Medial Midfoot Research Articles

Predictive Radiographic Values for Foot Ulceration in Persons with Charcot Foot Divided by Lateral or Medial Midfoot Deformity.

Background: To identify differences in radiographic outcomes in weight-bearing lateral X-ray to predict the probability of ulceration in patients with midfoot Charcot neuroarthropathy (CN) differentiated by lateral and medial column deformities. Methods: Thirty-five patients who suffered from CN midfoot deformity participated in this 1 year prospective study in a specialized diabetic foot unit. Lateral talar-first metatarsal angle, calcaneal pitch, and cuboid height were performed by digital radiographs in the weight-bearing lateral view. Patients were followed up for 1 year or until an ulcer ulceration event occurred in the midfoot region. Results: ROC analyses showed that all patients with medial pattern deformity that developed a midfoot ulcer had a lateral talar-first metatarsal angle greater (negative) than −27.5 degrees (°). All patients with lateral pattern deformity that developed a midfoot ulcer had a calcaneal pitch greater (more negative) than −5° and a cuboid height greater (more negative) than −1.5°. Conclusions: Lateral talar-first metatarsal angle was the greatest predictor of midfoot ulceration, with greater than −27.5° measurement correlating with ulceration occurrence in patients with medial deformity. Calcaneal pitch and cuboid height were the greatest predictors of midfoot ulceration with greater than −5 and −1.5°, respectively in patients with CN lateral deformity.

Lag Screw with Plantar Plating for Naviculocuneiform Arthrodesis in Progressive Collapsing Foot Deformity

Category:Midfoot/ForefootIntroduction/Purpose:Medial column procedures are a common adjunct to progressive collapsing foot deformity (PCFD) correction. In particular, naviculocuneiform (NC) arthrodesis could be performed when degeneration or instability at the NC joint is contributing to arch collapse. Plantar plate fusion resists gapping along the tension side of the joint, potentially reducing risk of non-union and recurrent deformity. Additionally, by placing the hardware in a plantar location there is an increased soft tissue envelope to function in a protective matter and eliminate the possibility of hardware prominence and tendon irritation. The purpose of this study was to analyze short-term clinical and radiographic outcomes of NC fusion using a lag screw with plantar plating technique.Methods:A single-surgeon retrospective case series was performed on patients with PCFD and medial arch collapse treated with NC arthrodesis using a lag screw plus plantar plating technique between January 2016 and December 2019, with a minimum six month clinical and radiographic follow up. Patients undergoing revision NC joint arthrodesis, patients with incomplete imaging, or an arthrodesis technique that did not utilize NC joint plantar plating were excluded. Demographic data, perioperative data, complications, and reoperations were recorded from electronic medical records. Pre-operative AOFAS midfoot scores were calculated at the initial clinic visit and then again at the patients' most recent follow-up. In the case of most recent follow up occurring prior to six months post-operatively, a telemedicine visit was performed. Anteroposterior (AP) and lateral talo-first metatarsal angles, talonavicular coverage angle, and calcaneal pitch were measured independently by three authors. Fusion was confirmed radiographically and computed topography when union was in question.Results:Nineteen patients (15 female, 4 male; 11 right, 8 left) with a mean age of 56.6 years and a mean follow-up of 21.0 +- 13.4 months were reviewed. A mean 3.4 concomitant procedures were performed at the time of NC fusion. AP talo-first metatarsal angle (18.9° to 5.2°), lateral talo-first metatarsal angel (-18.7° to -4.4°), talonavicular coverage angle (28.1° to 7.4°), and calcaneal pitch (14.6° to 20.1°) all improved significantly (p<0.001). Fusion was confirmed in 15 (79%) patients at a mean 6.1 +- 3.5 months. Mean AOFAS midfoot scores improved from 51.7 +- 13.0 preoperatively to 82.6 +-12.8 (p<0.001) at an average 21.0 +- 13.4 months follow up. Two patients experienced broken hardware, one patient fractured through flexor digitorum longus (FDL) transfer site and experienced non-union requiring revision at 9.5 months, one patient experienced symptomatic lateral column hardware requiring removal, and one patient experienced non-union requiring revision at 13.5 months.Conclusion:Lag screw with plantar plating is a technique for NC arthrodesis that is associated with a higher non-union rate (21%) than what is reported in the literature. Nonetheless, at short term (mean 21 months) follow up, the technique proved capable of correcting medial arch collapse through the NC joint when used in conjunction with adjunctive soft tissue and bony procedures. Plantar plating technique resulted in no instances of symptomatic hardware along the medial midfoot. Addressing medial arch collapse with NC arthrodesis resulted in significant improvement of both radiographic outcomes and patient reported clinical outcomes.

