title: Anatomic medial patellofemoral ligament reconstruction using patellar suture anchor fixation for recurrent patellar instability.
abstract: OBJECTIVE
  The purpose of this study was to prospectively evaluate clinical and radiographic outcomes following anatomic medial patellofemoral ligament (MPFL) reconstruction using patellar suture anchor fixation for recurrent patellar instability.
  
  
  METHODS
  Twenty patients (20 knees) were enrolled in this study. The median age was 21 years, and the median follow-up was 34.5 months. Reconstruction was performed using a hamstring autograft fixed with two suture anchors at native patellar site of the MPFL. No patient had undergone additional medial tibial tuberosity transfer. Clinical scores (Kujala, Lysholm, and Tegner score) and apprehension test were completed preoperatively and at the follow-up. Preoperative and follow-up radiographic assessments included modified Insall-Salvati ratio, congruence angle, and lateral patellofemoral angle.
  
  
  RESULTS
  The preoperative Kujala and Lysholm scores were 52.6±12.4 and 49.2±10.7, and at follow-up visits, corresponding values were 90.9±4.5 (p<0.001) and 90.9±5.2 (p<0.001). Tegner score increased from 3.0 (range 1-4) to 5.0 (range 4-7) (p<0.001). The apprehension test was positive in all patients preoperatively, but only positive in one patient at follow-up. All radiographic assessments were significantly improved; modified Insall-Salvati index (from 1.75 to 1.65) (p=0.002), congruence angle (from 6.3° to -7.0°) (p<0.001), and lateral patellofemoral angle (from 2.1° to 4.9°) (p=0.008). No patient experienced a patellar fracture or redislocation.
  
  
  CONCLUSIONS
  These results are comparable to those of bone tunnel techniques reported in the literature. This study shows that anatomic MPFL reconstruction using two suture anchors is a reliable treatment option.
  
  
  METHODS
  Case series with no comparison group, Level IV.
authors.affiliation: Department of Orthopaedic Surgery, Dongtan Sacred Heart Hospital, Hallym University College of Medicine, 40, Seokwoo-dong, Hwaseong, Gyeonggi-do, 445-170, Republic of Korea.
authors.forename: Si Young
authors.initials: SY
authors.lastname: Song
authors.forename: In Sung
authors.initials: IS
authors.lastname: Kim
authors.forename: Ho Geun
authors.initials: HG
authors.lastname: Chang
authors.forename: Jae-Hyuk
authors.initials: JH
authors.lastname: Shin
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Seo
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000601:surgery*; D007718:Knee Injuries / Q000601:surgery; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D018482:Muscle, Skeletal / Q000637:transplantation; D010329:Patella / Q000000981:diagnostic imaging / Q000601:surgery*; D031222:Patellar Dislocation / Q000601:surgery*; D057071:Patellofemoral Joint / Q000601:surgery*; D011446:Prospective Studies; D011859:Radiography; D019651:Plastic Surgery Procedures; D053441:Suture Anchors; D013977:Tibia / Q000601:surgery; D014182:Transplantation, Autologous; D055815:Young Adult