Gastrocnemius tightness on joint angle and work of lower extremity during gait

Background

Muscular tightness is a common clinical musculoskeletal disorder and is regarded as a predisposing factor for muscle injuries. In this study, a two-way mixed design ANOVA was applied to investigate the effects of the gastrocnemius tightness on the joint angle and joint work during walking.

Methods

Twenty-two patients with muscular tightness of gastrocnemius muscle (<12° of ankle dorsiflexion with knee extended) and 22 age- and gender-matched subjects with normal gastrocnemius flexibility (>15° of ankle dorsiflexion with knee extended) participated in this study. The joint angle and work at hip, knee, and ankle joints during the stance phase were analyzed at two preset cadences of 100 steps/min and 140 steps/min.

Findings

Significantly greater flexion angles at hip (P = 0.025) and knee (P = 0.001) were found in the tightness group at the time of maximal ankle dorsiflexion. Significantly less work generation at knee (P = 0.034) and greater work absorption at ankle (P = 0.024) were detected in the tightness group.

Interpretation

The subjects with gastrocnemius tightness revealed a compensatory gait pattern, which included the changes in the joint angles and associated work productions. The potential disturbance of the knee control and strain injuries of plantar flexors might be crucial in the clinical considerations for subjects with gastrocnemius tightness.     

The impact of simulated ankle plantarflexion contracture on the knee joint during stance phase of gait: A within-subject study

Background

Ankle plantarflexion contractures are common in adults with neurological disorders and known to cause secondary gait deviations. However, their impact on the knee joint is not fully understood. The aims of this study are to describe the effect of simulated plantarflexion contractures on knee biomechanics during the stance phase and on the spatiotemporal characteristics of gait.

Methods

Mild (10–degree plantarflexion) and severe (20–degree plantarflexion) ankle contractures were simulated in thirteen able-bodied adults using an ankle-foot-orthosis. A no contracture condition was compared with two simulated contracture conditions.

Findings

There was an increase in knee extension, sometimes resulting in hyperextension, throughout stance for the two contracture conditions compared to the no contracture condition (mean increase in knee extension ranged from 5° to 9°; 95% CI 0° to 17°). At the same time, there were reductions in extension moment and power generation at the knee. Simulated plantarflexion contractures also reduced gait velocity, bilateral step length and cadence. All these changes were more pronounced in the severe contracture condition than mild contracture condition. While the majority of participants adopted a foot-flat pattern on landing and exhibited an increase in knee extension during stance, two participants used a toe-walking pattern and exhibited an increase in knee flexion.

Interpretation

Ankle plantarflexion contractures are associated with an increase in knee extension during stance phase. However, some people with simulated ankle contractures may walk with an increase in knee flexion instead. Ankle plantarflexion contractures also adversely affect gait velocity, step length and cadence.     

Lower extremity kinetics during stair ambulation in patients with and without patellofemoral pain

Objective. To compare lower extremity kinetics during stair ascent and descent in subjects with and without patellofemoral pain.

Design. A cross-sectional study utilizing a control group.

Background. The patellofemoral joint reaction force (the resultant force between the quadriceps muscle force and patellar ligament force) increases with quadriceps force and knee flexion angle. Consequently, patients with patellofemoral pain may employ compensatory strategies to minimize pain and reduce patellofemoral joint reaction forces during activity.

Methods. 10 individuals with a diagnosis of patellofemoral pain and 10 individuals without pain participated. Subject groups were matched on sex, age, height, and body mass. Anthropometric data, three dimensional kinematics, and ground reaction forces were used to calculate lower extremity sagittal plane moments (inverse dynamics) while subjects ascended and descended stairs at a self-selected pace. Differences in kinetic variables between groups were assessed using 2×2 (group × stair condition) analysis of variance.

Results. Subjects with patellofemoral pain had decreased peak knee extensor moments during stair ascent and descent. There were no group differences in peak hip, ankle, or support moments, however, subjects with patellofemoral pain had decreased cadence (descent) compared to controls.

