Subtalar arthrodesis is a surgical procedure aimed at fusing the subtalar joint, which is located between the talus and the calcaneus in the foot. This joint plays a crucial role in foot motion and stability, particularly in the way the foot moves up and down. In cases where the subtalar joint becomes damaged due to conditions like osteoarthritis, trauma, or congenital deformities, subtalar arthrodesis is performed to relieve pain and restore function.
What is Subtalar Arthrodesis?
Subtalar arthrodesis, often referred to as subtalar fusion, involves surgically fusing the two bones of the subtalar joint. This process is typically recommended for patients who have severe arthritis or other debilitating conditions that affect the joint, causing persistent pain. The goal is to eliminate the movement at the joint, which reduces pain, although it can also limit the joint’s range of motion.
The procedure is generally carried out under general anesthesia, and it involves creating an incision near the subtalar joint to expose the bones. The damaged cartilage is removed, and bone grafts are used to promote healing and fusion. A screw or other fixation device is inserted to hold the bones together while they fuse.
Why is Subtalar Arthrodesis Done?
Subtalar arthrodesis is commonly performed in cases of:
Post-Traumatic Arthritis: This occurs after an injury, like a fracture, that disrupts the normal structure and function of the joint.
Primary Osteoarthritis: A condition where the cartilage in the joint degenerates over time due to aging or repetitive stress.
Tarsal Coalition: A condition in which there is an abnormal connection between two or more bones in the foot, leading to stiffness and pain.
Inflammatory Joint Disease: Conditions like rheumatoid arthritis, which can severely damage the joint.
In all these cases, the goal is to alleviate pain and improve foot function by preventing further movement of the damaged joint.
The Procedure
Subtalar arthrodesis is usually performed using a well-established surgical technique. A horizontal incision is made near the ankle and subtalar joint, exposing the affected area. After removing the damaged cartilage, the bones are aligned properly, and a bone graft is often used to help with healing.
A screw is placed across the joint to keep the bones in place as they fuse. In some cases, a structural bone graft from the iliac crest (the top part of the pelvis) may be needed if there is significant damage to the joint or if additional support is required.
After the procedure, the patient’s foot is placed in a cast, and weight-bearing is restricted for several weeks. The fusion process takes time, typically several months, and during this period, follow-up appointments are crucial to ensure the bones are healing properly.
What to Expect After Surgery
Post-operative care following subtalar arthrodesis is critical for successful healing. Initially, patients will need to avoid putting weight on the foot for several weeks to allow for proper fusion. Typically, a cast or splint is worn for the first 6 weeks. After that, patients are gradually allowed to bear weight on the foot, although full weight-bearing activities may not be possible until several months after surgery.
Patients will have follow-up visits where radiographs are taken to monitor the progress of the fusion. If the fusion is not progressing as expected, additional imaging, like a CT scan, may be necessary. Some patients may experience pain or discomfort during the healing process, and medications or physical therapy may be prescribed to help manage these symptoms.
Risks and Complications
Like any surgical procedure, subtalar arthrodesis carries certain risks, including:
Nonunion: This is when the bones do not fuse together as intended. This can result in continued pain and may require additional surgery.
Infection: As with any surgical procedure, there is a risk of infection at the incision site.
Chronic Pain: Some patients may experience persistent pain, even after the fusion is complete.
Stiffness: Since the joint is fused, patients may experience limited motion in the affected foot. This can affect walking and other activities, but many people adapt well to the change in mobility.
Expected Outcomes
The success rate of subtalar arthrodesis is generally high, with most patients experiencing significant pain relief and improved function. According to a study on the outcomes of subtalar arthrodesis, 95% of patients achieve a radiographic union, which means the bones heal and fuse together as expected.
Most patients report good to fair outcomes, with 93% experiencing either no pain or only minimal discomfort after heavy use.
However, some complications can arise, such as nonunion (failure of the bones to fuse), chronic pain, or post-traumatic arthritis in the ankle joint. Despite these risks, the majority of patients benefit greatly from the procedure, regaining the ability to perform daily activities without the debilitating pain they experienced before surgery.
Conclusion
Subtalar arthrodesis is an effective surgical treatment for various conditions that cause pain and dysfunction in the subtalar joint. The procedure involves fusing the bones in the joint to eliminate painful motion, thereby providing long-term relief for patients suffering from severe arthritis, trauma, or congenital issues.
While the recovery process can be lengthy, with proper care and follow-up, most patients experience significant improvements in their quality of life. If you are considering this surgery, it’s essential to discuss your options with your orthopedic surgeon to determine if subtalar arthrodesis is the right choice for your specific condition.
