Current Concepts In Total Contact Casting For DFUs
Why Is The TCC So Effective?
Total contact casting has the ability to reduce plantar pressures, reduce shear, restrict ankle motion, shorten stride length and force adherence. Birke and coworkers reported that a total contact cast reduced pressures at the metatarsal heads in six normal, healthy patients by up to 84 percent.22 In a study comparing the TCC to running shoes, Hartsell and colleagues identified a 65 percent reduction in forefoot plantar pressures in the cast.23 Additionally, this study reported excellent reproducibility of load redistribution with TCC applications spaced one week apart and applied by the same technician. Wertsch and colleagues found a decrease in pressure in the first metatarsal head by 69 percent and in the heel by 45 percent with the use of a TCC.24
Although we do not currently have the ability to measure shear, one applies the TCC with intimate contact layers to the foot and leg, preventing motion within the cast. This close contact also increases the area of weight distribution, including the large surface area of the leg. This creates a “cone effect” or as we describe it to patients, “like putting a cork back into a wine bottle.” When patients stand on this cast, the leg portion of the cast itself takes a portion of their weight. This fixed ankle cast now eliminates the propulsive phase of gait and prevents the forces of equinus, which are common in our patients with diabetes.
As with most treatments, adherence is critical. Armstrong and colleagues proved that just making a controlled ankle motion (CAM) cast non-removable increased the rate of healing from 51.9 to 82.6 percent healed in 12 weeks.25
Overcoming The Hurdles To Using Total Contact Casts
So why don’t we see 3 million people in our country with total contact casts on their feet? In a 2008 study by Wu and coworkers that surveyed 895 podiatrists who perform diabetic wound care, only 1.7 percent employed the TCC for the majority of their diabetic foot ulcerations.26
The number of users is climbing, however, as sales of total contact cast kits are anecdotally showing a marked increase in the last few years. Total contact casting is also one of the few treatments that has had an increase in Medicare reimbursement to its providers.
The common excuses for not using the TCC are: knowledge and time of application, reimbursement issues, and the fear of creating additional wounds. These are just that — excuses. Total contact casting has been available for many years and is now available in kits with instructions. An even easier “roll-on” version is now available. The TCC-EZ (Derma Sciences) provides comparable efficacy to the standard TCC and is truly easier to apply.
In 2005, Guyton and colleagues addressed the issue of safety, concluding that “A frequently changed total contact cast is a safe modality for the offloading and immobilization of the neuropathic foot, albeit with an expected constant rate of minor, reversible complications.”27
Snyder and coworkers stated that “From a practical standpoint, more widespread adoption of effective offloading modalities would make the most positive improvement in DFU treatment.”28 In 2008, Warriner said, “This year, if there were only two things that we could institute in our 300 wound centers, it would be the following: 1. Non-invasive vascular assessment testing on new patients, 2. Offloading and shear reduction for diabetic foot ulcers utilizing the total contact cast.”29