IM rods are inserted into the bone marrow canal in the center of the long bones of the extremities.
They may be used in thefemur(thigh bone) ortibia(shin bone), for example.
They are also called intramedullary nails.

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Because of this, patients are able to use the extremity more quickly.
Otherwise, the IM rod is designed to stay inside your bone forever.
Screws are used to hold it in position at each end.
Shinbone fractures are also commonly treated with intramedullary nailing.
Screws are placed on both ends to keep it in position during healing.
The rod ensures that the position will be maintained better than just using a cast or external fixation.
This may be done for bones that are at risk for fracture.
Telescoping rods may be used for growing children.
They lengthen as the bone grows.
Springer Science & Business Media; 2002.
Osteogenesis Imperfecta Foundation.Rodding Surgery.