Effects of Knee Extension Constraint Training on Knee Flexion Angle and Peak Impact Ground-Reaction Force

Small knee flexion angle during landing has been proposed as a potential risk factor for sustaining noncontact ACL injury. A brace that promotes increased knee flexion and decreased posterior ground reaction force during landing may prove to be advantageous for developing prevention strategies. Forty male and forty female recreational athletes were recruited. Three-dimensional videographic and ground reaction force data in a stop-jump task were collected in three conditions. Knee flexion angle at peak posterior ground reaction force, peak posterior ground reaction force, the horizontal velocity of approach run, the vertical velocity at takeoff, and the knee flexion angle at takeoff were compared among conditions: knee extension constraint brace, nonconstraint brace, and no brace. The knee extension constraint brace significantly increased knee flexion angle at peak posterior ground reaction force. Both knee extension constraint brace and nonconstraint brace significantly decreased peak posterior ground reaction force during landing. The brace and knee extension constraint did not significantly affect the horizontal velocity of approach run, the vertical velocity at takeoff, and the knee flexion angle at takeoff. A knee extension constraint brace exhibits the ability to modify the knee flexion angle at peak posterior ground reaction force and peak posterior ground reaction force during landing.

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Effects of an Intervention Program on Lower Extremity Biomechanics in Stop-Jump and Side-Cutting Tasks

The American Journal of Sports Medicine ◽

10.1177/0363546518793393 ◽

2018 ◽

Vol 46 (12) ◽

pp. 3014-3022 ◽

Cited By ~ 4

Author(s):

Chen Yang ◽

Wanxiang Yao ◽

William E. Garrett ◽

Deborah L. Givens ◽

Jonathon Hacke ◽

...

Keyword(s):

Ground Reaction Force ◽

Knee Flexion ◽

Intervention Program ◽

Reaction Force ◽

Intervention Group ◽

Collegiate Athletes ◽

Flexion Angle ◽

Control Group ◽

Knee Flexion Angle ◽

Intervention Effects

Background: Anterior cruciate ligament (ACL) injury is one of the most common injuries in sport. To reduce the risk of noncontact ACL injury, it is critical to understand the effects of an intervention program on neuromuscular control–related biomechanical risk factors. Hypothesis: A newly developed 4-week intervention program would significantly increase the knee flexion angle at peak impact posterior ground-reaction force and would significantly decrease the peak impact posterior and vertical ground-reaction forces in the stop-jump and side-cutting tasks, while the intervention effects would be retained after the training was completed. Study Design: Controlled laboratory study. Methods: A total of 22 male and 18 female collegiate basketball and volleyball players with biomechanical characteristics associated with increased risk of ACL injury were recruited and randomly assigned to either the intervention group or the control group. The intervention group executed a program to improve landing techniques through strength and plyometric training 3 times a week for 4 weeks while participating in their regular training. The control group participated in only their regular training for 4 weeks. Three-dimensional kinematic and kinetic data in the stop-jump and side-cutting tasks were collected at week 0 (the beginning of the study) and at the ends of weeks 4, 8, 16, and 20. Knee flexion angle and ground-reaction forces were calculated. Analyses of variance with a mixed design were performed to determine the intervention effects and the retention of intervention effects for each sex. Results: Male participants in the intervention group significantly increased the knee flexion angle at peak impact posterior ground-reaction force in the stop-jump task at weeks 8, 12, and 20 when compared with that at week 0 and with the male control group ( P ≤ .002). No significant intervention effects on knee flexion angle and ground-reaction force were found in the side-cutting task for male participants. No significant interaction effects on takeoff velocities were detected in any task for male participants. No significant intervention effects on knee flexion angle and ground-reaction force were found in any task for female participants. Vertical takeoff velocity in the stop-jump task was significantly lower in the intervention group at week 20 compared with the control group ( P = .011). Conclusion: A 4-week intervention program significantly increased the knee flexion angle at peak impact posterior ground-reaction force of male collegiate athletes in the stop-jump task without significant effect on the performance of the task. This intervention effect was retained for at least 16 weeks after the training was completed. The intervention program, however, did not affect knee flexion angle and ground-reaction force in any task for female collegiate athletes. A reduction in vertical takeoff velocity of the stop-jump task was observed for female collegiate athletes 16 weeks after the intervention. Clinical Relevance: The intervention program with strength conditioning and plyometric exercises could modify landing biomechanics of male collegiate athletes in a stop-jump task. The intervention program may be a useful tool for preventing noncontact ACL injury for male collegiate athletes.

