The most common cause of lameness in the hind leg of a dog is the partial or complete rupture of the cranial or anterior cruciate ligament. Typically large and giant breeds may present from as early as 3-5 years old while smaller dogs tend to develop problems later at 6-8 years of age. Whilst the actual rupture of the ligament is typically quite acute or sudden the underlying cause termed “Cruciate Disease” is a more chronic issue.

ANATOMY AND PHYSIOLOGY OF THE CANINE STIFLE JOINT

Anatomy and Physiology of the Canine Stifle Joint

The canine stifle joint is a complex joint made up of 3 main bones and 2 main ligaments surrounded by a sealed joint capsule, which retains joint fluid to lubricate the joint.

The femur (thigh bone) has a rounded base and sits on the normally flat surface of the tibia (shin bone). There are 2 small crescent shaped pieces of cartilage that sit either side of the tibia acting as cushions or shock absorbers in the knee joint. There are many ligaments within the knee joint but the 2 most critical are the anterior or cranial cruciate ligament (ACL) and the posterior or caudal cruciate ligament (PCL). As the name suggests they cross over inside the joint forming the major supporting structures internally. Running over these ligaments is the patellar or kneecap, which joins the quadriceps muscle via the patellar ligament to the front of the tibia.

The cranial cruciate ligament has 3 main functions.

  • It limits rotation of the tibia (shin bone equivalent) with respect to the femur (thigh bone)
  • Prevents hyperextension of the knee
  • Prevents forward movement of the tibia relative to the femur

An odd feature of the canine stifle is that the weight bearing surface (the tibial plateau) slopes backwards at an angle. Whenever a dog puts weight on their knee the cranial cruciate ligament must therefore take the strain. It’s like parking a car on a slope and relying on the handbrake to keep it there. If the cranial cruciate ligament fails, the tibia slides forwards and the joint capsule is stretched.

We call this motion tibial thrust or cranial drawer, and it hurts! It’s why when a cruciate ligament is ruptured a dog won’t put much weight on the leg.

WHY DOES THE LIGAMENT RUPTURE?

Why Does the Ligament Rupture?

Final rupture is typically due to a traumatic event. However the tendency to rupture, formally known as Cruciate Disease, is in many cases present from birth due to the anatomy of the stifle (knee) joint. The ligament degenerates progressively over time due to ongoing use and the unusual, and perhaps slightly illogical, anatomy of the canine stifle. The ligament may become stretched or partially torn and lameness may be only slight and intermittent, but a process of inflammation, or arthritis, is occurring in the joint at the same time. With continued use of the joint, the condition gradually gets worse until rupture occurs in the course of normal activity.

This degeneration over time is due to the steep angle of the tibia causing excessive strain on the ACL when preventing forward movement of the tibia with respect to the femur. This degeneration typically occurs more rapidly in larger breeds and/or obese dogs. The more sedentary lifestyle, including less formal activity and obesity hasten this degeneration of the ACL through lack of supporting musculature. Most studies show that larger breed, younger, more active dogs are particularly at risk simply due to the higher weight and level of use of the ACL over time. This progressive degeneration explains why the traumatic event that causes final rupture can often seem quite minor. This also explains why 35-40% of dogs will rupture their other cruciate within 1-2 years.

Dogs’ knees move in very much the same way as human knees, but the top of the tibia (the tibial plateau) slopes backwards in the dog’s knee putting stress on the cruciate ligament and can cause the ligament to rupture with repeated low grade stress. Humans have a perfectly level tibial plateau, which explains why they are not prone to repeated low-level injury. Stepping down off the bed or a small jump can be all it takes to break the ligament. The lameness may be acute but have features of more chronic joint disease or the lameness may simply be a more gradual/chronic problem.

Dogs that rupture one cruciate ligament frequently rupture the other one within a year’s time. An owner should be prepared for another surgery in this time frame.

DIAGNOSIS

Diagnosis

Most experienced veterinarians will be able to make a presumptive diagnosis on careful clinical examination of your dog. Confirmation of the diagnosis involves several steps and it is important these are completed to ensure the correct diagnosis is made.

The diagnosis is usually made on physical examination. The stifle is manipulated to detect evidence of pain, swelling or instability. An anterior draw sign is diagnostic for a ruptured CCL. A tibial compression test is also performed in relaxed conscious patients to further confirm cruciate ligament deficiency. If patients are anxious this will be done prior to the surgery when they are first anaesthetised for radiographs.

A common test performed on first evaluation is the “sit test”. Most dogs will sit with both legs folded comfortably under their body. A dog with a ruptured ACL with often sit with the affected rear leg extended out from under the body. These dogs will also tend to lean forward placing more weight through the front legs as they move to a standing position.

The patient will usually have a history of holding the affected leg up, or reducing weight bearing through this leg by toe touching only when walking. You may also notice when your dog is walking, the tibia (shin bone) rotates internally due to reduced muscle mass in the upper part of the leg following the injury. In chronic long term cases there can be a swelling on the inside of the knee known as a medial buttress. This swelling is due to scar tissue and changes to the bone to counteract the abnormal pressure through the ACL over an extended period of time.

