Predictive value of crossover sign for outcome of ultrasound-guided vacuum aspiration in women with Cesarean scar pregnancy.

OBJECTIVE: To examine the value of the crossover sign (COS) in predicting treatment outcome in women with a Cesarean scar pregnancy (CSP) who were treated with ultrasound-guided vacuum aspiration. METHODS: This was a retrospective cohort study of women with CSP who underwent ultrasound-guided vacuum aspiration. Based on the relationship between the gestational sac, Cesarean scar and anterior wall of the uterus, CSPs were classified by COS type. Analysis was conducted to investigate the association between COS type (COS-1, COS-2) and treatment outcome. The incidence of treatment failure, retained pregnancy tissue, secondary therapy and bleeding ≥ 200 mL were analyzed. RESULTS: In total, 181 eligible patients with CSP, including 90 (49.7%) women with COS-1 and 91 (50.3%) women with COS-2, were analyzed. COS-1 patients had a higher incidence of treatment failure compared with COS-2 patients (25.6% vs 8.8%; P = 0.003), as well as higher rates of retained pregnancy tissue (18.9% vs 6.6%; P = 0.013), secondary therapy (20.0% vs 6.6%; P = 0.002) and bleeding of ≥ 200 mL (13.3% vs 4.4%; P = 0.034). COS-1 and a large gestational sac (30.1-50.0 mm or >50.0 mm in diameter) were associated independently with increased risk of treatment failure (odds ratio, 4.57 (95% CI, 1.66-12.56); P = 0.003, 4.34 (95% CI, 1.35-13.94); P = 0.014 and 10.50 (95% CI, 2.54-43.46); P = 0.001, respectively). CONCLUSIONS: Ultrasound evaluation of the relationship between the gestational sac and the endometrial line (COS classification) in women with CSP may help to predict treatment outcome among those undergoing vacuum aspiration. Among COS-1 patients, especially those with a gestational sac diameter of >30.0 mm, vacuum aspiration may be discouraged. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Value of first-trimester ultrasound in prediction of third-trimester sonographic stage of placenta accreta spectrum disorder and surgical outcome.

OBJECTIVES: To explore whether early first-trimester ultrasound can predict the third-trimester sonographic stage of placenta accreta spectrum (PAS) disorder and to elucidate whether combining first-trimester ultrasound findings with the sonographic stage of PAS disorder can stratify the risk of adverse surgical outcome in women at risk for PAS disorder. METHODS: This was a retrospective analysis of prospectively collected data from women with placenta previa, and at least one previous Cesarean delivery (CD) or uterine surgery, for whom early first-trimester (5-7 weeks' gestation) ultrasound images could be retrieved. The relationship between the position of the gestational sac and the prior CD scar was assessed using three sonographic markers for first-trimester assessment of Cesarean scar (CS) pregnancy, reported by Calí et al. (crossover sign (COS)), Kaelin Agten et al. (implantation of the gestational sac on the scar vs in the niche of the CS) and Timor-Tritsch et al. (position of the center of the gestational sac below vs above the midline of the uterus), by two different examiners blinded to the final diagnosis and clinical outcome. The primary aim of the study was to explore the association between first-trimester ultrasound findings and the stage of PAS disorder on third-trimester ultrasound. Our secondary aim was to elucidate whether the combination of first-trimester ultrasound findings and sonographic stage of PAS disorder can predict surgical outcome. Logistic regression analysis and area under the receiver-operating-characteristics curve (AUC) were used to analyze the data. RESULTS: One hundred and eighty-seven women with vasa previa were included. In this cohort, 79.6% (95% CI, 67.1-88.2%) of women classified as COS-1, 94.4% (95% CI, 84.9-98.1%) of those with gestational-sac implantation in the niche of the prior CS and 100% (95% CI, 93.4-100%) of those with gestational sac located below the uterine midline, on first-trimester ultrasound, were affected by the severest form of PAS disorder (PAS3) on third-trimester ultrasound. On multivariate logistic regression analysis, COS-1 (odds ratio (OR), 7.9 (95% CI, 4.0-15.5); P < 0.001), implantation of the gestational sac in the niche (OR, 29.1 (95% CI, 8.1-104); P < 0.001) and location of the gestational sac below the midline of the uterus (OR, 38.1 (95% CI, 12.0-121); P < 0.001) were associated independently with PAS3, whereas parity (P = 0.4) and the number of prior CDs (P = 0.5) were not. When translating these figures into diagnostic models, first-trimester diagnosis of COS-1 (AUC, 0.94 (95% CI, 0.91-0.97)), pregnancy implantation in the niche (AUC, 0.92 (95% CI, 0.89-0.96)) and gestational sac below the uterine midline (AUC, 0.92 (95% CI, 0.88-0.96)) had a high predictive accuracy for PAS3. There was an adverse surgical outcome in 22/187 pregnancies and it was more common in women with, compared to those without, COS-1 (P < 0.001), gestational-sac implantation in the niche (P < 0.001) and gestational-sac position below the uterine midline (P < 0.001). On multivariate logistic regression analysis, third-trimester ultrasound diagnosis of PAS3 (OR, 4.3 (95% CI, 2.1-17.3)) and first-trimester diagnosis of COS-1 (OR, 7.9 (95% CI, 4.0-15.5); P < 0.001), pregnancy implantation in the niche (OR, 29.1 (95% CI, 8.1-79.0); P < 0.001) and position of the sac below the uterine midline (OR, 6.6 (95% CI, 3.9-16.2); P < 0.001) were associated independently with adverse surgical outcome. When combining the sonographic coordinates of the three first-trimester imaging markers, we identified an area we call high-risk-for-PAS triangle, which may enable an easy visual perception and application of the three methods to prognosticate the risk for CS pregnancy and PAS disorder, although it requires validation in large prospective studies. CONCLUSIONS: Early first-trimester sonographic assessment of pregnancies with previous CD can predict reliably ultrasound stage of PAS disorder. Combination of findings on first-trimester ultrasound with second- and third-trimester ultrasound examination can stratify the surgical risk in women affected by a PAS disorder. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Association of hemorrhage at termination in caesarean scar pregnancy using the crossover sign of ultrasound image.

