Table 1.

Objective criteria used to evaluate and compare MARS MRI and CT for the assessment of MOM hips

Soft tissue lesion
Soft tissue lesion present or absent?	Yes/No
Imperial classification?	1/2a/2b/3
Location(s) in relation to joint?	Anterior/Posterior/Medial/Lateral
Size (mm)?	Anterioposterior x Mediolateral x Craniocaudal
Musculotendinous pathology
Hip muscle atrophy?	Grade 0/1/2/3
• Glutei (gluteus maximus, medius, and minimus)
• Short external rotators (piriformis, obturator internus, obturator externus)
• Iliopsoas
• Quadratus femoris
Bony pathology
Osteolysis?	Yes/No
If yes, femoral/acetabular/both?