RB Particle Filter Time Synchronization Algorithm Based on the DPM Model.

PubMed

Guo, Chunsheng; Shen, Jia; Sun, Yao; Ying, Na

2015-09-03

Time synchronization is essential for node localization, target tracking, data fusion, and various other Wireless Sensor Network (WSN) applications. To improve the estimation accuracy of continuous clock offset and skew of mobile nodes in WSNs, we propose a novel time synchronization algorithm, the Rao-Blackwellised (RB) particle filter time synchronization algorithm based on the Dirichlet process mixture (DPM) model. In a state-space equation with a linear substructure, state variables are divided into linear and non-linear variables by the RB particle filter algorithm. These two variables can be estimated using Kalman filter and particle filter, respectively, which improves the computational efficiency more so than if only the particle filter was used. In addition, the DPM model is used to describe the distribution of non-deterministic delays and to automatically adjust the number of Gaussian mixture model components based on the observational data. This improves the estimation accuracy of clock offset and skew, which allows achieving the time synchronization. The time synchronization performance of this algorithm is also validated by computer simulations and experimental measurements. The results show that the proposed algorithm has a higher time synchronization precision than traditional time synchronization algorithms.

The Saccharomyces cerevisiae DPM1 gene encoding dolichol-phosphate-mannose synthase is able to complement a glycosylation-defective mammalian cell line.

PubMed Central

Beck, P J; Orlean, P; Albright, C; Robbins, P W; Gething, M J; Sambrook, J F

1990-01-01

The Saccharomyces cerevisiae DPM1 gene product, dolichol-phosphate-mannose (Dol-P-Man) synthase, is involved in the coupled processes of synthesis and membrane translocation of Dol-P-Man. Dol-P-Man is the lipid-linked sugar donor of the last four mannose residues that are added to the core oligosaccharide transferred to protein during N-linked glycosylation in the endoplasmic reticulum. We present evidence that the S. cerevisiae gene DPM1, when stably transfected into a mutant Chinese hamster ovary cell line, B4-2-1, is able to correct the glycosylation defect of the cells. Evidence for complementation includes (i) fluorescence-activated cell sorter analysis of differential lectin binding to cell surface glycoproteins, (ii) restoration of Dol-P-Man synthase enzymatic activity in crude cell lysates, (iii) isolation and high-performance liquid chromatography fractionation of the lipid-linked oligosaccharides synthesized in the transfected and control cell lines, and (iv) the restoration of endoglycosidase H sensitivity to the oligosaccharides transferred to a specific glycoprotein synthesized in the DPM1 CHO transfectants. Indirect immunofluorescence with a primary antibody directed against the DPM1 protein shows a reticular staining pattern of protein localization in transfected hamster and monkey cell lines. Images PMID:2201896

Extended System Operations Studies for Automated Guideway Transit Systems : Plan for Task 5--DPM Failure Management

DOT National Transportation Integrated Search

1981-06-01

The purpose of Task 5 in the Extended System Operations Studies Project, DPM Failure Management, is to enhance the capabilities of the Downtown People Mover Simulation (DPMS) and the Discrete Event Simulation Model (DESM) by increasing the failure mo...

Application of microwave energy in the control of DPM, oxides of nitrogen and VOC emissions

NASA Astrophysics Data System (ADS)

Pallavkar, Sameer M.

The emissions of DPM (diesel particulate matter), NOx (oxides of nitrogen), and toxic VOCs (volatile organic compounds) from diesel engine exhaust gases and other sources such as chemical process industry and manufacturing industry have been a great environmental and health concern. Most control technologies for these emissions require elevated temperatures. The use of microwave energy as a source of heat energy, however, has not been fully explored. In this study, the microwave energy was used as the energy source in three separate emission control processes, namely, the regeneration of diesel particulate filter (DPF) for DPM control, the NOx reduction using a platinum catalyst, and the VOC destruction involving a ceramic based material. The study has demonstrated that microwave heating is an effective method in providing heat for the studied processes. The control efficiencies associated with the microwave-assisted processes have been observed to be high and acceptable. Further research, however, is required for the commercial use of these technologies.

Many-integrated core (MIC) technology for accelerating Monte Carlo simulation of radiation transport: A study based on the code DPM

NASA Astrophysics Data System (ADS)

Rodriguez, M.; Brualla, L.

