Devita P, Hortobagyi T, Barrier J, Torry M, Glover K L, Speroni D L, Money J, Mahar M T
Department of Exercise and Sport Science, East Carolina University, Greenville, NC 27858, USA.
Med Sci Sports Exerc. 1997 Jul;29(7):853-9. doi: 10.1097/00005768-199707000-00003.
Gait analyses of rehabilitated individuals with anterior cruciate ligament (ACL) deficiency and reconstruction have identified the final adaptations of increased hip extensor torque and hamstring electromyography (EMG) and decreased knee extensor torque and quadriceps EMG during stance. The initial adaptations to injury and surgery are, however, unknown as are the factors that influence the development of the adaptations. Identification of the initial response to injury would provide a basis for determining whether the final adaptations are learned automatically or if they are the result of a lengthy training period in which various factors may affect their development. The purpose of the study was to evaluate the initial effects of ACL injury and reconstruction surgery on joint kinematics, kinetics, and energetics, during walking. Injured limbs from nine subjects with ACL injury were tested 2 wk after injury, and 3 and 5 wk after surgery. Ten healthy subjects were tested. Kinematic and ground reaction data were collected and combined with inverse dynamics to calculate the joint torques and powers. A knee extensor torque throughout most of stance was observed in the injured limbs at all test sessions. This result was in conflict with previous observations of reduced extensor torque or a flexor torque in rehabilitated patients with ACL reconstruction and patients with ACL deficiency. This result also differed from the typical midstance extensor then flexor torque in healthy control subjects. Trend analysis showed a significant (P < 0.001) change in average position at the hip and knee, extensor angular impulse at the hip, and positive work done at the hip 3 wk after surgery followed by a partial rehabilitation at 5 wk after surgery. Power and work produced at the knee were reduced fivefold (P < 0.001) after 5 wk of rehabilitation and did not recover to pre-surgical levels. The existence of a long-lasting knee extensor torque 2 wk after injury indicated that the adaptation process to ACL deficiency is lengthy, requiring many gait cycles, and that numerous factors could be involved in learning the adaptations.
对前交叉韧带（ACL）损伤及重建后的康复个体进行的步态分析表明，在站立期，最终的适应性变化为髋伸肌扭矩和腘绳肌肌电图（EMG）增加，而膝伸肌扭矩和股四头肌EMG降低。然而，损伤和手术后的初始适应性变化以及影响这些适应性变化发展的因素尚不清楚。确定对损伤的初始反应将为判断最终的适应性变化是自动习得的，还是漫长训练期的结果（在此期间各种因素可能影响其发展）提供依据。本研究的目的是评估ACL损伤和重建手术对步行过程中关节运动学、动力学和能量学的初始影响。对9名ACL损伤患者的受伤肢体在受伤后2周、手术后3周和5周进行测试。对10名健康受试者进行测试。收集运动学和地面反力数据，并结合逆动力学计算关节扭矩和功率。在所有测试阶段，受伤肢体在大部分站立期均观察到膝伸肌扭矩。这一结果与先前对ACL重建康复患者和ACL缺损患者伸肌扭矩降低或屈肌扭矩的观察结果相矛盾。这一结果也与健康对照受试者典型的站立中期伸肌然后屈肌扭矩不同。趋势分析显示，手术后3周，髋和膝的平均位置、髋伸肌角冲量以及髋部所做的正功有显著（P < 0.001）变化，随后在手术后5周进行了部分康复。康复5周后，膝关节产生的功率和功降低了五倍（P < 0.001），且未恢复到手术前水平。受伤后2周持续存在的膝伸肌扭矩表明，对ACL缺损的适应过程漫长，需要许多步态周期，并且在学习适应性变化过程中可能涉及众多因素。
