A Patient’s guide to Cartiva

What is big toe arthritis (hallux rigidus)?

Hallux rigidus is the medical term for arthritis of the big toe at joint where the big toe joins the foot (the metatarsophalangeal joint). This condition is caused by wear and tear of the joint and the cartilage which protects the joint wears out. This may affect the whole joint, or only part of it.

Anyone can get arthritis of the big toe, but it is more likely to affect those who are active and regularly participate in sporting activities. Patients may feel a lump on top of the big toe, the toe may get stiff, and there may be difficulty wearing certain types of shoes. However, the most common complaint is pain. The pain is usually worse when walking or running and with activities which cause an upward movement of the toe at the joint.

What are the treatments available for big toe arthritis?

There are a number of non-surgical options which can work well for managing big toe arthritis. These include:

Footwear modification (lower heels, wider fitting shoes, rocker soles, etc.
Insoles or other shoe inserts, such stiff orthotic
Simple analgesia (pain killers) or anti-inflammatory gel
Weight loss (if necessary
Physiotherapy to try and maintain a range of movement

If these methods are not effective then surgical procedures may be considered, and include:

Manipulation and injection of steroid

This procedure does not involve any surgical cuts but is usually carried out under local anaesthetic or sedation as a day case procedure. A manipulation is performed to release the contracture of the joint to allow more movement and reduce pain. A steroid injection into the joint also helps to reduce pain and swelling. Pain relief is obtained in about 50% of patients for up to two years but the procedure does not cure the arthritis and further treatment will be needed later.

Cheilectomy

This procedure involves removing the extra bump of bone on top of the big toe that is causing pain and discomfort. It does not cure the arthritis in the joint. By performing this operation, movement in the joint of the big toe is increased. This procedure may not work in patients with severe arthritis. For those patients with less severe arthritis, there is an 80% chance of this surgery being successful for up to five years. If a cheilectomy fails to improve your condition, then a fusion may be needed.

Fusion

This is the operation which is considered the ‘gold standard’ for treating big toe arthritis. In this operation the worn-out bits of bone around the joint are removed and the toe bones are joined together and held with screws or screws and plate. This operation is very effective at treating pain and is effective in 90% of patients long-term. However, the toe is fixed in a stiff position. This is often not a problem as the toe is usually stiff before the operation and the toe is fixed in a ‘functional’ position (this means that you can still walk effectively, and some patients can wear a low heel in their shoe). Many patients are able to return to sport after fusion, including racquet sports.

Joint Replacements / resurfacing

A number of joint replacement options have been used over the years for big toe arthritis. A joint replacement is where the worn-out bits of bone have been removed and replaced with metal, ceramic, silastic, or other implants. Because a large amount of force goes through the big toe and it is a very small joint, replacement of the big toe is not always successful and is not suitable for everyone. Many implants have been tried over the years and this is an area of ongoing research. Your surgeon will discuss with you whether a replacement is something that may be right for you. The Cartiva is a type of resurfacing, which means that only a part of the bone is removed and replaced.

What is Cartiva?

The Cartiva (Cartiva Synthetic Cartilage Implant) is a gel-like implan\t that is designed to replace the damaged cartilage surface. It is made from polyvinyl alcohol, a material that has been used in a number of medical device applications for decades, including contact lenses. In th\is procedure, only a small part of the bone is removed and replaced with the implant. The gel material acts as a cushion to prevent the worn-out bones rubbing together and aims to prevent further damage to the bone over time.

Who is Cartiva suitable for?

Cartiva is suitable for patients who have arthritis of a small joint. In the foot and ankle this is most commonly for the big toe. It was initially used and tested in patients who have ‘end-stage’ arthritis, with severe changes and stiffness. However, it may also be used in patients who have some preserved movement and where maintaining this movement is desired. It is however not suitable in a number of cases, which include

Infection
Bone loss
Very soft bone
Arthritis with deformity (for example, a bunion)

Your surgeon will discuss with you whether or not Cartiva may be a suitable option in your case.

What do you need to know about if considering Cartiva surgery?

The Cartiva implant is a relatively new device, and although it has been used in the foot and ankle for over a decade, there are few studies looking at the long-term outcomes. A large study was conducted in Canada and the UK (including at the Royal National Orthopaedic Hospital) comparing the results to fusion of the big toe.

Results compared to fusion

The results of Cartiva were found to be similar to fusion, but Cartiva was not found to be better than fusion. This includes ability of patients to return to walking and sport, where patients did equally well with fusion and Cartiva. To date the longest reported outcome for Cartiva is 5 years (this is called medium-term). This means that there is reasonable evidence to support the use of Cartiva in the short-term, but we do not know how long it will last. It does appear that the Cartiva is safe to use, however.

Preserving movement

Further work has found that Cartiva may also be effective in patients with preserved range of movement and in these cases, it may help in preserving movement. Although it is now often used for this reason, there is no evidence that these patients do better with a Cartiva than a fusion.

Failure of the implant

There are a proportion of patients in whom the device fails early (within a year of surgery). This may be for a number of reasons, but one of the most common is that the device may ‘sink’ into the bone over time \(this is called subsidence). If the Cartiva fails, then you will have to disc\uss with your surgeon what the next step is. The treatment will depend on the cause of the failure. In some select cases a joint replacement may still be possible, but the majority of patients will require a fusion.