2018-04-01

Monte Carlo simulation of radiation transport is computationally demanding to obtain reasonably low statistical uncertainties of the estimated quantities. Therefore, it can benefit in a large extent from high-performance computing. This work is aimed at assessing the performance of the first generation of the many-integrated core architecture (MIC) Xeon Phi coprocessor with respect to that of a CPU consisting of a double 12-core Xeon processor in Monte Carlo simulation of coupled electron-photonshowers. The comparison was made twofold, first, through a suite of basic tests including parallel versions of the random number generators Mersenne Twister and a modified implementation of RANECU. These tests were addressed to establish a baseline comparison between both devices. Secondly, through the p DPM code developed in this work. p DPM is a parallel version of the Dose Planning Method (DPM) program for fast Monte Carlo simulation of radiation transport in voxelized geometries. A variety of techniques addressed to obtain a large scalability on the Xeon Phi were implemented in p DPM. Maximum scalabilities of 84 . 2 × and 107 . 5 × were obtained in the Xeon Phi for simulations of electron and photon beams, respectively. Nevertheless, in none of the tests involving radiation transport the Xeon Phi performed better than the CPU. The disadvantage of the Xeon Phi with respect to the CPU owes to the low performance of the single core of the former. A single core of the Xeon Phi was more than 10 times less efficient than a single core of the CPU for all radiation transport simulations.

DPM, Payload Commander Kathy Thornton and Commander Ken Bowersox in Spacelab

NASA Image and Video Library

1995-11-05

STS073-229-014 (20 October - 5 November 1995) --- Astronauts Kathryn C. Thornton, STS-73 payload commander, and Kenneth D. Bowersox, mission commander, observe a liquid drop's activity at the Drop Physics Module (DPM) in the science module aboard the Earth-orbiting Space Shuttle Columbia. The drop is partially visible at the center of the left edge of the frame. The two were joined by three other NASA astronauts and two guest researchers for almost 16-days of in-orbit research in support of the U.S. Microgravity Laboratory (USML-2) mission.

Measurement of Area and Personal Breathing Zone Concentrations of Diesel Particulate Matter (DPM) during Oil and Gas Extraction Operations, including Hydraulic Fracturing

PubMed Central

Esswein, Eric J.; Alexander-Scott, Marissa; Snawder, John; Breitenstein, Michael

2018-01-01

Diesel engines serve many purposes in modern oil and gas extraction activities. Diesel particulate matter (DPM) emitted from diesel engines is a complex aerosol that may cause adverse health effects depending on exposure dose and duration. This study reports on personal breathing zone (PBZ) and area measurements for DPM (expressed as elemental carbon) during oil and gas extraction operations including drilling, completions (which includes hydraulic fracturing) and servicing work. Researchers at the National Institute for Occupational Safety and Health (NIOSH) collected 104 full-shift air samples (49 PBZ and 55 area) in Colorado, North Dakota, Texas, and New Mexico during a four year period from 2008-2012 The arithmetic mean (AM) of the full shift TWA PBZ samples was 10 μg/m3; measurements ranged from 0.1 to 52 μg/m3. The geometric mean (GM) for the PBZ samples was 7 μg/m3. The AM of the TWA area measurements was 17 μg/m3 and ranged from 0.1 to 68 μg/m3. The GM for the area measurements was 9.5 μg/m3. Differences between the GMs of the PBZ samples and area samples were not statistically different (P>0.05). Neither the Occupational Safety and Health Administration (OSHA), NIOSH, nor the American Conference of Governmental Industrial Hygienists (ACGIH) have established occupational exposure limits (OEL) for DPM. However, the State of California, Department of Health Services lists a time-weighted average (TWA) OEL for DPM as elemental carbon (EC) exposure of 20 μg/m3. Five of 49 (10.2%) PBZ TWA measurements exceeded the 20 μg/m3 EC criterion. These measurements were collected on Sandmover and Transfer Belt (T-belt) Operators, Blender and Chemical Truck Operators, and Water Transfer Operators during hydraulic fracturing operations. Recommendations to minimize DPM exposures include elimination (locating diesel-driven pumps away from well sites), substitution, (use of alternative fuels), engineering controls using advanced emissions controls technologies

Measurement of area and personal breathing zone concentrations of diesel particulate matter (DPM) during oil and gas extraction operations, including hydraulic fracturing.

PubMed

Esswein, Eric J; Alexander-Scott, Marissa; Snawder, John; Breitenstein, Michael

2018-01-01

Diesel engines serve many purposes in modern oil and gas extraction activities. Diesel particulate matter (DPM) emitted from diesel engines is a complex aerosol that may cause adverse health effects depending on exposure dose and duration. This study reports on personal breathing zone (PBZ) and area measurements for DPM (expressed as elemental carbon) during oil and gas extraction operations including drilling, completions (which includes hydraulic fracturing), and servicing work. Researchers at the National Institute for Occupational Safety and Health (NIOSH) collected 104 full-shift air samples (49 PBZ and 55 area) in Colorado, North Dakota, Texas, and New Mexico during a four-year period from 2008-2012. The arithmetic mean (AM) of the full shift TWA PBZ samples was 10 µg/m 3 ; measurements ranged from 0.1-52 µg/m 3 . The geometric mean (GM) for the PBZ samples was 7 µg/m 3 . The AM of the TWA area measurements was 17 µg/m 3 and ranged from 0.1-68 µg/m 3 . The GM for the area measurements was 9.5 µg/m 3 . Differences between the GMs of the PBZ samples and area samples were not statistically different (P > 0.05). Neither the Occupational Safety and Health Administration (OSHA), NIOSH, nor the American Conference of Governmental Industrial Hygienists (ACGIH) have established occupational exposure limits (OEL) for DPM. However, the State of California, Department of Health Services lists a time-weighted average (TWA) OEL for DPM as elemental carbon (EC) exposure of 20 µg/m 3 . Five of 49 (10.2%) PBZ TWA measurements exceeded the 20 µg/m 3 EC criterion. These measurements were collected on Sandmover and Transfer Belt (T-belt) Operators, Blender and Chemical Truck Operators, and Water Transfer Operators during hydraulic fracturing operations. Recommendations to minimize DPM exposures include elimination (locating diesel-driven pumps away from well sites), substitution, (use of alternative fuels), engineering controls using advanced emission control

