Intra-limb joint coordination measures of upper limb and hand movements: A systematic review.

BACKGROUND: People with central nervous system disorders typically have difficulties in coordination of the upper limb and hand movements, which significantly impairs their activities of daily living. Laboratory-based measures can provide quantitative and objective information about intra-limb coordination to aid the rehabilitation process of this population. However, there is currently no comprehensive review of laboratory-based measures. RESEARCH QUESTIONS: The aim of this review was to identify and summarize laboratory-based intra-limb coordination measures for different upper limb and hand movements. METHODS: Searches were performed in the CINAHL, Embase, IEEE Xplore, MEDLINE, PubMed and Web of Science databases to identify studies published between 2013 and 2022. Two authors independently performed paper selection, data extraction and quality assessment. RESULTS: 21 papers were identified, and six types of coordination measures were classified. These included principal component analysis, continuous relative phase analysis, correlation analysis, regression analysis, uncontrolled manifold analysis, and uncorrelated surrogate data analysis, in descending order of occurrence. Regarding psychometric properties, all measures demonstrated good discriminative validity. However, only the principal component analysis approach and the continuous relative phase analysis approach were found to have good convergent validity and responsiveness, respectively. In terms of their practicality, these measures were primarily utilized for quantifying coordination in individuals with neurological disorders, with a greater emphasis on the coordination of upper limb movements rather than hand movements. SIGNIFICANCE: This review summarized and critiqued the characteristics of six types of joint coordination measures. Researchers and clinicians should therefore select appropriate measures based on individual needs. Future research should continue on analysing coordination in individuals with pathological conditions and exploring the application of these measures in quantifying hand movement coordination, to advance current knowledge and inform rehabilitation practices.

Rapid online correction of reach-to-manipulate movements in children with developmental coordination disorder: A pilot kinematic comparison study.

BACKGROUND: Children with developmental coordination disorder show difficulties in making rapid online corrections, and this has been demonstrated in experiments where reaching/pointing movements were employed. However, typical hand movements in real-life contexts involve subsequent movements, such as grasping and manipulating objects after reaching. This study aimed to reinvestigate online correction of reaching movements that were connected with grasping and object manipulation and to explore its impact on the coordination of subsequent hand movements in children with developmental coordination disorder. METHODS: Five children with developmental coordination disorder and five children with typical development were recruited. Their reach-to-manipulate movements in a double-step task were recorded using motion analysis. The manipulative movements included simple and complex forms of pencil rotation. Movement time, movement velocity, and correlation coefficients between finger joints were derived to quantify their motor performances. FINDINGS: Children with developmental coordination disorder showed longer movement time and deceleration phases during online correction of reaching movement than children without developmental coordination disorder. In subsequent grasping and manipulation movements after online correction, they also exhibited lower correlation coefficients in four to five finger joint couplings that are essential for movement completion, compared to children without developmental coordination disorder. INTERPRETATION: Our findings from the current pilot study suggest that children with developmental coordination disorder have impairments in online correction when reaching for objects and may also have reduced coordination of some finger movements that are important for subsequent grasping and object manipulation. Future studies with larger sample sizes are warranted to confirm these findings.

Lower-limbs' muscle coordination mechanism of healthy preschoolers while walking across obstacles.

RESEARCH BACKGROUND: The obstacle-crossing task is a complex gait task, it requires an advance predict of the obstacle for posture adjustment and accurate control of bilateral legs to ensure crossing the obstacles successfully. By monitoring the activated intensity and duration of muscles in this process, preschoolers' motor ability could be assessed objectively and quantitatively, as well as disclose their potential pathogenesis quality eventually. SCIENTIFIC QUESTION: what are the patterns and characteristics of lower limb muscles when they are facing the obstacle-crossing walking (OW) tasks, and how they coordinate their individual muscle or muscle groups of lower-limbs muscles while walking across obstacles? Thereby, the purpose of this study was first to portray the patterns and characteristics of lower limb muscles of healthy preschoolers while OW motion and second to assess the muscles' coordination mechanism. METHOD: 35 healthy preschoolers and 35 healthy adults' lower limbs' surface electromyography (sEMG) were collected while left and right OW and four muscle groups (Tibialis Anterior, Lateral Gastrocnemius, Rectus Femoris, and Biceps Femoris) were recorded. sEMG variables such as Muscle Activation Time, Total Duration of Activity Time, Average Muscle Activation Rate, and Average Rate of Change were calculated. The paired sample-t-test was used to explore the differences of sEMG variables between preschoolers and adults when obstacle-crossing. RESULTS: Preschoolers would adjust the gait by changing the activation time and activation rate to fulfill the obstacle crossing tasks, but they also showed variations by contrasting to adults. Further, synergy between muscles in leg and thigh were also found. CONCLUSION: Although preschoolers performed well enough to finish the OW tasks, ability gaps were still apparent when compared to adults. Hence, with the help of a deeply recognizable muscle coordination mechanism in OW, motor dysfunction in the lower limbs of preschool children can be effectively identified.

