Hip Joint Magnetic Resonance Imaging Research Articles

Ultrasound had high accuracy in measuring hip joint capsule thickness

BackgroundThe hip joint capsule is an essential component of hip joint function and stability, and its thickness is closely associated with certain medical conditions, surgical outcomes, and rehabilitation treatments. Currently, in clinical practice, hip joint capsule thickness is predominantly measured using magnetic resonance imaging (MRI), with limited utilization of ultrasound examinations for this purpose.MethodsWe retrospectively evaluated patients who visited our Sports Medicine Department between February 2017 and March 2023 and underwent both hip joint MRI and ultrasound imaging on the same side. All patients had undergone preoperative hip joint MRI and ultrasound examinations, with the time gap between the two examinations not exceeding three months. Measurements of hip joint capsule thickness were taken on both MRI and ultrasound images for the same patients to analyze their consistency. Additionally, we measured the alpha angle, lateral center-edge angle, acetabular anteversion angle, and femoral anteversion angle of the patients’ hip joints and analyzed their correlation with hip joint capsule thickness measure by ultrasound.ResultsA total of 307 patients were included in this study, with hip joint capsule thickness measured by MRI and ultrasound being 5.0 ± 1.2 mm and 5.0 ± 1.5 mm, respectively. The Bland-Altman analysis demonstrates good agreement or consistency. The paired t-test resulted in a p-value of 0.708, indicating no significant statistical difference between the two methods. The correlation analysis between acetabular anteversion angle and ultrasound-measured capsule thickness yielded a p-value of 0.043, indicating acetabular anteversion angle and capsular thickness may have negative correlation.ConclusionsThe measurements of joint capsule thickness obtained through ultrasound and MRI showed good consistency, suggesting that ultrasound can be used in clinical practice as a replacement for MRI in measuring hip joint capsule thickness. There was a significant correlation between acetabular anteversion angle and hip joint capsule thickness, indicating potential for further research in this area.

Fast and Accurate Registration of the Proximal Femurs in Bilateral Hip Joint Images by Using the Random Sub-Sample Points

Background and ObjectiveAs is known, point clouds representing the objects are frequently used in object registration. Although the objects can be registered by using all the points in the corresponding point clouds of the objects, the registration process can also be achieved with a smaller number of the landmark points selected from the entire point clouds of the objects. This paper introduces a research study focusing on the fast and accurate rigid registration of the bilateral proximal femurs in bilateral hip joint images by using the random sub-sample points. For this purpose, Random Point Sub-sampling (RPS) was analyzed and the reduced point sets were used for an accurate registration of the bilateral proximal femurs in coronal hip joint magnetic resonance imaging (MRI) slices. MethodsIn registration, bilateral proximal femurs in MRI slices were registered rigidly by performing a process consisting of three main phases named as MR image preprocessing, proximal femur registration over the random sub-sample points and MR image postprocessing. In the stage of the MR image preprocessing, segmentation maps of the bilateral proximal femurs are obtained as region of interest (RoI) images from the entire MRI slices and then, the edge maps of the segmented proximal femurs are extracted. In the registration phase, the edge maps describing the proximal femur surfaces are represented as point clouds initially. Thereafter, the RPS is performed on the proximal femur point clouds and the number of points representing the proximal femurs is reduced at different ratios. For the registration of the point clouds, the Iterative Closest Point (ICP) algorithm is performed on the reduced sets of points. Finally, the registration procedures are completed by performing MR image postprocessing on the registered proximal femur images. ResultsIn performance evaluation tests performed on healthy and pathological proximal femurs in 13 bilateral coronal hip joint MRI slices of 13 Legg-Calve-Perthes disease (LCPD) patients, bilateral proximal femurs were successfully registered with very small error rates by using the reduced set of points obtained via the RPS and promising results were achieved. The minimum error rate was observed at RPS rate of 30% as the value of 0.41 (±0.31)% on all over the bilateral proximal femurs evaluated. When the range of RPS rate of 20-30% is considered as the reference, the elapsed time in registration can be reduced by almost 30-40% compared to the case where all the proximal femur points were included in registration. Additionally, it was observed that the RPS rate should be selected as at least 25% to achieve a successful registration with an error rate below 1%. ConclusionIt was concluded from the observed results that a more successful and faster registration can be accomplished by selecting fewer points randomly from the point sets of proximal femurs instead of using all the points describing the proximal femurs. Not only an accurate registration with low error rates was performed, but also a faster registration process was performed by means of the limited number of points that are sub-sampled randomly from the whole point sets.

