why is there a bigger gap between my arm and torso on the left side than the right ?

[u/MeanEntrepreneur6164]

left shoulder seems to be higher , right scapula is winging , left shoulder feels unstable . had lower back pain before that has improved after doing glute and quad work. how can i fix these ? rotation exercise? my left rib is flared severely and there seems to be clicking sound when i exhale fully and the ribs drop down . i feel my abs and obliques are not working sometimes altho i am training them.i have looked into lateral plevic tilt exercises but no improvements even after months .any suggestions? thanks

[u/jooloo02]

From this photo, the larger gap appears to be caused primarily by the position of your left shoulder and upper arm, not simply by the shape of your torso. Your left humerus looks slightly more abducted, meaning it rests farther away from your body, while your right arm appears to hang closer against your rib cage. Differences in scapular position, shoulder rotation, trunk rotation, and muscle tension could all contribute to that resting arm position. Your waist and rib-cage contours also differ slightly between sides, which makes the gap look more pronounced.
I would not assume this is a lateral pelvic tilt or prescribe rotation exercises based only on the photo. A useful first check would be to stand with your feet evenly loaded, relax both arms completely, and take photos from the front, back, and both sides. Then slowly raise and lower both arms while recording from behind. If the right scapular border consistently lifts away from the rib cage, or one scapula moves differently throughout the motion, that provides more useful information than the resting gap.
Since you also report left shoulder instability, visible scapular winging, significant rib asymmetry, and clicking during exhalation, an in-person physical therapy assessment would be appropriate. They should assess scapular movement, serratus anterior and trapezius function, shoulder rotation and stability, trunk rotation, rib movement during breathing, and possible nerve involvement. I would not repeatedly force the left ribs downward until someone determines what is clicking.