Our family was vacationing in Disney World when the youngest (six years old) got run over by a golf cart (of all things). He broke the middle of his thigh bone in two places. He was hospitalized and operated on. The surgeon put some kind of new FIIN pin to hold the bone in place. Everyone at the clinic was very enthusiastic about it. We never did figure out what was so special about it. Can you tell us?

A new pediatric orthopedic locking nail was developed by a pediatric orthopedic surgeon who practices in the Orlando area. The device or implant is called a flexible interlocking intramedullary nail or FIIN. It is a long pin made of titanium alloy with a little give to it.

This subrigid device is designed to enter the inside of the femur (thigh bone) from the side of the hip. It curves through the entry and into the femoral canal where it is locked in place to support and stabilize the broken bone.

Studies show that the FIIN is a good choice when surgically treating femoral shaft fractures in children. The advantages of this new type of implant is that there is less blood loss during the procedure, shorter recovery time, and faster return to function. There are also fewer complications with this new device compared with other fixation procedures. And it can be removed nine months to a year later.

There are a few disadvantages to the FIIN implant. There is an increased rate of osteomyelitis with the FIIN device. Osteomyelitis (also referred to as heterotropic ossification) is the formation of bone in the soft tissues surrounding bone.

When osteomyelitis develops after the placement of a FIIN for femoral shaft fractures, it may be caused by the way the new nail is inserted into the bone. More study is needed to understand this problem. Children who weigh more than 100 pounds are not as likely to have as good of results as lighter weight children. The reason for this is unknown but will be the topic of another future study.