Subtalar arthrodesis is a surgical procedure designed to fuse the subtalar joint, which is located between the talus and calcaneus bones in the foot. This joint is essential for foot movement and stability, particularly in terms of the foot’s ability to move up and down. When the subtalar joint is damaged due to conditions such as osteoarthritis, trauma, or congenital deformities, subtalar arthrodesis can provide pain relief and restore foot function.
How Common It Is and Who Gets It? (Epidemiology)
Subtalar joint problems are often associated with traumatic injuries, such as fractures, and degenerative conditions like osteoarthritis. Individuals who have suffered fractures in the hindfoot or those with degenerative joint disease are at higher risk for needing this surgery. The procedure is generally recommended for patients with chronic pain and dysfunction in the subtalar joint.
Why It Happens – Causes (Etiology and Pathophysiology)
Subtalar arthrodesis is performed in cases of joint degeneration or instability caused by various conditions:
- Post-traumatic arthritis following a foot injury or fracture
- Primary osteoarthritis, which results from wear and tear on the joint over time
- Tarsal coalition, where bones in the foot are abnormally fused, causing stiffness and pain
- Inflammatory joint diseases, such as rheumatoid arthritis, which cause joint damage
How the Body Part Normally Works? (Relevant Anatomy)
The subtalar joint is located below the ankle joint and allows for critical foot movements such as inversion and eversion. These movements are necessary for walking, running, and adapting to uneven surfaces. The talus and calcaneus bones articulate to provide these functions, with cartilage cushioning the joint surfaces for smooth motion.
What You Might Feel – Symptoms (Clinical Presentation)
Patients suffering from conditions affecting the subtalar joint often experience chronic pain, particularly with weight-bearing activities. They may have difficulty walking, standing, or participating in sports due to limited foot mobility. The foot may also become stiff or swollen, especially after physical activity.
How Doctors Find the Problem? (Diagnosis and Imaging)
To diagnose subtalar joint issues, doctors will conduct a physical exam to assess pain, swelling, and limited motion. Imaging studies, such as radiographs (X-rays), CT scans, and MRI scans, are used to confirm the diagnosis, determine the severity of the condition, and evaluate bone and joint alignment.
Classification
Subtalar joint conditions are typically classified based on their severity, ranging from mild osteoarthritis to advanced joint degeneration or post-traumatic arthritis. In some cases, tarsal coalition may also be classified based on the number of bones involved and the degree of fusion.
Other Problems That Can Feel Similar (Differential Diagnosis)
Conditions that may present with similar symptoms include Achilles tendinopathy, plantar fasciitis, and midfoot arthritis. It’s important to differentiate subtalar joint issues from other foot and ankle problems to ensure accurate diagnosis and treatment.
Treatment Options
Non-Surgical Care:
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- Activity modification
- NSAIDs for pain relief
- Ankle-foot orthoses (AFOs) or custom orthotic devices
- Corticosteroid injections for inflammation
- Physical therapy to improve flexibility and strength
Surgical Care:
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- Subtalar arthrodesis (fusion) is performed when conservative treatments fail to provide relief. The procedure involves fusing the bones of the subtalar joint to eliminate painful motion.
Recovery and What to Expect After Treatment
Recovery from subtalar arthrodesis typically takes several months. Patients will need to avoid putting weight on the foot for the first 6–8 weeks. Gradual weight-bearing is allowed after this period, but full recovery, including the return to high-impact activities, may take 6 months or longer. Regular follow-up appointments are essential to monitor healing and ensure the fusion process is progressing.
Possible Risks or Side Effects (Complications)
- Nonunion: When the bones do not fuse as expected, leading to ongoing pain and the potential need for further surgery.
- Infection: As with any surgical procedure, there is a risk of infection at the incision site.
- Chronic pain: Some patients may continue to experience discomfort, even after the fusion is complete.
- Stiffness: The fusion results in a loss of motion in the subtalar joint, which can affect walking and other activities.
Long-Term Outlook (Prognosis)
Most patients experience significant pain relief and improved function after subtalar arthrodesis, with a high success rate. However, the fusion of the subtalar joint limits certain movements in the foot. Despite this, the majority of patients can resume normal daily activities with little discomfort, although high-impact sports may not be possible for some.