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The Kinematics and Kinetics Analysis of the Lower Extremity in the Landing Phase of a Stop-jump Task

The Open Biomedical Engineering Journal ◽

10.2174/1874120701509010103 ◽

2015 ◽

Vol 9 (1) ◽

pp. 103-107 ◽

Cited By ~ 3

Author(s):

L Yin ◽

D Sun ◽

Q.C Mei ◽

Y.D Gu ◽

J.S Baker ◽

...

Keyword(s):

Lower Extremity ◽

Ground Reaction Force ◽

Knee Flexion ◽

Reaction Force ◽

Flexion Angle ◽

Contact Phase ◽

Peak Knee ◽

Significant Difference ◽

The Impact ◽

Kinematics And Kinetics

Large number of studies showed that landing with great impact forces may be a risk factor for knee injuries. The purpose of this study was to illustrate the different landing loads to lower extremity of both genders and examine the relationships among selected lower extremity kinematics and kinetics during the landing of a stop-jump task. A total of 35 male and 35 female healthy subjects were recruited in this study. Each subject executed five experiment actions. Lower extremity kinematics and kinetics were synchronously acquired. The comparison of lower extremity kinematics for different genders showed significant difference. The knee and hip maximum flexion angle, peak ground reaction force and peak knee extension moment have significantly decreased during the landing of the stop-jump task among the female subjects. The hip flexion angle at the initial foot contact phase showed significant correlation with peak ground reaction force during landing of the stop-jump task (r=-0.927, p<0.001). The knee flexion angle at the initial foot contact phase had significant correlation with peak ground reaction force and vertical ground reaction forces during landing of the stop-jump task (r=-0.908, p<0.001; r=0.812, P=0.002). A large hip and knee flexion angles at the initial foot contact with the ground did not necessarily reduce the impact force during landing, but active hip and knee flexion motions did. The hip and knee flexion motion of landing was an important technical factor that affects anterior cruciate ligament (ACL) loading during the landing of the stop-jump task.

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Patellofemoral Joint Stress during Running with Added Load in Females

International Journal of Sports Medicine ◽

10.1055/a-1088-5467 ◽

2020 ◽

Vol 41 (06) ◽

pp. 412-418

Author(s):

Molly Kujawa ◽

Aleyna Goerlitz ◽

Drew Rutherford ◽

Thomas W. Kernozek

Keyword(s):

Knee Flexion ◽

Patellofemoral Joint ◽

Reaction Force ◽

Step Length ◽

Force Platform ◽

Flexion Angle ◽

Knee Flexion Angle ◽

Peak Knee ◽

Foot Strike ◽

Quadriceps Force

AbstractPatellofemoral joint (PFJ) pain syndrome is a commonly reported form of pain in female runners and military personnel. Increased PFJ stress may be a contributing factor. Few studies have examined PFJ stress running with added load. Our purpose was to analyze PFJ stress, PFJ reaction force, quadriceps force, knee flexion angle, and other kinematic and temporospatial variables running with and without a 9 kg load. Nineteen females ran across a force platform with no added load and 9.0 kg weight vest. Kinematic data were collected using 3D motion capture and kinetic data with a force platform. Muscle forces were estimated using a musculoskeletal model, and peak PFJ loading variables were calculated during stance. Multivariate analyses were run on PFJ loading variables and on cadence, step length and foot strike index. Differences were shown in PFJ stress, PFJ reaction force, peak knee flexion angle and quadriceps force. Joint specific kinetic variables increased between 5–16% with added load. PFJ loading variables increased with 9 kg of added load without changes in cadence, step length, or foot strike index compared to no load. Added load appears to increase the PFJ loading variables associated with PFJ pain in running.

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Quadriceps Neuromuscular Function and Jump-Landing Sagittal-Plane Knee Biomechanics After Anterior Cruciate Ligament Reconstruction

Journal of Athletic Training ◽

10.4085/1062-6050-306-16 ◽

2018 ◽

Vol 53 (2) ◽

pp. 135-143 ◽

Cited By ~ 18

Author(s):

Sarah H. Ward ◽

J. Troy Blackburn ◽

Darin A. Padua ◽

Laura E. Stanley ◽

Matthew S. Harkey ◽

...

