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Clinical Biomechanics (Bristol, Avon) Feb 2013Although total knee arthroplasty reduces pain and improves function, patients continue to walk with asymmetrical movement patterns, that may affect muscle activation and...
BACKGROUND
Although total knee arthroplasty reduces pain and improves function, patients continue to walk with asymmetrical movement patterns, that may affect muscle activation and joint loading patterns. The purpose of this study was to evaluate the specific biomechanical abnormalities that persist after total knee arthroplasty and examine the neuromuscular mechanisms that may contribute to these asymmetries.
METHODS
Dynamic joint stiffness at the hip, knee and ankle, as well as co-contraction at the knee and ankle, were compared between the operated and non-operated limbs of 32 subjects who underwent total knee arthroplasty and 21 subjects without lower extremity impairment.
FINDINGS
Subjects after total knee arthroplasty demonstrated higher dynamic joint stiffness in the operated knee compared to the non-operated knee (0.056 (0.023) Nm/kg/m/deg vs. 0.043 (0.016) Nm/kg/m/deg, P=0.003) and the knees from a control group without lower extremity pathology (controls: 0.042 (0.015) Nm/kg/m/deg, P=0.017). No differences were found between limbs or groups for dynamic joint stiffness at the hip or ankle. There was no relationship between dynamic joint stiffness at the knee and ankle and the amount of co-contraction between antagonistic muscles at those joints.
INTERPRETATION
Patients after total knee arthroplasty walk with less knee joint excursion and greater knee stiffness, although no differences were found between groups for stiffness at the hip or ankle. Mechanisms other than co-contraction are likely the underlying cause of the altered knee mechanics. These findings are clinically relevant because the goal should be to create interventions to reduce these abnormalities and increase function.
Topics: Aged; Analysis of Variance; Ankle Joint; Arthroplasty, Replacement, Knee; Biomechanical Phenomena; Electromyography; Female; Gait; Hip Joint; Humans; Knee Joint; Male; Middle Aged; Muscle Contraction; Range of Motion, Articular
PubMed: 23219062
DOI: 10.1016/j.clinbiomech.2012.11.008 -
Journal of Healthcare Engineering 2020While individual ankle and metatarsophalangeal joint stiffness is related to training intensity and sport performances, sport athletes may develop specific passive joint...
While individual ankle and metatarsophalangeal joint stiffness is related to training intensity and sport performances, sport athletes may develop specific passive joint stiffness among the spectrum from endurance to powerful types of sports. The objective of this study examined whether marathon runners, basketball players, and other sports athletes would demonstrate distinct passive ankle and metatarsophalangeal joint stiffness as well as vertical stiffness. Fifteen marathon runners, nineteen basketball players, and seventeen other sports athletes performed both joint stiffness measurement and single-leg hopping tests. We used a computerized dynamometer to control foot alignment and speed for passive ankle and metatarsophalangeal joint stiffness measurements. We calculated vertical stiffness by body deceleration and body mass displacement during hopping on the force platform. One-way ANOVA was performed to identify the group differences. Bivariate correlation test was also performed among ankle, metatarsophalangeal, and vertical stiffness. The basketball group displayed 13% higher ankle passive stiffness than the other sports players group ( = 0.03). Metatarsophalangeal joint passive stiffness in sitting and standing positions was 23% higher in the basketball group than the runner and other sports athlete groups ( < 0.01). However, there was no significant group differences in metatarsophalangeal joint passive stiffness and vertical stiffness. Significant correlations among all stiffness variables were determined ( < 0.05). These findings indicate that ankle and metatarsophalangeal joint passive stiffness, rather than vertical leg stiffness, would be in relation to types of sports participation. Ankle and toe strengthening exercises could improve basketball players' performance and prevent injury.
Topics: Adult; Ankle Joint; Athletic Performance; Basketball; Humans; Male; Metatarsophalangeal Joint; Movement; Running; Young Adult
PubMed: 32257087
DOI: 10.1155/2020/9025015 -
Journal of Athletic Training 2008The valgus stress test is used clinically to assess injury to the medial knee structures in 2 positions: full extension and some degree of flexion. The amount of flexion...
CONTEXT
The valgus stress test is used clinically to assess injury to the medial knee structures in 2 positions: full extension and some degree of flexion. The amount of flexion used to "isolate" the medial collateral ligament is not consistent in the literature, but most studies have shown that stiffness of the ligaments was consistent between the limbs.
