Age and sex differences in normative gait patterns.

BACKGROUND: A comprehensive understanding of healthy gait patterns is a critical first step towards understanding age-related pathologies and disorders that are commonly associated with mobility limitations throughout aging. Further, consideration of sex-specific gait patterns throughout the lifespan is important, considering biological differences between males and females that can manifest biomechanically, and epidemiological evidence of female sex being a risk factor for some age-related pathologies such as osteoarthritis. RESEARCH QUESTION: The aim of this study was to characterize the differences in lower extremity joint kinematics and kinetics during gait between asymptomatic adult women and men in different age groups (20-40 years, 41-50 years, 51-59 years, 60+ years). METHODS: This was a secondary analysis conducted on instrumented gait data from 154 asymptomatic adult participants (94 females, 60 males). Three-dimensional hip, knee and ankle joint angles and net external moments were calculated and waveform principal component analysis (PCA) was applied to extract major patterns of variability from each. PC scores were examined for significant sex, age and interaction effects using a two-factor ANOVA analysis (p = 0.001). RESULTS: 13 PC features differed between asymptomatic male and female gait patterns, and were independent of age category. No PC features significantly differed between the age groups, and there were no significant sex by age interactions. SIGNIFICANCE: There are significant magnitude and pattern differences in hip, knee and ankle kinematics and kinetics between asymptomatic women and men. As study participants were asymptomatic, these differences do not necessarily correlate with any injury or disease mechanisms. However, these results do suggest the importance of considering sex-specific analyses in gait study design, and the use of sex-specific normative data in clinical gait studies. These results further suggest that consideration of strict age-matching for gait analysis studies using adult controls is not as critical as sex considerations.

Predicting recovery after lumbar spinal stenosis surgery: A protocol for a historical cohort study using data from the Canadian Spine Outcomes Research Network (CSORN).

Background: Symptomatic lumbar spinal stenosis (SLSS) is a condition in which narrowing of the spinal canal results in entrapment and compression of neurovascular structures. Decompressive surgery, with or without spinal fusion, is recommended for those with severe symptoms for whom conservative management has failed. However, significant persistent pain, functional limitations, and narcotic use can affect up to one third of patients postsurgery. Aims: The aim of this study will be to identify predictors of outcomes 1-year post SLSS surgery with a focus on modifiable predictors. Methods: The Canadian Spine Outcomes Research Network (CSORN) is a large database of prospectively collected data on pre- and postsurgical outcomes among surgical patients. We include participants with a primary diagnosis of SLSS undergoing their first spine surgery. Outcomes are measured at 12 months after surgery and include back and leg pain, disability (Oswestry Disability Index, ODI), walking capacity (ODI item 4), health-related quality of life, and an overall recovery composite outcome (clinically important changes in pain, disability, and quality of life). Predictors include demographics (education level, work status, marital status, age, sex, body mass index), physical activity level, smoking status, previous conservative treatments, medication intake, depression, patient expectations, and other comorbidities. A multivariate partial least squares model is used to identify predictors of outcomes. Conclusion: Study results will inform targeted SLSS interventions, either for the selection of best candidates for surgery or the identification of targets for presurgical rehabilitation programs.

Contexte: La sténose spinale lombaire symptomatique (SSL) est une affection dans laquelle le rétrécissement du canal rachidien entraîne le piégeage et la compression des structures neurovasculaires. La chirurgie décompressive, avec ou sans fusion vertébrale, est recommandée pour les personnes présentant des symptômes graves et pour lesquelles la prise en charge conservatrice a échoué. Cependant, une douleur persistante importante, des limitations fonctionnelles et l'usage de narcotiques peuvent affecter jusqu'à un tiers des patients après l'opération.Objectifs: Cette étude aura pour but d'identifier les prédicteurs de résultats un an après l'intervention chirurgicale de la sténose spinale lombaire symptomatique, en mettant l'accent sur les prédicteurs modifiables.Méthodes: Le Canadian Spine Outcomes Research Network (CSORN) est une vaste base de données de patients chirurgicaux collectées de manière prospective comprenant des données sur les résultats pré et postopératoires. Nous inclurons les participants ayant un diagnostic primaire de sténose spinale lombaire symptomatique, qui subissent leur première opération de la colonne vertébrale. Les résultats sont mesurés 12 mois après l'opération et comprennent les douleurs dorsales et aux jambes, le handicap (Oswestry Disability Index, ODI), la capacité de marche (ODI, point 4), la qualité de vie liée à la santé et un résultat composite de récupération globale (changements cliniquement importants dans la douleur, le handicap et la qualité de vie). Les prédicteurs comprendront des données démographiques (niveau d'éducation, situation professionnelle, état civil, âge, sexe, indice de masse corporelle), le niveau d'activité physique, le tabagisme, les traitements conservateurs antérieurs, la prise de médicaments, la dépression, les attentes des patients et d'autres comorbidités. Un modèle multivarié des moindres carrés partiels sera utilisé pour identifier les prédicteurs de résultats.Conclusion: Les résultats de l'étude serviront de base à des interventions ciblées en matière de sténose spinale lombaire symptomatique, soit pour la sélection des meilleurs candidats à la chirurgie, soit pour déterminer des cibles pour les programmes de réadaptation pré-chirurgicale.