title: Surgical treatment of patellofemoral instability using trochleoplasty or MPFL reconstruction: a systematic review.
abstract: OBJECTIVE
  Trochleoplasty and reconstruction of the medial patellofemoral ligament (MPFL) are among the most commonly performed surgical treatments in patients with patellofemoral instability. The primary purpose of the study was to perform a systematic literature review on trochleoplasty in the treatment of patients with patellofemoral instability. The secondary purpose was to compare the outcomes with those seen in patients treated after reconstruction of the MPFL.
  
  
  METHODS
  A standardised search on search engines was performed. All observational and experimental studies dealing with trochleoplasty were then obtained and reviewed in a consensus meeting. Fifteen articles out of 1543 were included and analysed using the CASP appraisal scoring system. Twenty-five studies on MPFL reconstruction were obtained for comparison. The clinical and radiological outcomes were statistically analysed.
  
  
  RESULTS
  Both treatment groups showed significant improvement in outcomes from pre- to post-operatively. The mean post-operative Kujala and the Lysholm scores significantly increased in both groups when compared to preoperatively (trochleoplasty group: Kujala 61.4-80.8 and Lysholm 55.5-78.5; MPFL group: Kujala 46.9-88.8 and Lysholm 59.9-91.1). Post-operatively a positive apprehension test was found in 20 and 8 % of the trochleoplasty and MPFL groups, respectively. No significant differences in redislocation (2 %) and subluxation (5-6 %) rates were found.
  
  
  CONCLUSIONS
  This systematic review showed that both trochleoplasty and MPFL reconstruction are able to deliver good clinical outcomes with stable patellofemoral joints.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland, 4101, Bruderholz, Switzerland.
authors.forename: Enrique Adrian
authors.initials: EA
authors.lastname: Testa
authors.affiliation: Department of Orthopaedic Surgery, Universitäts-Kinderspital Beider Basel, Basel, Switzerland.
authors.forename: Carlo
authors.initials: C
authors.lastname: Camathias
authors.affiliation: Amsler Consulting, Basel, Switzerland.
authors.forename: Felix
authors.initials: F
authors.lastname: Amsler
authors.affiliation: Department of Orthopaedic Surgery, Sonnenhof, Berne, Switzerland.
authors.forename: Philipp
authors.initials: P
authors.lastname: Henle
authors.affiliation: Center of Biomechanics, CMBE, University of Basel, Basel, Switzerland.
authors.forename: Niklaus F
authors.initials: NF
authors.lastname: Friederich
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland, 4101, Bruderholz, Switzerland. michael.hirschmann@ksbl.ch.
authors.forename: Michael Tobias
authors.initials: MT
authors.lastname: Hirschmann
mesh_terms: D000328:Adult; D005260:Female; D005269:Femur / Q000601:surgery*; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery*; D007593:Joint Instability / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D057071:Patellofemoral Joint / Q000601:surgery*
keywords: MPFL reconstruction; Medial patellofemoral ligament; Patellofemoral instability; Trochlear dysplasia; Trochleoplasty