Validity of gait parameters for hip flexor contracture in patients with cerebral palsy

Musculoskeletal modeling and movement simulation for structural hip disorder research: A scoping review of methods, validation, and applications

Musculoskeletal modeling is a powerful tool to quantify biomechanical factors typically not feasible to measure in vivo, such as hip contact forces and deep muscle activations. While technological advancements in musculoskeletal modeling have increased accessibility, selecting the appropriate modeling approach for a specific research question, particularly when investigating pathological populations, has become more challenging. The purposes of this review were to summarize current modeling and simulation methods in structural hip disorder research, as well as evaluate model validation and study reproducibility. MEDLINE and Web of Science were searched to identify literature relating to the use of musculoskeletal models to investigate structural hip disorders (i.e., involving a bony abnormality of the pelvis, femur, or both). Forty-seven articles were included for analysis, which either compared multiple modeling methods or applied a single modeling workflow to answer a research question. Findings from studies comparing methods were summarized, such as the effect of generic versus patient-specific modeling techniques on model-estimated hip contact forces or muscle forces. The review also discussed limitations in validation practices, as only 11 of the included studies conducted a validation and used qualitative approaches only. Given the lack of information related to model validation, additional details regarding the development and validation of generic models were retrieved from references and modeling software documentation. To address the wide variability and under-reporting of data collection, data processing, and modeling methods highlighted in this review, we developed a template that researchers can complete and include as a table within the methodology section of their manuscripts. The use of this table will help increase transparency and reporting of essential details related to reproducibility and methods without being limited by word count restrictions. Overall, this review provides a comprehensive synthesis of modeling approaches that can help researchers make modeling decisions and evaluate existing literature.

Three decades of gait index development: A comparative review of clinical and research gait indices

BACKGROUND

A wide variety of indices have been developed to quantify gait performance markers and associate them with their respective pathologies. Indices scores have enabled better decisions regarding patient treatments and allowed for optimized monitoring of the evolution of their condition. The extensive range of human gait indices presented over the last 30 years is evaluated and summarized in this narrative literature review exploring their application in clinical and research environments.

METHODS

The analysis will explore historical and modern gait indices, focusing on the clinical efficacy with respect to their proposed pathology, age range, and associated parameter limits. Features, methods, and clinically acceptable errors are discussed while simultaneously assessing indices advantages and disadvantages. This review analyses all indices published between 1994 and February 2021 identified using the Medline, PubMed, ScienceDirect, CINAHL, EMBASE, and Google Scholar databases.

FINDINGS

A total of 30 indices were identified as noteworthy for clinical and research purposes and another 137 works were included for discussion. The indices were divided in three major groups: observational (13), instrumented (16) and hybrid (1). The instrumented indices were further sub-divided in six groups, namely kinematic- (4), spatiotemporal- (5), kinetic- (2), kinematic- and kinetic- (2), electromyographic- (1) and Inertial Measurement Unit-based indices (2).

INTERPRETATION

This work is one of the first reviews to summarize observational and instrumented gait indices, exploring their applicability in research and clinical contexts. The aim of this review is to assist members of these communities with the selection of the proper index for the group in analysis.

A rat model of hip joint contracture induced by mono-articular hip joint immobilization

BACKGROUND

To elucidate the formation process and therapeutic targets of hip flexion contracture, we developed a rat model of hip flexion contracture induced by hip mono-articular immobilization.

METHODS

Kirschner wires inserted into the femur and hip bone were anchored at the hip in a flexed position in the immobilization groups and unanchored in the sham groups for up to four weeks. Age-matched untreated rats were used as controls. Hip extension range of motion (RoM) was measured at three different extension moments (7.5, 15, and 22.5 N•mm) in each successive myotomy step as follows: before myotomy, after sequential myotomy of the tensor fascia lata, quadriceps muscle, iliopsoas muscle, and after myotomy of all residual muscles (the gluteus medius and adductor muscles). Histological analysis of the hip joint was also performed.

FINDINGS

After four weeks of immobilization, the RoM before myotomy at 22.5 N•mm was significantly decreased by 29° compared with controls, and this value was unaltered in the sham group. Analyses following serial myotomy suggested that the structures responsible for myogenic contracture were the tensor fascia lata, iliopsoas, gluteus medius, and adductor muscles because the RoMs were increased by these myotomies. Unexpectedly, arthrogenic contracture was not detected at moments other than at 7.5 N•mm, even after four weeks of immobilization. Histological analysis confirmed that pathological changes were not apparent in the anterior capsule of the hip joint.

