Ankle Arthrodesis

Overview

Ankle arthrodesis is a frequent therapy for people suffering from end-stage ankle arthritis (ESAA). Ankle arthrodesis surgery aims to achieve bone union between the tibia and talus with sufficient alignment, neutral dorsiflexion, and mild outward rotation positions) in order to give a pain-free plantigrade foot for weightbearing activities.

There are several variants in surgical technique, including various approaches (open or arthroscopic) and fastening systems (internal or external fixation). Each strategy has benefits and drawbacks. Several factors can influence the success of ankle arthrodesis, including patient selection, surgeon expertise, patient comorbidities, and surgical care.

However, in our experience, the vast majority of patients with end-stage ankle arthritis have positive clinical results. This post will examine both open and arthroscopic ankle arthrodesis, as well as the indications and goals of arthrodesis for the treatment of patients with end-stage ankle arthritis.

What is Ankle arthrodesis?

Ankle fusion is a surgical procedure that combines the bones of your ankle into a single piece. Ankle arthrodesis is another name for it. The two most popular operational therapies for end-stage ankle arthritis are ankle arthrodesis and ankle arthroplasty (ESAA). Recent clinical evidence shows that ankle arthroplasty outperforms ankle arthrodesis in terms of functional results. Ankle arthroplasty, on the other hand, is associated with a greater prevalence of postoperative problems and revision procedures.

Despite the growing popularity of ankle arthroplasty, a comprehensive database shows that ankle arthrodesis is still the most often used surgical therapy for ESAA.

The tibiotalar joint is another name for the ankle joint. It's where the shinbone (tibia) lies on top of the talus, a foot bone. The subtalar joint is also part of the ankle. This is where the talus and calcaneus bones of the foot connect.

Arthritis might damage these two-foot joints. The smooth cartilage on the surface of the bones wears away over time. This causes joint discomfort, inflammation, and edema.

Ankle fusion is a surgical procedure that joins two or more bones in the ankle. This alleviates the discomfort and edema. To work on the joint, the surgeon will create an incision in your ankle. After that, he or she will compress the bones and secure them with plates, nails, screws, or other hardware. A bone transplant may also be used by your doctor to help the bones heal together.

There are several surgical procedures for ankle arthrodesis, including open and arthroscopic treatments. Although both treatments can result in excellent therapeutic outcomes, documented outcomes have varied and are contradictory. 

The variations in procedures, surgeon expertise, patient selection and demographics, and outcome assessments used all contribute to the heterogeneity in results following arthrodesis. Ankle arthrodesis should be used with caution in young patients, athletes, and those with advanced foot and ankle deformity.

Why might I need ankle fusion?

Ankle arthrodesis is recommended for individuals with ESAA who have failed at least three months of conservative therapy. Ankle arthrodesis is intended to give a pain-free plantigrade foot during weight-bearing activities. Following ankle arthrodesis, the alignment must be mild valgus (0°-5°), neutral dorsiflexion, and somewhat external rotation. Equinus ankle joint position can accompany genu recurvatum, and a varus hindfoot posture can produce painful callosities on the lateral forefoot, causing hindfoot discomfort.

Furthermore, the surgeon should make every effort to reduce limb length disparities (less than 2.5 cm or 1.0 inches). Differences in limb length can cause asymptomatic malalignment with an altered walking pattern.

Patients with little to no joint deformity (less than 15° of varus or valgus in the coronal plane) are usually candidates for arthroscopic ankle arthrodesis. Open arthrodesis is most appropriate for individuals with moderate to severe deformity because it provides better visibility for malalignment correction.

Furthermore, because fusion of the ankle joint will surely result in a loss of mobility, pre-operative forefoot balance is critical. As a result, a careful inspection of forefoot balance is required, with no excessive pronation or supination. The authors would choose arthroscopic or open debridement with subsequent external fixation in patients with substantial malalignment, comprising skin, limb discrepancies, and active/previous infection.

