Kinematic Analysis of Patients before and after Abdominoplasty

Background: Abdominoplasty has consistently been one of the top cosmetic procedures performed each year with a high patient satisfaction rate. Excision of the excess abdominal skin has been shown to reduce low back pain and improve posture. The effects of the excess skin removal would, theoretically, be demonstrated through changes in gait. This study aimed to measure kinematic differences during gait to obtain objective measures for abdominoplasty. Methods: Subjects were recruited from a large, academic plastic surgery clinic. Patients were included if they were 18 years of age, able to walk without an assistive device or any hindrance by any existing medical condition, and were scheduled for abdominoplasty. Kinematic measurements were taken before and after surgery using a plug-in-gait marker set, cameras, and a treadmill. Pre- and postoperative measurements were compared and a post-hoc power analysis was created. Results: Nine total patients were included in the study. Joint angles before and after surgery demonstrated moderate differences. However, analysis revealed few significant differences for spatiotemporal or kinematic variables. The power analysis demonstrated an inadequate number of patients to detect significance. Conclusions: Despite the literature describing subjective and objective improvements following abdominoplasty, we were unable to validate this. Overall, there were noticeable differences in joint angles pre- and postoperatively, though the study is too underpowered to reach statistical significance. This preliminary data shows that if the study was powered through a larger cohort, then more generalizable conclusions could be drawn.

Biomechanics of ankle giving way:A case report of accidental ankle giving way during the drop landing test

Background:Several case studies observed that the lateral ankle sprain resulted from a sudden increase in ankle inversion accompanied by internal rotation.However,without sufficient ankle kinetics and muscle activity information in the literature,the detailed mechanism of ankle sprain is still unrevealed.The purpose of our case report is to present 2 accidental ankle giving way incidents for participants with chronic ankle instability(CAI)and compare to their normal trials with data of kinematics,kinetics,and electromyography(EMG).Case description:Two young female participants accidentally experienced the ankle giving way when landing on a 25°lateral-tilted force plate.3 D kinematics,kinetics,and muscle activity were recorded for the lower extremity.Qualitative comparisons were made between the giving way trials and normal trials for joint angles,angular velocities,moments,centers of pressure and EMG linear envelopes.Results:One participant’s giving way trial displayed increased ankle inversion and internal rotation angles in the pre-landing phase and at initial contact compared to her normal trials.Another participant’s giving way trial exhibited greater hip abduction angles and delayed activation of the peroneus longus muscle in the pre-landing phase versus her normal trials.Conclusion:A vulnerable ankle position(i.e.,more inverted and internally rotated),and a late activation of peroneus activity in the pre-landing phase could result in the ankle giving way or even sprains.A neutral ankle position and early activation of ankle evertors before landing may be helpful in preventing ankle sprains.

Basic science and clinical use of eccentric contractions:History and uncertainties

The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloquently revealed by A.V.Hill and subsequently by his students.When the sliding filament theory was introduced by A.F.Huxley and H.E.Huxley,it was a relatively simple task to link Hill's mechanical observations to the actions of the cross bridges during these shortening and isometric contractions.In contrast,lengthening or eccentric contractions have remained somewhat enigmatic.Dismissed as necessarily causing muscle damage,eccentric contractions have been much more difficult to fit into the cross-bridge theory.The relatively recent discovery of the giant elastic sarcomeric filament titin has thrust a previously missing element into any discussion of muscle function,in particular during active stretch.Indeed,the unexpected contribution of giant elastic proteins to muscle contractile function is highlighted by recent discoveries that twitchin-actin interactions are responsible for the"catch"property of invertebrate muscle.In this review,we examine several current theories that have been proposed to account for the properties of muscle during eccentric contraction.We ask how well each of these explains existing data and how an elastic filament can be incorporated into the sliding filament model.Finally,we review the increasing body of evidence for the benefits of including eccentric contractions into a program of muscle rehabilitation and strengthening.

Dynamic knee valgus kinematics and their relationship to pain in women with patellofemoral pain compared to women with chronic hip joint pain

Background:Dynamic knee valgus(DKV)is an abnormal movement pattern visually characterized by excessive medial movement of the lower extremity during weight bearing.Differences in hip and knee kinematic components of DKV may explain the emergence of different pain problems in people who exhibit the same observed movement impairment.Using a secondary analysis of exiting data sets,we sought to determine whether hip and knee frontal and transverse plane angles during a functional task differed between women with patellofemoral pain and women with chronic hip joint pain and the relationship between joint-specific kinematics and pain in these 2 pain populations.Methods:In the original studies,3-dimensional hip and knee kinematics during a single-limb squat were obtained in 20 women with patellofemoral pain and 14 women with chronic hip joint pain who demonstrated visually classified DKV.Pain intensity during the squat was assessed in both groups.For the secondary analysis,kinematic data were compared between pain groups using their respective control groups as a reference.Within each pain group,correlation coefficients were used to determine the relationship between kinematics and pain during the squat.Results:Hip adduction and contralateral pelvic drop were greater in those with chronic hip joint pain compared to those with patellofemoral pain(effect sizes ≥0.40).Greater knee external rotation(r= 0.47,p= 0.04)was correlated with greater knee pain in those with patellofemoral pain,while greater hip adduction(r = 0.53,p = 0.05)and greater hip internal rotation(r = 0.55,p = 0.04)were correlated with greater hip pain in those with chronic hip joint pain.Conclusion:Hip frontal plane motion was greater in those with chronic hip joint pain compared to those with patellofemoral pain.In both groups,greater abnormal movement at the respective joint(e.g.,knee external rotation in the patellofemoral pain group and hip adduction and internal rotation in the chronic hip joint pain group)was associated with greater pain at that joint during a single-limb squat.