Keyword(s):

Knee Flexion ◽

Sagittal Plane ◽

Neuromuscular Function ◽

Knee Extension ◽

Spinal Reflex ◽

Flexion Angle ◽

Voluntary Activation ◽

Knee Flexion Angle ◽

Jump Landing ◽

Peak Knee

Context: Aberrant biomechanics may affect force attenuation at the knee during dynamic activities, potentially increasing the risk of sustaining a knee injury or hastening the development of osteoarthritis after anterior cruciate ligament reconstruction (ACLR). Impaired quadriceps neuromuscular function has been hypothesized to influence the development of aberrant biomechanics. Objective: To determine the association between quadriceps neuromuscular function (strength, voluntary activation, and spinal-reflex and corticomotor excitability) and sagittal-plane knee biomechanics during jump landings in individuals with ACLR. Design: Cross-sectional study. Setting: Research laboratory. Patients or Other Participants: Twenty-eight individuals with unilateral ACLR (7 men, 21 women; age = 22.4 ± 3.7 years, height = 1.69 ± 0.10 m, mass = 69.4 ± 10.1 kg, time postsurgery = 52 ± 42 months). Main Outcome Measure(s): We quantified quadriceps spinal-reflex excitability via the Hoffmann reflex normalized to maximal muscle response (H : M ratio), corticomotor excitability via active motor threshold, strength as knee-extension maximal voluntary isometric contraction (MVIC), and voluntary activation using the central activation ratio (CAR). In a separate session, sagittal-plane kinetics (peak vertical ground reaction force [vGRF] and peak internal knee-extension moment) and kinematics (knee-flexion angle at initial contact, peak knee-flexion angle, and knee-flexion excursion) were collected during the loading phase of a jump-landing task. Separate bivariate associations were performed between the neuromuscular and biomechanical variables. Results: In the ACLR limb, greater MVIC was associated with greater peak knee-flexion angle (r = 0.38, P = .045) and less peak vGRF (r = −0.41, P = .03). Greater CAR was associated with greater peak internal knee-extension moment (ρ = −0.38, P = .045), and greater H : M ratios were associated with greater peak vGRF (r = 0.45, P = .02). Conclusions: Greater quadriceps MVIC and CAR may provide better energy attenuation during a jump-landing task. Individuals with greater peak vGRF in the ACLR limb possibly require greater spinal-reflex excitability to attenuate greater loading during dynamic movements.

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Gait Training Using a Hip-Wearable Robotic Exoskeleton After Total Knee Arthroplasty: A Case Report

Geriatric Orthopaedic Surgery & Rehabilitation ◽

10.1177/2151459320966483 ◽

2020 ◽

Vol 11 ◽

pp. 215145932096648

Author(s):

Kazunori Koseki ◽

Hirotaka Mutsuzaki ◽

Kenichi Yoshikawa ◽

Yusuke Endo ◽

Atsushi Kanazawa ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Knee Flexion ◽

Walking Speed ◽

Gait Training ◽

Gait Pattern ◽

Knee Extension ◽

Flexion Angle ◽

Knee Flexion Angle ◽

Total Knee

The Honda Walking Assist® (HWA) is a light and easy wearable robot device for gait training, which assists patients’ hip flexion and extension movements to guide hip joint movements during gait. However, the safety and feasibility of gait training with HWA after total knee arthroplasty (TKA) remains unclear. Thus, we aimed to evaluate the safety and feasibility of this gait training intervention using HWA for a patient who underwent TKA. The patient was a 76-year-old female who underwent a left TKA. Gait training using HWA was conducted for 18 sessions in total, from 1 to 5 weeks after TKA. To verify the recovery process after TKA surgery, knee function parameters and walking ability were measured at pre-TKA and 1, 2, 4, and 8 weeks after TKA. The gait patterns at self-selected walking speed (SWS) without HWA at pre- and 5 weeks after TKA were measured by using 3-dimensional (3D) gait analysis. The patient completed a total of 18 gait training interventions with HWA without any adverse complications such as knee pain and skin injury. The postoperative knee extension range of motion (ROM), knee extension torque, SWS, and maximum walking speed were remarkably improved. Regarding gait kinematic parameters, though this patient had a characteristic gait pattern with decreased knee ROM (called stiff knee gait) preoperatively, the knee flexion angle at 5 weeks after TKA showed knee flexion movement at loading response phase (LR; called double knee action), increased knee ROM during gait, and increased knee flexion angle at swing phase. In this case, the gait training using HWA was safe and feasible, and could be effective for the early improvement of gait ability, hip function, and gait pattern after TKA.

