DEAR DR. ROACH: While chasing my cat, I dove to the ground and both my knees took a beating. They were bruised but felt fine. A few days after this, my left knee started to bother me. I put on a brace to see if that would help (as it usually does), but it didn’t. I went to my chiropractor a few days later and had an adjustment and deep tissue massage. The next day, I was walking my dog and had to stop, as I couldn’t move my knee. About 13 years ago, I had a torn meniscus in the same knee, and it healed without surgery with the assistance of my chiropractor, massage therapist and acupuncture.

I called my doctor’s office, and he was out of town. His nurse suggested that I go to an urgent care facility to have an X-ray of my knee, which I did. The doctor said that nothing was broken but that I should follow up with an MRI. I saw my doctor a few days later and brought my X-ray, etc. He said I don’t need an MRI. I am not looking for knee surgery, but wouldn’t an MRI indicate if it is a torn meniscus, pulled ligament, osteoarthritis, etc., so I could get the proper treatment? What would that be? — R.Z.

ANSWER: The menisci are ring-shaped cartilage structures that sit on top of the tibia and provide stability and shock absorption to the knee. Given the mechanism of injury and your prior history, a meniscal tear is a very likely possibility. Symptoms that support a tear in the meniscus would include a locking of the knee or a giving sensation while walking, often associated with pain.

A careful physical exam can usually make the diagnosis of a meniscal tear. A suspected meniscal tear does not usually require an MRI, as most will heal with conservative management. (I refer nearly all to physical therapy rather than the treatments you used, but I won’t argue with your success.) I reserve the MRI for people in whom surgery would be contemplated. Since surgery is no better than placebo for many people with a torn meniscus, I am particularly careful to refer only people who have not gotten better with a good trial of conservative management.

DEAR DR. ROACH: I have an affected nerve in my back causing long-term, persistent pain. Years ago, I damaged a sacroiliac nerve in a fall. This was treated by steroid injection. Could this individual nerve also be injected with a steroid? — J.D.

ANSWER: Injection of local anesthetics and steroids are done for several different types of back pain syndromes. However, the nerves themselves are not injected with steroids: It’s the area around a nerve that is injected. That area may be inflamed, and the shot is given with the hope of reducing inflammation and thus reducing compression on the nerve and therefore pain. It does not always work, and when it does, the pain relief usually lasts a matter of months. The injections can be repeated if helpful; however, injecting steroids has its own risk of complications. Serious complications are rare, but infection and bleeding are possible. Injection for back pain is done most often by pain management specialists when appropriate.

DEAR DR. ROACH: I am an 87-year-old man in good health. Recently my physician discovered that I was having atrial fibrillation. I had no symptoms. My pulse was 80. He placed me on Eliquis twice daily, which I am taking. I feel fine, but I dislike taking anticoagulants and prefer other treatment for my condition. Is there other treatment you recommend? — H.A.S.

ANSWER: Atrial fibrillation is a common rhythm disturbance. Treatment is designed to reduce symptoms, prevent heart damage from too fast a heart rate, and prevent a stroke from a blood clot. Since you have had no symptoms and your heart rate is normal, you need no therapy to control your heart rate. However, you are at increased risk for stroke just because you are over 75 years old, and oral anticoagulation from apixaban (Eliquis) or another agent is strongly recommended. Without treatment, you have about a 4% risk of stroke per year. With treatment, your risk is only about 1%. It’s much riskier NOT to take the medicine.

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