方向転換動作における足部アーチ変形の定量化

In order to improve performance and prevent foot disorders, it is necessary to understand the characteristics of the foot deformation and to study the relationship between mechanical properties. However, most studies regarding the foot deformation and mechanical properties during movement have focused on walking and running along a straight line, and there are no studies on lateral movements such as cutting maneuver, which are usually seen in ball games. The aim of this study was to investigate the effect of changes of direction angle on foot arch deformation by quantifying foot arch deformation during cutting maneuver, which are expected to have different deformation characteristics compared to walking and straight running. The results of this study suggest that: 1. they have different deformation patterns during ground contact between the medial longitudinal arch, and midfoot and forefoot transverse arch; 2. compared with straight running, the deformation of the medial longitudinal arch increased, and the deformation of the midfoot and forefoot transverse arch decreased during cutting maneuver.

Longitudinal study of foot pressures during real-world walking as infants develop from new to confident walkers

BackgroundOnset of walking in infants leads to regular cyclic loading of the plantar foot surface for the first time. This is a critical period for evolving motor skills and foot structure and function. Plantar pressure literature typically studies gait only once walking is established and under conditions that artificially constrain the walking direction and bouts compared to how infants move in the real-world. We therefore do not know how the foot is loaded when self-directed walking is first achieved and whether it changes as walking is practiced.Research questionHow do pressures on the plantar foot in real-world walking change from new to confident walking?MethodsFifty-seven infants participated in a two-site longitudinal study. Bespoke child-friendly spaces incorporated large pressure platforms and video. Data was collected at two milestones: new (403 days) and confident (481 days) walking. Steps were defined as walking straight or turning medially/laterally. Pressure variables were calculated for eight-foot regions and compared between milestones.ResultsConfident walking resulted in more steps (median: 18 v 35) and almost twice as many turning steps. During straight-line steps, confident walking increased peak pressures in the medial heel (median: 99.3 v 106.7kPa, p < .05) and lateral forefoot (median: 53.9 v 65.3kPa, p < .001) and reduced medial toe pressure (median: 98.1 v 80.0kPa, p < .05). Relative medial midfoot contact area reduced (median: 12.4 v 11.2%, p < .05) as absolute foot contact increased. A faster transition across stance and a reduced relative contact time in the forefoot were recorded in confident walking.SignificancePressures change rapidly as walking is initiated with significant differences in foot loading evident within an average 77 days. Importantly, these changes differ in straight and turning walking. Continued reliance on assessment of straight-line walking during early stages of ambulation likely fails to characterise 26% of steps experienced by infant feet.

Effects of footwear cushioning on leg and longitudinal arch stiffness during running

During running, humans increase leg stiffness on more compliant surfaces through an in-series spring relationship to maintain constant support mechanics. Following this notion, the compliant midsole material of standard footwear may cause individuals to increase leg stiffness while running, especially in footwear with very thick midsoles. Recently, researchers have also proposed that footwear stiffness can affect the stiffness of the foot’s longitudinal arch (LA) via a similar mechanism. To test these ideas, we used 3D motion capture to record 20 participants running on a forceplate-instrumented treadmill while barefoot, and while wearing three types of sandals composed of materials ranging an order of magnitude in Young’s modulus: ethylene vinyl acetate (EVA), and two varieties of polyurethane rubber (R30 and R60). We calculated leg stiffness using standard methods, and measured LA stiffness based on medial midfoot kinematics. While there was an overall significant effect of footwear on leg stiffness (P = 0.047), post-hoc tests revealed no significant differences among individual pairs of conditions, and there was no effect of footwear on LA stiffness. However, participants exhibited significantly greater LA compression when barefoot than when running in EVA (P = 0.004) or R30 (P = 0.036) sandals. These results indicate that standard footwear midsole materials are too stiff to appreciably affect leg stiffness during running, meaning that increasing midsole thickness is unlikely to cause individuals to alter their leg stiffness. However, use of footwear does cause individuals to restrict LA compression when compared to running barefoot, and further research is needed to understand why.

The immediate effects of hallux valgus orthoses: A comparison of orthosis designs.

