Following the Evidence for Total Contact Casting as First-Line Treatment of DFUs in the Wound Clinic

This article discusses one busy metropolitan clinic’s successful implementation of TCC in response to evidence supporting offloading as a standard of care for diabetic foot ulcerations. 

Diabetic foot ulcers (DFUs) are a major concern in the outpatient wound clinic due to the growing diabetes epidemic, the significant morbidity and mortality associated with DFUs, and the economic burden on the healthcare system. Despite a well-established standard of care for DFUs, which includes effective offloading as a cornerstone, there are gaps in practice with regard to clinical implementation of appropriate offloading. This article will provide a discussion of the evidence supporting the use of offloading as a standard of care for DFUs with a focus on total contact casting (TCC). In addition, we will discuss barriers to using TCC in clinical practice followed by an example of how one heavily trafficked wound clinic located in Texas has successfully implemented TCC and has experienced a positive impact on wound healing rates as well as clinic efficiency.

DFU DETAILS 

As many as 25% of patients living with diabetes will develop a wound in their lifetime.¹ DFUs precede 85% of all nontraumatic lower extremity amputations,² and the five-year mortality rate following a neuropathic ulcer is about 45%.³ This mortality rate is higher than that associated with colon cancer, ischemic ulcers, peripheral arterial disease, lung cancer, or pancreatic cancer.⁴ DFUs pose a serious economic burden on our society. In the United States, from 2006–10, DFUs accounted for more than 1 million emergency department (ED) visits; 702,692 inpatient stays; 34,708 major above-the-ankle amputations; 75,932 minor amputations; and 18,355 deaths.⁵ The related cost for ED visits and inpatient care for DFU complications was approximately $8.78 billion.⁵ With the growing diabetes epidemic and the impact of DFUs on patient outcomes and the healthcare system, the effective management of DFUs has become crucial.

Problem: DFUs ARE DIFFICULT

DFUs are the result of neuropathic and vascular complications of diabetes. Diabetes-induced nerve damage causes peripheral neuropathy. In turn, the loss of protective sensation prevents the patient from being aware of pressure from shoes, cuts, bruises, or any injury to the foot. Diabetes-induced vascular disease affects the very small blood vessels supplying the skin (microangiopathy) to the point that some patients may experience ischemia. This lack of healthy blood flow also contributes to ulceration and impaired wound healing.⁶ The healing of DFUs is complicated due to the intricate cascade of interdigitated local and systemic factors involved in the process, as demonstrated by a study that found nearly 70% of DFUs still had not healed after 20 weeks of standard wound care.⁷ 

Solution: EFFECTIVE OFFLOADING

Offloading is a major treatment consideration for DFUs and should be combined with standard care recommendations, including glucose control, promotion of revascularization, debridement, moist wound healing, and infection surveillance and management.^8-12 The recently published TCC consensus document¹² recommends consideration of the “VIPs” (vascular, infection, and pressure) and that pressure be addressed through offloading. Various methods of offloading may be used, including removable devices (eg, custom-made footwear, postoperative shoe, shoe modification, half-shoe, walkers, etc.); non-removable devices (eg, TCC); and other assistive devices such as wheelchairs and crutches or activities (eg, bed rest). Each modality has its pros and cons as well as varying levels of supporting evidence. Regardless, the efficacy of any offloading strategy is greatly dependent on patient adherence.¹² This author chooses TCC as the first line of treatment for DFUs whenever possible.

TCC PARAMETERS  

TCC works by redistributing pressure away from the plantar surface and redirecting body weight from the foot to the lower leg. In essence, a fine balance must be achieved whereby plantar load is reduced to allow ulcer healing while maintaining the patient’s ambulatory ability. In addition, by locking the ankle at 90^o of flexion, TCC eliminates the propulsive phase of gait, shortens stride length, decreases walking velocity, and diminishes both shear and vertical forces. Pressure mapping studies^13-15 have shown effective offloading is achieved with TCC. One study¹³ has found TCC decreases pressure in the fifth, fourth, and first metatarsal heads by 32%, 63%, and 69%, respectively, and decreases heel pressure by 45%. Thus, TCC successfully eliminates shear and pressure forces while its custom fit accommodates volume changes in the patient’s foot and leg over time. Furthermore, a recent study¹⁶ demonstrated the suspension of the foot by the considerable load-bearing capacity of the TCC walls contributes to the pressure reduction and redistribution properties of TCC. 

