Cruciate Surgery On A Small Dog - Is It Necessary?
Paddywhack was a cross breed, Yorkshire terrier, maybe some westie or other type of small terrier. He was rescued from Ireland and a strong natured dog yet easy to live with and generally low energy.
Running down a hill one day Paddywhack became suddenly and severely lame on one back leg. He was taken directly to a vet, in a new surgery to both him and his guardian. The veterinarian was insistent on surgery and didn’t talk through the options, stating that the dog needed surgery immediately and they were to do a loop type surgery around the leg based on a broken cruciate ligament. Fist to remove the dog’s suffering and secondly to avoid arthritis and pain in the future. The dog was booked in for the next day.
Tearing or breaking of the cranial cruciate ligament is one of the most common knee injuries in dogs. There are two cruciate ligaments within the knee and they cross over each other in the middle of the knee. When the cranial cruciate ligament is damaged, the tibia slides forward, which can be felt with small manipulation of the dog’s leg and is known as a positive drawer sign. The surgery carried out on Paddywhack was the traditional ECLS meaning that the joint is stabilised with a single suture from outside the joint capsule. The suture means that two tiny holes are drilled into the tibia and the femur to allow the loop to pass through. This is the oldest method of repair for this type of injury.
Fig 1  Illustration of the dog’s knee anatomy showing the cranial cruciate ligament in a ruptured state (shown in blue/purple) whilst the knee pushes forward into the other ligaments of the knee joint.
Post-surgery there was no advice given on rehabilitation, and Paddywhack really suffered. For two days he screamed and cried. He was given painkillers and sat with throughout this time but the operation and how he felt afterwards obviously caused a lot of trauma for him. He was prescribed 8 weeks crate rest he was walked out in a buggy after the first week, he was naturally quiet in the house and eventually his leg healed. His face hair also turned white from a deep tan colour.
A year later Paddywhack broke the cruciate ligament on his other back leg. One study tells us that on average 22% of cases ruptured their second leg cruciate 14 months after the first. In the majority of cases the cruciate ligament ruptures as a result of long term degeneration, there is no known cause bit the fibres in the ligament weaken over time. There may be a genetic factor to this type of disease and certain breeds are considered pre-disposed, inclusive of the West Highland terrier which is Paddywhack’s size and shape. 40 to 60% of dogs with a crucial ligament rupture in one knee will present with a rupture in the second knee – usually over time in a period of degeneration. Partial tearing is common and it will usually progress to a full tear over time. 
Other health issues at the time prevented a second surgery and therefore no surgery took place. The dog was walked in a buggy and quiet at home as he was in the initial healing process, but without the surgery and with pain relief via NSAIDS. A few weeks later and the lameness was no longer apparent. By six months later both back legs were functional, no severe lameness was present and the dog was back to full strength. A few years later Paddywhack died of a rare form of liver cancer, that was inoperable and untreatable, he still showed no significant lameness or signs of pain in either leg. Just being marginally wobbly on both.
So then we have to ask ourselves was the first surgery necessary at all? If the signs of pain are the same on both legs, the healing process takes the same amount of time and in the long(er) term both legs offer exactly the same support in the dog’s observed gait – why then did he go through the severe trauma of bone surgery for the first leg?
To prevent arthritis in the future?
Osteoarthritis is one of two types of arthritis that affects the joints by inflammation through wear and tear. The disease is degenerative and is thought to affect twenty percent of senior dogs. The disease is characterised by the loss of articular cartilage and formation of irregular new bone. Articular cartilage covers and protects the ends of bones in most joints of the body. The cushioned surface on the ends of the bones slowly wears away, meaning bone rubs directly on bone, causing pain, swelling, stiffness and reduced mobility.
Causes of OA may be secondary to trauma/ injury e.g. following cranial cruciate ligament rupture Symptoms of OA include reduced activity: reluctance to exercise, stiffness, lameness, inability to jump or reluctance to climb stairs. Pain: reluctance for joints to be touched, behavioural changes such as aggression or signs of discomfort.
Pain relief is crucial e.g. Non-steroidal anti-inflammatory drugs (NSAIDS) (carprofen, meloxicam, deracoxib, ketoprofen etc.). Joint supplements: e.g. chondroitin sulphate, glucosamine sulphate, omega-3-fatty-acid supplementation. Weight control or reduction: reduce weight to take excess pressure off joints. Activity modification: regular controlled and low impact exercise Surgical treatment: Surgery may be indicated and in some cases, it is the best treatment option (including cranial cruciate ligament rupture) 
OA is a progressive disease, meaning it normally gets worse over time. The conservative approach with pain relief and joint supplements can slow down the progression of disease and many dogs can live comfortably for years following diagnosis.
Surgical Repair Prognosis
The American college of veterinary surgeons tells us that the long term prognosis for dogs undergoing a surgical repair is good – stating a significant improvement of 85-90% of cases and that arthritis can develop post-surgery yet surgery is considered to slow its progress. 
