Influence of hip stabilization muscles on the dynamic knee valgus and trendelemburg sign in female handball athletes

BACKGROUND: Dynamic knee valgus is a biomechanical dysfunction that predisposes to injuries in athletes. Strengthening exercises and improving neuromotor control of the hip abductor and external rotator muscles might contribute to the pelvis stability and dynamic knee valgus control.METHODS: This prospective-cohort study followed twenty and five female handball players that were submitted to a 36 sessions physiotherapy strengthening and neuromotor control protocol, with functional exercises focused on hip abductor and external rotator muscles. Knee biokinetic was evaluated in the frontal plane by photogrammetry, using the Hudl Technique software 1.3 beta, for measuring the dynamic knee valgus during the Step Down Test and Single Leg Test. Hip muscle instability was also analyzed, by the Trendelenburg test. The variables were compared and was considered significant a P value of 0.05 and confidence interval of 95%. The analyses were carried out through the SPSS software v. 22.RESULTS: Twenty-five athletes enrolled in the study. From them, four were removed because they met exclusion criteria, hence 21 athletes make up the final sample. The training resulted in significant reductions (P<0.05) on the dynamic knee valgus: 5.87° and 7.53°, respectively. It also promoted significative hip muscle stability (P=0.0005), identified by Trendelenburg test.CONCLUSIONS: This study’s results reinforce the importance of the specific exercises for hip abductor and external rotator muscles for correcting dynamic knee valgus and hip stability.