Knee extensor and flexor dominant gait patterns increase the knee frontal plane moment during walking

Gait variability and biomechanical distinctions in knee osteoarthritis: Insights from a 3D analysis in an adult elderly cohort

Background

This study employs 3D gait analysis to investigate normal gait patterns in individuals afflicted with knee Osteoarthritis (OA). Focusing on the adult osteoarthritic population, the research aims to establish reference values for joint angles, temporospatial parameters, Gait Profile Score (GPS), and Movement Analysis Profile (MAP) collected concurrently along a standardized walking path. Furthermore, the study delves into potential variations linked to gender and OA severity, comparing gait parameters between male and female participants and among individuals with grade 3 and grade 4 OA.

Method

The study involved 34 adults with a mean age of 68.6 ± 5.75 years, all experiencing OA knees and awaiting Total Knee Arthroplasty (TKA). Utilizing Qualisys Motion capture system, 3D gait analysis was conducted. Data were processed through Visual 3D C-Motion Software.

Results

Gait analysis revealed noteworthy differences between genders for various parameters, including stance time, GPS, MAP of the hip, and joint angle for the sagittal plane (ankle), coronal plane (knee), and transverse plane (hip and knee). Moreover, significant differences were observed between grade 3 and grade 4 OA knees in MAP and for the transverse plane joint angle (ankle).

Conclusion

This gait analysis study sheds light on distinctive gait patterns in the adult osteoarthritic population. The identified variations in temporospatial parameters, joint angles, GPS, and MAP provide valuable reference values for individuals suffering from knee OA. The observed differences between genders and across different OA severity grades emphasize the need for personalized approaches in managing knee OA and planning interventions like TKA.

Frontal plane knee moment in clinical gait analysis: A systematic review on the effect of kinematic gait changes

INTRODUCTION

The frontal plane knee moment (KAM1 and KAM2) derived from non-invasive three-dimensional gait analysis is a surrogate measure for knee joint load and of great interest in clinical and research settings. Many aspects can influence this measure either unintentionally or purposely in order to reduce the knee joint load to relieve symptoms and pain. All these aspects must be known when conducting a study or interpreting gait data for clinical decision-making.

METHODS

This systematic review was registered with PROSPERO (CRD42020187038). Pubmed and Web of Science were searched for peer-reviewed, original research articles in which unshod three-dimensional gait analysis was undertaken and KAM1 and KAM2 were included as an outcome variable. Two reviewers independently screened articles for inclusion, extracted data and performed a methodological quality assessment using Downs and Black checklist.

RESULTS

In total, 42 studies were included. Based on the independent variable investigated, these studies were divided into three groups: 1) gait modifications, 2) individual characteristics and 3) idiopathic orthopedic deformities. Among others, fast walking speeds (1) were found to increase KAM1; There were no sex-related differences (2) and genu valgum (3) reduces KAM1 and KAM2.

CONCLUSION

While consistent use of terminology and reporting of KAM is required for meta-analysis, this review indicates that gait modifications (speed, trunk lean, step width), individual characteristics (body weight, age) and idiopathic orthopedic deformities (femoral or tibial torsion, genu valgum/varum) influence KAM magnitudes during walking. These factors should be considered by researchers when designing studies (especially of longitudinal design) or by clinicians when interpreting data for surgical and therapeutic decision-making.

