title: Does severity of femoral trochlear dysplasia affect outcome in patellofemoral instability treated by medial patellofemoral ligament reconstruction and anterior tibial tuberosity transfer?
abstract: BACKGROUND
  Medial patellofemoral ligament (MPFL) reconstruction associated to anterior tibial tuberosity transfer (ATTT) is recommended in objective patellofemoral instability (PFI). Efficacy, however, has not been precisely determined in trochlear dysplasia with spur. A case-control study was performed in a PFI population, comparing groups with trochlear dysplasia with and without spur (S+ vs. S-) to assess the impact of trochlear dysplasia on (1) patellofemoral stability, (2) functional results and complications, and (3) patellofemoral cartilage status on MRI.
  
  
  OBJECTIVE
  Trochlear spur does not affect outcome in PFI managed by MPFL reconstruction and ATTT.
  
  
  METHODS
  Twenty-eight knees (26 patients) with PFI were analyzed retrospectively and divided into 2 groups of 14 knees each according to presence of trochlear spur (S+ vs. S-). All 28 knees had undergone ATTT and MPFL reconstruction by semitendinosus autograft. Results were assessed on Lille and IKDC functional scores, and cartilage status was determined on MRI at last follow-up.
  
  
  RESULTS
  At a mean 24 months' follow-up (range, 12-52 months), there was no recurrence of dislocation. IKDC and Lille scores tended to improve in both groups, although the only significant improvement was in IKDC score (S- gain, 21.3±16; S+ gain, 18.1±14) (P=0.01). IKDC scores at last follow-up were better in the S+ than S- group (79±19 [range, 21-92] vs. 68±13 [range, 35-84], respectively; P=0.012). Lille scores showed no significant inter-group differences in mean gain (P=0.492) or mean value (P=0.381). The S+ group showed more cartilage lesions (n=14/14 knees, including 12/14 with grade≥2 lesions) than the S- group (n=9/14 knees, all grade≤2).
  
  
  CONCLUSIONS
  MPFL reconstruction with ATTT provided good short-term patellofemoral stability independently of the severity of trochlear dysplasia. Functional results and gain on IKDC, however, were poorer in case of dysplasia with trochlear spur. This is probably due to cartilage lesions, observed more frequently pre- and post-operatively in the spur group, especially as there was no significant difference in Lille Score, which highlights stability.
  
  
  METHODS
  III, retrospective case-control study.
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France. Electronic address: greg.moitrel@gmail.com.
authors.forename: G
authors.initials: G
authors.lastname: Moitrel
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France.
authors.forename: T
authors.initials: T
authors.lastname: Roumazeille
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Arnould
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France.
authors.forename: H
authors.initials: H
authors.lastname: Migaud
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Putman
authors.affiliation: Laboratoire de biostatistique, pôle de santé publique, CHRU de Lille, pôle de santé publique, 154, rue du Docteur-Yersin, Lille, France.
authors.forename: N
authors.initials: N
authors.lastname: Ramdane
authors.affiliation: Université Lille Nord de France, 59000 Lille, France; Service d'orthopédie, hôpital Salengro, CHRU de Lille, place de Verdun, 59037 Lille cedex, France.
authors.forename: G
authors.initials: G
authors.lastname: Pasquier
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D057071:Patellofemoral Joint / Q000601:surgery*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013977:Tibia / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult
keywords: Anterior tibial tuberosity transfer; Knee; Medial patellofemoral ligament reconstruction; Patellar instability; Trochlear dysplasia