Beliefs and Use of Forefoot Lateral Wedging in Podiatric Practice: A Survey of Podiatrists in Aotearoa New Zealand

Background There is currently limited evidence exploring the beliefs and application of forefoot lateral wedges in clinical practice by podiatrists. The study aimed to understand rationale and beliefs that guided the use of forefoot lateral wedges amongst Aotearoa New Zealand podiatrists. Methods A cross-sectional study of Aotearoa New Zealand podiatrists was conducted between 31st May 2021 and 26th July 2021. Data were collected anonymously using a web-based survey platform. The 30-item survey included questions to elicit participant characteristics, why and when podiatrists used orthotic modifications, what biomechanical assumptions influenced clinical decision making, and how podiatrists fabricated and placed forefoot lateral wedging. The survey findings were reported using descriptive statistics. Results Sixty-five podiatrists completed the survey. Most respondents were trained in Aotearoa New Zealand (91%), had over 10 years’ experience (70%), and worked with a mixed case load (60%). Seventy-seven percent (77%) prescribed 0 to 10 pairs of foot orthoses per week, with forefoot lateral wedges used in 44% of prescriptions. Forefoot lateral wedges were likely to be used in the treatment of peroneal tendon injuries (70%) and chronic ankle instability (64%). The most common belief being that forefoot lateral wedges increase first metatarsophalangeal joint range of motion (86%). Forefoot lateral wedges were regularly manufactured from 3mm (74%), medium density ethylene vinyl acetate (91%) and positioned from the calcaneo-cuboid joint (53%) to the sulcus (77%). Conclusion New Zealand podiatrists frequently use forefoot lateral wedges in clinical practice. Respondents were predominately guided by the underpinning belief that forefoot lateral wedging reduces tissue stress and have their greatest functional impact on first metatarsophalangeal joint range of motion. Forefoot lateral wedges are commonly manufactured from 3mm ethylene vinyl acetate, although it is important to be aware that this will translate to differing angles, dependant on width. Further research should be undertaken to explore the influence of forefoot lateral wedges on forefoot function and the effect of wedge length.

Immediate Effects of Using Insoles With Various Wedges on Plantar Pressure Measurements and Comfort Level During Marching

Background: Orthotic devices like insoles are widely used to improve performance. This study investigated whether immediate effects of using insoles with various wedges influence on plantar pressure measurements and comfort level during marching.Methods: Twenty five able-bodied males participated in this study voluntarily. Repeated measures analysis of variance test with a Bonferroni correction (P<0.0014) was used to compare dependent variables among nine insole wedge conditions.Results: The result of present study showed that the comfort level was non-significantly higher in the anterior and medial wedges compared to the posterior-lateral and anterior-lateral wedges during marching (P>0.0014). The peak of plantar pressure and impulse in the first to third metatarsal regions decreased in the anterior, medial and anterior-medial wedges compared to the lateral and posterior-lateral wedges (P<0.0014). In addition, a significant negative relation between the comfort level and plantar pressure measurements was observed in the second and third metatarsals and midfoot regions during marching (P<0.05).Conclusion: It seems that using anterior, medial and anterior-medial wedge for insole may have some advantage through increasing comfort sense and decreasing the risk of stress fracture injuries in the second and third metatarsal regions. These findings should be considered during designation of shoes or insoles for military environments.

Biomechanical Effect of 3D-Printed Foot Orthoses in Patients with Knee Osteoarthritis