Hallux valgus orthoses are available in a wide range of designs and materials, but the effects of their design on functional performance have not been fully investigated. This present study aims to comprehensively analyze the immediate effects of soft and semi-rigid hallux valgus orthoses on balance, plantar pressure, hallux valgus angle, and subjective sensations. Sixteen female subjects have participated in the study, including 10 subjects with healthy feet and 6 with hallux valgus. Three conditions are tested, including in the barefoot and using two types of commercially available hallux valgus orthoses. The subjects participate in static and dynamic (walking) tests with the use of the Novel Pedar® system. The peak pressure values in the hallux, lateral toes, first metatarsophalangeal joint, 2-4th metatarsal heads, 5th metatarsal head, medial midfoot, lateral midfoot and rearfoot in the various foot conditions are examined and compared. The hallux valgus angle of each subject is measured based on their footprint. Their subjective feelings towards the orthoses are also evaluated. A repeated-measures analysis of variance, and independent-sample t-test are performed. The correction of the hallux valgus angle is statistically significant when the subjects with hallux valgus use the orthoses. In comparing the two types of orthoses, the use of the orthosis made of soft materials results in correction in the hallux valgus angle and higher wear comfort, and lower plantar pressure in hallux area. The results provide insights into the design of hallux valgus orthoses, thus offering practical reference for the selection of hallux valgus orthosis with compromise between functional performance and wear comfort.

Comparison of the immediate effects of prefabricated soft medical insoles and custom-molded rigid medical insoles on plantar pressure distribution in athletes with flexible flatfoot: a prospective study

Background: The aims of this quasi-experimental study were to compare the effect of prefabricated soft medical insoles and custom-molded rigid medical insoles on plantar pressure distribution in athletes with flexible flatfoot. Methods: Eighteen amateur athletes with flexible flatfoot participated in this study. All participants received custom-molded rigid medical insoles and prefabricated soft medical insoles. Mean peak pressure (kPa), maximum force (N), and contact area (cm2) were calculated for the heel, medial and lateral midfoot, first metatarsal head, second and third metatarsal heads, fourth and fifth metatarsal heads, hallux, and other toe area using the Pedar-X system (Novel GmbH, Munich, Germany) immediately. Results: The use of both prefabricated and custom-molded insoles significantly reduced the mean pressure and force in the heel, second and third metatarsophalangeal joints (MTP2,3), the fourth and fifth metatarsophalangeal joints (MTP4,5), and increased the pressure in the medial midfoot compared to the shoe (P&lt;0.001). No significant difference was observed between the two insoles (P&gt;0.05). The contact area increased significantly in the medial midfoot (P&lt;0.001) and MTP2,3 (P=0.02) and decreased in the hallux (P&lt;0.001) and other toes (P=0.01) using both insoles compared to only shoes. Conclusions: The results showed that the use of a medical insole in athletes with flexible flatfoot could alter athletics’ plantar pressures immediately. Since both insoles had a similar effect on the distribution of plantar pressures, it seems that the prefabricated soft medical insole is a more suitable option for daily use in athletes to prevent injury because of its availability and cost-effectiveness. Level of Evidence: Level II.

A Three-Dimensional Printed Foot Orthosis for Flexible Flatfoot: An Exploratory Biomechanical Study on Arch Support Reinforcement and Undercut.

The advancement of 3D printing and scanning technology enables the digitalization and customization of foot orthosis with better accuracy. However, customized insoles require rectification to direct control and/or correct foot deformity, particularly flatfoot. In this exploratory study, we aimed at two design rectification features (arch stiffness and arch height) using three sets of customized 3D-printed arch support insoles (R+U+, R+U−, and R−U+). The arch support stiffness could be with or without reinforcement (R+/−) and the arch height may or may not have an additional elevation, undercutting (U+/−), which were compared to the control (no insole). Ten collegiate participants (four males and six females) with flexible flatfoot were recruited for gait analysis on foot kinematics, vertical ground reaction force, and plantar pressure parameters. A randomized crossover trial was conducted on the four conditions and analyzed using the Friedman test with pairwise Wilcoxon signed-rank test. Compared to the control, there were significant increases in peak ankle dorsiflexion and peak pressure at the medial midfoot region, accompanied by a significant reduction in peak pressure at the hindfoot region for the insole conditions. In addition, the insoles tended to control hindfoot eversion and forefoot abduction though the effects were not significant. An insole with stronger support features (R+U+) did not necessarily produce more favorable outcomes, probably due to over-cutting or impingement. The outcome of this study provides additional data to assist the design rectification process. Future studies should consider a larger sample size with stratified flatfoot features and covariating ankle flexibility while incorporating more design features, particularly medial insole postings.