Conclusion. Subjects with patellofemoral pain had reduced peak knee extensor moments, suggesting that quadriceps avoidance was employed to reduce patellofemoral joint reaction forces. The lack of group differences in peak moments at the hip and ankle suggests that secondary compensation did not occur exclusively at the hip or ankle in this group of subjects with patellofemoral pain.Relevance statement

Because stair ambulation is often used to evaluate the reproducibility of symptoms and to identify abnormal movement patterns indicative of patellofemoral pain, knowledge of lower extremity mechanics during stair negotiation is necessary to better characterize compensatory behavior in this population.     

Foot orthotics affect lower extremity kinematics and kinetics during running

OBJECTIVE: To quantify the effects of posting and custom-molding of foot orthotics on lower extremity kinematics and kinetics during running. DESIGN: Repeated measures.Background. Several kinematic and kinetic factors have been suggested to increase a runner's risk for injuries. It has been speculated that foot orthotics can be used to reduce injury related complaints or even prevent running injuries by affecting these factors. METHODS: Twenty one volunteers participated in this study. Kinematic and kinetic variables obtained during overground running for medial posting, custom-molding, and the combination of medial posting and custom-molding of foot orthotics were compared to a control condition. Repeated measures ANOVA and student t-tests were used to detect significant differences (alpha=0.05). RESULTS: Posting of foot orthotics reduced maximum foot eversion and ankle inversion moment and increased vertical loading rate and maximum knee external rotation moment (P<0.05). Molding and posting and molding reduced vertical loading rate and ankle inversion moment and increased maximum foot inversion and maximum knee external rotation moment (P<0.05). CONCLUSIONS: The effects of posting and molding of foot orthotics are extremely different and when combining posting and molding, the effects of molding appear to be dominant. It yet remains to be determined whether posting or molding is more beneficial with respect to overuse running injuries. RELEVANCE: The potential of foot orthotics for reducing pain and injuries is convincing. The current study provides valuable information about the role of specific structural components of foot orthotics and contributes to the knowledge about the mechanism underlying the effect of foot orthotics in running.     

Male and female gluteal muscle activity and lower extremity kinematics during running

Background

Patellofemoral pain is one of the most common lower extremity overuse injuries in runners and is significantly more common in females. This study evaluated differences in the timing and magnitude of gluteal muscle activity as well as hip and knee joint frontal and transverse plane kinematics between male and female runners in the context of this gender bias.

Methods

Twenty healthy male and 20 healthy female runners were participants. Three-dimensional lower extremity kinematics, and gluteus medius and gluteus maximus muscle activation were recorded using motion analysis and electromyography as subjects ran at 3.7 m/s (+/−5%). Comparisons of hip and knee joint kinematic and gluteus muscle activation data were made using independent t-tests (α = 0.05).

Findings

Females ran with 40% greater peak gluteus maximus activation level (P = 0.028, effect size = 0.79) and 53% greater average activation level (P = 0.013, effect size = 0.93) than males. Female runners also displayed greater hip adduction (P = .001, effect size = 1.20) and knee abduction (P = 0.011, effect size = 0.87) angles at initial contact, greater hip adduction at peak vertical ground reaction force (P < 0.001, effect size = 1.31), and less knee internal rotation excursion than males (P = 0.035, effect size = 0.71).

Interpretation

Greater gluteus maximus activation levels during running may predispose females to earlier gluteus maximus fatigue, promoting altered lower extremity running kinematics thought to be associated with the etiology of patellofemoral pain. Gender differences in transverse and frontal plane hip and knee kinematics observed in this study may also contribute to the gender bias for patellofemoral pain among females.     

Gastrocnemius inflexibility on foot progression angle and ankle kinetics during walking

Background

Gastrocnemius inflexibility is a major problem in many orthopedic and neurological patients. Clinically, inflexible gastrocnemius muscles interfere with the performance of functional abilities and associate with many overuse injuries of the lower extremity. The purpose of this study was to investigate the effects of the gastrocnemius inflexibility on the foot progression angle and ankle kinetics during walking.