OBJECTIVE
To determine (1) if the stiffness of the medial knee structures was the same bilaterally, and (2) if the stiffness was different in full extension compared with 20 degrees of knee flexion.
DESIGN
Criterion standard, before-after design.
SETTING
University research laboratory.
PATIENTS OR OTHER PARTICIPANTS
Both knees of 45 healthy and active volunteers (26 females, 19 males; age = 23.2 +/- 3.96 years, height = 170.6 +/- 7.75 cm, mass = 74.2 +/- 15.14 kg) were studied.
INTERVENTION(S)
A valgus force of 60 N was applied to the lateral aspect of both knees in full extension and in 20 degrees of flexion.
MAIN OUTCOME MEASURE(S)
The slope of the force-strain line of the medial knee during a valgus force was calculated using the LigMaster arthrometer.
RESULTS
Slope means in full extension were 16.1 +/- 3.3 (right knee) and 15.8 +/- 3.1(left knee). Means for 20 degrees of flexion were 12.2 +/- 3.1 (right) and 11.7 +/- 2.8 (left). Stiffness was greater when the knee was in full extension versus 20 degrees of flexion (t(44) = 12.04, P < .001). No difference was noted between the slopes of the 2 knees in extension (t(44) = 0.74, P = .46) or in flexion (t(44) = 1.2, P = .27).
CONCLUSIONS
These findings support the use of the contralateral knee as a control. Further, the valgus stress test should be performed in full extension and in some degree of flexion to assess the different restraining structures of the medial tibiofemoral joint.
Topics: Adult; Anterior Cruciate Ligament; Arthrometry, Articular; Collateral Ligaments; Exercise Test; Female; Humans; Knee Joint; Ligaments, Articular; Male; Medial Collateral Ligament, Knee; Muscle Contraction; Muscle, Skeletal; Posterior Cruciate Ligament; Prospective Studies; Range of Motion, Articular
PubMed: 18345340
DOI: 10.4085/1062-6050-43.2.157 -
Journal of Orthopaedic Research :... Sep 2020Deviations are often identified at individual joints in the gait analysis of patients with cerebral palsy. Previous gait studies on hemiplegic cerebral palsy (HCP) have... (Comparative Study)
Comparative Study
Deviations are often identified at individual joints in the gait analysis of patients with cerebral palsy. Previous gait studies on hemiplegic cerebral palsy (HCP) have focused mainly on deviations of the affected side. The current study aimed to quantify and compare the joint and leg stiffness, the contributions of skeletal and muscular components, and the associated joint angles and moments of the affected and nonaffected lower limbs during level walking in children with spastic HCP. A total of 12 children with spastic HCP and 12 healthy controls walked at a self-selected speed in a gait laboratory while their kinematic and forceplate data were measured and analyzed during loading response, midstance, terminal stance, and preswing. The altered joint kinematics and kinetics in the nonaffected limb in the HCP group appeared to be mainly a compensatory strategy to minimize the bilateral asymmetry in leg stiffness during the double-limb support phase and joint stiffness during the entire stance phase. The current results suggest that therapeutic planning and decision-making for children with HCP should consider not only the mechanics of the affected side but also the control of the nonaffected side.
Topics: Adolescent; Case-Control Studies; Cerebral Palsy; Child; Gait; Hemiplegia; Humans; Joints; Leg
PubMed: 32086827
DOI: 10.1002/jor.24635 -
PloS One 2022Even though running enjoys growing popularity, the effects of fatigue on the running kinematics of novices have rarely been studied. This is surprising, given the risk...
Even though running enjoys growing popularity, the effects of fatigue on the running kinematics of novices have rarely been studied. This is surprising, given the risk of running-related injuries when detrimental movement patterns are adopted. Therefore, the goal of the present study was to characterize the effects of fatigue induced by a high-intensity running protocol on spatiotemporal and stiffness parameters as well as on joint kinematics and center of mass (CoM) motion in novice runners. 14 participants performed a standardized treadmill familiarization and ran at 13 km/h until voluntary exhaustion. Kinematics were captured using a 3D motion capture system. Spatiotemporal and stiffness parameters as well as the range of motion (RoM) of the joints and CoM were compared by use of paired t-tests. Time series of the joint angles and CoM motion were analyzed by the statistical parametric mapping method. The results revealed that novice runners did not change spatiotemporal or stiffness parameters, but showed adaptations in joint kinematics, e.g. decreased dorsiflexion and increased pronation in the ankle joint during the swing phase. The findings of this study underline the importance of strengthening the ankle joint to prevent excessive pronation and increase its stability in novice runners.
