posterior horn
Recently Published Documents


TOTAL DOCUMENTS

215
(FIVE YEARS 62)

H-INDEX

27
(FIVE YEARS 3)

2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Ying Pu ◽  
Zhu Lei ◽  
Ding Wenge ◽  
Xu Yue ◽  
Jiang Xiaowei ◽  
...  

Abstract Background There is a great deal of controversy on whether routine MRI examination is needed for fresh fractures while the vast majority of patients with tibial plateau fractures (TPFs) receive preoperative X-ray and CT examinations. The purpose of the study was to analyze the exact correlation between CT images of lateral plateau and lateral meniscus injuries in Schatzker II TPFs. Methods A total of 296 patients with Schatzker II TPFs from August 2012 to January 2021 in two trauma centers were enrolled for the analysis. According to the actual situation during open reduction internal fixation (ORIF) and knee arthroscopic surgery, patients were divided into meniscus injury (including rupture, incarceration, etc.) and non-meniscus injury groups. The values of both lateral plateau depression (LPD) and lateral plateau widening (LPW) of lateral tibial plateau on CT images were measured, and their correlation with lateral meniscus injury was then analyzed. The relevant receiver operating characteristic (ROC) curve was drawn to evaluate the optimal cut-off point of the two indicators which could predict meniscus injury. Results The intra- and inter-observer reliabilities of LPD and LPW were acceptable (intraclass correlation coefficient (ICC) > 0.8). The average LPD was 13.2 ± 3.2 mm while the average value of the group without meniscus injury was 9.4 ± 3.2 mm. The difference between the two groups was statistically significant (P < 0.05). The average LPW was 8.0 ± 1.4 mm and 6.8 ± 1.6 mm in meniscus injury and non-meniscus injury groups with a significant difference (P < 0.05). The optimal predictive cut-off value of LPD and LPW was 7.9 mm (sensitivity-95.0%, specificity-58.8%, area under the curve (AUC-0.818) and 7.5 mm (sensitivity-70.0%, specificity - 70.6%, AUC - 0.724), respectively. The meniscus injury group mainly showed injuries involving the mid-body and posterior horn of lateral meniscus (98.1%, 157/160). Conclusions The mid-body and posterior horn of lateral meniscus injury is more likely to occur in patients with Schatzker II TPFs when LPD > 7.9 mm and/or LPW > 7.5 mm on CT. These findings will definitely provide guidance for orthopedic surgeons in treating such injuries. During the operation, more attention is required be paid to the treatment of the meniscus and the possible fracture reduction difficulties and poor alignment caused by meniscus rupture and incarceration should be fully considered in order to achieve better surgical results.


Author(s):  
S. E. Baibakov ◽  
N. S. Bakhareva ◽  
E. K. Gordeeva ◽  
M. V. Yuzhakov ◽  
D. A. Khromov ◽  
...  

Relevance Investigation of the cerebrospinal fluid system of children of different ages, especially pre-school and school periods of childhood, becomes essential, since the further development of the brain and its proper functioning depends on the way it functions. Considering the MRI indications of the elements of the cerebrospinal fluid system of children is important for the development of neurology and neurosurgery, it is necessary to consider gender differences in the brain size and structure.Objective To study the sex differences in the structure of the cerebrospinal fluid system in seven-year-old children.Material and Methods For the study, archival data on the sizes of the lateral ventricles of the brain of 120 children aged 7 (60 boys and 60 girls) were involved, in particular: 1) the length of the anterior horn; 2) the width of the anterior horn; 3) the length of the central part; 4) the width of the central part; 5) the length of the posterior horn; 6) the width of the posterior horn; 7) the length of the lower horn; 8) the anteroposterior size; 9) the distance between the anterior horns; 10) the distance between the posterior horns; 11) the length of the third ventricle; 12) the height of the third ventricle; 13) the length of the aqueduct; 14) the length of the fourth ventricle; 15) the height of the fourth ventricle. The studies were carried out using the method of magnetic resonance imaging. Quantitative indicators were assessed for compliance with the normal distribution using the KolmogorovSmirnov test. The accumulation, correction, systematization of the initial information were carried out in Microsoft Excel 2016. Statistical analysis was carried out using the Statistica 10.0 software (StatSoft Inc., USA). The results were considered statistically significant at p < 0.05.Results The data obtained in the study of the cerebrospinal fluid system in children during their pre-school period of childhood are indicators of the norm and can be used for diagnostic studies in the departments of radiation diagnostics. The bilateral asymmetry of the lateral ventricles of the brain in pre-school children, discovered during the work, is of crucial clinical significance. The morphometric indicators of the elements of the cerebrospinal fluid system should be considered by specialists in the study of brain neuroplasticity.Conclusion Analysis of the obtained in vivo encephalometric data indicates the presence of sexual variability of the brain and parameters of the structures of the cerebrospinal fluid.