The Concurrent Validity, Test-Retest Reliability and Usability of a New Foot Temperature Monitoring System for Persons with Diabetes at High Risk of Foot Ulceration.

At-home foot temperature monitoring may be useful in the early recognition of imminent foot ulcers that occur through biomechanical loading in people with diabetes. We assessed the concurrent validity, test–retest reliability, and usability of a new plantar foot temperature monitoring device in 50 people with diabetes and peripheral neuropathy. We compared plantar foot temperature measurements with a platform system that consists of embedded temperature sensors with those from a handheld infrared thermometer that was used as a reference. Repeated platform assessments were compared for test–retest reliability. Usability was assessed in 15 participants who used both devices daily for two weeks at home, after which they completed a questionnaire. Agreement between devices was excellent for the metatarsal heads and heel (ICCs ≥ 0.98, LOA: −0.89 °C; 1.16 °C) and hallux and lateral midfoot (0.93 ≤ ICC ≤ 0.96, LOA: −2.87 °C; 2.2 °C), good for digits 2–5 (0.75 ≤ ICC ≤ 0.88, LOA: −5.04 °C; 2.76 °C), and poor for the medial midfoot (ICC = 0.19, LOA: −8.21 °C; −0.05 °C). Test–retest reliability was high (ICC = 0.99, LOA: −0.59 °C; 1.35 °C). Participants scored between 3.8 and 4.3 on a 5-point Likert scale for willingness to measure, ease of use, measurement comfort, and duration. In conclusion, the platform shows good concurrent validity in foot regions where most ulcers occur, good test–retest reliability, and good usability for measuring plantar foot temperature. Further research should assess the clinical validity of the platform to help prevent plantar diabetic foot ulcers.

Plantar Pressure Variations Induced by Experimental Malocclusion-A Pilot Case Series Study.

Background: All body systems involved in ensuring a healthy posture (musculoskeletal system, oculomotor, oto-vestibular and occluso-cranial-mandibular) are essential in maintaining postural balance. Research Question: Does experimental malocclusion in subjects in static position determine variations in plantar pressure? Methods: Overall, 31 subjects were included in the study. The plantar pressure was evaluated in five different points: lateral and medial heel, midfoot, 1st and 5th metatarsal area. Using a specially designed splint, an artificial malocclusion was induced on the right hemimandibular arch. The pressure was measured at 0 (T0), 15 (T1) and 30 min (T2) after splint application. Results: The right external plantar sensors recorded statistically significant differences in pressure values after 15 min of splint wear (5th metatarsal area, p = 0.05; midfoot, p = 0.04). Important pressure values were also recorded by the left internal plantar sensors (1st metatarsal, p = 0.01; medial heel, p = 0.006), after 30 min of splint wear. Conclusions: Asymmetrical experimental malocclusion produces early changes in plantar pressure, a proof of compensatory mechanisms induced by secondary postural imbalance.

Foot Posture and Plantar Loading With Ankle Bracing.

Arch height is one important aspect of foot posture. An estimated 20% of the population has pes planus and 20% has pes cavus. These abnormal foot postures can alter lower extremity kinematics and plantar loading and contribute to injury risk. Ankle bracing is commonly used in sport to prevent these injuries, but no researchers have examined the effects of ankle bracing on plantar loading. To evaluate the effects of ankle braces on plantar loading during athletic tasks. Cross-sectional study. Laboratory. A total of 36 participants (11 men, 25 women; age = 23.1 ± 2.5 years, height = 1.72 ± 0.09 m, mass = 66.3 ± 14.7 kg) were recruited for this study. Participants completed walking, running, and cutting tasks in 3 bracing conditions: no brace, lace-up ankle-support brace, and semirigid brace. We analyzed the plantar-loading variables of contact area, maximum force, and force-time integral for 2 midfoot and 3 forefoot regions and assessed the displacement of the center of pressure. A 3 × 3 mixed-model repeated-measures analysis of variance was used to determine the effects of brace and foot type (α = .05). Foot type affected force measures in the middle (P range = .003-.047) and the medial side of the foot (P range = .004-.04) in all tasks. Brace type affected contact area in the medial midfoot during walking (P = .005) and cutting (P = .01) tasks, maximum force in the medial and lateral midfoot during all tasks (P < .001), and force-time integral in the medial midfoot during all tasks (P < .001). Portions of the center-of-pressure displacement were affected by brace wear in both the medial-lateral and anterior-posterior directions (P range = .001-.049). Ankle braces can be worn to redistribute plantar loading. Additional research should be done to evaluate their effectiveness in injury prevention.

