Harnessing The Potential Of The Instep Plantar Fasciotomy

Day in and day out, there is one thing we can count on when we go to the office: we will be treating a patient with plantar fasciitis. Some days it seems like I treat plantar fasciitis all day long.

We all tell our patients that only five out of 100 patients with plantar fasciitis go on to surgery. To that end, I do not think any of us do more than five to 10 surgical cases a year for plantar fasciitis since we get people better with office based care.

I guess because the surgery for plantar fasciitis involves cutting the fascia, nobody really talks about various techniques. Extracorporeal shockwave therapy has fallen out of favor and other than using platelet rich plasma and/or radiofrequency Coblation (Topaz, Arthrocare), nothing is really new. Certainly these new techniques will need to pass the test of time like the plantar fasciotomy. Only time will tell if we are still considering those techniques in five to 10 years.

Unlike other surgeries that have literally dozens of approaches and techniques, plantar fascia surgery is one-dimensional. We can banter all day long about what to do with the adult acquired flatfoot. When it comes to plantar fascia surgery though, the answer is to cut the medial one-third band of the plantar fascia. That is the end of the story.

So what surgical technique do you use for plantar fasciitis? Let us assume for the sake of discussion that you have ruled out any nerve entrapment of the first branch of the lateral plantar nerve (that is a blog for another day). We are discussing straightforward plantar fasciitis.

I was talking to one of my residents the other day and asked him what surgical techniques his attendings are doing for plantar fasciitis. I was surprised at what he told me. A vast majority of his attendings make a small incision on the medial heel and use a Mayo scissor to cut the fascia. Many are doing endoscopic plantar fasciotomies and some are doing traditional DuVries incisions and removing the spur as well as performing a fasciotomy.

Step-By-Step Pointers On Surgical Technique

I want to share with you what I do. Obviously if you are happy with you are doing and getting good results, then there is no reason to change.

I do an instep plantar fasciotomy. It is technically very simple. You can see the fascia and put your finger on it. You know exactly how much you are cutting and are not using the “feel” method. There are no major neurovascular structures in the area of the surgical site. The scar heals well and becomes invisible with time. Moreover, there are no expensive instruments that are necessary to perform the surgery. Even though you can do the surgery in the office if you desire, I do not.

In regard to the procedure, ensure supine positioning of the patient on the OR table. The patient may have intravenous sedation or general anesthesia. Scrub, prep and drape the foot in the usual sterile fashion.

I will evaluate skin lines to help determine where to place the incision. Pushing the toes toward the heel exaggerates the transverse skin lines (Langer’s lines). I will pick one of the skin creases, which is just anterior (distal) to the fat pad of the heel. You should avoid a distal incision in the arch for a couple of reasons. First, you are in danger of injuring the medial plantar nerve. Second, you increase the chances of developing painful fibrotic nodules under the skin incision (fibromas). The wound heals better when there is a healthy layer of fat underlying the skin.

The skin incision is about 2 cm in length in a transverse to oblique orientation following the skin crease. The most difficult part of the surgery is dissecting through the fatty tissue, which is robust in this area. The easiest way to do this is to place a 2 x 3 tooth Weitlander to retract the skin and use a Freer elevator to move the fat around. I will move the Freer elevator up and down (distal to proximal) until the fat liquefies a little and breaks down. Now you can reposition the Weitlander retractor to grab the fat, permitting you to visualize the plantar fascia. Proceed to use a Senn retractor to retract the fat on the medial and lateral sides of the wound. At this point, there should be an unobstructed view of the plantar fascia.

Proceed to perform the plantar fasciotomy. I will use a #15 blade to incise the fascia, taking care not to cut too deep in order to avoid violating the underlying muscle. Dorsiflexing the great toe stretches the fascia and you can appreciate what has been cut. At this point, I will put my finger in the wound and feel medially for any residual fascia fibers that may be intact. I feel this area is much more critical to release than the lateral most fibers. Over the years, I have come to appreciate that less is more as far as how much of the fascia to cut. There is nothing worse than lateral column pain following a fasciotomy. As you know, that is very difficult to treat.

Once the fasciotomy is complete, perform copious lavage and close the wound with three horizontal mattress sutures using 4-0 nylon. Do not use absorbable sutures in the fatty layer as this will increase the likelihood of developing more scarring and potential fibromas. Bandage the foot with gauze and apply a posterior splint or fracture boot.

What The Post-Op Period Entails

The most critical aspect of the surgery is the postoperative course. Regardless of what type of plantar fasciotomy you perform, if you do not splint the foot at a right angle to the leg for three weeks, then there is a great likelihood of the fascia healing in its original contracted position, leading to failure.

With that said, I will have patients be non-weightbearing for three weeks. After the first week, one can remove the sutures and allow the patient to take the fracture boot off to shower and to do some range of motion exercise. All other times, including sleeping, the foot should remain splinted in the fracture boot.

After three weeks of non-weightbearing, full weightbearing in the fracture boot commences. After three weeks of walking in the fracture boot, the patient can return to regular shoes.

I co-authored a paper on a retrospective review of the instep plantar fasciotomy a number of years ago and the findings were overwhelmingly successful in the long-term follow-up of the surgery.1

Reference

1. Fishco WD, Goecker RM, Schwartz RI. The instep plantar fasciotomy for chronic plantar fasciitis. A retrospective review. J Am Podiatr Med Assoc. 2000; 90(2):66-69.