Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.
Anatomy and Cell Biology, Cancer and Translational Medicine Research Unit, Faculty of Medicine, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland.
Sci Rep. 2022 Jul 20;12(1):12415. doi: 10.1038/s41598-022-16231-1.
Gestation increases the biomechanical loading of lower extremities. Gestational loading may influence anthropometrics of articular surfaces in similar means as bone diaphyseal properties. This study aimed to investigate whether gravidity (i.e. number of pregnancies) and parity (i.e. number of deliveries) is associated with knee breadth among middle-aged women. The study sample comprised 815 women from the Northern Finland Birth Cohort 1966. The median parity count of our sample was 2 and the median gravidity count 3. At the age of 46, questionnaires were used to enquire gravidity and parity, and posteroanterior knee radiographs were used to obtain two knee breadth parameters (tibial plateau mediolateral breadth (TPML) and femoral condylar mediolateral breadth (FCML)) as representatives of articular size. The associations of gravidity and parity with knee breadth were analyzed using general linear models with adjustments for height, weight, leisure-time physical activity, smoking, and education years. Individuals with osteoarthritic changes were excluded from our sample. The mean TPML in our sample was 70.3 mm and the mean FCML 71.6 mm respectively. In the fully adjusted models, gravidity and parity showed positive associations with knee breadth. Each pregnancy was associated with 0.11-0.14% larger knee breath (p < 0.05), and each delivery accounted for an increase of 0.20% in knee breadth (p < 0.01). Between-group comparisons showed that multiparous women had 0.68-1.01% larger knee breath than nulli- and primiparous women (p < 0.05). Pregnancies and deliveries seem to increase the mediolateral breadth of the knee. This increase is potentially associated with increased biomechanical loadings during gestation.
妊娠会增加下肢的生物力学负荷。妊娠负荷可能以类似于骨干骺端特性的方式影响关节面的人体测量学。本研究旨在探讨生育次数（即妊娠次数）和产次（即分娩次数）是否与中年女性的膝关节宽度有关。研究样本包括来自芬兰北部出生队列 1966 年的 815 名女性。我们样本的中位产次计数为 2，中位生育次数计数为 3。在 46 岁时，使用问卷询问生育次数和产次，使用后前位膝关节 X 线片获得两个膝关节宽度参数（胫骨平台内外宽度（TPML）和股骨髁内外宽度（FCML））作为关节大小的代表。使用一般线性模型分析生育次数和产次与膝关节宽度的关系，并进行身高、体重、休闲时间体力活动、吸烟和受教育年限的调整。患有骨关节炎改变的个体被排除在我们的样本之外。我们样本的平均 TPML 为 70.3 毫米，平均 FCML 为 71.6 毫米。在完全调整的模型中，生育次数和产次与膝关节宽度呈正相关。每次妊娠与膝关节宽度增加 0.11-0.14%（p<0.05），每次分娩使膝关节宽度增加 0.20%（p<0.01）。组间比较显示，多产妇的膝关节宽度比未产妇和初产妇大 0.68-1.01%（p<0.05）。妊娠和分娩似乎增加了膝关节的内外宽度。这种增加可能与妊娠期间生物力学负荷的增加有关。