Topics: Ankle Joint; Biomechanical Phenomena; Humans; Leg; Pronation; Range of Motion, Articular
PubMed: 35363776
DOI: 10.1371/journal.pone.0265550 -
PloS One 2015Individual joint deviations are often identified in the analysis of cerebral palsy (CP) gait. However, knowledge is limited as to how these deviations affect the control...
Individual joint deviations are often identified in the analysis of cerebral palsy (CP) gait. However, knowledge is limited as to how these deviations affect the control of the locomotor system as a whole when striving to meet the demands of walking. The current study aimed to bridge the gap by describing the control of the locomotor system in children with diplegic CP in terms of their leg stiffness, both skeletal and muscular components, and associated joint stiffness during gait. Twelve children with spastic diplegia CP and 12 healthy controls walked at a self-selected pace in a gait laboratory while their kinematic and forceplate data were measured and analyzed during loading response, mid-stance, terminal stance and pre-swing. For calculating the leg stiffness, each of the lower limbs was modeled as a non-linear spring, connecting the hip joint center and the corresponding center of pressure, with varying stiffness that was calculated as the slope (gradient) of the axial force vs. the deformation curve. The leg stiffness was further decomposed into skeletal and muscular components considering the alignment of the lower limb. The ankle, knee and hip of the limb were modeled as revolute joints with torsional springs whose stiffness was calculated as the slope of the moment vs. the angle curve of the joint. Independent t-tests were performed for between-group comparisons of all the variables. The CP group significantly decreased the leg stiffness but increased the joint stiffness during stance phase, except during terminal stance where the leg stiffness was increased. They appeared to rely more on muscular contributions to achieve the required leg stiffness, increasing the muscular demands in maintaining the body posture against collapse. Leg stiffness plays a critical role in modulating the kinematics and kinetics of the locomotor system during gait in the diplegic CP.
Topics: Biomechanical Phenomena; Case-Control Studies; Cerebral Palsy; Child; Gait; Humans; Joints; Leg; Mechanical Phenomena; Muscles; Walking
PubMed: 26629700
DOI: 10.1371/journal.pone.0143967 -
Orthopaedics & Traumatology, Surgery &... Feb 2016High-energy injuries to the wrist gather complex fractures of the distal radius, radiocarpal dislocations, perilunate dislocations, and other intracarpal dislocations.... (Review)
Review
High-energy injuries to the wrist gather complex fractures of the distal radius, radiocarpal dislocations, perilunate dislocations, and other intracarpal dislocations. Depending on the energy of the injury and the position of the wrist at the time of impact, the patient, often a young male with a high functional demand, presents one of these injuries associating fracture(s) and ligament injury. The trauma is often bilateral, with proximal lesions (elbow) very often associated with contusion or compression of the median nerve. Diagnosis is confirmed by wrist X-rays, which are sufficient to determine treatment for radiocarpal and perilunate dislocations. In cases of distal radius fractures or other intracarpal dislocations, a preoperative CT is necessary. Reduction of the dislocation and relief of neurovascular compression are performed immediately. The final treatment of each lesion (bone fixation, ligament repair) can be undertaken simultaneously or delayed, depending on the patient and the lesions. Cartilage lesions, resulting from the high-energy injury, can be estimated using arthroscopy but cannot be repaired and determine the prognosis. The surgeon's objective is to restore joint congruence, which does not prevent stiffness, the main complication of these rare injuries, which the surgeon must know how to recognize and treat.
