Tarsal Arthrodesis is a surgical elimination of joint motion and, ultimately, bony fusion of joint surfaces. Tarsal arthrodesis is considered a salvage procedure for patients in which other surgical or medical treatment will not restore normal, pain-free joint function. It can relieve pain and restore reasonable limb function.

Surgical Anatomy of Tarsal (Hock) Joint:

  • The hock is compound joint comprising the distal tibia and fibula, the seven tarsal bones, and the proximal metatarsal bones.
  • The proximal row of tarsal bones comprises the talus and the calcaneus, on which the Achilles apparatus inserts.
  • On the medial aspect of the distal tarsus, there are two rows of bones with the central tarsal bone being positioned between the talus and tarsal bones.
  • On the lateral aspect there is only one bone, the fourth tarsal bone.
  • The proximal intertarsal joint comprises the talocalcaneocentral joint medially and the calcaneoquartal joint laterally.
  • The centrodistal joint is the joint between the central tarsal bone and the tarsal bones 1-3.
  • The tarsometatarsal joint is restricted by the numerous ligaments of the tarsus. The most massive of these are the plantar ligaments, which arise from the sustentaculum tali, plantar body, and distal lateral calcaneus and pass distally to insert on the fourth tarsal bone, the othere distal tarsal bones, and the metararsal bones.

Indications for tarsal arthrodesis surgery:

For surgical fusion of the tarsal joints include end-stage degenerative joint disease, chronic or irreparable articular fractures, intra-articular malunions, or nonunions, and servere  joint instability due to loss of ligaments and or bone that cannot be reconstructed successfully.

Surgical Procedure Options for Tarsal Arthrodesis:

  • The tarsal joints can be fused by a pantarsal (complete) arthrodesis or a partial tarsal arthrodesis.
  • When the entire joint is destroyed or diseased, a pantarsal arthrodesis is clearly indicated.

Drs. Brown and Sherburne perform both complete (pantarsal) and partial tarsal arthrodesis fusion surgeries at the Animal Clinic of Billings and Animal Surgery Clinic. Below you’ll find detailed information about both tarsal arthrodesis procedures.

Partial Tarsal Arthrodesis fusion

What is a Partial Tarsal Arthrodesis Fusion?

The tarsal joint is a hind limb joint that connects the tarsal bones to the major leg bones. It exists in the back feet of a dog and restricts certain movements to control range of motion. Excessive degeneration or severe injury can destroy this joint beyond repair. A partial tarsal arthrodesis is a surgery used on a last resort basis to salvage some joint function while fusing leg and foot bones together.

Other treatments that do not affect joint function may be attempted prior to a partial tarsal arthrodesis, or they may be deemed inappropriate at the time of examination. In an arthrodesis, metal implants are surgically placed to decrease movement and relieve pain in the affected limb.

Partial Tarsal Arthrodesis Fusion Surgery on Dogs

To identify where the weakness is in the joint, stress radiographs will be taken. Once the severity of the damage has been assessed, surgery can be planned. Blood work will be run to determine if the dog is healthy enough to undergo general anesthesia. The dog will need to be free of infection before the surgery can be performed.

The dog will need to fast for several hours before the operation. Once it has been sedated, an IV will be placed in the dog. The area of the joint will be shaved and cleaned. An incision can then be made down the leg to begin the procedure. All cartilage will need to be removed from the joint capsule. Bone will be harvested from another area and packed into the empty joint to promote healing. The joint will then be maneuvered into its permanent position. Plates, screws, pins and wires will be used to secure the bones of the joint together. The incision can then be closed using sutures.

Efficacy of Partial Tarsal Arthrodesis in Dogs

A partial tarsal arthrodesis carries an excellent prognosis, offering more movement than a complete tarsal arthrodesis. Because of the increase in joint function, this procedure is preferred if at all possible. Many dogs experience normal or almost normal leg movement after a successful partial tarsal arthrodesis has been performed. Surgical treatment yields much better results than non-invasive treatments of severely damaged tarsal joints. Joints that are completely destroyed may require a surgical procedure called a “panarthrodesis” instead.

Partial Tarsal Arthrodesis Recovery in Dogs

The dog will have to be closely monitored as it wakes up from the general anesthesia to ensure all vital functions resume properly. Pain medication can be administered at this time and may continue for several days post-surgery. A bandage will be placed over the surgical wound to help manage both swelling and bleeding. This dressing will need to be changed every one or two weeks until the site has healed.  The limb will need to be placed in a cast or attached to a splint for stabilization as it heals from the operation. The cast or splint will need to remain for at least six weeks. Exercise should slowly resume once the external support has been removed.

Dog Partial Tarsal Arthrodesis Considerations

There are certain complications that can arise after a partial tarsal arthrodesis. Infection of the surgical site can hinder proper healing of the joint. The metal implants may break, or cause severe sensitivity to the cold, both of which would require further surgery for removal. If the joint does not heal, a second bone graft may be needed.