Author(s):  
Alexander Tack ◽  
Alexey Shestakov ◽  
David Lüdke ◽  
Stefan Zachow

We present a novel and computationally efficient method for the detection of meniscal tears in Magnetic Resonance Imaging (MRI) data. Our method is based on a Convolutional Neural Network (CNN) that operates on complete 3D MRI scans. Our approach detects the presence of meniscal tears in three anatomical sub-regions (anterior horn, body, posterior horn) for both the Medial Meniscus (MM) and the Lateral Meniscus (LM) individually. For optimal performance of our method, we investigate how to preprocess the MRI data and how to train the CNN such that only relevant information within a Region of Interest (RoI) of the data volume is taken into account for meniscal tear detection. We propose meniscal tear detection combined with a bounding box regressor in a multi-task deep learning framework to let the CNN implicitly consider the corresponding RoIs of the menisci. We evaluate the accuracy of our CNN-based meniscal tear detection approach on 2,399 Double Echo Steady-State (DESS) MRI scans from the Osteoarthritis Initiative database. In addition, to show that our method is capable of generalizing to other MRI sequences, we also adapt our model to Intermediate-Weighted Turbo Spin-Echo (IW TSE) MRI scans. To judge the quality of our approaches, Receiver Operating Characteristic (ROC) curves and Area Under the Curve (AUC) values are evaluated for both MRI sequences. For the detection of tears in DESS MRI, our method reaches AUC values of 0.94, 0.93, 0.93 (anterior horn, body, posterior horn) in MM and 0.96, 0.94, 0.91 in LM. For the detection of tears in IW TSE MRI data, our method yields AUC values of 0.84, 0.88, 0.86 in MM and 0.95, 0.91, 0.90 in LM. In conclusion, the presented method achieves high accuracy for detecting meniscal tears in both DESS and IW TSE MRI data. Furthermore, our method can be easily trained and applied to other MRI sequences.


The Knee ◽  
2021 ◽  
Vol 33 ◽  
pp. 234-242
Author(s):  
Nicola Oehler ◽  
Andreas Foerg ◽  
Maximilian Haenle ◽  
Fabian Blanke ◽  
Stephan Vogt

Author(s):  
Christophe Jacquet ◽  
Caroline Mouton ◽  
Amanda Magosch ◽  
George A. Komnos ◽  
Jacques Menetrey ◽  
...  

Abstract Purpose Anterior cruciate ligament (ACL) injuries often lead to associated injuries of the posterior horn of the lateral meniscus (PHLM). Arthroscopic, assessment of PHLM instability may be difficult in the absence of a visible meniscus damage. The main objective of this prospective multi-center study was to compare the ability of the probing and aspiration tests to identify PHLM instability in a population of patients undergoing ACL reconstruction (ACLR) and a control group of patients with an intact ACL undergoing knee arthroscopy. Methods A prospective case–control analysis was performed in three sports medicine centers. One-hundred and three consecutive patients operated for a primary isolated ACLR without structural lateral meniscus damage other than a root tear were included. They were compared to a control group of 29 consecutive patients who had a knee arthroscopy with an intact ACL and no structural lateral meniscus lesion. The probing and aspiration tests were consecutively executed according to previously published methods. Results In the control group, no lateral meniscus lesions were visualized during arthroscopy, and both probing and aspiration tests were negative in all patients. In the group of ACL-injured patients, a Forkel type I–III posterolateral meniscus root tear (PLMRT) was found in 12 patients (12%). In this subgroup, the probing test was positive in 4/12 patients (33%) and the aspiration test in 5 additional patients (75%). In 15 patients (15%), an elongation of the posterior root of the lateral meniscus (defined as type IV PLMRT as an addendum to the Forkel classification) could be observed during arthroscopy. In this subgroup, only 1 patient displayed a PHLM instability with the probing test (7%), whereas the aspiration test was positive in 13/15 patients (87%). In the remaining 76 patients (74%), no structural lesion of the PHLM could be identified. Nevertheless, an instability of the PHLM could be identified in 8 of them (11%) with the probing test, and the aspiration test was positive in 2 additional knees (13%) of this apparently normal subgroup. Altogether, in the entire ACL injury cohort, a positive probing test was observed in 13/103 patients (13%) and a positive aspiration test in 32/103 knees (31%) (p < 0.01). Conclusion Careful observation and examination of the PHLM with the aspiration test revealed a substantial amount of previously undiagnosed lateral meniscus instabilities in ACL-injured knees. The prevalence of PHLM instability as evaluated by the aspiration test was high (31%). The aspiration test was superior to the probing test in detecting an instability of the PHLM in a population of ACL-injured patients. Level of evidence II.


