The Study Of Effects Open And Closed Kinetic Chain Training On Patients With Chronic Ankle Instability Based On Kinetic Chain Theory

Research Objectives: This study using the kinematic chain theory training will open chain and closed chain of overall lower limb rehabilitation programme and is given priority to with the ankle,comparing the conventional rehabilitation scheme to observe different rehabilitation scheme of CAI in patients with lower limb muscle strength,muscle excitability,posture,stability and the influence of FMS score,verify the validity of the overall training plan and open chain and closed chain training of curative effects.Research methods: a total of 36 college students were selected from Xi ’an Institute of Physical Education.Randomly divided into OTG（Open Kinetic chain training group）,CTG（Closed Kinetic chain training group）,RTG（Regular training group）,and BCG（blank control group）,9 in each group.OTG received sandbag-weight straight leg raising training + balance training,CTG received lunge training + balance training,AND RTG received ankle training + balance training.BCG did not receive any intervention,and the intervention lasted for 6 weeks,3 times a week.Hip,knee and ankle flexion and extension isokinetic muscle strength test,lower extremity surface electromyography test,plantar pressure test,Y-balance test and FMS test were performed before and after intervention.All data were processed by SPSS25.0,paired-sample T test was used for contrast in the group,one-way analysis of variance was used for comparison between groups,p<0.05 was significant difference.Results:（1）Isokinetic muscle force test after intervention（maximum peak torque）:（1）OTG significantly improved the muscle strength of hip flexion（P <0.01）,the muscle strength of knee flexion,knee extension and ankle flexion（P <0.05）,the muscle strength of hip flexion,knee extension and ankle flexion was significantly improved than BCG（P <0.05）,and the muscle strength of hip flexion,knee extension and ankle flexion was significantly improved than RTG（P <0.05）.（2）In CTG closed chain group,the muscle strength of hip flexion,hip extension,knee extension and ankle flexion was significantly improved（P <0.05）,the muscle strength of hip flexion,hip extension and ankle flexion was significantly improved than that of BCG（P <0.05）,and Hip flexion,hip extension,knee extension muscle strength was significantly improved than that of RTG（P <0.05）.（3）The maximum peak torque of hip flexion was significantly improved by OTG than by CTG（P <0.05）.（2）Surface electromyography test（activation time）:（1）The activation time of OTG was significantly advanced in the medial head of biceps femoris,semitendinosus and gastrocnemius muscle（P <0.05）,the activation time of longus peroneus and gastrocnemius lateral head was significantly advanced（P <0.01）,and the advance of longus peroneus,rectus femoris,lateralis femoris and biceps femoris muscle was significantly better than BCGBCG（P <0.05）.The advance of vastus medialis muscle was significantly better than that of RTG（P <0.01）.（2）The activation time of biceps femoris,longus perfibulus and lateral head of gastrocnemius muscle of CTG was significantly advanced（P <0.05）,and the advance of biceps femoris and longus perfibulus muscle was significantly better than that of BCG（P <0.05）.（3）Although the activation time of vastus medialis muscle was delayed after OTG intervention（P >0.05）,it was still activated earlier than CTG（P<0.05）.In general,OTG improved the activation time of muscle more obviously.（3）Y-balance dynamic balance test:（1）OTG significantly increased in front and back middle（P <0.01）,and the degree of improvement was significantly better than BCG（P <0.01）;（2）CTG was significantly increased in front,posteriorly and posteriorly in the middle（P <0.01）,and the degree of increase in front and posteriorly in the middle was conspicuousness higher than that in RTG and BCG（P <0.01）,and the posteriorly in the middle was also significantly higher（P <0.05）.（3）CTG increased significantly in front than OTG（P <0.05）.（4）Plantar pressure test:（1）OTG significantly improved Sway length and ellipse area（P <0.05）,in which Sway length was significantly reduced than BCG（P <0.01）;（2）CTG significantly improved Sway length,elliptic area,Delta X and Delta Y（P <0.05）,and significantly reduced Sway length and Delta Y than BCG（P <0.01）,and significantly reduced elliptic area,Delta X and closed eye Sway length than BCG（P<0.05）.Sway length,elliptic area,Delta X and Delta Y decreased significantly more than RTG（P <0.05）.（3）The decrease degree of CTG in ellipse area and Delta Y was better than that of OTG（P <0.05）.（5）Functional Motion Screening Test（FMS）:（1）THE scores of OTG straight leg raising,left hurdle step and right hurdle step were significantly improved（P <0.01）.The scores of deep squat,left and right split leg squat were significantly improved（P<0.05）.The improvement degree of left and right split leg squat was better than BCG（P <0.01）.The improvement of straight leg raising,left hurdle step,right hurdle step and left squat was better than RTG（P <0.05）.（2）CTG improved significantly in all indexes（P <0.01）,the improvement of left hurdle step,right hurdle step,left split leg squat and right split leg squat was better than BCG and RTG（P <0.01）.（3）CTG was better than OTG in the improvement of the left side score（P <0.05）.Research Conclusions:（1）The open chain program and closed chain program focusing on the overall training of lower limbs are superior to the conventional training focusing on ankle joint training in improving the muscle strength and muscle excitability of CAI patients,especially in improving the stability of dynamic and static posture and reducing the risk of sports injury.（2）In terms of improving muscle strength and muscle excitability,the open-chain scheme was better than the closed-chain scheme;In terms of improving the dynamic and static balance ability and reducing the risk of sports injury,closed chain closed chain is better than open chain.