You do not mention how old your girl is or if she recently had a tick issue. When Basenjis are in advanced age they can be afflicted by arthritis. Lyme disease can damage joints. My females at an advanced age, around 11 - 13, have had arthritis. They would hop down from the couch and injure either a joint in the paw or leg or shoulder. I noticed because they would either : stumble on landing then limp; or they would come back to the sofa and could not hop back up. They could not pressure or weight on a joint in preparing to jump up. I would watch them hesitate and stop. Arthritis is unfortunate and difficult to treat. I would intervene and not let them hop up or down until the tenderness went away (up to a week). I would always use a new voice command of 'wait' then lift them up or set them down on sofa or bed. 'Wait' was never used at any other time. A series of steps could help if you can get them to use them. They would get better over time and the tenderness of the condition would subside, for months at a time, until they hopped down and re-injured themselves. It is hard to get a Basenji to take it easy and you can't be with them 24 hours a day. However, you may be able to change arrangements such that there is nothing to hop up to or down from when you are not with them. Eventually my girl would come up to me and wait for me to lift her up to the couch. And of course when she did feel better she would not wait at all and just proceed to hop like she always had before.