title: Short-term follow up after implantation of a cell-free collagen type I matrix for the treatment of large cartilage defects of the knee.
abstract: OBJECTIVE
  Although there are various new scaffold-based techniques for cartilage regeneration it remains unclear up to which defect size they can be used. The present study reports of a cell-free collagen type I gel matrix for the treatment of large cartilage defects of the knee after a two-year follow-up.
  
  
  METHODS
  Twenty-eight patients with a mean cartilage defect size of 3.71 ± 1.93 cm² were treated with a cell-free collagen type I gel matrix (CaReS-1S®, Arthro Kinetics AG, Krems/Donau, Austria) via a mini-arthrotomy. Clinical outcome was assessed preoperatively and six weeks as well as six, 12 and 24 months after surgery using various clinical outcome scores (IKDC, Tegner, KOOS, VAS). Cartilage regeneration was evaluated via MRI using the MOCART score.
  
  
  RESULTS
  Seventeen male and 11 female patients with a mean age of 34.6 years were included in this study. Significant pain reduction (VAS) could be noted after six weeks already. Patient activity (IKDC, Tegner) could be significantly improved from 12 months on and nearly reached reported pre-operative values. All subject categories of the KOOS except for symptom (swelling) showed significant improvements throughout the study. Constant significant improvements of the mean MOCART score were observed from 12 months on. MR images did not yield any signs of infection or synovitis. After 24 months a complete defect filling could be noted in 24 out of 28 cases with a mainly smooth surface, complete integration of the border zone and homogenous structure of the repaired tissue.
  
  
  CONCLUSIONS
  Cell-free collagen type I matrices appear to be a safe and suitable treatment option even for large cartilage defects of the knee. Results of this study were comparable to the better-established findings for small cartilage defects. Mid- and long-term results will be needed to see if clinical and MR-tomographic outcome can be maintained beyond 24 months.
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany.|Department of Orthopaedics and Traumatology, University Hospital Bonn, Bonn, Germany.
authors: Philip P
authors: PP
authors: Roessler
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors: Bernhard
authors: B
authors: Pfister
authors: Department of Trauma and Orthopaedic Surgery, Paracelsus Medical University, Nürnberg, Germany.
authors: Markus
authors: M
authors: Gesslein
authors: Department of Radiology, University Hospital Marburg, Marburg, Germany.
authors: Jens
authors: J
authors: Figiel
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors: Thomas J
authors: TJ
authors: Heyse
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors: Christian
authors: C
authors: Colcuc
authors: Department of Orthopaedic Surgery, Saarland University, Homburg, Saar, Germany.
authors: Olaf
authors: O
authors: Lorbach
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany. efet@med.uni-marburg.de.
authors: Turgay
authors: T
authors: Efe
authors: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors: Karl F
authors: KF
authors: Schüttler
mesh_terms: D000293:Adolescent; D000328:Adult; D001317:Austria; D002357:Cartilage Diseases / Q000601:surgery*; D002358:Cartilage, Articular / Q000601:surgery*; D024042:Collagen Type I / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome; D014945:Wound Healing; D055815:Young Adult
chemical_list: D024042:Collagen Type I
keywords: Cartilage repair; Cell-free collagen type I; Clinical outcome; Large cartilage defects; MRI; Short-term results