Nordic hamstring exercises in functional knee rehabilitation after anterior cruciate ligament reconstruction: a prospective, randomised, controlled study

To study the effect of using Nordic hamstring exercise method on muscle strength and knee joint stability of patients after ACL reconstruction. 60 patients admitted to our hospital for ACL reconstruction were randomly divided into a test group (n = 30, applying Nordic hamstring exercise) and a control group (n = 30, applying conventional rehabilitation training methods), and the difference in the circumference of the thighs of the patients in the two groups was analysed after training, and the peak torque (PT), total torque (PT), and flexion and extension strength were measured by using the Biodex system3 Multi-joint Isokinetic Testing System at knee joints with an angular velocity of 60°/s and 120°/s. The peak torque (PT), total work (TW), and average peak torque (AVG PT) were measured by extension and flexion strength at angular velocity, and the Lysholm Knee Score was used to assess the knee function of 60 patients. There was no difference in the difference in thigh circumference between the two groups before surgery (P > 0.05); the difference in thigh circumference between the patients in the test group at 12 and 24 weeks after surgery was (− 0.35 ± 0.22) cm and (0.12 ± 0.03) cm, respectively, which were higher than those in the control group, (− 0.51 ± 0.15) cm and (− 0.41 ± 0.34) cm (P