title: Patellofemoral full-thickness chondral defects treated with second-generation autologous chondrocyte implantation: results at 5 years' follow-up.
abstract: BACKGROUND
  Patellofemoral lesions represent a very troublesome condition to treat for orthopaedic surgeons; however, second-generation autologous chondrocyte implantation (ACI) seems to offer an interesting treatment option with satisfactory results at short-term follow-up.
  
  
  OBJECTIVE
  Hyaluronan-based scaffold seeded with autologous chondrocytes is a viable treatment for the damaged articular surface of the patellofemoral joint.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  Among a group of 38 patients treated for full-thickness patellofemoral chondral lesions with second-generation ACI, we investigated 34 who were available for final follow-up at 5 years. These 34 had chondral lesions with a mean size of 4.45 cm(2). Twenty-one lesions were located on the patella, 9 on the trochlea, and 4 patients had multiple lesions: 3 had patellar and trochlear lesions, and 1 had patellar and lateral femoral condyle lesions. Twenty-six lesions (76.47%) were classified as International Cartilage Repair Society (ICRS) grade IV A or B, 5 lesions (14.70%) were grade IIIC, and 3 (8.82%) were lesions secondary to osteochondritis dissecans (OCD). Results were evaluated using the International Knee Documentation Committee (IKDC) 2000 subjective and objective scores, EuroQol (EQ) visual analog scale (VAS), and Tegner scores at 2 and 5 years. Eight patients had second-look arthroscopy and biopsies.
  
  
  RESULTS
  All the scores used demonstrated a statistically significant improvement (P < .0005) at 2 and 5 years' follow-up. Objective preoperative data improved from 8 of 34 (23.52%) normal or nearly normal knees to 32 of 34 (94.12%) at 2 years and 31 of 34 (91.17%) at 5 years after transplantation. Mean subjective scores improved from 46.09 points preoperatively to 77.06 points 2 years after implantation and 70.39 at 5 years. The Tegner score improved from 2.56 to 4.94 and 4.68, and the EQ VAS improved from 56.76 to 81.47 and 78.23 at 2 and 5 years' follow-up, respectively. A significant decline of IKDC subjective and Tegner scores was found in patients with multiple and patellar lesions from 2 to 5 years' follow-up. Second-look arthroscopies in 8 cases revealed the repaired surface to be nearly normal with biopsy samples characterized as hyaline-like in appearance.
  
  
  CONCLUSIONS
  Hyaluronan-based scaffold seeded with autologous chondrocytes can be a viable treatment for patellofemoral chondral lesions.
authors.affiliation: Orthopaedic Arthroscopic Surgery International Bioresearch Foundation, 24 Via Amadeo GA, Milan 20133, Italy. sportmd@tin.it
authors.forename: Alberto
authors.initials: A
authors.lastname: Gobbi
authors.forename: Elizaveta
authors.initials: E
authors.lastname: Kon
authors.forename: Massimo
authors.initials: M
authors.lastname: Berruto
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Filardo
authors.forename: Marco
authors.initials: M
authors.lastname: Delcogliano
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Boldrini
authors.forename: Lyndon
authors.initials: L
authors.lastname: Bathan
authors.forename: Maurilio
authors.initials: M
authors.lastname: Marcacci
mesh_terms: D000293:Adolescent; D000328:Adult; D002357:Cartilage Diseases / Q000473:pathology*; D002358:Cartilage, Articular / Q000601:surgery; D019902:Chondrocytes / Q000637:transplantation*; D046789:Chondromalacia Patellae / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D010147:Pain Measurement; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds; D014182:Transplantation, Autologous; D055815:Young Adult