Elbow arthroplasty or implants used to replace the elbow joint have distinct advantages and disadvantages. As you have been told, before receiving an elbow implant to replace the diseased, degenerated joint, the patient must agree to limit lifting to less than 10 pounds for a single item and less than two to five pounds for repetitive loads. Activities and weight-bearing restrictions will also be advised.
The patient who receives a TEA can expect a stable joint with near normal elbow motion. Complications and problems are fairly common though and the patient must be prepared for this possibility. The implants just haven’t held up on long-term studies. Loosening requiring revision (a second surgery) happens more often than anyone would like. Patients often outlive their implants. The bushings wear out, the parts crack and break apart or come loose. Any of these events will require another surgical procedure.
These are the many reasons why the implant should not be overloaded. Your body weight suspended over the artificial joint is one of those activities that may be fine occasionally. But over time, this activity combined with others that stress and overload the joint/implant can undo what you have gained.
It is always a good idea to bring your concerns and questions up to the surgeon before making a decision like this one. You will want to do everything you can to ensure a successful (long-term) outcome. Your quality of life should improve in terms of pain, motion, and function. But sexual function is an important consideration, too and worth at least one discussion to make sure you are clear on any and all restrictions.