Diabetes Is Common Cause of Joint Disease

Dear Dr. Roach: My brother-in-law has been diagnosed with Charcot Joint disease. It was discovered when he broke a bone in his foot and had a soft cast. He is diabetic. His foot has been out of the cast for months now, but he seems to be in constant pain in his feet and legs. He had special shoes made for his condition. Please give us an understanding of his prognosis. — D.B.

Answer: A Charcot joint is when the joint is progressively damaged. It occurs in people with neuropathy, and diabetes is by far the most common cause of neuropathy causing Charcot joint. In diabetic neuropathy, you’re not able to feel pain properly, and so you can repeatedly damage a joint without knowing it. The prognosis depends on how early the diagnosis is made. If caught early, the process can be stopped with a cast and special shoes. Surgery is sometimes used, depending on the degree of damage. If the condition is caught late, the joint can be permanently deformed and the skin can become ulcerated, putting the person at risk for infection and even amputation. Fortunately, it sounds like your brother-in-law has gotten excellent care.

The persistent pain in the feet and legs is very likely the result of the underlying neuropathy. Diabetic neuropathy often causes pain and numbness, usually of the feet, but sometimes in the hands as well. Good control of the diabetes is essential, and medications can help, especially medicines like amitriptyline (Elavil), pregabalin (Lyrica) or duloxetine (Cymbalta). A lidocaine patch is a local anesthetic that numbs the area, which can be very helpful if the pain is in a smaller area. It often takes some time to find the right medication for a given person, and it also takes time to increase the dosage to an effective level.

Dear Dr. Roach: I had an MRI for knee pain, and my doctor has diagnosed me with a medial meniscus tear. Can you explain that, and tell me the preferred treatment? — D.H.

Answer: The meniscus is a doughnut-shaped piece of cartilage that sits on top of the tibia, the shinbone. There are two menisci — medial (inside) and lateral (outside) — and they help hold the knee in place and act as a shock absorber to stresses in the knee.

In young people (here “young” means below 50 or so), damage to the menisci comes from high-impact forces — landing wrong after jumping, skiing injuries or other traumas. In people over 50, meniscal damage can come just from degeneration of the cartilage without any serious trauma. Menisci are more likely to be damaged if people are overweight or have arthritis.

A meniscus tear usually causes some pain and swelling of the knee. More-severe tears can cause a sensation of “locking,” where the knee won’t straighten out, or “giving,” where the muscle suddenly feels wobbly or buckles. Meniscal tears commonly hurt more on stairs and are a major cause of pain with prolonged sitting, sometimes called the “movie sign” because people can’t sit through a movie without walking a few steps.

Most meniscal tears get better with conservative treatment — anti-inflammatory medicines like ibuprofen and a program of gradual exercise, best supervised by a physical therapist. If six weeks of conservative management isn’t successful, it’s time to consider arthroscopic surgery. I don’t recommend surgery unless symptoms can’t be controlled with medication and exercise is difficult.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or write to P.O. Box 536475, Orlando, FL 32853-6475.