Introduction
Bone marrow aspirate concentrate (BMAC) is a source of stem cells as well as growth factors that is an appealing therapeutic for a variety of orthopaedic conditions due to its potential anti-inflammatory effects and healing properties. While the evidence surrounding the efficacy of BMAC injections in orthopaedics remains mixed, there has been little investigation into the safety of these injections in orthopaedic patients.
Objective
The aim of this systematic review was to investigate the complications of BMAC injections utilized in orthopaedic patients.
Methods
A systematic review was performed by searching the PubMed database to locate randomized controlled trials utilizing BMAC injections with any mention of complications compared to another injectable. Studies that included an operative intervention or combined BMAC with other modalities were excluded. The search strategy used was: “((bone marrow) AND (aspirate OR “concentrate”)) OR (BMAC) AND (Orthopaedic OR orthopedic)).” Data on sample size, patient characteristics, complications, and site of BMAC injection were extracted from the articles. Additionally, the quality of studies were assessed using the Consolidated Standards of Reporting Trials (CONSORT) criteria for the randomized controlled trials.
Results
A total of 7 randomized controlled trials were identified. Knee osteoarthritis was the most commonly studied condition, with 6 studies identified, the remaining study investigated BMAC in glenohumeral osteoarthritis. A total of 494 patients were included, 274 of whom received BMAC injections. The mean follow-up time was 13 months. 3 studies compared BMAC to hyaluronic acid, 1 to PRP, 1 to PRP and BMAC, and 1 to saline. Overall the BMAC group had a complication rate of 39.56% while the comparison group had a complication rate of 27.27% (p = 0.576). The number needed to harm was 44. The most commonly reported complication was effusion (51.85%) followed by knee pain (29.63%). The comparison groups of the included studies had similar complications to the BMAC group with effusion and knee pain being the most common. There were no reported infections in either group.
Conclusion
BMAC injections are safe with few complications, many of which are minor. Most of the reported complications are self-limiting and did not have any long term deleterious effects on patients.