Effect of joint position and ligament tension on the MR signal intensity of the cruciate ligaments of the knee.
Six cadaveric lower extremities were imaged with T1-weighted spin-echo pulse sequences with the knees extended and flexed to 90 degrees. Magnetic resonance signal intensities of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were compared. Changing from extension to flexion resulted in decreased signal intensity in six of six ACLs and five of six PCLs. Two of the knees were then imaged with and without tension applied to the ACL. Both specimens showed a decrease in signal intensity with tension, followed by an increase in signal intensity with release of the tension. Finally, in three of the limbs the ACL was surgically reconstructed and then imaged with and without tension applied to the tendon graft. Signal intensity decreased with tension and increased with release of the tension in all three specimens. Thus, joint position and changes in ligament tension affect the signal intensity of the ACL and PCL, generally resulting in a signal intensity decrease with tension.
Smith
K L
KL
Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, East Lansing 48824-1314.
Daniels
J L
JL
Arnoczky
S P
SP
Dodds
J A
JA
Cooper
T G
TG
Gottschalk
A
A
Shaw
D A
DA
D000368:Aged; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology / Q000502:physiology* / Q000601:surgery; D006801:Humans; D007089:Image Enhancement; D007719:Knee Joint / Q000033:anatomy & histology* / Q000502:physiology; D008279:Magnetic Resonance Imaging; D017847:Patellar Ligament / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery; D016119:Posterior Cruciate Ligament / Q000033:anatomy & histology / Q000502:physiology* / Q000601:surgery; D016059:Range of Motion, Articular / Q000502:physiology; D013314:Stress, Mechanical