Mary Allen
Basically, the bones of birds appear pneumatized (air-filled), with the degree of pneumatization varying by species, and serving to improve flight ability by reducing body weight. In cortical bones, there is a higher proportion of inorganic salts in the composition. This leads to greater hardness, but also greater brittleness, which is why birds can be prone to fractures overall.
Symptoms
Broken bones in birds can manifest themselves in symptoms such as instability, reluctance to fly, signs of paralysis, stress, or leaning on one leg. Wings that hang to the side or feathers smeared with blood can also occur with open fractures.
Causes
Fractures can occur due to predisposing causes such as B. Osteomyelitis (inflammation) in local infections of the bird, a poor diet in terms of calcium or calcium-phosphorus ratio (common in young raptors fed beef or offal), or osteoporosis. Bone fractures are also often age-, species-, sex- and hormonal-related: During the laying cycle, females are more susceptible to fractures because the calcium in the bones is mobilized for the formation of the eggs.
Another cause is the shape of the bone itself, e.g. B. the humerus, which is “S”-shaped and allows fractures with certain movements, as well as in bone tumors and the permanent compression of the bones by rings and loops. However, in wild birds, the most common cause is an external dream. In most cases, this is caused by gunshots, collisions with electric cables or wire fences, the chicks falling out of the nest, and being run over (especially in the case of nocturnal raptors).
Treatment Options
The choice of treatment depends on the type of bone and fracture being treated, the size of the bird, the injuries involved, the availability of materials, and financial resources.
One method is external immobilization (bandaging), although the functional outcome for the animal may not be optimal. Some of the most useful bandages include the turtle bandage for fractures beyond the elbow and dislocated elbows or wrists, and the Robert Jones bandage, which is used for fractures in the lower legs, among others. However, there are cases when surgical intervention is necessary for faster recovery and full function of the affected limb.
The use of plates is controversial because the bones of birds are fragile and their cortex is very thin. In addition, they can hardly be adapted to the size and anatomy of certain birds, so metal needles are usually chosen; on the other hand, in birds, the bone callus is inside the bone, so this last method hinders the formation of the bone. Furthermore, in young birds, it can affect the veins that surround the bones, disrupting their development.
On the other hand, the use of unilateral external fixators may also be indicated but must be combined with intramedullary nailing. External fixation does not interfere with bone callus formation, does not damage joints, and does not alter blood supply, so it has great potential to repair fracture injuries in raptors that are difficult to stabilize. These fixators allow the wings to move, making it easier for the bird to start small flights and muscle movements much earlier.