In addition, data suggest the use of TCC as part of a protocol of care for DFUs may provide other salutary effects on the wound. A study of TCC versus no cast¹⁷ revealed a significantly greater prevalence of inflammatory elements such as hyperkeratosis, fibrosis, and cellular debris in control patient wounds (P <0.05). In contrast, a significantly higher prevalence of reparative elements, such as cutaneous annexes, capillaries, and granulating tissue, were found in TCC-managed wounds (P <0.01).¹⁷ These results suggest the use of TCC impacts both the micro- and macro-environments of the wound. Studies^18-24 have demonstrated the clinical efficacy of TCC, making it the “gold standard” for offloading. In a randomized, controlled clinical trial²⁴ comparing TCC, a healing sandal (HS), and a shear-reducing walking boot (SRB) Lavery et al found 88.9% of wounds healed with TCC versus 50% with the HS and 40% with the SRB. Furthermore, the mean time to healing was 5.34 weeks with TCC versus 8.9 weeks for HS and 6.7 weeks for SRB.²⁴ One of the most important features of TCC is that it’s nonremovable, which ensures patient compliance with offloading and further proves its contributions to superior outcomes compared to removable devices.¹⁸ To this end, studies have shown the most effective way for a removable device to produce healing outcomes comparable to TCC is for it to be made nonremovable. ^20,25

Based on the compelling amount of data, a recent consensus document recommends TCC as the preferred method for offloading plantar DFUs because it has most consistently demonstrated the best healing outcomes.¹² Simply put, adequate offloading increases the likelihood of DFU healing. The addition of advance modalities is often required for DFUs to achieve closure, but these are unlikely to succeed in improving wound healing outcomes unless combined with effective offloading.¹² From a cost perspective, the use of TCC has a significant impact, as DFU management on average costs about half ($11, 946 in the United States) of standard care without TCC ($22,494).²⁶ The advantage of healing the DFU more quickly also improves patient and caregiver quality of life, decreases the risk of complications, and decreases burden on the healthcare system.²⁷ TCC is a reimbursable procedure comparable to frequently used debridements for hospital outpatient departments (HOPDs) and private offices. The procedure code for TCC is 29445. The 2016 national average Medicare allowable payment rate for HOPDs is $208.88. In HOPDs, 29445 has a status indicator of “S,” meaning it’s separately payable and not discounted when multiple procedures are performed. However, when two procedures are performed during the same HOPD encounter, the provider must consult the current quarter’s National Correct Coding Initiative (NCCI) edits to verify whether or not the edits will allow Medicare payment for both procedures. The 2016 national average Medicare allowable payment rate for physicians who personally apply TCC in an HOPD is $107.05. Similar to HOPDs, if physicians perform two procedures during the same encounter, they must check the current quarter’s NCCI edits to verify whether or not the edits will allow Medicare payment for both procedures. 

Problem: TCC UNDERUTILIZATION

Despite extensive clinical evidence documenting the efficacy of TCC, there exists a “gap” between the evidence and its use in clinical practice. This is demonstrated by a recent retrospective study by the U.S. Wound Registry (USWR) that found only 3.7% of “TCC-eligible” patients received TCC.²⁸

Barriers to TCC use can be clinician, patient, and/or organization-related. Clinician-related barriers can include insufficient training, misperception that TCC delays healing, staff-training barriers, and cost and time versus reimbursement.^12,29,30 TCC does require training on proper application, and therefore requires a time and resource commitment to learn and practice. Patient-related barriers can include reluctance, transportation issues (eg, driving inability), being overweight, and a fear of falling. Organization-related barriers can include cost, difficulty being integrated into patient flow, and storage of supplies.^28-30 

