The goal of this clinical trial is to test whether there is any effect on rotator cuff healing by making microfracture at the lateral side of the footprint. The main question it aims to answer are: * \[whether the lateralized microfracture could decrease the retear rate after arthroscopy rotator cuff repair.\] * \[whether the lateralized microfracture could improve the functional recovery after arthroscopy rotator cuff repair.\] Participants with medium to larger size rotator cuff tears will be randomly assigned to the study group treated with lateralized microfracture immediately after arthroscopy rotator cuff repair or the control group treated with conventional arthroscopy rotator cuff repair without microfracture.