In this article
Adding BMAC to a partial meniscectomy did not improve the primary one-year outcome for patients with mild arthritis in a 2024 randomized trial from Dr. Cole’s group. That result applies to a specific procedure and patient group, not to every knee or every biologic use. Every knee is different, and so is the reasoning behind each recommendation.
Patients weighing an arthroscopic meniscectomy are often asked whether adding a biologic injection such as bone marrow aspirate concentrate (BMAC) might help their recovery. The honest answer depends on the patient, the tear, the condition of the knee, and what the research shows for that specific situation. A 2024 randomized trial offers a useful example of why these decisions are individualized rather than one-size-fits-all.
Why Biologics Like BMAC Come Up With Meniscus Surgery
BMAC is concentrated from a patient’s own bone marrow and has a recognized safety profile. It has been used alongside arthroscopic partial meniscectomy because of its theoretical potential to support cartilage health, particularly in knees with mild osteoarthritis. According to the trial’s authors, injecting BMAC during meniscectomy in patients with a meniscal tear and mild arthritis had not previously been tested in a randomized controlled trial. That gap is why a controlled study was needed. How BMAC differs from platelet-rich plasma (PRP) is covered in Orthobiologics Explained: PRP vs. BMAC.
What the 2024 Trial Tested
The trial was published in The American Journal of Sports Medicine by a team at Rush University Medical Center, with Dr. Adam Yanke as first author and Dr. Cole as senior author. It enrolled adults with a symptomatic meniscal tear and mild knee osteoarthritis who were candidates for arthroscopic partial meniscectomy. Patients were randomized to receive either a BMAC injection during surgery or surgery without BMAC, and neither patients nor evaluators knew which group a patient was in. Of 95 patients enrolled, 83 were included in the final analysis, and the groups were similar at baseline in patient characteristics, surgical variables, and pre-surgery scores.
The primary measure was the International Knee Documentation Committee (IKDC) score at one year, a widely used assessment of knee function and symptoms. Secondary measures tracked other patient-reported outcomes through two years, along with X-ray grading of arthritis at one year.
What the Trial Found
At one year, adding BMAC did not produce significant differences in IKDC scores or X-ray outcomes. Both groups improved, and the authors concluded that meniscectomy may benefit patients with meniscal tears and mild arthritis with or without BMAC. Some secondary measures favored the BMAC group: a higher share of those patients reached a clinically meaningful improvement on the KOOS Symptoms and Sport scores at one year. The primary outcome, however, did not differ.
In plain terms, the trial answers a specific question: on average, in this type of patient, does BMAC change the one-year result? It does not say that BMAC has no role for any patient or any procedure.
Why One Trial Does Not Answer Every Patient’s Question
Biologic effectiveness tends to depend on the exact tissue, procedure, and condition being treated. Results from one setting do not automatically transfer to another. In a separate randomized trial in rotator cuff repair, for example, patients who received BMAC had significantly fewer high-grade tissue abnormalities on MRI one year after repair. Trials also report group averages, while individual patients differ in age, arthritis severity, tear pattern, activity goals, and prior treatment. The authors themselves noted open questions, including long-term arthritis progression and whether a different adjuvant, delivery method, or patient subgroup might respond differently.
How Surgeons Decide Whether to Recommend a Biologic
Deciding whether to add a biologic is a judgment call that weighs several factors together: the condition of the cartilage, the stage of arthritis, the type of tear, and what the patient hopes to return to doing. In some patients, those factors support adding a biologic. In others, surgery alone is the better plan. The goal is a recommendation matched to the individual knee, supported by the best available evidence, and explained clearly enough to allow an informed choice. Because the diagnosis shapes the plan, the distinction explained in Cartilage Damage vs. Arthritis matters here too. When arthritis is part of the picture, the same principles guide knee cartilage care more broadly.
Questions to Ask Your Surgeon
If a biologic is suggested, or not suggested, alongside your surgery, these questions can guide the conversation:
- Why do you recommend, or not recommend, BMAC for my knee?
- What results can I realistically expect with and without it?
- What does the research show for patients like me?
- What extra time, cost, and recovery does it involve?
An evaluation with a sports medicine specialist can explain the options for your situation, and requesting an appointment online is a good place to start.
Frequently Asked Questions
Does BMAC improve results after meniscectomy?
In a 2024 randomized trial of patients with a meniscal tear and mild arthritis, adding BMAC did not change the primary one-year outcome, although some secondary measures favored the BMAC group.
Does that mean BMAC doesn’t work?
No. Results depend on the procedure and tissue. In rotator cuff repair, for example, a separate trial found better tendon healing on MRI with BMAC.
Is BMAC covered by insurance?
Usually not. Most carriers classify it as investigational and consider it an uncovered benefit, so patients pay out of pocket.
Who decides whether BMAC is right for me?
You and your surgeon, based on your cartilage condition, arthritis stage, tear type, activity goals, and the evidence for your situation.
Medical Disclaimer: This information is for educational purposes only and does not constitute medical advice. For diagnosis and treatment recommendations, please consult with Dr. Cole or another qualified orthopedic specialist at Midwest Orthopaedics at Rush.
Resources
Yanke AB et al. 2024. A prospective, randomized, double-blind clinical trial to investigate the efficacy of autologous bone marrow aspirate concentrate during arthroscopic meniscectomy in patients with early knee osteoarthritis. The American Journal of Sports Medicine. https://doi.org/10.1177/03635465241275647
Cole BJ et al. 2023. Prospective randomized trial of biologic augmentation with bone marrow aspirate concentrate in patients undergoing arthroscopic rotator cuff repair. The American Journal of Sports Medicine. https://doi.org/10.1177/03635465231154601
