Just be careful to find positions that do not aggravate the back problems. Joint replacement surgery, especially for hips and knees, present very specific problems when it comes to sexual activity. You need to address this with your physician before you leave the hospital. Ask if you should abstain from sexual activity or just avoid certain positions for a certain period of time. Sexual satisfaction can be achieved in many ways.
Arthritis can make intercourse difficult.
Stimulating your partner manually, orally, or with a vibrator in a caring, romantic way, can be satisfying. On the other hand, despite your feelings of affection, there may be times when either you or your partner simply doesn't feel very passionate. Then you or your partner can certainly stimulate the other person and satisfy their sexual needs. Masturbation is also a healthy way of achieving the same goal. It can also reassure you of your own normal sexuality.