DPM and Glovebox, Payload Commander Kathy Thornton and Payload Specialist Albert Sacco in Spacelab

NASA Image and Video Library

1995-10-21

STS073-E-5003 (23 Oct. 1995) --- Astronaut Kathryn C. Thornton, STS-73 payload commander, works at the Drop Physics Module (DPM) on the portside of the science module aboard the Space Shuttle Columbia in Earth orbit. Payload specialist Albert Sacco Jr. conducts an experiment at the Glovebox. This frame was exposed with the color Electronic Still Camera (ESC) assigned to the 16-day United States Microgravity Laboratory (USML-2) mission.

Ipsilateral Medial and Lateral Discoid Meniscus with Medial Meniscus Tear

PubMed Central

Shimozaki, Kengo; Nakase, Junsuke; Ohashi, Yoshinori; Numata, Hitoaki; Oshima, Takeshi; Takata, Yasushi; Tsuchiya, Hiroyuki

2016-01-01

Introduction: Discoid meniscus is a well-documented knee pathology, and there are many cases of medial or lateral discoid meniscus reported in the literature. However, ipsilateral concurrent medial and lateral discoid meniscus is very rare, and only a few cases have been reported. Herein, we report a case of concurrent medial and lateral discoid meniscus. Case Report: A 27-year-old Japanese man complained of pain on medial joint space in his right knee that was diagnosed as a complete medial and lateral discoid meniscus. In magnetic resonance imaging, although the lateral discoid meniscus had no tear, the medial discoid meniscus had a horizontal tear. Arthroscopic examination of his right knee similarly revealed that the medial discoid meniscus had a horizontal tear. In addition, the discoid medial meniscus also had an anomalous insertion to the anterior cruciate ligament, and there was also mild fibrillation of the medial tibial cartilage surface. We performed arthroscopic partial meniscectomy for the torn medial discoid meniscus but not for the asymptomatic lateral discoid meniscus. The latest follow-up at 18 months indicated satisfactory results. Conclusion: We report a rare case of ipsilateral medial and lateral discoid meniscus with medial meniscus tear. The medial discoid meniscus with tear was treated with partial meniscectomy, whereas the lateral discoid meniscus without tear was only followed up. PMID:28164045

Evaluation of the isometry of different points of the patella and femur for medial patellofemoral ligament reconstruction.

PubMed

Gobbi, Riccardo Gomes; Pereira, César Augusto Martins; Sadigursky, David; Demange, Marco Kawamura; Tírico, Luis Eduardo Passarelli; Pécora, José Ricardo; Camanho, Gilberto Luis

2016-10-01

The location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points. Ten cadaver knees were attached to an apparatus that simulated an active range of motion of 120°, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5mm anterior (5) and posterior (7) to the epicondyle, points 5mm anterior to point 5 (4) and 5mm posterior to point 7 (8), and points 5mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15° intervals. The pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location. Surgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Medial elbow pain

PubMed Central

Barco, Raul; Antuña, Samuel A.

2017-01-01

Medial elbow pain is uncommon when compared with lateral elbow pain. Medial epicondylitis is an uncommon diagnosis and can be confused with other sources of pain. Overhead throwers and workers lifting heavy objects are at increased risk of medial elbow pain. Differential diagnosis includes ulnar nerve disorders, cervical radiculopathy, injured ulnar collateral ligament, altered distal triceps anatomy or joint disorders. Children with medial elbow pain have to be assessed for ‘Little League elbow’ and fractures of the medial epicondyle following a traumatic event. This paper is primarily focused on the differential diagnosis of medial elbow pain with basic recommendations on treatment strategies. Cite this article: EFORT Open Rev 2017;2:362-371. DOI: 10.1302/2058-5241.2.160006 PMID:28932488

Complex Medial Meniscus Tears Are Associated With a Biconcave Medial Tibial Plateau.

