Imaging Study Of FAI About X-ray,CT And MRI

Purpose:To study manifold imaging factors,imaging signs and clinical characteristic of femoroacetabular impingement, for improving the clinical cognition to this syndrome ,and making a diagnose early and clear,and mamking a exact therapy.Materials and mathods: 1. Study object: 56 hips being elected out according to FAI imaging definition, Belonging to 54 people. 38 males, 16 females among them,2 male patients morbidity for pair of hips.age range 18～78 years, mean 36.2 years.All patients with complaints of the hip,groin or buttock pain,their duration was 6 months～30 years.To choose 50 volunteers who there are no the hip symptom carrying out contrast studies for observing the various imaging factors.2. Examination methods: The objects makes the examination,at least, two kinds in X-ray,CT and MRI.X-ray examine use DR imaging system,the routine pair of hips anteroposterior radiograph with the same method and condition.CT exmaine use Somatom Semsation 64 CT scanner with receive-only surface coil in axial scanning, coronal and oblique-axial reconstruction.MR examine use Symphony 1.5T superconducting MR scanner,MR imaging at the position of coronal and axial plane apply FSE-T₁WI,STIR-T₂WI and FSE-T₂WI-FS sequence,some patients apply FLASH-2D radial-sequence.3.Imaging factors and data analyse: The clinical analyse of FAI hips included: gender,age, disease course,hip ROM.The factors of X-ray,CT and MRI are measured, and the abnormal imaging findings are classified, the research includes measure methods for the proximal femur and acetabulum, observing abnormal morphology and density of hip, abnormal signal of bone and cartilage in the femoral head and acetabulum, variable factor between FAI group and control group, contrast study of two FAI types.4. Statistical analyses: Contrast study of FAI group and control group,and two FAI types, two-group t-test, paired t-test,Chi-square test in 2×2 table and Fisher's exact test are used in study,to make sure of value of factors by contrasting abnormal hip morphology and feature.Results: All FAI patients have carried out the short-term follow-up , exclude other the disease possibility. Abnormal imagings of nontraumatic hip demonstrate avascular necrosis in majority, inflammation, tuberculosis and traumatic osteoarthritis in minority. FAI is the category belonging to traumatic osteoarthritis, it is different from traumatic caused by acetabular dysplasia and injury, its theory basis and type, imaging findings shows obvious difference. 44 X-ray, 44 CT and 26 MR examinations were undertaken in 56 hips, 12 hips undertaken both X-ray and CT, 12 hips undertaken both MR and CT, and 2 hips undertaken X-ray,CT and MR. 1.Clinical data: hip ROM is the most accurate standard to judge hip motion, is one factor of hip motion function damages and degree.56 hips in FAI group and 50 hips in control group are contrasted in ROM, it shows singnificant difference in flexion and abduction, and no difference in adduction and extension. proliferations and sclerosis, 13 nonsmooth articular surfaces, 18 hips with abnormol subarticular bone density, 12 femoral heads with osteophyte or bony process.2. X-ray examination factors: 44 hips in FAI group and 50 hips in control group are contrasted in CE angle, Sharp angle, acetabular-head index and neck shaft angle. It shows four factors no significant difference in FAI and control groups (P>0.05)3. CT examination factors: 44 hips in FAI group and 20 hips in control group are contrasted inαangle,βangle, acetabular-head index and femoral head-neck ratio. Common coronal reconstruction was chosen from oblique-coronal reconstruction through 10 hips reexamination contract. It shows significant difference forαangle in FAI and control groups. CT imaging features are ananlysed, and show 26 acetabular4. MR examination factors: 26 hips in FAI group are analysed and summarized, it shows 13 femoral heads with abnormal signal, 14 acetabulums with abnormal signal, 13 hips with abnormal articular cartilage, 21 hips with joint effusion, 24 abnormal acetabular rims or labrums. MR detailed revelation to bone and cartilage can provide the definite evidence for developed characteristic appearance of FAI lesion, some FAI hips have features only in MRI.5. Both types contrast in FAI group: 44 X-ray hips ,44 CT hips, 26 MR hips are united into two groups according to abnormal femoral head or head-neck junction feature, one named cam group, another named pincer group. After contrast X-ray and CT, it shows significant difference for morphologic factors in CE angleαangle and neck shaft angle. After contrast imaging features of MR and CT, it shows significant difference in femoral heads with osteophyte or bony process, nonsmooth articular surfaces, acetabulums with abnormal signal and femoral heads with abnormal signal.Conclusion: This study have the summary and details in imaging part of FAI, and use part data to have verified the imaging haracteristics, on basis studying in abroad same kind study. Theαangle in oblique-axial reconstruction is mostly characteristic, there is obvious meaning for FAI diagnoses that the bony process of femoral head-neck junction, reduced femoral head-neck offset, coxa profunda and traumatic MR features of acetabular rims or labrums.