Change in Bone Mineral Density in Stroke Patients with Osteoporosis or Osteopenia

We aimed to investigate the correlation between changes in bone mineral density (BMD) of the lumbar spine (LS) and femoral neck (FN) and osteoporosis-related factors in stroke patients with osteoporosis or osteopenia, and we suggest the need for active rehabilitation treatment. This study included 63 osteoporosis and 34 osteopenia patients who underwent a BMD test following primary stroke onset. The osteoporosis group was followed up with a BMD test after 12 months of bisphosphonate treatment, and the osteopenia group was followed up without medication. The correlation between BMD changes and functional factors was analyzed, biochemical markers were measured, and hematology tests were performed. In the osteoporosis group, a significant increase was observed in LS BMD (p < 0.05), and in the osteopenia group, there was a significant decrease in FN BMD (p < 0.05). The group with a functional ambulatory category of 1 or more showed a significant improvement in BMD (p < 0.05). Comparative analysis was performed on various indicators, but no significant correlation was found between any variable. In stroke patients with osteoporosis or osteopenia, early appropriate drug treatment is important to prevent bone loss and reduce the risk of fractures, and comprehensive rehabilitation treatment, such as appropriate education and training to prevent falls, is essential.

Gait Adaptations at 8 Years After Reconstruction of Unilateral Isolated and Combined Posterior Cruciate Ligament Injuries

BACKGROUND

It remains unclear how posterior cruciate ligament (PCL) reconstruction influences long-term lower extremity joint biomechanics.

PURPOSE

To determine whether patients who underwent PCL reconstruction exhibited long-term alterations in lower limb gait mechanics.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 26 patients underwent gait analyses at 8.2 ± 2.6 years after primary unilateral PCL reconstruction. Sex- and age-matched healthy controls were analyzed for comparison. Gait data were collected using motion capture and force plates. Hip, knee, and ankle angles and moments were compared during initial contact, early stance, and late stance for the reconstructed and uninjured contralateral limbs of patients who underwent PCL reconstruction (PCL group) as well as the limbs of healthy control participants (CON group).

RESULTS

No side-to-side kinematic differences were noted between the reconstructed and contralateral limbs of the PCL group; some trivial differences were noted in knee and hip moments. However, major differences between the PCL and CON groups occurred at the knee. Reconstructed and contralateral limbs of the PCL group exhibited larger knee flexion angles during initial contact (Δ = 7.0° [P < .001] and Δ = 6.9° [P < .001], respectively), early stance (Δ = 5.8° [P = .003] and Δ = 6.7° [P < .001], respectively), and late stance (Δ = 7.9° [P < .001] and Δ = 8.0° [P < .001], respectively) compared with the CON group. During early stance, contralateral limbs of the PCL group displayed larger knee flexion moments (Δ = 0.20 N·m/kg; P = .014) compared with the CON group, and both reconstructed (Δ = 0.05 N·m/kg; P = .027) and contralateral (Δ = 0.07 N·m/kg; P = .001) limbs of the PCL group exhibited larger knee external rotation moments compared with the CON group. During late stance, reconstructed and contralateral limbs of the PCL group exhibited smaller knee extension moments (Δ = 0.24 N·m/kg [P < .001] and Δ = 0.26 N·m/kg [P < .001], respectively) and knee internal rotation moments (Δ = 0.06 N·m/kg [P < .001] and Δ = 0.06 N·m/kg [P < .001], respectively) compared with the CON group. No discrepancies were observed at the hip; minimal differences were noted in sagittal-plane ankle mechanics.

CONCLUSION

Patients who underwent PCL reconstruction generally exhibited bilateral gait symmetry at 8 years after surgery. However, they exhibited important biomechanical deviations in both knees compared with healthy controls. These modifications likely reflect adaptive gait strategies to protect the PCL after reconstruction.

CLINICAL RELEVANCE

Long-term follow-up analyses of patients who underwent PCL reconstruction should not use the uninjured contralateral limb as a "healthy" reference, as it also exhibits mechanical differences compared with controls. Results could inform the development of neuromuscular and strength training programs targeting the restoration of knee biomechanics similar to healthy controls to prevent early-onset degeneration that is frequently associated with altered biomechanics.

