Effect Of 6-week Blood Flow Restriction Combined With Whole Body Vibration Training On Young Male Patellofemoral Pain Syndrome

Objective: To investigate the therapeutic effect of blood flow restriction combined with whole body vibration training in young male patients with patellofemoral pain syndrome.Methods: 45 eligible young male patients with PFPS were selected and randomly divided into 3 groups with 15 patients in each group: Total body vibration training group（WBVT group,n=15）,blood flow restriction training group（BFRT group,n=15）,blood flow restriction combined with total body vibration training group（combined group,n=15）,the treatment frequency was 3 times a week for 6weeks.The three groups were trained in the bipedal half-squat training posture according to the requirements of the experiment under different intervention conditions.There were 10 groups in each treatment,each group was trained for 60 seconds,and the rest between the groups was 1 minute.In WBVT group,subjects were trained on a working vibration table（vibration frequency: 30 Hz,amplitude:4mm）.Subjects in BFRT group were trained on a non-working vibrating table,and blood flow restriction was performed on the affected limb at 40% arterial occlusion pressure percentage.Subjects in the combined group were trained on a working vibration table（vibration frequency: 30 Hz,amplitude: 4mm）,and blood flow restriction was performed on the affected limb at 40% arterial occlusion pressure percentage on the affected side.The treatment effects of different intervention methods were evaluated by measuring thigh circumference,VAS scale,AKPS scale,relative peak moment,RMS amplitude（%MVC）of vastus medialis muscle,rectus femoris muscle and vastus lateralis muscle,and RMS amplitude ratio of vastus lateralis muscle to vastus medialis muscle.Results:（1）Changes in thigh circumference before and after treatment: intra-group results showed that,compared with before treatment,thigh circumference was significantly increased in the combined group（P < 0.05）,WBVT group and BFRT group（P > 0.05）;The intergroup results showed that compared with before treatment,WBVT group and BFRT group combined group（P > 0.05）;（2）Changes in VAS scores before and after treatment: Intra-group results showed that VAS scores of WBVT group and combined group decreased significantly（P < 0.05）;BFRT group（P > 0.05）;Inter-group results showed that after 6 weeks of treatment,VAS score in the combined group was significantly lower than that in the WBVT group（P < 0.05）and significantly lower than that in the BFRT group（P < 0.01）.（3）Changes in AKPS scores before and after treatment: Intragroup results showed that AKPS scores in WBVT group,BFRT group and combined group were significantly increased compared with before treatment（P < 0.01）;The inter-group results showed that after 6weeks of treatment,AKPS score in the combined group was significantly higher than that in the WBVT group and BFRT group（P < 0.01）.There was no significant difference between WBVT group and BFRT group（P > 0.05）.（4）The change of 60°/Sec relative peak moment value before and after treatment,compared with before treatment,WBVT group and BFRT significantly increased（P < 0.05）,combined group significantly increased（P < 0.01）;The intergroup results showed that after 6weeks of treatment,the combined group was significantly higher than the WBVT group（P < 0.05）and the BFRT group（P < 0.01）;There was no significant difference between WBVT group and BFRT group（P > 0.05）.（5）Changes in RMS（%MVC）of VMO before and after treatment: intra-group results showed that compared with before treatment,the combination group was significantly increased（P < 0.01）,WBVT group and BFRT group（P > 0.05）;The results among groups showed that the combined group was significantly higher than the BFRT group（P < 0.05）,but there was no significant difference among the other groups（P > 0.05）.Changes in RMS（%MVC）of RF before and after treatment: intragroup results showed a significant increase in the combined group compared with before treatment（P < 0.05）.There was no significant difference between WBVT group and BFRT group（P > 0.05）.The results among groups showed that the combined group was significantly higher than the BFRT group（P < 0.05）,but there was no significant difference among the other groups（P > 0.05）.The RMS（%MVC）of VL before and after treatment showed no significant difference among all groups（P > 0.05）.There was no significant difference among all groups（P > 0.05）.Conclusions: Compared with other intervention methods in this study,6-week blood flow restriction combined with whole body vibration training can more effectively increase thigh circumference,relieve knee pain symptoms,improve knee function and knee extension strength,improve VMO and RF muscle recruitment,and balance quadriceps muscle strength in PFPS patients.