INTERPRETATION

The present findings suggest that myogenic contracture may be an important therapeutic target for immobilization-induced hip flexion contracture.

Gait deficits and dynamic stability in children and adolescents with cerebral palsy: A systematic review and meta-analysis

BACKGROUND

Studies have demonstrated that ambulatory children and adolescents with cerebral palsy demonstrate atypical gait patterns. Out of numerous gait variables, identification of the most deteriorated gait parameters is important for targeted and effective gait rehabilitation. Therefore, this study aimed to identify the gait parameters with the most discriminating nature to distinguish cerebral palsy gait from normal gait.

METHODS

Multiple databases were searched to include studies on ambulatory children and adolescents with cerebral palsy that included gait (spatio-temporal, kinematic, and kinetic) and dynamic stability variables.

FINDINGS

Of 68 studies that met the inclusion criteria, 35 studies were included in the meta analysis. Effect size was used to assess the discriminative strength of each variable. A large effect (≥ 0.8) of cerebral palsy on double limb support time (Standardized Mean Difference = 0.98), step length (Standardized Mean Difference = 1.65), step width (Standardized Mean Difference = 1.21), stride length (Standardized Mean Difference = 1.75), and velocity (Standardized Mean Difference = 1.42) was observed at preferred-walking speed. At fast-walking speed, some gait variables (i.e. velocity and stride length) exhibited larger effect size compared to preferred-walking speed. For some kinematic variables (e.g. range of motion of pelvis), the effect size varied across the body planes.

INTERPRETATION

Our systematic review detects the most discriminative features of cerebral palsy gait. Non-uniform effects on joint kinematics across the anatomical planes support the importance of 3D gait analysis. Differential effects at fast versus preferred speeds emphasize the importance of measuring gait at a range of speeds.

Three-Dimensional Kinematic Motion Analysis of Shivers in Horses: A Pilot Study

Our aim was to assess three-dimensional kinematic motion analysis as an objective diagnostic tool for the characterization of the movement disorder of Shivers in horses. Kinematic parameters were measured in three horses with Shivers and were compared with a control group of four normal horses. Multiple parameter differences were found in the horses with Shivers at the walk, during backing, and when asked to pick up their hindlimbs. Most significant changes were a wider hindlimb stance of 0.39 ± 0.15 m and increased abduction angle of 48.7 ± 7.52° and hoof elevation (0.77 ± 0.08 m left and 0.94 ± 0.11 m right) when the horses were asked to pick up their hindlimbs. Control horses could back easily in a straight line and with symmetrical hoof separation and could maintain their center of weight when picking up their hindlimbs. In contrast, the horses with Shivers had difficulty backing straight, were slower, with a shorter stride and asymmetric hoof separation. They could not maintain their center of balance when picking up their hindlimbs. The findings of this pilot study advance the understanding of the movement disorder of Shivers and could be used as outcome measures to evaluate treatment modalities.

Intramuscular psoas lengthening during single-event multi-level surgery fails to improve hip dynamics in children with spastic diplegia. Clinical and kinematic outcomes in the short- and medium-terms

BACKGROUND

In children with spastic diplegia, hip extension in terminal stance is limited by retraction of the psoas muscle, which decreases stride propulsion and step length on the contralateral side. Whether intramuscular psoas lengthening (IMPL) is effective remains controversial. The objective of this study was to assess the impact of IMPL as a component of single-event multi-level surgery (SEMLS) on spatial and temporal gait parameters, clinical hip flexion deformity, and hip flexion kinematics.

HYPOTHESIS

IMPL as part of SEMLS does not significantly improve hip flexion kinematics.

MATERIALS AND METHODS

A retrospective review was conducted of the medical charts of consecutive ambulatory children with cerebral palsy who had clinical hip flexion deformity (>10°) with more than 10° of excess hip flexion in terminal stance and who underwent SEMLS. The groups with and without IMPL were compared. Preoperative values of the clinical hip flexion contracture, hip flexion kinematics in terminal stance, and spatial and temporal gait parameters were compared to the values recorded after a mean postoperative follow-up of 2.4±2.0 years (range, 1.0-8.7 years). Follow-up was longer than 3 years in 6 patients.

