10.14 Needle (Foreign Body) in Foot
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agk's Library of Common Simple Emergencies

Presentation
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Although a needle could be embedded under any 
skin surface, most commonly a patient will have 
stepped on one while running or sliding 
barefoot on a carpeted floor. Generally, but 
not invariably, the patient will complain of a 
foreign body sensation with weight bearing. A 
very small puncture wound will be found at the 
point of entry, and, on occasion, a portion of 
the needle will be palpable.

What to do:
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- Tape a partially opened paper clip as a skin 
    marker to the plantar surface of the foot, 
    with the tip of the opened paper clip over 
    the entrance wound. Instruct the patient 
    not to allow anyone to remove the paper 
    clip until after the needle is removed.
- Send the patient for PA and lateral 
    radiographs of the foot with the skin 
    marker in place.
- Evaluate the x rays. If the needle appears to 
    be very deep you may choose to call in a 
    consultant who can remove the needle under 
    fluoroscopy. If the needle is relatively 
    superficial, inform the patient that 
    removing a needle is not as easy as it 
    appears. Let him know that you are going to 
    use a simple technique for locating and 
    removing the needle, but that sometimes the 
    needle is hidden within the tissue of the 
    foot ("like a needle in a haystack"). If 
    you cannot locate the needle within 10-15 
    minutes, because you do not want to further 
    damage his foot, you will call in a 
    consultant or arrange for fluoroscopy.
- Establish a bloodless field by elevating the 
    leg above the level of the heart, tightly 
    wrapping an ACE bandage around the foot and 
    lower leg, and then inflating and clamping 
    off a thigh cuff at approximately 200mmHg. 
    This will become uncomfortable within l0-15 
    minutes and thereby serve as an automatic 
    timer for your procedure.
- Remove the ACE wrap, clean and then paint the 
    area with Betadine solution, and locally 
    infiltrate the appropriate area with plain 
    1% Xylocaine. (It will be somewhat more 
    comfortable if the needle stick is 
    accomplished from the medial or lateral 
    aspect of the foot rather than directly 
    into the plantar surface.)
- The x rays should give you an idea of the 
    location of the needle relative to the 
    paper clip skin marker.
- With the patient lying prone and the plantar 
    surface of his foot facing upward, make an 
    incision that crosses perpendicular to the 
    needle's apparent position at its midpoint 
    or 1/3 of the way toward the most super- 
    ficial end of the needle. Do not cut deep 
    to the plantar fascia. With any deep entry 
    into the foot, use iris scissors with the 
    blades open to advance a few millimeters at 
    at time before closing the scissor blades. 
    Continue repeating this process until the 
    needle prevents closure of the scissors. If 
    you are using a scalpel blade, as you cut 
    across the needle, there will be an audible 
    clicking sound. Spread the incision apart, 
    visualize the needle and grasp it firmly 
    with a hemostat or small Kelly clamp.
- Now, push the needle out in the direction 
    from which it entered. Even the eye or back 
    end of a broken needle is sharp enough to 
    be pushed to the skin surface. If the 
    needle tents up the skin and will not push 
    through, nick the overlying skin surface 
    with a scalpel blade until the needle 
    exits. Grab this end with another clamp, 
    let go with the first clamp, and remove the 
    needle.
- Let the thigh cuff down and suture your 
    incision closed. Apply an appropriate 
    dressing.
- Provide tetanus prophylaxis if indicated.

What not to do:
---------------

- Do not ignore the patient who thinks he 
    stepped on a needle but in whom you can't 
    find a puncture wound. Get an x ray anyway, 
    because the puncture wound is probably 
    hidden.
- Do not give the patient the impression that 
    the removal will be quick and easy.
- Do not make your incision near the tip of the 
    needle or directly over and parallel to the 
    needle. The needle will not be exactly 
    where you think it is, and your incision 
    will miss exposing the needle.
- Do not persist in extensively undermining or 
    extending your incision if you do not 
    locate the needle within 10 minutes of 
    beginning the procedure. This is unlikely 
    to be productive and you may do the patient 
    harm.
- Do not routinely place the patient on 
    prophylactic antibiotics.
- Do not attempt to remove a buried needle by 
    pulling on the attached thread. It usually 
    breaks, and may create a second foreign 
    body to remove.

Discussion:
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Many a young doctor has been found sweating 
away at the foot of an emergency department 
stretcher, unable to locate a needle foreign 
body. The secret for improving your chances of 
success is in realizing that the x ray only 
gives you an approximate location of the needle 
and that your incision must be made in a 
direction and location best suited for locating 
the needle, not removing it.

There are three additional principles to keep 
in mind. First, the roentgenographic position 
of the needle must be correlated with the 
anatomy of the skin surface rather than the 
bony anatomy of the foot. Second is the simple 
geometric principle that the surest way to 
interesct a line (the needle) is to dissect in 
the plane perpendicular to its midpoint. Third, 
the only structures of importance in the 
forefoot or heel that lie plantar to the bones 
are the flexor tendons and they lie close to 
the bones.

When you let the patient know how difficult it 
sometimes is to locate the needle and remove 
it, you place yourself in a win-win situation. 
You look especially good if you find it and you 
still look experienced and well-informed if you 
don't.

If you choose to take the patient to fluoro- 
scopy, you or the radiologist can place a 
hemostat around the needle under direct vision. 
It can then be pushed out using the same 
technique described above.

Linear foreign bodies such as needles can be 
removed from the sole of the foot without 
extensive dissection, complex apparatus or 
repeated roentgenographic studies. Although 
blind dissection is generally not a good 
technique because of the risk of injury, in 
this particular situation, relative safety can 
be provided by gentle dissection with iris 
scissors of insufficient strength to sever 
tendons, and by setting firm limits of time and 
depth of exploration.

References:
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- Gilsdorf JR: A needle in the sole of the 
    foot. *Surg Gyn Obstr* 1986;163:573-574.

Illustration
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img/cse1014.gif

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