The cruciate ligaments are two ligaments that run through the stifle (knee) joint forming an ‘X’ when the stifle is viewed from the side. They are called the cranial (anterior) cruciate (CCL or ACL) and the caudal/posterior cruciate ligament.

Injury

Partial or complete rupture of the cranial (anterior) cruciate ligament is a very common injury in dogs and also occurs in cats. Rupture causes instability of the stifle (knee) joints. This also causes acute pain and over time leads to degenerative joint disease or osteoarthritis. Quite commonly, there is also a tearing of the meniscus (cartilage) within the joint which can occur either at the time of rupture, or some time into the future, especially if not repaired.

Diagnosis

Diagnosis may be possible at your pets initial consultation. However some patients are sore and nervous and tense the muscles of the leg, making it impossible to feel the instability in the joint. For these patients sedation is needed to allow our veterinarian to determine whether cruciate injury has occurred. This is very important because if cruciate injury is suspected, injury cannot be ruled out unless assessed under sedation.

Treatment

Without surgical repair, dogs with ACL lameness will develop degeneration and arthritis within the joint over time, due to the femur and the tibia shearing against each other with each step. Surgery is therefore recommended for any dog with ACL damage.

There are two main techniques for repairing cruciate injury:

• Joint stabilisation techniques
• Joint levelling techniques

SAH is one of the few general practices who offer four different techniques when it comes to cranial cruciate repair. Two stabilisation and two levelling procedures. Before going into greater detail of these four techniques, it is important to understand the anatomy of the knee, which will help explain which of the techniques is best suited to your dog. A human knee is a horizontal level joint. Hence when a human ruptures their cruciate ligament (a very common injury), unless the patient is active (I.e: a sportsperson), it is not necessarily vital to stabilise the joint because every time they take a step, there is no shearing force causing excessive movement of the joint. For athletes however, repair is most important.

A dog and cats knee is not a horizontal level joint. The top of the tibial bone is angled, usually between 15 to 40 degrees. If the cranial cruciate is ruptured, this means that every time they take a simple step, there is a shearing force that slides the femoral bone down in relation to the top of the tibial bone that forms the joint. It’s this shearing force that causes ongoing damage, pain and arthritic change over time.

Hence for our pets, when rupturing their cruciate ligament, we need to either stabilise the joint or turn the sloping angle into a horizontal angle like a human joint.

This is the basis of the two types of techniques. We can now describe these in more detail:

1) Joint stabilisation techniques:

With stabilisation techniques we aim to replicate the cruciate using a prosthesis ligature which wraps around the joint to stop the

excessive movement with each step. Traditionally, the most basic technique is called a DeAngelis technique. This utilises a 100 pound hard line fishing nylon that can be threaded around the joint in various ways. This is the original technique that was used for all cruciate stabilisation procedures, and still is the most cost effective technique for patients up to 15 kg’s

A far superior technique that we have been utilising for some years now is called a Tightrope procedure. This is also a stabilisation technique, similar to DeAngelis in that it stabilises the joint, but uses a titanium-kevlar implant that anchors to the tibia and fibula in a much more secure manner than DeAngelis, also more closely approximating the actual angle of the cruciate ligament itself. This results in faster, better recovery, with less chance of complications and less discomfort to the patient. This is the ideal technique for all patients up to 20kg’s, but is also a reasonable cost effective option for larger dogs if costs may prohibit the superior levelling techniques.

2) Joint levelling techniques:

Levelling techniques aim to change the angle of the tibial plateau (the top of the tibial bone) from it’s normal angle of between 15%-40%, to a more horizontal level, similar to a human knee, such that the normal shearing forces with each step are eliminated, resulting in pain free stability that does not cause ongoing arthritis. These techniques are superior for any patient over 20kg’s where the stabilisation techniques (especially DeAngelis), may not be strong enough to withstand these forces.

The two levelling techniques that SAH offers are:

• TWO (Tibial Wedge Osteotomy) and
• TPLO (Tibial Plateau Levelling Osteotomy)

Both achieve a horizontal tibial plateau, however TWO achieves this via a wedge of bone removed from the tibia which is then re-plated, versus the TPLO which does not remove a wedge of bone, but cuts a circular plane through the Tibia allowing the top of the tibia to rotate around to the desired angle before being re-plated. A TPLO is the absolute Gold Standard of cranial cruciate repair. The advantage of the TWO technique is that it is cheaper and still a very good option, but TPLO is superior.

Which of the above techniques is best for your own dog depends on their age, weight, angle of their tibial plateau, and of course, your budget. Each of our vets can give you a thorough understanding of the problem, and which of the above procedure/s is best for you and your pet if faced with cruciate damage.

• The usual recovery period is 6 to 12 weeks. A series of four anti-arthritic injections are given weekly after surgery, regardless of which procedure is utilised.
• Exercise is slowly built up over this period with your veterinarian helping advise you upon each re-visit.
• There are six scheduled re-visits for which there is no charge. These occur weekly for the first four weeks, then at the 7 and 10 week marks. This ensures we can closely monitor their progress and allows us to communicate with you regarding ongoing care.
• We aim to have dogs off lead and back to normal by 12 weeks post surgery, charging around enjoying life as they did before their injury.

The long term outcome for most patients is excellent!

So Which Procedure is Best for my Dog?

Click here for more information from our advanced surgeon Dr Karin Davids

You may click here to view one of our advanced surgeons teaching associate veterinarians at SAH patella surgery for dogs who have slipping knee caps.

