A framework to optimize knee rehabilitation

: investigating the effects of a triplanar rotary based hip-focused therapeutic exercise program on dynamic lower extremity alignment and functional performance

Abstract

Introduction: Dynamic knee valgus (DKV) can be defined as a triplanar medial collapse of the lower extremity and has been identified as a modifiable risk factor shared by both patellofemoral pain (PFP) and anterior cruciate ligament (ACL) injury. Knee valgus is widely addressed in PFP rehabilitation and ACL injury prevention programs with the premise that this modifiable risk factor can be mitigated with exercises in these populations. While proximal hip exercises have shown increases in hip strength, current evidence has reported that increased hip strength fails to alter the kinematic control and position of the pelvis and femur during higher speed athletic tasks such as running and jumping. This thesis involved designing and implementing a complex approach to exercise implementation which may possibly alter kinematic outcomes related to global alignment while performing task specific athletic movements.

Methods: The initial literature review established the theoretical framework forming the basis of the research question. Scoping reviews of both the PFP exercise literature and ACL prevention exercises identified gaps in existing evidence regarding current exercise prescription. A novel rotary based advanced exercise program was then designed incorporating the missing elements noted from the reviews. A 12-wk. feasibility study was performed with a Division I women’s volleyball team (n=13) to trial the new interventions. The main study was a 6-wk. RCT aimed at comparing the current standard of hip strengthening exercise with the newly developed advanced exercises. The main RCT study targeted recreational female runners (n=30) to determine if the advanced exercises would alter global and lower extremity kinematic changes of the trunk, pelvis, and knee valgus angles. Lastly, a 6-wk. single group study was undertaken to explore the association of utilizing the advanced intervention exercises to performance-based outcome measures which measured lower extremity biomechanics, athletic performance, and injury prevention as a secondary outcome.

Results: The RCT found no significant associations between time and group, rejecting the hypothesis that a globally task specific exercise intervention would alter biomechanics in recreational running females. These findings are consistent with current evidence. There were results that favored the treatment group regarding a single leg drop vertical jump in the main study. The final study also identified several associations that favored the treatment group. Both the single leg drop vertical jump and the valgus control exercise favored the treatment group to a greater degree on the athlete’s dominant right lower extremity.

Conclusions: The findings in the RCT support current evidence that exercise alone is incapable of altering biomechanical positions in recreational female runners. The main and single group study demonstrated favorable results during the single leg jump landings, and the single group study did produce favorable results controlling knee valgus in Division 1 female athletes. The work in this thesis represents a step forward toward implementing more globally targeted complex intervention strategies which include more holistic and task specific rotational exercises, directed at the elements identified in common risk factors for knee injury. Future research that includes the intervention strategies developed during this thesis can be applied to future studies in an effort to possibly optimize athletic performance.

Date of Award	Feb 2023
Original language	English
Sponsors	High Point University
Supervisor	Chris Bleakley (Supervisor) & Carla Mc Cabe (Supervisor)