A quantitative assessment of healing sandals and postoperative shoes in offloading the neuropathic diabetic foot

Diabetic foot ulcers: Classification, risk factors and management

Diabetic foot ulceration is a devastating complication of diabetes that is associated with infection, amputation, and death, and is affecting increasing numbers of patients with diabetes mellitus. The pathogenesis of foot ulcers is complex, and different factors play major roles in different stages. The refractory nature of foot ulcer is reflected in that even after healing there is still a high recurrence rate and amputation rate, which means that management and nursing plans need to be considered carefully. The importance of establishment of measures for prevention and management of DFU has been emphasized. Therefore, a validated and appropriate DFU classification matching the progression is necessary for clinical diagnosis and management. In the first part of this review, we list several commonly used classification systems and describe their application conditions, scope, strengths, and limitations; in the second part, we briefly introduce the common risk factors for DFU, such as neuropathy, peripheral artery disease, foot deformities, diabetes complications, and obesity. Focusing on the relationship between the risk factors and DFU progression may facilitate prevention and timely management; in the last part, we emphasize the importance of preventive education, characterize several of the most frequently used management approaches, including glycemic control, exercise, offloading, and infection control, and call for taking into account and weighing the quality of life during the formulation of treatment plans. Multidisciplinary intervention and management of diabetic foot ulcers (DFUs) based on the effective and systematic combination of these three components will contribute to the prevention and treatment of DFUs, and improve their prognosis.

A comparison of two designs of postoperative shoe for hallux valgus surgery: A biomechanical study in a cadaveric model

BACKGROUND

Hallux Valgus Surgery success depends not only on the operative technique, but also on the care of the foot during the postoperative period. Orthopedic shoes have been developed to decrease the weight load on the first ray, an excess of which might lead to a loss of fixation or pseudoarthrosis. The goal of this study was to determine how the load distribution changed as the forced applied to the foot increased, with and without an orthopedic shoe. Also, we compared to different shoe models.

METHODS

Pressure sensors were placed under the first metatarsal head and the heel of twenty specimens of fresh cadaveric adult feet. Two orthopedic shoes were chosen, a double padded (MS) and a reverse camber shoe (RCS). 10 kg loads were progressively applied, up to 60 kg. We first compared three instances: no shoe, MS and RCS. A secondary analysis comparing barefoot versus shoes was performed. A mean comparison was performed (ANOVA/T-student).

RESULTS

The mean pressure of the heed and the first metatarsal showed that there were significant differences between groups (P < .005). The secondary analysis (no shoe vs orthopedic shoes) showed that the pressure without shoe was significantly higher than with any orthopedic shoe (P < .005). There were no statistically significant differences between models of shoes (P = .402).

CONCLUSION

After a surgical procedure for hallux valgus fixation, postoperative shoes should be indicated to decrease the pressure on the first metatarsal head and heel in order to avoid an overload of the postoperative area.

LEVEL OF EVIDENCE

Cadaveric study. Level V.

The Evaluation of Foot Rockers on the Kinematic Parameters of Individuals With Diabetes

BACKGROUND

A variety of shoe modifications have been used to reduce the forces applied on the plantar surface of the foot in those with diabetes. Toe and heel rockers are 2 of the most common types used. The aim of this study is to evaluate the effect of these shoe modifications on the kinematics of both normal and diabetic individuals.

METHOD

Two groups of healthy and diabetic individuals were recruited for this study. The Qualysis motion analysis system was used to record the motions of participants while walking with shoes with toe and a combination of toe and heel rockers (combined). The effects of the type of rockers used and the effect of groups were determined using MANOVA.

RESULTS

Results of the study demonstrated no discernible difference between the spatiotemporal and range of motion of the ankle, knee, and hip joints while walking with a toe and combined rockers. There was also no difference between healthy and diabetic individuals in relation to these parameters (P value >.05).

CONCLUSION

Results of this study demonstrated no difference between the spatiotemporal and range of motion of lower-limb joints in healthy and diabetic individuals when walking with toe and combined rockers. Because the use of these rockers did not influence the kinematics of the joints while walking, it is recommended that they be used for this group of individuals if they influence the forces applied on the foot.

LEVELS OF EVIDENCE

Level IV.

Offloading the diabetic and ischemic foot: solutions for the vascular specialist

For generations, the use of techniques to defer skin pressure and protect the lower-extremity wound has been a cardinal goal to achieve therapeutic success and healing. Choosing the appropriate postoperative offloading device or shoe is often difficult, as it is challenging to merge optimal mechanical protection with clinical realities and patient needs. The gold standard for offloading remains the total contact cast, yet it receives minimal utilization in the clinical setting. Other devices have shown benefit, including the removable cast walker, instant total contact cast, and depth inlay shoes, for preventative measures. Ultimately, any plantar, lower-extremity wound must receive some form of external pressure reduction to reach acceptable rates of healing. Future technologies will aid these measures by providing body-worn constant monitoring systems and more effective offloading via patient-specific exoskeletons. This review is a supplemental update on the available wound offloading modalities based on logic-driven research regarding pressure relief across the diabetic neuropathic or impaired perfusion foot.

