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The plantar aponeurosis comprises medial, central, and lateral bands, which arise from the calcaneal tuberosity. Descriptions of the origin of the abductor hallucis vary among different textbooks. The central band and abductor hallucis muscles are related to the windlass mechanism. Given the uncertainties regarding the details of the origins of the central band and the abductor hallucis muscle, we examined those origins in 100 feet of 50 cadavers (25 males and 25 females) by dissection. There were three central band patterns, depending on the attachment sites of the origins of the central and lateral bands: Pattern Ia, the central band covers the lateral band completely; Pattern Ib, the central band covers part of the lateral band; Pattern II, the lateral band covers part of the central band. The origin of the abductor hallucis muscle was confirmed. It showed two types of variation: attachment type, originating from the central band; non-attachment type, not originating from the central band. Central band Patterns Ia, Ib, and II were found in 23 feet (17 males, 6 females), 24 feet (25 males, 28 females), and 24 feet (eight males, 16 females), respectively. Pattern Ia predominated in males and Pattern II in females. The attachment and non-attachment types of abductor hallucis muscle were observed in 28 feet (28%) and 72 feet (72%), respectively. The attachment type with Patterns Ia, Ib, and II was shown in 17 feet, 10 feet, and one foot, respectively. Thus, we revealed variation and sex differences in the central band, which could affect foot morphology and the efficacy of the windlass mechanism.
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BACKGROUND: The surgical treatment of hallux valgus (HV) deformity has been the subject of countless publications but few focus on the altered windlass mechanism or analyze the biomechanical behavior immediately after surgery. METHODS: Patients treated for HV between January and March 2023 were included. The surgery consisted of a L-reverse first metatarsal osteotomy. To analyze the windlass mechanism we record two different measurements; the isolated first metatarsophalangeal joint (MTPJ) dorsiflexion angle (IDA) and dynamic plantarization of the first metatarsal head when performing first MTPJ dorsiflexion imprinting a mark on a modeling foam. RESULTS: A total of 30 patients diagnosed with symptomatic HV were included. In all patients, a change in the IDA angle was evident, being overall statistically significant. About modeling foam imprinted mark, all measurements, in all planes of space, had a clear tendency to increase, which turned out to be statistically significant (p < 0.001). CONCLUSIONS: An altered windlass mechanism may be successfully recovered immediately after hallux valgus deformity surgery. This could be evinced by an indirect measurement analyzing the imprint of the head of the first metatarsal in a modeling foam and the IDA. LEVELS OF EVIDENCE II: None.
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Hallux Valgus , Ossos do Metatarso , Osteotomia , Hallux Valgus/cirurgia , Hallux Valgus/fisiopatologia , Humanos , Osteotomia/métodos , Masculino , Fenômenos Biomecânicos , Feminino , Pessoa de Meia-Idade , Ossos do Metatarso/cirurgia , Articulação Metatarsofalângica/cirurgia , Articulação Metatarsofalângica/fisiopatologia , Adulto , IdosoRESUMO
[Purpose] This study aimed to calculate the windlass mechanism in one walking cycle (WC) using the medial longitudinal arch (MLA) height and compare its mechanism with joint moments, angles, and center of gravity movement. [Participants and Methods] The study analyzed the gait of 20 healthy adults (14 males, six females) using a three-dimensional motion analyzer to calculate several parameters. [Results] In the terminal stance, the MLA height reached 20.6 ± 6.0â mm (minimum value) at 49% WC. Simultaneously, the ankle dorsiflexion angle, ankle internal plantarflexion moment, and forward shift of the center of gravity reached the maximum values. At 62% WC, the MLA height was 26.8 ± 4.8â mm and reached maximum during the stance phase, indicating a windlass mechanism. Additionally, the MLA height was 61.7 ± 22.7â mm at 69% WC, indicating an MLA spiking phenomenon. [Conclusion] The MLA height was lowest at 49% WC due to reverse windlass mechanism. Although the windlass mechanism was activated at 62% WC, it was functionally equivalent to the swing phase. Push-off was impossible during the swing phase. At 69% WC, the swing phase showed a second windlass mechanism.
