Most people have a completely incorrect angle between keyboard, wrist and arm. Working from couch typically increases this angle even further. You should see a

Most people have a completely incorrect angle between keyboard, wrist and arm. Working from couch typically increases this angle even further. You should see a significant improvement if you reduce that angle. Basically, you don't want your hand to be going "up" at the wrist. Inasmuch as possible strive to have your hand flat through the wrist, or even fall down slightly. If you don't have room for a mouse, get a trackball. They're relatively cheap and not having expensive health issues is worth it. Be inventive in changing up the posture. If you genuinely don't have any other surface (dining room table, kitchen counter etc), switch it up - put laptop on couch and sit on the floor. Sit on couch with laptop on your knees, lie down with laptop on your lap or chest, put the laptop on window sill or fridge or counter or shelf and work standing, etc. NONE of these are ideal, but changing is important.