Type C1 fractures are simple articular fractures of the femoral head. The fragment generally remains attached to the ligament of the head of the femur inside the acetabulum and the femur luxates cranially and dorsally.
High-velocity injuries of the proximal femur generally result in intertrochanteric or subtrochanteric comminuted fractures. Low-velocity injuries result in lower energy fractures and often result in two-piece fractures such as capital physeal fractures, femoral neck fractures or transverse fractures of the subtrochanteric region.
The small bone stock available for fixation in the proximal femoral fractures makes treatment of this type of fractures challenging.
31-B fractures are simple fractures of the femoral neck. These fractures may or may not be displaced. Fixation should be performed as soon as possible to avoid abrasion damage and resorption of the femoral neck, making reduction difficult.
Cervical fractures can be intracapsular or extracapsular.
In very young animals, fractures of the greater trochanter may occur concurrently to a capital physeal fractures.
31-C type fractures are uncommon in small patients.
31-C1 and C2 type fractures occur in young animals and most of them occur in combination with coxofemoral luxation. The avulsed fragment remains attached to the round ligament of the femoral head. Prompt surgical intervention is mandatory to minimize damage to the hip joint.
Clinical signs observed in 31-C fractures are:
Crepitus during manipulation of the hip joint
Non weight bearing of the affected limb
Proximal displacement of the greater trochanter due to hip luxation
Good quality mediolateral and craniocaudal radiographs are essential for fracture evaluation. The fragments remaining into the acetabulum may be difficult to identify on radiographs.
If more information is needed, computed tomography should be used.