Subtalar Arthroereisis for Flexible Flatfoot in Children—Clinical, Radiographic and Pedobarographic Outcome Comparing Three Different Methods

Subtalar arthroereises (STA) is a minimally invasive and reversible surgery to correct symptomatic flexible flatfoot (FFF) in children. Various techniques were described either applying expandable sinus tarsi implants or lateral calcaneus stop screws. Studies comparing the outcome of STA with different devices are rare. This retrospective single-center cohort study analyzes the results of STA using three different implants. 113 STA were performed in 73 consecutive patients (28 females). Mean age at surgery was 10.8 years (range 5–16). Mean follow-up was 29.0 months (range 1–111). In 21 feet the non-absorbable Kalix® endorthesis and in 56 feet the absorbable Giannini endorthesis were applied. Subtalar extraarticular screw arthroereises (SESA) was conducted in 36 feet. Clinical, radiographic and pedobarographic parameters were analyzed. No intraoperative complications were observed. All three procedures achieved comparable improvements of the clinical, radiographic and pedobarographic parameters. The mean foot function index (FFI) improved from 36.4 (range 12–63) to 22.8 (range 2–55). The mean preoperative calcaneal inclination angle and the lateral talocalcaneal angle improved from 9.5° (range 0–22) and 42.3° (range 21–62) to 12.8° (range 0–26) and 37.6° (range 15–56), respectively. Pedobarographically determined values of the arch index, the medial midfoot contact area and the medial forefoot peak pressure decreased. In contrast to SESA (1/36, 3%), a higher incidence of implant-related complications was observed using Kalix® (6/21, 29%) and Giannini (10/56, 8%) sinus tarsi implants. Peroneal muscle contractures only occurred in the SESA group (4/36, 11%). Premature removal due to treatment-related complications was necessary in 6/21 Kalix® implants (29%), 4/56 Giannini implants (7%) and 4/36 SESA implants (11%). Implant choice for treatment of painful FFF in children with STA seems to play a subordinate role. Clinical, radiographic and pedobarographic outcomes are comparable between the applied implants. Surgeons and patients should be aware of the different spectrum of implant-related complications. Treatment can be reliably monitored by radiation-free pedobarography providing dynamic information about the deformity.

Mass-Like Fat at the Medial Midfoot: A Common Pseudolesion.

Background Fatty masses are common and may be encountered in the foot and ankle. In some cases, normal subcutaneous fat may be mistaken for a discrete mass. Aims The aim of this study was to evaluate the common finding of prominent subcutaneous fat at the medial midfoot resembling a lipoma and to determine the prevalence of this pseudolesion by applying a series of potential size cutoff criteria. Materials and Methods Three musculoskeletal radiologists retrospectively evaluated 91 sequentially performed magnetic resonance imaging examinations of the ankle to measure fat resembling a discrete lipoma at the medial midfoot. Each blinded reader measured the largest area of continuous subcutaneous fat in orthogonal axial, coronal craniocaudal, and coronal transverse dimensions. Patient age, sex, and study indications were also recorded. Statistical analysis was performed with R and SAS 9.4 software Results A discrete fatty pseudolesion as defined by measuring at least 1 cm in all planes by measurements of at least two of three readers was present in 87% of cases (79 of 91). When a size criterion of 1.5 cm was used, a pseudolesion was documented in 14% of cases (13 of 91). There was a significant correlation between larger pseudolesion size and female sex in the axial plane; however, there was no correlation in the coronal craniocaudal and coronal transverse dimensions. Conclusions Subcutaneous fat at the medial midfoot often has a mass-like appearance that could be mistaken for a lipoma. It is important to recognize this pseudolesion variant and not to confuse the imaging appearance for a discrete mass.