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Progression of Fatigue Modifies Primary Contributors to Ground Reaction Forces During Drop Landing

Journal of Human Kinetics ◽

10.2478/hukin-2021-0052 ◽

2021 ◽

Vol 76 (1) ◽

pp. 161-173

Author(s):

Qiang Zhang ◽

Mianfang Ruan ◽

Navrag B. Singh ◽

Lingyan Huang ◽

Xin Zhang ◽

...

Keyword(s):

Knee Joint ◽

Ground Reaction Force ◽

Knee Flexion ◽

Reaction Force ◽

Joint Stiffness ◽

Knee Flexion Angle ◽

Vertical Ground Reaction Force ◽

Severe Fatigue ◽

Peak Knee ◽

Vertical Ground

Abstract Few studies have focused on the effect of fatigue severity on landing strategy. This study aimed to investigate the effect of fatigue progression on ground reaction force during landing. Eighteen participants performed a fatigue exercise protocol. Then participants performed drop landings at three levels of fatigue: no fatigue, medium fatigue, and severe fatigue. Multiple linear regression was conducted to identify the predictors of the peak vertical ground reaction force at each level of fatigue. Two-way ANOVAs were conducted to test the effect of fatigue on the vertical ground reaction force and the predictors. For the vertical ground reaction force, the knee joint stiffness and the knee angle at initial contact were the main predictors at no fatigue. The peak knee flexion angle and knee power were the main predictors at medium fatigue. However, the peak ankle plantarflexion moments became the main predictor at severe fatigue. The vertical ground reaction force decreased from no to medium fatigue (p = 0.001), and then increased from medium to severe fatigue (p = 0.034). The knee joint stiffness decreased from no to medium fatigue (p = 0.049), and then remained unchanged from medium to severe fatigue. The peak knee flexion angle increased from no to medium fatigue (p = 0.001), and then slightly decreased from medium to severe fatigue (p = 0.051). The results indicate that fatigue progression causes a transition from stiff to soft landing, and then to stiff landing. Participants used ankle joints more to control the landing intensity at severe fatigue.

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Distal Femoral Extension Osteotomy and Patellar Tendon Advancement in Management of Fixed Knee Flexion Deformity and Crouch Gait in Cerebral Palsy

QJM ◽

10.1093/qjmed/hcab104.012 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Khaled Mohamed Emara ◽

Sherif Ahmed El-Ghazaly ◽

Mahmoud Ali Mahran ◽

Mahmoud Ahmed Alsehemy

Keyword(s):

Cerebral Palsy ◽

Patellar Tendon ◽

Knee Flexion ◽

Knee Extension ◽

Flexion Angle ◽

Knee Flexion Angle ◽

Flexion Deformity ◽

The Mean ◽

Knee Flexion Deformity

Abstract Background Cerebral palsy (CP) is generally associated with musculoskeletal deformities that occur during body growth. Fixed knee flexion deformity (FKFD) results from long standing knee flexion that is due to progressive contracture of spastic hamstrings combined with a quadriceps weakness. Fixed knee flexion compromises the passive mechanisms of joint stabilization at mid and terminal stance in children with CP. The aim of this study is to highlight the results of distal femoral extension osteotomy and patellar tendon advancement (DFEO + PTA) for management of FKFD in crouching CP patients with spastic or mixed tone diplegic ambulatory cerebral palsy children. Patients and Methods A prospective study was conducted involving twenty CP patients with fixed knee flexion deformity (14 males and 6 females). The 20 cases with fixed knee flexion deformity were GMFCS level II (4 cases), and III (16 cases). All patients were clinically and radiologically assessed according to knee flexion angle, extension lag, koshino index and the Gross motor function measure pre- and post-operative. All patients underwent DFEO ± PTA. Eighteen limbs had DFEO on the RT side, and twenty on the LT side. Results The mean age of the patients was 11.18±3.23 (6-16) years. The period of follow up ranged from 12 to 24 months (The mean follow up was 16.20 ± 2.46). At last follow up, the median knee flexion angle improved from 25 to 0. The median extension lag improved from 17.5 to 0. The mean koshino index improved from 1.59 ± 0.32 to 1.05 ± 0.10. the GMFM improved from 52.86 ± 7.36 to 68.15 ± 5. 82. Conclusion The combined procedure (DFEO + PTA) is effective in increasing knee extension in the stance phase, reducing knee pain and improving knee extension strength.

