Avaliação da arquitetura muscular e aspectos biopsicossociais em indivíduos com osteoartrite de joelho em diferentes faixas etárias

Abstract

The aim of this dissertation was to investigate the influence of muscle architecture parameters and knee extensor strength in individuals with knee osteoarthritis (OA) in different age groups. It was also objective of this dissertation to compare different age groups in order to verify differences in physical function, pain intensity and biopsychosocial factors in individuals with knee OA. Thus, two studies were conducted: Study I: Evaluation of muscle architecture in knee osteoarthritis individuals and its influence on muscle strength in different age groups and Study II: Clinical and functional contributions to the presence of biopsychosocial aspects in patients with knee osteoarthritis in different age groups. Study I: Eighty individuals with and without knee OA: middle-aged osteoarthritis group (KL II / III) aged 40-50 years (n = 20), middle-aged control group aged 40-50 years (n = 20), old-aged osteoarthritis group (KL II / III) with 70 years or more (n = 20) and old-aged control group with 70 years or more (n = 20). All participants were submitted to analysis of isometric and isokinetic knee extensors torques, physical activity level, self-reported measures and muscular architecture of the vastus lateralis muscle by ultrasound. After intergroup statistical analysis, similarity was observed between the middle-aged osteoarthritis group and the old-aged control group for all study variables. The old-aged groups presented muscular architecture parameters and isometric and concentric peak torques smaller in comparison to the middle-age groups, independently of knee OA. In this sense, groups with knee OA also presented significant muscle weakness compared to the control groups in both isometric and concentric strength tests. However, the middle-aged and old-aged osteoarthritis groups showed differences only in the pennation angle and muscle thickness compared to the control groups, matched by age. Regarding the regression analyzes, gender, age, presence of knee OA and pennation angle were independently associated with isometric and concentric peak torques. Study II: Forty knee OA (KL II/III) patients were included in this study: middle-aged osteoarthritis group (40-50 years) (n = 20) and old-aged osteoarthritis group (≥70 years) (n = 20). Participants completed self-reported (WOMAC and visual analog scale) and biopsychosocial measures, as well as performance-based tests. After intergroup analysis, no statistical differences were observed between the age groups, except that the old-aged osteoarthritis spent more time in the stair-climb and 40m fast-paced walk tests compared to the middle-aged osteoarthritis group. The results of the multiple linear regression analyzes showed that the WOMAC total score and the visual analog scale (VAS) were independently associated to Tampa Scale of Kinesiophobia score. However, only the WOMAC total score was associated with the Pain Catastropizing Scale score. Thus, the results of the present dissertation suggest an early muscular aging in individuals with knee OA, characterized by lower pennation angle, fascicle length, muscle thickness, and isometric and concentric strength. In addition, a significant association between biopsychosocial, clinical and functional factors has been demonstrated, regardless of age.