Magnetic Resonance Imaging (MRI) in Diagnosis of Hip Joint Disability in Adults

AbstractBackground: Painful hip is a common problem in absence of a known acute trauma. MRI is a method of choice in detection of different causes of hip pain causing hip joint disability in adults including osseous, chondral and soft tissue abnormalities.Aim of Study: This prospective study was conducted to evaluate the role of Magnetic Resonance Imaging (MRI) in diagnosis of different causes of hip joint disability in adults.Patients and Methods: This study was conducted on 42 patients (22 females and 20 males) with age ranged from 18- 68 years (mean of 41 years). All patients was subjected to plain X-ray and MRI of hip joint in different sequences, with additional post contrast (axial and coronal T1 WI) in 6 patents. Patient history, clinical examination of the diseased hip, and laboratory investigations were performed.Results: According to final results: 12 patients (28.6% of 42 patients) presented clinically with hip pain but had negative plain X-ray and MRI findings, while other 30 patients of them (71.4%) their MRI diagnoses were as follows: Avascular necrosis in 10 (33.3%), transient osteoporosis in 4 (13%), osteoarthritis in 3 (10%), inflammatory arthritis in 2 (6.7%), traumatic condition in 3 (10%) and bone tumors in 8 (27%).Conclusion: MRI of the hip joint is an essential imaging modality in detection of different hip joint pathologies espe-cially in patients presented clinically with hip pain but with negative conventional radiography.

Determination of correlation between alpha angle and herniation pit in healthy adults on hip MRI

The purpose of this study was to investigate the association between alpha angle and herniation pit (HP) in healthy adults on hip magnetic resonance imaging (MRI). Between May 2016 and September 2018, 502 hip joint MRIs of 251 healthy adults (aged between 19 and 82 years) were retrospectively evaluated to determine the presence of HP of the femoral neck. Femoral neck alpha angles were also measured. Possible relationships between herniation pit and age, sex, sided-ness, and alpha angle were investigated. One hundred twenty-four males and 127 females were included, and the mean age was 40.96 ± 12.85. HPs were present in 20 of the 502 hips, a prevalence of 3.98 % (45 % at right and 55 % left hips). The herniation pit sizes were ranged from 2 to 9.6 mm; the average value was 5.1±2.2 mm. The average value of the alpha angle of 502 hips was 50.42 ± 5.91°. The alpha angle was ≥ 55 degrees in sixty-seven (13.35 %) of 502 patients. No correlation was found between herniation pit and age, sex, side (right or left hip) and alpha angle degrees. No statistically significant association was found between alpha angle ≥ 55 degrees and the actual size of the herniation pit. There is no correlation between age, sex, or alpha angle ≥ 55 degrees and the prevalence of herniation pit in healthy hips. HP formation is an incidental radiologic finding and unrelated to the alpha angle.

