New quantitative method to measure the Hill-Sachs lesion: validation of Hardy's radiographic method for MRI/AMRI()

OBJECTIVE: To validate Hardy's radiographic method for magnetic resonance imaging/magnetic resonance arthrography (MRI/MRA) in the assessment of Hill-Sachs lesion (HSL) involvement in patients with a history of anterior shoulder instability. METHODS: This study retrospectively evaluated 53 shoulder radiographs and MRI/MRA to compare the measurements of HSL through Hardy's radiographic method. Imaging exams used in the study were conducted between the March 2013 AND September 2015. The data obtained from these exams were carried out during 2015. Inclusion criteria were previous history of anterior instability of the shoulder, presence of LHS, and radiographs at 70° medial rotation. RESULTS: MRI/MRA had a sensitivity of 100% and specificity of 100% when using the Hardy's radiographic method 20% cutoff point to measure the HSL. CONCLUSION: MRI/MRA can be used to assess the degree of HSL involvement with the same reliability as Hardy's radiographic method.