Westfälische Wilhelms Universität Surgical Application, biomechanical and first clinical data of a matrix augmented microfracture procedure using chondrotissue Wolf Petersen Klinik für Unfall- Hand und Wiederherstellungschirurgie Westfälische Wilhelms Universität Münster
ACI versus Microfracture? No significant difference in Lysholm und VAS SF 36 significantly better after microfracture Knutsen et al. 2004
ACI versus Microfracture? Not an equal battle Minimal invasive techniques
Arthroscopic techniques Marcacci technique: Erggelet technique: Hyalograft Bioseed C - Easy to perform - Adhesion - Poor fixation strength (larger defects? No shoulder?) - Transfemoral suturing - Good fixation strength - Technically demanding
Surgical Application Smart nail, biodegradable pin (PLLA)
Surgical Application SAMIC Scaffold Augmented Microfracture Chondrotissue Smart nail, biodegradable pin (PLLA) PGA/Hyaluronean acid
SAMIC Microfx Scaffold Guided tissue regeneration Regenerate
Defect size SAMIC Scaffold Augmented Microfracture Specific needle (Karl Storz) Determination of the defect size: 20x10 mm
Scaffold preparation SAMIC Scaffold Augmented Microfracture Cutting of the scaffold Soak the implant in autologous human serum Chondrotissue
Arthroscopic Technique SAMIC Scaffold Augmented Microfracture Debridement Microfracture
Portals SAMIC Scaffold Augmented Microfracture 2. Medial: Matrix 1. Anterolateral: Visualiziation 3. Anteromedial: Pin insertion Three portals
Cannula SAMIC Scaffold Augmented Microfracture Cannula trough the medial portal
Matrix insertion SAMIC Scaffold Augmented Microfracture Chondrotissue
Arthroscopic Technique SAMIC Scaffold Augmented Microfracture Chondrotissue Matrix is held in place with the probe
Arthroscopic Technique SAMIC Scaffold Augmented Microfracture Smart nail 16 mm PLLA Resorbtion time 6-12 month Drilling the hole for the nail
Drilling SAMIC Scaffold Augmented Microfracture Drilling the hole for the nail
Pin insertion SAMIC Scaffold Augmented Microfracture Curl et al. Arthroscopy 1997 Application of the Smart nail
Result SAMIC Scaffold Augmented Microfracture
How many pins? SAMIC Scaffold Augmented Microfracture Two Smart nails 20 x 10 mm >20 mm
Biomechanical data
Biomechanical evaluation 3 dimensional matrix: Chondrotissue, Biotissue, Freiburg Porcine Femur: age 25 (+/- 2) weeks Zelle et al. Arthroscopy 10/2007
Material and Methods Conventional suture technique 4 sutures PDS 6-0 USP (n=10) Zelle et al. Arthroscopy 10/2007
Material and Methods Transosseous suture technique (2-0 Vicryl suture with 3 knots) (n=10) Zelle et al. Arthroscopy 10/2007
Material and Methods Arthroscopic technique with 2 biodegradable pins (16 mm SmartNail, Conmed, Linvatec) (n=10) Zelle et al. Arthroscopy 10/2007
Stiffness Steifigkeit N/mm Transosseous Transossäre Naht Konventionelle Pinfixation Conventional Pin Naht Sig difference conventional suture vs. transosseous suture and pin fixation
Yield load Versagenslast N Transossäre Naht Konventionelle Naht Pinfixation Transosseous Conventional Pin Sig difference conventional suture vs. transosseous suture and pin fixation
Max. load Maximale Versagenslast N Transosseous Transossäre Naht Konventionelle Conventional Pinfixation Pin Naht Sig difference conventional suture vs. transosseous suture and pin fixation
Failure mode Conventional suture n=10 Transosseous suture n=10 Pin fixation n=10
Conclusion Strctural properties of arthroscopic matrix fixation techniques are significantly better than the conventional suture technique
First clinical data 5 patients since March 2007 Age: 28-46 years Defect size: 2.4-5.5 cm² 4x medial femoral condyle 1x lateral femoral condyle Surgical time: mean 29 Minutes
First clinical data Rehab: - 6 weeks partial weight bearing No adverse effects: - no infection - no prolonged effusion - no allergicreaction
Prospective randomized clinical trial 5 centers W. Petersen Münster Germany D. Fritschy Géneve Switzerland R. Verdonk Gent Belgium C. Erggelet Zurich Switzerland Zorzi Verona Italy 30 Patients Microfx 15 Patients AMIC (Chondrotissue) 15 Patients FU 12 weeks, 1 year, 2 years MRI, SF 36, VAS walking, VAS daily living activities, Tegner Score
SAMIC Scaffold Augmented Microfracture Result presentation on ICRS 2009 in Miami?