Plantar pressure relief using a forefoot offloading shoe

AIM

To assess the effectiveness of the Barouk(®) second-generation postoperative forefoot relief shoes during appropriate use of the shoe on healthy subjects.

MATERIALS AND METHODS

A convenience sample of 35 volunteer subjects (17 women, 18 men) was recruited to participate in this study. Dynamic foot loading was evaluated with inshoe plantar pressure measurements. Subjects were asked to walk two trials at a self-selected speed: (a) in their mass-produced shoes to assess baseline pressure values, defined as 100% and (b) with the Barouk(®) postoperative shoe on the right foot and their own shoe on the left side. Data analysis was tested for statistical differences with paired Student's t-tests (with p<0.05 as a significance level).

RESULTS

The Barouk(®) second-generation postoperative forefoot relief shoes relieved forefoot pressure in all trials. For all 35 volunteers, there was a 79-96% mean peak pressure reduction (p<0.001) of the forefoot except for the fifth metatarsal head during appropriate use of the postoperative shoe. In contrast to the results for the forefoot, a significant increase of the peak pressure values was observed in the heel region. Similar findings were observed for the pressure-time integral values.

CONCLUSION

The data of our study provide evidence that the second-generation Barouk(®) shoe relieve pressure of the forefoot with appropriate use.

Preliminary investigation on the reduction of plantar loading pressure with different insole materials (SRP--Slow Recovery Poron, P--Poron, PPF--Poron +Plastazote, firm and PPS--Poron+Plastazote, soft)

BACKGROUND

The aim of this study is to investigate the amount of pressure reduction for different padding and insole materials commonly used in the podiatry clinic.

METHODS

Plantar pressure were taken for 5 subjects without insoles fitted (BF) in their daily sports shoes, and thereafter with 4 pairs of simple insoles (6.4 mm thick) each as follow: SRP - Slow Recovery Poron, P - Poron, PPF - Poron+Plastazote (firm) and PPS - Poron+Plastazote (soft). In addition, subjects were also tested with semi-compressed felt (SCF) padding with a 1st metatarsophalangeal joint (MTPJ) aperture cut-out bilaterally. Minimum, maximum, mean pressure and peak pressure at the hallux, 1st, 2nd, 3rd/4th and 5th MTPJ across both feet were analysed. Repeated measures ANOVA with post hoc Bonferroni paired wise comparison was used to test for any statistical significance at the 95% confidence level for all pressure data.

RESULTS

PPF was significant in reducing the minimum (p<0.005) and mean pressure (p<0.03) when compared to BF. This accounted for approximately 28% and 27% pressure reduction in minimum and mean pressure respectively. Peak pressure on the 1st MTPJ locality showed significant reduction of 37% and 29% with the use of SCF (p<0.004) and PPF (p<0.004), respectively.

CONCLUSIONS

All 4 commonly used insole materials were able to reduce pressure across the whole foot with PPF achieving significance. Off-loading the 1st MTPJ would still be best achieved with the commonly used plantar metatarsal pad of SCF with the aperture cut-out design.

Plantar pressure relief in the diabetic foot using forefoot offloading shoes

PURPOSE

Forefoot offloading shoes (FOS) are commonly used in clinical practice for treatment of plantar forefoot ulcers in the diabetic foot. The aim of this study was to assess the offloading efficacy of four different FOS models in comparison with a cast shoe and control shoe.

METHODS

In-shoe plantar pressures were measured during walking in each of the six footwear conditions in 24 neuropathic diabetic patients at high risk for plantar foot ulceration. For each of six foot regions, peak pressure, pressure-time integral, and force-time integral were calculated. Load transfer diagrams were developed to assess the footwear mechanisms of action. Perceived walking comfort was measured using a visual analogue scale (VAS). All comparisons between conditions were tested at P<0.05.

RESULTS

Peak pressures and pressure-time integrals at the metatarsal heads and hallux regions were significantly reduced (by 38-58%) in all FOS models when compared with the control shoe. The FOS also relieved metatarsal head peak pressure to a significantly larger extent than the cast shoe (approximately 20%). The load transfer diagrams showed a major transfer of approximately 40% of forefoot load to the midfoot explaining the offloading efficacy of the FOS. Perceived walking comfort was significantly lower in the FOS (VAS score 2.7-5.9) when compared with the control shoe (VAS 8.2) and cast shoe (VAS 6.8).

