A Guide To Preventative Offloading Of Diabetic Foot Ulcers
Charcot restraint orthotic walker. The CROW boot is a device composed of polypropylene material lined with Plastazote. It incorporates a total contact custom orthotic and utilizes a rocker-bottom sole. The CROW is the treatment of choice for many during the second and third stages of Charcot neuroarthropathy to maintain joint stability and alignment. One main advantage is that the clinician can remove the boot, treat the ulcer and reapply the boot during office visits. One can control edema with the boot, which allows the patient to ambulate. A disadvantage of the CROW boot is removability as the patient may not be compliant and may remove the brace at any time. The CROW boot may also require frequent adjustments due to changes in lower extremity edema.12
The prefabricated walker was originally designed to treat fractures and sprains. One may also use the CROW to offload DFUs. Hanft and co-workers showed a healing rate of 85 percent within 13 weeks with an average time to closure of 5.51 weeks (+/- 1.02 weeks) during a retrospective study of more than 300 patients with plantar DFUs.12 Some of the prefabricated walkers contain polyethylene plugs that one can remove to offload a particular area where an ulcer may reside. Advantages of these devices are similar to the CROW boot because one can easily remove the prefab walkers.12
Integrated prosthetic and orthotic system (IPOS). The IPOS model is designed for forefoot ulcerations. This “half shoe” has 10 degrees of dorsiflexion and a heel that is elevated 4 cm so the forefoot does not contact the ground. Patients who wear the IPOS often have difficulty with balance. Due to the dorsiflexion of the device, many patients with diabetes are unable to wear the shoe.12
The OrthoWedge shoe (Darco) is very similar to the IPOS model with the exception of the sole extending to the toes. The patient’s ability to dorsiflex the ankle is an issue as well. One study has shown plantar pressure reduction of 64 to 66 percent although the OrthoWedge was less effective than the total contact cast.12 The healing sandal is a total contact orthotic made of Plastazote. The ulcerated area contains a cutout for offloading and the edges are skived to minimize stress. Hanft and colleagues showed a healing rate of 74 percent within 13 weeks and an average time to closure of 7.11 weeks (+/-2.35 weeks).10 The healing sandal is lightweight but has poor control over foot motion, which elevates the risk of increasing stress at the ulceration site.
How To Improve Adherence With Offloading Modalities
While there are certainly offloading modalities our wound care patients cannot physically remove, the majority of what we provide are removable. In 2003, researchers discovered that the notion of non-adherence plays a much larger role in the delayed healing of diabetic ulcers than once believed. Armstrong and colleagues revealed that patients with removable offloading devices spent 40 percent of their daily steps without appropriate offloading in comparison to control patients with non-removable devices.14
Research suggests that several factors play contribute to non-adherent behavior in patients. For instance, patients may blame the size of the particular device while others place blame on the difficulty of applying the device. Other patients may have work-related shoe restrictions or jobs that require constant ambulation. Furthermore, socioeconomic status may play a role as many patients may be the sole provider for their families and may be unable to take time off from work. Other studies have supported the idea that the presence of an offloading device may negatively affect the patient’s ability to ambulate or maintain self-reliance.15 Whatever the case may be, researchers have recommended that early identification and evaluation of potential psychosocial issues may render a higher adherence rate and enhance clinical outcomes.15