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BACKGROUND: Civilians are often first-line responders in hemorrhage control; however, windlass tourniquets are not intuitive. Untrained users reading enclosed instructions failed in 38.2% of tourniquet applications. This prospective follow-up study replicated testing following Stop the Bleed (STB) training. MATERIALS AND METHODS: One and six months following STB, first-year medical students were randomly assigned a windlass tourniquet with enclosed instructions. Each was given one minute to read instructions and two minutes to apply the windlass tourniquet on the TraumaFX HEMO trainer. Demographics, time to read instructions and stop bleeding, blood loss, and simulation success were analyzed. RESULTS: 100 students received STB training. 31 and 34 students completed tourniquet testing at one month and six months, respectively. At both intervals, 38% of students were unable to control hemorrhage (P = 0.97). When compared to the pilot study without STB training (median 48 sec, IQR 33-60 sec), the time taken to read the instructions was shorter one month following STB (P <0.001), but there was no difference at 6 months (P = 0.1). Incorrect placement was noted for 19.4% and 23.5% of attempts at 1 and 6 months. Male participants were more successful in effective placement at one month (93.3% versus 31.3%, P = 0.004) and at six months (77.8% versus 43.8%, p = 0.04). CONCLUSIONS: Skills decay for tourniquet application was observed between 1 and 6 months following STB. Instruction review and STB produced the same hemorrhage control rates as reading enclosed instructions without prior training. Training efforts must continue; but an intuitive tourniquet relying less on mechanical advantage is needed.
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Hemorragia , Torniquetes , Seguimentos , Hemorragia/etiologia , Hemorragia/terapia , Humanos , Masculino , Projetos Piloto , Estudos ProspectivosRESUMO
The arch of the human foot is unique among hominins as it is compliant at ground contact but sufficiently stiff to enable push-off. These behaviours are partly facilitated by the ligamentous plantar fascia whose role is central to two mechanisms. The ideal windlass mechanism assumes that the plantar fascia has a nearly constant length to directly couple toe dorsiflexion with a change in arch shape. However, the plantar fascia also stretches and then shortens throughout gait as the arch-spring stores and releases elastic energy. We aimed to understand how the extensible plantar fascia could behave as an ideal windlass when it has been shown to strain throughout gait, potentially compromising the one-to-one coupling between toe arc length and arch length. We measured foot bone motion and plantar fascia elongation using high-speed X-ray during running. We discovered that toe plantarflexion delays plantar fascia stretching at foot strike, which probably modifies the distribution of the load through other arch tissues. Through a pure windlass effect in propulsion, a quasi-isometric plantar fascia's shortening is delayed to later in stance. The plantar fascia then shortens concurrently to the windlass mechanism, likely enhancing arch recoil at push-off.
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Fáscia , Corrida , Fenômenos Biomecânicos , Pé , Marcha , HumanosRESUMO
During traditional fusion procedures surgeons initially perform a joint resection and then the structures are realigned for correction of deformity. The procedure described herein by the author reverses this traditional surgical approach by first realigning the joint to correct deformity, then after achieving a corrected alignment, joint resection is performed in parallel without wedging. Realigning deformity as an initial step creates the conditions for an in-situ fusion wherein the deformity is corrected simultaneously with parallel bone resection. The purpose of this paper is to review the advantages and technical aspects of a realignment arthrodesis technique in which joint resection begins with the foot in the corrected position. This approach to joint fusion has been shown to simplify bone resection, eliminate post-resection adjustments, create full apposition of fusion surfaces, reliably correct deformity, and result in solid arthrodesis. The technique provides for immediate correction of deformity and is amenable for conditions that require either minimal or significant segmental shortening. There are many areas where the "Realign-resect" approach to joint fusion would be well suited. Full implementation of this technique may be particularly useful to the surgeon who does not have seasoned assistants in the operating room.
