RESUMEN
BACKGROUND: Subchondral bone cyst (SBC) formation is often identified in patients with osteoarthritis. Furthermore, several studies have shown that expression of matrix metalloproteinases (MMPs) is elevated in patients with OA. OBJECTIVES: The aim of our study is to correlate the presence of SBCs and MMP-1 expression with the osteochondral alterations during OA progression. METHODS: We studied the cartilage and subchondral bone of 15 patients who had undergone total knee or hip replacement due to primary OA. As controls, we used the femoral heads of three patients without macroscopic OA changes. We evaluated three specimens per patient. RESULTS: Specimens were divided in four groups based on the Mankin histological severity score. Using immunohistochemistry, we noted SBCs at the site of greatest disease severity. Specifically, these were present more frequently in group III (Mankin score: 6-7) and IV (Mankin: ≥ 8), compared with group I (Mankin: 1-3) and II (Mankin: 4-5). Mild OA stages (Mankin: 1-6) were characterized by degeneration and thinning of the cartilage, followed by increased osteoblast and osteoclast activity of the subjacent bone and the subsequent appearance of SBCs. Simultaneously, we observed expression of MMP-1 in groups I and II in the cartilage and III and IV in both the cartilage and the subchondral bone. Moreover, osteoblast-like cells in the lining of the SBCs showed an increased expression of MMP-1 in stages III and IV. CONCLUSION: Our study provides immunohistological evidence that SBCs accumulate in advanced OA and contain activated cells, which express MMP-1, suggesting that they may thus participate in the osteochondral changes of OA. LEVEL OF EVIDENCE: Level III; prospective comparative study.
Asunto(s)
Quistes Óseos/patología , Cartílago Articular/patología , Metaloproteinasa 1 de la Matriz/metabolismo , Osteoartritis/enzimología , Osteoartritis/patología , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biomarcadores/metabolismo , Quistes Óseos/enzimología , Quistes Óseos/fisiopatología , Cartílago Articular/enzimología , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Osteoartritis/fisiopatología , Osteoartritis de la Cadera/enzimología , Osteoartritis de la Cadera/patología , Osteoartritis de la Cadera/fisiopatología , Osteoartritis de la Rodilla/enzimología , Osteoartritis de la Rodilla/patología , Osteoartritis de la Rodilla/fisiopatología , PronósticoRESUMEN
This mixed method paper explored the effect of family structure on children's physical activities and sedentary pursuits. It furthers the limited understanding of how family structure impacts on children's time in, and reasons behind engaging in, certain physical activities. Children from three inner city comprehensive schools in the Midlands, United Kingdom, participated through questionnaires (n = 381) and semi-structured interviews (n = 62). The results indicated that boys and girls from single parent families spent more time in sedentary activities during the week and at the weekend (P < 0.01) when compared with their intact couple family counterparts. It was identified that children in single-parent families received less parental support due to a lack of time, transport and additional parental responsibilities that created a family environment that encouraged sedentary pursuits. Moreover, the barriers that encouraged sedentary activities also prevented children in single parent families from engaging in lifetime activities during the week. Children from intact couple families recorded more time in lifetime activities than those in single parent families (P < 0.01). Finally, children in two-parent families had more opportunities to engage not only in these activities individually but also in joint activities with their parents, further reinforcing these behaviours.