Another study specifically exploring the long term prognosis tells us that whilst surgical treatment is advocated to repair the cruciate ligament and stabilise the joint the type of surgery makes a difference. The joints rarely fully return to the state of healthy limbs – specifically within the extension and flexion angles.
Paddywhack’s guardian was given one option – surgery and one option for that surgery. There were so many other choices that could have been discussed and this became even more apparent when the second leg healed without surgery. The surgery he was given has complications. First the pain and trauma associated with a bone surgery, albeit minimal. Secondly the suture could fail and progressive development of arthritis still occur. The failure of the suture could also mean that the repair could need to be redone if the dog guardian and veterinarian opted for that.
As was shown by the dog’s body, surgery may have been a rash decision that could have saved the small dog pain and trauma. They type of surgery used was also old surgery even back then and whether the vet assumed to keep cost low – we could not possibly know. Yet if this was the case, could the vet have also considered and discussed less invasive and traumatic options altogether? Could they have given the dog’s guardian more information thus empowering with more choices?
Pain relief is a definite requirement for this type of injury/disease. Only a veterinarian can diagnose and prescribe canine pain relief and usually with this type of injury the use of pain relief and anti-inflammatory medicines are kinder to the dog, based on the nature of not only pain but joint inflammation too. NSAIDs are the most commonly used pain medication for dogs, and they have great pain relieving, anti-inflammatory and anti-fever properties. They work by blocking the body’s production of certain enzymes that cause tissue swelling and pain at the point of injury. NSAIDs are usually a safe and effective form of pain relief, but they can cause side effects. They are not suitable for all patients, especially animals with dehydration, low blood pressure or underlying kidney or liver problems. NSAIDS that cause problems for the dog in pain can be replaced with straightforward pain relief and steroids for reducing inflammation. Steroids and opioids can be used together for both a painkilling and anti-inflammatory effect. Joint supplements are a common and well-used add in for a dog with joint issues or pain from arthritis and joint issues such as Cruciate ligament rupture. A quality joint supplement is often advised by a veterinarian post-surgery to a dog guardian to aid the joint getting back to full strength.
Whilst the point of surgery is to attempt a repair of the joint, there are a number of ways that rehabilitation can be helped along and even when surgery is carried out – rehabilitation is still required.
So we could have begun with pain relief and rest. Conservative pain treatment has been considered best suited to dogs weighing less that 15kg, Paddwhack was 10 kg. As we did with the second leg. The option of a leg brace to hold the leg in place and prevent the knee slipping forward and to support the stifle may have been a kind choice. The goals of non-surgical management of the injury are to address the dog’s pain and support them until the limb returns to full function. 
Complimentary therapies are available for dogs whether they have had surgery or not. They may include physiotherapy for dogs.
Physiotherapy when taking the conservative approach according to Fitzpatrick referrals  in the first 6 weeks would aim to reduce inflammation, reduce muscular guarding, increase strength and limb loading, maintaining soft tissue length and flexibility. This is usually carried out in the water through hydrotherapy. From 6 to 12 weeks exercise tolerance would be increased and at 12 weeks we could expect at least the start of a return to full function. The rehabilitation period for post-surgery follows a similar process over a similar timescale, with the hope that the dog will recover better in the long term.
For this case study in particular it seems that the dog was put through something that could have been avoided with an all-round educated approach. The dog’s guardian was ill-informed and thus the dog had a traumatic surgery which may not have been necessary.
 https://vcahospitals.com/know-your-pet/cranial-cruciate-ligament-repair-extracapsular-repair-and-tightrope-procedure Sourced 24th August 2020  http://csu-cvmbs.colostate.edu/vth/small-animal/sports-medicine-rehabilitation/Pages/canine-cruciate-ligament-injury.aspx 24th August 2020  https://pubmed.ncbi.nlm.nih.gov/8579557/ sourced 24th august 2020  https://www.fitzpatrickreferrals.co.uk/orthopaedic/cranial-cruciate-ligament-injury/ sourced 24th August 2020  https://www.acvs.org/small-animal/cranial-cruciate-ligament-disease sourced 24th August 2020  Canine Principles Senior Dog Care Course Sourced 24th August 2020  https://www.acvs.org/small-animal/cranial-cruciate-ligament-disease Sourced 24th August 2020 doi:10.1186/s12917-014-0266-8 Cite this article as: Mölsä et al.: Long-term functional outcome after surgical repair of cranial cruciate ligament disease in dogs. BMC Veterinary Research 2014 10:266.  https://www.theveterinarynurse.com/review/article/cruciate-ligament-disease-and-the-role-of-the-balto-knee-brace Sourced 24th August 2020  https://www.fitzpatrickreferrals.co.uk/rehabilitation/rehabilitation-of-cranial-cruciate-ligament-ccl-disease/ Sourced 24th August 2020