Methods

There were 50 subjects, 23 patients with the inflexible gastrocnemius and 27 normal subjects, included in this investigation. Participants were asked to walk at two preset cadences of 100 steps/min and 140 steps/min. Data were collected from a motion analysis system and force plates. Kinematic and kinetic variables of gait were computed and analyzed.

Findings

Compared with the control group, greater toe-out foot progression angle (P = 0.001, effect size = 0.314) and knee external rotation (P = 0.008, effect size = 0.136) were found in the inflexible group during stance phase. Furthermore, significant greater plantarflexion moment (P = 0.032, effect size = 0.093) and medial ground reaction force (P = 0.009, effect size = 0.135) during midstance were discovered in the inflexible group.

Interpretation

The present results indicate that gastrocnemius inflexibility might bring about the changes in the joint angles, ankle moments and ground reaction forces. The abnormal joint alignment in the lower extremities and greater force upon joint tissue might be significant for the clinical considerations on soft tissue injuries for the patients with inflexible gastrocnemius muscles.     

Effects of supramalleolar osteotomies for ankle osteoarthritis on foot kinematics and lower leg muscle activation during walking

Background

Early stages of asymmetric ankle osteoarthritis can be treated by joint preserving supramalleolar osteotomies that surgically realign the ankle and unload degenerated cartilage. While studies have already shown pain relief and functional improvements, the effects on gait biomechanics are largely unknown. This study investigated patients' gait pattern after supramalleolar osteotomies by focusing on foot kinematics and lower leg muscle activation.

Methods

An instrumented three-dimensional gait analysis with simultaneous electromyography of gastrocnemius medialis and lateralis, soleus, peroneus longus, and tibialis anterior muscles was performed on 12 patients with ankle osteoarthritis, seven of which were followed up 12–18 months postoperatively. Additionally, seven different long-term follow-up patients (8–9 years postoperatively) and 15 healthy control subjects were measured. The waveforms of the foot kinematics and muscle activation were analyzed using principal component analysis.

Findings

Compared to healthy controls, principal component scores that affected the sagittal range of motion of the hindfoot and hallux were lower in all patient groups, while scores that affected the timing of the peaks in the sagittal forefoot motion were mainly altered in short-term follow-up patients. Lower principal component scores in patients with ankle osteoarthritis and short-term follow-up patients resulted in a less pronounced peak activation of gastrocnemius medialis and soleus.

Interpretation

Both postoperative patient groups showed similar adaptations in their gait pattern as those observed in patients with ankle osteoarthritis. These changes are probably related to the lower ankle mobility. However, the reduced mobility seems to affect the patients' well-being less than a painful joint.     

Knee joint kinematics, kinetics and muscle co-contraction in knee osteoarthritis patient gait

Background

Compared to matched controls, knee osteoarthritis patients walk with altered, kinematics, kinetics and muscle activity. Studies of osteoarthritis patient gait have focused on individual measures, and findings from these studies differ due to differences in patient levels of disability and age. Therefore, aims of this study were to examine kinematic, kinetic and muscle co-contraction gait variables within a single osteoarthritis patient group, and to determine if alterations in these variables are related to pain, symptom and function measures.

Methods

Thirty asymptomatic controls and 54 patients with radiographic evidence of knee osteoarthritis participated. Self-perceived measures of pain and symptoms, and gait (knee joint angles, moments and muscle co-contraction) were analysed and compared.

Findings

Osteoarthritis patients had greater self-perceived pain and symptoms on the questionnaires. Gait differences in the knee osteoarthritis patients were greater knee flexion at heel strike and during early stance along with reductions in the peak external knee extension moment in late stance. Co-contraction ratios highlighted greater lateral muscle activation in osteoarthritis patients, which were correlated with the magnitude of their adduction moments. Larger adduction moments were related to lower self-perceived pain and symptoms.