Presentation of a dog with a ruptured ACL can be an acute or sudden injury or a long term chronic non resolving lameness not responding to any significant degree to routine anti-inflammatory and pain relief medications. Lighter patients (<15kg) may resolve their lameness to varying degrees over 1-5 months however will be certain to experience arthritis in the knee later in life. Patients weighing over 15kg will in almost all cases never return to normal pre-injury levels of activity without surgical intervention. In cases of partial rupture, there may be some improvement for 2-6 weeks followed by recurring intermittent lameness, which never resolves completely. This recurrent lameness is indicative of the development and progression of degenerative joint disease or arthritis. It is important to realise that even with surgery and stabilisation of the knee there will always be some degree of arthritis. However the surgical repair and stabilisation minimises the development of arthritis usually to a very manageable level. Knees that are not surgically repaired may develop such severe arthritis later in life that they are non-functional for normal daily activities.

Rupture of the ACL can be partial or complete. Complete rupture with result in complete lameness, with your dog unable to bear weight on the affected leg. The injury is typically very painful initially but settles to some degree within the first 24-48 hours. However a full rupture will not allow significant weight bearing without surgical repair. A partial rupture may appear initially with a significant lameness, which will improve to some degree over days to weeks but if significant enough will never be able to bear full weight properly without surgical repair. Chronic partial ruptures can be harder to identify with dogs being initially a little sore when they first wake up but ok during exercise once they warm up but stiff again when they cool down. A typical history of a partial rupture or strain of the ACL would be an ongoing intermittent lameness that does not get obviously worse but also does not improve despite rest and anti-inflammatories. Additionally there may be quadriceps muscle wasting, knee pain and reduced ROM (range of movement).

SURGERY VERSUS MEDICAL MANAGEMENT

Surgery Versus Medical Management

Dogs under 10kg with ruptured cruciates may improve to an acceptable level without surgery. In particularly aged patients, surgery is less desirable usually for various other health reasons. These patients are on restricted activity for 2-4 weeks but if a limp remains or recurs intermittently, surgery is the only option for a complete recovery. Dogs over 10kg nearly always require surgery to heal. Unfortunately, most dogs will eventually require surgery to correct this painful injury.

SURGICAL REPAIR OF RUPTURED ACL

Surgical Repair of Ruptured ACL

The aim of surgical repair is to

  • Stabilise the joint
  • Provide an outcome of pain free function to pre-injury levels wherever possible
  • Limit the development of future arthritis (degenerative joint disease)

There are several ways this can be achieved. Selection of technique depends on what is best for your dog’s size, age and condition.

Traditional cruciate surgery techniques 

These procedures aim to replace the function of the cruciate and passively stabilize the stifle joint. These involve placing a synthetic ligament on the outside of the joint capsule (“extra-capsular”) to replicate the role of the missing cruciate ligament. This procedure essentially replaces the old ligament without realigning the joint. This is often termed a bandaid procedure, as there is still a risk of premature repeat rupture of the new ligament and subsequent instability. This procedure should only be performed in dogs under 10kg.There are several specific techniques such as De Angelis and ISO toggle techniques.

Conventional techniques

Aim to produce dynamic stability of the stifle, using the muscles to stabilize the joint, essentially replicating the level tibial surface of the human stifle. We change the way the joint works so the cruciate ligament is no longer required to stabilise the joint. Various techniques described as TPLOs (Tibial Plateau Leveling Ostectomies) and TTAs (Tibial Tuberosity Advancement) are available. These are generally indicated in larger patients as the only option for surgical repair. They are also the preferred option for all patients as the outcome is far superior to the extra-capsular procedures.

At TRVC we offer both a DeAngelis (extra-capsular repair) and a TTA (Tibial Tuberosity Advancement).

DeAngelis/Extra-Capsular Repair (Lateral Suture)

The joint is stabilised by 2 appropriately sized monofilament or nylon type suture placed around the outside of the joint but under the skin. This suture mimics the path of the ACL. We think of this procedure as a bandaid as it fails to address the underlying issue of tibial thrust. Effective recovery for this procedure relies on the body creating fibrous or scar tissue across and around the knee joint. It is critical this scar tissue forms before the suture is stretched. So in essence there is a race between the body forming scar tissue and the suture stretching out. For smaller dogs and cats we usually win this race but larger dogs will often stretch the repair before enough scar tissue forms to stabilise the joint. Research has shown the suture will break completely anywhere between 2 and 12 months after surgery depending on the size of the dog and the level of activity.

Even though there have been many patients with very good outcomes after external capsular repair, the number of dogs that do not stabilise adequately is too high to consider it a reliable treatment for this injury. Our preferred surgical option for the repair of a ruptured ACL is the Tibial Transposition Advancement procedure. This is the only option for dogs 15kg and over but also the preferred option for all our patients based on minimising arthritis later in life, quicker recovery and most importantly they can’t rupture it again.

