Increased tibial tuberosity torsion has the greatest predictive value in patients with patellofemoral instability compared to other commonly assessed parameters.

PURPOSE: The multifactorial nature of patellofemoral instability requires a comprehensive assessment of the affected patients. While an association between tibial tuberosity (TT) torsion and patellofemoral instability is known, its specific effect has not yet been investigated. This study investigated the effect of TT torsion on patellofemoral instability. METHODS: This retrospective cohort study compared patients who underwent surgical intervention for patellofemoral instability and asymptomatic controls. TT torsion was measured in addition to other commonly assessed risk factors for patellofemoral instability using standardised computed tomography (CT) data of the lower extremities. The diagnostic performances of the assessed parameters were evaluated using receiver operating characteristic curve analysis and odds ratios (ORs) were calculated. RESULTS: The patellofemoral instability group consisted of 79 knees, compared to 72 knees in the asymptomatic control group. Both groups differed significantly in all assessed parameters (p < 0.001), except for tibial torsion (n.s.). Among all parameters, TT torsion presented the best diagnostic performance for predicting patellar instability with an area under the curve of 0.95 (95% confidence interval [CI], 0.91-0.98; p < 0.001). A cut-off value of 17.7° yielded a 0.87 sensitivity and 0.89 specificity to predict patellar instability (OR, 55.2; 95% CI, 20.5-148.6; p < 0.001). CONCLUSION: Among the evaluated risk factors, TT torsion had the highest predictive value for patellofemoral instability. Patients with TT torsions ≥ 17.7° showed a 55-fold increased probability of patellofemoral instability. Therefore, TT torsion should be included in the assessment of patients with patellofemoral instability. LEVEL OF EVIDENCE: Level III.

Significant difference in femoral torsion between coronal plane alignment of the knee type 1 and 4.

PURPOSE: The purpose of this study was to find out whether the torsions of the femur and tibia are dependent on the coronal plane alignment of the knee (CPAK) type. METHODS: Five hundred patients (1000 legs) were included, who received a whole leg standing three-dimensional (3D) radiograph using EOS imaging (EOS Imaging, Paris, France). SterEOS software was used for digital reconstruction. Femoral and tibial torsions were determined by analysing 3D reconstructions of each leg. Femoral torsion was defined as the angle between the femoral neck axis (FNA) and the posterior condylar axis (PCA). Tibial torsion was defined as the angle between the axis tangent to the posterior part of the tibia plateau and the transmalleolar axis. Arithmetic hip-knee-ankle angle (aHKA) and joint-line obliquity (JLO) were also determined, allowing each leg to be assigned one of nine possible phenotypes according to CPAK. RESULTS: The mean femoral torsion in CPAK type 1 was significantly higher (+ 2.6° ± 0.8°) than in CPAK type 4 (p = 0.02). All other CPAK types did not differ in the degree of femoral torsions. No differences could be demonstrated for the tibial torsion. CONCLUSION: There is a correlation between the coronal alignment of the lower limb and femoral torsion. This may provide the basis for extending the CPAK classification beyond the coronal plane. LEVEL OF EVIDENCE: Level III.

Left medial liver lobe torsion and postoperative acute gastric rupture in a 2.5-year-old male-castrated Flemish Giant rabbit (Oryctolagus cuniculus).

A 2.5-year-old male-castrated rabbit presented with acute abdominal pain, lethargy, and anorexia. Digital radiography revealed increased left-sided hepatomegaly, gastric dilation, and decreased peritoneal serosal detail. Abdominal ultrasonography identified a torsed left liver lobe, gastric dilation, and peritoneal effusion. Surgery confirmed a left medial liver lobe torsion, with subsequent lobectomy and seven days of hospitalization. The patient re-presented 2 days after discharge and suddenly died while hospitalized, with acute gastric rupture, fulminant peritonitis, and multifocal hepatic infarcts diagnosed on necropsy. We believe this is the first recorded imaging diagnosis of a left medial liver lobe torsion in a rabbit.