RESULTS

Of 47 lower limbs (in 34 patients) included in the analysis, 15 were managed with IMPL. There were no significant between-group differences at baseline. Surgery was followed in all limbs by significant decreases in kinematic hip flexion and in the Gillette Gait Index. In the IMPL group, significant improvements occurred in clinical hip flexion deformity, walking speed, and step length. The improvement in kinematic hip extension was not significantly different between the two groups. Crouch gait recurred in 3 (8%) patients.

DISCUSSION

The improvement in kinematic hip extension in terminal stance was not significantly influenced by IMPL but was, instead, chiefly dependent on improved knee extension and on the position of the ground reaction vector after SEMLS. IMPL remains indicated only when the clinical hip flexion deformity exceeds 20°.

LEVEL OF EVIDENCE

IV, retrospective study.

Effects of contracture on gait kinematics: A systematic review

BACKGROUND

Contractures of a major joint in the lower limbs may impair human walking in addition to other daily living activities. A contracture is defined as the inability of a joint to perform the full range of motion and excessive resistance during passive mobilization of the joint. Few studies have reported methods describing how to evaluate contractures. Understanding the association among all of these studies seems essential to improve patient management. Therefore, we conducted a systematic review on this topic to elucidate the influence of contractures on gait kinematics.

METHODS

An electronic search in the literature will be conducted. Studies were screened by title and abstract and full texts were evaluated secondarily for definitive inclusion. The quality of the included studies was assessed independently by the two review authors with the Modified Quality Assessment Checklist. The included studies were separated into three categories: pathological contracture versus healthy controls (descriptive), simulated contracture versus healthy controls (experimental), and pre- and post-kinematics after surgical muscle lengthening (surgery).

FINDINGS

From a total of 4402 references, 112 original articles were selected, and 28 studies were identified in this systematic review. No significant difference between raters was observed on the total score of the Modified Quality Assessment Checklist.

INTERPRETATION

Contractures influence walking depending on the location (muscle) and the contracture level (muscle-tendon length). After giving a definition of contracture, this review identified some contracture alterations, such as plantarflexion, knee flexion and hip flexion contractures, with a kinematic description and presented possible different compensations.

Normative Data for an Instrumental Assessment of the Upper-Limb Functionality

Upper-limb movement analysis is important to monitor objectively rehabilitation interventions, contributing to improving the overall treatments outcomes. Simple, fast, easy-to-use, and applicable methods are required to allow routinely functional evaluation of patients with different pathologies and clinical conditions. This paper describes the Reaching and Hand-to-Mouth Evaluation Method, a fast procedure to assess the upper-limb motor control and functional ability, providing a set of normative data from 42 healthy subjects of different ages, evaluated for both the dominant and the nondominant limb motor performance. Sixteen of them were reevaluated after two weeks to perform test-retest reliability analysis. Data were clustered into three subgroups of different ages to test the method sensitivity to motor control differences. Experimental data show notable test-retest reliability in all tasks. Data from older and younger subjects show significant differences in the measures related to the ability for coordination thus showing the high sensitivity of the method to motor control differences. The presented method, provided with control data from healthy subjects, appears to be a suitable and reliable tool for the upper-limb functional assessment in the clinical environment.

Changes of gait parameters and lower limb dynamics in recreational runners with achilles tendinopathy

This study aimed to clarify the mechanical gait changes caused by achilles tendinopathy by comparing gait parameters and changes in hip, knee, and ankle moments between an experimental group (EG) and a control group (CG). Twenty runners with achilles tendinopathy were included in the EG (male/female: 10/10, age: 27.00 ± 4.63), and 20 CG (male/female: 10/10, age: 27.25 ± 4.33) participants were recruited. Subjects walked a 13-m distance at their normal walking speed 5 times to obtain motion analysis and joint moment data. Gait parameter analysis showed significant differences in double-limb support (EG: 22.65 ± 4.26%, CG: 20.37 ± 4.46%), step length (EG: 0.58 ± 0.0 7m, CG: 0.64 ± 0.08 m), step width (EG: 0.16 ± 0.04 m, CG: 0.14 ± 0.05 m), stride time (EG: 1.09 ± 0.10 second, CG: 1.05 ± 0.08 second), and walking speed (EG: 1.09±0.18 m·s(-1), CG: 1.23 ± 0.17 m·s(-1)) between the 2 groups (p < 0.05). Significant differences were found in hip joint moment for initial contact, mid-stance, terminal stance, and pre-swing phases; knee joint moment for initial contact and pre-swing phases; and ankle joint moment for pre-swing and terminal swing phases (p < 0.05). Gait parameters and hip, knee, and ankle moments were altered in runners with achilles tendinopathy. Thus, clinical features of gait changes should be understood for optimal treatment of achilles tendinopathy; further research is required in this field. Key pointsA reduction in gait parameters, namely, step length, stride length, and walking speed, and an increase in double-limb support occurs in runners with achilles tendinopathy.A reduction in the hip extension moment occurs during the initial contact, as well as a reduction in the knee flexion moment from the mid-stance to pre-swing phases, a continuous decrease in the knee flexion moment from the early stance phase, and a reduction in the extension moment during the terminal stance phase.A reduction in the ankle plantar flexion moment occurs from the mid-stance phase and that a reduction in the dorsiflexion moment occurs during the terminal swing phase.

