Objective
To describe the injury mechanisms and magnetic resonance imaging (MRI) findings in acute hamstring injuries of male soccer players using a systematic video analysis.
Design
Descriptive case series study of consecutive acute hamstring injuries from September 2017 to January 2022.
Setting
Two specialized sports medicine hospitals.
Participants
Professional male soccer players aged between 18-40 years, referred for injury assessment within 7 days after an acute hamstring injury, with an available video footage of the injury and positive finding on MRI.
Independent variables
Hamstring injury mechanisms (specific scoring based on standardized models) in relation to hamstring muscle injury MRI findings.
Main outcome measures
Hamstring injury mechanism (playing situation, player/opponent behavior, movement, and biomechanical body positions), MRI injury location.
Results
14 videos of acute hamstring injuries in 13 professional male soccer players were analyzed. Three different injury mechanisms were seen: mixed-type (both sprint-related and stretch-related, 43%), stretch-type (36%), and sprint-type (21%). Most common actions during injury moments were change of direction (29%), kicking (29%), and running (21%). Most injuries occurred at high or very high horizontal speed (71%) and affected isolated proximal biceps femoris (36%). Most frequent body positions at defined injury moments were neutral trunk (43%), hip flexion 45°-90° (57%), and knee flexion <45° (93%). MRI findings showed that 79% were isolated single-tendon injuries.
Conclusions
According to video analysis, most hamstring injuries in soccer occur during high-speed movements. Physicians should suspect proximal and isolated single-tendon – most often biceps femoris - hamstring injury, if represented injury mechanisms are seen during game play. In addition to sprinting and stretching, also mixed-type injury mechanisms occur.