PURPOSE: To analyze whether crossover sign (COS) can help predict the risk of bleeding during surgical evacuation in patients with caesarean scar pregnancy (CSP). METHODS: This study retrospectively analyzed the clinical presentations, ultrasound images and treatment outcomes of patients with CSP. The relationship among the gestational sac, caesarean scar and the anterior uterine wall, defined as the COS, was analyzed to predict the risk of severe bleeding during surgical evacuation in these patients. All patients were categorized according to the relationship between the endometrial line and the superior-inferior diameter of the gestational sac into crossover sign-1 and crossover sign-2 groups. The Mann-Whitney U test was used to compare the data with non-normal distribution, and logistic regression analysis was performed to identify the correlates of severe bleeding. RESULTS: A total of 74 patients were included. In COS-1 group (n = 21), 16 (76.19%) patients suffered heavy bleeding(≥200 mL) during surgical evacuation, while COS-2 group (n = 53) had only 1(11.89%) patient complaint of heavy bleeding (≥200 mL) (P < 0.01). Adverse surgical outcomes were more common in women with COS-1. Logistic regression analysis showed that COS-1 (OR, 7.93; 95% CI, 1.35-46.67) was independently associated with severe bleeding. CONCLUSION: COS can help predict who has a higher risk of severe hemorrhage in patients with CSP and guide the clinical treatment selection for optimal management of this condition.

Can the crossover sign be a reliable marker of global retroversion of the acetabulum?

OBJECTIVE: Diagnosis of acetabular retroversion based on crossover sign in the anteroposterior radiograph of the hip joint is well described. Accuracy of the crossover sign to identify global retroversion of the acetabulum in comparison to version of the acetabulum in reconstructed three-dimensional computed tomography (3D CT) scan of the hip was the aim of this study. MATERIALS AND METHODS: X-rays of 500 hips were assessed regarding presence of crossover sign and its location in the upper, middle, or lower third of the acetabulum. Mean of anteversion and true retroversion (defined as less than one standard deviation below the mean of acetabular anteversion) of the acetabulum using reconstructed 3D CT scan by mathematical software was determined among 500 hips. The positive and negative crossover signs were compared to the retroversion obtained by CT scan. RESULTS: The average of acetabular anteversion was 12.5 ± 4.2 degrees. True global retroversion in 3D CT scans was defined as a version below 8.3 degrees. Although positive crossover sign was seen in 193 out of 500 (38 %), only 69 out of 500 (13.8 %) of hips had version below 8.3 (true retroversion) and 124 subjects had an acetabular version above 8.3. The sensitivity and specificity of crossover signs were about 82 and 70 %, respectively. CONCLUSIONS: The crossover sign could pick up hips with less than normal anteversion with acceptable sensitivity but it has no enough specificity for being used as the sole indication for treatment.

