title: Incidence of greater trochanteric pain syndrome in patients suspected for femoroacetabular impingement evaluated using magnetic resonance arthrography of the hip.
abstract: OBJECTIVE
  We evaluated the incidence of greater trochanter pain syndrome (GTPS) in patients who underwent magnetic resonance arthrography (MRA) of the hip for a suspected femoroacetabular impingement (FAI) syndrome.
  
  
  METHODS
  Hip MRA performed at our institution (3/2012-1/2014) were reviewed. The absence/presence of FAI (cam, pincer, and mixed) was noted. GTPS diagnosis was based on gluteus medius/minimus tendinopathy/tears, trochanteric bursitis, fascia lata thickening, and trochanter bone oedema/erosion. Subgroup analysis for age (under/over 40 years) and FAI type (cam, pincer, and mixed) was also performed.
  
  
  RESULTS
  N = 189 patients were included (n = 125 males; age 39 ± 12 years). FAI was diagnosed in n = 133 (70, 4%): cam type, n = 85 (63, 9%); pincer type, n = 22 (16, 6%); and mixed type, n = 26 (19, 5%). N = 72 patients (38.1%) had tendinopathy, n = 14 (7.4%) had trochanter erosion, n = 31 (16.4%) had bursitis, n = 4 had bone oedema (2.1%), and n = 3 (1.6%) had fascia lata thickening, resulting in GTPS diagnosis in n = 74 patients (39.2%). The association of normal hip morphology/GTPS was significantly higher (P = 0.023) than that of FAI/GTPS. Under 40 years, GTPS incidence was higher in patients with normal hip and pincer-type FAI (P = 0.028). Over 40 years, no difference between patients with/without FAI (P = 0.119) was seen.
  
  
  CONCLUSIONS
  GTPS was more frequently observed in patients with normal hip morphology than in patients with FAI, particularly in patients under 40.
authors.affiliation: Unità Operativa di Radiologia/Diagnostica per Immagini con Servizio di Radiologia Interventistica, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161, Milan, Italy.
authors.forename: Grazia
authors.initials: G
authors.lastname: Pozzi
authors.affiliation: Dipartimento di Radiologia, IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano, Italy. eziolanza@gmail.com.
authors.forename: Ezio
authors.initials: E
authors.lastname: Lanza
authors.affiliation: Unità di Ortopedia e Traumatologia, ASST-Papa Giovanni XXIII, Piazza OMS 1, 24127, Bergamo, Italy.
authors.forename: Cleber Garcia
authors.initials: CG
authors.lastname: Parra
authors.affiliation: Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Via Festa del Perdono 7, 20122, Milan, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Merli
authors.affiliation: Unità Operativa di Radiologia/Diagnostica per Immagini con Servizio di Radiologia Interventistica, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161, Milan, Italy.|Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy.
authors.forename: Luca Maria
authors.initials: LM
authors.lastname: Sconfienza
authors.affiliation: Unità Operativa di Radiologia/Diagnostica per Immagini con Servizio di Radiologia Interventistica, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161, Milan, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Zerbi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002062:Bursitis / Q000000981:diagnostic imaging; D002648:Child; D005260:Female; D057925:Femoracetabular Impingement / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005269:Femur / Q000000981:diagnostic imaging*; D006801:Humans; D015994:Incidence; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D013577:Syndrome
keywords: Femoroacetabular impingement; Greater trochanter pain syndrome; Hip; Magnetic resonance arthrography; Trochanteric bursitis