目的:使用动态双平面X线摄影分析在水平行走和下坡跑步过程中慢性ACL缺陷(ACL-D)和未受影响的对侧膝盖的体内运动学和关节运动学。据推测,ACL-D膝盖会表现出增加的前平移和内旋,与未受影响的对侧相比,ACL缺陷会改变胫骨股接触路径。
方法:招募了8名没有不稳定症状的单侧慢性ACL-D患者。对侧未受影响的膝盖被认为是对照。从ACL-D和未受影响的膝盖确定Kellgren-Lawrence(K-L)等级。使用经过验证的基于体积模型的跟踪过程,从脚踏到早期站立阶段(步态周期的20-25%)确定动态膝盖运动,该过程将特定于受试者的CT骨骼模型与动态双平面X射线照片相匹配。参与者以1.2m/s的速度进行水平行走,以2.5m/s的速度进行下坡跑步,同时以每秒100和150张图像收集双翼飞机射线照片,分别。确定并比较ACL-D和未受影响的膝盖之间的胫骨运动和关节运动(关节软骨下骨表面之间最接近的接触点的路径)。使用双向重复测量方差分析来识别在步态周期的5%增量下ACL-D和未受影响的膝盖之间的差异。
结果:在水平行走(所有p<0.001)和下坡跑步(所有p≤0.022)期间,ACL-D的前后平移明显大于未受影响的膝盖。在水平行走和下坡跑步期间,内部旋转显示ACL-D和未受影响的膝盖之间没有显着差异。在下坡跑步期间,ACL-D膝关节股骨上最接近的接触点始终在外侧隔室中更靠前(步态周期的10%至20%显着,所有p≤0.044),但不是在水平行走。未发现内侧隔室接触路径的差异。一半的参与者有不对称的K-L等级,所有受累的膝关节都有更严重的膝关节OA。只有2个相对年轻的个体在任一膝盖中都没有进展到第1阶段。
结论:结果表明,即使没有不稳定症状,ACL-D膝关节的前平移和膝关节接触路径也会改变。临床相关性是,与未受累的肢体相比,未报告不稳定症状的ACL-D患者可能仍表现出膝关节运动学和关节运动学的改变。
方法:病例对照研究,三级。
OBJECTIVE: To analyze the in vivo kinematics and
arthrokinematics of chronic ACL-deficient (ACL-D) and unaffected contralateral knees during level walking and downhill running using dynamic biplane radiography. It was hypothesized that ACL-D knees would demonstrate increased anterior translation and internal rotation, and that ACL-deficiency would alter the tibiofemoral contact paths in comparison to the unaffected contralateral side.
METHODS: Eight participants with unilateral chronic ACL-D without instability symptoms were recruited. The contralateral unaffected knee was considered as control. Kellgren-Lawrence (K-L) grades were determined from ACL-D and unaffected knees. Dynamic knee motion was determined from footstrike through the early-stance phase (20-25% of gait cycle) using a validated volumetric model-based tracking process that matched subject-specific CT bone models to dynamic biplane radiographs. Participants performed level walking at 1.2 m/s and downhill running at 2.5 m/s while biplane radiographs were collected at 100 and 150 images per second, respectively. Tibiofemoral kinematics and
arthrokinematics (the path of the closest contact point between articulating subchondral bone surfaces) were determined and compared between ACL-D and unaffected knees. A two-way repeated measures analysis of variance was used to identify differences between ACL-D and unaffected knees at 5% increments of the gait cycle.
RESULTS: Anterior-posterior translations were significantly larger in ACL-D than unaffected knees during level walking (all p < 0.001) and downhill running (all p ≤ 0.022). Internal rotation showed no significant difference between ACL-D and unaffected knees during level walking and downhill running. Closest contact points on the femur in ACL-D knees were consistently more anterior in the lateral compartment during downhill running (significant from 10 to 20% of the gait cycle, all p ≤ 0.044), but not during level walking. No differences in medial compartment contact paths were identified. Half of the participants had asymmetric K-L grades, with all having worse knee OA in the involved knee. Only 2 relatively young individuals had not progressed beyond stage 1 in either knee.
CONCLUSIONS: The results suggest that anterior translation and knee joint contact paths are altered in ACL-D knees even in the absence of instability symptoms. The clinical relevance is that ACL-D patients who do not report symptoms of instability likely still demonstrate altered knee kinematics and
arthrokinematics compared to their uninvolved limb.
METHODS: Case-control study, Level III.