title: Trochleaplasty for patellar instability due to trochlear dysplasia: A minimum 2-year clinical and radiological follow-up of 19 knees.
abstract: BACKGROUND
  Recurrent patellar dislocation may be associated with trochlear dysplasia. Trochleaplasty is a surgical procedure which strives to deepen the trochlear groove. We evaluated the clinical and radiological effect of trochleaplasty after a minimum follow-up of 2 years.
  
  
  METHODS
  We examined 19 knees in 16 patients at a mean of 3 years after trochleaplasty. Postoperatively, a subjective questionnaire, a Kujala score, and tests for potential patellar redislocation and apprehension were evaluated. On radiographs we evaluated the preoperative and postoperative crossing sign, trochlear depth, trochlear bump, and patellar height. On CT scans, the pre- and postoperative tibial tuberosity to trochlear groove distance (TTTG) and the patellar inclination angle were measured.
  
  
  RESULTS
  16 of 19 knees improved subjectively. The Kujala score increased from 56 to 80 points at the latest follow-up. None of the patients sustained a redislocation. 5 patients had medial parapatellar tenderness, including 4 with persistent apprehension. Radiological signs of trochlear dysplasia were corrected.
  
  
  CONCLUSIONS
  Patellofemoral instability with underlying trochlear dysplasia can be treated successfully by trochleaplasty.
authors.affiliation: Department of Orthopedic Surgery, University Hospital Balgrist Zurich, Forchstr. 340, CH-8008, Zurich, Switzerland.
authors.forename: Philip B
authors.initials: PB
authors.lastname: Schöttle
authors.forename: Sandro F
authors.initials: SF
authors.lastname: Fucentese
authors.forename: Christian
authors.initials: C
authors.lastname: Pfirrmann
authors.forename: Heinz
authors.initials: H
authors.lastname: Bereiter
authors.forename: Jose
authors.initials: J
authors.lastname: Romero
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery; D008297:Male; D010329:Patella / Q000000981:diagnostic imaging / Q000601:surgery*; D031222:Patellar Dislocation / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D011795:Surveys and Questionnaires; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome