Temporal Influences of Functional Knee Bracing on Torque Production of the Lower Extremity

2006 ◽  
Vol 15 (3) ◽  
pp. 215-227
Author(s):  
Brian Campbell ◽  
James Yaggie ◽  
Daniel Cipriani
Keyword(s):  
Lower Extremity ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Exercise Intervention ◽  
Three Dimensional ◽  
Exercise Program ◽  
Joint Moments ◽  
Repeated Measures Design ◽  
Reaction Forces ◽  
Vertical Ground Reaction Forces

Context:Functional knee braces (FKB) are used prophylactically and in rehabilitation to aide in the functional stability of the knee.Objective:To determine if alterations in select lower extremity moments persist throughout a one hour period in healthy individuals.Design:2X5 repeated measures design.Setting:Biomechanics Laboratory.Subjects:Twenty subjects (14 male and 6 female, mean age 26.5±7 yrs; height 172.4±13 cm; weight 78.6±9 kg), separated into braced (B) and no brace (NB) groups.Intervention:A one-hour exercise program divided into three 20 minute increments.Main Outcome Measures:Synchronized three-dimensional kinematic and kinetic data were collected at 20-minute increments to assess the effect of the FKB on select lower extremity moments and vertical ground reaction forces.Results:Increase in hip moment and a decrease in knee moment were noted immediately after brace application and appeared to persist throughout a one hour bout of exercise.Conclusions:The FKB and the exercise intervention caused decreases in knee joint moments and increases in hip joint moments.

Toe-in Landing Increases the Ankle Inversion Angle and Moment During Single-Leg Landing: Implications in the Prevention of Lateral Ankle Sprains

2017 ◽  
Vol 26 (6) ◽  
pp. 530-535 ◽  
Author(s):  
Yuta Koshino ◽  
Tomoya Ishida ◽  
Masanori Yamanaka ◽  
Mina Samukawa ◽  
Takumi Kobayashi ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Transverse Plane ◽  
Ankle Sprains ◽  
Lateral Ankle ◽  
Ankle Inversion ◽  
Reaction Forces ◽  
Vertical Ground Reaction Forces ◽  
Foot Position

Context:Identifying the foot positions that are vulnerable to lateral ankle sprains is important for injury prevention. The effects of foot position in the transverse plane on ankle biomechanics during landing are unknown.Objective:To examine the effects of toe-in or toe-out positioning on ankle inversion motion and moment during single-leg landing.Design:Repeated measures.Setting:Motion analysis laboratory.Participants:18 healthy participants (9 men and 9 women).Interventions:Participants performed single-leg landing trials from a 30-cm high box under 3 conditions: natural landing, foot internally rotated (toe-in), and foot externally rotated (toe-out).Main Outcome Measures:4 toe-in or toe-out angles were calculated against 4 reference coordinates (laboratory, pelvis, thigh, and shank) in the transverse plane. Ankle inversion angle, angular velocity, and external moment in the 200 ms after initial foot-to-ground contact were compared between the 3 landing conditions.Results:All toe-in or toe-out angles other than those calculated against the shank were significantly different between each of the 3 landing conditions (P < .001). Ankle inversion angle, angular velocity, and moment were highest during toe-in landings (P < .01), while eversion angle and moment were highest during toe-out landings (P < .001). The effect sizes of these differences were large. Vertical ground reaction forces were not different between the 3 landing conditions (P = .290).Conclusions:Toe-in or toe-out positioning during single-leg landings impacts on ankle inversion and eversion motion and moment. Athletes could train not to land with the toe-in positioning to prevent lateral ankle sprains.

Lower Extremity Joint Moments of Collegiate Soccer Players Differ between Genders during a Forward Jump

2008 ◽  
Vol 17 (2) ◽  
pp. 137-147 ◽  
Author(s):  
Joseph M. Hart ◽  
J. Craig Garrison ◽  
Riann Palmieri-Smith ◽  
D. Casey Kerrigan ◽  
Christopher D. Ingersoll
Keyword(s):  
Lower Extremity ◽  
Internal Rotation ◽  
Outcome Measures ◽  
Cruciate Ligament ◽  
Ligament Injury ◽  
Initial Contact ◽  
Joint Angles ◽  
Joint Moments ◽  
Heel Contact ◽  
Hip Internal Rotation

Context:Lower extremity kinetics while performing a single-leg forward jump landing may help explain gender biased risk for noncontact anterior cruciate ligament injury.Objective:Gender comparison of lower extremity joint angles and moments.Design:Static groups comparison.Setting:Motion analysis laboratory.Patients or Other Participants:8 male and 8 female varsity, collegiate soccer athletes.Intervention:5 single-leg landings from a 100cm forward jump.Main Outcome Measures:Peak and initial contact external joint moments and joint angles of the ankle, knee, and hip.Results:At initial heel contact, males exhibited a adduction moment whereas females exhibited a abduction moment at the hip. Females also had significantly less peak hip extension moment and significantly less peak hip internal rotation moment than males had. Females exhibited greater knee adduction and hip internal rotation angles than men did.Conclusions:When decelerating from a forward jump, gender differences exist in forces acting at the hip.

