An avulsion fracture occurs when a tendon or ligament attached to the bone pulls away from the bone. Tuberosity is the term used to describe the prominence of a bone that attaches the ligament to the bone. Tibial tuberosity fractures affect the patellar ligament near the kneecap. These types of fractures are quite rare in cats, and are most commonly diagnosed in young animals between four and eight months old. There are no sex or breed predisposition for tibial tuberosity avulsion fractures.

Signs of a tibial tuberosity avulsion fracture will manifest quickly and cause extreme pain for your cat. These types of fractures must be addressed as quickly as possible in order to prevent further complications and secure the best prognosis for your cat. Seek immediate veterinary attention as soon as you notice any of the following symptoms:

The primary cause of tibial tuberosity avulsion fractures in cats is traumatic injury. Most cats who experience avulsion fractures do so after jumping or falling from a significant height. These types of fractures occur more often in young animals whose growth plates are weaker when compared to adult cats.

Your vet will be able to make a tentative diagnosis based on a thorough physical examination and presentation of symptoms. Be sure to inform your vet of the extent and duration of your cat’s symptoms, as well as any previous history of fractures or recent traumatic injuries that you know of.

Your vet will make a definitive diagnosis by taking an x-ray of the knee and leg. Your vet may choose to administer an oral pain medication to soothe your cat during the x-ray. Additional testing is generally not required, although your vet may conduct standard diagnostic testing in the event that surgical treatment is necessary. This may be done to determine if your cat is healthy enough to undergo anesthetization.

Treatment may vary depending on the severity of the fracture. Tibial tuberosity avulsion fractures may be treated conservatively or with surgery. However, surgery is the treatment of choice in most cases of fracture. Your vet will be able to advise you on a treatment plan based on your cat’s specific needs.

Your cat will be anesthetized prior to surgery. Surgical correction of the fracture will involve placing the displaced ligament back into its correct position. A combination of screws, pins, and/or wires may be required to hold the ligament in place. The tension band method is generally preferred for treating tibial tuberosity avulsion fractures. This involves the use of special pins and cerclage wire. However, this method may cause complications and/or deformity, so the use of screws and/or pins may be advised instead.

The operation site will then be sutured shut, and a bandage will be placed over it. The sutures may or may not be dissolvable. Your vet will be able to advise you on whether suture removal is required. Analgesics for pain may be prescribed following surgery.

Recovery and prognosis may vary depending on the severity of the fracture and whether or not there are any complications following surgery. Always follow your vet’s post-treatment and/or post-operative instructions carefully.

Your vet will wrap a special bandage around the operation site, which is usually left in place for up to twelve days. On the return home, ensure your cat has a warm, safe place to rest. If your cat has had surgery, never allow them to irritate the surgery site. An Elizabethan collar may help with this.

Your vet will typically recommend that movement be restricted for up to five weeks following surgery.  Ideally, you should restrict your cat’s outdoor activity to avoid further injury. It may be a good idea to confine them to a small space in order to restrict movement and promote healing. You may want to limit your cat’s outdoor activity in the future, or monitor them while outside, in order to prevent future falls.

Your vet will usually schedule follow-up appointments within a month following surgery to monitor healing. During this appointment, your vet will take an x-ray to ensure that no complications have occurred. Your vet may choose to schedule another follow-up appointment within two to four months following surgery to monitor healing. Additional follow-up appointments may be scheduled as needed, particularly if the sutures are not dissolvable.

If you have any questions, or if you notice any swelling, signs of infection or other complications following surgery, contact your vet immediately.