TTA and TPLO – Overview 

TPLO (Tibial Plateau Levelling Osteotomy) and TTA (Tibial Tuberosity Advancement) are two biomechanically similar surgical techniques used to treat medium and large dogs (more than 15-20kg) with a torn ACL. Both the TPLO and TTA create stability within the dog stifle by altering the forces in the knee. They both involve making a surgical cut in the tibia (shin bone) and using implants to hold the bone in place while it heals in a new position. The new position allows knee stability to be provided by other knee structures, without the need to create a new ACL or repair the old one. The TTA procedure is essentially a modified version of the TPLO procedure, using a different location for the bone cut that is less invasive. Both of these procedures have an advantage over external capsular repair because they neutralise Tibial Thrust. This means that during normal weight bearing the femur is not being forced off of the back of the tibia. Both TTA and TPLO are great procedures that have a very high rate of success and will in >95% of cases return the patient to normal or near-normal function and once fully recovered there is no chance of repeat failure.

At Toorak Rd Veterinary Clinic Dr Wilson prefers the TTA because there is a quicker return to normal activity following surgery, fewer complications, and a less invasive bone cut (osteotomy). The recovery from this procedure is exceptional with most dogs, big and small, walking 1-2km by 2 weeks post-operative.

The TTA uses titanium implants, which carry less risk of infection and rejection and offer superior biocompatibility over the stainless steel implants used in TPLO. Also, because TTA is a quicker procedure to perform, there is less time spent in the operating room, which means lower chance for infection or anaesthesia-related complications.

In the TTA, the osteotomy (bone cut) is made in the tibial tuberosity, which is not a weight bearing part of the leg. This appears to make TTA patients more comfortable earlier following surgery compared to the osteotomy for the TPLO made in the weight bearing portion of the bone. The TTA has the added advantage of being modified to treat patella luxation if required, occasionally seen with torn ACL in dogs.

THEORY BEHIND TTA PROCEDURE

Theory Behind TTA Procedure

The TTA or Tibial Tuberosity Advancement Procedure is based on the research that the patellar ligament can stabilise the joint if it is at a 90-degree angle to the tibial plateau.

During weight bearing, the femur slides down the tibial plateau caudally. The anterior cruciate ligament (ACL) acts against this downward force. The surgery changes the biomechanics of the stifle joint (redirecting the strong muscular forces of the muscles on the front of the thigh) so that stability is created without applying an artificial physical restraint across the joint. This technique offers more advantages than other surgical techniques by being less invasive and faster to perform. The patients undergoing this procedure do not need to wear any form of bandage when going home. By advancing the tibial tuberosity in an ACL deficient knee, the patellar ligament is adjusted perpendicular to the tibial plateau. This eliminates the tendency of the femur to move downward over the sloped plateau.

The patellar ligament is one of the toughest ligaments in the body, and it is completely controlled by one of the biggest muscles in the body, the quadriceps muscle on the front of the leg. Dogs having a steeper slope are more predisposed to rupturing the ACL. The TTA aims to correct for this slope by adjusting the angle between the tibial plateau and the patellar ligament. By advancing the tibial tuberosity, we can overcome the abnormal front to back motion called tibial thrust, and also tend to overcome the tendency for pivot shift or rotation of the tibia relative to the femur.  Current thought is that this procedure leads to less arthritic change in the joint.  This procedure can be successfully done on any size dog, and is currently the treatment of choice by many surgeons.

TTA Implants on Bone Model
THE DAY OF SURGERY

The Day of Surgery

Please do not feed any food after 8pm the night before your pet’s procedure. Water can be provided up until the morning of the surgery. If time allows, a short walk to allow your dog to defaecate is ideal. Drop off for surgery is between 8am and 9am in the morning. If you have a surgical admission appointment please ensure you arrive at this time so we are able to admit your dog immediately and can ensure your day runs to schedule.

Our surgical nurse will admit your dog into the surgical ward. On arrival at Toorak Rd your dog will have a small amount of blood taken and run on our in-house blood machines to ensure they are fit for general anaesthetic. If your dog has had bloods taken recently we may not need to perform further testing so it is important to bring these results with you. All blood testing done at Toorak Rd remains on file so if your dog had bloods done here we will review them directly.

Once blood results are through and clear, your dog will have a pre-operative exam prior to anaesthesia. A small injection or premedication is given under the skin containing a mild sedative and pain relief. This helps to settle your dog and get pain relief into their system before the surgery begins. This also makes a big difference post-operatively for a smoother recovery.

When your dog is settled, an intravenous line is placed in one of the front legs. This allows us to deliver medications directly into the blood stream during the procedure and also provides your dog with intravenous fluids including a 3 part constant rate infusion (CRI) of pain relief. This CRI continues after surgery and overnight whilst they are in hospital. We find a pain free dog to be a happy and relaxed patient during recovery.