Late Rearfoot Eversion and Lower-limb Internal Rotation Caused by Changes in the Interaction between Forefoot and Support Surface

2009 ◽  
Vol 99 (6) ◽  
pp. 503-511 ◽  
Author(s):  
Thales R. Souza ◽  
Rafael Z. Pinto ◽  
Renato G. Trede ◽  
Renata N. Kirkwood ◽  
Antônio E. Pertence ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Internal Rotation ◽  
Lower Limb ◽  
Repeated Measures ◽  
Three Dimensional ◽  
Support Surface ◽  
Kinetic Chain ◽  
Mechanical Factors ◽  
Lateral Wedges ◽  
Rearfoot Eversion

Background: The influence of distal mechanical factors that change the interaction between the forefoot and the support surface on lower-limb kinematics is not well established. This study investigated the effects of the use of lateral wedges under the forefoot on the kinematics of the lower extremity during the stance phase of walking. Methods: Sixteen healthy young adults participated in this repeated-measures study. They walked wearing flat sandals and laterally wedged sandals, which were medially inclined only in the forefoot. One wedged sandal had a forefoot lateral wedge of 5° and the other wedged sandal had a forefoot lateral wedge of 10°. Kinematic variables of the lower extremity, theoretically considered clinically relevant for injury development, were measured with a three-dimensional motion analysis system. The variables were evaluated for three subphases of stance: loading response, midstance, and late stance. Results: The 5° laterally wedged sandal increased rearfoot eversion during midstance and the 10° laterally wedged sandal increased rearfoot eversion during mid- and late stances, in comparison to the use of flat sandals. The 10° laterally wedged sandal produced greater internal rotation of the shank relative to the pelvis and of the hip joint, during the midstance, also compared to the use of flat sandals. Conclusions: Lateral wedges under the forefoot increase rearfoot eversion during mid-and late stances and may cause proximal kinematic changes throughout the lower-extremity kinetic chain. Distal mechanical factors should be clinically addressed when a patient presents late excessive rearfoot eversion during walking. (J Am Podiatr Med Assoc 99(6): 503–511, 2009)

Effects of Various Midsole Densities of Basketball Shoes on Impact Attenuation during Landing Activities

2005 ◽  
Vol 21 (1) ◽  
pp. 3-17 ◽  
Author(s):  
Songning Zhang ◽  
Kurt Clowers ◽  
Charles Kohstall ◽  
Yeon-Joo Yu
Keyword(s):  
Lower Extremity ◽  
Repeated Measures ◽  
Impact Force ◽  
Shock Attenuation ◽  
Kinematic Data ◽  
Repeated Measures Analysis ◽  
Impact Attenuation ◽  
Reaction Forces ◽  
Lower Extremity Biomechanics ◽  
Evidence Of Impact

The purpose of this study was to examine effects of shoe midsole densities and mechanical demands (landing heights) on impact shock attenuation and lower extremity biomechanics during a landing activity. Nine healthy male college athletes performed 5 trials of step-off landing in each of 9 test conditions, i.e., a combination of landings in shoes of 3 midsole densities (soft, normal, hard) from each of 3 landing potential energy (PE) levels (low, median, high). Ground reaction forces (GRF), accelerations (ACC) of the tibia and forehead, and sagittal kinematic data were sampled simultaneously. A 3 × 3 two-way (surface × height) repeated-measures analysis of variance (ANOVA) was performed on selected kinematic, ACC, and GRF variables; a 3 × 3 × 3 three-way (surface × height × joint) ANOVA was performed on variables related to eccentric muscular work. The GRF results showed that the forefoot peak GRF in the normal and hard midsoles was significantly greater than the soft midsole at the low and median PEs. Rearfoot peak GRF was significantly greater for the hard midsole than for the soft and normal midsoles at the median and high PEs, respectively. The peak head and tibia peak ACC were also attenuated in similar fashion. Kinematic variables did not vary significantly across different midsoles, nor did energy absorbed through lower extremity extensors in response to the increased shoe stiffness. Knee joint extensors were shown to be dominant in attenuating the forefoot impact force across the landing heights. The results showed limited evidence of impact-attenuating benefits of the soft midsole in the basketball shoes.