How to Best Identify Acetabular Retroversion on Radiographs: Thresholds to Guide Clinical Practice.

BACKGROUND: Acetabular retroversion is associated with impingement and instability. An adequate interpretation of acetabular version and coverage on radiographs is essential to determine the optimal treatment strategy (periacetabular osteotomy vs hip arthroscopic surgery). The crossover sign (COS) has been associated with the presence of acetabular retroversion, and the anterior wall index (AWI) and posterior wall index (PWI) assess anteroposterior acetabular coverage. However, the radiographic appearance of the acetabulum is sensitive to anterior inferior iliac spine (AIIS) morphology and pelvic tilt (PT), which differs between the supine and standing positions. PURPOSE: To (1) identify differences in the acetabular appearance between the supine and standing positions among patients presenting with hip pain; (2) determine factors (acetabular version, AIIS morphology, and spinopelvic characteristics) associated with the crossover ratio (COR), AWI, and PWI; and (3) define relevant clinical thresholds to guide management. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients who presented to a hip preservation surgical unit (n = 134) were included (mean age, 35 ± 8 years; 58% female; mean body mass index, 27 ± 6). All participants underwent supine and standing anteroposterior pelvic radiography to assess the COS, COR, AWI, and PWI as well as standing lateral radiography to determine standing PT. Computed tomography was used to measure supine PT, acetabular version, and AIIS morphology. Acetabular version was measured at 3 transverse levels, corresponding to the 1-, 2-, and 3-o'clock positions. The correlation between radiographic characteristics (COR, AWI, and PWI) and acetabular version, AIIS morphology, and PT was calculated using the Spearman correlation coefficient. Receiver operating characteristic curve analysis was performed to define thresholds for the COR, AWI, and PWI to identify retroversion (version thresholds: <10°, <5°, and <0°). RESULTS: The COS was present in 55% of hips when supine and 30% when standing, with a mean difference in the COR of 12%. The supine COR (rho = -0.661) and AWI/PWI ratio (rho = -0.618) strongly correlated with acetabular version. The COS was more prevalent among patients with type 2 AIIS morphology (71%) than among those with type 1 AIIS morphology (43%) (P = .003). COR thresholds of 23% and 28% were able to identify acetabular version <5° (sensitivity = 81%; specificity = 80%) and <0° (sensitivity = 88%; specificity = 85%), respectively. An AWI/PWI ratio >0.6 was able to reliably identify acetabular version <0° (sensitivity = 83%; specificity = 84%). In the presence of a COR >30% and an AWI/PWI ratio >0.6, the specificity to detect retroversion was significantly increased (>90%). CONCLUSIONS: The presence of the COS was very common among patients with hip pain. False-positive results (high COR/normal version) may occur because of AIIS morphology/low PT. Relevant thresholds of COR >30% and AWI/PWI ratio >0.6 can help with diagnostic accuracy. In cases in which either the COR or AWI/PWI ratio is high, axial cross-sectional imaging can further help to avoid false-positive results.

Cesarean Scar Pregnancy: A systematic review on expectant management.

