关节炎患者软骨下囊性变与全膝置换风险的相关性研究

Research of the relationship between subchondral bone cysts and risk of total knee replacement

目的研究软骨下骨囊性变、骨髓损伤的自然病程,并分析其和膝关节软骨丢失及关节置换风险的相关性。方法 264例骨关节炎患者磁共振随访2年。测量胫骨软骨容量、软骨下骨囊性变、骨髓损伤。记录随访4年中患肢是否行膝关节置换术。结果 48.1%的患者在就诊时即有骨囊性变,这些患者中97.1%同时也伴有骨髓损伤。在2年随访中,31.4%的患者囊性变进展,23.8%囊性变缩小,13例(12.4%)患者囊性变完全消失,13例患者(12.4%)出现新的囊性变。初诊时呈骨囊性改变患者的软骨容量较单纯骨髓损伤的患者少,骨囊性变患者每年软骨丢失率也较单纯骨髓损伤患者高。骨囊性变患者膝关节病变严重程度高,行膝关节置换机会也相应较高。结论骨囊性变存在患者的软骨丢失程度和膝关节置换率高于单纯骨髓损伤患者,提示针对骨囊性变的治疗可能可以延缓关节疾病的进展。观察患者的自然病程,囊性变可以减小,因此其可能成为治疗骨关节炎的靶点。

Objective To examine the natural history of subchondral bone cysts and to determine whether knee cartilage loss and risk of joint replacement are relevant to cysts and bone marrow lesions(BMLs).Methods 264 subjects with knee osteoarthritis(OA) were imaged by using magnetic resonance imaging at baseline and 2 years later.Tibial cartilage volume,subchondral bone cysts and BMLs were measured by using validated methods.We ascertained knee arthroplasty over a 4-year period.Results Bone cysts were present in 48.1% patients,97.1% of whom also had BMLs.Over a 2-year period,cysts progress was found in 31.4% of subjects,12.4% developed new cysts and 23.8% had cysts regress.Bone cysts at baseline were associated with lower tibial cartilage volume compared with those with BMLs only or those with neither.Annual medial cartilage volume loss was greatest in those with bone cysts.As the severity of bone abnormality in the medial compartment and the risk of knee replacement was most likely to happen in patients who had subchondral bone cysts.Conclusions Cartilage loss and risk of knee replacement are higher in patients who had cysts than if only BMLs are present.The result suggests that cysts should be a marker to identify those most likely to benefit from prevention of disease progression.As cysts can regress,it may also be a therapeutic targets in knee OA.