A 70-year-old male presents to clinic with complaints of chronic low back pain. He states that he is having difficulty completing his activities of daily living due to the pain. He describes the pain as dull and rates it a 4/10 at worst. He has tried over-the-counter medications without significant relief of his symptoms. Osteopathic structural examination reveals a sacral sulcus that is deeper on the left as well as a positive sphinx test. Which of the following somatic dysfunctions does this patient exhibit?