title: Return to sport after the surgical management of articular cartilage lesions in the knee: a meta-analysis.
abstract: OBJECTIVE
  Optimal surgical treatment of chondral defects in an athletic population remains highly controversial and has yet to be determined. The purpose of this review was to (1) report data on return to sport and (2) compare activity and functional outcome measures following various cartilage restoration techniques.
  
  
  METHODS
  A comprehensive review was performed for studies with return-to-sport outcomes after microfracture (MFX), osteochondral autograft transfer (OAT), osteochondral allograft transplantation (OCA), and autologous chondrocyte implantation (ACI). All studies containing return-to-sport participation with minimum 2-year post-operative activity-based outcomes were included. A meta-analysis comparing rate of return to sport between each surgical intervention was conducted using a random-effects model.
  
  
  RESULTS
  Forty-four studies met inclusion criteria (18 Level I/II, 26 Level III/IV). In total, 2549 patients were included (1756 M, 793 F) with an average age of 35 years and follow-up of 47 months. Return to sport at some level was 76 % overall, with highest rates of return after OAT (93 %), followed by OCA (88 %), ACI (82 %), and MFX (58 %). Osteochondral autograft transfer showed the fastest return to sports (5.2 ± 1.8 months) compared to 9.1 ± 2.2 months for MFX, 9.6 ± 3.0 months for OCA and 11.8 ± 3.8 months for ACI (P < 0.001). A meta-regression was conducted due to heterogeneity in preoperative factors such as patient age, lesion size, and preoperative Tegner score. None of these factors were found to be significant determinants for rate of return to sport.
  
  
  CONCLUSIONS
  In conclusion, in this meta-analysis of 2549 athletes, cartilage restoration surgery had a 76 % return to sport at mid-term follow-up. Osteochondral autograft transfer offered a faster recovery and appeared to have a higher rate of return to preinjury athletics, but heterogeneity in lesion size, athlete age, and concomitant surgical procedures are important factors to consider when assessing individual athletes. This study reports on the rate of return to sport in athletes undergoing various procedures for symptomatic chondral defects.
  
  
  METHODS
  IV.
authors.affiliation: Department of Orthopedic Surgery and Sports Medicine, Mayo Clinic, Rochester, MN, USA. Krych.Aaron@Mayo.edu.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Krych
authors.affiliation: Department of Orthopedic Surgery and Sports Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Ayoosh
authors.initials: A
authors.lastname: Pareek
authors.affiliation: Department of Orthopedic Surgery and Sports Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Alexander H
authors.initials: AH
authors.lastname: King
authors.affiliation: Department of Orthopedic Surgery and Sports Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Nick R
authors.initials: NR
authors.lastname: Johnson
authors.affiliation: Department of Orthopedic Surgery and Sports Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stuart
authors.affiliation: Department of Orthopedic Surgery, Institute for Cartilage Repair, Hospital for Special Surgery, New York, NY, 10021, USA.
authors.forename: Riley J
authors.initials: RJ
authors.lastname: Williams
mesh_terms: D001265:Athletic Injuries / Q000601:surgery*; D002358:Cartilage, Articular / Q000293:injuries* / Q000601:surgery; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery*; D015233:Models, Statistical; D019637:Orthopedic Procedures / Q000379:methods; D020127:Recovery of Function; D000068958:Return to Sport; D016896:Treatment Outcome
keywords: Autologous chondrocyte implantation; Cartilage; Microfracture; Osteochondral allograft transplantation; Osteochondral autograft transfer; Return to sport