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Artrodese , Pé , Pé/cirurgia , HumanosRESUMO
Surgical repair of complete plantar fascia ruptures has not yet been reported in the literature. Operative technique and outcome are described in 2 gymnasts with heavy plyometric demands who received surgical repair compared with 3 athletes treated nonoperatively. Biomechanics and clinical implications are discussed. In the last 8 years, we have seen 5 high-demand athletes with total rupture of the plantar fascia. This is a retrospective clinical evaluation 1.5 to 8 years postinjury of all 5 patients using dynamic ultrasound, Foot Function Index, sports-specific questions, Foot Posture Index, and foot length. The operated gymnasts returned to the same level of performance within 12 months. None of the conservatively treated athletes returned to preinjury plyometric sports levels but reached a foot load capacity of distance running with the injured foot as limiting factor. Ultrasound with simultaneous dorsiflexion of the toes showed a normal fascia in the operated patients, but a slack fascia that tightened up only at terminal toe dorsiflexion in the conservatively treated group. According to the Foot Function Index, the operated patients reported no complaints, whereas the nonoperative group had clinical relevant impairments in activities of daily life. The Foot Posture Index in all nonoperated patients showed a relative shift toward pronation with increased foot length compared with the noninjured foot. The operated patients showed no difference in foot length but minimal shift into supination with a slightly altered arch contour. Surgical repair of plantar fascia ruptures is technically feasible to restore normal foot load capability with return to high-demand plyometric sports within 12 months.
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Traumatismos em Atletas/cirurgia , Fáscia/lesões , Traumatismos do Pé/cirurgia , Pé/cirurgia , Antepé Humano/lesões , Antepé Humano/cirurgia , Adulto , Feminino , Traumatismos do Pé/etiologia , Humanos , Masculino , Ruptura , Adulto JovemRESUMO
BACKGROUND: The truss/windlass coefficients ware reported as a surrogate parameter for foot stiffness while walking. However, the construct validity and reliability of whether the truss/windlass coefficients reflect foot stiffness have not been sufficiently validated. This study validated the truss/windlass coefficient reflects the construct validity and reliability of foot stiffness. METHODS: Participants were 25 healthy young males (21.6 ± 0.7 years). Foot stiffness was assessed using Simplified Foot Stiffness. It was determined by dividing the difference in foot load between sitting and standing by the rate of change in navicular height. The truss/windlass coefficient was calculated as the behavior of the foot arch during middle to late stance. To assess the reliability of each parameter, intraclass correlation coefficients (ICC 1.1) and Bland-Altman analysis were used, and Spearman's rank correlation coefficients were used to determine construct validity. RESULTS: The truss coefficient (ICC1.1 0.86) and Simplified Foot Stiffness (ICC1.1 0.87) demonstrated high reliability and no systematic error. However, the windlass coefficient (ICC1.1 0.73) demonstrated moderate reliability and proportional error. Furthermore, the truss coefficient had a significant positive correlation with Simplified Foot Stiffness (r = 0.504; p < 0.01), whereas the windlass coefficient did not (r = 0.06; p = 0.67). CONCLUSION: The truss coefficient was proposed as a highly reliable parameter that reflects foot stiffness. However, the windlass coefficient has a proportional error, despite being moderately reliable.