Electromyographic Evaluation of Abdominal-Muscle Function With and Without Concomitant Pelvic-Floor-Muscle Contraction

2013 ◽  
Vol 22 (2) ◽  
pp. 108-114 ◽  
Author(s):  
Nahid Tahan ◽  
Amir Massoud Arab ◽  
Bita Vaseghi ◽  
Khosro Khademi
Keyword(s):  
Pelvic Floor ◽  
Muscle Contraction ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Pelvic Floor Muscle ◽  
Abdominal Muscle ◽  
Emg Activity ◽  
Abdominal Muscles ◽  
Repeated Measures Design ◽  
Emg Signal

Context:Coactivation of abdominal and pelvic-floor muscles (PFM) is an issue considered by researchers recently. Electromyography (EMG) studies have shown that the abdominal-muscle activity is a normal response to PFM activity, and increase in EMG activity of the PFM concomitant with abdominal-muscle contraction was also reported.Objective:The purpose of this study was to compare the changes in EMG activity of the deep abdominal muscles during abdominal-muscle contraction (abdominal hollowing and bracing) with and without concomitant PFM contraction in healthy and low-back-pain (LBP) subjects.Design:A 2 × 2 repeated-measures design.Setting:Laboratory.Participants:30 subjects (15 with LBP, 15 without LBP).Main Outcome Measures:Peak rectified EMG of abdominal muscles.Results:No difference in EMG of abdominal muscles with and without concomitant PFM contraction in abdominal hollowing (P = .84) and abdominal bracing (P = .53). No difference in EMG signal of abdominal muscles with and without PFM contraction between LBP and healthy subjects in both abdominal hollowing (P = .88) and abdominal bracing (P = .98) maneuvers.Conclusion:Adding PFM contraction had no significant effect on abdominal-muscle contraction in subjects with and without LBP.

Influence of Foot Type and Orthotics on Static and Dynamic Postural Control

2004 ◽  
Vol 13 (1) ◽  
pp. 54-66 ◽  
Author(s):  
Lauren C. Olmsted ◽  
Jay Hertel
Keyword(s):  
Postural Control ◽  
Athletic Training ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Center Of Pressure ◽  
Group Interaction ◽  
Force Plate ◽  
Balance Test ◽  
Repeated Measures Design ◽  
Plate Dynamic

Context:The effects of custom-molded foot orthotics on neuromuscular processes are not clearly understood.Objective:To examine these effects on postural control in subjects with different foot types.Design:Between-groups, repeated-measures design.Setting:Athletic training laboratory.Subjects:30 healthy subjects assigned to groups by foot type: planus (n = 11), rectus (n = 12), or cavus (n = 7).Interventions:Custom-fit semirigid orthotics.Main Outcome Measures:Static postural control was measured on a force plate. Dynamic postural control was measured using the Star Excursion Balance Test. Both measurements were assessed with and without orthotics at baseline and 2 weeks later.Results:For static postural control, a significant condition-by-group interaction was found. Subjects with cavus feet had a decreased center-of-pressure velocity while wearing orthotics. For dynamic postural control, a significant condition-by-direction-by-group interaction was found. Subjects with cavus feet had increased reach distances in 3 of 8 directions while wearing orthotics.Conclusions:Custom orthotics were associated with some improvements in static and dynamic postural control in subjects with cavus feet.

Comparisons of Static and Dynamic Balance Following Training in Aquatic and Land Environments

2006 ◽  
Vol 15 (4) ◽  
pp. 299-311 ◽  
Author(s):  
Aimee E. Roth ◽  
Michael G. Miller ◽  
Marc Ricard ◽  
Donna Ritenour ◽  
Brenda L. Chapman
Keyword(s):  
Outcome Measures ◽  
Repeated Measures ◽  
Dynamic Balance ◽  
Balance Training ◽  
Aquatic Environments ◽  
Repeated Measures Design ◽  
Time Interaction ◽  
Type Design ◽  
Post Test

Context:It has been theorized that aquatic balance training differs from land balance training.Objective:To compare the effects of balance training in aquatic and land environments.Design:Between-groups, repeated-measures design.Setting:Biomechanics laboratory and pool.Participants:24 healthy subjects randomly assigned to aquatic (n = 8), land (n = 10), or control (n = 6) groups.Intervention:Four weeks of balance training.Main Outcome Measures:Balance was measured (pre, mid, post, follow-up). COP variables: radial area, y range, x range in single leg (SL), tandem (T), single leg foam (SLF), and tandem form (TF) stance.Results:A significant condition × time interaction for x range was found, with improvements for SL, SLF, and TF. Radial area improved, with post-test 1.01 ± .23 cm2and follow-up 1.06 ± .18 cm2significantly lower than pretest 1.18 ± .23 cm2. Y range significantly improved, with posttest (4.69 ± 1.02 cm2) lower than pretest (5.89 ± 1.26 cm2). The foam conditions (SLF & TF) were significantly different from non-foam conditions (SL & T) for all variables.Conclusions:Results of this study show that balance training can effectively be performed in both land and aquatic environments.

