Pertinent Insights On The Potential Of Fat Transfer To The Dorsum Of The Foot

Fat transfer to the dorsum of the foot has been gaining more and more interest in the podiatry field as we see the differences that fillers have made for patients. We have been able to change the lives of patients who previously could not walk pain-free and were not good candidates for surgery. In plastic surgery, fat transfer is a widely accepted procedure that has shown profound results in body contouring. By harvesting fat and placing it into high pressure areas of the foot, we are able to see even longer-term results in my experience than with injections alone.

In previous DPM Blogs, I had mentioned autolipotransplantation to the plantar aspect of the foot for high plantar pressures but in this blog, I will discuss a new indication of transferring fat into the dorsal aspect of the foot.¹ Plastic surgeons and dermatologists have been using fillers such as Radiesse (Merz Aesthetics) and Juvederm (Allergan) in the hands due to thinning of the skin and atrophy of subcutaneous tissue. The same condition occurs on the dorsum of the foot. One example is extensor substitution in the cavus foot as well as atrophy of the subcutaneous tissue in the dorsum of the foot.

With the fat typically being harvested from the buttocks or the abdomen, it is best to work with the plastic surgeon, who can perform liposuction. The treating physician performs the minimally invasive procedure with the patient having local or general anesthesia. Recovery for the liposuction procedure is minimal with the patient wearing compression garments and resuming activity after a couple of weeks. The amount of fat harvested is much greater than what will be necessary. If you have an appropriate method to freeze and store any remaining fat, I recommend it as one can inject the foot while the patient is in the office at a later date.

After harvesting the fat and collecting it in a canister, transfer the fat to 10-cc syringes or tubes. The fat can settle in syringes or tubes on your back table where the fat rises to the top, and the water and blood drain to the bottom. Another option is separating the fat under centrifuge at roughly 300 rpm. Discard the water portion of the resulting liquid. The fat remains in the syringe and one can mix this with bacitracin as well as amnion membrane for injection therapy.

Mixing the fat with amnion membrane does stimulate more collagen production and better acceptance of the graft, but there is no scientific evidence to support this. Once you have prepared the fat, you are ready to inject it. One can do this with either a needle larger than 18 gauge or a fine-tip cannula. Typically, the fat does clog an 18-gauge needle so it is advisable to use a larger bore.

On the dorsal aspect of the web space at the first metatarsophalangeal joint, you can access most of the foot. Insert the cannula dorsally in the subcutaneous tissue and inject the foot as you move the cannula. I like to perform this in a fan-like motion. You can move the cannula across all dorsal aspects of the foot, accessing all the web spaces as well as the dorsal sulcus.

One can easily contour the fat. You want to smooth it out so there are no bumps or unevenness. Take care not to enter the tendon sheath or the joints. With this blunt tip, you want to avoid damage to any neurovascular structures. The goal is to place the fat between the tendons in the dorsal web spaces to fill out the subcutaneous tissue. Place a Steri-Strip at the area of insertion of the cannula and place a dry sterile dressing on the foot.

Post-procedure, I recommend pain management with Tylenol or a low-dose narcotic but try to avoid anti-inflammatory medication. The patient can ambulate in stiff-soled postoperative shoes and perform minimal activity for three weeks. Roughly 10 to 15 percent of the fat will resorb over time and more atrophy can occur due to factors including activity level, nutrition status, etc.

Within six months of the original procedure, if there is remaining fat, one can thaw and inject it in the foot in the office.

Reference

1. Schoenhaus Gold J. Treating fat pad atrophy. Podiatry Today DPM Blog. Available at https://www.podiatrytoday.com/blogged/treating-fat-pad-atrophy . Published April 3, 2017.