PubMed

Barber, F Alan; Getelman, Mark H; Berry, Kathy L

2017-04-01

To determine whether an association exists between a biconcave medial tibial plateau and complex medial meniscus tears. A consecutive series of stable knees undergoing arthroscopy were evaluated retrospectively with the use of preoperative magnetic resonance imaging (MRI), radiographs, and arthroscopy documented by intraoperative videos. Investigators independently performed blinded reviews of the MRI or videos. Based on the arthroscopy findings, medial tibial plateaus were classified as either biconcave or not biconcave. A transverse coronal plane ridge, separating the front of the tibial plateau from the back near the inner margin of the posterior body of the medial meniscus, was defined as biconcave. The medial plateau slope was calculated with MRI sagittal views. General demographic information, body mass index, and arthroscopically confirmed knee pathology were recorded. A total of 179 consecutive knees were studied from July 2014 through August 2015; 49 (27.2%) biconcave medial tibial plateaus and 130 (72.8%) controls were identified at arthroscopy. Complex medial meniscus tears were found in 103. Patients with a biconcave medial tibial plateau were found to have more complex medial meniscus tears (69.4%) than those without a biconcavity (53.1%) (P = .049) despite having lower body mass index (P = .020). No difference in medial tibial plateau slope was observed for biconcavities involving both cartilage and bone, bone only, or an indeterminate group (P = .47). Biconcave medial tibial plateaus were present in 27.4% of a consecutive series of patients undergoing knee arthroscopy. A biconcave medial tibial plateau was more frequently associated with a complex medial meniscus tear. Level III, case-control study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

Effects of MERV 16 filters and routine work practices on enclosed cabs for reducing respirable dust and DPM exposures in an underground limestone mine

PubMed Central

Noll, J.D.; Cecala, A.B.; J.A.Organiscak; Rider, J.P.

2015-01-01

An effective technique to minimize miners’ respirable dust and diesel exposure on mobile mining equipment is to place mine operators in enclosed cabs with designed filtration and pressurization systems. Many factors affect the performance of these enclosed cab systems, and one of the most significant factors is the effectiveness of the filtration system. High-efficiency particulate air (HEPA)-type filters are typically used because they are highly efficient at capturing all types and sizes of particles, including those in the submicron range such as diesel particulate matter (DPM). However, in laboratory tests, minimum efficiency reporting value (MERV) 16 filters have proven to be highly efficient for capturing DPM and respirable dust. Also, MERV 16 filters can be less restrictive to cab airflow and less expensive than HEPA filters. To verify their effectiveness in the field, MERV 16 filters were used in the enclosed cab filtration system on a face drill and roof bolting mining machine and tested at an underground limestone mine. Test results showed that DPM and respirable dust concentrations were reduced by more than 90% when the cabs were properly sealed. However, when the cab door was opened periodically throughout the shift, the reduction efficiency of the MERV 16 filters was reduced to 80% on average. PMID:26236044

The Role of Medial Temporal Lobe Regions in Incidental and Intentional Retrieval of Item and Relational Information in Aging.

PubMed

Wang, Wei-Chun; Giovanello, Kelly S

2016-06-01

Considerable neuropsychological and neuroimaging work indicates that the medial temporal lobes are critical for both item and relational memory retrieval. However, there remain outstanding issues in the literature, namely the extent to which medial temporal lobe regions are differentially recruited during incidental and intentional retrieval of item and relational information, and the extent to which aging may affect these neural substrates. The current fMRI study sought to address these questions; participants incidentally encoded word pairs embedded in sentences and incidental item and relational retrieval were assessed through speeded reading of intact, rearranged, and new word-pair sentences, while intentional item and relational retrieval were assessed through old/new associative recognition of a separate set of intact, rearranged, and new word pairs. Results indicated that, in both younger and older adults, anterior hippocampus and perirhinal cortex indexed incidental and intentional item retrieval in the same manner. In contrast, posterior hippocampus supported incidental and intentional relational retrieval in both age groups and an adjacent cluster in posterior hippocampus was recruited during both forms of relational retrieval for older, but not younger, adults. Our findings suggest that while medial temporal lobe regions do not differentiate between incidental and intentional forms of retrieval, there are distinct roles for anterior and posterior medial temporal lobe regions during retrieval of item and relational information, respectively, and further indicate that posterior regions may, under certain conditions, be over-recruited in healthy aging. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The relative contributions of MNTB and LNTB neurons to inhibition in the medial superior olive assessed through single and paired recordings

PubMed Central

Roberts, Michael T.; Seeman, Stephanie C.; Golding, Nace L.