Out-of-Pocket Cost
Medicare
CPT Code 28725 – Subtalar Arthrodesis (Fusion of the Subtalar Joint): $182.74
Medicare Part B typically covers 80% of the approved cost for this procedure once your annual deductible has been met, leaving you responsible for the remaining 20%. Supplemental Insurance plans such as Medigap, AARP, or Blue Cross Blue Shield usually cover that remaining 20%, minimizing or eliminating out-of-pocket expenses for Medicare-approved surgeries. These plans work alongside Medicare to fill the coverage gap and reduce financial responsibility.
If you have Secondary Insurance, such as TRICARE, an Employer-Based Plan, or Veterans Health Administration coverage, it acts as a secondary payer. These plans generally cover any remaining balance, including coinsurance or small deductibles, which typically range between $100 and $300, depending on your plan and provider network.
Workers’ Compensation
If your subtalar arthrodesis is needed due to a work-related injury, Workers’ Compensation will cover all associated medical expenses, including surgery, postoperative care, and rehabilitation. You will not have any out-of-pocket costs, as the employer’s insurance carrier directly covers all approved costs.
No-Fault Insurance
If your subtalar joint fusion is needed due to an automobile accident, No-Fault Insurance will typically cover the full cost of your treatment, including surgery and follow-up care. The only potential out-of-pocket cost may be a small deductible or co-payment, depending on your policy.
Example
David Anderson had severe arthritis in his subtalar joint and required subtalar arthrodesis (CPT 28725). His estimated Medicare out-of-pocket cost was $182.74. Since David had supplemental insurance through AARP Medigap, his remaining balance was fully covered, leaving him with no out-of-pocket expenses for the surgery.
Frequently Asked Questions (FAQ)
Q. What is Subtalar Arthrodesis?
A. Subtalar arthrodesis is a surgical procedure that involves fusing the subtalar joint, which lies between the talus and calcaneus bones in the foot. This is done to alleviate pain and improve stability, particularly in cases of severe arthritis or foot deformities.
Q. When is Subtalar Arthrodesis recommended?
A. It is recommended for patients with conditions like post-traumatic arthritis, primary osteoarthritis, tarsal coalition, or inflammatory joint disease that cause chronic pain and limited movement in the subtalar joint.
Q. How is Subtalar Arthrodesis performed?
A. The procedure involves creating an incision near the subtalar joint, removing damaged cartilage, and fusing the talus and calcaneus bones using screws or other fixation devices. Bone grafts may also be used to promote healing.
Q. What is the recovery time after Subtalar Arthrodesis?
A. Recovery can take several months. Patients typically wear a cast or boot for 6 to 8 weeks, followed by gradual weight-bearing. Full recovery, including the return to high-impact activities, may take 6 months or longer.
Q. What are the risks associated with Subtalar Arthrodesis?
A. Risks include infection, nonunion (failure of the bones to fuse), stiffness, nerve injury, and adjacent joint degeneration. However, these risks are relatively rare and can often be managed with proper care.
Q. What is the success rate of Subtalar Arthrodesis?
A. The procedure has a high success rate, with 95% of patients achieving a radiographic union and significant pain relief. Most patients experience good to fair outcomes, with improved foot function and stability.
Q. Can Subtalar Arthrodesis be performed on both feet at the same time?
A. While it is possible to perform the procedure on both feet, it is usually done one foot at a time to ensure proper healing and minimize complications.
Q. How does Subtalar Arthrodesis affect foot mobility?
A. Since the procedure fuses the subtalar joint, some range of motion in the foot will be lost, particularly in ankle inversion and eversion. However, the procedure is generally successful in restoring stability and reducing pain, allowing patients to return to normal activities.
Q. Will I need physical therapy after Subtalar Arthrodesis surgery?
A. Yes, physical therapy is recommended to help restore strength, flexibility, and range of motion in the foot and ankle, as well as to improve gait and prevent stiffness after surgery.
Q. Can Subtalar Arthrodesis treat flatfoot deformity?
A. Yes, Subtalar Arthrodesis can be effective for treating flatfoot deformities caused by excessive pronation or instability in the subtalar joint, especially when other treatments have not provided relief.
