The effect of pelvic tilt and cam on hip range of motion in young elite skiers and nonathletes

Anna Swärd Aminoff,1 Cecilia Agnvall,2,3 Carl Todd,1 Páll Jónasson,4 Mikael Sansone,1 Olof Thoreson,1 Leif Swärd,1 Jon Karlsson,1 Adad Baranto1 1Department of Orthopaedics, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, and Sahlgrenska University Hospital, Gothenburg, Sweden; 2Sports Medicine Åre, Åre, Sweden; 3Åre Ski Academy, Åre, Sweden; 4Orkuhúsið Orthopedic Clinic, Reykjavik, Iceland Background: Current knowledge of the effect of changes in posture and the way cam morphology of the hip joint may affect hip range of motion (ROM) is limited. Purpose: To determine the effect of changes in pelvic tilt (PT) on hip ROM and with/without the presence of cam. Study design: This was a cross-sectional study. Materials and methods: The hip ROM of 87 subjects (n=61 young elite skiers, n=26 nonathletes) was examined using a goniometer, in three different seated postures (flexed, neutral, and extended). The hips of the subjects were further subgrouped into cam and no-cam morphology, based on the magnetic resonance imaging findings in the hips. Results: There was a significant correlation between the hip ROM and the seated posture in both extended and flexed postures compared with the neutral posture. There was a significant decrease in internal hip rotation when the subjects sat with an extended posture with maximum anterior PT (p