Validity of and recommendations for knee joint acoustic assessments during different movement conditions

Knee joint sounds contain information on joint health, morphology and loading. These acoustic signals may be elicited by further, as yet unknown factors. By assessing potential elicitors and their relative contributions to the acoustic signal, we investigated the validity of vibroarthrographic assessments during different movement conditions with the aim to derive recommendations for their practical usage. Cross-sectional study. Nineteen healthy participants (24.7 ± 2.8 yrs, 7 females) performed five movements: level walking, descending stairs, standing up, sitting down, and forward lunge. Knee joint sounds were recorded by two microphones (medial tibial plateau, patella). Knee joint kinematics and ground reaction forces were recorded synchronously to calculate knee joint moments (Nm/Kg). The mean amplitude (dB) and the median power frequency (Hz) were determined. A repeated measures mixed model investigated the impact of potential predictors (sagittal, frontal, transverse plane and total knee joint moments, knee angular velocity, age, sex, body mass index (BMI) and Tegner Activity Score (TAS)). Most of the amplitudes variance is explained by between-subject differences (tibia: 66.6%; patella: 75.8%), and of the median power frequencies variance by the movement condition (tibia: 97.6%; patella: 98.9%). The final model revealed several predictor variables for both sensors (tibia: sagittal plane, frontal plane, and total knee joint moments, age, and TAS; patella: sagittal plane knee moments, knee angular velocity, TAS). The standardization of the execution of the activities, a between-group matching of variables and the inclusion of co-variates are recommended to increase the validity of vibroarthrographic measurements during different movement conditions of the knee joint.

Percentage Contribution of Lower Limb Moments to Vertical Ground Reaction Force in Normal Gait

Objective

The purpose of this study was to investigate how the hip, knee, and ankle moments in the sagittal plane contribute to the vertical ground reaction force (GRF) in healthy participants during normal speed of walking.

Methods

Forty healthy male individuals volunteered to participate in this study. They were filmed using 6 high-speed (120 Hz) Pro-Reflex infrared cameras (Qualisys) while walking on an Advanced Mechanical Technology Incorporation force platform. The data collected were the percentage contribution of the moments of the hip, knee, and ankle joints in the sagittal plane at the instant of occurrence of the first peak, second peak, and trough of the vertical GRF.

Results

The results revealed that at the first peak of the GRF (loading response), the highest contribution was generated from the knee extension moment followed by the hip extension moment. Knee flexion and ankle plantar flexion moments produced a high contribution to the trough of the GRF (midstance) with approximately equal values. The second peak of the GRF was mainly produced by the ankle plantar flexion moment.

Conclusion

The role of hip extension moment is secondary to knee extension moment in the first peak of GRF. Knee flexion moment is secondary to ankle plantar flexion moment in the second peak of GRF. Both knee flexion and ankle plantar flexion moments have equal contribution during midstance.

Effects of a valgus unloader brace in the medial meniscectomized knee joint: a biomechanical study

Background

Patients undergoing total or partial arthroscopic meniscectomy for treating traumatic meniscal tears are at greater risk of developing knee osteoarthritis (OA) due to increased mechanical load. The purpose of this study was to evaluate the effects of a valgus unloader brace in the medial meniscectomized knee joint during the gait cycle.

Methods

A three-dimensional finite element model of the knee joint was developed using the substructures segmented from magnetic resonance images. Experimentally measured forces and moments for one complete gait cycle, without brace and with brace at three different alignment angles (0°, 4°, and 8°), were applied to the finite element model, and the changes in the tibiofemoral contact mechanics were estimated.

Results

The brace in 0°/4°/8° valgus alignment modes reduced the total contact force in the medial compartment by 16%/46%/82% at opposite toe off and 18%/17%/29% at opposite initial contact events, while it increased the total contact force in the lateral compartment by 31%/81%/110% at opposite toe off and 30%/38%/45% at opposite initial contact events, respectively, when compared to the unbraced meniscectomized knee.

