Association between increase in vertical ground reaction force loading rate and pain level in women with patellofemoral pain after a patellofemoral joint loading protocol

Individuals with patellofemoral pain (PFP) use different motor strategies during unipodal support in stair climbing activities, which may be assessed by vertical ground reaction force parameters. Thus, the aims of this study were to investigate possible differences in first peak, valley, second peak, and loading rate between recreational female athletes with PFP and pain-free athletes during stair climbing in order to determine the association and prediction capability between these parameters, pain level, and functional status in females with PFP. Thirty-one recreational female athletes with PFP and 31 pain-free recreational female athletes were evaluated with three-dimensional kinetics while performing stair climbing to obtain vertical ground reaction force parameters. A visual analog scale was used to evaluate the usual knee pain. The anterior knee pain scale was used to evaluate knee functional score. First peak and loading rate were associated with pain (r = .46, P = .008; r = .56, P = .001, respectively) and functional limitation (r = .31, P = .049; r = −.36, P = .032, respectively). Forced entry regression revealed the first peak was a significant predictor of pain (36.5%) and functional limitation (28.7%). Our findings suggest that rehabilitation strategies aimed at correcting altered vertical ground reaction force may improve usual knee pain level and self-reported knee function in females with PFP.

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The Relationship Between Vertical Ground Reaction Force, Loading Rate, and Sound Characteristics During a Single-Leg Landing

Journal of Sport Rehabilitation ◽

10.1123/jsr.2018-0260 ◽

2020 ◽

Vol 29 (5) ◽

pp. 541-546

Author(s):

Caroline Lisee ◽

Tom Birchmeier ◽

Arthur Yan ◽

Brent Geers ◽

Kaitlin O’Hagan ◽

...

Keyword(s):

Ground Reaction Force ◽

Loading Rate ◽

Reaction Force ◽

Measurement Techniques ◽

Sound Frequency ◽

Clinical Population ◽

Vertical Ground Reaction Force ◽

Vertical Ground ◽

The Relationship ◽

Linear Loading

Context: Landing kinetic outcomes are associated with injury risk and may be persistently altered after anterior cruciate ligament injury or reconstruction. However, it is challenging to assess kinetics clinically. The relationship between sound characteristics and kinetics during a limited number of functional tasks has been supported as a potential clinical alternative. Objective: To assess the relationship between kinetics and sound characteristics during a single-leg landing task. Design: Observational Setting: Laboratory. Participants: There was total of 26 healthy participants (15 males/11 females, age = 24.8 [3.6] y, height = 176.0 [9.1] cm, mass = 74.9 [14.4] kg, Tegner Activity Scale = 6.1 [1.1]). Intervention: Participants completed single-leg landings onto a force plate while audio characteristics were recorded. Main Outcome Measures: Peak vertical ground reaction force, linear loading rate, instantaneous loading rate, peak sound magnitude, sound frequency were measured. Means and SDs were calculated for each participant’s individual limbs. Spearman rho correlations were used to assess the relationships between audio characteristics and kinetic outcomes. Results: Peak sound magnitude was positively correlated with normalized peak vertical ground reaction force (ρ = .486, P = .001); linear loading rate (ρ = .491, P = .001); and instantaneous loading rate (ρ = .298, P = .03). Sound frequency was negatively correlated with instantaneous loading rate (ρ = −.444, P = .001). Conclusions: Peak sound magnitude may be more helpful in providing feedback about an individual’s normalized vertical ground reaction force and linear loading rate, and sound frequency may be more helpful in providing feedback about instantaneous loading rate. Further refinement in sound measurement techniques may be required before these findings can be applied in a clinical population.