Surgical correction of sub-luxating patellas involves deepening the grove that the kneecap sits in (the femoral trochlea groove), and relocating the bone that the patella attaches to (tibial crest transposition). Click here to read a more detailed article by our head surgeon Dr Karin Davids about the latest thinking in approaches to this surgery.

Trochlea groove deepening: A wedge of bone is sawn out of the trochlea groove, re-modelled and inserted back into the groove. This allows for a deeper groove that the kneecap is less likely to slip out of, but also preserves the cartilage surface of the joint, minimising arthritis risk in the future.

Tibial crest transposition: The tibial crest is the bony prominence at the top of the tibia onto which the patella ligament attaches. The main genetic concern with sub-luxating patellas is that this crest is incorrectly positioned too far to the inside of the joint. Hence we use a bone saw to remove this from the incorrect position and replace it to the more correct front on position.

These two procedures above re align the patella to the normal position, reducing rotational forces that results in not only the luxating patella, but a much higher chance of ruptured cruciates in the future.

The recovery period is 6-12 weeks (less for two knees done at the same time).

Initially we first see you three days after surgery to remove the fentanyl patch (a morphine type transdermal pain killer that makes our patella patients feel very happy after surgery), and give the first of four Cartrophen (Pentosan) injections that help to prevent arthritis. These injections are given weekly for the first four weeks during which time we assess progress, and guide you through building up your pets exercise.

After this four week period, we see you three weekly for two more visits, by which time your pet will just about be fully healed. At Southern Animal Health, all revisits and medications are covered in the initial cost.

The hip joint is a ‘ball and socket’ joint. Hip dysplasia is a disease of the hip joint which causes the joint to develop in an abnormal way, resulting in a shallow socket that the ball does not fit properly into. The shallow, loose joint is then prone to subluxate (partially dislocate). Eventually this condition leads to significant discomfort and lameness and progresses to what is often quite severe osteoarthritis. Risk breeds include Labradors, Golden Retrievers, German Shepherds, Rottweilers, Great Danes, Bernese Mountain Dogs, Saint Bernards, Newfoundlands, Neapolitan Mastiffs, British and French Bulldogs, Basset Hounds, pugs and King Charles Cavalier Spaniels. – Yes, even some small breeds!

The cause of hip dysplasia is multifactorial – mainly genetic, partly dietary, partly growth related and partly unknown. Purchasing a pup bred from parents that have good hip scores (this is determined by X-ray screening) may help to reduce the chance of getting this problem, but is in no way a guarantee. People are often disappointed when purchasing a pup from parents who have great hip scores, only to find out later their pup has severe hip dysplasia.

Hip dysplasia may be suspected (or in very severe cases diagnosed) by palpation for joint laxity (looseness), but requires X-rays of the hip joints under deep sedation or general anaesthesia to definitively determine if hip dysplasia exists. There are many options for treatment of hip dysplasia and these depend on the age of the dog at diagnosis, the severity, and whether or not osteoarthritis is present. ALL dogs diagnosed with hip dysplasia should be desexed due to the hereditary component of this disease.

If you have recently welcomed a puppy into your family, please feel free to contact us to discuss their hips. Early assessment is very important and this is ideally performed between 14-16 weeks of age. Refer to our information on Juvenile Pubic Symphysiodesis (JPS) for more details. For older dogs there are many other medical and surgical options which we can also discuss with you, for advanced cases total hip replacement may be recommended.

We also offer some of the more “pioneering” surgeries such as hip denervation. Hip dysplasia is a debilitating condition that often results in euthanasia when pain killers are no longer working. Hip denervation is an operation whereby we actually remove the nerve supply to the painful hip. Some of the results so far have been remarkable, with dogs having a new lease on life no longer experiencing the pain of severe hip arthritis.

Hence for any surgical procedure feel free to discuss the options with us. We find many clients are sent to specialists from various vet clinics for operations costing thousands of dollars which we could do for a fraction of the price.

Approximately 85-90% of dogs will have significantly improved anatomy, such that they are an excellent chance to not require more involved (and costly) specialist surgical revision at a later time in life such as hip replacement (approximately $8,000 – per side!). Some dogs will still develop hip arthritis but it is far more likely to occur later in life than it would have without JPS, and is also far more likely to be managed well with reduced medications than may otherwise be required.

The images below were taken at SAH by Dr Karin Davids:

1. At 14-16 weeks of age, X-ray the hips under sedation. The normal cost of sedation and X-rays would be $434 however to help at risk patients, we reduce this fee to only $195.

2. If there is evidence of significant hip dysplasia (determined either by joint looseness or X-Ray changes), proceed to general anaesthesia and JPS surgery. The cost of JPS surgery will be $950 in total, inclusive of the X-rays. (Please note, we only recommend this procedure if significant changes are evident. If changes are minor or subtle and we do not feel there is a significant chance of improvement, we do not recommend proceeding with surgery. We will call you at the time of x-rays to discuss).

3. Two months after JPS surgery, follow-up X-rays can be taken at the same time as desexing surgery. The cost of this will be the usual desexing costs, plus follow up X-rays at a reduced fee of just $95.

What if my hips are normal, am I able to be desexed at the same time at 14-16 weeks?

Absolutely! The beauty and flexibility of this process is that the choice is yours. You can choose to desex your dog at the same time, or later if you prefer your dog to grow out a little more. Feel free to discuss early diagnosis and corrective JPS further with any of our veterinarians if you have any more queries.