Lung lobe torsion associated with chest wall defects in a dog.

An 8-year-old, spayed, female poodle presented with exercise intolerance, lethargy, respiratory distress, retching, hyporexia and diarrhoea. Thoracic radiographs revealed increased opacity in the left cranial thoracic region. The fifth and sixth ribs appeared to be bulging cranially to caudally, and CT and surgical exploration confirmed the presence of a thoracic wall defect in that area. CT showed abrupt occlusion of the bronchus that branches into the left cranial lobe and consolidation of the caudal segment of left cranial lung lobe, which led to the diagnosis of lung lobe torsion. A thoracotomy was performed, the twisted lung lobe was surgically excised, and the defect in the thoracic wall was repaired. Respiratory distress gradually improved after the surgery, and there were no identified complications within the 2-year period following the procedure. Based on our literature search, this is the first reported case of lung lobe torsion caused by a thoracic wall defect in a dog.

Rapid, free-breathing non-contrast MRI for first-line imaging evaluation of ovarian torsion in the emergency department.

BACKGROUND: Transabdominal ultrasound (US) is first-line imaging to evaluate ovaries in girls presenting to the emergency department (ED) with suspected ovarian torsion. Ovaries may be difficult to visualize sonographically; therefore, prompt diagnosis using US alone can be challenging. Rapid MRI as first-line imaging may help streamline patient throughput, especially with increasing MRI availability in the ED. OBJECTIVE: To assess feasibility of rapid MRI for diagnosis of ovarian torsion. MATERIALS AND METHODS: A retrospective, single-center IRB approved study of MRI performed in female pediatric patients presenting with abdominopelvic pain from August 2022 to January 2023. Imaging occurred according to one of three clinical pathways (US-first approach vs MRI-first approach vs US + MRI-second-line approach). A rapid three-sequence free-breathing MRI protocol was utilized. Frequency of ovarian torsion and secondary diagnoses was recorded. Length of MR scan time, time from ED arrival to time of diagnosis, and whether patient had US prior to MR exam were obtained. A historical cohort of patients with US only performed for assessment of ovarian torsion were evaluated for length of the US examination and time from ED arrival to time of diagnosis. Intervals were compared using the uncorrected Fisher's least significant difference and Turkey's multiple comparison tests. RESULTS: A total of 140 MRI exams (mean age 14.6 years) and 248 historical US exams (mean age 13.5 years) were included. Of the patients with MRI, 41 (29%) patients were imaged with US + MRI and 99 (71%) imaged with MRI only; 4% (6/140) MR exams were suspicious for ovarian torsion, with one true positive case (1/6 TP) and 5 false positive cases (5/6 FP); 26.4% (37/140) of exams had secondary diagnoses. Median MRI scan time was 11.4 min (4.4) vs median historical US scan time was 24.1 min (19.7) (P<0.001). Median time from arrival in ED to MRI read was 242 (140). Median time from arrival in ED to US only read was 268 min (148). This was not a statistically significant difference when compared to the MRI only cohort. CONCLUSION: First-line MRI imaging for evaluation of ovarian torsion is a rapid and feasible imaging modality for female patients in the emergent setting.

Fertility preserving management of ovarian torsion.