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A 6-Week Transition to Maximal Running Shoes Does Not Change Running Biomechanics

The American Journal of Sports Medicine ◽

10.1177/0363546519826086 ◽

2019 ◽

Vol 47 (4) ◽

pp. 968-973 ◽

Cited By ~ 4

Author(s):

J.J. Hannigan ◽

Christine D. Pollard

Keyword(s):

Ground Reaction Force ◽

Loading Rate ◽

Impact Force ◽

Reaction Force ◽

Vertical Ground Reaction Force ◽

Risk Of Injury ◽

Impact Peak ◽

Running Shoes ◽

Vertical Ground ◽

The Impact

Background: A recent study suggested that maximal running shoes may increase the impact force and loading rate of the vertical ground-reaction force during running. It is currently unknown whether runners will adapt to decrease the impact force and loading rate over time. Purpose: To compare the vertical ground-reaction force and ankle kinematics between maximal and traditional shoes before and after a 6-week acclimation period to the maximal shoe. Study Design: Controlled laboratory study. Methods: Participants ran in a traditional running shoe and a maximal running shoe during 2 testing sessions 6 weeks apart. During each session, 3-dimensional kinematics and kinetics were collected during overground running. Variables of interest included the loading rate, impact peak, and active peak of the vertical ground-reaction force, as well as eversion and dorsiflexion kinematics. Two-way repeated measures analyses of variance compared data within participants. Results: No significant differences were observed in any biomechanical variable between time points. The loading rate and impact peak were higher in the maximal shoe. Runners were still everted at toe-off and landed with less dorsiflexion, on average, in the maximal shoe. Conclusion: Greater loading rates and impact forces were previously found in maximal running shoes, which may indicate an increased risk of injury. The eversion mechanics observed in the maximal shoes may also increase the risk of injury. A 6-week transition to maximal shoes did not significantly change any of these measures. Clinical Relevance: Maximal running shoes are becoming very popular and may be considered a treatment option for some injuries. The biomechanical results of this study do not support the use of maximal running shoes. However, the effect of these shoes on pain and injury rates is unknown.

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Computational Methods Used in the Determination of Loading Rate: Experimental and Clinical Implications

Journal of Applied Biomechanics ◽

10.1123/jab.15.4.404 ◽

1999 ◽

Vol 15 (4) ◽

pp. 404-417 ◽

Cited By ~ 7

Author(s):

C. Mark Woodard ◽

Margaret K. James ◽

Stephen P. Messier

Keyword(s):

Difference Method ◽

Ground Reaction Force ◽

Loading Rate ◽

Reaction Force ◽

Vertical Force ◽

Vertical Ground Reaction Force ◽

Central Difference ◽

Symptomatic Knee Osteoarthritis ◽

Central Difference Method ◽

Vertical Ground

Our purpose was to compare methods of calculating loading rate to the first peak vertical ground reaction force during walking and provide a rationale for the selection of a loading rate algorithm in the analysis of gait in clinical and research environments. Using vertical ground reaction force data collected from 15 older adults with symptomatic knee osteoarthritis and 15 healthy controls, we: (a) calculated loading rate as the first peak vertical force divided by the time from touchdown until the first peak; (b) calculated loading rate as the slope of the least squares regression line using vertical force and time as the dependent and independent variables, respectively; (c) calculated loading rate over discrete intervals using the Central Difference method; and (d) calculated loading rate using vertical force and lime data representing 20% and 90% of the first peak vertical force. The largest loading rate, which may be of greatest clinical importance, occurred when loading rates were calculated using the fewest number of data points. The Central Difference method appeared to maximize our ability to detect differences between healthy and pathologic cohorts. Finally, there was a strong correlation between methods, suggesting that all four methods are acceptable. However, if maximizing the chances of detecting differences between groups is of primary importance, the Central Difference method appears superior.

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A Comparison of Negative Joint Work and Vertical Ground Reaction Force Loading Rates in Chi Runners and Rearfoot-Striking Runners

Journal of Orthopaedic and Sports Physical Therapy ◽

10.2519/jospt.2013.4542 ◽

2013 ◽

Vol 43 (10) ◽

pp. 685-692 ◽

Cited By ~ 26

Author(s):

Donald Lee Goss ◽

Michael T. Gross

Keyword(s):

Ground Reaction Force ◽

Reaction Force ◽

Joint Work ◽

Vertical Ground Reaction Force ◽

Loading Rates ◽

Force Loading ◽

Vertical Ground

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Altered Vertical Ground Reaction Force Components While Walking in Individuals With Chronic Ankle Instability