2014-01-01

The medial superior olive (MSO) senses microsecond differences in the coincidence of binaural signals, a critical cue for detecting sound location along the azimuth. An important component of this circuit is provided by inhibitory neurons of the medial and lateral nuclei of the trapezoid body (MNTB and LNTB, respectively). While MNTB neurons are fairly well described, little is known about the physiology of LNTB neurons. Using whole cell recordings from gerbil brainstem slices, we found that LNTB and MNTB neurons have similar membrane time constants and input resistances and fire brief action potentials, but only LNTB neurons fire repetitively in response to current steps. We observed that LNTB neurons receive graded excitatory and inhibitory synaptic inputs, with at least some of the latter arriving from other LNTB neurons. To address the relative timing of inhibition to the MSO from the LNTB versus the MNTB, we examined inhibitory responses to auditory nerve stimulation using a slice preparation that retains the circuitry from the auditory nerve to the MSO intact. Despite the longer physical path length of excitatory inputs driving contralateral inhibition, inhibition from both pathways arrived with similar latency and jitter. An analysis of paired whole cell recordings between MSO and MNTB neurons revealed a short and reliable delay between the action potential peak in MNTB neurons and the onset of the resulting IPSP (0.55 ± 0.01 ms, n = 4, mean ± SEM). Reconstructions of biocytin-labeled neurons showed that MNTB axons ranged from 580 to 858 μm in length (n = 4). We conclude that while both LNTB and MNTB neurons provide similarly timed inhibition to MSO neurons, the reliability of inhibition from the LNTB at higher frequencies is more constrained relative to that from the MNTB due to differences in intrinsic properties, the strength of excitatory inputs, and the presence of feedforward inhibition. PMID:24860434

A biomechanical comparison of 2 technical variations of double-row rotator cuff fixation: the importance of medial row knots.

PubMed

Busfield, Benjamin T; Glousman, Ronald E; McGarry, Michelle H; Tibone, James E; Lee, Thay Q

2008-05-01

Previous studies have shown comparable biomechanical properties of double-row fixation versus double-row fixation with a knotless lateral row. SutureBridge is a construct that secures the cuff with medial row mattress suture anchors and knotless lateral row fixation of the medial suture ends. Recent completely knotless constructs may lead to lesser clinical outcomes if the construct properties are compromised from lack of suture knots. A completely knotless construct without medial row knots will compromise the biomechanical properties in both cyclic and failure-testing parameters. Controlled laboratory study. Six matched pairs of cadaveric shoulders were randomized to 2 groups of double row fixation with SutureBridge: group 1 with medial row knots, and group 2 without medial row knots. The specimens were placed in a materials test system at 30 degrees of abduction. Cyclic testing to 180 N at 1 mm/sec for 30 cycles was performed, followed by tensile testing to failure at 1 mm/sec. Data included cyclic and failure data from the materials test system and gap data using a video digitizing system. All data from paired specimens were compared using paired Student t tests. Group 1 had a statistically significant difference (P < .05) for gap formation for the 1st (3.47 vs 5.05 mm) and 30th cycle (4.22 vs 8.10 mm) and at yield load (5.2 vs 9.1 mm). In addition, there was a greater energy absorbed (2805 vs 1648 N-mm), yield load (233 vs 183.1 N), and ultimate load (352.9 vs 253.9 N) for group 1. The mode of failure for the majority (4/6) of group 2 was lateral row failure, whereas all group 1 specimens failed at the clamp. Although lateral row knotless fixation has been shown not to sacrifice structural integrity of this construct, the addition of a knotless medial row compromises the construct leading to greater gapping and failure at lower loads. This may raise concerns regarding recently marketed completely knotless double row constructs.

The Anatomic Midpoint of the Attachment of the Medial Patellofemoral Complex.

PubMed

Tanaka, Miho J; Voss, Andreas; Fulkerson, John P

2016-07-20

The medial patellofemoral ligament varies in attachment of its fibers to the patella and vastus intermedius tendon. Our aim was to identify and describe its anatomic midpoint. To account for the variability of the attachment site, we refer to it as the medial patellofemoral complex. Using AutoCAD software, we identified the midpoint of the medial patellofemoral complex attachment on photographs of 31 cadaveric knee dissections. The midpoint was referenced relative to the superior articular surface of the patella (P1) and was described in terms of the percentage of the patellar articular length distal to this point. A second point, at the junction of the medial border of the vastus intermedius tendon with the superior articular border of the patella, was identified (P2). The distances of the midpoint to P1 and P2 were calculated and were compared using paired t tests. Twenty-five images had appropriate quality and landmarks for digital analysis. The midpoint of the medial patellofemoral complex was located a mean (and standard deviation) of 2.3% ± 15.8% of the patellar articular length distal to the superior pole and was at or proximal to P1 in 12 knees. In all knees, the midpoint was at or proximal to P2. After exclusion of 2 knees with vastus intermedius tendon attachments only, the medial patellofemoral complex midpoint was closer to P2 (5.3% ± 8.6% of the patellar articular length) than to P1 (9.3% ± 8.5% of the patellar articular length) (p = 0.06). The midpoint of the medial patellofemoral complex was 2.3% of the articular length distal to the superior pole of the patella. Additionally, we describe an anatomic landmark at the junction of the medial border of the vastus intermedius tendon and the articular border of the patella that approximates the midpoint of this complex. Our study shows that the anatomic midpoint of the attachment of the medial patellofemoral complex is proximal to the junction of the medial vastus intermedius tendon and the articular

Outside-In Deep Medial Collateral Ligament Release During Arthroscopic Medial Meniscus Surgery.