The induction anaesthetic agent is given via the intravenous line and your dog goes to sleep. An endotracheal tube is placed down the trachea and they are placed on to a gas anaesthetic (isofluorane carried by oxygen). This gives us very fine control over your dog’s anaesthetic depth. We have a dedicated surgical nurse throughout the procedure and during recovery whose only concern is making sure your dog has a safe anaesthetic and smooth recovery. Other tasks like answering phones and handling other animals are left to our floating nurse and receptionist.

Radiographs are taken of the affected leg in 2 views prior to surgery. This allows us to assess for other bone diseases and determine whether arthritis has started to develop, which may affect the rate of recovery post-operatively. It is not possible to see the ruptured cruciate ligament on radiographs (humans have MRIs) but we can see swelling of the joint and confirm by physical examination on the anesthetised patient that the diagnosis is correct. The radiographs are also important to measure accurately the implants required for the procedure. Each dog is different so the x-rays allow for the individual planning of implants prior to surgery. While the opportunity is there, we will often radiograph the opposite leg if there is any suspicion of early cruciate disease.

Your dog will stay in the clinic overnight on a drip, which provides continuous pain relief in 3 different forms. This helps provide a more gradual adjustment to the newly operated leg. The pain relief also provides a low level sedation so the initial stress post operatively is minimised. On rare occasions if a patient is especially distressed being away from their family we will send them home on the day of surgery. All our clients have Dr Wilson’s after hours mobile phone number (0423 401 488 – Please note this service does not receive text messages). Dr Wilson is available until 11pm.

THE SURGERY

The Surgery

The first step of the surgical procedure is to check inside the knee joint (arthrotomy). This allows us to see directly the level of arthritis and check the integrity and health of the internal structures. Any residual fragments of the cruciate ligament are also removed as they can contain pain fibres that are still active so painful during ambulation (walking). We also assess the crescent shaped cartilage cushions (meniscus) at the back of the knee joint using a meniscal probe. These are often damaged when the ACL is ruptured. We remove any damaged part of the meniscus during the arthrotomy.

The TTA procedure is performed by making a cut (osteotomy) in the top part of the tibia (shin bone) and repositioning it. This changes the biomechanics of the stifle joint so that it is more stable in the absence of an intact cruciate ligament. The newly positioned tibia is then held in place by a specially designed titanium tension band plate, titanium bone spacer cage and screws so that the bone can heal. The opening between the tuberosity and the tibia (the osteotomy) is packed with bone graft from inside the tibia that will provide living bone cells to help the space fill with bone. Bone will grow in and slowly fill the gap, providing even more stability over time. In our hands, we see dogs being able to bear weight on their repaired knee within 24-48hours.

The TTA can be performed on patients of any size. Dr Diana Wilson has successfully operated on dogs ranging from 8 to 80kg.

Post-operative radiographs are performed to confirm accurate placing of TTA implants. These will be compared to the 8 week post-op radiographs to ensure adequate bone healing has been achieved.

Titanium TTA Implants
Post TTA Radiograph
Post TTA Radiograph
COMPLICATIONS

Complications

With any orthopaedic procedure there is always the risk of complications. At TRVC we see very few complications. Complications including infections, destabilisation or loosening of implants and fractures at the site of implants can be seen with orthopaedic procedures.

GOING HOME

Going Home

It is important your pet is confined to a small area or room for the first 2 weeks. For small pets this may be a modified playpen or dog crate while for larger pets consider using the laundry or section of the home (it is critical the surface is non-slip) which can be sectioned off. We particularly want to avoid access to hallways when the front door bell rings!

Non-slip flooring is crucial and will reduce the chance of accidental falling, which may cause the surgery and implants to fail. Surgical wounds need to be kept clean and dry at all times. Provide clean, padded bedding for your dog to lie on. Block off access to any stairs and under no circumstances allow your dog to jump. This is extremely important – so no jumping to greet, beg or play and no jumping off beds/furniture.

Your dog should have a warm and comfortable place to sleep that allows them to stretch out if they wish. Preferably your dog would sleep inside for the first few weeks post-operatively especially if it is winter as a cold leg is usually a sore leg, which does not help a smooth recovery.

Depending on the personality of your dog you may need to take some time off work. Your dog needs to be happy being settled in a small section of the house for the first 2 weeks. Having said that controlled lead walking starts 2-3 days post-surgery so they will be exercised and stimulated to some degree.

Medications

Post operatively your dog will be given 2 types of pain relief to take home.

  1. Metacam (meloxicam) provides moderate pain relief sand anti-inflammatory effects. It is a non-steroidal anti-inflammatory drug given in a liquid form once daily with or after food. This is started in hospital on the morning after surgery.
  2. Tramadol is a stronger narcotic like drug providing only pain relief given in a tablet form. Tramadol has a wide dose range, which means we can adjust your dogs dose according to their individual requirements. Typically it will start around midday on the day your dog goes home. Tramadol is typically required every 8-12 hours for the first 2-5 days depending on the individual. if you feel your pet is uncomfortable please contact us on 9809 2700 and we can advise you as to how much the dose or frequency of their pain relief can be increased.

