title: Spine-hip relations add understandings to the pathophysiology of femoro-acetabular impingement: A systematic review.
abstract: Relationship between hip pathoanatomy and symptomatic FAI has been reported to be weak. This is explained by the reciprocal interaction between proximal femur and acetabular anatomies, but potentially also by the individual spine-hip relations (SHR). The key-answer for a complete understanding of the pathophysiology of FAI might lie in the comprehension of the SHRs, which have not yet been fully addressed. Therefore we conducted a systematic review to answer the subsequent questions: Is there any evidence of a relationship between FAI and (1) sagittal pelvic kinematics, (2) pelvic incidence, and (3) types of SHRs? A systematic review of the existing literature utilizing PubMed and Google search engines was performed in December 2016. Only studies published in peer-reviewed journals over the last ten years in either English or French were reviewed. We identified 90 reports, of which 9 met our eligibility criteria. Review of literature shows Caucasian FAI patients have a pelvis with higher anterior tilt, lesser sagittal mobility, and lower pelvic incidence compared to healthy patients. We found no study having assessed the relationship between SHR and FAI. In order to help further investigations at answering questions 3 and 4, we have developed a classification for SHRs. The classification according spino-pelvic parameters allows identifying patient at risk regarding FAI occurrence. Higher anterior pelvic tilt in standing, sitting and squatting positions and lower pelvic incidence have been found to correlate with symptomatic FAI. Because defining the individual SHR might increase the understanding of the pathophysiology of hip impingement, we have developed a classification for SHRs.
  
  
  
  Level IV, systematic review of Level III and IV studies.
authors.affiliation: The MSK Lab, Charing Cross Campus, laboratory Block, London W6 8RP Imperial College, London, United Kingdom. Electronic address: rivierech@gmail.com.
authors.forename: C
authors.initials: C
authors.lastname: Rivière
authors.affiliation: The MSK Lab, Charing Cross Campus, laboratory Block, London W6 8RP Imperial College, London, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Hardijzer
authors.affiliation: Service de chirurgie orthopédique, université Pierre-et-Marie-Curie, hôpital Pitié-Salpêtrière, 47-83, boulevard de l'Hôpital, 75013 Paris, France.
authors.forename: J-Y
authors.initials: JY
authors.lastname: Lazennec
authors.affiliation: Division of orthopaedic surgery, university of Ottawa, the Ottawa hospital, general campus, 501, Smyth road, W1638, K1H 8L6 Ottawa, Ontario, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Beaulé
authors.affiliation: London hip unit, 30, Devonshire street, W1G 6PU Marylebone, London, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Muirhead-Allwood
authors.affiliation: The MSK Lab, Charing Cross Campus, laboratory Block, London W6 8RP Imperial College, London, United Kingdom.
authors.forename: J
authors.initials: J
authors.lastname: Cobb
mesh_terms: D057925:Femoracetabular Impingement / Q000503:physiopathology*; D006621:Hip Joint / Q000503:physiopathology*; D006801:Humans; D016059:Range of Motion, Articular; D013131:Spine / Q000503:physiopathology*
keywords: Classification; Femoro-acetabular impingement; Pelvic incidence; Pelvic kinematics; Spine-hip relation; Spine-hip syndrome