Conclusions

Increasing the valgus alignment from 0° to 4° and 8° resulted in a greater reduction of contact conditions (total contact force, total contact area, peak contact pressure) in the medial compartment and vice versa in the lateral compartment. This decrease in contact conditions in the medial compartment infers enhanced knee joint function due to a valgus unloader brace, which translates to increased knee-related confidence. Results suggest choosing a higher valgus alignment angle could potentially increase the risk for the onset of osteoarthritis in the lateral compartment, and this computational model could be used in validating the effectiveness of braces on joint health.

Electronic supplementary material

The online version of this article (10.1186/s13018-019-1085-1) contains supplementary material, which is available to authorized users.

Is ACL deficiency always a contraindication for medial UKA? Kinematic and kinetic analysis of implanted and contralateral knees

BACKGROUND

Prevalence of knee osteoarthritis increases because life expectancy continues to rise with an active patient population. Hence, the concept of unicompartmental knee arthroplasty (UKA) has regained popularity as a treatment option for unicompartmental knee osteoarthritis. Anterior cruciate ligament (ACL) deficiency is widely considered as a contraindication for UKA, however, there are conflicting reports. If otherwise indicated, some surgeons consider UKA for ACL-deficient patients using a modified surgical technique, with a reduction of posterior tibial slope.

RESEARCH QUESTION

The purpose of this study was to evaluate outcomes in UKA patients with ACL deficiency in comparison to a conventional UKA group (intact ACL) by the measurement of knee kinematics and kinetics.

METHODS

Ten patients with conventional UKA and an intact ACL and eight patients with an ACL-deficient UKA and a reduced posterior tibial slope relative to the native knee were recruited. Three-dimensional joint kinematics of the knee were measured, using skin markers and an infrared optical motion capture system. Ground reaction forces (GRF) were measured with force plates in all three directions. Level walking, ramp descent and stair descent were analyzed, comparing implanted and contralateral native knees and the two UKA groups.

RESULTS

No significant differences in kinetics and kinematics were observed between conventional UKA and ACL-deficient UKA groups for any of the activities. However, some asymmetries in GRF between the implanted and contralateral side were present for the ACL-deficient group, during level walking (unloading rate) and stair descent (stance time).

SIGNIFICANCE

Promising outcomes of the ACL-deficient UKA group suggest that ACL deficiency may not always be a contraindication. Therefore, ACL-deficient UKA could be an alternative treatment option to total knee arthroplasty for an appropriate surgeon selected patient population.

Gait oscillation analysis during gait and stair-stepping in elder patients with knee osteoarthritis

Background

Evaluation of knee and lower limb function alone is not sufficient to assess gait. For accurate assessment of gait abnormality, gait oscillation should also be measured. The goal of this analysis was to assess the influence of the knee joint on gait oscillation during gait and stair-stepping in patients with osteoarthritis of the knee.

Methods

In 33 patients diagnosed with knee osteoarthritis and 33 healthy adults as the control group, we examined acceleration (anterior and lateral directions) and gait barycentric factors (single-support phase and ratio of center of gravity maximum values) during gait and stair-stepping.

Results

Acceleration in the anterior direction in the sacral region was greater in healthy adults than in osteoarthritis (OA) patients during gait and stair-down. Acceleration in the anterior direction in the dorsal vertebral region was greater in OA patients than in healthy adults during (up and down) stair-stepping. Acceleration in the lateral direction in the sacral region was greater in healthy adults than in OA patients during stair-up. Acceleration in the lateral direction in the dorsal vertebral region was greater in OA patients than in healthy adults during stair-stepping. The single-support phase was close to 1 for gait and stair-stepping in healthy adults and OA patients. The single-support time was largely the same for gait and stair-stepping in healthy adults. On the other hand, the single-support time was longer for stair-stepping than for gait in OA patients. The ratio of the center of gravity maximum values was greater for the sacral region than for the dorsal vertebral region. There was a significant difference in the stair-stepping ratio of the center of gravity maximum values between healthy adults and OA patients for the sacral region.

