Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation


Health Sciences


Rehabilitation Sciences

First Advisor

Dr. Tony English

Second Advisor

Dr. Carl Mattacola


Background: Lower extremity (LE) musculoskeletal injuries in soccer players are extremely common. These injuries can result in many days of lost time in competition, severely impacting players and their respective teams. Implementation of group injury prevention programs has gained popularity due to time and cost-effectiveness. Though participation in group injury prevention programs has been successful at reducing injuries, programs often target a single injury and all players do not benefit from participation. Players with a greater number of risk factors are most likely to sustain an injury, and unfortunately, less likely to benefit from a group injury prevention program. The purpose of the proposed research is to determine if targeting these high risk players with one-on-one treatment will result in a reduction in the number of risk factors they possess.

Objectives: 1) Determine the effectiveness of one-on-one intervention for reducing the number of risk factors for LE musculoskeletal injury in soccer players with 3 or more risk factors; 2) Assess the effectiveness of matched interventions on reducing the magnitude of identified risk factors.

Hypothesis: Fifty percent or more of subjects receiving one-on-one intervention will have a reduction of ≥ 1 risk factor(s).

Design: Quasi-experimental pretest-posttest design.

Subjects: NCAA Division I men’s and women’s soccer players.

Methods: All subjects were screened for modifiable risk factors using a battery of tests which assessed mobility, asymmetry in fundamental movement pattern performance, neuromuscular control, and pain with movement. Players with ≥ 3 risk factors (“high risk”) were placed in the treatment group and received one-on-one treatment from a physical therapist. An algorithm was created with interventions matched to specific deficits to determine the treatment each subject received. Subjects in the intervention group were treated twice per week for four weeks. Players with < 3 risk factors (“low risk”) were placed in the control group and did not receive one-on-one intervention.

Analysis: The primary outcome measure was proportion of treatment successes, defined as a reduction of ≥ 1 risk factor(s). Secondary outcomes included analysis of within group and between group differences.

Results: Thirteen subjects were treated with one-on-one intervention, with twelve having a reduction of at least 1 risk factor at posttest. The proportion of treatment successes in the intervention group was 0.923 (95%CI 0.640-0.998). The proportion of high risk subjects that became low risk at posttest was 0.846, which was statistically significant (p = 0.003). Within group differences were noted in active straight leg raise (left; p = 0.017), hip external rotation (right, p=0.000; left, p = 0.001) thoracic spine rotation (left; p=0.026), and upper quarter neuromuscular control measures (left inferolateral reach, p = 0.003; left composite, p = 0.016). A statistically significant between group difference was noted in risk factor change from pretest to posttest (p = 0.002), with the median risk factor change in the intervention group and control group being -3 and -1, respectively.

Conclusion: Utilizing one-on-one interventions designed to target evidence-based risk factors is an effective strategy to reduce LE musculoskeletal injury risk factors in high risk individuals.

Digital Object Identifier (DOI)