It’s not advised without checking with your doctor and therapist first. Rehab programs for shoulder injuries must progress at a rate that recovering tissues can handle. Usually, this is from low- to high-demand exercises.
Some muscles are more active than others in different positions. The therapist starts patients out in positions that are easy on the healing tissue. For example, being on hands and knees puts the least stress on shoulder muscles. Push-ups against the floor put the most stress on the shoulder. There’s a wide range of positions and exercises in between.
Early rehab exercises must put a low demand on the recovering muscles. Higher loads should be put off until the tissues and muscles can accept greater demands. The load on the joint and muscles may be greater than you think. The therapist knows how to balance how much load the shoulder can accept without dislocating or causing reinjury to the muscles.