National recommendations (NICE Guidance)

In the UK, there is a national recommendation (from NICE) that Cartiva can be used, but patients should discuss the pros and cons in detail with their surgeon and be followed up to ensure they recover well. This means that if you do have a Cartiva, you may need to be seen more frequently than if you had a fusion and may be followed-up for a number of months / years.

What does the surgery involve?

In this operation a cut is made around your big toe. Any worn out or extra bone on the top of your big toe joint is removed and the surrounding soft tissues may be released to allow more range of movement. You then have the ‘Cartiva’ device inserted. This is an 8 to 10mm impl\ant made of a similar material to contact lenses. It inserts into a small ho\le drilled into the bone and acts as a cushion when moving the toe. After the surgery the skin is closed, a dressing is applied, and you are allowed to walk in a special shoe. You will need to keep your foot elevated for the first two weeks to reduce pain, swelling, and complications, and you will need to keep the foot dry until the wounds are fully healed. Once the wounds are healed (usually by around 2 weeks) you are allowed to begin to move the joint to increase the range of movement.

How will you be followed up?

After the surgery you will be seen at 2 weeks to check the wound and remove the stitches if required. You will then usually be seen at 6 weeks to monitor your progress, and at this stage you will have an x-ray of your foot. You will then be seen at 3 months. If everything is progressing as expected, you will next be seen at one year, at which point you will have further x-rays. You will then be followed-up annually with x-rays.

At the appointments you will be asked how you are doing, what activities you can perform, and the movement of your toe will be assessed. You will also be asked to fill out some questionnaires for us to get an idea of how your health and activities have been impacted by the arthritis and your surgery. You will be asked to fill these out before your surgery and at 6 months and at 1 year. This will be sent to you electronically. As this is still a relatively new procedure, it is very helpful to us if you can fill these out, as it lets us monitor our patients more effectively.

Benefits of Surgery

This goal of this operation is to improve the pain you have around your big toe. It may also improve your range of movement.

Risks of Surgery

All operations have risks. Any medical conditions you already have may become worse due to the operation. Some risks may be rarer but more relevant to you. It is important to discuss with your surgeon your particular circumstances.

Commons Risks (up to 5 in every one-hundred forefoot surgeries

Pain - For most operations, you will be given a local anaesthetic block to reduce pain, but you may still have some pain or discomfort. Usually, this can be controlled with simple pain management tablets
Swelling - Feet tend to swell up because of gravity, and this can last for some months
Scarring - any type of surgery will leave a scar, sometime this can be painful or sensitive
Minor wound redness - with all operations there is a risk of infection. Sometimes the wound edges can become a bit red or may not fully heal. In some cases, you may require antibiotics to get this to settle. Risks are higher if you have diabetes, if you smoke, or if you are on medication which alters your immune system (e.g., steroids or rheumatoid medication)
Numbness - after surgery you may have some numbness or tingling around the scar. This is because small nerves to the skin may have been cut. This usually recovers with time, but sometimes may be permanent.
Transfer metatarsalgia - because the surgery is on your big toe, the balance across your toes can change. This can sometimes mean that pain can occur in parts of the foot that previously did not have pain. Most cases settle with physiotherapy and insoles, but further surgery might be necessary
Subsidence / Failure - This procedure allows your joint to move, but the implant may wear out over time or may sink into your bone, particularly if you have soft bone. If either of these happen, you may develop pain and may need further surgery.

Less Common Risks (occur one in every one-hundred forefoot surgeries

Blood clots - because you will be allowed to walk on your heel after the surgery blood clots are not common, but can occur, and can lead to swelling of the leg (deep vein thrombosis) or chest pain (pulmonary embolism). Please inform the team if you have had a previous blood clot or if you or a family member have clotting problems.
Arthritis - removing the bony bump on top of the toe will allow more movement in the toe joint. If there is arthritis in the rest of the joint, this increase in movement may cause an increase in your pain.

Rare Risks (occur in less than one in every one-hundred forefoot surgeries

Deep infection - Although every precaution is taken to prevent infection, it can still happen. If the infection does not settle with antibiotics, you may need a further operation to remove any metal and clear the infection
Intraoperative fracture - rarely a fracture may occur during surgery. The surgeon will act in your best interests at the time of surgery to give you the best outcome
Complex regional pain syndrome - this is where the “fight or flight” nerves that supply the foot become overactive and this can cause swelling, stiffness, pain, and colour and temperature changes to the foot. Treatment involves physiotherapy and other treatments, and it could take several months to improve
Nerve injury - if a larger nerve supplying the toe / foot becomes damaged or caught in scar tissue, it could lead to ongoing pain, numbness, and tingling. Such damage is usually temporary, and the sensation returns over some time, but it can be permanent
Tendon injury - during the operation, a tendon may be injured or can become caught in the scar leading to reduced movement. Rarely this requires further surgery
Blood vessel damage - if the blood supply to a toe is damaged it could lead to part or all of the toe becoming permanently damaged. In severe cases, the damaged parts of the toe may need to be removed
Loss of toe - although extremely rare, loss of toe can result from surgery especially if there is deep infection or a blood vessel injury. The risk for this complication is increased in diabetics and smokers
Death - whilst this is extremely rare for foot and ankle surgery, it can occur especially if there are pre-existing medical conditions.

If you would like this leaflet translated into another language/large print, please contact the Quality Team on 02089095439.

Royal National Orthopaedic Hospital NHS Trust
Brockley Hill
Stanmore
Middlesex HA7 4LP
Email: rnoh.footandankle@nhs.net
Telephone: 020 3947 0050
www.rnoh.nhs.uk