Conclusion

We considered that knee OA influenced acceleration in the anterior and lateral direction in the dorsal vertebral and the ratio of the center of gravity maximum values on gait oscillation.

Comparison between kinetic and kinetic-kinematic driven knee joint finite element models

Use of knee joint finite element models for diagnostic purposes is challenging due to their complexity. Therefore, simpler models are needed for studies where a high number of patients need to be analyzed, without compromising the results of the model. In this study, more complex, kinetic (forces and moments) and simpler, kinetic-kinematic (forces and angles) driven finite element models were compared during the stance phase of gait. Patella and tendons were included in the most complex model, while they were absent in the simplest model. The greatest difference between the most complex and simplest models was observed in the internal-external rotation and axial joint reaction force, while all other rotations, translations and joint reaction forces were similar to one another. In terms of cartilage stresses and strains, the simpler models behaved similarly with the more complex models in the lateral joint compartment, while minor differences were observed in the medial compartment at the beginning of the stance phase. We suggest that it is feasible to use kinetic-kinematic driven knee joint models with a simpler geometry in studies with a large cohort size, particularly when analyzing cartilage responses and failures related to potential overloads.

Joint loading and proximal tibia subchondral trabecular bone microarchitecture differ with walking gait patterns in end-stage knee osteoarthritis

OBJECTIVES

To (1) stratify patient subgroups according to their distinct walking gait patterns in end-stage knee osteoarthritis (OA); (2) compare measures of joint loading and proximal tibia subchondral trabecular bone (STB) microarchitecture among these gait subgroups.

DESIGN

Twenty-five knee OA patients undergoing total knee arthroplasty (TKA) had pre-operative gait analysis. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four tibial condylar regions of interest. Peak knee moments were input to k-means cluster analysis, to identify subgroups with homogeneous gait patterns. Joint loading and STB microarchitecture parameters were compared among gait subgroups (Kruskal-Wallis, Bonferroni-corrected Mann-Whitney U tests).

RESULTS

Three gait subgroups were revealed: biphasics (n = 7), flexors (n = 9), counter-rotators (n = 9). Peak knee adduction moment (KAM) and KAM impulse were significantly higher (P < 0.05) in biphasics than in flexors and counter-rotators (KAM = -0.65, -0.40 and -0.21 Nm/kg, respectively), suggesting a higher medial-to-lateral tibiofemoral load ratio in biphasics. Interestingly, STB medial-to-lateral bone volume fraction (BV/TV) ratio was also significantly higher (more than double) in biphasics and flexors than in counter-rotators (2.24, 2.00 and 1.00, respectively), whereas in biphasics it was only 10% higher than in flexors and not significantly so.

CONCLUSIONS

Within the confines of the limited sample size, data suggests that different mechanisms between the biphasic and flexor gait subroups may generate comparable loads upon the tibial plateau and corresponding bony responses, despite significantly lower KAM indices in flexors. Hence, in flexor gait OA patients, conservative treatments designed to reduce KAM, may not be appropriate. Understanding joint loading among walking gait patterns and relationships to bone microarchitecture may aid at identifying/improving management of persons at risk for developing knee OA.

Importance of Patella, Quadriceps Forces, and Depthwise Cartilage Structure on Knee Joint Motion and Cartilage Response During Gait