A Cesarean Scar Pregnancy (CSP) is a variant of uterine ectopic pregnancy defined by full or partial implantation of the gestational sac in the scar of a previous cesarean section. The continuous increase of Cesarean Deliveries is causing a parallel increase in CSP and its complications. Considering its high morbidity, the most usual recommendation has been termination of pregnancy in the first trimester; however, several cases progress to viable births. The aim of this systematic review is to evaluate the outcome of CSP managed expectantly and understand whether sonographic signs could correlate to the outcomes. An online-based search of PubMed and Cochrane Library Databases was used to gather studies including women diagnosed with a CSP who were managed expectantly. The description of all cases was analysed by the authors in order to obtain information for each outcome. 47 studies of different types were retrieved, and the gestational outcome was available in 194 patients. Out of these, 39 patients (20,1%) had a miscarriage and 16 (8,3%) suffered foetal death. 50 patients (25,8%) had a term delivery and 81 (41,8%) patients had a preterm birth, out of which 27 (13,9%) delivered before 34 weeks of gestation. In 102 (52,6%) patients, a hysterectomy was performed. Placenta Accreta Spectrum (PAS) was a common disorder among CSP and was linked to a higher rate of complications such as foetal death, preterm birth, hysterectomy, haemorrhagic morbidity and surgical complications. Some of the analysed articles showed that sonographic signs with specific characteristics, such as type II and III CSP classification, Crossover Sign - 1, "In the niche" implantation and lower myometrial thickness could be related to worse outcomes of CSP. This article provides a good understanding of CSP as an entity that, although rare, presents with a high rate of relevant morbidity. It is also understood that pregnancies with confirmed PAS had an even higher rate of morbidity. Some sonographic signs were shown to predict the prognosis of these pregnancies and further investigation is necessary to validate one or more signs so they can be used for a more reliable counselling of women with CSP.

Arthroscopic Treatment and Outcomes of Borderline Dysplasia With Acetabular Retroversion: A Matched-Control Study From the MASH Study Group.

BACKGROUND: Although acetabular retroversion (AR) occurs in dysplasia, management of the crossover sign (COS) or outcomes in borderline dysplasia (BD) with AR have not been reported. PURPOSE: To report any differences in the management of the COS in BD and nondysplastic hips and to report comparative outcomes of BD with AR with matched controls with BD or AR (ie, focal pincer femoroacetabular impingement [FAI]). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A multicenter matched-pair study was performed with data from a large prospectively collected database. Inclusion criteria were patients who had undergone primary unilateral hip arthroscopy including labral repair for FAI and/or chondral pathology without significant osteoarthritis (ie, Tönnis grade 0 or 1). The study group (BD+AR) was defined radiographically by lateral center-edge angle (LCEA) on standing anteroposterior pelvis of 18° to 25° and positive COS. A 1:1:1 matching on age, sex, and body mass index was performed with a control group with BD and another control group with AR (LCEA, >25°+COS). Acetabuloplasty rates were determined for each group. Mean 2-year outcomes including the 12-Item International Hip Outcome Tool (iHOT-12), minimally clinical important difference (MCID), substantial clinical benefit (SCB), and Patient Acceptable Symptom State (PASS) scores were compared. Subanalysis of the study group both with and without acetabuloplasty was performed. RESULTS: There were 69 patients, with 23 in the study group and 23 in each control group. The effect of dysplasia with or without the presence of the COS resulted in changes in acetabuloplasty rates, with 0% performed in the BD group, 35% in the BD+AR study group, and 91% in the AR group (P = .001). Arthroscopic outcomes demonstrated similar and significant mean 2-year improvement of iHOT-12 patient-reported outcomes, MCID, SCB, and PASS scores in the study and both control groups. There was a trend within the study group toward greater postoperative iHOT-12 scores in patients who received anterior-based acetabuloplasty than those who did not receive acetabuloplasty (81.7 and 70.4, respectively; P = .11). CONCLUSION: Acetabular coverage influences the management of the COS, with significantly lower acetabuloplasty rates in BD with AR compared with AR without BD (focal pincer impingement). Symptomatic patients with combined BD and AR had similar significant successful outcomes to those of patients with BD and those with AR (focal pincer impingement), whether treated without acetabuloplasty or, less frequently, with limited anterior-based acetabuloplasty.

Value of Crossover Sign in Anticipating Under-8-week Cesarean Scar Pregnancy Treatment by Foley Insertion Combined with Suction Curettage in Vietnam.

