Background
Footwear and offloading techniques are commonly used in clinical practice for the prevention and treatment of foot ulcers in diabetes, but the evidence base to support this use is not well known. The goal of this review was to systematically assess the literature and to determine the available evidence on the use of footwear and offloading interventions for ulcer prevention, ulcer treatment, and plantar pressure reduction in the diabetic foot.
Methods
A search was made for reports on the effectiveness of footwear and offloading interventions in preventing or healing foot ulcers or reducing plantar foot pressure in diabetic patients published prior to May 2006. Both controlled and uncontrolled studies were included. Assessment of the methodological quality of studies and data extraction was independently performed by two reviewers. Interventions were assigned into four subcategories: casting, footwear, surgical offloading and other offloading techniques.
Results
Of 1651 articles identified in the baseline search, 21 controlled studies were selected for grading following full text review. Another 108 uncontrolled and cross-sectional studies were examined. The evidence to support the use of footwear and surgical interventions for the prevention of ulceration is meagre. Evidence was found to support the use of total contact casts and other non-removable modalities for treatment of neuropathic plantar ulcers. More studies are needed to support the use of surgical offloading techniques for ulcer healing. Plantar pressure reduction can be achieved by several modalities including casts, walkers, and therapeutic footwear, but the diversity in methods and materials used limits the comparison of study results.
Conclusions
This systematic review provides support for the use of non-removable devices for healing plantar foot ulcers. Furthermore, more high-quality studies are urgently needed to confirm the promising effects found in both controlled and uncontrolled studies of footwear and offloading interventions designed to prevent ulcers, heal ulcers, or reduce plantar pressure.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/dmrr.850

The effectiveness of footwear and offloading interventions to prevent and heal foot ulcers and reduce plantar pressure in diabetes: a systematic review

Background

Footwear and offloading techniques are commonly used in clinical practice for preventing and healing of foot ulcers in persons with diabetes. The goal of this systematic review is to assess the medical scientific literature on this topic to better inform clinical practice about effective treatment.
Methods

We searched the medical scientific literature indexed in PubMed, EMBASE, CINAHL, and the Cochrane database for original research studies published since 1 May 2006 related to four groups of interventions: (1) casting; (2) footwear; (3) surgical offloading; and (4) other offloading interventions. Primary outcomes were ulcer prevention, ulcer healing, and pressure reduction. We reviewed both controlled and non-controlled studies. Controlled studies were assessed for methodological quality, and extracted key data was presented in evidence and risk of bias tables. Uncontrolled studies were assessed and summarized on a narrative basis. Outcomes are presented and discussed in conjunction with data from our previous systematic review covering the literature from before 1 May 2006.
Results

We included two systematic reviews and meta-analyses, 32 randomized controlled trials, 15 other controlled studies, and another 127 non-controlled studies. Several randomized controlled trials with low risk of bias show the efficacy of therapeutic footwear that demonstrates to relief plantar pressure and is worn by the patient, in the prevention of plantar foot ulcer recurrence. Two meta-analyses show non-removable offloading to be more effective than removable offloading for healing plantar neuropathic forefoot ulcers. Due to the limited number of controlled studies, clear evidence on the efficacy of surgical offloading and felted foam is not yet available. Interestingly, surgical offloading seems more effective in preventing than in healing ulcers. A number of controlled and uncontrolled studies show that plantar pressure can be reduced by several conservative and surgical approaches.
Conclusions

Sufficient evidence of good quality supports the use of non-removable offloading to heal plantar neuropathic forefoot ulcers and therapeutic footwear with demonstrated pressure relief that is worn by the patient to prevent plantar foot ulcer recurrence. The evidence base to support the use of other offloading interventions is still limited and of variable quality. The evidence for the use of interventions to prevent a first foot ulcer or heal ischemic, infected, non-plantar, or proximal foot ulcers is practically non-existent. High-quality controlled studies are needed in these areas.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/dmrr.2702

Footwear and offloading interventions to prevent and heal foot ulcers and reduce plantar pressure in patients with diabetes: a systematic review.

Parametric design of pressure-relieving foot orthosis using statistics-based finite element method

A number of surface scanning systems with the ability to quickly and easily obtain 3D digital representations of the foot are now commercially available. This review aims to present a summary of the reported use of these technologies in footwear development, the design of customised orthotics, and investigations for other ergonomic purposes related to the foot. The PubMed and ScienceDirect databases were searched. Reference lists and experts in the field were also consulted to identify additional articles. Studies in English which had 3D surface scanning of the foot as an integral element of their protocol were included in the review. Thirty-eight articles meeting the search criteria were included. Advantages and disadvantages of using 3D surface scanning systems are highlighted. A meta-analysis of studies using scanners to investigate the changes in foot dimensions during varying levels of weight bearing was carried out. Modern 3D surface scanning systems can obtain accurate and repeatable digital representations of the foot shape and have been successfully used in medical, ergonomic and footwear development applications. The increasing affordability of these systems presents opportunities for researchers investigating the foot and for manufacturers of foot related apparel and devices, particularly those interested in producing items that are customised to the individual. Suggestions are made for future areas of research and for the standardization of the protocols used to produce foot scans.