Cross-cultural adaptation and validation of an ankle instability questionnaire for use in Chinese-speaking population

Background:The Identification of Functional Ankle Instability(IdFAI)is a valid and reliable tool to identify chronic ankle instability;however,it was developed in English,thus limiting its usage only to those who can read and write in English.The objectives of our study were to(1)cross-culturally adapt a Chinese(Mandarin)version of the IdFAI and(2)determine the psychometric properties of the Chinese version IdFAI.Methods:The cross-cultural adaptation procedures used by the investigators and translators followed previously published guidelines and included 6 stages:(1)initial translation,(2)synthesis of the translations,(3)back translation,(4)developing the pre-final version for field testing,(5)testing the pre-final version,and(6)finalizing the Chinese version of IdFAI(IdFAI-C).Five psychometric properties of the IdFAI-C were assessed from results of 2 participant groups:bilingual(n=20)and Chinese(n=625).Results:A high degree of agreement was found between the English version of IdFAI and IdFAI-C(intra-class correlation_(2,1)=0.995).An excellent internal consistency(Cronbach'sα=0.89),test—retest reliability(intra-class correlation_(2,1)=0.970),and construct validity(r(625)=0.67)was also found for the IdFAI-C.In addition,the results of exploratory and confirmatory factor analysis indicated that ankle instability was the only construct measured from the IdFAI.Conclusion:The IdFAI-C is a highly reliable and valid self-report questionnaire that can be used to assess ankle instability.Therefore,we suggest that it can be used to effectively and accurately assess chronic ankle instability in clinical settings for Chinese-speaking individuals.

Use of clinical movement screening tests to predict injury in sport

Clinical movement screening tests are gaining popularity as a means to determine injury risk and to implement training programs to prevent sport injury. While these screens are being used readily in the clinical field, it is only recently that some of these have started to gain attention from a research perspective. This limits applicability and poses questions to the validity, and in some cases the reliability, of the clinical movement tests as they relate to injury prediction, intervention, and prevention. This editorial will review the following clinical movement screening tests: Functional Movement Screen?, Star Excursion Balance Test, Y Balance Test, Drop Jump Screening Test, Landing Error Scoring System, and the Tuck Jump Analysis in regards to test administration, reliability, validity, factors that affect test performance, intervention programs, and usefulness for injury prediction. It is important to review the aforementioned factors for each of these clinical screening tests as this may help clinicians interpret the current body of literature. While each of these screening tests were developed by clinicians based on what appears to be clinical practice, this paper brings to light that this is a need for collaboration between clinicians and researchers to ensure validity of clinically meaningful tests so that they are used appropriately in future clinical practice. Further, this editorial may help to identify where the research is lacking and, thus, drive future research questions in regards to applicability and appropriateness of clinical movement screening tools.

Frailty:Past,present,and future?

The prevalence of frailty across the world in older adults is increasing dramatically and having frailty places a person at increased risk for many adverse health outcomes,including impaired mobility,falls,hospitalizations,and mortality.Globally,the concept of frailty is gaining attention and the scientific field has made great strides in identifying and conceptually defining frailty through consensus conferences,in advancing the overall science of frailty by drawing on basic science discoveries including concepts surrounding the hallmarks of aging,resilience,and intrinsic capacities,and in identifying the many challenges faced by professionals within diverse clinical settings.Currently,it is thought that frailty is preventable,thus the identification of a person's degree of frailty is vital.Identification of frailty is achievable through widely used frailty screening tools,which are valid,reliable,and easy to use.Following the identification of a person's degree of frailty,targeted intervention strategies,such as physical activity programs must be implemented.In this perspective,we provide a historical perspective of the frailty field since the last quarter of the 20th century to present.We identify the proposed underlying patho-physiology of multiple physiological systems,including compromised homeostasis and resilience.Next,we outline the available screening tools for frailty with a physical performance assessment and highlight specific benefits of physical activity.Lastly,we discuss current scientific evidence supporting the physical activity rec-ommendations for the aging population and for older adults with frailty.The goal is to emphasize early detection of frailty and stress the value of physical activity.