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Pé , Caminhada , Humanos , Masculino , Nível de Saúde , Extremidade Inferior , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Plantar fasciitis is stated to arise because of inadequate accumulated tension at the plantar fascia's enthesis. Tensile load and prolonged strain cause tiny rips in the fascia, which trigger a chronic inflammation process of healing. This case report shows the diagnostic evaluations, assessment of the condition, and physical rehabilitation management for a 45-year-old female nurse working in the neurosurgical critical care unit who had been experiencing plantar medial and posterior heel pain, as well as discomfort at the calcaneal tuberosity, for the previous six months. To increase functional mobility and alleviate symptoms, the patient sought out physiotherapy intervention. In this case, a physiotherapeutic program was implemented to treat plantar fasciitis, enhance mobility, and encourage long-term recovery. The evaluation included a detailed review of the patient's gait, biomechanics, and circumstances that may have contributed to the ongoing problems. The multimodal strategy used in the intervention plan included manual therapy, strengthening and stretching exercises, as well as patient education and counselling on self-management techniques. The patient's functional mobility increased along with a steady reduction in discomfort during the duration of the physiotherapy sessions. The instance emphasises how important it is to manage persistent plantar fasciitis with a customised physical therapy strategy that takes the patient's specific requirements into account and addresses contributory variables. The present study adds to the extant literature on efficacious physiotherapeutic approaches for plantar fasciitis, highlighting the need for a holistic approach in attaining favourable results for individuals enduring heel discomfort.
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BACKGROUND: In patients with rheumatoid arthritis (RA), the pathological progression of lower limb biomechanics is established. Although specific aspects of RA gait patterns have been studied and described, we are aware of no studies of gait pattern compensations over the entire disease course. This study aimed to describe a model that could predict the evolution of lower limb pathomechanics in patients with RA. METHODS: A literature review was conducted of electronic databases (MEDLINE, PEDro, Trip Database, DOAJ, BioMed Central, PLOS clinical trial, ScienceDirect, and CRD York University, AHRQ, NICE, Cochrane Library) to October 3, 2023. RESULTS: A theory was developed that all people with RA induce or augment gait evolution syndromes following the same biomechanical course. Specifically, we postulate the "rheumatoid equinus syndrome," the "rheumatoid abnormal pronation syndrome" and the "rheumatoid shuffle syndrome," which have never been described before. CONCLUSIONS: A new model of the evolution of gait compensation in RA is proposed. An important challenge of RA is that it increases the risk of ulcerative lesions, falls, pain, fractures, and healthcare costs. The proposed model can be used to reduce morbidity in this patient group by helping to explain and reduce the pain, deformity, and ankylosis of foot RA.
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BACKGROUND: The windlass mechanism (WM) increases the longitudinal arch of the foot via tension of the plantar aponeurosis during dorsiflexion of the metatarsophalangeal (MTP) joint. The purpose of this study was to perform a 3-dimensional evaluation of the displacement of each joint and the height of the navicular during dorsiflexion of the first MTP joint by using weightbearing computed tomography (CT). METHODS: Participants were 6 men and 8 women with 23 healthy feet. CT of the foot with a load equivalent to the participant's body weight was performed. The first MTP joint was in the neutral position and dorsiflexed 30 degrees. Between the conditions, we measured the (1) rotation of each bone, (2) rotation of the distal bone with respect to the proximal bone at each joint, and (3) height of the navicular. RESULTS: With respect to the tibia, the calcaneus was at 0.8 ± 0.7 degrees dorsiflexion and 1.4 ± 0.9 degrees inversion, while the talus was at 2.0 ± 1.2 degrees dorsiflexion and 0.1 ± 0.8 degrees eversion. The navicular was at 1.3 ± 1.2 degrees dorsiflexion and 3.2 ± 2.1 degrees inversion, whereas the medial cuneiform was at 0.3 ± 0.6 degrees plantarflexion and 1.3 ± 1.1 degrees inversion. At the talonavicular joint, the navicular was at 0.7 ± 1.3 degrees plantarflexion, whereas at the cuneonavicular joint, the medial cuneiform bone was at 1.4 ± 1.4 degrees plantarflexion. The height of the navicular increased by 1.1 ± 0.6 mm. CONCLUSION: We 3-dimensionally confirmed the dynamics of WM and found that the calcaneus, navicular, and medial cuneiform moved in all 3 planes. The results suggest that the cuneonavicular joint has the greatest movement among the joints. We believe that these findings will help to elucidate the pathogenesis of WM-related diseases and lead to advances in treatments for pathologies involving the longitudinal arch. LEVEL OF EVIDENCE: Level IV, case series.
