Study On Imaging Performance And Clinical Application Of Femoroacetabular Impingement Syndrome

【Purpose】Femoroacetabular impingement has been recognized as an underlying cause of hip pain and secondary osteoarthritis.Several surgical options are available for treatment, and are guided by the severity and location of the disease,as well as the expertise and technical preferences of the surgeon.Accurate diagnosis of the impingement disease pattern and precise surgical technique are the basis of successful surgical care.On basis studying in abroad same kind of study,the purpose of our study is to probe the standard of early diagnosis of FAI,and the imageology appearance of radiography,spiral CT scanning and three-dimensional reconstruction,and MRI of progression of FAI patients.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 making a exact therapy.【Materials and mathods】1.Clinical informationFrom January 2007 to January 2009,75 hips being elected out according to FAI imaging definition,44 males,31 females among them,11 patients morbidity for pair of hips,randomly selected either side hip joint to study.age range 18～69 years,mean 37.5 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,age range 20～45 years,mean 31.9 years.26 males,24 females among them2.Examination methodsThe objects makes the examination,75 in X-ray,39 in CT and 17 in MRI.X-ray examine use DR imaging system,the routine pair of hips anteroposterior radiograph with the same method and condition.CT exmaine use GE Light speed 16 CT scanner with receive-only surface coil in axial scanning,coronal and oblique-axial reconstruction.MR examine use GE Signa VH/i 3.0T superconducting MRI scanner,MRI imaging at the position of coronal and axial plane apply FSE-T1WI,STIR-T2WI and FSE-T2WI-FS sequence.3.Imaging factors and data analyseThe clinical analyse of FAI hips included gender and age.The factors of X-ray,CT and MRI are measured and compared between FAI group and control group,the abnormal imaging findings of X-ray,CT and MRI are classified cohort studied.4.Imaging analyses methodsAll images were saved and sended to PACS.Three radiologists measured all the data of X-ray and CT image on PACS,and computed the average.2 radiologists examined the abnormal imaging findings,the final resul were acquired by the 2 radiologists.5.Statistics analysisStatistics analysis was performed with SPSS13.0 software.Contrast study of FAI group and control group,and three FAI types.Chi-square test in 2×2 table,Chi-square test in R×C table,One-way ANOVE,Binary logistic regression and Independent sanples t-test are used in study.Probability values＜0.05 were considered statietically signficant.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 disease possibility,such as abnormal imagings of nontraumatic hip demonstrate avascular necrosis,ankylosing spondylitis,inflammation,tuberculosis and traumatic osteoarthritis 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.1.X-ray examination factors:75 hips in FAI group and 50 hipsin control group are contrasted in Sharp angle, center-edge angle CCD angle,acetabular-head index,acetebular deph-to-width index, HTE angle and femoral head-neck offset.One-way ANOVE was used in the contrast study of these 7 factors of the FAI group and the control group.It shows four factors significant difference in FAI and control groups(P＜0.05).They are Sharp angle,HTE angle,acetebular deph-to-width index and femoral head-neck offset.Binary logistic regression and Independent Sample T-test was used in contrast study of three FAI types and the control group.75 hips are united into three groups according to abnormal femoral head or head-neck junction feature,named cam group,pincer group and mixed group.It shows five factors significant difference in FAI and control groups(P＜0.05).They are CE angle,Sharp angle,HTE angle,acetebular deph-to-width index and femoral head-neck offset.X-ray imaging features are ananlysed,and show 21 femoral heads with osteophyte or abnormal bony apophysis(the positive rate is 28.00%),27 reduced femoral head-neck offset(the positive rate is 36.00%),22 acetabular hypsokinesis(the positive rate is 29.33%),and 24 acetabular proliferations and sclerosis(the positive rate is 29.33%).Chi-square test in R×C table was uesd in the contrast study of these X-ray imaging features between three FAI types.It shows three festures significant difference.They are osteophyte or bony process,reduced femoral head-neck offse,acetabular hypsokinesis.2.CT examination factors:39 hips in FAI group and 20 hips in control group are contrasted in a angle.Independent Samples Test shows significant difference forαangle in FAI and control groups(P＜0.05).One-way ANOVE was used in the contrast study of three FAI types and the control group.There was statistical signficance inαangle between the C group and the P group.CT imaging features are ananlysed,and show 16 femoral heads with osteophyte or bony process(the positive rate is 41.02%),14 nonsmooth articular surfaces(the positive rate is 35.90%),15 acetabular proliferations and sclerosis(the positive rate is 38.46%)and 4 herniation pits(the positive rate is 10.26%). Chi-square test in R×C table was uesd in the contrast study of these CT imaging features between three FAI types.It shows osteophyte or bony process significant difference only.3.MR examination factors:17 hips in FAI group are analysedand summarized,it shows 15 hips with joint effusion(the positive rate is 88.24%),10 abnormal acetabular rims or labrums(the positive rate is 58.82%),7 femoral heads with abnormalsignal(the positive rate is 41.18%),8 acetabulums with abnormal signal(the positive rate is 47.06%),and 8 hips withabnormal articular cartilage(the positive rate is 47.06%).MRI detailed revelation to bone and cartilage can provide the definite evidence fordeveloped characteristic appearance of FAI lesion,some FAI hips have features only in MRI.4.Clinical examination factors:In 75 patients of FAI group,44 were men,31 were women.In 50 patients of control,26 were men,24 were women.Chi-square test in 2×2 table was uesd in the contrast study of sex between the FAI group and the control group.It shows that there wasn't statistcal significance(P＞0.05) in the differerca betwwen the FAI group and the control group.Chi-square test in R×C table was uesd in the contrast study of sex between the three FAI types.It shows that there wasn't statistcal significance (P＞0.05) in the differerca betwwen the three FAI types.The freauencies histogram and normal curve of the FAI group patients' age shows the age was centered largely in the 25～45,73.33%of the total.[Conclusion]To date,imaging features of this condition have not been widely discussed in the radiolo gic literature.The radiographic findings of FAI are not widely discussed and recognized by physicians.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.there is obvious meaning for FAI diagnoses that osteop hyte or abnormal bony apophysis,reduced femoral head-neck offset,acetabular hypsokinesis,and acetabular proliferations and sclerosis in the X-ray imaging.C T scan examination and reconstruction of multi-directional display can be bette r to show the FAI characters.Theαangle in oblique-axial reconstruction is m ostly characteristic.Magnetic resonance(MR) imaging and can be associated w ith progressive damage to the adjacent cartilage,and has a higher detection sens itivity and specificity of the acetabular labrum and cartilage injury.MRI featur es of acetabular rims or labrums.The diagnosis of femoroacetabular impingeme nt(FAI) is based on the patient's clinical history and physical examination and is further supported by findings at radiography,computed tomography,and MR imaging.