title: Increased Femoral Anteversion Influence Over Surgically Treated Recurrent Patellar Instability Patients.
abstract: OBJECTIVE
  To verify the influence that increased femoral anteversion (FA) has on patients with recurrent patellar instability (RPI) treated by anteromedialization tibial tubercle osteotomy (TTO) combined with medial patellofemoral ligament reconstruction (MPFLR) and to present the midterm outcomes of these patients.
  
  
  METHODS
  From January 2008 to August 2013, skeletally mature patients with RPI and tibial tubercle (TT)-trochlear groove (TG) ≥ 17 mm who underwent anteromedialization TTO combined with MPFLR were evaluated for J sign, patellar glide, apprehension test, increased FA, Caton index, trochlea dysplasia, TT-TG, Kujala, International Knee Documentation Committee subjective knee evaluation form, and Tegner. Increased FA was determined clinically by a difference of more than 30° between hip internal and external rotation, 70° or more of hip internal rotation, and 30° or more of femoral neck anteversion. A subgroup analysis involving increased FA was made.
  
  
  RESULTS
  Forty-eight patients composed the study group. Mean follow-up was 41.5 ± 11.05 months. The J-sign was present in 86% before surgery and none postoperatively (P < .001). All patients had a positive apprehension test or a patellar luxation at the patellar glide test rated as grade 4 before surgery. After surgery, the mean glide was 1.29 ± 0.45 with no apprehension (P < .001). Increased FA was present in 18.7%. Caton index before surgery was 1.11 ± 0.21 and 0.99 ± 0.11 postoperatively (P = .004). Trochlea dysplasia was present in all patients. TT-TG preoperatively was 20.77 ± 2.12 mm and 11.33 ± 1.24 mm postoperatively (P < .001). Functional scores improved preoperatively to postoperatively (P < .001) with Kujala and International Knee Documentation Committee means: 59.08 to 84.37; 52.6 to 85.5, respectively. Tegner preinjury score was 5.4 and postoperatively was 5.2 (P = .01). Increased FA group had worse Kujala compared with the normal FA group and worse Kujala improvement: 77.7 and 85.89 (P = .012), and 21.7 and 26.1, respectively (P < .001).
  
  
  CONCLUSIONS
  Increased FA in patients with RPI had a negative effect on the outcome of anteromedialization TTO combined with MPFLR. Combined anteromedialization TTO and MPFLR had good functional midterm outcomes in treating patients with RPI and TT-TG ≥ 17 mm.
  
  
  METHODS
  Level III, comparative study.
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil. Electronic address: cacarlos66@hotmail.com.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Franciozi
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Luiz Felipe
authors.initials: LF
authors.lastname: Ambra
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Leonardo José Bernardes
authors.initials: LJ
authors.lastname: Albertoni
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Pedro
authors.initials: P
authors.lastname: Debieux
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Fernando Cury
authors.initials: FC
authors.lastname: Rezende
authors.affiliation: Hospital Regional Público do Leste, Paragominas, PA, Brazil.
authors.forename: Mauricio Ayres de
authors.initials: MA
authors.lastname: Oliveira
authors.affiliation: Hospital do Coração, São Paulo, SP, Brazil.
authors.forename: Marcio de Castro
authors.initials: MC
authors.lastname: Ferreira
authors.affiliation: Department of Orthopaedics and Traumatology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Marcus Vinícius Malheiros
authors.initials: MV
authors.lastname: Luzo
mesh_terms: D000328:Adult; D060750:Bone Anteversion / Q000209:etiology*; D005260:Female; D005272:Femur Neck; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery; D008023:Ligaments, Articular / Q000601:surgery; D008297:Male; D010027:Osteotomy / Q000009:adverse effects*; D031222:Patellar Dislocation / Q000601:surgery; D011183:Postoperative Complications; D012008:Recurrence; D013977:Tibia / Q000601:surgery*