By Jordana Bieze Foster
Altered tibial position during flexion and extension one year after anterior cruciate ligament (ACL) reconstruction is associated with early cartilage changes, according to research presented in late March in Las Vegas at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS).
Investigators from the University of California San Francisco (UCSF) performed two types of magnetic resonance imaging (MRI) on 25 patients (13 women) prior to ACL reconstruction and at six months and one year after surgery. Kinematic MRI was used to assess the joint anatomy in both knees during flexion and extension while the partcipant was loaded with 25% body weight; T1ρ imaging was used to detect early cartilage changes (higher T1ρ relaxation values are associated with decreased proteoglycan content).
Between-limb differences in tibial position during flexion and extension were significantly associated with degenerative changes in the reconstructed limb at one year.
“This relationship may provide insight into the implications for development of knee osteoarthritis after ACL reconstruction,” said Musa Zaid, a medical student at UCSF, who presented the findings at the AAOS meeting.
Zaid M, Lansdown D, Su F, et al. Abnormal kinematics in the ACL reconstructed as a mechanism of early onset osteoarthritis. Presented at the American Academy of Orthopaedic Surgeons annual meeting, Las Vegas, NV, March 2015.