OBJECTIVE: To analyze characteristics of acute and chronic ovarian torsion, review treatment recommendations, and present possible surgical techniques for fertility preservation in young women. DESIGN: Literature review and demonstration of perioperative management of ovarian torsion using radiologic images and intraoperative video footage. Ovarian torsion is mostly mentioned in context of gynecologic emergencies, where acute ovarian torsion with arterial obstruction leads to ovarian ischemia and necrosis. However, ovarian torsion can also occur as a partial or intermittent torsion with venous and lymphatic obstruction, followed by ovarian swelling. In both cases, surgical management of ovarian torsion commonly includes oophorectomy, although leading guidelines recommend preservation of the ovary. We here aimed to raise awareness for the clinical features of ovarian torsion and demonstrate adequate perioperative management, thereby avoiding surgical overtreatment in young women. SETTING: Medical University of Vienna, Department of Obstetrics and Gynecology. PATIENT(S): We present a case of acute ovarian torsion with a consequently ischemic ovary as well as a case of chronic ovarian torsion with related massive ovarian edema. The patients included in this video gave consent for publication of the video and posting of the video online, including social media, the journal website, scientific literature websites (such as PubMed, ScienceDirect, Scopus, etc.), and other applicable sites. INTERVENTION(S): Laparoscopic management with detorsion of the torquated ovaries, cystectomy on an ischemic ovary and oophoropexy to the pelvic side wall and utero-ovarian ligament to prevent recurrence. MAIN OUTCOME MEASURES: Postoperative relief of pain and normalization of ovarian size and morphology on ultrasound imaging. RESULTS: The current cases show successful conservative surgical management of ovarian torsion, hence preserving hormonal function and fertility in young women. CONCLUSION: Although it is recommended to preserve fertility in young women affected by ovarian torsion, surgical overtreatment by means of oophorectomy is still common in clinical routine. Increasing awareness for the clinical characteristics of acute and chronic ovarian torsion, as well as for the importance of preservation of the ovary, is crucial. We therefore believe that ovarian torsion and its surgical management deserve increased attention in the future.

MRI-based torsion measurement of the lower limb is a reliable and valid alternative for CT measurement: a prospective study.

PURPOSE: The aim of this study was to compare MRI-based torsion measurements of the lower limb to a well-established CT-based assessment in a prospective inter- and intraindividual approach. METHODS: A total of 26 patients (age 28.8 years ± 11.0) were enrolled beginning in January 2021 until August 2022. Inclusion criteria were the clinical indication for torsion measurement of the lower limb. CT and MRI imaging were performed with a standard operating procedure, to ensure that all patients were examined in a standardized position. The examinations were planned on a coronal scout view based on prominent anatomical landmarks. Femoral and tibial torsion were measured individually. Torsion measurements were analysed twice: immediately after examination and after 3 weeks. Subsequently, intra-rater and parallel test reliability was calculated accordingly. RESULTS: High significant results for CT and MRI measurements for both tibia (MRI: r = 0.961; p ≤ 0.001; CT: r = 0.963; p ≤ 0.001) and femur (MRI: r = 0.980; p ≤ 0.001; CT: r = 0.979; p ≤ 0.001) were obtained by calculated intra-rater reliability, showing that measurements were highly consistent for MRI and CT, respectively. Parallel test reliability for time point 1 as well as time point 2 was also highly significant and ranged from r = 0.947 to r = 0.972 (all with p ≤ 0.001, respectively) for both tibia and femur, showing a high concordance between the two measurements. CONCLUSION: Measurement of tibial as well as femoral torsion was comparable for CT and MRI measurement. Therefore, this study supports MRI measurement as an equivalent alternative for CT measurement concerning torsional malalignment to reduce exposure to radiation. LEVEL OF EVIDENCE: Level II.

Sex differences in linear bone measurements occur following puberty but do not influence femoral or tibial torsion.

Torsional, angular, and linear measurements in a paediatric population are clinically important but not well defined and understood. Different methods of measurement and discrepancies between assessors leads to a lack of understanding of what should be defined as typical or atypical for the growing skeleton. From a large dataset of 333 paediatric CT scans, we extracted three-dimensional torsional, angular, and linear measurements from the pelvis, femur, and tibia/fibula. Sex differences in linear measurements were observed in bones of children aged 13+ (around puberty), but femoral and tibial torsion were similar between males and females. The rotational profile (femoral anteversion minus tibial torsion) tended to increase with growth. Epicondylar, condylar, and malleolar widths were smaller in females than males for the same bone length after the age of 13 years, which could explain why females may be more at risk for sport injuries during adolescence. This rich dataset can be used as an atlas for researchers and clinicians to understand typical development of critical rotational profiles and linear bone measurements in children.