PubMed

Todor, Adrian; Caterev, Sergiu; Nistor, Dan Viorel

2016-08-01

Arthroscopic partial medial meniscectomy is a very common orthopaedic procedure performed for symptomatic, irreparable meniscus tears. It is usually associated with a very good outcome and minimal complications. In some patients with tight medial compartment, the posterior horn of the medial meniscus can be difficult to visualize, and access in this area with instruments may be challenging. To increase the opening of the medial compartment, after valgus-extension stress position of the knee, different techniques of deep medial collateral ligament release have been described. The outside-in pie-crusting technique shown in this technical note has documented effectiveness and good outcomes with minimal or no morbidity.

Posterior medial meniscus detachment: a unique type of medial meniscal tear.

PubMed

Rubinstein, Richard A; DeHaan, Alex; Baldwin, James L

2009-10-01

Patients with posterior medial meniscal detachment, as determined at knee arthroscopy, were evaluated retrospectively. Mean follow-up was 5.3 years for 8 men and 20 women (30 knees; mean age, 57 years). Most patients had acute onset of pain with a minor specific incident. Seventeen patients were obese, 9 were overweight, and 2 were normal. Eleven of 22 magnetic resonance imaging evaluations detected a tear at the site of the posterior medial meniscus root. Nine of 16 bone scan evaluations showed moderate uptake medially. Arthroscopic treatment included partial medial meniscectomy or meniscal repair. Twelve knees (40%) showed significant progression of arthritis. Of the 7 patients with severe arthritic knees, 5 have subsequently undergone total knee arthroplasty, 1 is considering total knee arthroplasty, and the other has minimal symptoms. Patients should be counseled about the clinical course of posterior medial meniscus detachment and its potential for progressive arthritis in the joint.

Paired-housing selectively facilitates within-session extinction of avoidance behavior, and increases c-Fos expression in the medial prefrontal cortex, in anxiety vulnerable Wistar-Kyoto rats.

PubMed

Smith, Ian M; Pang, Kevin C H; Servatius, Richard J; Jiao, Xilu; Beck, Kevin D

2016-10-01

The perseveration of avoidance behavior, even in the absence of once threatening stimuli, is a key feature of anxiety and related psychiatric conditions. This phenomenon can be observed in the Wistar-Kyoto (WKY) rat which, in comparison to outbred controls, demonstrates impaired extinction of avoidance behavior. Also characteristic of the WKY rat is abnormalities of the neurocircuitry and neuroplasticity of the medial prefrontal cortex (mPFC). One means of reducing physiological responses to anxiety, and conditioned fear, in social species is the presence of a conspecific animal. The current study investigates whether or not pair-housed WKY rats would show facilitated extinction of avoidance in comparison to individual-housed WKY rats, and whether or not pair-housing influences mPFC activation during lever-press avoidance. Male WKY rats were assigned to individual-housed and pair-housed conditions. Rats were trained in lever-press avoidance. Each session of lever-press avoidance consisted of 20 trials, where pressing a lever in response to a warning tone prevented foot-shocks. Rats received 12 acquisition sessions over 4weeks; followed by 6 extinction sessions over 2weeks, where foot-shocks ceased to be delivered. Brains were harvested 90min after trials 1 and 10 of extinction sessions 1 and 6, and mPFC sections underwent c-Fos staining as a measure of activation. Pair-housed rats showed facilitated lever-press avoidance extinction rates, but the main cause for this overall difference was a selective facilitation of within-session extinction. Similar to individual-housed rats, pair-housed rats continued to avoid during trial 1 of extinction even when the avoidance responding had been significantly reduced by the end of the previous session. Pair-housed rats sacrificed on trial 1 showed greater c-Fos expression in the anterior cingulate cortex and prelimbic cortex subregions of the mPFC compared individual-housed rats sacrificed on trial 1. This data shows pair

Parietal lobe critically supports successful paired immediate and single-item delayed memory for targets.

