Keeping Surgery Simple: Why K-Wires Are Underrated
In some of my earlier blogs, I wrote about how I like to keep things simple in daily practice. This concept also applies to surgery.
Let’s face it: we are always looking for better ways of doing things in surgery. That is what separates a surgeon from a technician. Maybe you want to tweak the way you make your bone cut or try different fixation techniques. After all, we are always striving for perfection every time we walk into the operating room.
We are influenced by medical literature, continuing medical education seminars, colleagues and vendors to do things differently. Maybe it is a different surgical technique or maybe different types of surgical implants.
Don’t misunderstand me. I do appreciate the engineering involved in new implants that can ultimately provide “better fixation.” However, sometimes I think we get caught up in the hype of “metal mania.” For certain applications, such as medial column fusions in a Charcot foot, high-tech implants such as locking plates may be preferable.
When it comes to forefoot surgery, such as bunionectomy, hammertoe repair and tailor’s bunionectomy, I have found the simple Kirschner wire (K-wire) to be as good as any other type of implant. For a standard Austin bunionectomy and tailor’s bunionectomy, the lock pin technique is fast, simple and cost-effective. If the implant needs to be removed due to skin irritation, one can easily do that in the office. For hammertoes, one can use a Kirchner wire in an intramedullary fashion. The K-wire can do the same thing as the Smart Toe (MMI) or Stay Fuse (Tornier) toe implants for a fraction of the cost or time. In addition, crossing K-wires for arthrodesis of the great toe joint or interphalangeal joint work well especially in the older patient.
The technique of a lock pin application is simple. For the Austin bunionectomy, for example, insert a 0.062 K-wire from dorsal to plantar and proximal to distal into the plantar wing of the osteotomy. Next, I use an offset rasp to protect the dorsal cortex of the bone by resting the rasp distal to the K-wire on the bone. Then bend the K-wire forward towards the toe. The bend should be about 60 degrees. Cut the K-wire, leaving about 7 to 8 mm from the bend. Use needle nose pliers to twist the wire clockwise to rest the pin flush on the dorsal metatarsal neck. Now the cut tip of the wire is pointing proximally. For the tailor’s bunion or lesser metatarsal neck surgery, perform the same technique, substituting a 0.045 K-wire.
The intramedullary pin fixation technique is also quite simple. After removing the cartilage from the base of the middle phalanx and head of the proximal phalanx, use a 0.054 K-wire to make a pilot hole in the middle phalanx and the proximal phalanx. Cut off the tip of the wire to make a blunt end and place the blunt end in the proximal phalanx, making sure not to penetrate the subchondral bone. Cut the wire, leaving 5 to 6 mm of wire extending the proximal phalanx. Apply tension to the tip of the toe, elongating and stretching the toe to allow the wire to be seated in the pilot hole of the middle phalanx. If you like, you can even put a little bend on the toe to make the toe look more natural. One K-wire can fixate all three central toes.
Certainly one technique cannot be applied to all situations. However, I have found the K-wire to be very effective and reproducible in various fixation techniques in the foot. Remember, just because something is newer, does not mean it is better. If all else fails, K-wires can really get you out of trouble when the screw does not bite or is stripped out. Doing it “old school” doesn’t mean that you are “old” or not “schooled” to use other, more advanced fixation techniques.