Hallux Rigidus (Arthritis big toe)
Hallux rigidus or stiff big toe is a form of early arthritis of the main joint of the big toe in the ball of the foot. The joint is stiff usually because there is scarring of the lining of the joint (capsule) coupled with extra bony spurs that form around the joint and also loss of the shock absorbing lining of the joint (articular cartilage).
Bone spurs are the body’s response to an unhappy or unstable joint. Just like we may put stabilisers onto a child’s bicycle to stabilise them, bone spurs are the body’s way of preventing further damage to the joint. The child with a slower bicycle may be upset because they have been slowed down, and we as adults with a stiff big toe are equally unhappy, usually because its painful and stiff.
Why is Hallux Rigidus painful?
The reason for pain are several. It might be that the soft tissue lining of the joint (the synovium) is inflamed or it might be that areas of bone are rubbing or impinging on other areas of bone, or indeed a combination of these reasons.
What causes Hallux Rigidus?
In most people there is no clear or obvious cause. It might be that you have a genetic predisposition to arthritis but this is not always the case. If it is the symptoms usually affect both feet. It might be simply a biomechanical issue largely because the big toe joint is under tremendous stress in walking and running and this simply wears out over time. With each step, a force equal to twice your body weight or more passes through this very small joint.
Another cause is injury. Perhaps you stubbed your toe when much younger or dropped a weight onto it. The problem may not manifest until many years later when the joint starts to wear away. Other causes of joint damage is inflamatory arthritis, such as rheumatoid arthritis, gout or pseudogout. Even more uncommonly infection could be the cause.
What symptoms does Hallux Rigidus cause?
The commonest problem is pain in the big toe joint especially when the toe is bent upwards (dorsiflexion) beyond the realms of comfort or where the joint wants to move.
Stiffness is also a common problem and a bony bump (“osteophyte” or “dorsal bunion”) may develop on top of the joint. The bump may rub on the shoes. In some people this is their only problem.
Because of the painful big toe some people tend to change their walking pattern subconsciously and walk on the side of the foot. This may produce pain in the ball of the foot or down its outside border.
Sometimes the joint also has deformity (hallux valgus).
What is the prognosis of Hallux Rigidus?
It is well known that hallux rigidus may begin early in life, even in the teens. The reason is unknown but the theories are listed above.
Although the symptoms are likely to persist or get steadily worse in the big toe, you are NOT more likely to get arthritis in other joints, such as your hips and knees, than anyone else, unless you have a genetic predisposition or an underlying inflammatory or metabolic problem.
Research shows that although the joint remains arthritic and stiff, it tends not to get much worse in the majority of people. Even after 20 years the joint was much the same as it had been when the people who were studied first went to the doctor.
However, in about 20-25% the joint becomes progressively more stiff or painful and treatment may be required.
How is Hallux Rigidus diagnosed?
Diagnosis is made clinically by a doctor who notices the joint is stiff and in many cases by Xrays which show the joint space is narrowed and extra bone spurs are present. Less commonly the diagnosis is made on MRI scanning or standing CT scans.
Treatment for Hallux Rigidus?
As with all conditions there are non-operative or operative options.
Non-Operative management of Hallux Rigidus
Activity avoidance is usually the best treatment. People who wear leather shoes often will notice that the crease of the shoe over the big toe is less obvious on the side affected by hallux rigidus than the opposite non affected side.
Because the joint is usually most painful when the toe is bent upwards during walking, it sometimes helps to stiffen the sole of your shoe so that it does not bend around the big toe. If you do this, you may need a small “rocker bar” on the sole of your shoe so that you can rock over this while walking instead of bending your toe up. This can be done for you by an orthotist, podiatrist, or chiropodist. You can also buy commercially available trainers and shoes with a built in rocker sole, such as MBT, or Sketchers.
You can take simple pain killers for the pain if it is bad and interfering with your life. Try paracetamol first as side-effects are rare at the correct dosage. If this does not work your doctor may prescribe stronger pain killers or anti-inflammatory medicines if these are considered to be safe for you.
If the toe remains very painful, it may be worth injecting some steroid mixed with local anaesthetic into the joint. This reduces the inflammation of the lining of the joint. The injection is usually performed under ultrasound control by a radiologist. An injection can last anything from 18 minutes to 18 months depending on your circumstances and should be discussed with your doctor so they can predict the likelihood of success. Remember the injection does not cure the problem, but settles down the symptoms.
Operative Management of Hallux Rigidus
If none of the above treatments help, you may consider surgery. You would be best off discussing this with an orthopaedic foot and ankle surgeon. There are five main operations for hallux rigidus:
Cheilectomy: If there are large bone spurs on the top of the joint, then removing these can help improve the range of motion and reduce the pain. This involves trimming the bone on the top of the toe and is called a cheilectomy. Most people who have a cheilectomy get less pain and a useful improvement. In about 75% this improvement is long term. If there is arthritis in the rest of the toe and in particular between the big toe bone and the sesamoids (pea shaped bones that sit under the big toe) then a cheilectomy usually will not work and can make symptoms worse.
Joint Fusion: In young fit people, especially those doing heavy jobs, a fusion of the joint is recommended. This removes the painful joint and stiffens it completely and gets rid of the pain in nearly all patients. However, the toe is stiffer than before and the choice of shoes is more limited, in particular high heels in females. A few people will go on to get arthritis of the small joint in the middle of the toe after a fusion, but this is not usually a problem. Lleyton Hewitt, the International Tennis player had his big toe fused in 2012 and continues to play tennis.
Joint Replacement: There are a number of joint replacements available, although they are only appropriate in certain patients. As with all joint replacements, there are risks with the procedure. In particular there is a risk that the new joint may loosen or wear out, or develop bone cysts around it. If these complications occured then revision would be a more complex procedure and can leave you worse off. Details should be discussed with your surgeon.
Partial Joint Replacement: There is a newer procedure known as Cartiva Synthetic Cartilage Implant (SCI) which is made from polyvinyl alcohol (PVA), a material that has a long track record in clinical use. The Cartiva SCI resurfaces just one side of the joint and places what looks like a “wine gum” into the end of the metatarsal head to give back shock absorbing capacity to the toe. Cartiva SCI has been approved for use outside the United States since 2002 and is available in Europe, Canada and Brazil. Over 4,000 implants have been used to date and a recent FDA study was reported by the company on 197 patients across 12 centres (in the UK led from the Royal National Orthopaedic Hospital NHS Trust). The study suggests that Cartiva SCI is as safe and effective as toe fusion, the gold standard treatment. What is not known is the long term results of Cartiva SCI. It is also important to understand that the study was carried out in straight toes with hallux rigidus and not toes with hallux valgus. In toes with hallux valgus it is unlikely to work.