In terms of the the setting of "A Worn Path," the structure can be divided into two parts: the journey and the doctor's office. Since Phoenix's name recalls the mythical bird which rises from the ashes, we might consider that Phoenix, being probably around 80 years old, continues to defy the odds and repeats (rises again) this journey to obtain medicine for her grandson. In this respect, the story itself is placed within a larger structure of recurring trips to the doctor's office, each trip like the mythical phoenix repeatedly rising from the ashes. Thus, the repeated journey creates a 'worn path.' Also, the journey itself is meant to symbolize the larger journey of life.
The structure is also thematically framed first by obstacles in nature and then obstacles with society; namely, racism and ageism. This is no mistake as it compares the plight of an old woman living in the rural south with the fact that she is African-American living in a post-Civil War era where racism certainly still existed: another obstacle. The clearest indication of this is the condescending way the hunter talks to her. "I know you old colored people! Wouldn't miss going to town to see Santa Claus!" Phoenix does receive some help along the way but it is coupled with condescension. At the doctor's office, she is helped but as a charity case. The nurse willingly helps but calls her grandson's predicament "an obstinate case." Interestingly, the sequence of this thematic structure of struggle begins with struggling against nature and ends with allusions to social struggles. But in between those natural and social struggles, Phoenix runs into a scarecrow.
She shut her eyes, reached out her hand, and touched a sleeve. She found a coat and inside that an emptiness, cold as ice.
This figure, which she initially calls a ghost, is made from nature (straw, cloth) but is human-like. This is a fitting transition from her naturalistic obstacles to the instances where she is helped but chastised ("cold as ice") by other people.
The fact that she momentarily forgets why she came can be interpreted as an effect of her age, but it also underscores the phoenix theme. Just as the phoenix is burned (erased) to ashes only to rise again, it's as if Phoenix's memory is erased only to reform.
So, the setting structure is the journey itself followed by the doctor's office followed by Phoenix's departure from the doctor's office. The thematic structure, tracing the theme of struggle, goes from nature's obstacles to a (perhaps mystical) interlude with the scarecrow to her encounters with other people. As an allegory for the journey of life, this "worn path" represents all these struggles: natural, spiritual, and social.
It's hard to ignore the religious allusions which put this story within the framework of a religious pilgrimage as well. It is December (Christmastime). The scarecrow is on a cross; this Christlike figure parallels the phoenix, both spiritual beings who are resurrected. The overarching structure, then, is the journey, as nature's path or the path of life, from struggle to resurrection.