Recognizing that I have never heard the first two terms, but have spent a career in health care, I would speculate that:
A care pathway outlines the various impediments to care, and the generalized progression to mitigate the usual issues that would limit effectiveness to a satisfactory outcome.
Care strategies would examine the interfaces between care modalities and how to direct those components to the stated goal.
The care plan would take into consideration both the pathway and strategies, but personalize them by incorporating patient limitations, attitude and will to achieve an acceptable outcome. Ideally, the plan would define short term objectives and an optimum time line for achieving these objectives. It would include educational, attitudinal, compliance and physical objectives, and reporting on it's progress would include "plan B" strategies to get back on track in cases of noncompliance.