Tramadol has the side effect of constipation, which we counteract by providing you with psyllium husks to be given with their food. The psyllium husks have basically no taste, just a texture so are easily mixed in with a soft food.

Your dog will receive intravenous antibiotics (Cephazolin) during the procedure and start on oral antibiotics (Cephalexin) in hospital the morning after surgery to be given twice daily till the course is completed (1 week).

Skin stitches are intradermal and completely dissolvable which means there are no visible stitches on the outside of the wound. We find this wound closure method to be much more comfortable and provides more rapid and effective healing for your dog and there are no stitches to chew out! However dogs may still lick the wound to a point where it can become very red and irritated and potentially break down. To prevent this we use a topical bitterant DMP (Di Methyl Phthalate). DMP tastes terrible and when a few drops are applied directly to and immediately around the surgical wound it is a very effective deterrent. DMP is usually only required 2-3 times daily for 2-3. Occasionally very persistent lickers may require an Elizabethan collar.

All our TTA patients receive a 4 week course of Synovan (Poly Sulphated Glycosaminoglycans) injections starting weekly from 1 week post-op. Synovan is a wonderful product that assists in the repair of the joint and help to minimise arthritis going forward. After the initial course of 4 weekly injections your dog will have 3 monthly injections to help minimise arthritis in the knee going forward.

It is important to understand your dog’s knee will develop arthritis as they age. Any joint in the body that is operated on will have some degree of arthritis, but the aim is to minimise this with minimal side effects on the rest of the body. Synovan injections have no significant side effects when used long term.

We do not routinely bandage the leg after surgery. Swelling post-operatively is minimal and a bandage adds excess weight to the operated limb. For this reason we typically find a bandage more of a hindrance than advantage during the initial stages of recovery.

REHABILITATION PROGRAM AT HOME

Rehabilitation Program At Home

On returning home the key is controlled early exercise.

The following guidelines have many benefits and should be followed as closely as possible to allow a complete and uneventful recovery from surgery.

The aims of the exercises are to:

  • Speed the recovery of the operated leg
  • Decrease pain and enhance healing of the operated tissues
  • Prevent further disuse muscle atrophy
  • Restore a normal range of motion of the stifle joint
  • Decrease the possibility of compensatory issues (excessive strain/weight bearing on the other leg) during recovery

It is important to remember all dogs will recover at different speeds. Dr Wilson will assess your dog at each review and discuss with you their progress and rehabilitation program. At any time during your dog’s recovery if you are unsure of anything please call the clinic on 03 9809 2700.

In past years many veterinarians have been hesitant to allow early exercise on an operated leg. However if there is one thing we can learn from human medicine, it is that the sooner the patient is up and about the quicker the recovery. Having said that dogs in general recover much more quickly than humans after any procedure. There is one consideration we should keep in mind – that if a dog’s leg doesn’t hurt it will use it and premature overuse of the operated leg can cause critical damage to the healing process. The true purpose of pain is to remind the body that there is still healing going on. Keeping that in mind within reason a small amount of discomfort as opposed to pain can assist in grading exercise to an appropriate level.

How to Perform Massage

With your dog lying in a comfortable location on their side gently begin by stroking from head to tail to initiate relaxation. Once you feel your dog is relaxed run your hand down each limb slowly 4 times. This should be done at the beginning and end of each session. From day 7 a heat pack on the operated leg prior to massage can also be beneficial. Once your dog is relaxed you can begin firmer massage with some focus on the operated limb and opposite hind limb as the most affected areas of the body.

The Benefits Of Massage

  • Helps to maintain a positive relationship with your dog during the recovery period
  • Helps to relieve anxiety and stress
  • Can reduce pain and discomfort around the wound
  • Helps mobilise and reduce localised swelling around the wound
  • Helps to maintain muscle tone and minimise muscle tension

After the first week a heat pack can be applied to the leg especially prior to exercise 2-3 times per day for 10-20 minutes. Again make sure it is a comfortable temperature and conforms to your dogs’ leg, typically again wrapped in a hand towel or similar. It is ideal to use the heat pack prior to Passive Range Of Motion exercises.

How to Perform Passive Range Of Motion Exercises

Although this can be done standing the ideal position is the same as for massage – lying on their side in a comfortable location. It is very important to be gentle and not cause any pain, distress or discomfort during these exercises. Support the limb both above and below the knee joint and slowly move the limb in a controlled and steady manner. Move the operated leg from a fully extended position slowly towards a fully flexed position as far as your dog is comfortable. This position should be held for 2-3 seconds then slowly released to full extension and hold again 2-3 seconds. Ideally aim to complete 10-15 repetitions 2-3 times per day building up as your dog is comfortable.