2021 ◽  
Vol 22 (22) ◽  
pp. 12465
Author(s):  
Barbara Canciani ◽  
Valentina Rafaela Herrera Millar ◽  
Margherita Pallaoro ◽  
Lucia Aidos ◽  
Federica Cirillo ◽  
...  

Menisci play an essential role in shock absorption, joint stability, load resistance and its transmission thanks to their conformation. Adult menisci can be divided in three zones based on the vascularization: an avascular inner zone with no blood supply, a fully vascularized outer zone, and an intermediate zone. This organization, in addition to the incomplete knowledge about meniscal biology, composition, and gene expression, makes meniscal regeneration still one of the major challenges both in orthopedics and in tissue engineering. To overcome this issue, we aimed to investigate the role of hypoxia in the differentiation of the three anatomical areas of newborn piglet menisci (anterior horn (A), central body (C), and posterior horn (P)) and its effects on vascular factors. After sample collection, menisci were divided in A, C, P, and they were cultured in vitro under hypoxic (1% O2) and normoxic (21% O2) conditions at four different experimental time points (T0 = day of explant; T7 = day 7; T10 = day 10; T14 = day 14); samples were then evaluated through immune, histological, and molecular analyses, cell morpho-functional characteristics; with particular focus on matrix composition and expression of vascular factors. It was observed that hypoxia retained the initial phenotype of cells and induced extracellular matrix production resembling a mature tissue. Hypoxia also modulated the expression of angiogenic factors, especially in the early phase of the study. Thus, we observed that hypoxia contributes to the fibro-chondrogenic differentiation with the involvement of angiogenic factors, especially in the posterior horn, which corresponds to the predominant weight-bearing portion.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Atul K. Taneja ◽  
Frederico C. Miranda ◽  
Laercio A. Rosemberg ◽  
Durval C. B. Santos

AbstractThe purpose of this review is to describe the anatomy and lesions affecting the peripheral portion of posterior horn of medial menisci (ramp lesions), along with illustrations and MRI cases. We will correlate imaging features with arthroscopic classification of ramp lesions. Also, postoperative and chronic changes related to meniscocapsular tears will be presented, as well as biomechanical consequences and treatment approach.


2021 ◽  
pp. 036354652110335
Author(s):  
Kazuya Nishino ◽  
Yusuke Hashimoto ◽  
Syuko Tsumoto ◽  
Shinya Yamasaki ◽  
Hiroaki Nakamura