Patients who have severe ankle arthritis and have failed non-surgical therapies may be candidates for ankle arthrodesis. Many patients may find relief from the discomfort of ankle arthritis by using:

• Anti-inflammatory medication (such as ibuprofen)
• Injections of steroids into the ankle joint
• Modification or limitations of activity
• Walking aids (such as canes)
• Specialty braces that stabilize the ankle and restrict its movement
• Cushioned and specially contoured shoes

These therapies have no effect on reversing ankle arthritis. They may give temporary or permanent pain relief to many people. If these methods do not give appropriate pain relief or function, the patient may be a candidate for ankle fusion. You should talk to your foot and ankle orthopedic surgeon about your options.

Patients should avoid ankle arthrodesis if they have:

• Inadequate bone amount or quality for fusion
• Inadequate blood flow to the ankle
• Nerve function is severely reduced.
• Medical conditions that enhance anesthetic risk
• A severe limb malformation

Types of Ankle arthrodesis

There have been several surgical procedures documented for ankle arthrodesis. The approach should be chosen based on the patient's features, function, and treatment aim, as well as the surgeon's choice.

Approach to ankle arthrodesis

The method of ankle arthrodesis is widely classified as open or arthroscopic. The front approach, posterior approach, lateral approach, medial approach, and combined medial and lateral approach are all subsets of the open method. The fundamental advantage of an open technique over an arthroscopic method is that it is easier to rectify malalignment and place plates and bone grafts.

However, because of the substantial quantity of soft tissue dissection necessary, open arthrodesis is linked with a greater likelihood of wound complications. As a result, hospitalization and recuperation times may be extended. As a result, open techniques are often reserved for individuals with moderate to severe ankle abnormalities who have good skin.

Arthroscopic ankle arthrodesis is a less invasive surgery that allows for a shorter operational time and similar union rates. Although anterior ankle arthroscopy is the most often used technique for this treatment, current research suggests that posterior ankle arthroscopic arthrodesis may yield improved fusion rates.

Arthroscopic ankle arthrodesis is recommended for patients who have a modest ankle joint deformity (less than 15° of varus or valgus in the coronal plane) or who are at a higher risk of wound complications (e.g., immunosuppressed, diabetics, rheumatoid arthritis patients). Although arthroscopic arthrodesis is becoming more popular, open ankle arthrodesis is still the most often used surgery for ESAA in the United States of America. 

Fixation methods

In ankle arthrodesis, both internal and external fixation may be employed. Each has distinct benefits, with good outcomes proven with both fixation systems.

Internal fixation techniques such as screws, plates, and retrograde intramedullary nails have all been documented. Many surgeons favor screw fixation as the principal method of internal fixation because screws are simple to employ, have minimal morbidity (requiring just tiny percutaneous incisions), and are less expensive than most other procedures. However, screw fixation has been associated with greater nonunion rates of the ankle joint, particularly in osteoporotic bone.

Plates are helpful for ankle arthrodesis because they provide several alternatives. The surgeon has options about the type of plate required (e.g., conventional or locking), the number of plates required, and where the plates should be placed. While some surgeons favor plates because they are tougher than screws and may achieve greater union rates, the substantial dissection required to implant the plate might increase the risk of infection and morbidity.

Plates and screws can also be used together. Recent biomechanical research discovered that combining plate and screw attachment offered substantially more rigidity than either plates or screws alone. There was no significant difference in this trial between three compression screws, an anterior plate, and a lateral plate fixation.

Retrograde intramedullary arthrodesis is generally reserved for ankle and subtalar joint arthrodesis. Subtalar arthritis is commonly seen in patients with ESAA. It's difficult to tell if the discomfort is originating from the tibiotalar joint, the subtalar joint, or a mix of the two in these patients.

The surgeon must establish this before surgery since it is preferable to avoid subtalar joint arthrodesis wherever feasible, especially when the ankle will be fused. The subtalar joint is crucial for gait stability in the setting of tibiotalar arthrodesis. When joint mobility is permanently limited post-arthrodesis, the subtalar joint allows for ankle joint inversion and eversion, which helps compensate for a more stable gait.

External fixation is usually recommended for difficult patients with severe bone abnormalities, limb length disparities, poor bone quality, and active or past infection. Overall, external fixation union rates and outcome indicators are lower than internal fixation.

