The poskim cited from the Ba'al HaHalachot that he renders it treifah if one rib was uprooted even though the entire vertebra remains intact, and one should be concerned for his words in a case where there is no great loss [Bach and Shach subsection 4]. However, in a case of great loss, one should not be concerned, as this is against the Gemara and all the poskim [ibid.]. And in truth, the matter is puzzling, for the Ba'al HaHalachot himself wrote before this that whether they were broken or uprooted, it must be in the majority. This is the wording of the Ba'al HaHalachot: If the majority of its ribs were broken, it is treifah, etc. And Rabbi Yochanan said, whether they were uprooted or whether they were broken, it must be in the majority of both sides, and the halacha follows Rabbi Yochanan. And the vitality of those that are uprooted, the upper ones, even without a single vertebra, it is treifah. And even though Rav said until a rib is uprooted and the vertebra with it, it is treifah, the halacha follows Rabbah, etc., who said in the name of Shmuel: when one rib is uprooted from its source, even without its vertebra, it is treifah. Thus far his words. And he contradicts himself. And they wrote that he wrote this for practical application to be stringent, and also the Gemara concludes for practical application to be stringent [Bach]. And the matters are puzzling. And in my humble opinion, it seems clear that the Ba'al HaHalachot had another system in this, and he distinguishes between a rib being uprooted and a rib being uprooted from its source. For behold, the rib is inserted at its head into the socket. Therefore, when it is uprooted only until the socket, and the part inserted in the socket remains in the socket, it is kosher until the vertebra is also uprooted. But if a rib was uprooted from its source, meaning it was uprooted entirely from the socket, it is treifah on the grounds that certainly since it was uprooted from the socket, it cannot be avoided that the socket also moved from its place, and it is like the uprooting of a vertebra. And with this, the wording of the Gemara is precise, for previously it said "uprooted" without qualification, meaning similar to "broken," which is only until the socket; but Shmuel said "a rib uprooted from its source," see there. And according to this, it is possible that even in a case of great loss one should not be lenient, even though all the poskim did not explain it so. And it seems to me that Rashi also holds so [see there, for he wrote regarding Shmuel's statement "from its source, even without its socket," thus far his words. And this is what he wrote on page 42b, starting with the words "a rib was uprooted": even though we learned in a Mishnah, etc., but if one rib was uprooted from its source until half its vertebra, etc., it is treifah, thus far his words. And they emended in the margin "with half its vertebra," see there. But it is not so, for his intention is that the rib was uprooted from its source from the vertebra, where it is inserted until half the vertebra, see there and examine carefully].
הפוסקים הביאו משם בה"ג שמטריף בנעקרה צלע אחת אע"פ שכל החוליא קיימת ויש לחוש לדבריו במקום שאין הפ"מ [ב"ח וש"ך סק"ד] אבל בהפ"מ אין לחוש שזהו נגד הש"ס וכל הפוסקים [שם] ובאמת הענין תמוה שהרי הבה"ג עצמו כתב מקודם זה דבין נשתברו בין נעקרו ברובא וז"ל הבה"ג נשתברו רוב צלעותיה טרפה וכו' ור' יוחנן אמר בין נעקרו ובין נשתברו ברוב שני צדדין והלכה כר"י וחיותא דמתעקרין עילאי דידה אפילו בלא חומרתא חדא בעלמא טרפה ואע"ג דקאמר רב עד דמתעקרא צלע וחוליא עמה דהוי טרפה הלכה כרבה וכו' דאמר משמיה דשמואל כי מתעקרא צלעא חדא מעיקרה אפילו בלא חומרתה טרפה עכ"ל וסותר א"ע וכתבו דזה כתב למעשה להחמיר וגם הגמ' מסיק למעשה להחמיר [ב"ח] והדברים תמוהים ולענ"ד נראה ברור דהבה"ג היה לו שיטה אחרת בזה ומחלק בין נעקרה צלע ובין נעקרה צלע מעיקרה דהנה הצלע תחובה בראשה בהאסיתא ולכן כשנעקרה רק עד האסיתא והמקצת התחוב בהאסיתא נשארה בהאסיתא כשר עד שתיעקר גם החוליא אבל נעקרה צלע מעיקרה והיינו שנעקרה לגמרי מהאסיתא טרפה מטעם דבוודאי כיון שנתעקרה מהאסיתא לא ימלט שגם האסיתא נדדה ממקומה והוי כי עקירת חוליא ובזה מדוקדק לשון הש"ס דמקודם אמר נעקרה סתם והיינו דומיא דנשברה שזהו רק עד האסיתא אבל שמואל אמר נעקרא צלע מעיקרא ע"ש ולפ"ז אפשר דגם בהפ"מ אין להקל אף שכל הפוסקים לא פירשו כן ונ"ל דגם רש"י סובר כן [ע"ש שכתב בדשמואל מעיקרה אפילו בלא אסיתה עכ"ל וזהו שכתב בדף מ"ב: ד"ה נעקרה צלע אע"ג דתנן וכו' אבל נעקרה צלע אחת מעיקרו עד חצי חולייתה וכו' טרפה עכ"ל והגיהו בגליון עם חצי חולייתה ע"ש ואינו כן דכוונתו שהצלע נעקרה מעיקרו מהחוליא שהוא תחוב עד חצי החוליא ע"ש ודו"ק]: