About AMIC Procedure

Larger cartilage defects which are not suitable for an OATS procedure may be suitable for an AMIC (Autologous Matrix-Induced Chondrogenesis) procedure, which involves a microfracture and application of a collagen membrane to fill the defect. This procedure is suitable in cases where the defect is larger than 2.5cm2, as these cases are not suitable for other types of cartilage surgery.


Following surgery you are likely to be in a brace, with limited movement and only taking a small amount of weight through the knee for the first six weeks. For the first two weeks range of motion is likely to be 0-60°, with 0-90° for the next two weeks then 0-120° until 6 weeks. Following patellofemoral AMIC, your movements will be restricted in a brace from 0-30° for two weeks, then 0-60° for two weeks, then 0-90° for the final two weeks. Generally, you should be back to using the exercise bike from 8 weeks, with light jogging at the 6 month mark and should not return to contact sports until 12 months following surgery.


Outcome of AMIC Procedure

Although results in the femur and tibia are good, the historical results in the patellofemoral joint are less predictable. However more recent studies do suggest that good outcomes are achievable. 75% of patients report that their knee function is “good” or “excellent” following AMIC. Follow-up MRI studies have also shown good quality cartilage restoration.

I invite all my patients to submit their knee scores. This helps me to monitor your ongoing recovery, but also assists with research purposes in the future. Please rest assured that any personally identifiable information will not be shared with anyone else, and that all information used for research will be anonymised.