I am 58 yr old female with a left partial knee replacement . I had the surgery five years and have been doing well. However, around two months ago I injured my knee while caring for my sister s dog. My leg was planted on the ground while the dog tried to dart off and I twisted around with the leash in my hand and felt immediate pain. It felt a little better after icing, but in four weeks I experienced very bad pain. I had an xray and it showed that there was no bone to bone contact in the knee. From the orthopaedic s examination, he suspected a meniscus tear. After an mri , he found that the meniscus was torn in the front, but he also discovered very bad arthritis in the knee. The question is whether the arthritis caused the meniscus tear or if the meniscs tear is now aggravating the arthritis which never bothered me in that knee until my injury. The doctor has great credentials but he wants to try an arthroscopy for the meniscus tear initially. He said I had a 50/50 chance of getting relief and it might buy me time before having to replace this knee. This type of surgery would entail a total knee, versus the partial knee replacement on my other knee. I am on substantial pain meds and don t want to continue this way, but I don t know if it is worth doing the arthroscopy first or just having the total knee done. I would like an answer from an orthopedic surgeon, not an internist.