Akshay Oswal1, Sanat Phatak2
1:Musculoskeletal physiotherapist, Rehab Clinic, Gaffar Baig street, Camp, Pune
2: Associate Consultant Rheumatology, KEM Hospital Research Centre, Pune
Rheumatoid arthritis is a chronic disease that attacks multiple joints throughout the body. It most often starts in the small joints of the hands and feet, and usually affects the same joints on both sides of the body. More than 90% of people with rheumatoid arthritis (RA) develop symptoms in the foot and ankle at some time during the course of the disease.
In what ways can rheumatoid arthritis affect your foot?- it may not always be arthritis.
- The joints of your body are covered with a lining ( synovium) that lubricates the joint and makes it easier to move. Rheumatoid arthritis disease activity makes your immune cells attack this lining, and it swells and becomes inflamed. This is the earlies form of involvement, called synovitis.
Treatment at synovitis stage prevents complications and has the best long-term outcomes. - If the joint remains inflamed for a long time, this can lead to gradual destruction of the destroying the joint, as well as the ligaments and other tissues that support it. Weakened ligaments, and joint destruction, can cause joint deformities — such as claw toe or hammer toe.
- Rheumatoid arthritis can cause softening of the bone (osteopenia) can result in stress fractures
and collapse of bone. The arch of your foot can be lost and walking can be painful. - Rheumatoid deformities change the mechanics of your foot. ‘Normal’ pressure points are not used, and your body weight is borne by areas not designed to support friction. This produces callosities and corns.
- In severe, untreated cases rheumatoid arthritis disease activity itself may lend itself to produce hard and occasionally painful swellings, called ‘rheumatoid nodules’. These may interfere with footwear and mobility.
- Rheumatoid arthritis can affect blood vessels in severe cases (rheumatoid vasculitis). This can lead to gangrene of the digits, making toes become black and hard. In addition, it may involve nerves of the foot, leading to tingling, numbness or loss of sensation.
Symptoms differ according to the area of the foot involved
Ankle: Difficulty with inclines (ramps) and stairs are the early signs of ankle involvement. As the disease progresses, simple walking and standing can become painful.
Hindfoot (Heel Region of the Foot): The main function of the hindfoot is to perform the side-to-side motion of the foot. Difficulty walking on uneven ground, grass, or gravel are the initial signs. Pain is common just beneath the fibula (the smaller lower leg bone) on the outside of the foot. As the disease progresses, the alignment of the foot may shift as the bones move out of their normal positions. This can result in a flatfoot deformity. Pain and discomfort may be felt along the posterior tibial tendon (main tendon that supports the arch) on the inside of the ankle, or on the outside of the ankle beneath the fibula.
Midfoot (Top of the Foot): With RA, the ligaments that support the midfoot become weakened and the arch collapses. With loss of the arch, the foot commonly collapses and the front of the foot points outward. RA also damages the cartilage, causing arthritic pain that is present with or without shoes. Over time, the shape of the foot can change because the structures that support it degenerate. This can create a large bony prominence (bump) on the arch. All of these changes in the shape of the foot can make it very difficult to wear shoes.
Management
1.Medications for rheumatoid arthritis: Active inflammation needs optimum disease modifying therapy. Drugs such as methotrexate, leflunomide, sulfasalazine and newer biologic agents such as rituximab or adalimumab may be required. Your treating rheumatologist is in the best place to decide whether DMARD therapy is optimum.
2.Symptomatic therapy: Nerve involvement may not respond to DMARD alone. Therapies such as pregabalin or amitryptiline may reduce neurological pain. In cases of vasculitis, high dose steroid and blood thinners may be added.
3.Physical therapy :The benefits of physical therapy interventions in Rheumatoid Arthritis foot involvement are paramount. Physiotherapists help patients cope with chronic foot pain and disability through the design of programs that address flexibility, endurance, aerobic condition, a range of motion (ROM), strength, bone integrity, coordination, balance and risk of falls.
Treatment techniques employed depend on the phase of the illness. In acute phase of the illness, Cold/Hot Applications: cold for acute phase; heat for chronic phase and used before exercise.
Transcutaneous electrical nerve stimulation (TENS) is used to relieve pain. Hydrotherapy-
Balneotherapy: exercise with minimal load on the joints.
Joint Protection: Rest & Splinting, Orthosis and splinting prevent the development of deformities and support joints
Therapeutic Exercise : Physical exercise helps to increase the physical capacity of the patient and strengthens muscles around the joint. Exercise is NOT detrimental to disease activity or pain in RA. Exercise therapy is aimed of improving daily functioning and the social participation by means of improvement of the strength, aerobic condition, range of motion, stabilization and coordination.