<s>[INST] I was doing leg press in the gym today. When I brought my knees to my chest I heard a "pop" just below my left ribs . Now several hours later I have some pain when I do a "crunch" or arch my lower back . What could this injury be ? What treatment can be applied ? [/INST] thanks for your questionpossible reasons can be a -rib fracture or a muscle injuryin my patients with the similar compalints i prefer requesting for a chest xray to rule out the above mentioned causes and prescribe them some analgesics and enzymes to quicken the healingyou need to consult a pulmonologist and disscuss the above modalitiesthanksfeel free to ask more questionsmay god bless you with good health </s>