scholarly journals Biomechanical Analysis of Running in Shoes with Different Heel-to-Toe Drops

2021 ◽  
Vol 11 (24) ◽  
pp. 12144
Author(s):  
Masen Zhang ◽  
Huijuan Shi ◽  
Hui Liu ◽  
Xinglong Zhou
Keyword(s):  
Lower Extremity ◽  
Repeated Measures ◽  
Impact Force ◽  
Three Dimensional ◽  
Knee Extension ◽  
Biomechanical Analysis ◽  
Initial Contact ◽  
Vertical Loading ◽  
Peak Knee ◽  
Running Shoes

The heel-to-toe drop of running shoes is a key parameter influencing lower extremity kinematics during running. Previous studies testing running shoes with lower or larger drops generally used minimalist or maximalist shoes, where the factors outside of the drop may lead to the observed changes in running biomechanics. Therefore, our aim was to compare the strike patterns, impact force, and lower extremity biomechanics when running in shoes that varied only in their drops. Eighteen habitual rearfoot strikers performed trials wearing running shoes with four drop conditions: 15 mm, 10 mm, 5 mm, and without a drop. Three-dimensional (3D) tracks of the reflective markers and impact force were synchronously collected using a video graphic acquisition system and two force plates. The biomechanical parameters were compared among the four drop conditions using one-way ANOVA of repeated measures. A greater foot inclination angle (p = 0.001, ηp2 = 0.36) at initial contact and a lower vertical loading rate (p = 0.002, ηp2 = 0.32) during the standing phase were found when running in shoes with large drops compared with running in shoes without a drop. Running in shoes with large drops, as opposed to without, significantly increased the peak knee extension moment (p = 0.002, ηp2 = 0.27), but decreased the peak ankle eversion moment (p = 0.001, ηp2 = 0.35). These findings suggest that the heel-to-toe drop of running shoes significantly influences the running pattern and the loading on lower extremity joints. Running shoes with large drops may be disadvantageous for runners with knee weakness and advantageous for runners with ankle weakness.

Influence of External Ankle Support on Lower Extremity Joint Mechanics During Drop Landings

2010 ◽  
Vol 19 (2) ◽  
pp. 136-148 ◽  
Author(s):  
Mitchell L. Cordova ◽  
Yosuke Takahashi ◽  
Gregory M. Kress ◽  
Jody B. Brucker ◽  
Alfred E. Finch
Keyword(s):  
Knee Joint ◽  
Lower Extremity ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Angular Displacement ◽  
Joint Mechanics ◽  
Drop Landing ◽  
Joint Displacement ◽  
Ankle Support ◽  
Drop Landings

Objective:To investigate the effects of external ankle support (EAS) on lower extremity joint mechanics and vertical ground-reaction forces (VGRF) during drop landings.Design:A 1 × 3 repeated-measures, crossover design.Setting:Biomechanics research laboratory.Patients:13 male recreationally active basketball players (age 22.3 ± 2.2 y, height 177.5 ± 7.5 cm, mass 72.2 ± 11.4 kg) free from lower extremity pathology for the 12 mo before the study.Interventions:Subjects performed a 1-legged drop landing from a standardized height under 3 different ankle-support conditions.Main Outcome Measures:Hip, knee, and ankle angular displacement along with specific temporal (TGRFz1, TGRFz2; s) and spatial (GRFz1, GRFz2; body-weight units [BW]) characteristics of the VGRF vector were measured during a drop landing.Results:The tape condition (1.08 ± 0.09 BW) demonstrated less GRFz1 than the control (1.28 ± 0.16 BW) and semirigid conditions (1.28 ± 0.21 BW; P < .0001), and GRFz2 was unaffected. For TGRFz1, no-support displayed slower time (0.017 ± 0.004 s) than the semirigid (0.014 ± 0.001 s) and tape conditions (0.014 ± 0.002 s; P < .05). For TGRFz2, no-support displayed slower time (0.054 ±.006 s) than the semirigid (0.050 ± 0.006 s) and tape conditions (0.045 ± 0.004 s; P < .05). Semirigid bracing was slower than the tape condition, as well (P < .05). Ankle-joint displacement was less in the tape (34.6° ± 7.7°) and semirigid (36.8° ± 9.3°) conditions than in no-support (45.7° ± 7.3°; P < .05). Knee-joint displacement was larger in the no-support (45.1° ± 9.0°) than in the semirigid (42.6° ± 6.8°; P < .05) condition. Tape support (43.8° ± 8.7°) did not differ from the semirigid condition (P > .05). Hip angular displacement was not affected by EAS (F2,24 = 1.47, P = .25).Conclusions:EAS reduces ankle- and knee-joint displacement, which appear to influence the spatial and temporal characteristics of GRFz1 during drop landings.

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