Dynamic plantar pressure patterns in children and adolescents with Charcot-Marie-Tooth disease

BackgroundThe dynamic plantar pressure patterns of children and adolescents with Charcot-Marie-Tooth (CMT) disease and its relationship to musculoskeletal alterations may help to understand the natural history of the disease and improve therapeutic interventions. Research questionThe study compared dynamic plantar pressure patterns in children and adolescents with and without CMT. It also tested the associations between isometric muscle strength (IMS), passive range of motion (ROM), foot posture and dynamic plantar pressure patterns in CMT. MethodsThis cross-sectional study compared children and adolescents (aged 8–18 years) with CMT (n = 40) with a typical group (n = 40). The plantar pressure distribution during gait was recorded, and the contact area (CA), peak pressure (PP), contact time (CT) and pressure-time integral (PTI) in five foot regions (rearfoot, midfoot lateral, midfoot medial, lateral forefoot and medial forefoot) were analysed. The IMS of the dorsiflexors and plantar flexors, passive ROM, and foot posture were also recorded. ResultsPP (medial midfoot and medial forefoot) and PTI (rearfoot, lateral midfoot and medial forefoot) were higher in children with CMT compared with the typical group. The adolescents with CMT presented a less CA (whole foot) and a higher CT (medial midfoot) when compared with typical group. For CMT, in the medial midfoot, plantar flexor IMS associated with PP (β=-11.54, p = 0.01) and PTI (β=-3.38, p = 0.04); supinated foot posture associated with PP (β = 33.89, p = 0.03) and PTI (β = 12.01, p = 0.03). SignificanceChildren with CMT showed clear changes in most of the dynamic plantar pressure variables, while adolescents with CMT showed changes mostly in CA and CT. This information together with the associations established between supinated foot, dorsiflexion ROM and plantar flexions IMS can be useful for guiding rehabilitation professionals in their therapies.

The Use of Infrared Thermography to Develop and Assess a Wearable Sock and Monitor Foot Temperature in Diabetic Subjects.

One important health problem that could affect diabetics is diabetic foot syndrome, as risk of ulceration, neuropathy, ischemia and infection. Unnoticed minor injuries, subsequent infection and ulceration may end in a foot amputation. Preliminary studies have shown a relationship between increased skin temperature and asymmetries between the same regions of both feet. In the preulceration phase, to develop a smart device able to control the temperature of these types of patients to avoid this risk might be very useful. A statistical analysis has been carried out with a sample of foot temperature data obtained from 93 individuals, of whom 44 are diabetics and 49 nondiabetics and among them 43% are men and 57% are women. Data obtained with a thermographic camera has been successful in providing a set of regions of interest, where the temperature could influence the individual, and the behavior of several variables that could affect these subjects provides a mathematical model. Finally, an in-depth analysis of existing sensors situated in those positions, namely, heel, medial midfoot, first metatarsal head, fifth metatarsal head, and first toe has allowed for the development of a smart sock to store temperatures obtained every few minutes in a mobile device.

Evaluation and Management of Common Accessory Ossicles of the Foot and Ankle in Children and Adolescents.

Accessory ossicles are a common radiographic finding about the foot and ankle in children and adolescents. They are often noted incidentally during evaluation of foot and ankle injuries, and most can be managed nonsurgically. Although over 20 accessory ossicles have been described around the foot and ankle, five specific structures generate the most concern in pediatric patients. An accessory navicular presents commonly with medial midfoot pain and may require surgical intervention after failure of nonsurgical treatment. Although an accessory navicular can be treated surgically with simple excision, there is some recent evidence that supports concomitant reconstruction of associated flatfoot deformities. Os trigonum, an ossicle posterior to the talus, is also commonly asymptomatic. However, os trigonum may be associated with persistent posterior ankle pain, and open and endoscopic resection techniques are successful. Os subfibulare is an uncommon ossicle that may be associated with recurrent ankle sprains. Recent literature reports successful return to activities after ossicle excision and ligament reconstruction. Os subtibiale may be confused with a medial malleolar fracture in skeletally immature patients. Os peroneum may contribute to lateral midfoot pain.