OBJECTIVES: An earlier study completed at TuDu Hospital presented the efficacy of Foley insertion combined with fetal suction curettage at a high rate of success in treatment of cesarean scar pregnancy (CSP) of < 8 weeks, but the efficacy of prognosticating factors for this approach has not been specifically addressed yet, especially crossover sign (COS) on ultrasound. We aimed to investigate the correlation between COS on ultrasound and the treatment results of CSP using Foley insertion combined with fetal suction. MATERIALS AND METHODS: A case-control study of CSPs ≤ 8 weeks treated at TuDu Hospital during September 2017-April 2019 included 63 failures in the case group and 98 successes in the control group. RESULTS: COS-2 + increased the likelihood of treatment success by 4.9 times (95% confidence interval: 1.8-13.5) compared with COS-1 cases. In addition, other factors favoring treatment success with statistical significance included no vascularization at cesarean scar on ultrasound (odds ratio [OR] = 7.1), gestational mass volume ≤4 cm3 (OR = 3.7), and ß-human chorionic gonadotropin at hospital admission ≤ 10,000 mIU/mL (OR = 6.1). CONCLUSION: COS imaging played an important role in the prediction of treatment outcomes for CSP ≤ 8 weeks by the combined approach of Foley insertion and fetal suction curettage.

Diagnostic Value of Ischial Spine Sign in Patients with Acetabular Retroversion.

BACKGROUND: Acetabular Retroversion (AR) is a hip disorder and one of the causes of pain in this area. Evaluation of positive Cross Over Sign (COS) on AP X-Rays of the hip is currently the best method of diagnosis of AR. Several studies have measured co-existence of Ischial Spine Sign (ISS) in patients with AR. In this study we evaluated the diagnostic value of ISS in confirmation of AR and compared it with the diagnostic value of COS. METHODS: In this study, 4120 AP hip X-Rays from Akhtar Hospital, Shahid Beheshti University of Medical Sciences, Tehran, were studied. Based on radiologic criteria, 1180 X-Rays were considered as standards and evaluated for ISS, COS and PWS (Posterior Wall Sign). Data analysis was done for correlation between ISS and COS. RESULTS: A total of 1180 out of 4120 X-Rays were considered as standard; among which, 86 were diagnosed with AR based on positive COS in presence of PWS. Both ISS and COS were positive concurrently in 69 X-Rays. ISS was positive in absence of COS in 11 X-rays. No significant difference in diagnostic value for diagnosis of acetabular retroversion was found between ISS and COS (P<0.05). CONCLUSION: According to our results, both ISS and COS signs can be employed for diagnosis of AR (acetabular retroversion). Considering the absence of a significant difference between these two signs in confirmation of AR, it can be perceived that the diagnostic value of ISS in confirmation of AR is equal to COS. Validation of the mentioned results requires further studies.

Relationship between crossover sign and anterior center-edge angle.

PURPOSE: The aim of this study was to evaluate the relationship between the anterior center-edge angle (ACEA) and lateral center-edge angle (LCEA) and crossover ratio. METHODS: Consecutive patients presenting for evaluation of hip pain were reviewed. The following measurements were recorded and analyzed: Crossover ratio, LCEA, ACEA, and alpha-angle. RESULTS: 68 patients met inclusion criteria. The only statistically significant radiographic measurement when stratified by gender was alpha angle (P < 0.001). There was moderate correlation between crossover ratio and ACEA and LCEA with coefficients of -0.48 and -0.48, respectively. CONCLUSION: A correlation exists between crossover ratio and ACEA and LCEA.

Validation of CT image-based software for three-dimensional measurement of acetabular coverage profile.

BACKGROUND: Plain radiography, 2-dimensional (2D) magnetic resonance imaging (MRI), and computed tomography (CT) do not precisely display morphology and acetabular coverage in developmental dysplasia of the hip or pincer-type femoroacetabular impingement. Pelvic position and pelvic tilt affect assessment of the acetabular parameters, leading to misinterpretation. OBJECTIVE: We tested a 3-dimensional (3D) CT evaluation script to calculate the crossover sign (COS), acetabular coverage and morphology. METHODS: To test the method, we constructed a phantom pelvic model, in which the acetabulum was mounted at different coverages of the femoral head, and simulated a COS and the acetabular morphology. Additionally we examined the reliability and objectivity of this method in ten patients with CT scans of the pelvis for conditions unrelated to hip disorders. RESULTS: We obtained an average accuracy of the 3D CT evaluation script of -0.37∘ (range -3.84 to 3.88; SD ± 1.43) for morphology, and 0.002% (range -7.28% to 6.90%; SD ± 1.60%) for coverage of the femoral head. Significant correlation between the expected and calculated COS (p= 0.01) was found. CONCLUSIONS: Our 3D CT evaluation script permits precise evaluation of the acetabular coverage profile, the presence or absence of a COS and acetabular morphology, independent of patient positioning or pelvic tilt.

