Most using nandrolone for joint issues/bone pain are using low doses indefinitely or short-term off and on.
Very rare anyone does a few cycles and all of a sudden the joint issues/bone pain is permanently gone.
Many on trt let alone therapeutic doses of nandrolone still continue to beat up their joints/tendons/ligaments from weight-training.
No matter how smart you train (diet/rest/recovery, form/technique, load) wear, and tear is still going to happen.
Think of how many older iron-heads have beat up shoulders, elbows, knees, backs.