CONCLUSIONS

The data showed that all FOS models were effective in their primary goal, relieving forefoot pressure in at-risk neuropathic diabetic patients. Therefore, these shoes may be effective in offloading and healing plantar forefoot ulcers, although the low comfort scores should be considered as this may potentially affect adherence to treatment.

The Role of Activity, Adherence, and Off-Loading on the Healing of Diabetic Foot Wounds

The etiology of diabetic foot ulcerations is commonly associated with the presence of peripheral neuropathy and repetitive trauma due to normal walking activities to areas of the foot exposed to moderate or high pressure. The goal of any treatment plan should include as a central tenet the mitigation or modulation of this activity and/or pressure. While numerous studies have detailed the potential pressure off-loading properties of various treatment modalities, subsequent studies have suggested that, if easily removable, these therapies will likely not be used for the majority of steps taken each day. This serves to explain at least in part the often disappointing results of both these pressure off-loading technologies and advanced wound-healing therapies. This article reviews these data and suggests that an amalgam of effective pressure relief coupled with strategies to reduce nonadherence to this therapy could yield a potentially favorable clinical result.

The pivotal role of offloading in the management of neuropathic foot ulceration

Lower extremity amputations among persons with diabetes are generally preceded by neuropathic foot ulcerations. Healing of diabetic ulcerations in a timely manner is of central importance in any plan for amputation prevention. With sufficient vascular supply, appropriate débridement, and infection control, the primary mode of healing a diabetic neuropathic foot ulcer is pressure dispersion. The total contact cast has been deemed by many to be the gold standard in offloading; however, modification of a standard removable cast walker to ensure patient compliance may be as efficacious in healing diabetic foot ulcers as the total contact cast. Combining an effective, easy to use offloading device that ensures patient compliance with advanced wound healing modalities may form a formidable team in healing ulcers and potentially averting lower limb amputations.

Treatment for diabetic foot ulcers

People with diabetes develop foot ulcers because of neuropathy (sensory, motor, and autonomic deficits), ischaemia, or both. The initiating injury may be from acute mechanical or thermal trauma or from repetitively or continuously applied mechanical stress. Patients with clinically significant limb ischaemia should be assessed by a vascular surgeon to determine the need for angioplasty, stenting, or femorodistal bypass. When infection complicates a foot ulcer, the combination can be limb or life-threatening. Infection is defined clinically, but wound cultures reveal the causative pathogens. Tissue specimens are strongly preferred to wound swabs for wound cultures. Antimicrobial therapy should be guided by culture results, and should aim to cure the infection, not to heal the wound. Alleviation of the mechanical load on ulcers (off-loading) should always be a part of treatment. Neuropathic ulcers typically heal in 6 weeks with total contact casting, because it effectively relieves pressure at the ulcer site and enforces patient compliance. The success of other approaches to off-loading similarly depends on the patients' adherence to the effectiveness of pressure relief. Surgery to heal ulcers and prevent recurrence can include tenotomy, tendon lengthening, reconstruction, or removal of bony prominences. However, these procedures may result in secondary ulceration and other complications. Ulcer recurrence rates are high, but appropriate education for patients, the provision of posthealing footwear, and regular foot care can reduce rates of re-ulceration.

It's not what you put on, but what you take off: techniques for debriding and off-loading the diabetic foot wound

The basic etiology of neuropathic diabetic foot wounds involves pressure in conjunction with cycles of repetitive stress, leading to failure of skin and soft tissue. The central tenet of any treatment plan addressing neuropathic diabetic foot wounds is the appropriate debridement of nonviable tissue coupled with adequate pressure relief (off-loading). Although numerous advances have been made in the treatment of diabetic foot wounds, including bioengineered tissues, autologous and exogenous cytokine delivery systems, and potentially effective topical antimicrobial modalities, none will succeed without addressing effective debridement and off-loading. Specific debridement and off-loading techniques are discussed, along with available supporting evidence. This includes the use of the "instant" total contact cast, among other modalities.

Comparison of forefoot ulcer healing using alternative off-loading methods in patients with diabetes mellitus

OBJECTIVE

To compare the healing rate of forefoot ulcers in patients with diabetes treated using a total contact cast with those treated using alternative off-loading methods. DESIGN Retrospective analysis of healing rates of forefoot ulcers.

SETTING

Louisiana State University Health Sciences Center Diabetes Foot Program, Baton Rouge, LA.

PARTICIPANTS

120 consecutive patients with diabetes mellitus referred for treatment of new, nonsurgical forefoot ulceration.

INTERVENTIONS

Alternative off-loading methods (an accommodative dressing, a healing shoe, a walking splint) or a total contact cast.

MAIN OUTCOME MEASURE

Healing time of forefoot ulcers in days and percentage healed in 12 weeks.

