Problems in the ankles and heels
Pain in the ankles and heels can come from joints themselves, or from muscles and tendons around the joints. Osteoarthritis isn't very common in the ankle but can be the result of previous damage from an injury or due to inflammatory arthritis.
When inflammatory arthritis affects the ankle, the joint may be sore or stiff first thing in the morning or after sitting for a while.
Valgus heel is commonly associated with tendon damage on the inside of the ankle and arch; this can cause the heel to drift outwards which is known as valgus heel. It may not cause problems if it doesn't drift too far, but it can be troublesome if the arch flattens. It's fairly common in people with rheumatoid arthritis and research has shown that early treatment of rheumatoid arthritis may slow the development of valgus heel.
Plantar heel syndrome
Also known as plantar fasciitis, this is a degeneration and/or inflammation at the heel, where tendons and fascia that attach under the heel bone cause pain. It used to be
known as policeman's heel and is the most common cause of discomfort around the heel. Plantar heel syndrome frequently affects people aged 40 to 50 with active occupations. It can be associated with inflammatory arthritis.
Research has shown that plantar heel syndrome is sometimes caused by the shortening of the Achilles tendon. Ask your doctor or physiotherapist about exercises to help you lengthen it. Losing weight and wearing insoles to provide cushioning in your shoes may ease symptoms. A steroid injection can help but they're not recommended as a first resort.
Also known as Achilles tendinitis, this is an inflammation of the Achilles tendon at the back of the ankle. It can occur as an over-use injury in people who take part in excessive exercise or exercise they're not used to (for example, marathon runners). It can also affect people who have psoriatic arthritis, reactive arthritis or ankylosing spondylitis.
Changes in the structure of the arch
The arches of the feet allow the weight of the body to be spread over many bones and joints. The arch structure can change when it's affected by arthritis, and the structures nearby can be strained. In mild cases this feels like tiredness in the arch area, but it can be more painful if the muscles or tendons are overworked.
Losing weight if you're overweight can help ease symptoms because it reduces the stress on joints. Swimming is a good form of exercise if you find weight-bearing exercise difficult. Some people find arch supports or foot orthoses helpful for arch pain or tiredness.
Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can help with arch pain, and a steroid injection may ease severe pain. You may find an anti-inflammatory gel applied two to three times per day can help. You can buy this in chemists and supermarkets. Anti-inflammatory tablets should be taken when a number of joints are painful.
Having higher arches (pes cavus) may increase your chances of developing other problems such as hammer toes, bunions, corns or calluses. Lower arches (pes planus) are sometimes linked to leg problems, especially knee cap pain.
Problems in the ball of the foot
Pain can be caused by arthritis in the joints at the ball of the foot, especially if you have arthritis elsewhere. However, most pain in the ball of the foot comes from minor damage to the soft tissues – tendons, bursae, fat pads, nerves and skin.
The most common causes of discomfort under the ball of the foot are calluses (a build-up of hard skin) and corns. Calluses form at areas of high pressure or friction and typically cause a burning pain. If the pressure on the callus is extremely high, small areas of skin within the callused area produce an abnormal type of skin tissue, leading to the formation of a corn.
Calluses will grow back in four to six weeks unless the pressure or friction that caused it is removed by changing to softer or roomier footwear or by inserting cushioning pads.
Other problems that can occur in the ball of the foot include:
Bursae are pockets of fluid that cushion joints and tendons. They can become inflamed under the ball of the foot and cause pain, particularly if wearing high heels or tight shoes, or by doing too much weight-bearing exercise.
People with rheumatoid arthritis often develop new and large bursae under the ball of the foot. Bursae can grow and shrink as the level of inflammation varies. They also occur next to large bunions or other irritated joints. Treatment for an inflamed bursa starts with reducing the pressure on the area. If it's large, especially inflamed or you've had it for a long time it may help to have fluid drained and a steroid injection.
A neuroma is a thickening of a nerve, which occurs when it rubs against other internal tissues. It's most common at the base of the toes, often between the third and fourth toes. The symptoms are sudden pain and/or tingling in the toes.
A neuroma should settle down with more roomy footwear, but special insoles or pads under the area may help. These may be available through an Health and Care Professions Council (HCPC)-registered podiatrist or orthotist. A local steroid injection may be recommended and, if symptoms are severe, the thickened nerve may be surgically removed.
In rheumatoid arthritis, firm, pea-sized lumps can occur at pressure points such as the big toe joints, the back of the heels or on the toes. Nodules on the soles of the feet can be particularly uncomfortable. Padding can ease the discomfort but, in some cases, the nodules may need to be removed surgically.
Problems in the toes
Bunions are bony lumps that develop on the side of the foot at the base of the big toe. A bursa may develop here too, especially if shoes press against the bunion. The bursa may become inflamed and painful.
Sometimes as the bunion develops, the big toe may be pushed over towards the smaller toes. The big toe joint becomes stiff and its range of movement is reduced sometimes without the bony lump. This is called hallux rigidus. This can cause the other toes to become clawed or permanently bent (known as hammer toes).
Symptoms of a bunion can be controlled by choosing shoes with a soft, wide upper to reduce pressure and rubbing on the joint. Insoles (orthotics) can help control the foot function to relieve pressure on a painful joint. Bunion pads are available from chemists if you have a flare-up of a bunion or bursa. If symptoms persist over a long period, the bunion may need to be surgically removed.
Hammer toes (also known as claw toes, mallet toes or retracted toes) are toes that are permanently bent. Hammer toes occur because of problems with the tendons inside the foot or because toes are squashed by poorly fitting shoes and/or socks.
Hammer toes are most common in people who have bunions or high-arched feet. Discomfort from hammer toes is usually due to a build-up of hard skin over the raised joints, resulting in corns and calluses. There's a slight risk of ulceration.
Mild cases may be helped by rubber, leather or silicone splints. Pain from corns and calluses may be eased by choosing shoes with a more generous fit or softer uppers, or by using a protective pad over the painful area. The only way to correct hammer toes is with surgery.
Rheumatoid arthritis, lupus, scleroderma and diseases such as diabetes that affect the bones, circulation and nerves can cause ulcers (delayed healing and foot sores).
Ulcers on the toes and feet can be problematic in people with rheumatoid arthritis and scleroderma, where the circulation is compromised due to Raynaud's phenomenon. If you discover an open sore that won't heal, speak to your specialist rheumatology team at the hospital, which may include a nurse specialist and an HCPC-registered podiatrist, or a GP.
If you're on steroids or biologics, it's important to treat ulcers as soon as possible because your risk of infection is greater. Ulcers which have become infected may require treatment with antibiotics. Medications to improve the blood flow can help.