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Imageamento Tridimensional , Tálus , Masculino , Humanos , Feminino , Voluntários Saudáveis , Tomografia Computadorizada por Raios X/métodos , Suporte de Carga , Fenômenos BiomecânicosRESUMO
This paper presents the design and testing of an arched foot with several biomimetic features, including five individual MTP (toe) joints, four individual midfoot joints, and plantar fascia. The creation of a triple-arched foot represents a step further in bio-inspired design compared to other published designs. The arched structure creates flexibility that is similar to human feet with a vertical deflection of up to 12 mm. The individual toe joints enable abduction-adduction in the forefoot and therefore a natural pronation motion. Adult female bone data was obtained and converted into a CAD model to accurately identify the location of bones, joints, and arches. An analytical model is presented that gives the relationship between the vertical stiffness and horizontal stiffness of the longitudinal arches and therefore allows the optimization of stiffness elements. Experimental tests have demonstrated a vertical arch stiffness of 76 N/mm which is similar to adult human feet. The range of movement of the foot is similar to human feet with the following values: dorsi-plantarflexion (28°/37°), inversion-eversion (30°/15°), and abduction-adduction (30°/39°). Tests have also demonstrated a three-point contact with the ground that is similar to human feet.
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AIMS: This study aimed to quantify the degrees of movement that occur in the lower limb using a kinematic system after taking two measurements of 45° and 60° of extension at the first metatarsophalangeal joint (1st MTPJ) and to test the validity of this sensor system using radiography. METHODOLOGY: This was a quasi-experimental test-post-test study with a single intervention group (25 subjects). Four inertial sensors were placed on the proximal phalange of the first toe, dorsum of the foot, medial-lateral of the leg (level of tibia), and medial-lateral of the thigh (level of femur). The extension of the 1st MTPJ produced movements of supination in the foot and rotation at the level of leg and thigh. We studied this mechanism in three situations (relaxed, 45°, and 60°) both with the sensors and with X-rays. RESULTS: With the kinematic system, there was an increase in the range of movement in each of the variables, with a value of p < 0.05. The relationship between the kinematic system and the radiography was tested using Spearman's rho test, obtaining a correlation coefficient of 0.624 and a value of p < 0.05, and the Bland-Altman graph, with 90% of the cases within the tolerance limits. CONCLUSIONS: The extension of the 1st MTPJ generated kinematic changes associated with supination movement in the midfoot and external rotation on the tibia and femur level. Both measurement techniques were very similar in the way that they quantified the degrees of extension of the 1st MTPJ. If we extrapolate this result to the measurement technique used by the inertial sensors, we could affirm that the values recorded in the supination and external rotation movements were reliable.
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Extremidade Inferior , Tíbia , Humanos , Amplitude de Movimento Articular , Fêmur , MovimentoRESUMO
BACKGROUND: Hemorrhage control prior to shock onset is increasingly recognized as a time-critical intervention. Although tourniquets (TQs) have been demonstrated to save lives, less is known about the physiologic parameters underlying successful TQ application beyond palpation of distal pulses. The current study directly visualized distal arterial occlusion via ultrasonography and measured associated pressure and contact force. METHODS: Fifteen tactical officers participated as live models for the study. Arterial occlusion was performed using a standard adult blood pressure (BP) cuff and a Combat Application Tourniquet Generation 7 (CAT7) TQ, applied sequentially to the left mid-bicep. Arterial flow cessation was determined by radial artery palpation and brachial artery pulsed wave doppler ultrasound (US) evaluation. Steady state maximal generated force was measured using a thin-film force sensor. RESULTS: The mean (95% CI) systolic blood pressure (SBP) required to occlude palpable distal pulse was 112.9mmHg (109-117); contact force was 23.8N [Newton] (22.0-25.6). Arterial flow was visible via US in 100% of subjects despite lack of palpable pulse. The mean (95% CI) SBP and contact force to eliminate US flow were 132mmHg (127-137) and 27.7N (25.1-30.3). The mean (95% CI) number of windlass turns to eliminate a palpable pulse was 1.3 (1.0-1.6) while 1.6 (1.2-1.9) turns were required to eliminate US flow. CONCLUSIONS: Loss of distal radial pulse does not indicate lack of arterial flow distal to upper extremity TQ. On average, an additional one-quarter windlass turn was required to eliminate distal flow. Blood pressure and force measurements derived in this study may provide data to guide future TQ designs and inexpensive, physiologically accurate TQ training models.