The cast may cause pressure sores to develop. If the fixation is not rigid enough, the joint can become unstable. Some dogs may also experience death of the tissue on the base of the foot. The use of general anesthesia also comes with rare but serious risks that need to be considered before operating on the animal.

Partial Tarsal Arthrodesis Prevention in Dogs

To prevent the need for a partial tarsal arthrodesis, both severe and minor injuries should be avoided. Severe injuries, often caused by vehicle accidents, can be prevented with the use of a leash whenever the dog is being walked. Minor injuries that can lead to arthritis can be avoided by discouraging jumping off of high surfaces or onto hard surfaces. Vigorous play should not be permitted in order to avoid leg injuries. Daily supplementation with glucosamine and chondroitin can help slow down the progression of degenerative arthritis so that surgical intervention is not needed.

Complete Tarsal Arthrodesis Fusion

What is a Pantarsal (Complete Tarsal) Arthrodesis Fusion?

Arthrodesis is the fusing of low motion joints, performed when injury or deterioration in these joints causes disorder and pain to your dog. Pantarsal arthrodesis is achieved with the surgical application of bone material in the joints and metal plates to the surfaces of the tibiotarsal, proximal and distal intertarsal and tarsometatarsal joints. These joints have limited or no range of motion and fusing them does not prevent your dog from walking or moving about, but relieves pain in the damaged joint. The insertion of surgically implanted metal plates to fuse the joint may be used when trauma to the bones or soft tissue of the joint has occurred, or degenerative disease such as osteoarthritis occurs. The resulting fixation of the joint to resolve the condition can be an alternative to limb amputation. Pantarsal arthrodesis in dogs is performed under general anesthetic by your veterinarian with the use of appropriate surgical plates to fixate the tarsal joints.

Complete Tarsal Arthrodesis Surgery on Dogs

Fixation of surgical plates may be external or internal to the joint, depending on the type of damage or disease, and what method will be most effective. A variety of different size plates are available and the correct size needs to be selected in order for fixation to be successful. Radiographs taken prior to surgery will be used to plan the surgical procedure and to address the approach and plates to be used.

Prior to surgery, you will be required to fast your dog so as not to cause complications with the administration of general anesthetic. Your dog will be sedated, given intravenous anesthetic and then intubated and anesthesia maintained by gas. The area to be incised on the tibia and tarsal joints is shaved and antiseptically cleaned prior to incision. Surgical drapes are used to maintain a sterile surgical site. An incision is made from the tibial area to the metatarsal joint. Subcutaneous tissues are cut away to expose muscles and ligaments that are then moved aside with the use of retractors. Joint capsules are destroyed or repairs made to bone and soft tissue as required. Bone grafts are used to fill joint spaces and achieve bone fusion. Specialized surgical plates are affixed with surgical screws to the tibia, tarsus, and metatarsus as required to fix the joint. Incisions are closed and a splint bandage may be used to support the leg and joint. Your dog will be assisted while they recover from anesthetic and administered supportive care as necessary.

Efficacy of Pantarsal Arthrodesis in Dogs

Pantarsal arthrodesis, achieved with surgical intervention and implantation of plates, is usually effective at fusing the joint and relieving pain in the hindlimb of dogs. When pantarsal arthrodesis is not successful, it may be due to poorly sized or fitted plates or plates loosening or breaking, resulting in fusion not being achieved. This procedure can be a successful alternative to limb amputation.

Complete Tarsal Arthrodesis Fusion Recovery for Dogs after surgery

After pantarsal arthrodesis surgery, your dog’s activity should be restricted for three to four weeks. A splint bandage may be used during this time if deemed necessary to immobilize the hind leg while healing of the surgical site occurs. Sutures will need to be removed in 10 to 14 days if nonabsorbable sutures or staples were used. Your veterinarian may prescribe pain killers and antiinflammatories, which should be administered as directed. If risk of infection is suspected, antibiotics may also be prescribed. Inspect the surgical incision routinely to ensure that wound rupture or infection is not occurring and address with your veterinarian if this should occur. You may need to use an e-collar to prevent your dog from interfering with bandaging or sutured incision site.

Dog complete tarsal Arthrodesis surgery Considerations

Complications from disease present, general anesthetic, and infection are risks inherent in this procedure which can be mitigated with appropriate supportive care.

Proper size selection and necessary plate customization to ensure adequate fit for your dog’s tarsal area are critical to the success of the procedure. Plates that are too small can break, and plates that are too large may not provide adequate structural support to the bone.

Tarsal Arthrodesis Prevention in Dogs

Osteoarthritis, which is a common cause of the requirement for joint arthrodesis, may not be preventable. However, injuries that may contribute to osteoarthritis or trauma that could directly result in the requirement for pantarsal arthrodesis can be mitigated. Ensuring your dog’s environment is safe from hazards and that they are not left unsupervised or loose outside will greatly reduce the likelihood they will be involved in household accidents, motor vehicle accidents or fights with other animals resulting in injury to the tarsal joints. In addition, early intervention when osteoarthritis presents may allow for treatment that can prevent surgical intervention being necessary.