title: Sexual activity after total hip arthroplasty: a motion capture study.
abstract: Relative risk of impingement and joint instability during sexual activities after total hip arthroplasty (THA) has never been objectively investigated. Hip range of motion necessary to perform sexual positions is unknown. A motion capture study with two volunteers was performed. 12 common sexual positions were captured and relevant hip joint kinematics calculated. The recorded data were applied to prosthetic hip 3D models to evaluate impingement and joint instability during motion. To explore the effect of acetabular component positioning, nine acetabular cup positions were tested. Four sexual positions for women requiring intensive flexion (> 95°) caused prosthetic impingements (associated with posterior instability) at 6 cup positions. Bony impingements (associated with anterior instability) occurred during one sexual position for men requiring high degree of external rotation (> 40°) combined with extension and adduction at all cup positions. This study hence indicates that some sexual positions could be potentially at risk after THA, particularly for women.
authors.affiliation: Medical Research Department, Artanim Foundation, Geneva, Switzerland.
authors.forename: Caecilia
authors.initials: C
authors.lastname: Charbonnier
authors.affiliation: Medical Research Department, Artanim Foundation, Geneva, Switzerland.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Chagué
authors.affiliation: Medacta International SA, Lugano, Switzerland.
authors.forename: Matteo
authors.initials: M
authors.lastname: Ponzoni
authors.affiliation: Medacta International SA, Lugano, Switzerland.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Bernardoni
authors.affiliation: Department of Surgery, Orthopedics and Trauma Service, University Hospitals of Geneva, Geneva, Switzerland.
authors.forename: Pierre
authors.initials: P
authors.lastname: Hoffmeyer
authors.affiliation: Department of Surgery, Orthopedics and Trauma Service, University Hospitals of Geneva, Geneva, Switzerland.
authors.forename: Panayiotis
authors.initials: P
authors.lastname: Christofilopoulos
mesh_terms: D000328:Adult; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D001696:Biomechanical Phenomena; D003075:Coitus / Q000502:physiology*; D003198:Computer Simulation; D005260:Female; D057925:Femoracetabular Impingement / Q000175:diagnosis* / Q000209:etiology; D006621:Hip Joint / Q000502:physiology*; D006622:Hip Prosthesis; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D011187:Posture; D016059:Range of Motion, Articular
keywords: cup positioning; impingement; joint instability; motion capture; sexual activity; total hip arthroplasty