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Extremidades , Torniquetes , Adulto , Humanos , Desenho de Equipamento , Hemorragia , UltrassonografiaRESUMO
BACKGROUND: The foot arch plays an important role in propulsion and shock absorption during walking and running; however, the relationship among the foot arch, metatarsal locking theory, and nature of the windlass mechanism (WM) remain unclear. RESEARCH QUESTION: What are the differences in the kinematic relationship between the foot arch, hindfoot, and hallux during walking and running? METHODS: Relative angles within the foot were measured in 18 healthy men using the Oxford foot model (OFM). Data for barefoot walking at a comfortable speed and rearfoot running at 2.0 m/s were collected. Angles of the forefoot relative to the hindfoot (OFM-arch), hallux relative to the forefoot (Hallux) on the sagittal plane, and hindfoot relative to the shank (Hindfoot) on three anatomical planes were obtained. The medial longitudinal arch (MLA) angle was calculated to verify that OFM-arch can substitute the MLA angle. Each parameter was subjected to cross-correlation analysis and Wilcoxon signed-rank tests to examine the relationship with OFM-arch and compare them during walking and running. RESULT: OFM-arch was similar to the conventional MLA projection angle in both trials (gait: 0.79, running: 0.96 p < 0.01). Synchronization of the OFM-arch and Hallux angles was higher in running than in walking (gait: -0.09, running: -0.75 p < 0.01). Hindfoot supination was unrelated to OFM-arch. Hindfoot angle on the transverse plane exhibited a moderate relationship with OFM-arch, indicating different correlations in walking and running (gait: 0.63, running: -0.68 p < 0.01). SIGNIFICANCE: The elevation of the foot arch due to hallux dorsiflexion differed during walking and running; hence, other factors besides WM (such as intrinsic muscles) may affect the foot arch elevation during running. The hindfoot in the frontal plane does not contribute to arch raising and foot stability during running; it features different relationships with OFM-arch during walking and running.
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Hallux , Corrida , Fenômenos Biomecânicos/fisiologia , Pé/fisiologia , Marcha/fisiologia , Humanos , Masculino , Caminhada/fisiologiaRESUMO
The foot contributes to propulsion and postural stability function by changing its morphology during walking through the truss/windlass mechanisms. We quantified the truss mechanism regarding foot stiffness and the windlass mechanism regarding the movement coordination between the foot arch and metatarsophalangeal (MTP) joint. We aimed to clarify the relationship of these mechanisms with propulsive force and static foot alignment. Forty-eight healthy young adults participated and walked at a comfortable speed. The ground reaction force (GRF), ankle power, and sagittal plane motion of the foot arch and MTP joint were recorded using a three-dimensional motion analysis system. The vertical GRF and foot arch motion were used to quantify foot stiffness as the truss coefficient, and the foot arch and first MTP joint were used to quantify movement coordination as the windlass coefficient. The Foot Posture Index (FPI) and arch height index (AHI) were used to assess static foot alignment. A canonical correlation analysis was performed using the foot- and gait-related index group, and then a single-correlation analysis was performed. The canonical correlation analysis showed that a composite variable consisting of FPI, AHI, and the truss coefficient was related to the anterior GRF (A-GRF) and ankle power. The truss coefficient was positively correlated with A-GRF and ankle power, whereas the windlass coefficient was positively correlated with ankle power. Therefore, the truss and windlass coefficients can be used as indices to evaluate foot function, suggesting that maintaining foot stiffness and foot arch coordination with the first MTP joint is important for propulsion.
