Traditionally,anterior cruciate ligament (ACL)injuries have been treated with surgical reconstruction.
This means, that the torn ligament is replaced with newACL graft tissue.
Performing ACL repair surgery has been done for several decades, but it has never worked very well.
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Results were always much worse when compared with ACL reconstruction.
ACL Repair
ACL repair surgery has never worked very well.
Studies have found that these people often needed additional surgical procedures.
In general, ligaments will heal without surgical intervention.
For example, when someonetears the medial collateral ligament(MCL), they seldom require a surgical procedure.
Similarly,ankle sprain injuries(torn ligaments in the ankle) seldom require surgical repair.
Most often, these ligaments will heal without surgical intervention.
So why is it the case that the anterior cruciate ligament in the knee does not heal?
The area surrounding the ACL is different.
The other ligaments mentioned before are surrounded by soft tissues such as muscles and tendons.
The anterior cruciate ligament sits right in the center of the knee joint.
Surrounding the ligament is joint fluid, called synovial fluid.
Instead of this being an environment that supports healing, the synovial fluid actually inhibits a healing response.
When these types of early ACL repairs were performed, the results were very poor.
ACL Reconstruction
In the case ofACL tears, the gold standard for treatment is ACL reconstruction.
Reconstruction means that the old ACL is removed, and a new ligament is created using non-ACL tissue.
ACL reconstructive surgeryis often successful, but it does not come without downsides.
One of the major problems of ACL reconstruction surgery is obtaining the tissue used to reconstruct the ligament.
Donor grafts can be beneficial in the lower demand athletes such as weekend warriors.
Arthritis is a likely complication in the absence of reconstruction and, overall, surgery reduces this risk.
However, this is the latest development and has shown someearly resultsthat have been promising.
Surgeons then implant a synthetic matrix around the ends of the torn ACL.
Within this matrix, stem cells are injected to make it stimulate the healing process.
It is not known if this procedure is better or worse than ACL reconstruction.
There have been some promising early results for bridge-enhanced ACL repair surgery.
A Word From Verywell
Injuries of the anterior cruciate ligament are potentially devastating injuries for young athletes.
Research is ongoing to develop a better way to address ACL injuries.
One of the techniques proposed to better manage ACL injuries is repair of the ligament.
The gold standard for treatment of ACL injuries is still reconstructive surgery.
Current status and potential of primary ACL repair.
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The Bridge-Enhanced Anterior Cruciate Ligament Repair (BEAR) Procedure: An Early Feasibility Cohort Study.Orthop J Sports Med.
Bench-to-bedside: Bridge-enhanced anterior cruciate ligament repair.J Orthop Res.
2017 Dec;35(12):2606-2612. doi:10.1002/jor.23632
