Men with Early Degrees of Knee Osteoarthritis Present Functional and Morphological Impairments of the Quadriceps Femoris Muscle

Autor(es)

Serrao, Paula Regina M. S. ^[1] ; Vasilceac, Fernando A. ^[2] ; Gramani-Say, Karina ^[2] ; Lessi, Giovanna C. ^[1] ; Oliveira, Ana Beatriz ^[1] ; Reiff, Rodrigo B. M. ^[3] ; Mattiello-Sverzut, Ana Claudia ^[4] ; Mattiello, Stela M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Phys Therapy, BR-13560 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Gerontol, BR-13560 Sao Carlos, SP - Brazil

^[3] Univ Fed Sao Carlos, Dept Med, BR-13560 Sao Carlos, SP - Brazil

^[4] Univ Sao Paulo, Dept Biomech Med & Rehabil Locomotor Apparat, BR-14049 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AMERICAN JOURNAL OF PHYSICAL MEDICINE & REHABILITATION; v. 94, n. 1, p. 70-81, JAN 2015.
• Citações Web of Science: 6

Resumo

Objective: Quadriceps muscle weakness is common in knee osteoarthritis (OA). Reasons for weakness may include atrophy, reduction in the muscle fibers number, and changes in the muscle activation. It is uncertain when these muscular changes begin to appear. Therefore, the purpose of this study was to determine whether men with early stages of knee OA already had functional and quadriceps muscle morphologic alterations. Design: Forty men were divided into two groups: control group (healthy subjects) and OA group (subjects with knee OA). A biopsy of the vastus lateralis muscle was performed for morphometric analysis. Isokinetic evaluation of knee extensor torque, concentric and eccentric (90 and 180 degrees/sec), was performed simultaneously with vastus lateralis electromyographic activity evaluation. Results: Significant differences were found in knee extensor torque (P < 0.05) and in normalized root mean square (P < 0.01) during the eccentric contractions (both velocities), with higher values for the control group. No differences were found during concentric contractions. The OA group presented greater values of the minimum diameter of type 1 fibers and greater proportion and relative cross-sectional area of type 2b fibers (P < 0.05). Conclusions: Men with early stages of knee OA do not present alterations of concentric strength but had decreased eccentric strength and morphologic quadriceps muscle changes, indicating neuromuscular adaptations. (AU)

• Processo FAPESP: 07/07200-4 - Aspectos funcionais, morfológicos e imuno-histoquímicos do músculo quadríceps femoral de indivíduos com graus I ou II de Osteoartrite de joelho
• Beneficiário: Paula Regina Mendes da Silva Serrão
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto