1. Cortisone causes knee osteoarthritis.
This is not true. The reason you’re doctor is recommending a cortisone injection is because your knee is arthritic.
2. A cortisone injection into a knee or shoulder joint will make me fat.
This is also not the case. There is a slight systemic affect when you were given a cortisone injection into a knee or other joint. It may raise your appetite for 1 to 2 days after the injection. You need to consume an excess of 3,500 calories over your normal amount of what you eat per day to gain a pound of weight. A potential slight increase in appetite over one to two days will not cause you to gain weight.
3. Cortisone will deteriorate my bones.
Cortisone injections given into a joint will not deteriorate your bones. If you take oral prednisone (which is a pill form of cortisone) for more than three months in a row, the prednisone can cause osteopenia. Osteopenia is a condition when bones lose their strength. However, a cortisone injection into a joint will not cause osteopenia.
4. You can only get three or four cortisone injections in your lifetime.
You can get cortisone injections every three months in a joint. The rate limiting factor is the fact that cortisone stops being effective if given in intervals closer than three months. There is not an absolute number of cortisone injections you can get during your lifetime. Eventually as the arthritis worsens the cortisone becomes less effective.