PubMed

Krumm, Sabine; Kivisaari, Sasa L; Monsch, Andreas U; Reinhardt, Julia; Ulmer, Stephan; Stippich, Christoph; Kressig, Reto W; Taylor, Kirsten I

2017-05-01

The parietal lobe is important for successful recognition memory, but its role is not yet fully understood. We investigated the parietal lobes' contribution to immediate paired-associate memory and delayed item-recognition memory separately for hits (targets) and correct rejections (distractors). We compared the behavioral performance of 56 patients with known parietal and medial temporal lobe dysfunction (i.e. early Alzheimer's Disease) to 56 healthy control participants in an immediate paired and delayed single item object memory task. Additionally, we performed voxel-based morphometry analyses to investigate the functional-neuroanatomic relationships between performance and voxel-based estimates of atrophy in whole-brain analyses. Behaviorally, all participants performed better identifying targets than rejecting distractors. The voxel-based morphometry analyses associated atrophy in the right ventral parietal cortex with fewer correct responses to familiar items (i.e. hits) in the immediate and delayed conditions. Additionally, medial temporal lobe integrity correlated with better performance in rejecting distractors, but not in identifying targets, in the immediate paired-associate task. Our findings suggest that the parietal lobe critically supports successful immediate and delayed target recognition memory, and that the ventral aspect of the parietal cortex and the medial temporal lobe may have complementary preferences for identifying targets and rejecting distractors, respectively, during recognition memory. Copyright © 2017. Published by Elsevier Inc.

Larger medial femoral to tibial condylar dimension may trigger posterior root tear of medial meniscus.

PubMed

Chung, Jun Young; Song, Hyung Keun; Jung, Myung Kuk; Oh, Hyeong Tak; Kim, Joon Ho; Yoon, Ji-Sang; Min, Byoung-Hyun

2016-05-01

The major meniscal functions are load bearing, load distribution, and shock absorption by increasing the tibiofemoral joint (TFJ) contact area and dissipating axial loads by conversion into hoop stresses. The increased hoop strain stretches the meniscus in outward direction towards radius, causing extrusion, which is associated with the root tear and resultant degenerative osteoarthritis. Since the larger contact area of medial TFJ may increase the hoop stresses, we hypothesized that the larger medial femoral to tibial condylar dimension would contribute to the development of medial meniscus posterior root tear (MMPRT). Thus, the purpose of the study was to assess the relationship between MMPRT and medial femoral to tibial condylar dimension. A case-control study was conducted to compare medial femoral to tibial condylar dimensions of patients with complete MMPRT (n = 59) with those of demography-matched controls (n = 59) during the period from 2010 to 2013. In each patient, MRIs were reviewed and several parameters were measured including articulation width of medial femoral condyle (MFC) at 0°, 30°, 60°, and 90°, medial tibial condyle (MTC) width, degree of meniscal extrusion, and medial femoral to tibial condylar width ratio (MFC/MTC) at 0°, 30°, 60°, and 90°, respectively. Demographic and radiographic data were assessed. A larger medial femoral to tibial condylar dimension was associated with MMPRT at 0° and 30° knee angles. Patients with MFC/MTC greater than 0.9 at 0° also showed about 2.5-fold increase in the chance of MMPRT. Those with meniscal extrusion greater than 3 mm also had about 17.1 times greater chance for the presence of MMPRT accordingly. A larger medial femoral to tibial condylar dimension may be considered as one of the regional contributors to the outbreak of MMPRT, and medial femoral to tibial condylar width ratio greater than 0.9 at 0° knee angle may be considered as a significant risk factor for MMPRT. III.

The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis.

PubMed

Resorlu, Mustafa; Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

2017-12-01

This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p < 0.001 and p = 0.018, respectively). Significant correlation was observed between medial meniscal tear and bursitis in the medial compartment (p = 0.038). Presence of medial periarticular bursitis was positively correlated with severity of osteoarthritis but exhibited no correlation with chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear.

The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis

PubMed Central

Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

2017-01-01

Abstract Background This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Patients and methods Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Results Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p < 0.001 and p = 0.018, respectively). Significant correlation was observed between medial meniscal tear and bursitis in the medial compartment (p = 0.038). Presence of medial periarticular bursitis was positively correlated with severity of osteoarthritis but exhibited no correlation with chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. Conclusions We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear. PMID:29333118

Drosophila Neprilysins Are Involved in Middle-Term and Long-Term Memory.

PubMed

Turrel, Oriane; Lampin-Saint-Amaux, Aurélie; Préat, Thomas; Goguel, Valérie

2016-09-14

Neprilysins are type II metalloproteinases known to degrade and inactivate a number of small peptides. Neprilysins in particular are the major amyloid-β peptide-degrading enzymes. In mouse models of Alzheimer's disease, neprilysin overexpression improves learning and memory deficits, whereas neprilysin deficiency aggravates the behavioral phenotypes. However, whether these enzymes are involved in memory in nonpathological conditions is an open question. Drosophila melanogaster is a well suited model system with which to address this issue. Several memory phases have been characterized in this organism and the neuronal circuits involved are well described. The fly genome contains five neprilysin-encoding genes, four of which are expressed in the adult. Using conditional RNA interference, we show here that all four neprilysins are involved in middle-term and long-term memory. Strikingly, all four are required in a single pair of neurons, the dorsal paired medial (DPM) neurons that broadly innervate the mushroom bodies (MBs), the center of olfactory memory. Neprilysins are also required in the MB, reflecting the functional relationship between the DPM neurons and the MB, a circuit believed to stabilize memories. Together, our data establish a role for neprilysins in two specific memory phases and further show that DPM neurons play a critical role in the proper targeting of neuropeptides involved in these processes. Neprilysins are endopeptidases known to degrade a number of small peptides. Neprilysin research has essentially focused on their role in Alzheimer's disease and heart failure. Here, we use Drosophila melanogaster to study whether neprilysins are involved in memory. Drosophila can form several types of olfactory memory and the neuronal structures involved are well described. Four neprilysin genes are expressed in adult Drosophila Using conditional RNA interference, we show that all four are specifically involved in middle-term memory (MTM) and long

Implementation of the DPM Monte Carlo code on a parallel architecture for treatment planning applications.