International Journal of Athletic Therapy & Training ◽

10.1123/ijatt.2018-0117 ◽

2020 ◽

Vol 25 (1) ◽

pp. 27-30

Author(s):

Erik A. Wikstrom ◽

Kyeongtak Song ◽

Kimmery Migel ◽

Chris J. Hass

Keyword(s):

Ground Reaction Force ◽

Loading Rate ◽

Ankle Instability ◽

Reaction Force ◽

Chronic Ankle Instability ◽

Vertical Ground Reaction Force ◽

Time To Peak ◽

Vertical Ground ◽

Force Components

Aberrant loading is a mechanism by which individuals with chronic ankle instability (CAI) may negatively impact cartilage health and therefore long-term health outcomes. We aimed to quantify walking vertical ground reaction force (vGRF) component differences between those with and without CAI. Participants (n = 36) walked barefoot overground at a self-selected comfortable pace. Normalized peak vGRF, time to peak vGRF, and normalized loading rate were calculated. Higher normalized loading rates (CAI: 5.69 ± 0.62 N/BW/s; controls: 5.30 ± 0.44 N/BW/s, p = .034) and less time to peak vGRF (CAI: 1.48 ± 0.18 s; controls: 1.62 ± 0.16 s, p = .018) were observed in those with CAI. In conclusion, those with CAI demonstrate a higher normalized loading rate and less time to peak vGRF compared to controls.

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Patellofemoral Joint Loading During Single-Leg Hopping Exercises

Journal of Sport Rehabilitation ◽

10.1123/jsr.2019-0135 ◽

2020 ◽

Vol 29 (8) ◽

pp. 1131-1136

Author(s):

Abbigail Ristow ◽

Matthew Besch ◽

Drew Rutherford ◽

Thomas W. Kernozek

Keyword(s):

Patellofemoral Joint ◽

Stance Phase ◽

Loading Rate ◽

Reaction Force ◽

Patellofemoral Pain ◽

Camera Motion ◽

Joint Loading ◽

Joint Reaction Force ◽

Joint Stress ◽

Significant Difference

Context: Single-leg hopping is used to assess a dynamic knee stability. Patellofemoral pain is often experienced during these exercises, and different cadences of jumping are often used in rehabilitation for those with patellofemoral pain. No studies to date have examined patellofemoral joint loading during single-leg hopping exercise with different hopping cadences. Objective: To determine if single-leg hopping at 2 different cadences (50 and 100 hops per minute [HPM]) leads to a significant difference in patellofemoral joint loading variables. Setting: University research laboratory. Participants: Twenty-five healthy college-aged females (age 22.3 [1.8] y, height 171.4 [6.3] cm, weight 67.4 [9.5] kg, Tegner Activity Scale 4.75 [1.75]) participated. Main Outcome Measures: Three-dimensional kinematic and kinetic data were measured using a 15-camera motion capture system and force platform. Static optimization was used to calculate muscle forces and then used in a musculoskeletal model to determine patellofemoral joint stress (PFJS), patellofemoral joint reaction force (PFJRF), quadriceps force (QF), and PFJRF loading rate, during the first and last 50% of stance phase. Results: Greater maximal PFJRF occurred at 100 HPM, whereas greater PFJRF loading rate occurred at 50 HPM. However, overall peak QF and peak PFJS were not different between the 2 cadences. At 50 HPM, there was greater PFJS, PFJRF, peak PFJRF loading rate, and peak QF during the first 50% of stance when compared with the last 50%. Conclusion: Training at 50 HPM may reduce PFJRF and PFJRF loading rate, but not PFJS or QF. Patellofemoral joint loading variables had significantly higher values during the first half of the stance phase at the 50 HPM cadence. This may be important with training individuals with patellofemoral pain.

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Inter-limb weight transfer strategy during walking after unilateral transfemoral amputation

Scientific Reports ◽

10.1038/s41598-021-84357-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ryo Amma ◽

Genki Hisano ◽

Hiroto Murata ◽

Matthew J. Major ◽

Hiroshi Takemura ◽

...