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A high degree of knee flexion after TKA promotes the ability to perform high-flexion activities and patient satisfaction in Asian population

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04369-4 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Hyuk-Soo Han ◽

Jong Seop Kim ◽

Bora Lee ◽

Sungho Won ◽

Myung Chul Lee

Keyword(s):

Quality Of Life ◽

Patient Satisfaction ◽

Clinical Data ◽

Knee Flexion ◽

Male Gender ◽

Flexion Angle ◽

Knee Flexion Angle ◽

High Flexion ◽

Standing Up

Abstract Background This study investigated whether achieving a higher degree of knee flexion after TKA promoted the ability to perform high-flexion activities, as well as patient satisfaction and quality of life. Methods Clinical data on 912 consecutive primary TKA cases involving a single high-flexion posterior stabilized fixed-bearing prosthesis were retrospectively analyzed. Demographic and clinical data were collected, including knee flexion angle, the ability to perform high-flexion activities, and patient satisfaction and quality of life. Results Of the cases, 619 (68%) achieved > 130° of knee flexion after TKA (high flexion group). Knee flexion angle and clinical scores showed significant annual changes, with the maximum improvement seen at 5 years and slight deterioration observed at 10 years postoperatively. In the high flexion group, more than 50% of the patients could not kneel or squat, and 35% could not stand up from on the floor. Multivariate analysis revealed that > 130° of knee flexion, the ability to perform high-flexion activities (sitting cross-legged and standing up from the floor), male gender, and bilateral TKA were significantly associated with patient satisfaction after TKA, while the ability to perform high-flexion activities (sitting cross-legged and standing up from the floor), male gender, and bilateral TKA were significantly associated with patient quality of life after TKA. Conclusions High knee flexion angle (> 130°) after TKA increased the ease of high-flexion activities and patient satisfaction. The ease of high-flexion activities also increased quality of life after TKA in our Asian patients, who frequently engage in these activities in daily life.

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Kinematic Comparison between Medially Congruent and Posterior-Stabilized Third-Generation TKA Designs

Journal of Functional Morphology and Kinesiology ◽

10.3390/jfmk6010027 ◽

2021 ◽

Vol 6 (1) ◽

pp. 27

Author(s):

Stefano Ghirardelli ◽

Jessica L. Asay ◽

Erika A. Leonardi ◽

Tommaso Amoroso ◽

Thomas P. Andriacchi ◽

...

Keyword(s):

Knee Flexion ◽

Knee Kinematics ◽

Primary Total Knee Arthroplasty ◽

Flexion Angle ◽

Heel Strike ◽

Third Generation ◽

Knee Flexion Angle ◽

Posterior Stabilized ◽

Rotational Angle ◽

Peak Knee

Background: This study compares knee kinematics in two groups of patients who have undergone primary total knee arthroplasty (TKA) using two different modern designs: medially congruent (MC) and posterior-stabilized (PS). The aim of the study is to demonstrate only minimal differences between the groups. Methods: Ten TKA patients (4 PS, 6 MC) with successful clinical outcomes were evaluated through 3D knee kinematics analysis performed using a multicamera optoelectronic system and a force platform. Extracted kinematic data included knee flexion angle at heel-strike (KFH), peak midstance knee flexion angle (MSKFA), maximum and minimum knee adduction angle (KAA), and knee rotational angle at heel-strike. Data were compared with a group of healthy controls. Results: There were no differences in preferred walking speed between MC and PS groups, but we found consistent differences in knee function. At heel-strike, the knee tended to be more flexed in the PS group compared to the MC group; the MSKFA tended to be higher in the PS group compared to the MC group. There was a significant fluctuation in KAA during the swing phase in the PS group compared to the MC group, PS patients showed a higher peak knee flexion moment compared to MC patients, and the PS group had significantly less peak internal rotation moments than the MC group. Conclusions: Modern, third-generation TKA designs failed to reproduce normal knee kinematics. MC knees tended to reproduce a more natural kinematic pattern at heel-strike and during axial rotation, while PS knees showed better kinematics during mid-flexion.

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