Benefits of PROM

  • Improves joint range of motion in early stages of recovery
  • Prevents joint contracture and associated muscle tension
  • Improves healing of scar tissues by preventing soft tissue adhesions
  • Enhances joint fluid production and subsequently joint lubrication
POST-OPERATIVE RECOVERY
THE FIRST 2 WEEKS

First 2 Weeks

The first few days after your dog comes home the pain will be maximal. This should be managed very effectively by the combination of Meloxicam and Tramadol as described. If you have any concerns regarding the level of pain relief for your dog please contact the clinic immediately on 9809 2700.

The first 48 hours after surgery your dog should rest and the only exercise should be for short toilet walks on the lead. Be diligent with taking your dog out to the toilet regularly, due to discomfort they may not let you know when they need to go and hold on till it’s too late!

2-3 days after surgery your dog should start with short, controlled leash walks for 5 minutes 2-3 times per day. This should increase every 2 days provided the leg is down on the ground and your dog seems comfortable. Many dogs will be walking 1-2km at 2 weeks post-op. It is critical that you walk slow enough that your dog is forced to bear weight on the operated leg. It can be helpful to walk on uneven surfaces (eg nature strip, sand, tan bark) to encourage the use of the leg, as this will force them to balance more effectively.

If your dog is comfortable an ice pack may be used for the first 5-7 days 2-3 times per day for 10-20 minutes. This will help significantly with post-operative swelling. The ice pack should be conforming and wrapped in a hand towel or similar to avoid direct contact with the leg.

Although not critical, gentle massage of the muscles of the operated leg and very gently along either side of the wound may help with wound healing and comfort. Although some dogs may be too anxious for this to be done effectively others may find it quite soothing as the wound can be a little itchy and they cannot touch it gently enough themselves. If massage is going to be used on a regular basis it is ideal to massage more than just the operated leg as many of the muscles will be over compensating during recovery and will benefit from massage in the same way humans do.

2-4 WEEKS POST-OP

2-4 Weeks Post-Op

Slowly increasing controlled leash walking will continue. Typically dogs will reach their normal pre-injury walk around week 4 although some may take longer if there are underlying issues such as significant pre-existing arthritis and muscle atrophy due to delayed surgical intervention.

Figure 8 walking exercises can also begin at week 4. Imagine you are walking a line of figure 8 initially quite large and over time becoming smaller, with a tighter circle. The aim of figure 8 is to increase muscle strength especially of the smaller supportive muscle groups as they adjust around the circles.

PROM exercises and wound massage can be continued if still deemed beneficial at this stage.

At this stage sit-to-stand exercises can be added in if your dog is comfortable. The aim is for your dog to sit with both stifles tucked under the body symmetrically each side. Some dogs may take longer before this is comfortable, as it requires nearly full flexion of the stifle. Begin with 5-7 repetitions 2-3 times per day. This exercise is purely to increase passive strength of the quadriceps muscles.

After week 4 heat packs are no longer thought to be beneficial but if a heat pack seems to help your dog to exercise more comfortably there is no harm in continuing prior to exercising.

5-8 WEEKS POST-OP

5-8 Weeks Post-Op

Heat, PROM and massage are no longer required.

Continue controlled leash walking, figure-8’s and sit-to-stand exercises. At this stage introduce hill walking with slow increase in length of hill and to some extent steepness.

Stairs can also be included as a formal exercise with repetition increasing over time. Sometimes dogs have been using stairs out of necessity from as early as week 2.

Typically, off lead exercise will begin at 6-8 weeks post surgery depending on your dogs’ recovery. This will be discussed in detail at your dog’s post- operative reviews depending on their individual recovery progress.

Off lead work should begin in a quiet, controlled situation. Dogs that are not easily controlled off lead will need to wait until the 3 month mark. However if owners are comfortable to jog with their dog this is an excellent start for off lead work especially for excitable dogs. Avoid other dogs as rough and tumble is not advised until 12 weeks post-operative depending on Dr Wilson’s recommendation.

WOUND CARE

Wound Care

Please look at the incision once daily. It should be dry and slightly red along the margins. There may be slight swelling or thickening of the edges. Over several days, it should lose redness and swelling. Some bruising is quite normal and should resolve in 5-7 days.

We almost always use internal also known as intradermal sutures with our surgical procedures. This means less irritation post-operatively for your pet and no stitches to be removed. It also means we rarely use Elizabethan collars, which are often quite awkward and restrictive for both pets and owners following major surgery. We typically find a topical bitterant is more than adequate to deter licking. These usually only needs to be applied 2-4 times a day in the first 2-5 days post-operatively depending on how determined you patient is!

