MRI manifestations of anatomy and injuries of thumb extensor and flexor mechanism / 中华全科医师杂志

ABSTRACT

Objective:To explore the anatomy and injuries features of the thumb extensor and flexor mechanism with MRI.Methods:Ten healthy subjects without thumb injury and 20 patients with thumb extensor or flexor mechanism injuries were recruited in the study between September 2013 and September 2021. All subjects underwent MRI examination, the MRI features of thumb extensor or flexor mechanism in healthy subjects and patients were analyzed. The imaging findings were compared with the surgical results and confirmed by followed up in patients.Results:The healthy subjects showed homogeneous low-signal-intensity on T1-weighted and proton-fat saturation sequence(PD FS) images. Twenty patients with thumb extensor or flexor mechanism injures(including 8 cases of extensor pollicislongusinjury,1 case of extensor pollicisbrevis injury, 4 cases of flexor pollicislongus injury, 2 cases offlexor pollicis brevis injury and 5casesofpulley injury) demonstrated poor definition in T1WI, and heterogeneously increased signal intensity in PD-FS. Depending on the degree of injury, the fibers may be partially or completely discontinuity of the involved tendons. There was edema in the soft tissues surrounding the injured sites.Conclusion:MRI is an accurate method for evaluation of the anatomy and pathological conditions of the thumb extensor and flexor mechanism.