Isolated Fallopian Torsion: A Pediatric Case Series.

Isolated fallopian tube torsion is a rare cause of acute abdominal pain in adolescent females. It is known to be a surgical emergency as it may lead to ischemia of the fallopian tube which can result in necrosis, infertility or infection. Presenting symptoms and radiographic findings are vague making diagnosis difficult, often requiring direct visualization in the operating room to make the definitive diagnosis. There has been an increase in this diagnosis at our institution in the previous year prompting compilation of cases and a literature review.

Can Natural Language Processing Improve Adnexal Torsion Predictions?

STUDY OBJECTIVE: To create a decision support tool based on machine learning algorithms and natural language processing (NLP) technology, to augment clinicians' ability to predict cases of suspected adnexal torsion. DESIGN: Retrospective cohort study SETTING: Gynecology department, university-affiliated teaching medical center, 2014-2022. PATIENTS: This study assessed risk-factors for adnexal torsion among women managed surgically for suspected adnexal torsion based on clinical and sonographic data. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The dataset included demographic, clinical, sonographic, and surgical information obtained from electronic medical records. NLP was used to extract insights from unstructured free text and unlock them for automated reasoning. The machine learning model was a CatBoost classifier that utilizes gradient boosting on decision trees. The study cohort included 433 women who met inclusion criteria and underwent laparoscopy. Among them, 320 (74%) had adnexal torsion diagnosed during laparoscopy, and 113 (26%) did not. The model developed improved prediction of adnexal torsion to 84%, with a recall of 95%. The model ranked several parameters as important for prediction. Age, difference in size between ovaries, and the size of each ovary were the most significant. The precision for the "no torsion" class was 77%, with a recall of 45%. CONCLUSIONS: Using machine learning algorithms and NLP technology as a decision-support tool for the diagnosis of adnexal torsion is feasible. It improved true prediction of adnexal torsion to 84% and decreased cases of unnecessary laparoscopy.

Scoring system for predicting ovarian necrosis in adnexal torsion using an ultra-short optimized MRI protocol.

PURPOSE: To evaluate a MRI scoring system predicting haemorrhagic necrosis in adnexal torsion with intraoperative and/or histopathological correlation using an abbreviated and optimized MRI protocol. METHODS: This retrospective observational study includes patients with adnexal torsion who underwent Magnetic Resonance Imaging(MRI) and surgery. T2 sequences were evaluated by three observers of varying experience for following findings: Hypo-intensity of ovarian stroma, around the follicle, cyst wall or ovarian capsule and the twisted pedicle. Hypo-intensities in the above and a thick cyst wall were considered as predictors of necrosis. A scoring system was created based on the number of positive findings. MRI was correlated with intraoperative and histopathological findings. Lesions showing haemorrhagic necrosis were considered true positives. RESULTS: 43 women with torsion were included. 74.4% were secondary to a lead point and 25.4% were without one. Hypointensity score of 2 or more had the highest diagnostic accuracy and inter-reader agreement in predicting necrosis (R1-sensitivity: 92%, specificity: 89%, positive predictive value (PPV): 92% and negative predictive value (NPV): 89%, R2-sensitivity: 92%, specificity: 94%, PPV: 96% and NPV: 90% and R3-sensitivity: 92%, specificity: 83%, PPV: 89% and NPV: 89%). CONCLUSION: In patients with suspected adnexal torsion, optimized MRI using T2 weighted sequences will serve as a rapid and effective single imaging modality for diagnosing adnexal torsion and accurately predicting necrosis thereby triaging the patients for appropriate management.

Sonographic Predictors of Ovarian Torsion in Premenarchal Girls.

