Knee microfracture has become a standard of care procedure for small knee arthritis cartilage lesions. However, do we have research showing that it helps long-term? What are knee microfracture results? A new research study suggests that the long-term outcomes are pretty bad.
Knee microfracture is about a 20 year old orthopedic surgery technique that’s commonly used during knee arthroscopy to treat small holes in the cartilage. The surgeon literally pokes holes in the knee bone of the cartilage hole trying to prompt bleeding of the bone marrow into the area. The concept is that the cartilage will heal, if not with normal cartilage then a scarred type of cartilage called fibrocartilage. The procedure has become so commonplace that many of my patients tell me that when they awoke from their routine knee arthroscopy was the first time they were informed that the procedure had been done based on the surgeon finding a hole in the cartilage. Since the downtime after micro fracture is significantly more intense, most patients are not happy to find out that the surgery was performed.
Does microfracture surgery work? You might be surprised to learn that we still don’t know via high level research that microfracture is more effective than doing nothing. In addition, we know even less about the long-term effects of the surgery. This is why a recent study is important. The researchers looked at 110 patients who had knee microfracture surgery and followed them for an average of 12 years after the procedure. Over 1/3 of the patients needed additional knee surgeries and almost half had a poor outcome from microfracture. Perhaps the author’s own conclusion sums up best what they found: “a normal knee function was generally not achieved, and many patients had further surgery. The results call for more research and, at present, caution in recommending microfracture in articular cartilage defects, especially in subgroups with worse prognosis.” Who had a worse prognosis? Anyone with any type of arthritis or meniscus tear.
The upshot? The long-term knee microfracture results aren’t good. In addition, the added invasiveness of the surgery (poking many holes in the bone) and added downtime (many weeks on crutches), don’t seem to be be matched by good enough long-term results for the authors of this paper to recommend the surgery in most patients.