Clinical Outcomes of Hip Arthroscopy in Radiographically Diagnosed Retroverted Acetabula.

BACKGROUND: Symptomatic global retroversion of the acetabulum, as diagnosed on plain radiographs of the pelvis, has traditionally been treated with reverse periacetabular osteotomy, which improves posterior undercoverage and eliminates the anterior pincer lesion. There is a paucity of literature on hip arthroscopy in this group, secondary to theoretical concern of iatrogenic dysplasia, subsequent instability, and arthritis. PURPOSE: To evaluate the outcomes of hip arthroscopy for patients with a radiographic diagnosis of acetabular retroversion, using patient-reported outcomes, visual analog scale (VAS), patient satisfaction, and pre- and postoperative Tönnis grades. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Pre- and postoperative data were prospectively collected and retrospectively reviewed for patients who underwent hip arthroscopy at 1 institution between June 2008 and February 2012. Data were analyzed for patients who had adequate radiographs of the pelvis that demonstrated global acetabular retroversion and who were treated with arthroscopic surgery. Complications were tracked in this institution's database. The modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score (HOS)-activities of daily living subscale, and HOS-sport-specific subscale, and VAS were analyzed preoperatively and at latest follow-up. Level of postoperative satisfaction was assessed on a scale of 0 to 10. Pre- and postoperative alpha angle, lateral center-edge angle, anterior center-edge angle, crossover percentage, and Tönnis grade were recorded. Tönnis grade at latest follow-up was utilized to determine progression of osteoarthritis. RESULTS: A total of 82 hips among 78 patients were identified who met the listed criteria. The mean age of the patients was 23 years, and the mean follow-up was 39 months. These patients showed statistically significant improvement in modified Harris Hip Score (preoperative to ≥2-year follow-up: 65 to 81), Nonarthritic Hip Score (65 to 86), HOS-activities of daily living subscale (69 to 88), HOS-sport-specific subscale (47 to 76), and VAS (5.9 to 2.5) (P < .0001). In terms of satisfaction with the surgery, they had an mean score of 7.4. There were 3 minor complications, none of which required reoperation. One patient underwent hip arthroplasty at 6 months after hip arthroscopy. Fifteen patients had >2-year radiographic follow-up; none of these patients had an increase in Tönnis grade as compared with the preoperative state. CONCLUSION: This study demonstrates that hip arthroscopy can successfully treat femoroacetabular impingement associated with a globally retroverted acetabulum at a minimum 2-year follow-up. Survivorship was 99% at 2 years, with 1 patient requiring further surgery in the form of hip arthroplasty. There was no noted progression of Tönnis grade at final follow-up. The procedure was extremely safe, with a minor complication rate of 3.6%.

Coxa profunda in the diagnosis of pincer-type femoroacetabular impingement and its prevalence in asymptomatic subjects.

In many papers, the diagnosis of pincer-type femoroacetabular impingement (FAI) is attributed to the presence of coxa profunda. However, little is known about the prevalence of coxa profunda in the general population and its clinical relevance. In order to ascertain its prevalence in asymptomatic subjects and whether it is a reliable indicator of pincer-type FAI, we undertook a cross-sectional study between July and December 2013. A total of 226 subjects (452 hips) were initially screened. According to strict inclusion criteria, 129 asymptomatic patients (257 hips) were included in the study. The coxa profunda sign, the crossover sign, the acetabular index (AI) and lateral centre-edge (LCE) angle were measured on the radiographs. The median age of the patients was 36.5 years (28 to 50) and 138 (53.7%) were women. Coxa profunda was present in 199 hips (77.4%). There was a significantly increased prevalence of coxa profunda in women (p < 0.05) and a significant association between coxa profunda and female gender (p < 0.001) (92% vs 60.5%). The crossover sign was seen in 36 hips (14%), an LCE > 40° in 28 hips (10.9%) and an AI < 0º in 79 hips (30.7%). A total of 221 normal hips (79.2%) (normal considering the crossover) had coxa profunda, a total of 229 normal hips (75.5%) (normal considering the LCE) had coxa profunda and a total of 178 normal hips (75.3%) (normal considering AI) had coxa profunda. When the presence of all radiological signs in the same subject was considered, pincer-type FAI was found in only two hips (one subject). We therefore consider that the coxa profunda sign should not be used as a radiological indicator of pincer-type FAI. We consider profunda to be a benign alteration in the morphology of the hip with low prevalence and a lack of association with other radiological markers of FAI. We suggest that the diagnosis of pincer-type FAI should be based on objective measures, in association with clinical findings.