STUDY OBJECTIVE: To identify preoperative transabdominal sonographic predictors of surgically confirmed ovarian torsion (OT) in premenarchal girls METHODS: We conducted a retrospective case-control study of 32 premenarchal girls aged 0-12 undergoing surgery for OT (cases) or a non-torsed ovarian mass (controls) from 2006 to 2017 at a single academic center. Cases had ICD-9/10 codes for torsion of the ovary, adnexa, ovarian pedicle, or fallopian tube and surgically confirmed OT; controls had codes for ovarian mass or cyst and surgically confirmed absence of OT. Preoperative transabdominal ultrasounds were analyzed by 3 radiologists blinded to final diagnosis. We used χ2, Fisher[s exact, and Student's t tests for statistical comparisons. RESULTS: From 2016 to 2017, 32 patients presented with acute abdominal pain or symptoms concerning for ovarian mass requiring ultrasound imaging and subsequent diagnostic laparoscopy; 24 (75.0%) had confirmed OT by laparoscopy, and 8 (25.0%) did not. The mean age in both groups was similar (7.3 ± 2.9 years). Preoperative sonographic variables significantly associated with OT included presence of a simple cyst (20.8% vs 12.5%), ovarian heterogeneity (100% vs 12.5%), presence of peripheralized follicles (70.8% vs 0%), and asymmetry of color Doppler (75.0% vs 37.5%; all P < .05). Presence of free fluid, arterial color Doppler, and a whirlpool sign were not predictive of OT. CONCLUSION: In premenarchal patients, although certain variables on transabdominal sonography predicted surgically confirmed OT, only the presence of peripheralized follicles was unique to girls with OT. The decision to proceed with diagnostic laparoscopy for suspected OT can be aided by these specific sonographic findings but should ultimately be based on high clinical suspicion.

In utero torsion of an accessory hepatic lobe mimicking a congenital tumor.

Accessory hepatic lobes are rare anatomic variants connected to the liver by a fibrous stalk or parenchymal attachments. They are usually detected incidentally, but torsion is a rare complication. Here, we report torsion of an accessory hepatic lobe occurring in utero with a focus on the MRI findings. The lesion mimicked a congenital tumor, and we provide potential clues that may have narrowed the differential diagnosis prior to surgical exploration.

The "Double Ovary" Sign: A Unique Sonographic Observation in Isolated Fallopian Tube Torsion.

Isolated fallopian tube torsion (IFTT) is a rare subset of adnexal torsion. Timely diagnosis of IFTT is essential for preservation of the fallopian tube. However, a pre-operative diagnosis is challenging due to nonspecific symptoms and findings on physical exam. In addition, ultrasound (US) is typically the initial imaging modality in this setting and adnexal torsion may not be considered when normal ovaries are seen. In this small case series, we introduce the "double ovary" sign, a unique observation on US characterized by two adjacent structures: the ovary and the twisted fallopian tube giving rise to an ovary-like, cystic structure. We present three cases in which IFTT was diagnosed preoperatively.

Wandering liver, spleen, and kidney: what the radiologist needs to know.

The wandering spleen, wandering liver, and wandering kidney are rare diagnoses that can be asymptomatic or are associated with nonspecific symptoms, making the clinical diagnosis elusive. In addition, given the small number of cases, these conditions are not well understood. Major complications of wandering spleen result from torsion of the vascular pedicle with resultant ischemia, physiologic dysfunction, and/or infarction. Wandering liver is commonly associated with bowel obstruction, particularly colonic volvulus, with very rare reports of hepatic ischemia or infarct. Wandering kidneys are not commonly associated with serious complications. In many cases, the wandering spleen, liver or kidney can be found in their anatomic position on static imaging and are only diagnosed during ultrasound or with serial radiographic or cross-sectional imaging with different patient positioning, or with prior studies demonstrating different locations of the involved organ. Treatment approaches for uncomplicated wandering spleen, liver, or kidney include watchful waiting and splenopexy, hepatopexy, or nephropexy, respectively. Complicated wandering spleens are treated with splenectomy. Given the variable clinical presentation of these conditions, imaging plays a pivotal role in diagnosing these rare and often incidentally discovered phenomena.