Coordination strategies of lower limb muscles during curve-turning tasks in preschool children.

BACKGROUND: Preschoolers are within their critical time in motion development; while muscles are the fundamental units in motion control and by monitoring activated intensity and duration of muscles, preschooler's motor ability which would disclose their potential pathogenesis quality can be objectively and quantitatively assessed. Although a large number of studies were available on this issue, questions still being there: what are the patterns and characteristics of lower limb muscles when they are facing with the curve walking(CW) tasks; and then how individual muscle or muscle groups coordinated while turning curves. Our purpose of this study is first to portray the patterns and characteristics of lower limb muscles of healthy preschoolers while CW and then to insight their muscles' coordination mechanism and "neuro-musculo-skeletal" feedback during motion. METHOD: 35 healthy preschoolers and 35 healthy adults' lower limbs surface electromyography (sEMG) were collected while left and right CW and four muscle groups (Tibialis Anterior, Lateral Gastrocnemius, Rectus Femoris, and Biceps Femoris) were recorded. sEMG variables such as Muscle Activation Time, Total Duration of Activity Time, Average Muscle Activation Rate and Average Rate of Change were calculated. Paired sample t-test was used to explore the differences of sEMG variables between preschoolers and adults when turning curves. RESULTS: Preschoolers would adjust the gait by changing the activation time and activation rate to fulfill the curve turning tasks; but they also showed variations in coordination mechanism when contrasting with the adults group. Those findings in preschoolers would support to build muscles' coordination mechanism and further insight to neuro-muscular skeletal feedback regulation. CONCLUSION: Although preschoolers performed good enough to switching gait from normal walking to CW, but gaps in their abilities were still apparent when compared to adults. Hence, with the help of highly recognizable muscle coordination mechanism in CW, motor dysfunction in lower limbs of preschool children can be effectively identified.

The coordination of upper and lower limbs in curve-turning walking of healthy preschoolers: Viewed in continuous relative phase.

BACKGROUND: Coordination is the ability to assemble and maintain appropriate relations between joints. Investigating limb coordination in curve-turning (CT) walking could provide insightful information about the coordinating strategies and neuro-musculoskeletal system (NMSS) control in human motion. RESEARCH QUESTION: Although preschoolers have already established an adult-like gait, how preschoolers perform their specific gait pattern when walking in CT and what coordination strategies they would choose during the turning process have not yet been systematically considered. Therefore, this study was aimed to investigate preschoolers' coordination mechanism during asymmetric motion, in order to understand the development of their NMSS control in locomotion. METHODS: Kinematics data in the lower and upper limbs of 45 healthy preschoolers walking with the curve-turning task was measured by the Coda Motion System. The Continuous Relative Phase (CRP) angle and the variability between the knee and ankle, hip and knee, as well as the thorax-humerus joint (THJ) and elbow were calculated. RESULTS: The outcome demonstrates that as the curve angles increased, the stride length and Froude number of preschoolers significantly decreased (p < 0.05 for all); meanwhile, a more out of phase coordination pattern in CRP and an increase in VCRP values were found. Group analysis showed that the significant differences in CRP and VCRP between preschoolers and adults increased with curve angles in all coupled joints - the highest in that of the Knee-Ankle coupling, followed by those of the Hip-Knee and THJ-Elbow. SIGNIFICANCE: Our results suggest that to achieve curve-turning, preschoolers first chose to modify their STP, then to adjust coordination for coupling-joints in the Knee-Ankle, Hip-Knee, and THJ-Elbow systems. Additionally, preschoolers are still in a gait fine-tuning period and their NMSS control of motion is not as precise as that of adults.