Femoro-acetabular impingement: the diagnosis-a review.

BACKGROUND: The recognition of the importance of femoral acetabular impingement (FAI) as a potential cause of hip pain has been stimulated by major efforts to salvage hip joints by reconstruction in order to prevent or delay the need for replacement. The purpose of this review is to define the nature of FAI, the various types, and how to make the diagnosis. METHODS: The review describes the characteristics of the hip that cause FAI and emphasizes understanding that the femoral and acetabular components normally function as a unit, complementing each other. RESULTS/CONCLUSION: The methods of making the diagnosis of FAI and their limitations are described. If the acetabulum and femur are considered to be independent of each other, conflict may occur, hindering function, and not be apparent. The increasing frequency of making this diagnosis based on abnormal anatomy on one side of the joint, often in face of unclear physical findings, can bring the diagnosis into question. FAI seen in Perthes disease and acetabular dysplasia is explained. Knowing how to analyze the hip, being aware of the limitations of various available clinical and diagnostic studies, and recognizing the continued and ever-changing extensive body of literature is important and challenging. This primer is just the beginning.

Relación entre el signo de entrecruzamiento y el ángulo de versión acetabular en tomografía axial computada / Association between the crossover sign and the acetabular version angle in axial computed tomography

Introduction.The crossover sign (CS) is proposed in the diagnosis of pincer-type femoroacetabular impingement (FAI). CS occurs in the cranial region of the acetabulum while the acetabular version angle (AV) is measured in the region where the acetabulum becomes deeper. Objective. To determine whether AV values measured in cranial regions using the classical measures relate better to the findings for positive CS. Material and Methods. Cross sectional study in asymptomatic patients. Images were obtained by CT of the abdomen and pelvis. They were recored in anterior-posterior reconstruction the CS and in axial reconstruction the AV angle. Logistic regression models for measuring AV in 7 cephalic levels to caudal with 95 percent CI were estimated. Results. 104 patients were measured. At Level 3 an area under ROC curve 0.81 (0.74-0.87), cutoff value of 11.2 degrees with sensitivity of 80.0 percent and specificity of 73.0 percent, was obtained. Conclusion. AV at level 3 has higher diagnostic capacity for the presence of positive CS.

Introducción. El signo de entrecruzamiento (SE) es propuesto en el diagnóstico imagenológico del pinzamiento Femoroacetabular tipo Pincer. El SE se produce en la región craneal del acetábulo, mientras que el ángulo de versión acetabular (VA) se mide en la región donde el acetábulo se hace más profundo. Objetivo. Determinar si valores de VA medidos en regiones craneales a la medida clásica se relacionan mejor al hallazgo de SE positivo. Material y Método. Estudio transversal en pacientes asintomáticos. Se obtuvieron imágenes mediante TC de abdomen y pelvis. Fueron consignados en reconstrucción antero-posterior el SE y en reconstrucción axial el ángulo de VA. Se estimaron modelos de regresión logística para la medición de VA en 7 niveles de cefálico a caudal con IC 95 porciento. Resultados. Fueron medidos 104 pacientes. En nivel 3 se obtuvo un área bajo curva ROC 0.81 (0.74-0.87), valor de corte 11.2 grados con sensibilidad de 80.0 porciento y especificidad de 73.0 porciento. Conclusión. VA en nivel 3 tiene mayor capacidad diagnóstica de la presencia de SE positivo.