hammers, screws and Intramedullary nails

If you study orthopaedics, you’ll know for sure that IM femoral nailthe femur is the longest, heaviest and strongest bone in the human body. One day, by chance, it happens that you see a bar like the one in the picture on the right. Well, maybe you’ll also notice two things: it is as long as your femur bone and it has more or less the same curvature. With a bit of fantasy and science fiction mood, you could even get to figure out a strange surgery where such long bars are plugged into the bones of some patients in order to strengthen their skeleton and create an army of solid soldiers.

There’s no need to invent anything like that, since we are talking about a surgery that already exists (but not for military purposes). Intramedullary nailing consists in forcing a metal nail (or rod) into the medullary cavity of a bone. Normally, IntraMedullary (IM) nails are employed to treat fractures of long bones of the body. Nowadays, this surgery is regarded as the standard of treatment for both femoral and tibial shaft fractures.

Let’s focus on an IM femoral nail. What about its surgery?

First, the surgeon makes use of a Reamer. Wikipedia defines it as a “metalworking tool used to create an accurate sized hole“.  The medical version of this device is actually employed to hollow out the center of the medullary canal of the femur, by accessing it from the top (next to the pelvis bone). This doesn’t affect too much the bone solidity and is necessary when the medullary cavity is not continuous (for example, in the case of broken leg injuries).

Once the femur has been properly drilled, an intramedullary nail is tapped into place. This means that a hammer is used to push the rod down into the hollow medullary cavity. In a sense, this action recreates a well-defined medullary cavity in the case of displaced or unstable fractures. Moreover, it obviously provides stabilization for the healing bone (that starts growing again in a proper “shape”).

Finally, screws are usually placed in the head of the femur to secure the nail and prevent its collapse or rotation. During the progressive return to activity, the leg of the patient will take benefit from the fact that the loads will be shared by both the healing bone and its solid metal core. This leads also to a faster rehabilitation period (which requires a first non-weight bearing stage followed by specific exercise programmes).

hammer IM nail

After the implantation, the intramedullary nail is usually left inside the bone forever. In some cases, the patient may develop some long-term complications that cause pain and general ache at the insertion site. In such cases, a second surgery might be necessary to remove the IM nail from the recovered bone. Wikipedia gives us some interesting data about long-term complications of IM nailing for the femur, that “may include persistent or permanent knee pain (present in 73.2% of patients), atrophy of the calf muscle (27.3%), atrophy of the quadriceps (27.3%), and arthritis (35.4%)“.

The following image shows the femoral fracture (A) and the IM nail inserted all along the bone (B), the relatively small scar on the patient’s leg (C) and the recovered bone (D, E).

IM nailing steps

sources: Wiki, Journal of Orthopaedic Science and About.com

11 thoughts on “hammers, screws and Intramedullary nails

  1. Pingback: let’s take stock of … the lower limb ! | andreacollo

  2. Right here is the perfect site for anyone who hopes
    to find out about this topic. You realize a whole lot its almost tough to argue with you (not that I personally will
    need to…HaHa). You definitely put a fresh spin on a topic that has been discussed for many years.

    Excellent stuff, just wonderful!

  3. I am Tatjana Andan from Serbia. My son Zdravko had a skiing accident in France (he broke his femur 11 January) and you have it operated on. His recovery is running great.
    I would have one question for you.
    My son is 15 years old and intensively growing.
    What is your opinion on the equal growth both femur?
    Maybe for you my question is strange, but I have afraid that screws prevent the growth of leg.

    • Hi Tatjana, thank you for your comment.
      Your question is not trivial at all, I am not a MD so, unfortunately, I cannot really support my reply but… I would say that, in that case, nails are properly removed and replaced with longer ones, in order not to affect growth. This other webpage introduces an example of cannulated nails (for tibia), maybe they could be a good solution… even if, obviously, they lead to other kinds of problems (such as excessive bone ingrowth).

  4. Andrea, I’m very sorry that I have not thanked you for your response.
    Serbian surgeon assured me that my son IM nail can not interfere in terms of growth.
    Also the doctor’s opinion is that there is no need to IM nail removed.
    I read a lot about it. What is your opinion? Whose arguments are stronger?
    Best regards, Tanja

  5. Hi Tanja, thank you again for trusting my opinion, even if I’m not a surgeon 🙂
    You see, every surgeon has their own “philosophy”: drawing upon their own experience, they operate by adopting one approach or another.
    For sure, the implant (ie: tipe of IM nail) that the surgeon chose for your son is the one he considers the most reliable choice possible.
    Any surgical choice and procedure has undoubtedly been done and followed in the interest of your son, considering his growth and healing processes 🙂

    • Thanks Andrea for your opinion. I have to look everything.
      Surgeon is of that opinion but it is not definitely.
      I think that the IM nail done the job ie. no problems for him but there is not benefit. I don`t see why that wears in leg 200-300 gr some kind of metal whole life.
      Sorry but I think as a mother 🙂

      • Don’t worry 🙂
        I am not an expert, but for sure the surgeon chose the best solution possible.
        In some cases, “wearing” a piece of metal may let one live their own life practically without any limitation!
        I think that it could be considered a very good price to pay when worse scenarios are expected (such as, for example, being constrained on a wheelchair or undergoing amputation).

  6. From personal experience, I would wait and see if there is any irritation to the bursa from the nail. I am suffering from trochanteric bursitis from the head of the nail. I am 2 years post surgery and have gone through injections and PT to try to relieve symptoms, Many have no problems but some do! Now I am having removal surgery to try to get some relief.

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