How do I prepare for ankle fusion?

Discuss how to prepare for your operation with your healthcare practitioner. Inform your doctor about all of the medications you are taking. Aspirin and other over-the-counter medications fall into this category. Some medications, such as blood thinners, may need to be stopped ahead of time. If you smoke, you must quit before your operation. Smoking might cause a delay in recovery. If you need assistance quitting smoking, speak with your healthcare professional.

Imaging examinations may be required prior to surgery. CT scans, ultrasounds, X-rays, and magnetic resonance imaging are among examples (MRI(

The night before your procedure, don't eat or drink anything after midnight. Inform your doctor about any recent changes in your health, such as a fever.

You may need to make some modifications at home to aid your recovery. This is because you won't be able to walk properly for a time. Make arrangements to have someone drive you home from the hospital.

What happens during ankle arthrodesis?

Your healthcare professional can assist you in understanding the specifics of your procedure. Your ankle fusion will be performed by an orthopedic surgeon with the assistance of a team of experienced healthcare experts. The entire procedure might take many hours. In general, you should expect the following:

• You may have spinal anesthesia. This is done to ensure that you don't feel anything from your waist down. Sedation will very certainly be administered to you to help you relax. You might also be given general anesthesia. This will relieve your pain and allow you to sleep through the procedure.
• During the procedure, a healthcare expert will monitor your vital indicators, such as heart rate and blood pressure.
• The surgeon will make an incision through your ankle's skin and muscle, as well as maybe another on your foot. The surgeon will create a smaller incision if you get minimally invasive surgery. He or she will then assist with the procedure by using a small camera with a light.
• Any remaining cartilage in the afflicted joint will be removed by your surgeon. He or she will use hardware to attach the bones in the correct location.
• Any further repairs that are required will be performed by your surgeon.
• Stitches or staples will be used to close the layers of skin and muscle surrounding your ankle and foot.

Biologics

Biologics can be used to help in ankle fusion in both open and arthroscopic procedures. There are now two categories of biologics available: osteoconductive and osteoinductive agents. Osteoconductive agents, which include bone allografts, demineralized bone matrix, and other apatitic pastes, act as a scaffold at the site of fusion.

This scaffold functions as a tissue network, allowing autologous cell contact for osteogenesis. Osteoinductive agents, such as bone morphogenetic proteins, platelet-rich plasma, or concentrated bone marrow aspirate, are substances that promote osteogenesis directly.

This might be in the form of growth factors (platelet-rich plasma) or stem cells (concentrated bone marrow aspirate) to induce osteoblast development. Before and after the final screw placement, biologics should be injected into the fusion site.

What happens after an ankle fusion?

Discuss your post-surgery expectations with your healthcare physician. When you wake up, your leg will most likely be lifted and immobilized with a brace. As soon as you are able, you can resume your usual diet. You may require follow-up X-rays to see how well your operation went. You will most likely need to stay in the hospital for a few days.

You may have significant discomfort immediately following your procedure. Pain relievers may be useful in relieving your discomfort. The soreness should subside in a few days. It may be beneficial to rest and elevate your leg as much as possible immediately following surgery.

It is critical to maintain the fused ankle elevated during the first postoperative period to reduce edema. Ideally, this implies laying down or sitting in a reclining position with the ankle elevated over the heart. For this brief duration, pain medication is offered.

It will take at least 6-8 weeks for the tibia and talus to fuse sufficiently for patients to bear weight on their surgical leg. It might take up to 10-12 weeks. Most patients find it difficult to go about their regular lives without putting weight on one leg. Crutches, walkers, wheelchairs, or knee scooters are commonly used by patients. Prior to surgery, it may be beneficial to work with a physical therapist.

It is beneficial to have someone available to assist with basic duties and activities at home, particularly during the first two weeks. A patient's house should be properly prepared. Stairs may need the use of ramps. Beds may need to be moved to the ground level. Shower chairs, commodes, and railings may be required.

