title: Component version in modular total hip revision.
abstract: Morphologic changes of the proximal femur make revision total hip arthroplasty challenging. Metaphyseal retroversion and diaphyseal varus are common in this scenario. Twenty-one total hip revisions using a modular femoral prosthesis were examined by obtaining three radiographs (A/P, surgical lateral, and true lateral of the femur) to assemble CAD models for determining the range of modular component positioning. An average of femoral neck anteversion was observed. Seventeen of 21 cases (81%) had retroverted metaphyseal segments (-23.2 degrees +/-17.4 degrees ) and/or varus stems (-32.1 degrees +/-13.0 degrees ). Neck anteversion averaged 21.4 degrees (+/-10.0 degrees ). One of 21 cases (5%) resulted in component orientation similar to a non-modular prosthesis. Modular components provide options to accommodate proximal femoral remodeling not afforded by monobloc stems in total hip revision surgery.
authors.affiliation: Division of Orthopaedics and Rehabilitation, Southern Illinois University School of Medicine Springfield, IL 62794-9679, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Kopec
authors.forename: Aaron
authors.initials: A
authors.lastname: Pemberton
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Milbrandt
authors.forename: Gordon
authors.initials: G
authors.lastname: Allan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000379:methods*; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000601:surgery*; D016723:Bone Remodeling; D005264:Femoral Fractures / Q000601:surgery; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D008875:Middle Aged; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000601:surgery; D011859:Radiography; D012086:Reoperation / Q000295:instrumentation / Q000379:methods; D012189:Retrospective Studies