Q. Will I experience pain after Subtalar Arthrodesis surgery?
A. Most patients experience significant pain relief after the joint has healed. Some discomfort or swelling is normal during the recovery process, but this usually improves over time.
Q. Can I return to running after Subtalar Arthrodesis surgery?
A. Running and high-impact activities are typically not recommended until the joint has fully healed, which can take 6 months or longer. Patients are encouraged to resume light activities once the foot has stabilized.
Q. How is Subtalar Arthrodesis different from other foot fusion procedures?
A. Subtalar Arthrodesis specifically targets the subtalar joint, while other foot fusion procedures may address different joints, such as the MTP joint or midfoot. It is particularly effective for conditions affecting the subtalar joint’s stability and function.
Q. Will my foot look different after Subtalar Arthrodesis surgery?
A. The appearance of the foot may change slightly due to the fusion, but the primary goal of the procedure is to restore function and stability. Cosmetic changes are usually minimal.
Q. Is Subtalar Arthrodesis a permanent solution?
A. Yes, Subtalar Arthrodesis is a permanent solution for relieving pain and improving stability in the foot. However, it is important to follow rehabilitation protocols to prevent complications and ensure long-term success.
Summary and Takeaway
Subtalar arthrodesis is a highly effective surgical treatment for alleviating chronic pain and dysfunction in the subtalar joint, particularly when caused by conditions such as arthritis or trauma. The procedure involves fusing the talus and calcaneus bones, eliminating painful movement, and restoring foot stability. While recovery takes time and requires following strict rehabilitation protocols, the majority of patients experience significant improvements in function and pain relief. This surgery is generally a permanent solution, though patients may experience a loss of range of motion. If you’re experiencing ongoing foot pain that does not improve with conservative treatments, subtalar arthrodesis could offer the relief you need to return to normal daily activities.
Clinical Insight & Recent Findings
A recent study evaluated the outcomes of posterior arthroscopic subtalar arthrodesis performed without bone grafting and found that this minimally invasive approach effectively preserves hindfoot height and function. Among 39 patients, the average loss in hindfoot height was less than 1 mm, with a 95% fusion success rate and significant pain reduction. The procedure also demonstrated excellent accuracy and consistency when assessed using CT scans. Notably, the study reported no negative impact on bone fusion or functional outcomes, suggesting that posterior arthroscopic fusion offers reliable results while maintaining natural alignment—an important advantage over traditional open techniques. (“Study on preserving hindfoot function after subtalar fusion – see PubMed.“)
Who Performs This Treatment? (Specialists and Team Involved)
Orthopedic surgeons specializing in foot and ankle surgery typically perform subtalar arthrodesis. In some cases, a multidisciplinary team, including physical therapists and pain management specialists, may be involved in the preoperative and postoperative care.
When to See a Specialist?
If you have persistent pain in the foot or ankle that does not improve with conservative treatments, it’s important to consult a specialist. They can evaluate the severity of the condition and determine if surgical intervention is necessary.
When to Go to the Emergency Room?
You should seek emergency care if you experience severe pain, swelling, or an inability to move the foot following an injury, as this could indicate a fracture or dislocation.
What Recovery Really Looks Like?
Initially, you will need to keep weight off the foot for several weeks. Gradual movement and physical therapy will be necessary to regain function. Full recovery, including returning to normal activities, may take up to 6 months.
What Happens If You Ignore It?
Ignoring subtalar joint problems can lead to worsening pain, reduced mobility, and further joint damage. Without treatment, these conditions can significantly impact quality of life.
How to Prevent It?
While some causes of subtalar joint degeneration are unavoidable, using proper footwear, managing conditions like arthritis early, and avoiding excessive stress on the joints can help prevent the need for surgery.
Nutrition and Bone or Joint Health
Maintaining bone health is crucial for recovery. A diet rich in calcium and vitamin D, along with maintaining a healthy weight, can support joint function and promote healing after surgery.
Activity and Lifestyle Modifications
After surgery, you may need to modify certain activities to accommodate the loss of motion in the subtalar joint. Low-impact activities like swimming or cycling may be recommended to maintain fitness without stressing the joint.
Dr. Mo Athar