Non-absorbable sutures or staples are normally removed 10-14 days following surgery. At this point, gentle physical treatment to maintain the other joints in the foot supple may begin. X-rays may be conducted to ensure that the alignment has not shifted. Swelling and discomfort will worsen in the first few weeks following surgery if the foot is placed below the heart for lengthy periods of time. Mild swelling and soreness may linger for months when the foot is placed below the heart for extended periods of time but will subside over time.

Patients gradually begin putting weight on their ankles using a walking boot when a significant amount of time has passed. X-rays may be taken to ensure that the ankle is fusing properly. This transition will be aided by physical treatment. After 10 to 12 weeks, the ankle fusion is usually strong enough to enable walking out of the plastic boot and a gradual return to more strenuous activity.

You will most likely need to wear a splint for a few weeks after your operation. You may also be required to wear crutches for many weeks. As you recuperate, your healthcare practitioner will give you advice on how to move your foot. For a few months, you won't be able to put your whole weight on it.

Initially, you will be unable to view your incision. However, notify your healthcare practitioner immediately away if the discomfort at the incision site worsens, or if you develop a fever or chills.

Make every effort to keep all of your follow-up appointments. This is done so that your healthcare professional can monitor your development. A few weeks following surgery, your splint may be replaced with a cast or boot. This cast will most likely take off several weeks following your operation. Physical treatment may be required for a few months. This is to help you maintain your ankle and leg strength. It might take many months before you can resume all of your typical activities.

Once the ankle has fused, it is quite strong. On fused ankles, many patients have physically demanding occupations, travel long distances, hike, cycle, and ski. However, the fused ankle will never function exactly like a natural ankle. Patients are urged to discuss their individual goals for activity resumption with their foot and ankle orthopaedic surgeon. Running and other comparable activities are not advised.

Postoperative rehabilitation

For 6 weeks, the ankle joint is immobilized in a non-weight-bearing leg cast. The cast is subsequently removed, and the patient is placed in a Controlled Ankle Movement Walker Boot. Radiographs should be obtained at 6 weeks, 3 months, 6 months, and 1 year to check the location of fusion and the adequacy of the union. Weightbearing should be gradually increased by 10% every two weeks. Patients may be permitted to completely weight bear once a complete union is shown on radiography.

What are the risks of ankle fusion?

Every surgery has risks. The risks of ankle fusion include:

• Infection
• Damage to nearby nerves
• Bleeding
• Blood clot
• The bones did not join together properly
• Misalignment of the bones
• New arthritis in nearby joints (very common)

A decreased range of motion in the joint is a common adverse effect after ankle fusion. For most people, this isn't a serious issue.

Your risk of problems may differ depending on your age and overall health. For example, if you smoke or have insufficient bone density, you may be more likely to have certain issues. People with poorly managed diabetes may be at a higher risk of complications. Consult your healthcare practitioner to determine which hazards are most relevant to you.

Conclusion

Ankle arthritis is caused mostly by trauma and has a significant influence on the patient's quality of life. Ankle arthrodesis is recommended for individuals with end-stage ankle arthritis who have not responded to conservative treatment. Ankle arthrodesis is a viable therapy option for advanced arthritis. There is currently no agreement on the best technique and fixing method.

As a result, it is critical for the surgeon to grasp both the open and arthroscopic approaches, as well as when either is appropriate. Joint alignment must be somewhat valgus (0°-5°), neutrally dorsiflexed, and externally rotated. Disparities in limb length should also be kept to a minimum (less than 2.5 cm or 1.0 inches).

If these biomechanical components are not addressed, it may result in discomfort and a changed gait pattern. The significance of appropriate preoperative forefoot balance in allowing for optimal postoperative mobility cannot be overstated. Ankle arthrodesis, when done according to these principles, results in functional improvement and sufficient joint fusion in patients with end-stage arthritis.

There are other fixation possibilities, however, the authors favor two to three screws. Because of contradictory findings, it is difficult to reach a firm consensus on whether open or arthroscopic arthrodesis should be the cornerstone of treatment for ESAA. Because the present success of arthrodesis is still dependent on a range of circumstances, the current study seeks to synthesize current information for enhancing ankle arthrodesis results.