Lastly, there are potential risks to patients, such as iatrogenic ulcers, issues from gait instability created by limb length discrepancy, and falls, which can discourage some clinicians.²⁶ Wound care practitioners must help to increase awareness and utilization of this highly effective treatment modality. The evidence consistently shows when offloading is integrated into the patient-encounter process and provided at each visit, the likelihood of DFU healing increases and the chance of complications decreases.¹²

One Solution: TCC System 

One of the main barriers associated with the use of TCC is that it’s considered to be “cumbersome and time consuming.” However, one clinic that recently implemented the roll-on TCC-EZ^® Total Contact Casting System (Derma Sciences Inc., Princeton, NJ), a newer-generation TCC that offers easier application and removal, experienced positive outcomes that further support USWR data among clinics that used this roll-on cast.²⁸

TCC is perceived as difficult to apply, but roll-on casts require minimal training and can be applied quickly, freeing up time to allow more patients to be seen. This roll-on cast has an average time to apply of < 10 minutes³¹ and patients can bear weight in about 15 minutes versus traditional TCC, which takes about 30-45 minutes to dry.³⁰ This ease of application can help minimize training time and facilitate wound clinic adoption. As far as storage space, the cast kits keep all supplies in one box.

WOUND CLINIC CASE EXAMPLE 

Located in a tertiary-care, inner-city hospital, the wound care clinic referenced within this article sees a complex patient population including those living with multiple comorbidities (eg, poorly managed diabetes, renal disease, severe peripheral arterial disease and transplant patients). Some patients live with nondiabetic neuropathy that is idiopathic or related to alcohol use, HIV, spinal stenosis, or para/quadriplegia. Wound clinic staff began casting in 2010 and at that time saw approximately 40 patients per day. Productivity has steadily increased and in 2015 the clinic was seeing 50-60 patients per day. DFUs represented 19% of the clinic’s patient population in 2015. Success has been seen in casting plantar DFUs, and casting has helped close wounds to patients’ heels and toes as well as post-surgical transmetatarsal amputation (TMA) wounds. The inclusion of Charcot, TMA, and extra-large boots has also helped include patients that may not have other options.

The clinic has also observed a marked impact following the integration of the newer TCC technology into the protocol of care for DFUs, with a healing rate for DFUs of 93% in 2015 and an average duration to heal a DFU of 59 days in 2015 versus 71 days in 2014 (Figure 1). Furthermore, the healing rates at the clinic are higher than the average healing rate of other clinics utilizing the same electronic health record tracking software for all wound types, with a healing rate of 93% versus 79%, specifically for DFUs (Figure 2). 

Patient satisfaction: This is important to consider, as adherence is key to the success of TCC. In this clinic’s experience, some patients return in months or years with new DFUs and, after experiencing success with a previous casting modality, they embrace the need to be casted before their wound gets too large, now knowing they will wear a cast for a few weeks if initiated early. There are patients living with DFUs who are not casted for such reasons as unstable ambulation/safety, need to drive, or outright refusal. 

Clinic efficiency: In this author’s experience, negative pressure wound therapy (NPWT) and TCC have the greatest impact on outcomes for patients, and both possess an education element for healthcare staff. Similar to NPWT, while there is a learning curve involved with starting use of TCC, this should not influence the decision to utilize this modality when treating DFUs. Providers at the clinic mentioned in this article cast approximately 10-16 patients per day. With regards to time to cast, this aligns with literature citing an average time to apply of < 10 minutes. Following staff training, each member of the clinic is fully competent to apply and remove TCC-EZ. This clinic has implemented TCC-EZ as a standard of care for DFUs and has since increased productivity while increasing the number of casted patients and achieving higher healing rates.

CONCLUSION

Further research could provide additional information and quantitative assessment of the potential cost implications of implementing TCC in a wound clinic, such as the impact on the use of other advanced modalities including hyperbaric oxygen treatments and antibiotic use. Cost impact on patients, such as out-of-pocket costs for visits as well as missed work time and overall healthcare costs, are other areas to study. While implementation of a TCC system into practice takes time and organization, the benefits are significant and numerous, and the opportunity to improve patient outcomes with this proven treatment modality is most advantageous for the individual, the clinic, and the wound care sector. 

