Centre for Interdisciplinary Research in Rehabilitation, Lethbridge-Layton-Mackay Rehabilitation Centre, and School of Physical and Occupational Therapy, McGill University, Montreal, Canada.
Osteoarthritis Research Unit, University of Montreal Hospital Research Centre (CRCHUM), Montreal, Canada.
Clin Biomech (Bristol). 2022 Jun;96:105669. doi: 10.1016/j.clinbiomech.2022.105669. Epub 2022 May 15.
Vastus medialis intramuscular fat has been proposed to be a modifiable determinant of knee cartilage loss in patients with knee osteoarthritis. The objective was to determine whether vastus medialis intramuscular fat relates to osteoarthritis severity and quadriceps muscle strength in patients with non-traumatic and post-traumatic knee osteoarthritis.
For this cross-sectional study, participants with knee osteoarthritis were classified into two groups: non-traumatic (n = 22; mean age = 60 years) and post-traumatic (n = 19; mean age = 56 years). Healthy adults were included (n = 22; mean age = 59 years). A 3-Tesla magnetic resonance imaging was used to measure vastus medialis cross-sectional area and intramuscular fat. Isometric knee extensor muscle torque was assessed using an isokinetic dynamometer and normalized to body mass (Nm/kg). Knee osteoarthritis severity was assessed using standing antero-posterior radiographs (Kellgren-Lawrence scores). Regression analyses examined relationships between 1) vastus medialis intramuscular fat with knee osteoarthritis severity and osteoarthritis group, after accounting for sex and body mass index, and 2) knee extensor muscle torque with vastus medialis intramuscular fat, after accounting for sex and vastus medialis cross-sectional area.
Vastus medialis intramuscular fat was positively associated with body mass index (B = 0.321, P < 0.001), but not with osteoarthritis severity or group (P > 0.05). Higher vastus medialis intramuscular fat was associated with reduced knee extensor muscle torque (B = -0.040, P = 0.018).
Greater vastus medialis intramuscular fat was associated with lower quadriceps muscle strength in patients with knee OA. It is unclear whether this is due to the accumulation of vastus medialis intramuscular fat or other potential factors, such as diet and physical inactivity.
股内侧肌内脂肪被认为是膝关节骨关节炎患者膝关节软骨丢失的可改变决定因素。目的是确定股内侧肌内脂肪与非创伤性和创伤性膝关节骨关节炎患者的骨关节炎严重程度和股四头肌力量是否相关。
这项横断面研究将膝关节骨关节炎患者分为两组：非创伤性（n=22；平均年龄 60 岁）和创伤性（n=19；平均年龄 56 岁）。还纳入了健康成年人（n=22；平均年龄 59 岁）。使用 3T 磁共振成像测量股内侧肌横截面积和肌内脂肪。使用等速测力计评估等长膝关节伸肌肌力，并按体重归一化（Nm/kg）。使用站立前后位 X 线片（Kellgren-Lawrence 评分）评估膝关节骨关节炎严重程度。回归分析检查了 1）股内侧肌内脂肪与膝关节骨关节炎严重程度和骨关节炎组之间的关系，在考虑了性别和体重指数后，2）股四头肌力量与股内侧肌内脂肪之间的关系，在考虑了性别和股内侧肌横截面积后。
股内侧肌内脂肪与体重指数呈正相关（B=0.321，P<0.001），但与骨关节炎严重程度或组无关（P>0.05）。股内侧肌内脂肪越高，膝关节伸肌肌力越低（B=-0.040，P=0.018）。
股内侧肌内脂肪较多与膝关节骨关节炎患者的股四头肌力量较弱相关。尚不清楚这是由于股内侧肌内脂肪的堆积还是其他潜在因素（如饮食和身体活动不足）所致。