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Pé , Marcha , Articulação do Tornozelo , Fenômenos Biomecânicos , Humanos , Caminhada , Adulto JovemRESUMO
Recently, carbon fiber plates, or orthoses, have been incorporated into footwear to improve running performance, presumably through improved energy storage and return. However, few studies have explored the energetic effects these orthoses have on the distal foot, have utilized such orthoses in walking, and none have sought to specifically harness metatarsophalangeal joint deformation to store and return energy to the ankle-foot complex. To address these gaps, we developed and tested a deformable carbon fiber foot orthosis aiming to harness foot energetics and quantify the resulting effects on ankle energetics during walking in healthy adults. Eight subjects walked under three conditions: barefoot (BF), with minimalist shoes (SH), and with bilateral, deformable foot orthoses in the minimalist shoes (ORTH). Ankle and distal foot energetics, foot-to-floor and ankle angle, stance time, step length, and max center of pressure (COP) position were calculated. When walking with the orthoses, subjects showed 263.6% increase in positive distal foot work along with a 31.9% decrease in ankle work and little to no change in the overall ankle-foot complex work. Step length, stance time, and max anterior COP position significantly increased with orthosis use. No statistical or visual differences were found between BF and SH conditions indicating that our findings were due to the foot orthoses. These results suggest this foot orthosis redistributes power from the ankle to the distal foot for healthy adults, reducing the energetic demand on the ankle. These results lay the foundation for designing orthotics and footwear to improve ankle-foot energetics for clinical populations.
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Órtoses do Pé , Adulto , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Marcha , Humanos , CaminhadaRESUMO
The rigidity of the human foot is often described as a feature of our evolution for upright walking and is bolstered by a thick plantar aponeurosis that connects the heel to the toes. Previous descriptions of human foot function consider stretch of the plantar aponeurosis via toe extension (windlass mechanism) to stiffen the foot as it is levered against the ground for push-off during walking. In this study, we applied controlled loading to human feet in vivo, and studied foot function during the push-off phase of walking, with the aim of carefully testing how the foot is tensioned during contact with the ground. Both experimental paradigms revealed that plantar aponeurosis strain via the 'windlass mechanism' could not explain the tensioning and stiffening of the foot that is observed with increased foot-ground contact forces and push-off effort. Instead, electromyographic recordings suggested that active contractions of ankle plantar flexors provide the source of tension in the plantar aponeurosis. Furthermore, plantar intrinsic foot muscles were also contributing to the developed tension along the plantar aspect of the foot. We conclude that active muscular contraction, not the passive windlass mechanism, is the foot's primary source of rigidity for push-off against the ground during bipedal walking.
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Pé , Caminhada , Articulação do Tornozelo , Fenômenos Biomecânicos , Marcha , Humanos , Contração Muscular , Músculo EsqueléticoRESUMO
Understanding of medial column biomechanics is paramount to a successful outcome in both conservative and surgical treatment. Dysfunctions of the dynamic stabilizers as well as the static stabilizers of the medial column play a role in pathomechanics. Conservative options for addressing the medial column include custom foot orthotics and bracing. Options for addressing the medial column surgically with the goal to restore a stable tripod configuration, include first tarsometatarsal joint arthrodesis, opening plantarflexory medial cuneiform osteotomy, and naviculocuneiform arthrodesis.
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Artrodese , Pé Chato/cirurgia , Órtoses do Pé , Osteotomia , Pé Chato/diagnóstico por imagem , Pé Chato/fisiopatologia , Articulações do Pé/cirurgia , Humanos , Ossos do Tarso/cirurgiaRESUMO
Level of Evidence: Level V, expert opinion.