In Vivo Forces in the Plantar Fascia During the Stance Phase of Gait

Plantar fasciotomies have become commonplace in podiatric and orthopedic medicine for the treatment of plantar fasciitis. However, several complications have been associated with plantar fascial release. It has been speculated that the cause of these complications is excessive release of the plantar fascia. The aim of this project was to determine whether the amount of fascia released, from medial to lateral, causes a significant increase in force in the remaining fascia. A dynamic loading system was developed that allowed a cadaveric specimen to replicate the stance phase of gait. The system was capable of applying appropriate muscle forces to the extrinsic tendons on the foot and replicating the in vivo timing of the muscle activity while applying force to the tibia and fibula from heel strike to toe-off. As the plantar fascia was sequentially released from medial to lateral, from intact to 33% released to 66% released, the real-time force and the duration of force in the remaining fascia increased significantly, and the force was shifted later in propulsion. In addition, the subtalar joint was unable to resupinate as the amount of fascia release increased, indicating a direct relationship between the medial band of the plantar fascia and resupination of the subtalar joint during late midstance and propulsion. (J Am Podiatr Med Assoc 93(6): 429-442, 2003)

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INFLUENCE OF GENDER ON GASTROCNEMIUS MUSCLE ACTIVITY DURING THE STANCE PHASE OF GAIT

Journal of Musculoskeletal Research ◽

10.1142/s021895771250011x ◽

2012 ◽

Vol 15 (02) ◽

pp. 1250011

Author(s):

Thomas A. Abelew ◽

Brian J. Cuda ◽

Jonathan E. Koontz ◽

Julia C. Stell ◽

Marie A. Johanson

Keyword(s):

Muscle Activity ◽

Knee Flexion ◽

Stance Phase ◽

Gastrocnemius Muscle ◽

Heel Strike ◽

Men And Women ◽

Ankle Kinematics ◽

Stance Time ◽

Set Up ◽

Gastrocnemius Muscles

Purpose: Differences in muscle activity have been observed between men and women in numerous lower extremity muscles in a variety of activities. These differences may be related to observed differences in the incidence of injuries between men and women. The purpose of this work is to determine if gender had an effect on the activity of the medial and lateral gastrocnemius muscles during the early part of the stance phase of gait. Method: An observational cohort study was set up using sixteen volunteers (9 men and 7 women, mean age = 27 years) with less than 5° of passive ankle-dorsiflexion range of motion. Maximum dorsiflexion, maximum knee flexion, stance time and EMG magnitude were measured for both men and women during early stance (heel strike to heel off). Results: EMG amplitude of the LG muscle in women was significantly higher than that of men. No significant differences were observed between men and women for maximum dorsiflexion, maximum knee flexion or stance time. Conclusions: A gender difference in gastrocnemius muscle EMG magnitude exists that is independent of knee and ankle kinematics and walking speed.

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Dynamic in Vivo Subtalar Joint Kinematics Measured Using a Skin Marker–Based Protocol

Journal of the American Podiatric Medical Association ◽

10.7547/0003-0538-104.4.357 ◽

2014 ◽

Vol 104 (4) ◽

pp. 357-364 ◽

Cited By ~ 1

Author(s):

Ivan Birch ◽

Kevin Deschamps

Keyword(s):

Subtalar Joint ◽

Stance Phase ◽

Face Validity ◽

Exclusion Criteria ◽

In Vivo Kinematics ◽

Skin Marker ◽

The Face ◽

And Function ◽

Interpatient Variation

Background The subtalar joint allows complex motion of the foot relative to the leg, the analysis of which has presented a major challenge for researchers. The considerable interpatient variation in structure and function of the subtalar joint highlights the importance of developing a protocol to assess the kinematics in individuals rather than developing an overarching description of function. The use of skin-mounted markers is, therefore, preferable, allowing the noninvasive collection of data. We sought to assess the face validity of a skin-mounted marker–based protocol to measure the in vivo kinematics of the subtalar joint. Methods Thirty participants were recruited using minimal exclusion criteria. A previously tested skin-mounted marker placement protocol was used in conjunction with two CODA MPX 30 sensors to capture data during walking. The data produced were compared with those from previous studies that used bone-mounted markers. Results The results in all three planes represented feasible outcomes compared with those of previous studies, the data falling within the ranges published. Patterns of movement demonstrated are similar to, although not the same as, those shown by previous investigations. Conclusions This study did not produce patterns of movement that exactly matched those of previous investigations. The results were, however, within the ranges previously published, and the patterns of movement shown were feasible. The results suggest the face validity of the method as a means of assessing the in vivo kinematics of the subtalar joint during the stance phase of gait.