Interpretation

Osteoarthritis patients use predominantly lateral muscle activation during stance which may aid in stabilising the external knee adduction moment. Kinematic alterations in knee osteoarthritis patient gait occur without alterations in knee joint moments. Our results also suggest that adduction moments are lowered to reduce the patients’ pain and symptoms.     

Gender differences in lower extremity kinematics,kinetics and energy absorption during landing

OBJECTIVE: To determine whether gender differences exist in lower extremity joint motions and energy absorption landing strategies between age and skill matched recreational athletes. DESIGN: Mixed factor, repeated measures design. BACKGROUND: Compared to males, females execute high demand activities in a more erect posture potentially predisposing the anterior cruciate ligament to greater loads and injury. The preferred energy absorption strategy may provide insight for this performance difference. METHODS: Inverse dynamic solutions estimated lower extremity joint kinematics, kinetics and energetic profiles for twelve males and nine females performing a 60 cm drop landing. RESULTS: Females demonstrated a more erect landing posture and utilized greater hip and ankle joint range of motions and maximum joint angular velocities compared to males. Females also exhibited greater energy absorption and peak powers from the knee extensors and ankle plantar-flexors compared to the males. Examinations of the energy absorption contributions revealed that the knee was the primary shock absorber for both genders, whereas the ankle plantar-flexors muscles was the second largest contributor to energy absorption for the females and the hip extensors muscles for the males. CONCLUSIONS: Females may choose to land in a more erect posture to maximize the energy absorption from the joints most proximal to ground contact. RELEVANCE: Females may be at a greater risk to anterior cruciate ligament injury during landing due to their energy absorption strategy.     

The effect of custom-made braces for the ankle and hindfoot on ankle and foot kinematics and ground reaction forces

OBJECTIVE: To assess the effects on gait of custom-made polypropylene orthoses: ankle-foot orthosis (AFO), rigid hindfoot orthosis (HFO-R), and articulated hindfoot orthosis (HFO-A). DESIGN: Experimental assessment. SETTING: Institutional practice, motion analysis laboratory. PARTICIPANTS: Twenty asymptomatic normative subjects. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Three-dimensional kinematics, ground reaction force, and time-related factors in 4 conditions: shoe only, and shod with the AFO, HFO-R, and HFO-A. RESULTS: The AFO and HFO-R limited sagittal and coronal plane ankle-hindfoot motion. The HFO-A limited hindfoot coronal motion while allowing normal sagittal motion. At the midfoot, the AFO and HFO-A limited transverse motion, but the HFO-A also limited sagittal and coronal motion. Use of the HFO-R resulted in exaggerated midfoot sagittal and coronal motion. Braces that limited motion to a greater degree were associated with more atypical kinetic variables, indicative of less dynamic gait. The HFO-A resulted in ground reaction forces most similar to unbraced conditions. CONCLUSIONS: Alteration in gait was affected by orthosis design. Orthoses with a rigid component crossing a joint restricted motion at that joint, but potentially compromised typical gait kinetic factors. For immobilizing the hindfoot, the HFO-A may be more comfortable and still provide more stability than the HFO-R or AFO.     

踝足矫形器对偏瘫患者步行速度的影响

目的：了解踝足矫形器（ａｎｋｌｅ－ｆｏｏｔ ｏｒｔｈｏｓｉｓ,ＡＦＯ）对偏瘫患者步行速度的影响。方法：３０例偏瘫患者在步态分析实验分别穿鞋和赤足行走两次,用摄像机录下患者的步行过程,用运动动态分析软件进行数据分析。结果：不穿ＡＦＯ者穿鞋和赤足的步行速度无显著性差异（Ｐ〉０．０５）;不穿ＡＦＯ者穿鞋与穿ＡＦＯ者穿鞋加ＡＦＯ时步行速度无显著性差异（Ｐ〉０．０５）;不穿ＡＦＯ者与穿ＡＦＯ者赤足时步行速度     

Effect of trunk inclination on lower limb joint and lumbar moments in able men during the stance phase of gait

Background

Though the effect of imposed trunk posture affects walking patterns little is known about the effect of natural orientation of the trunk on gait. The objectives of this study are to test if the lower limb joint and thoraco-lumbar moments are similar in subjects who maintain an average natural forward or backward trunk inclination during gait and verify if the lower limbs are equally affected.

