Can doctors replace elbows like they do hips and knees? If so, could the arms bend both ways?

Yes, doctors can replace elbows, although the procedure is much more complex than replacing hips and knees. The procedure is called elbow arthroplasty or elbow resurfacing but it's more commonly known as a total elbow replacement. Unlike hip and knee replacements which require only one prosthesis for both sides of the joint, an elbow replacement requires two prostheses to be implanted - one in each arm bone.

The new parts are designed to fit together like a puzzle so that they mimic the range of motion of a normal healthy joint. This allows the person’s arms to bend and rotate normally - including being able to flex the elbows up at least 90 degrees or even up to 120 degrees depending on individual circumstances. Recovery post-surgery typically takes several months of physical therapy before full strength is regained in that arm – however if successful, this surgery can dramatically improve quality of life for those suffering from severe arthritis or trauma in their elbows!