Football Dressing for Neuropathic Forefoot Ulcerations
The risk of infection and amputation related to neuropathic ulcerations in the diabetic population drives the desire for timely and optimal healing in these patients. The documented gold standard for healing neuropathic wounds is the total contact cast (TCC).1–10 Studies have consistently demonstrated the effectiveness of the TCC and, most recently, the instant total contact cast (iTCC).1–10 Barriers to physician use of TCCs are mostly concerns related to the time and complexity of application, cost of materials, and complications attributed to the TCC.11
Katz et al1 demonstrated that TCCs and iTCCs have equal efficacy; however, the iTCC is less expensive and easier and quicker to apply. The costs of the TCC and iTCC are $210.67 and $158.47, respectively.1 Half shoes, applied felted foam, and scotch cast have shown healing times inferior to TCCs and iTCCs.12–14 The MABAL shoe study had average healing rates for neuropathic diabetic foot ulcers at about 5 weeks, and although comparable to TCC, all wounds were Wagner Grade 1.15 Birke et al10 evaluated forefoot ulcer healing using a TCC, an accommodative dressing consisting of a modified surgical shoe and felt, a healing shoe, and a walking splint, and average healing times were 47.7, 36.1, 41.4, and 50.5 days, respectively. In at least 81% of the cases, these forefoot ulcers were healed within 12 weeks irrespective of the method used. All patients in this study were given instruction for partial weight-bearing using crutches or walkers.10 Recently, a prototype pressure-relieving dressing was introduced and demonstrated a reduction in pressure by 30% at individual metatarsal heads.16
Wound healing in patients with diabetes is often impaired by the loss of peripheral pressure sensation that permits painless weight-bearing on an ulcerative area leading to a chronic ulcerative process.11 Component causes of lower-extremity ulceration in patients with diabetes include peripheral neuropathy, deformity, and trauma. Peripheral neuropathy is the most common cause.17 Removal of 1 or more of the causal pathways can prevent or delay foot ulcer development.17 In neuropathic ulcerations of the plantar foot, effective offloading will lead to healing with predictable rates and patterns. In most studies, the average healing rates using TCCs range from about 4 weeks to 6 weeks.1–10 Recently, removable cast walkers (RCWs) and iTCCs have demonstrated healing rates of 51.9% and 82.6%, respectively, in 12 weeks.18 Although previous studies have demonstrated effective decreases in plantar pressure with the use of RCWs compared to TCCs, the lack of compliance with RCWs leads to lower healing rates.19–22 Armstrong et al19 demonstrated the problem of compliance when utilizing RCWs for offloading. In this study, patients wore the RCW for a minority of the steps taken during the day, utilizing the RCW only 28% of the time during daily activities.
A number of studies have evaluated the healing time of diabetic foot ulcers when treated properly. Sheehan et al23 defined good clinical care of diabetic foot ulcers as offloading, frequent sharp debridement, and moist wound healing. Sheehan et al23 demonstrated that diabetic foot ulcer wound healing at 12 weeks can be predicted by the percentage change in area during the first 4 weeks of treatment. A wound that fails to decrease in size by 50% by 4 weeks is unlikely to heal in a reasonable time.23 Margolis et al24 also illustrated expected healing times for diabetic foot ulcers by demonstrating the change in area of a wound at 4 weeks predicts healing at 12 to 20 weeks. Wound size, duration, and grade are associated with likelihood of healing at 20 weeks.25 Margolis et al26 stated healing benchmarks for diabetic foot ulcers allow healthcare professionals to provide patients with a realistic assessment of their chances of healing and provide information that can be used in designing clinical trials. These studies have provided benchmarks for expected healing times for neuropathic diabetic foot ulcers. For Wagner grade 1 or 2 diabetic foot ulcerations, the expectation is the wound should be healed in 12 weeks with effective offloading. Moreover, significant healing should be noted within the first 4 weeks of treatment with a 50% reduction in ulcer area.
Rearfoot and forefoot pressures are increased in patients with diabetes and peripheral neuropathy.27 Both forefoot and rearfoot plantar pressure ratios are increased in patients with severe diabetic foot ulcerations.27 The quality and variability of activity may be more likely to lead to ulceration even in patients who are less active.28 Sudden changes in activity and routine loading of plantar tissues may result in tissue injury as compared to absolute value of peak plantar pressures or number of steps with regard to plantar ulcer recurrence.29
A semiquantitative analysis of histopathological features of neuropathic ulcers performed by Piaggesi et al30 demonstrated decreased inflammatory and reactive components and accelerated healing with TCC utilization. This helps confirm the importance of offloading neuropathic ulcerations. Birke et al31 demonstrated no difference in healing time between patients with leprosy and patients with diabetes. Their findings support loss of protective sensation and mechanical stress as the primary etiology for plantar ulceration in both groups.31 Appropriate wound care, debridement, and pressure reductions are the keys to successful treatment of neuropathic foot ulcers.32
The key to a wound dressing and offloading modality is the effectiveness, ease of application, availability of materials, cost, and the likelihood of compliance. The cost and ambulation problems associated with iTCC and TCC use make these options unsuitable for some patients. In an effort to develop alternatives for patients with neuropathic ulcerations where TCCs, iTCCs, and RCWs are not good choices, the authors developed the “football” dressing. In order to evaluate this dressing, the authors compared the healing rates to that of TCCs and iTCCs. Most healthcare professionals can easily apply the football dressing, and the materials are widely available and inexpensive.