Topics: Arthroscopy; Carpal Joints; Elbow Joint; Humans; Joint Dislocations; Radiography; Radius Fractures; Wrist Injuries; Wrist Joint
PubMed: 26782706
DOI: 10.1016/j.otsr.2015.05.009 -
International Journal of Environmental... Sep 2021Acupuncture can improve explosive force production and affect joint stiffness by affecting muscle activation levels. This study aims to explore the effects of true... (Randomized Controlled Trial)
Randomized Controlled Trial
Acupuncture can improve explosive force production and affect joint stiffness by affecting muscle activation levels. This study aims to explore the effects of true acupuncture (TA) compared with sham acupuncture (SA) on the explosive force production and stiffness of the knee joint in healthy male subjects. Twenty subjects were randomly divided into the TA group ( = 10) and SA group ( = 10) to complete isokinetic movement of the right knee joint at a speed of 240°/s before and after acupuncture. Futu (ST32), Liangqiu (ST34), Zusanli (ST36), Xuehai (SP10), and Chengshan (BL57) were selected for acupuncture. The intervention of SA is that needles with a blunt tip were pushed against the skin, giving an illusion of insertion. The results showed that acupuncture and the intervention time had a significant interaction effect on knee joint explosive force and joint stiffness ( < 0.05). The average maximum (max) torque, average work, average power, average peak power and total work of the TA group increased significantly after acupuncture ( < 0.05), while the SA group did not ( > 0.05). Therefore, true acupuncture can immediately improve the explosive force and joint stiffness of the male knee joint by inducing post-activation potentiation (PAP) and/or De-Qi.
Topics: Acupuncture Therapy; Humans; Knee Joint; Male; Osteoarthritis, Knee
PubMed: 34574441
DOI: 10.3390/ijerph18189518 -
Technology and Health Care : Official... 2022Children with Down syndrome (DS) have critical biomechanical impairments such as increased ligamentous laxity, muscle hypotonia, and dysfunctional motor coordination,...
BACKGROUND
Children with Down syndrome (DS) have critical biomechanical impairments such as increased ligamentous laxity, muscle hypotonia, and dysfunctional motor coordination, which makes performing everyday tasks challenging.
OBJECTIVE
The purpose of the study was to explore the differences in the vertical joint stiffness, plantar force, and range of motion during drop landing for DS and age-matched typically developing children.
METHODS
Six young male children with DS and age-matched seven healthy typically developing children (TD) assessed joint strength using an isokinetic dynamometer and performed five trials of single-leg drop jump using force platform and motion capture system.
RESULTS
The peak vertical ground reaction force (VGRF), Range of motion (ROM), joint stiffness, and joint strength of lower limb were calculated and compared across DS and TD groups. The results revealed a significantly larger peak VGRF [z=-2.857, p< 0.001] values for the DS group compared to the TD groups. The results of Spearman's correlation analysis showed a negative correlation between hip joint stiffness and knee joint ROM [r=-0.886, p< 0.05] and ankle joint stiffness and knee joint ROM [r=-0.829, p< 0.05] for DS.
CONCLUSIONS
The abnormal movements observed among DS was not due to the difference in stiffness of the lower extremity but due to the utilization of different landing mechanisms with changes in ROM.
Topics: Ankle Joint; Biomechanical Phenomena; Child; Down Syndrome; Humans; Knee Joint; Male; Range of Motion, Articular
PubMed: 35124613
DOI: 10.3233/THC-THC228035 -
Journal of Neuroengineering and... Aug 2021User preference has the potential to facilitate the design, control, and prescription of prostheses, but we do not yet understand which physiological factors drive...
BACKGROUND
User preference has the potential to facilitate the design, control, and prescription of prostheses, but we do not yet understand which physiological factors drive preference, or if preference is associated with clinical benefits.
METHODS
Subjects with unilateral below-knee amputation walked on a custom variable-stiffness prosthetic ankle and manipulated a dial to determine their preferred prosthetic ankle stiffness at three walking speeds. We evaluated anthropomorphic, metabolic, biomechanical, and performance-based descriptors at stiffness levels surrounding each subject's preferred stiffness.
RESULTS
Subjects preferred lower stiffness values at their self-selected treadmill walking speed, and elected to walk faster overground with ankle stiffness at or above their preferred stiffness. Preferred stiffness maximized the kinematic symmetry between prosthetic and unaffected joints, but was not significantly correlated with body mass or metabolic rate.
CONCLUSION
These results imply that some physiological factors are weighted more heavily when determining preferred stiffness, and that preference may be associated with clinically relevant improvements in gait.
Topics: Ankle; Ankle Joint; Artificial Limbs; Biomechanical Phenomena; Gait; Humans; Patient Preference; Prosthesis Design; Walking
PubMed: 34433472
DOI: 10.1186/s12984-021-00916-1