WHEN TO CONTACT THE CLINIC

When to Contact the Clinic

  • If your pet seems unusually uncomfortable
  • If there is any redness or swelling of the wound
  • If your pet is licking or chewing at the wound
  • If you are worried at all about your pet

It is important to understand that it is quite normal for your dog to “overdo it” at some time in the first 12 months post surgery. They may become quite lame for 24-48 hours but quickly return to near normal then back on track within 3-4 days. If you have pain relief/anti-inflammatory medication remaining this can be given for 1-2 days and provided the lameness is near normal within 24-48 hours there should be no major issues. However if the lameness continues, becomes more severe or you are concerned, please bring your dog in for review.

Many people are not sure whether their pet is acting normally, and are not sure whether to ring or are embarrassed to ask us. Please, if you are at all concerned don’t hesitate to call on 9809 2700.

Dr Wilson also has an after hours number (0423 401 488) till 11pm which you can contact her on for emergencies or certainly urgent concerns after a major procedure. Please do not text this number – phone calls only, as any text messages will not be received.

POST-OPERATIVE CHECKS

We have 6 scheduled follow-up appointments but if you need any additional reviews in the first 3 months post-op there is no extra charge so please come and see us if you are worried about your dog’s recovery. Please avoid any bathing or swimming activity prior to the 1st check.

 

1 week                  Synovan Injection number 1

2 weeks                Synovan Injection number 2

3 weeks               Synovan Injection number 3

4 weeks                Synovan Injection number 4

8 weeks               Post Op Radiographs

4 months             3 Monthly Synovan Booster

LONG TERM RECOVERY
The prognosis for dogs treated with a TTA to correct a ruptured cranial cruciate ligament is good to excellent.The majority of dogs return to a normal gait, level of activity, and endurance. Following the 12 week recovery period, there are no recommended limitations to their lifestyle. It can take up to 4-6 months for maximal improvement and return to pre-injury muscle strength can take up to 12 months. Professional physical therapy services can speed recovery dramatically.

Diets and Supplements

It is critical that your dog maintains ideal body weight. This helps reduce wear and tear on both the operated knee and other joints so minimising arthritis going forward

There are 3 features to help monitor appropriate body condition.

  • You should be able to feel the ribs easily but not see them
  • Your dog should have an “hour glass” type figure showing a waist when viewed from above looking down
  • Your pet should have a tucked up belly when viewed from the side in the same way you might see for a greyhound although not to the same extent for more solid breeds such as Labradors or Retrievers.

We would recommend changing the dry food component of their diet to either Hills J/D (Joint Diet) or Royal Canin Mobility. These diets work on the research showing high levels of omega 3 and 6 fatty acids result in natural anti-inflammatory effects. They also have chondroitin and glucosamine, which help support the growth of new cartilage in the joints. We stock both of these products at TRVC however if you need it urgently please call ahead as we may run out on some days!

 

OUR SERVICE TO YOU

Our Service To You

For all our TTA procedures there are typically 4-6 revisit consults required. However there is no additional charge for extra post-operative consults within the 3 months following the procedure. We want to be certain you are able to bring your dog in with any concerns you may have during their recovery.

The cost of the procedure also includes the course of 4 Synovan injections and the post-operative radiographs taken under sedation at 8 weeks post-op.

We also cover any costs for surgery should further surgical intervention be required due to complications.

For new clients we offer a no charge pre-surgical consultation for TTA procedures. If your dog does not need surgery or you are not comfortable to go ahead with surgery there is no obligation to go further.

DISCLAIMER

Disclaimer

The information described above is directly relevant for patients of TRVC. The clinic does not bear any responsibility for clients from other clinics using these guidelines for their dogs.

FREQUENTLY ASKED QUESTIONS

Frequently Asked Questions

WHY IS THE DAMAGED MENISCUS REMOVED AND NOT REPAIRED?

Why is the damaged meniscus removed and not repaired?

Pets with meniscal damage may have an audible clicking sound when they walk or when the knee is examined, but for a definitive diagnosis the menisci must actually be inspected during surgery. It is difficult to access the menisci and thus repairing a tear in the meniscus is problematic; furthermore, poor blood supply to the menisci also makes good healing less likely. For these reasons, removal of the damaged portion of the meniscus is the most common surgical choice.

WHY DOES MY DOG NEED SURGERY?

Why does my dog need surgery?

Unfortunately, if your dog ruptures the Cranial Cruciate Ligament, surgery is the only real option.  When the ligament is torn, there is a shearing force that results when your dog tries to bear weight on the leg. This shearing force makes the femur slide backwards on the surface of the tibial plateau.  This abnormal movement sets up excessive wear and tear on the cartilage surface, which induces further arthritic change in the joint. Additionally, this abnormal motion frequently damages the cartilage pads known as the menisci. Damaged menisci also lead to further arthritic change.  Many dogs develop such severe arthritis and bone spurring (osteophytes) that they have constant pain and an associated restricted range of joint motion.

