Corresponding cartilage lesion medial patella and trochlea by Dr. Matthias Steinwachs

Articular cartilage lesions caused by trauma, are a common pathology of the knee joint in young patients resulting in pain and function loss. In a retrospective analysis of 25,124 knee arthroscopy patients, chondral lesions were found in 60% of them. A total of 7% of all patients aged less than 40, and 9% under the age of 50 years, showed 1 to 3 localized grade III or IV cartilage defects. Full-thickness articular cartilage defects only have limited regenerative potential, and spontaneous healing is unlikely. Surgical techniques include the following:

  • Palliative options including debridement and lavage.
  • Reparative options including drilling/microfracture (MFx) to stimulate migration of bone marrow cells into the cartilage defect.
  • Reconstructive options including osteochondral autograft transfer system (OATS®) and osteochondral allograft transplantation.
  • Restorative options including autologous chondrocyte implantation (ACI®).

This case is treated with the microfracture technique, further improved by the use of a collagen matrix (AMIC). The addition of PRP and minced cartilage may biologically enhance the regeneration.

Dr. Matthias Steinwachs is Medical Director and knee specialist at SportClinic Zurich /Hirslanden, Clinic Zurich. He is a renowned international tissue regeneration specialist e.g. cartilage, meniscus etc. He is also member of the Swiss knee experts group (EGK) at the SGOT, former chairmen of the knee committee at the Society for Arthroscopy and Joint Surgery (AGA) and has a lectureship at ETH Zurich and University Freiburg.

History & physical exam

This is a 31 years-old physio therapist who suffered from a traumatic injury of the articular cartilage after a cycling accident. His goal is to regain range of motion as well as diminish pain, swelling and locking of joint. 


Magnetic resonance imaging (MRI) and diagnostic arthroscopy of the knee.


Treatment of the patient with the autologous matrix induced chondrogenesis (AMIC) technique using drilling of the subchondral plate on both sides of the defect. For the biological enhancement of the regeneration platelet rich plasma (PRP) and minced cartilage were added. 


Explanation of the postoperative phase and the results 3 months after the procedure.


Autologous Matrix-Induced Chondrogenesis

Publication: Systematic Review and Meta-Analysis of the Clinical Evidence on the Use of Autologous Matrix-Induced Chondrogenesis in the Knee

Enhanced Cartilage Repair Technique

Publication: Enhanced Cartilage Repair Technique with K-Wire Drilling Plus Subchondral Injected Plasma Rich in Growth Factors - A New Modified Microfracture Technique

Matrix-Associated Chondroplasty

Publication: Matrix-Associated Chondroplasty: A Novel Platelet-Rich Plasma and Concentrated Nucleated Bone Marrow CelleEnhanced Cartilage Restoration Technique