Veterinary care has come a long way since the days of old. Many injuries and illnesses that were previously difficult to treat are now routine. Orthopaedic surgery is a great example of this. However, orthopaedics is often still considered a specialist discipline in veterinary medicine. And many owners are in the dark about exactly what it involves. Let’s take a dive into veterinary orthopaedics so things are a little clearer. 

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What is Orthopaedics?

The word ‘orthopaedics’ was created by a French surgeon, but takes its meaning from the Greek ‘ortho-’, meaning straight or correct, and ‘-paidion’, meaning child. This was because the practice of orthopaedics was originally focussed on the correction of skeletal deformities in young children, such as scoliosis or knock-knees. However, what we may recognise as orthopaedics has been practised since at least the Middle Ages (possibly as far back as ancient Egypt – mummified people have been found with bamboo splints attached), in particular during wartime when soldiers would attempt to repair broken bones with splinting.

Modern orthopaedics is a wide discipline covering a variety of conditions involving the musculoskeletal system. This means any problems relating to the bones, muscles and joints of a person (or animal). In humans, common examples of orthopaedic procedures include repairing broken bones, hip replacement operations, and arthroscopy (using cameras to look inside joints).  

Where human medicine goes, veterinary medicine often follows (and sometimes even leads!). For hundreds of years, veterinary medicine was primarily focussed on working animals; in particular horses, where damage to their long legs was common. It wasn’t until the Victorian era that keeping animals as pets really took off. And thus the desire to treat animals after injury was greater. With the inventions of radiography/x-rays and fluoroscopy, as well as safer anaesthetics, vets were able to start repairing broken bones in pets. From here, as new science, aseptic surgery, antibiotics and metal implants became common, veterinary orthopaedics became what it is today, though the discipline advances every year.

What Equipment Do Orthopaedic Vets Use?

Orthopaedic surgery is not as simple at sticking things back together. Most surgeries require specialist equipment and techniques. This can make understanding exactly what your animal is going through tricky. We will now go over common pieces of equipment used in orthopaedic surgeries. Bear in mind that every operation, especially on traumatic injuries, will vary considerably depending on the patient, vet and other factors.

There are a number of important principles that orthopaedic surgeons must consider for every operation. These principles will affect the surgery and equipment used. These principles include ensuring the animal returns to normal function quickly, minimising further damage to tissue, understanding how weight-bearing forces are applied on bones and joints, how damage will heal and much more. Most of the time this will require imaging first, generally radiography or a CT scan. 

Remember that not all vet practices will have an orthopaedic surgeon on the team. So you may need to visit a different vet or be referred to an orthopaedic specialist if you need surgery. This is especially true for more advanced or complicated surgeries.

Intramedullary pins 

These are long metal rods, placed longitudinally in the centre of a bone (the medulla), commonly in bones like the tibia, ulna and femur. IM pins are used to align pieces of broken bone. Their main advantages are that they will prevent the fractured bone from bending or moving sideways; and can be placed without lots of surgical exposure. However, they provide no resistance to twisting or compression across the fracture. Thus, they are rarely used on their own, with plates or cerclage wire needed to resist these forces. IM pins can also sometimes slide out of the bone and protrude from the skin, causing pain and mobility issues.

Cerclage wire 

This is flexible wire that can be bent into multiple shapes, providing a wide range of uses. Often it is looped around bone to prevent movement sideways – it thus works well alongside intramedullary pins. Cerclage wire can also be used to push or pull bone in certain directions when combined with K-pins. Their main disadvantages are that they require more exposure of the bone to apply, and they can slip which delays healing.

K-pins or K-wires

These small thin pins are pushed into bones. They are commonly used when there are fractures across joints in young animals where ensuring the fracture is fitted together perfectly is crucial to avoid ongoing problems with the joint. They can also be used to reattach small pieces of bone that have been pulled off by tendons or ligaments (avulsion damage). They’re commonly combined with cerclage wire to create a tension band. K-pins can be removed after damage has been repaired, whereas many other orthopaedic implants cannot be removed. 

Orthopaedic screws 

Screws look similar to the sorts of screws you might use in furniture, but are much more sophisticated. Aside from being made of stainless steel or titanium, and being sterilised, there’s a lot more to orthopaedic screws than it first appears. Screws can be used to simply hold two pieces of bone together and spread the forces out (positional/neutral screws); or can be used to force pieces of bone closer together (lag/compression screws). Some are designed to fit precisely into orthopaedic plates, but many can be used alone too. Some screws require a screw tap to drill a hole into bone first; while others can drill their own hole as they are implanted. Screws will come in a variety of sizes and shapes depending on the surgery. 

Plates 

Metal orthopaedic plates are designed to fix broken bones together with screws, resist the forces that the weight-bearing leg will apply to the fracture, and ensure the fracture does not move and slow down healing. A properly applied plate will return the broken bone to its normal position to provide quick healing and return to normal function. There are many kinds of plates, and within each kind many sizes designed to fit different bones – usually an orthopaedic surgeon will have to gently bend plates to fine-tune the shape mid-surgery. 

Generally, plates are applied across a fracture, and screws applied through the plate on each piece of bone. Some plates are designed to pull the bones together, while others resist the forces applied to the bone as other implants (like intramedullary pins) hold the bone in place. Because plates cover a large area of bone, they require lengthy and more invasive surgeries. 

