Key Points
Bone growth comes from a soft layer of tissue at the ends of the bones called growth plates
This region of the bone is susceptible to developing a fracture in puppies and kittens
This type of fracture usually requires surgery for a good outcome, but in some cases can be managed conservatively
Initial visit- downloadable forms/information for clients:
History sheet - Client initial consultation history
Client education handout - tibial fracture
Discharge instructions after surgery
2-week recheck visit - downloadable forms/information for clients:
History form - 2 week postop (Telemedicine evaluation) - dog
Postop care instructions 2-week fracture repair recheck - dog
8-week recheck visit - downloadable forms/information for clients:
History form 6-week fracture recheck (in hospital) - dog
Postop care instructions 6-week fracture recheck - dog
Downloadable forms for referring veterinarians:
Anatomy
The hind limb has two bones between the knee and the ankle joint: the tibia and fibula bones. The tibia is the larger weight-supporting bone, whereas the fibula bone supports minimal weight. Puppies have much softer bones than adults; therefore more fractures occur in younger dogs. The top and bottom of the tibia bones have a very soft region called the growth plate from which the bone grows. This area is particularly prone to developing a fracture until the growth plate has closed (fused) at 8 to 10 months of age.
Cause of fracture
In small breed dogs, landing on the hind limb from a fall, getting the limb stuck in a hole while running or being stepped on are the most common causes of fracture of the tibia. Overall, growth plate fractures of the tibia bone are much more common in small breed dogs. In large breed dogs, usually substantial trauma is needed, such as being hit by a car.
Surgery
For most fractures of the growth plate of the tibia, one or more pins and sometimes wires are used to repair the fracture. Surgical correction of a fracture of the proximal (top) end of the tibia is essential, as the top of the tibia bone tends to slide downwards. If left unrepaired, the increase in the tibial slope can cause the major stabilizing ligament within the knee called the cranial cruciate ligament to tear with time. In some cases the bones will also heal in a malaligned position.
Surgical fracture repair is performed with placement of at least at least 2 or more pins. Frequently a tension band cerclage wire is also added for additional support, especially if the surgery is performed as an open procedure. Another surgical option is minimally invasive surgery and this can be completed if the fracture is reducible, is freshly fractured (within about 4 to 6 days after injury), or if the fracture is minimally displaced.
Conservative management is usually not recommended for these cases unless the fracture is minimally displaced. In such cases, the pet must be kept in a cage or crate to minimize the displacement of the fracture. Weekly x-rays should be made (until the fracture has healed) to ensure that the fracture is not progressively displacing. If the fracture is chronic and significantly displaced, the fracture is allowed to heal completely (2-3 months) and then a corrective osteotomy is performed to adjust the tibial slope to normal and correct any valgus/varus deformity.
Aftercare
After surgery, you can continue to give your pet a prescribed pain reliever to minimize discomfort. A cast may be placed on the limb for selected fractures and in some cases only a bandage is applied. It’s also extremely important to limit your companion’s activity and exercise level during the post-operative period. Detailed instructions will be given to you after the surgery. The surgeon will monitor the healing process with at least two follow-up exams. The first is scheduled at two weeks after the surgery. During the second exam, at six weeks after the surgery (depending on the age of the pet), radiographs will be made to evaluate the healing bone.
Prognosis
Surgical repair of a fractured tibia offers multiple benefits including a faster recovery, earlier use of the limb after surgery, better chance to return to athletic activity and better range of motion of the joints above and below the fracture. Uncommon complications include infection, shifting of the fractures, breakage of the metal pins or wires and mal alignment of the limb after healing has taken place. Uncommonly, the limb will become twisted as the dog grows due to partial closure of one side of the growth plate.