Background: Lateral wedges comprise a common conservative treatment for medial knee osteoarthritis (OA). However, use of lateral wedges might increases the ankle eversion moment. To minimize the risk of ankle joint, lateral wedges with custom arch support are suggested. However, the manufacturing process of a custom foot orthosis (FO) is complicated, labor intensive, and time consuming. The technology of 3D printing is an ideal method for mass customization. Therefore. the purpose of this study was to develop custom FOs using 3D printing techniques and to evaluate the biomechanical effects of 3D-printed FOs in patients with medial knee OA.Methods: Fifteen patients with medial knee OA were enrolled into this study. Kinematic and kinetic data were collected during walking by using an optical motion capture system. A paired-sample t-test was conducted to compare biomechanical variables under two conditions: walking in standard shoes (Shoe) and walking in shoes embedded with 3D-printed FOs (Shoe + FO).Results: Under the Shoe + FO condition, the center of pressure at the peak knee adduction moment significantly shifted laterally by 2.71 mm compared with the Shoe condition. No significant difference in the peak knee flexion moment was observed between the two conditions. In addition, both the first and second peak knee adduction moments were significantly reduced by 4.08% and 9.09% under the Shoe + FO condition. The 3D-printed FOs did not affect the ankle eversion moment but caused a decrease in the peak ankle inversion moment.Conclusions: The 3D-printed FOs caused a decrease in the ankle inversion moment, the first and second peak knee adduction moments by changing the center of pressure path laterally. Although the decrease in the knee flexion moment from the use of 3D-printed FOs was nonsignificant, such FOs engender biomechanical changes and positively influence the biomechanics of patients with knee OA.

Immediate effects of using insoles with various wedges on plantar pressure measurements and comfort level during marching.

Background: Orthotic devices like insoles are widely used to improve performance. This study investigated whether immediate effects of using insoles with various wedges influence on plantar pressure measurements and comfort level during marching.Methods: Twenty-five (n=25) able-bodied males participated in this study voluntarily. Repeated measures analysis of variance test with a Bonferroni correction (P<0.0014) was used to compare dependent variables among nine insole wedge conditions.Results: The result of present study showed that the comfort level was non-significantly higher in the anterior and medial wedges compared to the posterior-lateral and anterior-lateral wedges during marching (P>0.0014). The peak of plantar pressure and impulse in the first to third metatarsal regions decreased in the anterior, medial and anterior-medial wedges compared to the lateral and posterior-lateral wedges (P<0.0014). In addition, a significant negative relation between the comfort level and plantar pressure measurements was observed in the second and third metatarsals and midfoot regions during marching (P<0.05).Conclusion: It seems that using anterior, medial and anterior-medial wedge for insole may have some advantage through increasing comfort sense and decreasing the risk of stress fracture injuries in the second and third metatarsal regions. These findings should be considered during designation of shoes or insoles for military environments.

Effects of Lateral and Medial Wedged Insoles on Knee and Ankle Internal Joint Moments During Walking in Healthy Men

Background: Wedged insoles have been used to treat knee pathologies and to prevent injuries. Although they have received much attention for the study of knee injury, the effects of wedges on ankle joint biomechanics are not well understood. This study sought to evaluate the immediate effects of lateral and medial wedges on knee and ankle internal joint loading and center of pressure (CoP) in men during walking. Methods: Twenty-one healthy men walked at 1.4 m/sec in five footwear conditions: neutral, 6° (LW6) and 9° (LW9) lateral wedges, and 6° (MW6) and 9° (MW9) medial wedges. Peak internal knee abduction moments and angular impulses, internal ankle inversion moments and angular impulses, and mediolateral CoP were analyzed. Analysis of variance with post hoc analysis and Pearson correlations were performed to detect differences between conditions. Results: No differences in internal knee joint loading were found between neutral and any of the wedge conditions. However, as the wedge angle increased from medial to lateral, the internal ankle inversion moment (LW6: P = .020; LW9: P &lt; .001; MW6: P = .046; MW9: P &lt; .001) and angular impulse (LW9: P = .012) increased, and the CoP shifted laterally (LW9: P &lt; .001) and medially (MW9: P &lt; .001) compared with the neutral condition. Conclusions: Neither lateral nor medial wedges were effective in altering internal knee joint loading during walking. However, the greater internal ankle inversion moment and angular impulse observed with lateral wedges could lead to a higher risk of ankle injury. Thus, caution should be taken when lateral wedges need to be prescribed.