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Design and validation of a foot–ankle dynamic simulator with a 6-degree-of-freedom parallel mechanism

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411920938902 ◽

2020 ◽

Vol 234 (10) ◽

pp. 1070-1082

Author(s):

Dongmei Wang ◽

Wei Wang ◽

Qinyang Guo ◽

Guanglin Shi ◽

Genrui Zhu ◽

...

Keyword(s):

Parallel Mechanism ◽

Stance Phase ◽

The Body ◽

Degree Of Freedom ◽

External Control ◽

Foot And Ankle ◽

Multiple Correlation ◽

Cadaveric Specimen ◽

Dynamic Simulator

An in vitro simulation test using a designed well-targeted test rig has been regarded as an effective way to understand the kinematics and dynamics of the foot and ankle complex in the dynamic stance phase, and it also allows alterations in both internal and external control compared to in vivo tests. However, current simulators are limited by some assumptions. In this study, a novel foot and ankle bionic dynamic simulator was developed and validated. A movable 6-degree-of-freedom parallel mechanism, known as Steward platform, was used as the core structure to drive the tibia, with a tibial force actuator applied with different loads. Four major muscle groups were actuated by four sensored pulling cables connected to muscle tendons. Simulation processes were controlled using a software developed based on a proportional–integral–derivative control loop, with tension–compression sensors mounted on tendon pulling cables and used as real-time monitor signals. An iterative learning module for tibial force control was integrated into the control software. Six specimens of the cadaveric foot–ankle were used to validate the simulator. The stance phase was successfully simulated within 5 s, and the tibia loads were applied based on the body weight of the cadaveric specimen donors. Typical three-dimensional ground reaction forces were successfully reproduced. The coefficient of multiple correlation analysis demonstrated good repeatability of the dynamic simulator for the ground reaction force (coefficient of multiple correlation > 0.89) and the range of ankle motion (coefficient of multiple correlation > 0.87 with only one exception). The simulated ranges of the foot–ankle joint rotation in stance were consistent with in vivo measurements, indicating the success of the dynamic simulation process. The proposed dynamic simulator can enhance the understanding of the mechanism of the foot–ankle movement, related injury prevention, and surgical intervention.

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The Effect of Excessive Subtalar Inversion/Eversion on the Dynamic Function of the Soleus and Gastrocnemius During the Stance Phase

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-206242 ◽

2009 ◽

Author(s):

Ruoli Wang ◽

Elena M. Gutierrez-Farewik

Keyword(s):

Subtalar Joint ◽

Stance Phase ◽

Heel Strike ◽

Neutral Position ◽

Plantar Flexor ◽

Normal Gait ◽

Joint Axis ◽

Dynamic Function ◽

Foot Pronation ◽

Pathological Gait

Gastrocnemius and soleus are often considered as ankle plantarflexors. Their dynamic functions in normal and pathological gait have been well-studied. However, in a neutral position, the tendon passes medial to the subtalar joint axis and therefore produces an inversion moment in addition to the plantar-flexor moment [1]. It was believed that gastrocnemius and soleus are the major dynamic stabilizers preventing excess foot pronation. During normal gait, the subtalar joint experiences rapid eversion following heel strike and subsequent inversion during terminal stance [2]. Varus and valgus foot positions caused by excessive subtalar inversion/eversion can be found in spastic and flaccid paralysis [3]. Although it is widely understood that muscle forces can have important local and remote effects on joints and segments [4], the interrelations between dynamic gastrocnemius and soleus functions and excessive subtalar inversion/eversion remain unclear.

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Local Bone Deformation at Two Predominant Sites for Stress Fractures of the Tibia: An In Vivo Study

Foot & Ankle International ◽

10.1177/107110079801900711 ◽

1998 ◽

Vol 19 (7) ◽

pp. 479-484 ◽

Cited By ~ 32

Author(s):

Ingrid Ekenman ◽

Kjartan Halvorsen ◽

Pär Westblad ◽

Li Fellãnder-Tsai ◽

Christer Rolf

Keyword(s):

Stance Phase ◽

Distal Tibia ◽

Force Plate ◽

Stress Fractures ◽

Heel Strike ◽

Local Bone ◽

Healthy Female ◽

Reaction Forces

Local bone deformation was registered at two predominant injury sites for tibial stress fractures in a healthy female volunteer. Two instrumented strain gauge staples were inserted under local anesthesia to the anterior middiaphysis (AM) and to the posteromedial part of the distal tibia (PD). Calibration and reliability of the instrumented staple system have previously been demonstrated in vitro. Concomitant ground reaction forces were registered with a Kistler force plate. Studying peak values, it was shown that during a voluntary 30-cm forward jump, PD deformation was greater during forefoot landing (2700–4200 microstrain) than during a heel strike landing (1200–1900 microstrain) and also compared with the concomitant AM deformation under both above testing conditions (1300–1900 microstrain). The stance phase during walking resulted in PD deformation of 950 microstrain, whereas the concomitant AM deformation was 334 microstrain. The greatest AM deformation (mean, 2128 microstrain) was registered during ground contact after a voluntary vertical drop from a height of 45 cm, concomitant with a PD deformation of 436 microstrain. These data are the first to show different local deformations at various sites of the tibia in vivo. The PD deformation was larger than previously noted from other parts of the tibia, whereas the middiaphysis data are consistent with other reports. The results may support the clinical assumption of different etiologies for stress fractures at these predominant sites.

