide a clean, dry secure area in which they are securely confined during most of the day and night (e.g., bathroom or laundry). There should be nothing in the area that they may climb or jump onto. Many dogs and most cats will require a cage for safe confinement. The vast majority of pets are perfectly happy being confined for the period of their convalescence. Certainly, when no-one is home this is especially important. It is best not to let them have the run of the house, even when people are home, as most pets will still jump up onto furniture or run to see who is at the door etc. Cats love nothing better than to climb up to “vantage points” in the house. When being taken outside for any reason dogs should be on a leash the whole time.
CARE FOR CASTS, SPLINTS & BANDAGES: Any time a dressing of any kind is placed on a pet’s leg or body, it requires we adjust the way we treat the pet to prevent problems arising. For example, access to water bowls may need to be supervised.
Never allow the dressing/cast to become wet. This is the biggest single cause of problems. Sources of moisture are wet grass, water bowls, saliva, urine etc. Wetness may cause serious problems within a few days, as bacteria begin to multiply in the dressing and on the skin. You can use a plastic bag over the dressing whenever pets go outside, but never leave it on for longer than 30 minutes. If a dressing/cast gets slightly wet, try carefully drying it with a hair dryer (depending on your pet’s temperament!) while being very careful not to overheat the skin beneath. If it has gotten too wet, it is best to return here to have a completely new clean dressing/cast applied.
Touch or squeeze the toes once or twice a day. Check for warmth, dryness and feeling. This is especially important for casts, which will not expand if the foot or leg should swell. Pick a time when the pet’s attention is distracted and touch or squeeze the toes in the dressing/cast. The normal response is for the pet to look at you or pull the leg back a little. If there is no response, try squeezing harder. If there is no feeling in the toes, the attention of a veterinarian should be sought immediately! Similarly, the toes should be looked at each day to see if there are any signs of swelling. Toes that are swollen indicate an underlying problem – seek advice – never cut off the bottom of a dressing/cast as any swelling is likely to worsen.
Keep an old clean sock over the dressing/cast. Socks keep a lot of dirt off while still allowing the dressing to “breathe”. Many dogs stop licking a dressing when a sock is placed over it. Don’t use waterproof / electrical / duct tape or plastic as a cover as they don’t allow the dressing to “breathe”.
Watch for irritations at the top of the dressing/cast. This may be caused by an allergic reaction to the sticky plaster, licking at the bandage, or a dressing which is rubbing. Call for advice if you notice this problem. With care, soft dressings will usually last for about 2 weeks, and casts should last for 6 to 8 weeks or more. Please note when your pet’s dressing needs to be changed or removed and arrange an appointment for this to be done. Sometimes, it’s best to drop your pet off early in the morning, then pick them up that evening.
PLEASE DON’T HESITATE TO CALL IF YOU HAVE ANY QUERIES
Dr Tim Caporn is a Fellow of the Australian & New Zealand College of Veterinary Scientists in Small Animal Surgery and is a registered specialist in small animal surgery. He has been offering specialist veterinary surgery services to the veterinarians of Western Australia for over a decade. The practice he established, Animal Surgical Referral Service has now been renamed Perth Animal Surgery and has relocated to a new facility at 305 Selby St, Osborne Park. This new facility allows an even higher quality of work and a greater range of services to be offered. Having a surgical specialist practice in the same building as advanced imaging facilities and an oncology practice provides the pet owners and veterinarians of Western Australia with unsurpassed diagnostic and therapeutic options in a client-centred private veterinary facility.
Karen joined Perth Animal Surgery in July 2010. She is a Registered Specialist in Small Animal Surgery and has been providing referral surgical services to Western Australia for 12 years. Her special interests are in soft tissue surgery. This includes oncology (surgery for cancer patients) all internal organ surgery (such as heart, lung, liver, kidney and intestines) reconstructive and spinal surgery. She is happy to work with any tail-wagging or purring patient though, whatever they require! She believes in the highest standard of compassionate, skilled care for all patients, whilst being a down to earth, approachable and personable clinician.