Andrew J. Applewhite has served as a consultant for Derma Sciences Inc., Princeton, NJ, and is on staff at a Texas-based wound clinic. 
Michele Rosen, senior clinical resource specialist at Derma Sciences Inc., contributed to this article.

References

1. Singh N, Armstrong DG, Lipsky BA. Preventing foot ulcers in patients with diabetes. JAMA. 2005;293(2):217-28.

2. Pecoraro RE, Reiber GE, Burgess EM. Pathways to diabetic limb amputation. Basis for prevention. Diabetes Care. 1990;13(5):513-21.

3. Moulik PK, Mtonga R, Gill GV. Amputation and mortality in new-onset diabetic foot ulcers stratified by etiology. Diabetes Care. 2003;26(2):491-94.

4. Armstrong DG, Wrobel J, Robbins JM. Guest Editorial: are diabetes-related wounds and amputations worse than cancer? Int Wound J. 2007;4(4):286-87.

5. Skrepnek GH, Mills JL, Sr, Armstrong DG. A diabetic emergency one million feet long: disparities and burdens of illness among diabetic foot ulcer cases within emergency departments in the United States, 2006-2010. PLoS One. 2015;10(8):e0134914.

6. Barshes NR, Sigireddi M, Wrobel JS, et al. The system of care for the diabetic foot: objectives, outcomes, and opportunities. Diabet Foot Ankle. 2013;4. doi: 10.3402/dfa.v4i0.21847

7. Margolis DJ, Kantor J, Berlin JA. Healing of diabetic neuropathic foot ulcers receiving standard treatment. A meta-analysis. Diabetes Care. 1999;22(5):692-95.

8.  Yazdanpanah L, Nasiri M, Adarvishi S. Literature review on the management of diabetic foot ulcer. World J Diabetes. 2015;6(1):37-53.

9. Braun L, Kim PJ, Margolis D, Peters EJ, Lavery LA; Wound Healing Society. What's new in the literature: an update of new research since the original WHS diabetic foot ulcer guidelines in 2006. Wound Repair Regen. 2014;22(5):594-604.

INTEGRATING TCC INTO YOUR WOUND CLINIC

When introducing any new treatment modality, it’s important to ensure aprocess is confirmed with respect to assessment and application. Education andtraining of staff is also crucial.   At the clinic referenced in this article, a heavily trafficked facility located inTexas, staff members were taught how to apply and remove the cast by a manufacturer’srepresentative. The consensus was that clinicians felt comfortable following2-3 applications with supervision. The current process for casting startswith a nurse taking the patient into the room, removing the cast, and measuringand assessing the wound. The physician then assesses and recommends treatmentbefore the nurse applies wound dressing(s), per doctor’s orders, and thecast, except for the last roll-on portion, which the physician performs. Patientsthen sit in the waiting room while the cast dries (Figure 3 and Figure 4).

All patients are casted in the prone position, as suggested by the manufacturer,because it offers better offloading biomechanics due to the calf muscleposition. The cast also dries faster in the foot and ankle area, and is much easierto assure a 90o angle of the ankle when applied in the prone position.32,33Specifically, the posterior calf muscle mass shifts proximally on the leg, givinga better fit32 and maximizing the cone effect.34 Also, the prone position hasbeen shown to prevent edema16 and high-pressure areas in the cast while allowingthe leg to be held up easily.33-35

Patient education is provided directly as well as through the use of brochuresand websites to help ensure patients are comfortable when not in theclinic and are taking necessary steps to care for their casts.30 There can besome reluctance among those being casted for the first time, but taking thetime to explain that the modality offers their best healing option has provenhelpful. Additionally, if patients are aware of the high morbidity and mortalityrates associated with DFUs they are generally more motivated to comply.There have been times when patients who’ve experienced a chronic DFU inthe past will begin to experience another ulcer and will ask for a cast to beinitiated before the wound progresses. 

— Andrew J. Applewhite, MD, CWSP, UHM