Subtalar arthrodesis alignment: the effect on ankle biomechanics

BACKGROUND

The position, axis, and control of each lower extremity joint intimately affect adjacent joint function as well as whole-limb performance. A review of the literature finds little describing the biomechanics of subtalar arthrodesis and the effect on ankle biomechanics. The purpose of the current study was to establish this effect on sagittal plane ankle biomechanics.

METHODS

A study was performed using a 3-dimensional, validated, computational model of the lower extremity. A subtalar arthrodesis was simulated from 20 degrees of varus to 20 degrees of valgus. At each arthrodesis position, the ankle dorsiflexor and plantarflexor muscles' fiber force, moment arm, and moments were calculated throughout a physiologic range of motion.

RESULTS

Throughout ankle range of motion, plantarflexion and dorsiflexion strength varied with subtalar arthrodesis position. When the ankle joint was in neutral sagittal alignment, plantarflexion strength was maximized in 10 degrees of subtalar valgus, and strength varied by a maximum of 2.6% from the peak 221 Nm. In a similar manner, with the ankle joint in neutral position, dorsiflexion strength was maximized with a subtalar joint arthrodesis in 5 degrees of valgus, and strength varied by a maximum of 7.5% from the peak 46.8 Nm. The change in strength was due to affected muscle fiber force generating capacities and muscle moment arms.

CONCLUSION

The significance of this study is that subtalar arthrodesis in a position of 5 to 10 degrees of subtalar valgus has a biomechanical advantage.

CLINICAL RELEVANCE

This supports previous clinical outcome studies and offers a biomechanical rationale for their generally favorable outcomes.

Hip flexion contracture and diminished functional outcomes in cerebral palsy

BACKGROUND

Hip flexion contracture (HFC) in the ambulatory child with cerebral palsy (CP) may impair function and lead to deteriorations in health-related quality of life. Furthermore, increasing HFC may lead to increasing disability. However, the association between passive range of motion and the measures of function and well-being is unclear. This study was designed to determine whether increasing HFC is associated with functional outcome.

METHODS

A total of 181 children, with an average age of 14.0 ± 10.2 years, were evaluated as part of a multicenter prospective data collection of patients with ambulatory CP. Measurements of HFC were recorded, and patients were evaluated using walking score from Gillette Functional Assessment Questionnaire (FAQ), Gross Motor Function Measure (GMFM), and the Pediatric Outcome Data Collection Instrument (PODCI). Patients were grouped on the basis of severity of HFC: group A, 0 to 14 degrees; group B, 15 to 29 degrees; and group C ≥ 30 degrees. Associations were examined using the Spearman correlation.

RESULTS

There was an inverse association between degree of HFC and FAQ walking score (P<0.01, ρ=-0.25). Similarly, there was an inverse association between the degree of HFC and GMFM parts D (P<0.001, ρ=-0.31) and E (P<0.001, ρ=-0.32). Lastly, the PODCI domains of global function, mobility, and physical function also showed an inverse association with degree of HFC (P<0.001, ρ=-0.24).

CONCLUSIONS

As surgeons treating children with CP, we often rely on joint measurements as an indirect measure of function. This study of children with ambulatory CP suggests that increased HFC from the physician's perspective is associated with deterioration in function from a patient and a therapist's perspective.

LEVEL OF EVIDENCE

Level II, prospective study.