Simultaneous multi-slice MR imaging of the hip at 3\u2009T to reduce acquisition times and maintain image quality

BackgroundNewly developed simultaneous multi-slice (SMS) scans are now being introduced as a clinical application in neuroimaging. We examined the feasibility of SMS scans for joint imaging. The purpose of the present study was to prospectively compare the resolution and specific absorption rate (SAR) obtained using SMS to those of conventional methods in hip joint magnetic resonance imaging (MRI) and establish whether imaging times may be reduced using SMS in 3 T MRI and if image quality is affected.MethodsTwenty-one patients (4 men and 17 women, average age, 51.5 years, range: 22 to 76 years) with hip pain underwent MR examinations of the unilateral hip joint. Three board-certified radiologists independently and blindly evaluated the images obtained with and without SMS using window and level settings and magnification according to personal preferences. Individual SAR values were measured for each protocol. A Wilcoxon signed-rank test and a t-statistic test were used for statistical analyses. Signal-to-noise ratio (SNR) was also compared using a phantom.ResultsSMS imaging maintained equivalent image quality to conventional imaging for evaluating the morphology of the hip joint, and also reduced imaging times by approximately 40%. SMS images had significantly higher SAR values than conventional images. The rate of difference (SMS/conventional) in SNR ranged between 80 and 111%.ConclusionsBased on its significantly lower acquisition times and the maintenance of similar image quality to conventional imaging, SMS may be applied to morphological evaluations of hip joint disorders without significantly increasing SAR.

Revision of Pelvic Rotation Angle and One Idea for Improving Reproducibility of Hip Joint Radiographic Images (False Profile View)

Radiographic images of the hip joint can include a false profile view when the foot of the affected side is positioned parallel to the detector plane and the pelvic rotation angle is 65°. However, to the best of our knowledge, pelvic rotation angle has yet to be adequately investigated. The present study aimed to improve radiographic imaging reproducibility by testing pelvic rotation angles using the pubic symphysis and greater trochanter as a guide. The pubic bone angles were 50°-60° independent of gender or age in approximately 70% of 210 hip joints examined by computed tomography. When the line connecting the centers of the femoral neck and the pubic symphysis was based on a detector plane during hip joint magnetic resonance imaging of 12 healthy volunteers, pubic bone angles were approximately 65° and 62° when rotated outwards at 20° and 30°, respectively. Based on the detector plane, the difference between the angle at the intersection of the line connecting the femoral neck center and the pubic symphysis center and the angle at the intersection of the line connecting the pubic symphysis superior margin and the greater trochanter was <4° at external rotation angles of 10°, 20°, and 30°. The foot of the affected side corresponding to the detector plane in front of the body at approximately 65° and the second metatarsal at a pelvic rotation angle when collimated was rotated 25° outwards. Radiation is incident on the pubic symphysis and the greater trochanter can be used as an ejection point.

Evaluation of Cam-type femoroacetabular impingement by ultrasound

In the diagnosis of femoroacetabular impingement (FAI), magnetic resonance imaging (MRI) and X-ray are widely accepted methods for detection. When evaluating the hip head-neck junction using MRI, oblique axial sequences are required. However, the construction and analysis of these images are restricted to specialist radiologists and surgeons in the field of hip joint MRI. This study sought to investigate whether ultrasound, a simple and inexpensive method, can be used as a reliable tool for diagnosing Cam-type FAI. Forty patients, with a mean age of 39years (range, 18-61years), were consecutively included in this prospective study, following a diagnosis of Cam-type FAI on an oblique axial MRI. All patients underwent ultrasound examination in the ventral longitudinal section at 20° external rotation, neutral position and 20° internal rotation. The alpha angle, anterior offset, offset-ratio, and anterior femoral distance (AFD) were measured using MRI and ultrasound. No significant differences were detected between the alpha angle on MRI and that using ultrasound in the neutral position or in 20° internal rotation, with strong correlations observed between these parameters (r = 0.67 for neutral position, r = 0.77 for 20° internal rotation). The Pearson's correlation coefficient for the alpha angle on MRI and the ratio of AFD/anterior offset on ultrasound in internal rotation was 0.76 (p < 0.0001). The results show strong correlations between MRI and ultrasound measurements in patients with Cam-type FAI. Consequently, ultrasound may provide a useful tool for the early diagnosis of Cam-type FAI in daily practice.