Background: Arthroscopic reshaping surgery is the first treatment option for a symptomatic discoid lateral meniscus (DLM) to preserve the peripheral rim. However, the degree of postoperative morphological change in the residual meniscus is unclear. Purpose/Hypothesis: The purpose of this study was to measure the meniscus after reshaping surgery for a DLM, to verify when the morphological change occurred, and to examine the related risk factors. The hypothesis was that the residual meniscal width would decrease throughout the postoperative course. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively reviewed the medical records of patients who underwent reshaping surgery for a symptomatic DLM and had undergone follow-up for ≥2 years. Magnetic resonance imaging (MRI) was routinely performed preoperatively and at 3, 6, 12, and 24 months postoperatively, and the width, height, and extrusion of the residual meniscus were measured. According to the width of the midbody on final MRI scans, we compared the preoperative and postoperative data for the preserved group (≥5 mm) and decreased group (<5 mm). The associated risk factors for a decreased meniscal width (<5 mm) of the midbody were analyzed on final MRI scans. Results: We included 61 knees of 54 patients in this study. The mean age at the time of surgery was 11.7 years. The intraobserver and interobserver reliabilities of the midbody width were 0.937 and 0.921, respectively. The width of the anterior horn, midbody, and posterior horn decreased significantly from 3 to 24 months after surgery (from 9.1 to 8.6 mm [ P < .001], from 7.5 to 6.1 mm [ P < .001], and from 9.5 to 8.9 mm [ P = .001], respectively). Meniscal extrusion of the midbody did not change significantly (from 1.2 to 1.5 mm; P = .062). Overall, 46 knees (n = 20/32 in the preserved group and n = 26/29 in the decreased group) had longitudinal tears that required meniscal repair. Clinical outcomes did not differ significantly between the 2 groups. Multivariate logistic analysis showed that intrameniscal degeneration (odds ratio, 4.36; P = .023) significantly increased the risk of a decreased meniscal width. Conclusion: The width of the anterior horn, midbody, and posterior horn decreased significantly from 3 to 24 months after surgery. In particular, the average decrease rate of the midbody was 19%. No clinical difference was seen in patients with a decreased width and height or with peripheral extrusion. Increased intrameniscal signals on preoperative MRI scans were associated with an increased risk of a decreased meniscal width. Surgeons should consider this result to determine the amount of resection.


Author(s):  
Takaki Sanada ◽  
Hiroshi Iwaso ◽  
Eisaburo Honda ◽  
Hiroki Yoshitomi ◽  
Miyu Inagawa

2021 ◽  
Author(s):  
Pu Ying ◽  
Lei Zhu ◽  
Wenge Ding ◽  
Yue Xu ◽  
Xiaowei Jiang ◽  
...  

Abstract Background: There is a great deal of controversy on whether routine MRI examination is needed for fresh fractures while the vast majority of patients with tibial plateau fractures receive preoperative X-ray and CT examinations. The purpose of the study was to analyze the exact correlation between CT images of lateral plateau and lateral meniscus injuries in Schatzker II tibial plateau fractures. Methods: Two hundred and ninety-six Schatzker II tibial plateau fracture patients from August 2012 to January 2021 in two trauma centers were enrolled for the analysis. According to the actual situation during open reduction internal fixation (ORIF) and knee arthroscopic surgery, patients were divided into meniscus injury (including rupture, incarceration, etc.) and non-meniscus injury groups. By measuring the value of both lateral plateau depression (LPD) and lateral plateau widening (LPW) of lateral tibial plateau on the coronary CT images, the correlation of which and lateral meniscus injury was analyzed. Meanwhile, the relevant receiver operating characteristic (ROC) curve was drawn to evaluate the optimal operating point of these two indicators which could predict meniscus injury. Results: Meniscus injury group mainly showed injuries involving the mid-body and posterior horn of the meniscus (98.1%, 157/160). The average LPD was 13.2 ± 3.2 mm, while the average value of the group without meniscus injury was 9.4 ± 3.2 mm. The difference was statistically significant (P < 0.05). The average LPW was 8.0 ± 1.4 mm and 6.8 ± 1.6 mm in two groups with a significant difference (P < 0.05). The optimal operating point of LPD and LPW was 7.9 mm (sensitivity-95.0%, specificity-58.8%, area under the curve (AUC-0.818) and 7.5 mm (sensitivity-70.0%, specificity-70.6%, AUC-0.724), respectively. Conclusions: The mid-body and posterior horn of lateral meniscus injury is more likely to occur in patients who had Schatzker II tibial plateau fractures when LPD > 7.9 mm and/or LPW > 7.5 mm on CT manifestations and these findings will definitely provide guidance for orthopedic surgeons in treating such injuries. During the operation, more attention should be paid to the treatment of the meniscus and full consideration is needed be taken to situations such as meniscus rupture, incarceration and other possible fracture reduction difficulties, poor vertical line, etc., in order to achieve better surgical results.


Sign in / Sign up

Export Citation Format

Share Document