Inclusion Criteria:  Patient aged 18 years or older, having been informed of the research A patient with at least five years of uncemented total hip replacement implanted as a first-line procedure A patient who has been regularly monitored since surgery and for whom all clinical and radiological data are available at the five-year follow-up visit  Exclusion Criteria:  Patient operated for revision History of femoral fracture (pre or per operative) Chronic treatment likely to affect calcium metabolism and ossification Patient under legal protection, guardianship or curatorship A patient who has indicated his or her opposition to the use of his or her medical data (by completing and returning the non-opposition form that will be sent to him or her).