Osteoarthritis of the Foot and Ankle

What Is Osteoarthritis?
Osteoarthritis is a condition characterized by the breakdown and eventual loss of cartilage in one or more joints. Cartilage (the connective tissue found at the end of the bones in the joints) protects and cushions the bones during movement. When cartilage deteriorates or is lost, symptoms develop that can restrict one’s ability to easily perform daily activities.

Osteoarthritis is also known as degenerative arthritis, reflecting its nature to develop as part of the aging process. As the most common form of arthritis, osteoarthritis affects millions of Americans. Some people refer to osteoarthritis simply as arthritis, even though there are many different types of arthritis.

Osteoarthritis appears at various joints throughout the body, including the hands, feet, spine, hips, and knees. In the foot, the disease most frequently occurs in the big toe, although it is also often found in the midfoot and ankle.

Causes
Osteoarthritis is considered a “wear and tear” disease because the cartilage in the joint wears down with repeated stress and use over time. As the cartilage deteriorates and gets thinner, the bones lose their protective covering and eventually may rub together, causing pain and inflammation of the joint.

An injury may also lead to osteoarthritis, although it may take months or years after the injury for the condition to develop. For example, osteoarthritis in the big toe is often caused by kicking or jamming the toe, or by dropping something on the toe. Osteoarthritis in the midfoot is often caused by dropping something on it, or by a sprain or fracture. In the ankle, osteoarthritis is usually caused by a fracture and occasionally by a severe sprain.

Sometimes osteoarthritis develops as a result of abnormal foot mechanics such as flat feet or high arches. A flat foot causes less stability in the ligaments (bands of tissue that connect bones), resulting in excessive strain on the joints, which can cause arthritis. A high arch is rigid and lacks mobility, causing a jamming of joints that creates an increased risk of arthritis.

Symptoms
People with osteoarthritis in the foot or ankle experience, in varying degrees, one or more of the following:

• Pain and stiffness in the joint
• Swelling in or near the joint
• Difficulty walking or bending the joint

Some patients with osteoarthritis also develop a bone spur (a bony protrusion) at the affected joint. Shoe pressure may cause pain at the site of a bone spur, and in some cases blisters or calluses may form over its surface. Bone spurs can also limit the movement of the joint.

Diagnosis
In diagnosing osteoarthritis, the foot and ankle surgeon will examine the foot thoroughly, looking for swelling in the joint, limited mobility, and pain with movement. In some cases, deformity and/or enlargement (spur) of the joint may be noted. X-rays may be ordered to evaluate the extent of the disease.

Non-surgical Treatment
To help relieve symptoms, the surgeon may begin treating osteoarthritis with one or more of the following non-surgical approaches:

• Oral medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, are often helpful in reducing the inflammation and pain. Occasionally a prescription for a steroid medication is needed to adequately reduce symptoms.
• Orthotic devices. Custom orthotic devices (shoe inserts) are often prescribed to provide support to improve the foot’s mechanics or cushioning to help minimize pain.
• Bracing. Bracing, which restricts motion and supports the joint, can reduce pain during walking and help prevent further deformity.
• Immobilization. Protecting the foot from movement by wearing a cast or removable cast-boot may be necessary to allow the inflammation to resolve.
• Steroid injections. In some cases, steroid injections are applied to the affected joint to deliver anti-inflammatory medication.
• Physical therapy. Exercises to strengthen the muscles, especially when the osteoarthritis occurs in the ankle, may give the patient greater stability and help avoid injury that might worsen the condition.

When Is Surgery Needed?
When osteoarthritis has progressed substantially or failed to improve with non-surgical treatment, surgery may be recommended. In advanced cases, surgery may be the only option. The goal of surgery is to decrease pain and improve function. The foot and ankle surgeon will consider a number of factors when selecting the procedure best suited to the patient’s condition and lifestyle.