Aspirin also inhibits blood clotting, which for some can be good and for others can be quite harmful. Aspirin is a double edged sword, having both positive and negative potentials and really should not be taken without supervision. Mother was taking large amounts of aspirin for relief from her arthritis and the doctors prescribed even larger dosages for her pain after the cancer was discovered. It is obvious now that aspirin played an important part in mother's death. Pin-pointing the cause of the arthritis is more difficult than establishing the link between aspirin and interferon.
Arthritis is defined as an inflammation of a joint.
So technically a bruise could inflame a joint and be termed arthritis. Loss of the joint's natural lubrication will allow 'the bones to rub together and cause inflammation also. Poor nutrition inhibits new cell production and calcium utilization and this too will cause the arthritic condition. So far all this is common knowledge in the medical world. In particular the milk's sugar lactose.