Keyword(s):

Ground Reaction Force ◽

Loading Rate ◽

Regression Line ◽

Reaction Force ◽

Transfemoral Amputation ◽

Vertical Ground Reaction Force ◽

Unloading Rate ◽

Vertical Ground ◽

Walking Speeds ◽

Weight Transfer

AbstractAlthough weight transfer is an important component of gait rehabilitation, the biomechanical strategy underlying the vertical ground reaction force loading/unloading in individuals with unilateral transfemoral amputation between intact and prosthetic limbs remains unclear. We investigated weight transfer between limbs at different walking speeds in 15 individuals with unilateral transfemoral amputation and 15 individuals without amputation as controls, who walked on an instrumented treadmill. The normalized unloading and loading rates were calculated as the slope of decay and rise phase of the vertical ground reaction force, respectively. We performed linear regression analyses for trailing limb’s unloading rate and leading limb’s loading rate between the prosthetic, intact, and control limbs. While loading rate increased with walking speed in all three limbs, the greatest increase was observed in the intact limb. In contrast to the other limbs, the prosthetic limb unloading rate was relatively insensitive to speed changes. Consequently, the regression line between trailing prosthetic and leading intact limbs deviated from other relationships. These results suggest that weight transfer is varied whether the leading or trailing limb is the prosthetic or intact side, and the loading rate of the leading limb is partially affected by the unloading rate of the contralateral trailing limb.

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Running ground reaction forces across footwear conditions are predicted from the motion of two body mass components

Journal of Applied Physiology ◽

10.1152/japplphysiol.00925.2018 ◽

2019 ◽

Vol 126 (5) ◽

pp. 1315-1325 ◽

Cited By ~ 3

Author(s):

Andrew B. Udofa ◽

Kenneth P. Clark ◽

Laurence J. Ryan ◽

Peter G. Weyand

Keyword(s):

Ground Reaction Force ◽

Lower Limb ◽

Reaction Force ◽

Ground Reaction Forces ◽

Vertical Ground Reaction Force ◽

Time Patterns ◽

Foot Strike ◽

Reaction Forces ◽

Vertical Ground ◽

Force Time

Although running shoes alter foot-ground reaction forces, particularly during impact, how they do so is incompletely understood. Here, we hypothesized that footwear effects on running ground reaction force-time patterns can be accurately predicted from the motion of two components of the body’s mass (mb): the contacting lower-limb (m1 = 0.08mb) and the remainder (m2 = 0.92mb). Simultaneous motion and vertical ground reaction force-time data were acquired at 1,000 Hz from eight uninstructed subjects running on a force-instrumented treadmill at 4.0 and 7.0 m/s under four footwear conditions: barefoot, minimal sole, thin sole, and thick sole. Vertical ground reaction force-time patterns were generated from the two-mass model using body mass and footfall-specific measures of contact time, aerial time, and lower-limb impact deceleration. Model force-time patterns generated using the empirical inputs acquired for each footfall matched the measured patterns closely across the four footwear conditions at both protocol speeds ( r2 = 0.96 ± 0.004; root mean squared error = 0.17 ± 0.01 body-weight units; n = 275 total footfalls). Foot landing angles (θF) were inversely related to footwear thickness; more positive or plantar-flexed landing angles coincided with longer-impact durations and force-time patterns lacking distinct rising-edge force peaks. Our results support three conclusions: 1) running ground reaction force-time patterns across footwear conditions can be accurately predicted using our two-mass, two-impulse model, 2) impact forces, regardless of foot strike mechanics, can be accurately quantified from lower-limb motion and a fixed anatomical mass (0.08mb), and 3) runners maintain similar loading rates (ΔFvertical/Δtime) across footwear conditions by altering foot strike angle to regulate the duration of impact. NEW & NOTEWORTHY Here, we validate a two-mass, two-impulse model of running vertical ground reaction forces across four footwear thickness conditions (barefoot, minimal, thin, thick). Our model allows the impact portion of the impulse to be extracted from measured total ground reaction force-time patterns using motion data from the ankle. The gait adjustments observed across footwear conditions revealed that runners maintained similar loading rates across footwear conditions by altering foot strike angles to regulate the duration of impact.

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