Are Acellular Dermal Matrices Effective For Grade 0 Ulcers And Fat Pad Augmentation?
Fat pad augmentation or the use of grafting in the ball of the foot and the heel has gained popularity over the past decade. The goal is simply to add cushioning or padding to areas that demonstrate a loss or displacement of natural fat due to an increased peak pressure.
Patients typically present with pain and verbalize the discomfort they experience while walking barefoot or in shoes, flats and high heels. Patients complain they cannot walk barefoot or in sandals without significant pressure on the ball of the foot or the heel, and feel as if they are walking on pebbles. On the other hand, patients who have neuropathy present with a Grade 0 foot lesion and the physician observes the increased mechanical stress.
In the latter presentation, it is our obligation to diagnose and treat this condition, and prevent progression of the Grade 0 ulceration to more severe levels of breakdown. A Grade 0 lesion by the classic Wagner system (see “A Guide To The Wagner Classification For Diabetic Foot Ulcers” below right) is a pre-ulcerative lesion, healed ulceration site or the presence of bony deformity. These patients usually present with calluses, with or without capillary bleeding, or a healed ulceration with dermal scarring.
One can see increased pressure strain in the heel or the ball of the foot in all foot types. In these cases, clinicians will note subcutaneous atrophy or anterior displacement, which one may observe in the cavus foot where the fat that was once positioned under the metatarsal heads now bunches at the plantar digit sulcus. Genetics, aging, autoimmune diseases with collagen breakdown such as rheumatoid arthritis, previous steroid injections and trauma can also cause loss of the adipose layer. The amplified stress leads to superficial and deep skin problems associated with painful calluses, intractable plantar keratomas, skin breakdown with ulcerations, metatarsalgia, sesamoiditis, neuromas, plantar plate tears and certainly pain.
Clinicians may use a number of methods to specifically analyze fat pad loss in a region. Pedography — with either a classic Harris Mat or a more modern floor-based and insole-based technological system — is available to identify peak pressure loads. One may employ ultrasound or MRI to measure the thickness of the fat pad.
There have been significant advances in treatment options over the past decade. Traditionally, clinicians have offered offloading with pads, orthotics and/or changes in shoes to the patient. Surgical options include a lesser metatarsal V osteotomy, a Weil osteotomy or even a metatarsal head excision. Surgeons have also performed autolipotransplantation, a procedure in which the surgeon takes adipose tissue from the posterior calf or other body part, and transplants it to the plantar fat pad.1
Weighing The Pros And Cons Of Injection Therapy
Over the past decade, injection therapy has gained popularity with the use of collagen, silicone and dermal fillers. One may use dermal fillers off-label for fat pad augmentation. When it comes to injection therapy, clinicians may opt for Graftjacket Xpress® (KCI), Sculptra® (Sanofi Aventis), Radiesse® (Merz Aesthetics) or other commonly used aesthetic dermal replacements.