Midfoot arthritis is a common disease in adults. Midfoot is very crucial to the overall function of the foot. It is made up of 5 tarsals that help to transfer the weight from the ankle to the forefoot. They also provide the necessary push from the ankle for foot movement. These small bones are kept in place by the midfoot cartilage. Any damage to this cartilage results in friction between these which results in pain and deformation of foot and ultimately midfoot arthritis.
The main cause of midfoot arthritis is the damage of the cartilage which can occur due to:
Degeneration of midfoot cartilage could be the result of an injury or a fracture. It occurs due to the gradual “wear and tear” during walking. this degeneration is common in overweight and obese individuals as their weight puts more pressure on the cartilage and it gets prone to degeneration.
Midfoot arthritis can also occur due to the inflammation of cartilage due to autoimmune response as in rheumatoid arthritis. This causes the cartilage to become stiff and is unable to hold the tarsals together, resulting in midfoot arthritis.
Midfoot arthritis is characterized by following symptoms:
The most common symptom of midfoot arthritis is pain. It is worsened by walking as the tarsals rub past each other producing friction. Pain is experienced after a long period of standing or taking the first few steps in the morning. There is also a bony prominence in the midfoot due to the moving of tarsals from their place.
In midfoot arthritis caused by inflammation of cartilage, the fluid from the synovial membrane is retained in the place of cartilage. This fluid retention or dislocation of tarsals can result in swelling that leads to unbearable pain.
Due to the loss of cartilage, there is no cushioning provided to the tarsals and they keep past each other every time the foot is moved. The friction produced ultimately results in decreased flexibility and stiffness. If left unchecked and not taken care of, it can result in complete foot immobility.
Midfoot arthritis can be diagnosed through physical examination and through image scanning
- Physical examination:
During the physical examination the physio examines the part of the foot that aches upon the application of certain pressure. It reveals the swelling in the foot and checks if there is any tenderness in the midfoot region. A bony prominence can also suggest midfoot arthritis.
- X-rays and CT scans:
Imaging through x-rays and scans shows the joints of the foot that have been misplaced. The absence of cartilage will leave some gaps between the tarsals on the x-ray. The tarsometatarsal joint (midfoot joint) is the most commonly affected joint.
Pain relief/ medication:
- For pain relief paracetamol can be used.
- With the approval of a personal physician, non-steroidal anti-inflammatory drugs (NSAD) like brufen can be taken for inflammation.
- Physiotherapy and foot massages help in reducing foot pain.
- Steroid injection in the affected joints might help in temporary pain relief.
There are 2 types of treatment for midfoot arthritis. Operative and non-operative.
- non-operative treatment:
Exercise is a natural remedy for arthritis in general. Non operative treatment primarily includes the changing in lifestyles like:
- losing weight with non-weight bearing exercises.
- Wearing shoes with stiff insoles and softer upper to reduce the force required to walk. Not tying the shoelaces too tightly.
- Resting when necessary.
- Use of supporting shoes and walking sticks to reduce pressure on the midfoot.
Operative treatment of midfoot arthritis is the midfoot fusion. It is also referred to as arthrodesis. The primary goal of this process is to reduce the motion between the joints and help improve the function of the foot.
During this surgery, the 5 tarsals that make up the arch of the foot are fused together by placing hot metal screws and shafts to immobilize the small bones. These small tarsals then align to form one mass of bone. As there is no space between them, no movement; and hence no friction. The protruding bone from the foot goes back as well.
Out of 100, 92 midfoot surgeries go successful and people are relieved from arthritis.