Methods

Twenty-five young men were divided according to their natural backward or forward trunk inclination during level walking. Ankle, knee, hip and thoraco-lumbar moments were calculated by an inverse dynamic approach for the two limbs. A two-way ANOVA was performed on peak lower limb moments. A one-way ANOVA was performed on thoraco-lumbar peak moments.

Findings

There was a main effect for both trunk inclinations and lower limb sides but no interaction. For the forward leaners, the duration of hip extension moment was longer (P < 0.001) while the hip flexion moment was 1.3 times smaller (P < 0.001). Differences between the lower limb sides were noted in all joints but at push-off of the stance phase only. The two thoraco-lumbar extension moments were, respectively, 1.4 times higher for the forward leaners while the two flexion moments were approximately 1.4 times higher for the backward leaners.

Interpretations

The backward leaners propel themselves with a strong hip flexor activity at push-off while the forward leaners use their hip muscles throughout stance. These results support the idea that trunk inclinations and moment variations are associated with the type of walking patterns.     

The relationship between knee joint loading rate during walking and degenerative changes on magnetic resonance imaging

Background

While animal study and cadaveric study have demonstrated an association between knee joint loading rate and joint degeneration, the relationship between knee joint loading rate during walking and osteoarthritis has not yet been sufficiently studied in humans.

Methods

Twenty-eight participants (14 transfemoral amputees and 14 age and body mass matched controls) underwent knee MRI with subsequent assessment using the semiquantitative Whole-Organ Magnetic Resonance Image Score. Each subject also underwent gait analysis in order to determine knee adduction moment loading rate, peak, and impulse and an exploratory measure, knee adduction moment rate ∗ magnitude.

Findings

Significant correlations were found between medial tibiofemoral joint degeneration and knee adduction moment peak (slope = 0.42 [SE 0.20]; P = .037), loading rate (slope = 12.3 [SE 3.2]; P = .0004), and rate ∗ magnitude (slope = 437 [SE 100]; P < .0001). These relationships continued to be significant after adjusting for body mass or subject type. The relationship between medial knee semiquantitative MRI score and knee adduction moment loading rate and rate ∗ magnitude continued to be significant even after adjusting for peak moment (P < .0001), however, the relationship between medial knee semiquantitative MRI score and peak moment was no longer significant after adjusting for either loading rate or rate ∗ magnitude (P > .2 in both cases).

Interpretation

This study suggests an independent relationship between knee adduction moment loading rate and medial tibiofemoral joint degeneration. Our results support the hypothesis that rate of loading, represented by the knee adduction moment loading rate, is strongly associated with medial tibiofemoral joint degeneration independent of knee adduction moment peak and impulse.     

Effects of toning shoes on lower extremity gait biomechanics

Background

The Reebok Easy Tone shoe concept was developed to induce instability during walking and standing with the primary purpose of increasing muscle activity of the lower extremity muscles. To the authors' knowledge, no scientific work has been published, which analyzed neuromuscular and biomechanical effects when walking and standing with Reebok Easy Tone shoes. Therefore, the purpose of this study was to investigate the immediate effects of using such footwear on gait biomechanics for the lower extremity in healthy participants.

Methods

Five healthy female and seven healthy male participants volunteered to participate in this study. During quiet standing, centre of pressure excursion was determined. 3D gait analyses were performed with simultaneously collecting surface electromyography data of the leg muscles when walking with regular shoes and with Reebok Easy Tone shoes.