This prospective analysis is composed of patients from the Center For Wound Healing in Huntingburg, Ind, and the Wound Care Center in Jasper, Ind. The purpose of the study was to evaluate the effectiveness of the football dressing in healing diabetic forefoot ulcers of primarily neuropathic etiology. The patient population was carefully chosen to limit the role of cofactors, such as arterial insufficiency and altered glycemic control. Standard instruction regarding the importance of offloading, regular sharp debridement, moist wound healing, decreasing wound bacterial load, proper diet, and recognition of subjective symptoms consistent with infection was given to all patients. Patients were told to limit their ambulation to the truly necessary, although no assists (eg, crutches, wheelchair, cane) were employed.
Fifteen subjects were enrolled of which 7 patients required insulin and 8 required oral hypoglycemic medication to control their diabetes. All enrolled subjects were medicated for glycemic control prior to entering the study. No adjustments in glycemic control were made. All patients were deemed to have adequate arterial supply by the presence of 2 palpable pedal pulses. Alternatively, the presence of biphasic or triphasic waveforms on Doppler evaluation of a nonpalpable pedal pulse was also accepted. Sensory neuropathy was confirmed with monofilament screening. In all cases, there was absent sensation to a new 5.07 monofilament stimulus at more than 7/10 pedal sites. All wounds were graded with the University of Texas Health Science Center (UTHSC) wound classification system.33 Included were 1A, 1B, 2A, and 2B wounds. All 1A and 1B wounds were full thickness.
The wounds were subjected to once weekly sharp debridement. Any antibiotic use was employed orally and was deemed appropriate based on clinical signs of infection. The choice of antibiotic was guided by deep cultures post debridement and flushing of the wound. Primary wound dressings were a nonadherent layer followed by a silver-containing dressing and absorbent foam as indicated based on drainage. The football dressing consists of 3 rolls of 4" cast padding, 1 roll of 4" gauze, and 1 roll of 4" self-adherent wrap (Coban™ Self-Adherent Wrap, 3M Healthcare, St. Paul, Minn). The initial layer of cast padding is fan folded and applied in a longitudinal fashion. A second layer is then applied circumferentially about the forefoot. The final layer is applied from the forefoot proximally to the lower leg. A layer of 4" gauze is then applied over the entire dressing and is covered by a layer of self-adherent elastic wrap applied without tension (Figures 1–8). A standard post-operative shoe was dispensed for ambulation on the dressing.
Weekly measurements of wound length, width, and depth were taken post debridement. The wounds were photographed and described on the wound center’s standard wound evaluation form. The weekly change in wound surface area and volume was monitored as well as the total number of weeks to complete epithelization.
Statistical analysis. All descriptive data are presented as mean ± standard deviation. A t test was used to compare results of infected and noninfected wounds. For these analyses, an alpha level of 0.05 was considered statistically significant.
Wounds were graded on initial presentation by the UTHSC wound classification system.33 There were 6 1A, 4 1B, 3 2A, and 2 2B wounds followed. Seven individuals required insulin and 8 did not. All wounds were plantar forefoot wounds of at least 6 weeks duration. The mean surface area of all wounds was 1.68 cm2 ± 2.81 cm2. Mean depth of the wounds was 0.16 cm ± 0.106 cm. Infected wounds had larger mean surface areas as compared to noninfected wounds, 2.71 cm2 and 0.984 cm2, respectively. A t test was applied to infected and noninfected wound healing rates. The single sided probability that the 2 variances are equal (F test) is 0.04798. Infection of the wound was not found to be a statistically significant factor in healing with the football dressing (P = 0.2). Total time to healing of the foot ulcers was 3.80 ± 2.60 weeks (range 1–10 weeks). No patients failed to heal the plantar foot wounds, and no secondary wounds were created with the use of this dressing.
The search for a repeatable, inexpensive, and efficacious dressing that addresses the need for nonremovable offloading of the neuropathic plantar forefoot ulcer is what led the authors to propose this model. Published studies evaluating the TCC consistently report mean healing times of 4 to 6 weeks.1–10 In this small study, the mean healing time was found to be about 4 weeks. Healing rate comparable with the gold standard of TCC coupled with low cost and ease of application has encouraged the authors to implement this technique into daily practice. Larger sample groups will be needed to determine any failure and complication rate associated with this technique.
Initially, variations on the dressing technique were attempted before settling on the method outlined. The authors encountered 1 patient who was a particularly aggressive ambulator and did not use his surgical shoe. He required a mid-week dressing change on 2 occasions. No infections developed during the football dressing therapy, and all dressings were changed at least weekly. All wounds were evaluated and sharp debridement was performed weekly. Moist wound healing was pursued as well as decreasing the bacterial load of the wound with use of a silver primary dressing.
The football dressing seems to limit 1 causal pathway in the formation of the neuropathic forefoot ulcer: trauma. In limiting this factor, wound healing can progress in an expedited fashion similar to that seen with TCC use. The dressing also meets the need for an affordable, readily available, and easily applied forefoot protector that is resistant to patient noncompliance due to its nonremovable nature. In this era of technologically advanced modalities for wound care, the football dressing would seem to be a worthy partner in the battle against the sequelae of neuropathic forefoot ulcerations.