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Relationship Between Neutral Subtalar Joint Position and Pattern of Rearfoot Motion During Walking

Foot & Ankle International ◽

10.1177/107110079401500309 ◽

1994 ◽

Vol 15 (3) ◽

pp. 141-145 ◽

Cited By ~ 75

Author(s):

Thomas McPoil ◽

Mark W. Cornwall

Keyword(s):

Subtalar Joint ◽

Stance Phase ◽

Heel Strike ◽

Neutral Position ◽

Typical Pattern ◽

Healthy Young Adult ◽

Phase Duration ◽

Foot Posture ◽

Rearfoot Motion ◽

The Relationship

The purpose of this study was to determine the relationship between the angle formed by the rearfoot when the subtalar joint is positioned in neutral and the pattern of rearfoot motion during walking. Each lower extremity for 50 healthy young adult subjects (mean age 25.5 years) was videotaped and the pattern of rearfoot motion was assessed using two-dimensional analysis. The results indicate that the rearfoot is slightly inverted before heel strike and that the average time to maximum pronation occurs at approximately 37.9% of the stance phase duration. Contrary to a previously published theory, the “neutral” position of the rearfoot for the typical pattern of rearfoot motion during the walking cycle was found to be resting standing foot posture rather than subtalar joint neutral position.

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Biomechanical Aspects of the Static and Dynamic Patterns of the Feet of Runners with Plantar Fasciitis and Their Relationship with Sports Shoes

10.5772/intechopen.97090 ◽

2021 ◽

Author(s):

Ana Paula Ribeiro

Keyword(s):

Literature Review ◽

Plantar Fasciitis ◽

Subtalar Joint ◽

Chronic Phase ◽

Plantar Fascia ◽

Heel Pain ◽

Foot Biomechanics ◽

Clinical Support ◽

The Stability ◽

Sports Shoes

The purpose of this literature review was to evaluate studies that have investigated static and dynamic biomechanical patterns of the feet in runners with plantar fasciitis, as well as their relationship with sports shoes and insoles prescription. Original articles with different design on this theme were considered. In general, the increase plantar load rates in runners with plantar fasciitis may be directly related to changes in the plantar arch (elevated) and the rearfoot alignment in pronation, as well as the effect of shoes or insoles to reduce heel pain. In summary, the clinical support of the literature review was showed that a decrease in the medial longitudinal arch induces greater mobility of the foot, which promotes a greater angle of rearfoot pronation to maintain the stability of the subtalar joint during static and dynamic feet support in activities, such as running. This results in a greater overload on the medial region of the calcaneus, producing greater stress on the plantar fascia, contributing to the development and progression of plantar fasciitis in runners. In addition, treatment of acute plantar fasciitis was associate to insoles while chronic phase associated for shoes ultra-flexible intermediate midsole for heel pain reduction and improvement foot biomechanics in runners with plantar fasciitis.

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Movement Coupling at the Ankle During the Stance Phase of Running

Foot & Ankle International ◽

10.1177/107110070002100309 ◽

2000 ◽

Vol 21 (3) ◽

pp. 232-239 ◽

Cited By ~ 32

Author(s):

Alex Stacoff ◽

Benno M. Nigg ◽

Christoph Reinschmidt ◽

Anton J. van den Bogert ◽

Arne Lundberg ◽

...

Keyword(s):

Stance Phase ◽

Three Dimensional ◽

Heel Strike ◽

Second Phase ◽

Healthy Male ◽

Bone Level ◽

Joint Coordinate System ◽

Male Subjects

The purpose of this study was to quantify movement coupling at the ankle during the stance phase of running using bone-mounted markers. Intracortical bone pins with reflective marker triads were inserted under standard local anaesthesia into the calcaneus and the tibia of five healthy male subjects. The three-dimensional rotations were determined using a joint coordinate system approach. Movement coupling was observed in all test subjects and occurred in phases with considerable individual differences. Between the shoe and the calcaneus coupling increased after midstance which suggested that the test shoes provided more coupling for inversion than for eversion. Movement coupling between calcaneus and tibia was higher in the first phase (from heel strike to midstance) compared with the second phase (from midstance to take-off). This finding is in contrast to previous in-vitro studies but may be explained by the higher vertical loads of the present in-vivo study. Thus, movement coupling measured at the bone level changed throughout the stance phase of running and was found to be far more complex than a simple mitered joint or universal joint model.

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