Toutoungi D E, Lu T W, Leardini A, Catani F, O'Connor J J
Cambridge Consultants Ltd., Science Park, Milton Rd, Cambridge, UK.
Clin Biomech (Bristol). 2000 Mar;15(3):176-87. doi: 10.1016/s0268-0033(99)00063-7.
To determine the cruciate ligament forces occurring during typical rehabilitation exercises.Design. A combination of non-invasive measurements with mathematical modelling of the lower limb.Background. Direct measurement of ligament forces has not yet been successful in vivo in humans. A promising alternative is to calculate the forces mathematically.
Sixteen subjects performed isometric and isokinetic or squat exercises while the external forces and limb kinematics were measured. Internal forces were calculated using a geometrical model of the lower limb and the "dynamically determinate one-sided constraint" analysis procedure.
During isokinetic/isometric extension, peak anterior cruciate ligament forces, occurring at knee angles of 35-40 degrees, may reach 0.55x body-weight. Peak posterior cruciate ligament forces are lower and occur around 90 degrees. During isokinetic/isometric flexion, peak posterior cruciate forces, which occur around 90 degrees, may exceed 4x body-weight; the anterior cruciate is not loaded. During squats, the anterior cruciate is lightly loaded at knee angles up to 50 degrees, after which the posterior cruciate is loaded. Peak posterior cruciate forces occur near the lowest point of the squat and may reach 3.5x body-weight.
For anterior cruciate injuries, squats should be safer than isokinetic or isometric extension for quadriceps strengthening, though isokinetic or isometric flexion may safely be used for hamstrings strengthening. For posterior cruciate injuries, isokinetic extension at knee angles less than 70 degrees should be safe but isokinetic flexion and deep squats should be avoided until healing is well-advanced.
Good rehabilitation is vital for a successful outcome to cruciate ligament injuries. Knowledge of ligament forces can aid the physician in the design of improved rehabilitation protocols.
确定典型康复锻炼过程中交叉韧带所承受的力。
下肢非侵入性测量与数学建模相结合。
在人体活体中直接测量韧带力尚未成功。一种有前景的替代方法是通过数学计算力。
16名受试者进行等长和等速或深蹲锻炼，同时测量外力和肢体运动学数据。使用下肢几何模型和“动态确定单侧约束”分析程序计算内力。
在等速/等长伸展过程中，前交叉韧带力峰值出现在膝关节角度为35 - 40度时，可能达到体重的0.55倍。后交叉韧带力峰值较低，出现在约90度时。在等速/等长屈曲过程中，后交叉韧带力峰值出现在约90度时，可能超过体重的4倍；前交叉韧带不受力。在深蹲过程中，前交叉韧带在膝关节角度达到50度之前受力较轻，之后后交叉韧带受力。后交叉韧带力峰值出现在深蹲最低点附近，可能达到体重的3.5倍。
对于前交叉韧带损伤，在加强股四头肌时，深蹲可能比等速或等长伸展更安全，不过等速或等长屈曲可安全用于加强腘绳肌。对于后交叉韧带损伤，膝关节角度小于70度时的等速伸展应该是安全的，但在损伤愈合良好之前应避免等速屈曲和深蹲。
良好的康复对于交叉韧带损伤的成功治疗至关重要。了解韧带力有助于医生设计更好的康复方案。