Ultra-low-dose CT is feasible for torsion measurement of the lower limb in patients with metal implants.

OBJECTIVES: Patients who need torsion measurement of the lower limb often have metal implants hindering e.g. MRI. A new ultra-low-dose (ULD-)CT protocol might be feasible for torsion measurement at cost of relatively low radiation exposure. METHODS: We retrospectively included all patients with clinically indicated torsion measurement in the period July 2019 to June 2021 and metal implants in the scanning field. The ULD-CT protocol comprised automated tube current time product and automated tube voltage with reference settings of 100kV/20mAs (hip), 80kV/20mAs (knee) and 80kV/10mAs (ankle). Femoral neck anteversion, tibial, intra-articular knee and overall leg torsion measurements were performed by two radiologists independently. Diagnostic confidence regarding the delineation of the relevant cortical bone was rated on a 5-point Likert scale (1 = non-diagnostic, 5 = excellent). RESULTS: 102 consecutive patients could be included (BMI 27.38 ± 5.85) with 154 metal implants. Median total dose length product of the ULD-CT-torsion measurement was 16.5mGycm [11-39]. Both readers showed high agreement with a maximum torsional difference of 4.1°. Diagnostic confidence was rated best (5/5) in 92.2% (reader 1) and 93.1% (reader 2) with a worst rating of 3/5. CONCLUSION: The new ULD-CT protocol is feasible for torsion measurement of the lower limb - even in patients with metal implants. ADVANCES IN KNOWLEDGE: Metal implants are not an obstacle for ULD-CT torsion measurements of the lower limb.

Diagnostic accuracy of ultrasound signs for detecting adnexal torsion: systematic review and meta-analysis.

OBJECTIVE: To evaluate the diagnostic accuracy of different ultrasound signs for diagnosing adnexal torsion, using surgery as the reference standard. METHODS: This was a systematic review and meta-analysis of studies published between January 1990 and November 2021 evaluating ovarian edema, adnexal mass, ovarian Doppler flow findings, the whirlpool sign and pelvic fluid as ultrasound signs (index tests) for detecting adnexal torsion, using surgical findings as the reference standard. The search for studies was performed in PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov and Web of Science databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to evaluate the quality of the studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated separately, and the post-test probability of adnexal torsion following a positive or negative test was also determined. RESULTS: The search identified 1267 citations after excluding duplicates. Eighteen studies were ultimately included in the qualitative and quantitative syntheses. Eight studies (809 patients) analyzed the presence of ovarian edema, eight studies (1044 patients) analyzed the presence of an adnexal mass, 14 studies (1742 patients) analyzed ovarian Doppler flow, six studies (545 patients) analyzed the whirlpool sign and seven studies (981 patients) analyzed the presence of pelvic fluid as ultrasound signs of adnexal torsion. Overall, the quality of most studies was considered to be moderate or good. However, there was a high risk of bias in the patient-selection and index-text domains (with the exception of the whirlpool sign) in a significant proportion of studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios of each ultrasound sign were 58%, 86%, 4.0 and 0.49 for ovarian edema, 69%, 46%, 1.3 and 0.67 for adnexal mass, 65%, 91%, 7.6 and 0.38 for the whirlpool sign, 53%, 95%, 11.0 and 0.49 for ovarian Doppler findings and 55%, 69%, 1.7 and 0.66 for pelvic fluid. Heterogeneity was high for all analyses. CONCLUSIONS: The presence of an adnexal mass or pelvic fluid have poor diagnostic accuracy as ultrasound signs of adnexal torsion, while the presence of ovarian edema, the whirlpool sign and decreased or absent ovarian Doppler flow have good specificity but moderate sensitivity for detecting adnexal torsion. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.