Effects of corrective insole on leg muscle activation and lower extremity alignment in rice farmers with pronated foot: a preliminary report

Abstract

Background: Execution of strenuous activities in conjunction with slippery and viscous muddy working terrain in rice cultivation leads to a high prevalence of farmer musculoskeletal disorders and malalignments. Recommended intervention strategies originally designed for congenitally disabled individuals may also be applicable to farmers, including simple corrective wedges to reduce foot eversion. The objective of the present study was to conduct a preliminary investigation of the effects of corrective wedges on lower extremity muscle activity and alignment when subjects stood on flat rigid ground or muddy terrain, simulating typical work conditions encountered by the unique but populous Thai rice farming workforce. Methods: Nine healthy farmers with pronated feet were recruited to participate and wedges were custom fabricated for each farmer based on physical therapy assessment and use of rapid prototyping techniques. Participants were asked to stand barefoot or with wedges on the two surface types. Results: Results revealed foot pronation and knee valgus to improve (ranging, on average between 5.5 and 16.1 degrees) when participants were equipped with corrective wedges. The muscle activity of the peroneus longus and the tibialis anterior increased for muddy terrain, as compared with the rigid surface. In general, the wedges induced less tibialis anterior activity and greater peroneus longus activity, compared to when participants were standing barefoot. An elevation in evertor muscle activity may reflect stretching of the shortened muscle as a result of the reduced degree of foot pronation. Conclusions: Findings demonstrate potential benefits of corrective insole usage for farmers with pronated feet, including improved lower extremity alignment and invertor muscle activity reduction for both rigid and muddy terrains.

Participatory Ergonomic Interventions for Improving Agricultural Work Environment: A Case Study in a Farming Organization of Korea

“…This study addresses participatory ergonomic interventions recommended for an annual peach farming cycle in a Korean farming organization. Most existing studies focus on interventions for parts of the agricultural work, such as pruning, load carrying, harvesting, and sorting [2,[15][16][17][18][19][20][21][22][23][24][25]. In contrast, an ergonomic analysis was conducted for all tasks performed during the entire agricultural work cycle of peach farming in this study, and interventions were proposed based on the results of the ergonomic analysis.…”

“…Pranav and Patel [16] developed an ergonomic tool for manual harvesting of oranges in hilly regions. Other ergonomic-intervention-related studies include ergo bucket carriers and easy lift [17]; an apple picking bucket [18]; handglove materials for farming activities [19]; magnifier inspection, a lift assist system, and a smokeless method for calming bees in apiculture [20]; corrective insoles [21]; ergonomic baskets for tealeaf plucking [22]; and ergonomic interventions for weeding, weighing beef calves, and growing vegetables [23][24][25]. Fathallah [2] reviewed the extent of MSDs in agriculture and employed a historic perspective on how ergonomic interventions have been used to reduce the health effects of labor-intensive agriculture.…”

Satisfaction with Orthopedic Treatments

“…In a review found in the literature, it is shown that in adults with different pathologies such as cavus foot, rheumatoid arthritis (RA), the custom-made foot orthosis reduces the patient's pain [4].…”

“…There are numerous studies found in the literature that evaluate the efficacy of plantar orthoses, but all are focused on certain pathologies or alterations, most of these studies are focused on treating very specific alterations of the foot [4][5][6][7].…”

An exploration of the effects of prefabricated and customized insoles on lower limb kinetics and kinematics during walking, stepping up and down tasks: A time series analysis

“…Some authors employ low-cost prefabricated insoles which only consider foot size [1,2]. In contrast, others consider customizing prefabricated insoles by adding medial or lateral wedges [3,4], and custom-made insoles manufactured through foot casting aim to position the subtalar joint in neutral [5,6]. There are many prescriptions for insoles with different purposes that have been researched and used clinically.…”