मज्जा-अन्तर्गत-नखः दीर्घ-अस्थि-भङ्गानाम्, यथा फीमरस्य (ऊरु-अस्थि), टिबिया(शिन-अस्थि) च भङ्गस्य चिकित्सायै शल्यक्रियाद्वारा प्रत्यारोपितः भवति । lt's a long, metal rod that isinserted into the hollow center of the bone(medullary canal), providing internalsupport and stability to the brokenbone.often used in cases of compleXfractures or when external fixation is notsuitable.They can help healingand reduce the risk of complications, suchas nonunion or malunion.