A fracture is a crack or break in a bone. Nearly every bone in a horse’s body can fracture, but the most common equine fractures involve the bones of the lower limbs. Fractures usually occur either as a result of direct trauma from a fall, kick or knock or during strenuous exercise. Fortunately fractured bones in horses are not too common - but when they do occur many can be repaired with early action, but they do have the potential to be catastrophic.
Types Of Fractures:
- Simple fractures: these have only one fracture line whereas comminuted fractures have multiple fracture lines and pieces of bone have become separated.
- Incomplete fractures: these are cracks that involve only one cortex (side) of the bone and therefore, although painful, remain stable unless they become complete fractures, when the bone fragments separate.
- Stress fractures: these are small incomplete fractures, that most commonly occur in young athletic horses.
- Compound (open) fractures: these involve broken overlying skin, sometimes with the broken bone end clearly visible, whereas in closed fractures, the overlying skin is intact.
- Chip fractures: these involve very small pieces of separated bone whereas larger fragments are called slab fractures.
- Displaced fractures: these are those where the bone fragments have moved apart and there is a gap between them, whereas non-displaced fractures have maintained their normal positions and only a crack is visible.
- Avulsion fractures are where a piece of bone is pulled away by the abnormally strong action of an attached tendon or ligament.
How Are Fractures Diagnosed?
Most limb fractures cause a degree of lameness - varying from mild to non-weight bearing depending on the fracture type and location, so a clinical examination of this lameness is typically the starting point. There is often swelling over the affected area and there is pain on palpation or manipulation of the bone. In stress fractures and some incomplete fractures there may be no external signs except for slight lameness. These cases may require nerve blocks to locate the source of pain. For accurate diagnosis of most fractures, x-rays are essential, and for more subtle fractures, nuclear bone scan (scintigraphic) examinations can help to locate the injury. Ultrasound scans can be useful for fractures of bones in the upper limbs where radiography may not be possible, for example in the pelvis and femur.
How Can You Treat A Fracture?
Fractured bones in horses are, thankfully, fairly rare, as horses are not great patients for fracture repair because, unlike humans who can be instructed to rest in bed or use crutches to bear no weight on the leg, they need to be able to use their legs immediately after surgery.
All fractures require:
- Reduction (setting the bone)
- Stabilising; and
For some simple and incomplete fractures, bandaging, plaster casts or splints can provide enough stability. In more complex fractures, surgery using screws, plates, pins or wires are needed to hold the bone fragments together. Small chip and slab fractures inside joints may be removed successfully using arthroscopic (key-hole) surgery. Choice of treatment technique will depend on site and type of fracture, age and use of the horse and financial considerations.
Unfortunately, many complex fractures, particularly compound (open) fractures and those that involve joints and upper limb bones, are not possible to repair and the horse will require euthanasia.
At Agnew Equine, any surgical candidates will be referred to the most appropriate equine surgeon for your particular case.