Introduction
So, you have a cartilage injury in your joint, probably your knee or ankle. This was probably diagnosed by an orthopaedic surgeon and likely confirmed by MRI scans. One of the treatment options that would be offered to you might be a microfracture of the cartilage injury, where the surgeon informs you that he will be performing an arthroscopic surgery procedure, whereby tiny fractures are created in the bone beneath the damaged cartilage, allowing blood and stem-cell–rich marrow to seed the defect and ‘repair’ cartilage. It might sound ideal; however, reality is more complicated.
How Microfracture Surgery Actually Works
Before weighing pros and cons, here is how microfracture surgery is performed and why opinions have shifted: small holes are created in the subchondral bone to encourage a marrow clot, a technique popularised in the early 2000s by Steadman et al and supported by significant literature1. However, rehabilitation is demanding with extended non-weight-bearing (i.e. you are not supposed to put weight on the affected joint) and a slow return to sport/exercise of around nine months! More importantly, with more advanced research being performed, orthopaedic surgeons have begun to realise that there’s actually more harm than good when a microfracture surgery (Figure 1) is being performed.2
Microfracture Surgery Complications to Consider
In practice, when microfracture surgery is being performed on its own, specific problems often show up:
Destruction of the Subchondral Bone Anatomy2
When a microfracture surgery is being performed, the subchondral bone that supports the cartilage is damaged and injured, and instead of healing, it starts to form subchondral cysts, or liquid filled sacs in the bone, that increases in size and destroys the bone (for more understanding of cartilage injuries, please refer to my article: “Why does cartilage not heal by itself easily: Understanding cartilage injuries 101”). No cartilage forms, and instead the bone cannot support your joint when loading and you suffer from constant pain.
Poor Cartilage Formation2
When cartilage does grow after microfracture surgery for a cartilage injury (e.g knee or ankle), it’s typically lower-quality fibrocartilage that does not tolerate everyday joint stresses well. This scar-type tissue is softer and rougher than normal hyaline cartilage, so it tends to wear down over time and pain symptoms can return within a few years.
Intra-articular Osteophytes (Bone Spurs)3
Occasionally, the microfracture channels ossify (turn into bone) rather than fill with cartilage, producing osteophytes at the defect margin (the edge of the injury). These bony projections can rub or scrape against the opposing articular surface during motion, accelerating cartilage wear, irritating the synovium (the joint lining), and causing catching (a brief snagging or “stuck” sensation) with recurrent pain.
“Burns the Bridge” for Future Procedures4,5
With subchondral bone damage after microfracture surgery, long-term research has shown that salvage procedures such as scaffold-based repair or cartilage transplantation have poorer outcomes4,5 at previously microfractured sites. Essentially, should microfracture surgery fails, the likelihood of success with subsequent cartilage repair procedures is poorer, effectively burning the bridge to better long-term injury treatment options.
Moving Beyond Microfracture Surgery6,7
All things considered, many orthopaedic surgeons specialising in cartilage repair, like myself (Dr Francis Wong Keng Lin, FRCSEd (Orth), PhD), have largely abandoned the use of microfracture surgery. Generally, the best approach would be meticulous debridement (careful removal of damaged tissue) of the defect.
Building on that approach, the next step is to prepare a healthy repair bed and then support the defect appropriately. The subchondral bone is readied to a healthy, bleeding base without drilling holes (Figure 2). The repair is then supported with an acellular scaffold augmented with Bone Marrow Aspirate Concentrate (BMAC), which as its name implies is concentrated bone marrow blood taken from your bone marrow6 (Figure 3). When suitable, small pieces of your own cartilage (minced cartilage) are added to further enhance healing7. Detailed techniques published by myself can be found on our website.
Microfracture Surgery: Key Takeaways
Taken together, the earlier points explain why microfracture surgery is no longer a preferred option among orthopaedic surgeons. In particular, its tendency to form inferior fibrocartilage, disrupt subchondral bone, and promote intra-articular osteophytes leaves patients with a poorer outlook for future cartilage repair treatments.
Accordingly, contemporary repair focuses on building a durable foundation and conserving bone. In practice, that means meticulous debridement, preparation of a healthy subchondral base, and scaffold support, often augmented with BMAC and/or minced cartilage.
The practical takeaway is straightforward: outcomes improve when technique, implants, and judgement align. Choosing an experienced orthopaedic surgeon who stays current with evolving methods for cartilage repair is the single most controllable factor in achieving durable results.
Speak to Oxford Cartilage & Sports Centre (Oxford Orthopaedics)
“Sounds scary, doesn’t it? A microfracture.” To a layperson, the idea of a surgery that creates tiny holes in bone to “grow” or “repair” cartilage can feel intimidating, so it is reasonable to seek clarity before deciding. A focused second opinion with Dr Francis Wong can review MRI findings, location of injury, defect size, and the condition of the subchondral bone, then discuss cartilage-preserving treatment options that align with activity goals and recovery timelines. To speak with Oxford Cartilage & Sports Centre by Oxford Orthopaedics, please contact the clinic to book an appointment.
References
- Steadman JR, Rodkey WG, Rodrigo JJ. Microfracture: surgical technique and rehabilitation to treat chondral defects. Clin Orthop Relat Res. 2001 Oct;(391 Suppl):S362-9. doi: 10.1097/00003086-200110001-00033. PMID: 11603719.
- Bert JM. Abandoning microfracture of the knee: has the time come? Arthroscopy. 2015 Mar;31(3):501-5. doi: 10.1016/j.arthro.2014.12.018. PMID: 25744322.
- Demange MK, Minas T, von Keudell A, Sodha S, Bryant T, Gomoll AH. Intralesional Osteophyte Regrowth Following Autologous Chondrocyte Implantation after Previous Treatment with Marrow Stimulation Technique. CARTILAGE. 2017;8(2):131-138. doi:10.1177/1947603516653208
- Merkely G, Ogura T, Bryant T, Minas T. Severe Bone Marrow Edema Among Patients Who Underwent Prior Marrow Stimulation Technique Is a Significant Predictor of Graft Failure After Autologous Chondrocyte Implantation. Am J Sports Med. 2019 Jul;47(8):1874-1884. doi: 10.1177/0363546519853584. PMID: 31251661.
- Cogan CJ, Friedman J, You J, Zhang AL, Feeley BT, Ma CB, Lansdown DA. Prior Bone Marrow Stimulation Surgery Influences Outcomes After Cell-Based Cartilage Restoration: A Systematic Review and Meta-analysis. Orthop J Sports Med. 2021 Sep 24;9(9):23259671211035384. doi: 10.1177/23259671211035384. PMID: 35146031; PMCID: PMC8822078.
- Ow ZGW, Ting KJE, Wong KL. Single-Stage Arthroscopic Cartilage Repair With Chondrectomy and Implantation of a Templated Membrane Collagen Scaffold With Bone Marrow Aspirate Concentrate Augmentation (AMIC Plus). Arthrosc Tech. 2023 Oct 30;12(11):e2085-e2091. doi: 10.1016/j.eats.2023.07.030. PMID: 38094947; PMCID: PMC10714417.
- Zhang EJX, Ow ZGW, Lie EV, Dhanaraj ID, Wong KL. Arthroscopic Cartilage Repair of the Patella With Minced Cartilage and Collagen Membrane Scaffold With Bone Marrow Aspirate Concentrate. Arthrosc Tech. 2024 Nov 13;14(4):103308. doi: 10.1016/j.eats.2024.103308. PMID: 40453020; PMCID: PMC12126052.
