Characterization of pincer-type Hip impingement in professional women's ice hockey players

Femoroacetabular impingement (FAI) appears common in ice hockey, but there is a lack of data examining pincer-type impingement in women's ice hockey athletes. The objective of this study was to assess the prevalence of pincer-type impingement in National Women's Hockey League (NWHL) athletes. Our hypothesis was that there would be an increased prevalence of pincer impingement in these athletes.

Data were gathered for a team of NWHL players, and age, gender, and body mass index (BMI) matched controls were also retrospectively collected. All subjects were above 18 years of age. Control patients were excluded if they had undergone prior hip surgery, were greater than age 30, or had BMI greater than 35. Radiographs of both groups were assessed for lateral center edge angle (LCEA), Tönnis angle, and crossover sign. Tönnis angle <0 or LCEA >40 degrees was considered pincer morphology. An alpha angle >55 degrees was considered cam morphology.

Thirty-seven NWHL players and 37 female controls were included. Overall 32% of the players had a pincer lesion in either hip based on LCEA, 8% had a Tönnis angle <0, and 22% had a crossover sign in either hip compared to 9%, 19%, and 13% for the controls, respectively. None of these findings were significantly different between the groups (p > 0.05). An alpha angle ≥55 degrees in either hip was found in 84% of players, but lateral Dunn images for alpha angle measurements were not available for the control group.

Pincer-type morphology and crossover signs were present in a larger portion of NWHL players than has been reported in the general population, but these findings were not statistically different than in the control group. Cam-type morphology was even more prevalent in these athletes and may be related to age at menarche due impingement at the physis prior to closure.