The study, “Changes in Cross-sectional Area and Signal Intensity of Healing Anterior Cruciate Ligaments and Grafts in the First 2 Years After Surgery,” compared 10 patients treated with the BEAR implant to 10 treated with traditional hamstring autografts, using the contralateral ACL as reference. The study showed ACLs treated with the BEAR implant had a cross-sectional area (quantity), signal intensity (quality), and sagittal orientation that were similar to the contralateral ACL at 12 months, whereas hamstring autografts were significantly larger and more vertically oriented than the native ACL at 24 months.
“The results highlight the ability of the BEAR implant to restore the signal intensity and anatomy of the torn ACL to those of the native ACL,” said Martha Murray, M.D., professor of orthopedic surgery at Harvard Medical School, an orthopedic surgeon in the Sports Medicine Division at Boston Children’s Hospital and founder of Miach Orthopaedics. “MRIs from these two cohorts were helpful in comparing the changes over a two-year period, as well as the influences of other anatomic features of the knee after surgery. While more study is needed, these results show promise for the regenerative properties of the BEAR implant in restoring more normal knee anatomy.”
Specific study results include:
- Mean cross-sectional area of the hamstring autografts was 48% to 98% larger than the contralateral intact ACLs at all time points, whereas BEAR ACLs were 23% to 28% greater at 3 and 6 months but similar at 12 and 24 months.
- BEAR ACLs were similar in sagittal orientation to the contralateral ACLs, while the hamstring autografts were 6.5% more vertical.
“We are encouraged by the results of this study, which add to the growing body of evidence supporting use of the BEAR implant as a potential treatment option for people with torn ACLs,” said Martha Shadan, president and CEO, Miach Orthopaedics. “ACL repair using the BEAR implant is a new approach to an old problem that we think has the potential to improve outcomes for people with torn ACLs.”