Findings

Centre of pressure excursion did not show any significant differences. For walking, only slight differences were found in kinematics and kinetics. When walking with Reebok Easy Tone shoes, the first vertical peak of the ground reaction force was significantly increased as well as the maximum plantarflexion moment during initial contact and loading response. Mean muscle activation for vastus medialis and lateralis showed an increase during the second half of stance, but failed to reach significance.

Interpretation

Results of this study did not show any increased instability during standing and only a slight increase of vastii activity during stance. Thus, the marketing claims that “toning shoes” could serve as a sort of training devices for lower limb muscles during walking, cannot be supported.     

The effect of lower extremity fatigue on shock attenuation during single-leg landing

BACKGROUND: The forces that are imposed on the body due to landings must be attenuated primarily in the lower extremity. Muscles assist in the absorption of these forces, and it has been shown that a fatigued muscle decreases the body's ability to attenuate shock from running. The purpose of the study was to determine the effect of lower extremity fatigue on shock attenuation and joint mechanics during a single-leg drop landing. METHODS: Ten active male participants were recruited (eight used for analysis). Each participant took part in a fatigue landing protocol. This protocol included cycles of a drop landing, a maximal countermovement jump, and five squats, repeated until exhaustion. Accelerometers attached to the skin measured tibia and head accelerations. Lower extremity kinematics were collected using an electromagnetic tracking system and kinetics were collected using a forceplate. A repeated-measures ANOVA (P<0.05) was performed on each of the dependent variables across the cycles of the fatigue protocol. FINDINGS: Fatigue was induced, however there was no significant change in shock attenuation throughout the body. Hip and knee flexion increased and ankle plantarflexion decreased at touchdown with fatigue. Hip joint work increased and ankle work decreased. INTERPRETATION: This change in work distribution is thought to be a compensatory response to utilize the larger hip extensors that are better suited to absorb the mechanical energy of the impact. The results suggested that the lower extremity is able to adapt to fatigue though altering kinematics at impact and redistributing work to larger proximal muscles.     

The effect of electromagnetic navigation in total knee arthroplasty on knee kinematics during functional activities using flexible electrogoniometry

Background

Navigated total knee arthroplasty has been shown to increase accuracy in post operative implant alignment. By contrast navigated total knee arthroplasty has not shown significant functional improvements to date, when compared with conventional surgery using subjective clinical questionnaire scores. The aim of this study was to compare the knee joint kinematics measured during functional activities using electrogoniometry 12 months after total knee arthroplasty in randomised navigated and conventional total knee arthroplasty groups.

Methods

The study design was a double blinded, randomised, prospective, controlled trial. The patients were randomised into 2 surgical groups (n = 102 navigated group, n = 98 conventional group; mean age navigated = 67, conventional = 67). Flexible electrogoniometry was used to measure patient's knee kinematics with respect to time during 12 functional activities.

Findings

No significant difference was found in terms of the maximum, minimum and excursion knee joint angle during any of the functional activities. However there was a statistically significant improvement in the level and slope gait cycle at the pre swing phase in the navigated group.

Interpretation

There were minimal functional improvements in the navigated total knee arthroplasty group 12 months after surgery. However, these are unlikely to have a significant effect on daily activity for the navigated group.     

制动对兔比目鱼肌和腓肠肌形态的影响

目的：比较４周的制动对兔比目鱼肌和腓肠湿重及两种肌纤维截面面积的影响,并分析这种差异与制动时间的关系。方法：将试验动物一侧后肢制动４周后,分别测量两种肌 肉的湿重;将肌肉作恒冷冻横切片,肌球蛋白ＡＴＰ酶组织化学染色（ｐＨ９．４）,测量两 种肌纤维的截面面积。结果：与对照组相比,制动４周后两种肌肉的湿重均有显著性下降（Ｐ〈０．０１）,比目鱼肌湿重下降３１％,腓肠肌湿重下降２９％。比目鱼肌中Ⅰ型纤维的