/pdf/the-use-of-3d-surface-scanning-for-the-measurement-and-326h3o1fkz.pdf

The use of 3D surface scanning for the measurement and assessment of the human foot

For this study, we compared the effectiveness of different design insoles for redistributing pressure during walking for diabetic patients and for normal control subjects. Comparisons of dynamic plantar foot pressure patterns were made with different support, including shoe-only, flat insole, and three contoured insoles. We custom-molded the three contoured insoles by casting the plantar surface of the foot under the conditions of non-weight-bearing, semi-weight-bearing, and full-weight-bearing. With the F-Scan in-shoe system, the interfacial pressure distribution during walking with different plantar supports was measured at 50 Hz for 10 s. The use of insoles could significantly reduce local peak pressure and pressure-time integral and increase the contact area. Contoured insoles were significantly better than flat insoles with regard to the insole functions in reducing local peak pressures. The insole with the semi-weight-bearing foot shape can offer the greatest peak pressure reduction compared to other insole designs, especially for patients with peak pressure located at the second to third metatarsal heads.

/pdf/effectiveness-of-insoles-on-plantar-pressure-redistribution-4se8shav3z.pdf

Effectiveness of insoles on plantar pressure redistribution.

Knowledge of the plantar foot shape alteration under weight bearing can offer implications for the design and construction of a comfortable and functional foot support. The purpose of this study was to quantify the change in three-dimensional foot shape under different weight-bearing conditions. The plantar foot shapes of 16 normal feet were collected by an impression casting method under three weight-bearing conditions: non-weight bearing, semi-weight bearing, and full-weight bearing. An optical digitizing system was used to capture the three-dimensional plantar surface shape of the foot cast. Measurements and comparisons from the digitized shapes were conducted for the whole foot and regions of the foot. The data showed that increased weight bearing significantly increased the contact area, foot length, foot width, and rearfoot width, while it decreased average height, arch height, and arch angle. Compared with the non-weight-bearing foot shape, the semi-weight-bearing condition would produce increases in the contact area of 35.1% +/- 21.6 %, foot length of 2.7% +/- 1.2%, foot width of 2.9% +/- 2.4%, and rearfoot width of 5.9% +/- 4.8%, and decreases in the arch height of 15.4% +/- 7.8% and arch angle of 21.7% +/- 17.2%. The full-weight-bearing condition would produce increases in the contact area of 60.4% +/- 33.2%, foot length of 3.4% +/- 1.3%, foot width of 6.0% +/- 2.1%, and rearfoot width of 8.7% +/- 4.9%, and decreases in the arch height of 20.0% +/- 9.2% and arch angle of 41.2% +/- 16.2%. The findings may be useful for considering the change of foot shape in the selection of shoe size and shoe or insole design.

http://ira.lib.polyu.edu.hk/bitstream/10397/6811/1/Tsung_Plantar_Foot_Shapes.pdf

Quantitative comparison of plantar foot shapes under different weight-bearing conditions

Measurement of lumbar spine loads and motions during rotational mobilization.

This study measured the bending stiffness of the spine when it is subjected to posteroanterior mobilization force. The lumbar spine was modeled as an initially curved beam column supported over the rib cage and the pelvis. Posteroanterior mobilization was assumed to be three-point bending of the beam. The mobilization force was measured by the mounting of a force plate onto the manipulation couch, where electromagnetic sensors measured the change in spinal curvature. The bending stiffness of the spine was derived from the force and curvature data. The technique developed in this study provided highly repeatable data. The theoretical analysis suggests that the pelvic rotation produced by mobilization may be used clinically to indicate the magnitude of the mobilization force. Future research may employ the present method to determine how back pain may affect the bending stiffness of the spine. The bending stiffness values reported in this study will be valuable to future modeling work.

Bending Stiffness of the Lumbar Spine Subjected to Posteroanterior Manipulative Force

/pdf/bending-stiffness-of-the-lumbar-spine-subjected-to-3t9mh54ddi.pdf

Bonnie Y. S. Tsung

Papers

Effectiveness of insoles on plantar pressure redistribution.

Quantitative comparison of plantar foot shapes under different weight-bearing conditions

Measurement of lumbar spine loads and motions during rotational mobilization.

Bending Stiffness of the Lumbar Spine Subjected to Posteroanterior Manipulative Force

Bending stiffness of the lumbar spine subjected to posteroanterior manipulative force