The most common site of arthritis in the foot is at the base of the big toe. This joint is called the metatarsophalangeal, or MTP joint. It’s important because it has to bend every time you take a step. If the joint starts to stiffen, walking can become painful and difficult.
In the MTP joint, as in any joint, the ends of the bones are covered by a smooth articular cartilage. If wear-and-tear or injury damage the articular cartilage, the raw bone ends can rub together. A bone spur, or overgrowth, may develop on the top of the bone. This overgrowth can prevent the toe from bending as much as it needs to when you walk. The result is a stiff big toe, or hallux rigidus.
Hallux rigidus usually develops in adults between the ages of 30 and 60 years. No one knows why it appears in some people and not others. It may result from an injury to the toe that damages the articular cartilage or from differences in foot anatomy that increase stress on the joint.
- Pain in the joint when you are active, especially as you push-off on the toes when you walk
- Swelling around the joint
- A bump, like a bunion or callus, that develops on the top of the foot
- Stiffness in the great toe and an inability to bend it up or down
If you find it difficult to bend your toe up and down or find that you are walking on the outside of your foot because of pain in the toe, see your doctor right away. Hallux rigidus is easier to treat when the condition is caught early. If you wait until you see a bony bump on the top of your foot, the bone spurs will have already developed and the condition will be more difficult to treat.
Your physician will examine your foot and look for evidence of bone spurs. He or she may move the toe around to see how much motion is possible without pain. X-rays will show the location and size of any bone spurs, as well as the degree of degeneration in the joint space and cartilage.