Out On A Limb
‘One May Reset A Fracture’
The Sages (supra 53b) forbade taking medicine and performing non-emergency medical procedures on Shabbos due to the concern of sechikas sa’me’manim – that one might come to crush herbs for medicine.
Based on this prohibition, the mishnah (on 147a) states that one may not set a broken bone – ein machzirin es ha’shever – or massage a dislocated bone with cold water in an effort to reset it. Shmuel, on our daf, asserts that the halacha does permit one to reset a bone on Shabbos. Rashi (sv. “machzirin es ha’shever”) explains that Shmuel had an alternate reading of the mishnah. In his version, the mishnah permits resetting a bone.
The Ritva argues that Shmuel rules as he does because he knew by tradition that the position of the tanna in our mishnah was a minority view, disputed by most tanna’im. He explains further that delaying the setting of the bone until after Shabbos could result in irreparable damage and possibly loss of the limb. Therefore Shmuel permitted it being reset on Shabbos. Massaging with cold water, however, is not permitted.
Displacement Or Fracture?
The Tur and Mechaber (Orach Chayim 328) indicate that the Gemara’s permission to reset a fracture implies permission to reset a displaced joint as well. The Magen Avraham (sk 51) disagrees and maintains that “machzirin es ha’shever” refers only to a fractured bone, not a dislocated joint. Resetting a dislocated joint is not an emergency as evidenced by the fact that the halacha even prohibits the mere massaging of a displaced joint in an effort to indirectly get it back into its place. Thus, the Magen Avraham rules that only setting a broken bone is permitted; resetting a displaced joint is not.
A Gentile, A Jew, A Physician
The Mishnah Berurah (O.C. 328:145) disputes the Magen Avraham’s ruling and says that many authorities would opt for leniency and allow a gentile to reset a displaced joint. He notes as well the Shulchan Atzei Shittim who disputes the Magen Avraham and allows even a Jew to reset a displaced joint. He also argues that even the Magen Avraham would be lenient if a physician said that the dislocation is severe and possibly dangerous.
No ‘Smoking’ Glue Gun
The Aruch HaShulchan (328:39) explains that the Tur and the Mechaber believe one may reset a displaced joint on Shabbos because the Gemara uses the word “machzirin – reset,” which implies resetting a limb in its socket. If the Gemara meant to only talk about resetting fractures, it would have used the word “debek – join or glue.”