Pressure Off-Loading Devices (Total Contact Casting) and Footwear
The key to successful pressure reduction in diabetic foot problems is patient adherence to an offloading device. These devices protect the wound and facilitate healing by decreasing pressure over the wound. Modalities for offloading include Total Contact Casting (TCCs), crutches, walkers, wheelchairs, removable cast walkers, and various types of footwear.
TCCs are the most common offloading technique, employing a well-molded, minimally padded cast that maintains contact with the entire sole of the foot and lower leg. They have been shown to reduce pressure by 84%-92% at ulceration sites. Advantages of TCCs include protection of the foot from infection and reduction or control of edema. Disadvantages include difficulty to apply, skin irritation, and potential struggles faced by the patient in daily life activities such as sleeping comfortably and bathing without getting the cast wet. Contraindications of TCCs are infected wounds as well as wounds with ischemia or osteomylitis.
Removable cast walkers were designed as “instant” total contact casts free from the disadvantages of TCCs. They make it easier to take part in daily tasks and to self-inspect the wound and apply topical therapies. They may also be used for infected wounds or superficial ulcers.
Crutches, walkers, and wheelchairs can also offer complete offloading of wounds. However, they require upper body strength and endurance, placing unaffected limbs at risk by increasing pressure on them.
Various types of offloading footwear include:
- Scotchcast boot: This removable, lightweight, easy-to-apply boot is made to fit each individual foot with a window cut at the ulceration site. It is an inexpensive option that protects the wound and the foot, reduces pressure on the lesion, and maintains patient mobility.
- Half shoes: This lightweight, removable offloading device was designed to decrease pressure on the forefoot postoperatively. Although removable and inexpensive, it takes a significant amount of time to manufacture and apply.
- Healing sandals: This specially designed sandal has a rigid rocker, hook-and-loop closures, and a conforming cover for the forefoot.
- Felted footwear: This commonly used offloading device uses a bilateral felt-foam pad over the sole of the foot with a gap corresponding to the ulcer site.
Therapeutic footwear may also be prescribed to facilitate the healing of superficial ulcers. However, it is not an offloading device.