
Jay P. Shah, MD
DALLAS – November 09, 2022 – Magnetic resonance imaging (MRI) can reliably establish measurements of anterior cruciate ligament (ACL) “fingerprints” that are critical to graft placement for reconstructive surgery, report researchers from UT Southwestern.
Jay P. Shah, MDassistant professor at Department of Orthopedic Surgery at UTSW, and his colleagues used two- and three-dimensional magnetic resonance imaging (MRI) to determine these measurements, an approach that had not been explored before. Their study was published in European radiology.
“This study proves that 2D and 3D MRI is reliable in determining the specifics of the ACL impression,” said Dr. Shah.
The ACL is a crucial stabilizing ligament of the knee, and a torn ACL is one of the most common ligament injuries with serious consequences in terms of morbidity, mobility and cost. Among athletes who sustain ACL tears, 37% are unable to return to pre-injury levels.
For younger patients, ACL tears are often repaired with reconstructive surgery. For successful reconstruction, tunnels must be created in the tibia and femur. The ACL impression is used to determine where these tunnels should be drilled for graft placement.

A magnetic resonance image (MRI) of the knee illustrates how the location of the anterior cruciate ligament (ACL) baseplate is determined, with measurements relative to nearby anatomical landmarks.
The anatomical placement of ACL grafts impacts postoperative stability and potentially the future risk of arthritis for patients. Improper placement of the tibial tunnels can lead to reduced rotational stability of the knee. Accurate measurements of ACL impressions will allow surgeons to reliably predict anatomy and plan surgery.
To determine where to make the tunnels, surgeons typically use arthroscopy, in which a camera connected to a tube is inserted through a small incision to view the joint. However, the locations of ACL indentations are not always clear under arthroscopy.
MRI has been used successfully to observe the structure of the ACL. Dr. Shah and a team of researchers reviewed 2D and 3D knee MRIs of 101 adult patients to measure the tibial-ACL and intermeniscal ligament-ACL margins. They then compared the measurements to those obtained under arthroscopy.
“We found that the mean differences between 2D and 3D measurements of the tibia-ACL and intermeniscal ligament-ACL are small, and 2D and 3D MRI can be reliably used to delineate foot plate anatomy. of the ACL,” said Dr Shah.
Establishing ACL impression measurements using MRI can help reduce surgery times, reduce recovery times and improve patient outcomes, Dr. Shah added. Future studies will evaluate the results of ACL reconstruction based on different impression measurements.
Other UTSW researchers involved in this study were Toan Nguyen, Shamrez Haider, David Tietze, Yin Xi, Uma Thakur and Avneesh Chhabra.
About UT Southwestern Medical Center
UT Southwestern, one of the nation’s leading academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty has received six Nobel Prizes and includes 24 members of the National Academy of Sciences, 18 members of the National Academy of Medicine, and 14 researchers from the Howard Hughes Medical Institute. Full-time faculty of more than 2,900 are responsible for groundbreaking medical advances and committed to rapidly translating scientific research into new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 100,000 inpatients, more than 360,000 emergency room cases, and oversee nearly 4 million outpatient visits annually.