Magnetic resonance imaging and spectroscopy of thigh muscles in cruciate ligament insufficiency

Abstract

In 21 patients with injury-related, chronic, anterior cruciate ligament insufficiency, 1H-magnetic resonance (MR) imaging and 31P-MR spectroscopy of the quadriceps muscles were performed with a systemic superconductive MR apparatus. The quadriceps of the noninjured side was used as the control. The quadriceps had a reduced cross-sectional area, but the knee flexors were not reduced. T2 values were prolonged in the vastus lateralis, medialis, and intermedius, but those of the rectus femoris were not. Phosphocreatine per inorganic phosphate measured with 31P-MR spectroscopy was decreased in the atrophied muscles, which correlated with the muscular cross-section. There was no difference in the muscular pH as recorded by the chemical-shift measurements of phosphocreatine and inorganic phosphate. Serial measurements of muscle cross-sectional area and high-energy phosphate bonds reflect the recovery of muscles.