Groin and Abdominal Strain Injuries in the National Hockey League

OBJECTIVE: To analyze groin and abdominal strain injuries retrospectively among elite male hockey players in the National Hockey League (NHL) over six seasons of play (1991/92 to 1996/97). DESIGN: Retrospective case series design. SETTING: The NHL. PARTICIPANTS: The NHL participants were an inclusive sample of 7,050 NHL hockey players who played in the NHL from the 1991/92 to the 1996/97 seasons. A subset of 2,600 NHL hockey players who played from the 1995/96 to the 1996/97 seasons was further analyzed. MAIN OUTCOME MEASURES: The injury definition for groin/abdominal strain injury included any injury recorded as a muscle strain injury involving a muscle in any of the abdominal, hip flexor, or hip adductor muscle groups. Femoral, abdominal, and inguinal hernias were also included. Cumulative incidence rates over six seasons of play in the NHL and incidence densities over two seasons of play in the NHL are reported. Specific injury parameters examined included muscle region, time in season, type of session, reinjury, time period in session, position of play, player's experience, mechanism of injury, and time loss. RESULTS: A total of 617 groin/abdominal strain injuries were reported in the NHL over six seasons of play. The cumulative incidence rate in the NHL increased over 6 years of play from 12.99 injuries/100 players/year in the 1991/92 season to 19.87 injuries/100 players/year in the 1996/97 season. The rate of increase was 1.32 (95% confidence interval -0.58, 3.21) injuries/100 players/year. The incidence density of groin/abdominal injury during NHL training camp was five times that during the regular season and 20 times that during the postseason. The incidence density in the NHL during games was six times that during practice. The majority of injuries reported were adductor groin muscle strains. The proportion of injuries reported that were recurrent was 23.5%. There was no significant difference in proportion of injuries reported by time period within a session. The mechanism of injury recorded was noncontact in nature in >90% of injuries reported. Mean time loss due to injury was significantly greater for abdominal injuries (10.59 sessions) than for groin injuries (6.59 sessions). A conservative estimate of the impact of groin/abdominal injury on each NHL team is a game loss of 25 player games/year. CONCLUSION: The impact of groin and abdominal strain injury at an elite level of play in hockey is significant and increasing. Future research in this area is needed to identify risk factors and potentially implement prevention strategies to reduce groin and abdominal strain injury at all levels of play.