Foot joint coupling variability differences between habitual rearfoot and forefoot runners prior to and following an exhaustive run

As joint coupling variability has been associated with running-related lower extremity injury, the purpose of this study was to identify how variability within the foot may be different between forefoot (FFS) and rearfoot strike (RFS) runners. Identifying typical variability in uninjured runners may contribute to understanding of ideal coordination associated with running foot strike patterns.Fifteen FFS and 15 RFS runners performed a maximal-effort 5 km treadmill run. A 7-segment foot model identified 6 functional articulations (rearfoot, medial and lateral midfoot and forefoot, and 1st metatarsophalangeal) for analysis. Beginning and end of the run motion capture data were analyzed. Vector coding was used to calculate 6 joint couples. Standard deviations of the coupling angles were used to identify variability within subphases of stance (loading, mid-stance, terminal, and pre-swing). Mixed between-within subjects ANOVAs compared differences between the foot strikes, pre and post run.Increased variability was identified within medial foot coupling for FFS and within lateral foot coupling for RFS during loading and mid-stance. The exhaustive run increased variability during mid-stance for both groups.Interpretation. Joint coupling variability profiles for FFS and RFS runners suggest different foot regions have varying coordination needs which should be considered when comparing the strike patterns.

Classifying sitting, standing, and walking using plantar force data.

Prolonged static weight-bearing at work may increase the risk of developing plantar fasciitis (PF). However, to establish a causal relationship between weight-bearing and PF, a low-cost objective measure of workplace behaviors is needed. This proof-of-concept study assesses the classification accuracy and sensitivity of low-resolution plantar pressure measurements in distinguishing workplace postures. Plantar pressure was measured using an in-shoe measurement system in eight healthy participants while sitting, standing, and walking. Data was resampled to simulate on/off characteristics of 24 plantar force sensitive resistors. The top 10 sensors were evaluated using leave-one-out cross-validation with machine learning algorithms: support vector machines (SVMs), decision tree (DT), discriminant analysis (DA), and k-nearest neighbors (KNN). SVM and DT best classified sitting, standing, and walking. High classification accuracy was obtained with five sensors (98.6% and 99.1% accuracy, respectively) and even a single sensor (98.4% and 98.4%, respectively). The central forefoot and the medial and lateral midfoot were the most important classification sensor locations. On/off plantar pressure measurements in the midfoot and central forefoot can accurately classify workplace postures. These results provide the foundation for a low-cost objective tool to classify and quantify sedentary workplace postures.

Consensus on Indications for Medial Cuneiform Opening Wedge (Cotton) Osteotomy in the Treatment of Progressive Collapsing Foot Deformity.

Forefoot varus is a physical and radiographic examination finding associated with the Progressive Collapsing Foot Deformity (PCFD). Varus position of the forefoot relative to the hindfoot is caused by medial midfoot collapse with apex plantar angulation of the medial column. Some surgeons use the term forefoot supination to describe this same deformity (see Introduction section with nomenclature). Correction of this deformity is important to restore the weightbearing tripod of the foot and help resist a recurrence of foot collapse. When the forefoot varus deformity is isolated to the medial metatarsal and medial cuneiform, correction is indicated with an opening wedge medial cuneiform (Cotton) osteotomy, typically with interposition of an allograft bone wedge from 5 to 11 mm in width at the base. When the forefoot varus is global, involving varus angulation of the entire forefoot and midfoot relative to the hindfoot, other procedures are needed to adequately correct the deformity. Level V, consensus, expert opinion.

An individually moulded insole with 5-mm medial arch support reduces peak impact and loading at the heel after a one-hour treadmill run

BackgroundFoot pain experienced by long-distance runners could be relieved by functional insoles which aim at evenly distributing the plantar pressure. Research questionWe hypothesised that an individually moulded insole with medial arch support would reduce the impact and loading under the heel and metatarsal regions. MethodsTwelve male recreational runners ran on a treadmill at 10 km/h for 1 hour with flat insoles and medial arch supported insoles. A pressure insole system (Novel Pedar, Germany) was used to obtain the peak pressure, peak force, time normalised pressure-time integrals, and the percentage of the total force-time integrals under 10 regions. ResultsMedial arch supported insoles reduced the peak force under the heel (medial: -15.3%, p = 0.001; lateral: -19.2%, p = 0.037) during the initial run, and reduced peak pressure under the heel (medial: -13.3%, p = 0.005; lateral: -9.9%, p = 0.006), and peak force under the medial heel (-17.8%, p = 0.006) after the run. The percentage of the total force-time integrals under the heel was reduced (medial: -23.8%, p = 0.004; lateral: -13.6%, p = 0.022) after the run. No significant difference was found under the metatarsal regions. There is shift of load from the metatarsal regions to the medial mid-foot as indicated by the change of the percentage of total force-time integrals. SignificanceMedial arch supported insoles were effective in reducing the impact and loading under the heel region in prolonged running on a treadmill. Level of evidenceControlled laboratory study, Level V