title: Hypertrophy of the tensor fascia lata muscle as a complication of total hip arthroplasty.
abstract: BACKGROUND
  Hypertrophy of the tensor fascia lata muscle (HTFLM) is a rare complication after total hip arthroplasty (THA) and is a potential source of pain, palpable mass, or both.
  
  
  METHODS
  We retrospectively analyzed 1285 primary THAs and 482 THA revisions (THAR) performed at our center from 2008 to 2014. Among these, five patients had HTFLM (average age 68.8 years). The type of surgery and symptoms were evaluated, as were imaging studies (CT or MRI) of both hips (10 hips), and functional outcomes with the Merle d'Aubigné score.
  
  
  RESULTS
  The suspected diagnosis was established at an average of 30.2 months after surgery. Four cases occurred after THA and one case after THAR. A modified Hardinge approach was used in four cases and a Röttinger approach in one case. Two cases had pain and palpable mass in the trochanteric region and three cases only pain. The asymmetric HTFLM of the THA side against the nonsurgical side was confirmed by measuring the cross section of the tensor fascia lata muscle on imaging. The sartorius muscle was measured for reference in each case. The Merle d'Aubigne scale had a mean value of 16.6 (range 13-18) at 38 months after the procedure.
  
  
  CONCLUSIONS
  HTFLM after THA is a benign condition that could be mistaken for a tumor when presenting as a palpable mass. We propose that it should be considered in the differential diagnosis of pain in the lateral aspect of hips that have previously undergone THA.
authors.affiliation: Hip Unit, Department of Orthopaedic Surgery and Traumatology, Hospital Clinic, University of Barcelona, Barcelona, Spain. jmleon42@gmail.com.|Hospital Clínic de Barcelona, University of Barcelona, C/ Villarroel 170, 08036, Barcelona, Spain. jmleon42@gmail.com.
authors.forename: Juan Miguel
authors.initials: JM
authors.lastname: Rodríguez-Roiz
authors.affiliation: Hip Unit, Department of Orthopaedic Surgery and Traumatology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Guillem
authors.initials: G
authors.lastname: Bori
authors.affiliation: Department of Radiology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Tomas
authors.affiliation: Hip Unit, Department of Orthopaedic Surgery and Traumatology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Jenaro A
authors.initials: JA
authors.lastname: Fernández-Valencia
authors.affiliation: Department of Radiology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Ana Isabel
authors.initials: AI
authors.lastname: García-Díez
authors.affiliation: Department of Radiology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Pomés
authors.affiliation: Hip Unit, Department of Orthopaedic Surgery and Traumatology, Hospital Clinic, University of Barcelona, Barcelona, Spain.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Garcia
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D005260:Female; D006801:Humans; D006984:Hypertrophy / Q000209:etiology / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology*; D010149:Postoperative Pain / Q000209:etiology; D011183:Postoperative Complications / Q000473:pathology; D012189:Retrospective Studies; D061665:Time-to-Treatment; D014057:Tomography, X-Ray Computed
keywords: Fascia lata muscle; Hypertrophy; Painful hip arthroplasty; Soft tissue tumor