Internship on resume

Hi,

I was lucky enough to have a stint as a SA in IB during my sophomore year. I was offered to return to the position as a SA the next year. But i had some serious health issues in my junior year and my countries healthcare meant i had to wait months to get treated. As a result my surgery was scheduled in the middle of the summer and i had to take 6 weeks off after the surgery to recover. Because of this i wasn't able to intern anywhere in the summer apart from some work in the finance department of Non-profits. I was wondering how i would communicate this to potential employers specially seeing as i dont think i can land interviews without a junior year internship.