Osteophytes and other arthritic changes are evident as soon as 1 to 3 weeks after the rupture in some patients. This kind of joint disease is substantially more difficult for a large breed dog to bear, though all dogs will ultimately show degenerative changes. Typically, after several weeks from the time of an acute injury, the dog may appear to improve as they adjust to the pain but rarely return to an acceptable level of function long term.

WHY DO DIFFERENT SURGEONS RECOMMEND DIFFERENT PROCEDURES?

Why do different surgeons recommend different procedures?

For many years, various surgeons have proposed different procedures to repair a ruptured cranial cruciate ligament. As the researchers have analysed follow up data, it has been shown that certain procedures are not as good as they initially were thought to be. This is a normal event in medicine (both human and veterinary).  This does not mean that the surgeries proposed 20 years ago, or even 5 years ago, were wrong. It simply means that as good surgeons, we are constantly striving to offer the best alternatives now.

IS THE TTA PROCEDURE ONLY FOR LARGE BREED DOGS?

Is the TTA procedure only for large breed dogs?

The TTA procedure can be successfully performed on almost any size dog.  Implants are made for dogs as small as 5kg to dogs over 80kg.

HOW COMMON IS CRUCIATE LIGAMENT INJURY?

How Common Is Cruciate Ligament Injury?

It is…

  • The number one cause of chronic hind limb lameness
  • The most common orthopaedic surgery in dogs
  • The leading cause of stifle arthritis

Non-surgical therapy does not address the biomechanical instability in the stifle. The goals of surgery are to relieve pain, restore function and minimise the rate of progression and ultimate extent of osteoarthritis by stabilising the joint.

IS OTHER JOINT DAMAGE COMMON?

Is other joint damage common?

Once ruptured the stifle becomes unstable. The joint becomes more acutely inflamed and painful. The instability also leads to damage of the medial meniscus – a C shaped piece of shock absorbing cartilage located inside the joint. This is very commonly damaged and is a source of pain. We often feel a “click” in the stifle of dogs with meniscal damage. If left unmanaged the stifle joint becomes thickened and chronically painful. The leg muscles may waste due to disuse.

WILL MY DOG RUPTURE THE OTHER LEG?

Will my dog rupture the other leg?

35-40% of dogs rupture the ACL of the opposite leg within 1-2 years of the first. The best way to reduce the odds of this happening is to perform the TTA as soon as possible to give your dog a “good” leg to use so minimising strain on the presently non-ruptured leg.

MY FRIEND'S DOG DIDN'T HAVE SURGERY AND NOW WALKS WITH A LIMP DESPITE IMPROVING INITIALLY

My friend’s dog didn’t have surgery and now walks with a limp despite improving initially

After approximately 1 year following the injury the knee joint capsule and the tissue surrounding the joint will suffer from excessive fibrosis in an attempt by the body to stabilise the joint. Extra scar tissue will form in response to the chronic inflammation of the joint (arthritis). The mobility of the knee will be affected and your pet will be able to walk, but generally with a severe limp and will not be able to run, jump or play as before the injury. Unfortunately these patients gain weight due to inactivity and eventually injure the opposite knee a few months to years later.

IS THE POSTOPERATIVE PERIOD MORE PAINFUL COMPARED TO OTHER PROCEDURES LIKE TPLO?

Is the postoperative period more painful compared to other procedures like a TPLO?

It is less painful, as the TTA is performed on a non-weight bearing portion of the bone; all patients are amazingly comfortable in a short period of time. We find that especially with the first night in hospital maintained on a constant rate infusion intravenous line of pain relief they are mostly toe touching day 1 on their way out the door of the clinic.

WILL MY DOG RETURN TO NORMAL ACTIVITY?

Will my dog return to normal activity?

Return to normal activity is almost always achieved. Unrestricted activity can usually resume following confirmation of bone healing at 16 weeks, however improvement in muscular strength will continue for the next 6-12 months. Muscle atrophy associated with loss of function on the affected knee may lead to a longer recovery time if surgery is delayed after lameness develops.

ARE THERE ANY COMPLICATIONS WITH TTA?

Are there any complications with TTA?

TTA is a complex orthopaedic procedure requiring general anaesthesia and exposure of the knee joint and bone. Wound bleeding, swelling and infection may occur as with any orthopaedic procedure but are uncommon and temporary. Movement or loosening of the bone or metal implants is uncommon but may result from excessive early post-operative activity. This complication may require re-operation by a specialist and incur further costs. We believe home care is just as important as the surgery in ensuring your dog has no complications.

Complications such as infection, suture reaction or reaction to the artificial ligament, tearing of the artificial ligament, or future meniscal tearing are possible. Major complications, those requiring additional surgery, are rare. As long as the activity restrictions are adhered to, the chance that additional surgery will be needed is low.

CAN THE LEG BE RE-INJURED FOLLOWING SURGERY?

Can the leg be re-injured following surgery?

After the healing is complete, it is rare for problems to develop. In fact, tibial tuberosity advancement surgery is occasionally performed when other methods of repair have failed to return dogs to normal use of the leg(s).