External skeletal fixators 

These are complex pieces of equipment that look a bit like a meccano set! They are designed to stabilise fractures but they remain on the outside of the body. Their main advantage is they do not need deep surgical exposure of broken bones. They work via pins that are inserted from the outside into the bone, held in place by rigid frames visible on the outside. ESFs are very good for open fractures or infected wounds that cannot be cleaned for a safe surgery. However, they do not accurately move pieces of bone back into their normal position, meaning they are unsuitable for critical areas like joint fractures. They also open the bone up to infection, since there is a direct hole from the outside to the bone. 

Prostheses 

Prostheses are metal or plastic pieces designed to replace a body part after an amputation, to provide mostly normal mobility. These advanced pieces of equipment are often made bespoke for individual animals. Sometimes they are 3D printed or hand-made, but people have even made their own out of Lego blocks and wheels. 

External prosthesis clip onto an animal via straps, and can be removed easily. There are also transcutaneous prosthesis that are surgically fixed directly to the bones, permanently replacing the missing limb. These have been made famous by certain veterinary TV shows, but do come with significant downsides and controversies. However, if successful, they can potentially give an animal a more normal quality of life. After an amputation, remember that many animals can get along perfectly well on three legs, provided their remaining limbs are healthy, and prostheses are not commonly recommended.  

External coaptation 

This refers to any non-surgical method of stabilising a fractured bone. Splints, casts, heavy bandages and slings are all forms of external coaptation. Their main advantage is that they can be placed without surgery under sedation or general anaesthetic. They are best used for simple fractures with little movement, especially those in young animals. External coaptation cannot be used in complicated fractures, and can lead to swelling of the limb, poor alignment of the bones as they heal, slipping, pressure sores, and muscle wastage. 

So How Would an Orthopaedic Vet Repair a Broken Bone?

Let’s start with a simple scenario – your beloved dog accidentally slipped his lead and got clipped by a car – you think his leg is broken! Thankfully, the driver was kind (and law-abiding) and stopped to drive you both to the local vet. How would an orthopaedic vet proceed in this case?

First of all, any vet, orthopaedic or otherwise, should perform a basic clinical exam

A broken leg is painful, but may not be the most life-threatening injury, provided there is no serious bleeding. There could be brain trauma, internal bleeding, damage to the lungs or other issues that are more serious. A vet will need to check your dog’s breathing and heart rate, pulse, temperature, mental state and more. Further diagnostics involve either a quick x-ray or ultrasound of the chest and abdomen to check for bleeding, and a blood test to check for blood loss. Pain relief and sedation should be administered as first aid. Should there be any life-threatening damage, that will have to be addressed first – a broken leg can be stabilised with a bandage in the meantime.

Luckily, apart from his damaged left back leg, your dog appears to only have scrapes and bruising, and no serious internal damage. 

At this point, once he is considered stable, investigation for the less serious issues can begin, namely the leg

Radiographs will be performed to reveal the damage, showing a broken tibia (shin bone). It’s a single fracture at an angle across the middle of the bone, with no bone protruding from the skin (a simple oblique closed fracture of the diaphysis of the tibia to be precise). The fibula (calf bone) has also been fractured in a similar way. The vet will want to take at least two x-rays from different angles to fully assess the damage. They may want a CT scan too if this is available.

With a diagnosis of a broken tibia, the vet recommends orthopaedic repair to get your dog back to normal as soon as possible. Depending on the type of fracture the vet may have to order in specialist equipment, so surgery may be delayed for a few days. Your dog will need strict cage rest and pain relief in the meantime to avoid further damage.  

The day of surgery comes 

First, the vet explains the procedure, listing some of the equipment they are going to use (some of which you recognise from this article!). Then, your dog will be given a pre-medication to provide more pain relief and keep him calm, before the vet induces anaesthesia and the nurses get him settled under general anaesthetic. His broken leg will then be clipped of hair and surgically cleaned. Local anaesthetic may be applied too. 

In this example, the vet will use a plate and screws to fix the tibia fracture

This will require a lot of exposure of the bone, meaning the surgeon will dissect the skin and muscle away from the leg first. The correct sized plate is chosen and measured against the bone – it needs a little bending to fit perfectly round his tibia. It is placed directly over the fracture and used as a guide to tap holes for screws. The screws are then placed over the plate, with one lag screw connecting the two pieces of bone, holding them firmly attached. The broken fibula is a small non-weight bearing bone, so can be allowed to heal by itself with no orthopaedics needed. The surgeon then closes the muscle and skin with sutures. Two final x-rays are taken to ensure the plate and screws are positioned correctly – they are, so your dog is allowed to wake up to be discharged later that day. 

The orthopaedic vet will want to check your dog a few days post-surgery 

This is to ensure the external wounds are healing. During this time, your dog will need to continue pain relief and have strict rest. Regular check-ups will be needed for the next few weeks, and depending on how he is, he may be allowed to start using his leg again gently. After a month or so, the orthopaedic vet will want to x-ray his leg one more time to check the orthopaedic implants are still in place and the bone has healed. The fracture has almost completely healed so the surgery was a success! The implants will stay in your dog for life, assuming there are no future complications. After a few more weeks of rest, he will be back to normal. Many dogs benefit from post-surgery physio- or hydro-therapy to help build the muscle in the damaged leg back up. 

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