RESULTS

113 of 120 (94%) patients with forefoot ulcers healed in an average of 45.5 +/- 43.4 days. Seven of 120 (5.8%) patients with ulcers either did not heal or were lost to follow-up. Stepwise lognormal regression showed ulcer grade (P <.001, R(2)= 0.11) and width (P =.024, R(2)= 0.05) were significantly related to healing time. After adding ulcer grade (1, 2, or 3) and width into the model, there was no difference between healing time in the accommodative dressing (P =.253), healing shoe (P =.815), and walking splint (P =.525) when compared with the total contact cast. Forefoot ulcers were closed within 12 weeks in at least 81% of cases irrespective of the off-loading method.

CONCLUSION

The healing rate of forefoot ulcerations in patients with diabetes using alternative off-loading methods or a total contact cast appeared to be comparable when the method was selected based on location of ulcer, patient age, and duration of ulceration.

Patient Compliance: Its Relevance to the Management of a Patient With Charcot’s Foot

This case report discusses the challenges related to the management of a diabetic patient with Charcot’sfoot and a neuropathic foot ulcer. The patient received good coordinated care including foot pressure measurements. The case is an example demonstrating that patient compliance is a determinant of treatment outcome.

Pneumatic bracing and total contact casting have equivocal effects on plantar pressure relief

The purpose was to examine and compare plantar pressures produced in healthy subjects while wearing a running shoe (RS), total contact cast (TCC) and 'customized' pneumatic pre-fabricated walking brace (PWB). A repeated measures design was used to compare the plantar pressures recorded for three footwear types (RS, TCC, PWB) in two body regions (forefoot, heel). Nine healthy subjects walked at a self-selected walking pace on a motorized treadmill while wearing the RS, TCC and PWB (ordered randomization). Following a five-minute acclimatization period on the treadmill with each footwear device, plantar pressures were recorded from 84 constant gait speed and step length steps using the Pedar system of in-shoe array of capacitive sensors embedded in an insert. Mean spatially averaged peak plantar pressures were recorded for the metatarsal heads and heel region for each footwear device worn by each subject. A two-way analysis of variance with repeated measures and post-hoc Tukey tests analysed the data with a significance level of p=.05. The main effects of footwear (p=.005) and body region (p=.000), and interaction effect (body region x footwear device) (p=.000) were significant. Unloading of the forefoot was 63.72% and 58.77% for the TCC and PWB, respectively, whereas loading under the heel was increased 37.09% and 34.11% for the same two devices, respectively. Patients who develop neuropathic plantar ulcers in the forefoot region, but not in the heel region, may benefit from a reduction in plantar pressures by using either the TCC or a 'customized' PWB. An alternative footwear device still needs to be found for those patients with heel ulceration.

Quantitative assessment of simultaneous capacitive and resistive plantar pressure measurements during walking

Plantar pressure data were collected simultaneously, during walking, from capacitive and resistive in-shoe pressure measurement systems. Overall mean peak pressure recordings from the resistive system were 32%, 20% and 14% greater than recordings from the capacitive system, at the heel, central metatarsal heads, and great toe, respectively. Placement of one system's insoles above or below the other's somewhat affected peak pressure measurements from both systems, while calibration via air bladder or single limb standing techniques somewhat affected resistive measurements as well. Capacitive measurement variability was 60%, 20% and 22% lower than resistive measurement variability, at the heel, central metatarsal heads, and great toe, respectively. Both systems tended to exhibit greater variability when capacitive insoles were placed above resistive insoles; however, the effects on variability of the experimental insole arrangements were well overshadowed by the overall variability differences between systems.

Orthotic intervention in patients with diabetic foot ulceration

A review of the evidence of the causes of diabetic foot ulceration and the importance of prevention strategies.

The effect of increased weight on peak pressures: implications for obesity and diabetic foot pathology

The purpose of this study was to determine if increased weight contributes to increased mean peak plantar foot pressures when foot function, deformity, and structure are controlled. Ten male and nine female volunteers without sensory neuropathy or other systemic disease were evaluated in the study. Using a repeated measures design, peak plantar foot pressures were compared using the Novel Pedar in-shoe pressure measurement system under three conditions. Baseline measurements were made while volunteers wore the standard test footwear, a thin-soled rubber oxford sneaker. The second and third test conditions involved pressure measurements with an additional 9.1 kg (20 lb) and 18.2 kg (40 lb), respectively, of weight evenly distributed in pockets on the front and back of a workout vest. There was a significant increase in mean peak plantar foot pressures under the metatarsal heads, heel, and midfoot for each incremental increase of weight (baseline vs. 9.1 kg, p < .05; 9.1 kg vs. 18.2 kg, p < .05). The authors conclude that increases in weight increased plantar foot pressures for the first metatarsal, lesser metatarsal, midfoot, and heel regions in both men and women.