A 22-year-old male presents to clinic with complaints of right shoulder pain ongoing for about 3 weeks. He states he has been going to the gym more frequently to become more fit. He says the pain is intermittent and is worse with deep breaths. He describes the pain as sharp and rates the pain a 5/10 at worst. No alleviating nor aggravating factors are identified on further questioning. Osteopathic structural examination reveals decreased restriction of movement on exhalation of ribs 7-10 on the right. Which of the following muscle groups should osteopathic treatment be focused towards?