In finite-element (FE) models of the knee joint, patella is often omitted. We investigated the importance of patella and quadriceps forces on the knee joint motion by creating an FE model of the subject's knee. In addition, depthwise strains and stresses in patellar cartilage with different tissue properties were determined. An FE model was created from subject's magnetic resonance images. Knee rotations, moments, and translational forces during gait were recorded in a motion laboratory and used as an input for the model. Three material models were implemented into the patellar cartilage: (1) homogeneous model, (2) inhomogeneous (arcadelike fibrils), and (3) random fibrils at the superficial zone, mimicking early stages of osteoarthritis (OA). Implementation of patella and quadriceps forces into the model substantially reduced the internal–external femoral rotations (versus without patella). The simulated rotations in the model with the patella matched the measured rotations at its best. In the inhomogeneous model, maximum principal stresses increased substantially in the middle zone of the cartilage. The early OA model showed increased compressive strains in the superficial and middle zones of the cartilage and decreased stresses and fibril strains especially in the middle zone. The results suggest that patella and quadriceps forces should be included in moment- and force-driven FE knee joint models. The results indicate that the middle zone has a major role in resisting shear forces in the patellar cartilage. Also, early degenerative changes in the collagen network substantially affect the cartilage depthwise response in the patella during walking.

Sound limb loading in individuals with unilateral transfemoral amputation across a range of walking velocities

BACKGROUND

Individuals with unilateral transfemoral amputation demonstrate significantly increased rates of osteoarthritis in their sound knee. This increased risk is likely the result of altered knee mechanical loading and gait compensations resulting from limited function in the prosthetic limb. Altered knee loading as calculated using loading rates and peak external knee adduction moments and impulses have been associated with both the development and progression of knee osteoarthritis in other populations. The purpose of this study was to determine if young individuals with transfemoral amputation demonstrate biomechanical indicators of increased knee osteoarthritis risk.

METHODS

Fourteen young male Service Members with unilateral transfemoral amputation and 14 able-bodied service members underwent biomechanical gait analysis at three standardized walking velocities. A two-way ANOVA (group × speed) with unpaired comparisons with Bonferroni-Holm post-hoc corrections assessed statistical significance and effect sizes (d) were calculated.

FINDINGS

Normalized peak external knee adduction moments and impulses were 25.7% (P < 0.014, d > 0.994) and 27.1% (P < 0.012, d > 1.019) lower, respectively, in individuals with trans-femoral amputation than controls when averaged across speeds, and effect sizes were large. External knee flexor moments were not, however, different between groups and effect sizes were generally small (P > 0.380, d < 0.338). Maximal loading rates were significantly greater in individuals with amputation and effect sizes were large (P < 0.001, d > 1.644).

INTERPRETATION

Individuals with transfemoral amputation did not demonstrate biomechanical risk factors for high medial compartment knee joint loads, but the increased loading rates could place the sound knee at greater risk for cartilage or other tissue damage, even if not localized to the medial compartment.

Biomechanical risk factors for knee osteoarthritis when using passive and powered ankle-foot prostheses

BACKGROUND

Gait compensations following transtibial amputation negatively affect sound limb loading and increase the risk of knee osteoarthritis. Push-off assistance provided by new powered prostheses may decrease the demands on the sound limb. However, their effects in a young population in the early stages of prosthetic use are still unknown. The purpose of this study was to compare limb loading between 1. passive and powered ankle-foot prostheses, 2. sound and amputated limbs, and 3. individuals with amputations in the relatively early stages of prosthetic use and controls.

METHODS

Ten young, active individuals with unilateral transtibial amputation and 10 controls underwent biomechanical gait analysis at three speeds. The peak external knee flexor and adductor moments, adductor moment's angular impulse, peak vertical ground reaction force and loading rate were calculated. Repeated measures ANOVAs compared between limbs, prostheses, and groups.

FINDINGS

The powered prosthesis did not decrease the sound limb's peak adduction moment or its impulse, but did decrease the external flexor moment, peak vertical force and loading rate as speed increased. The powered prosthesis decreased the loading rate from controls. The sound limb did not display a significantly greater risk for knee osteoarthritis than the intact limb or than controls in either device.

INTERPRETATION

In the early stages of prosthetic use, young individuals with transtibial amputation display few biomechanical risk factors for knee osteoarthritis development. However, a powered ankle-foot prosthesis still offers some benefits and may be used prophylactically to mitigate potential increases of these variables with continued prosthetic use over time.