PubMed

Tyagi, Neelam; Bose, Abhijit; Chetty, Indrin J

2004-09-01

We have parallelized the Dose Planning Method (DPM), a Monte Carlo code optimized for radiotherapy class problems, on distributed-memory processor architectures using the Message Passing Interface (MPI). Parallelization has been investigated on a variety of parallel computing architectures at the University of Michigan-Center for Advanced Computing, with respect to efficiency and speedup as a function of the number of processors. We have integrated the parallel pseudo random number generator from the Scalable Parallel Pseudo-Random Number Generator (SPRNG) library to run with the parallel DPM. The Intel cluster consisting of 800 MHz Intel Pentium III processor shows an almost linear speedup up to 32 processors for simulating 1 x 10(8) or more particles. The speedup results are nearly linear on an Athlon cluster (up to 24 processors based on availability) which consists of 1.8 GHz+ Advanced Micro Devices (AMD) Athlon processors on increasing the problem size up to 8 x 10(8) histories. For a smaller number of histories (1 x 10(8)) the reduction of efficiency with the Athlon cluster (down to 83.9% with 24 processors) occurs because the processing time required to simulate 1 x 10(8) histories is less than the time associated with interprocessor communication. A similar trend was seen with the Opteron Cluster (consisting of 1400 MHz, 64-bit AMD Opteron processors) on increasing the problem size. Because of the 64-bit architecture Opteron processors are capable of storing and processing instructions at a faster rate and hence are faster as compared to the 32-bit Athlon processors. We have validated our implementation with an in-phantom dose calculation study using a parallel pencil monoenergetic electron beam of 20 MeV energy. The phantom consists of layers of water, lung, bone, aluminum, and titanium. The agreement in the central axis depth dose curves and profiles at different depths shows that the serial and parallel codes are equivalent in accuracy.

Traumatic posterior root tear of the medial meniscus in patients with severe medial instability of the knee.

PubMed

Ra, Ho Jong; Ha, Jeong Ku; Jang, Ho Su; Kim, Jin Goo

2015-10-01

To examine the incidence and diagnostic rate of traumatic medial meniscus posterior root tear associated with severe medial instability and to evaluate the effectiveness of pullout repair. From 2007 to 2011, 51 patients who underwent operation due to multiple ligament injuries including medial collateral ligament rupture were reviewed retrospectively. The International Knee Documentation Committee (IKDC) subjective and Lysholm score were evaluated pre- and postoperatively. Postoperative magnetic resonance imaging (MRI) was performed, and if indicated, a second-look arthroscopic examination was conducted. Fourteen out of 51 patients were associated with severe medial instability. Seven patients were diagnosed with traumatic medial meniscus posterior root tear and underwent arthroscopic pullout repair. Five of them were missed at initial diagnosis using MRI. In seven patients, the mean Lysholm and IKDC subjective scores improved from 74.6 ± 10.3 and 47.6 ± 7.3 to 93.0 ± 3.7 and 91.6 ± 2.6, respectively. All showed complete healing of meniscus root on follow-up MRI and second-look arthroscopy. Medial meniscus posterior root tear may occur in severe medial instability from trauma. It is a common mistake that surgeons may not notice on the diagnosis of those injuries using MRI. Therefore, a high index of suspicion is required for the diagnosis of medial meniscus posterior root tear in this type of injuries. The traumatic medial meniscus posterior root tear could be healed successfully using arthroscopic pullout repair technique. The possibility of the medial meniscus posterior root tear should be considered in severe medial instability and arthroscopic pullout repair can be an effective option for treatment. Case series with no comparison group, Level IV.

A Pencil Rescues Impaired Performance on a Visual Discrimination Task in Patients with Medial Temporal Lobe Lesions

ERIC Educational Resources Information Center

Knutson, Ashley R.; Hopkins, Ramona O.; Squire, Larry R.

2013-01-01

We tested proposals that medial temporal lobe (MTL) structures support not just memory but certain kinds of visual perception as well. Patients with hippocampal lesions or larger MTL lesions attempted to identify the unique object among twin pairs of objects that had a high degree of feature overlap. Patients were markedly impaired under the more…

Diminished medial prefrontal cortex activation during the recollection of stressful events is an acquired characteristic of PTSD.

PubMed

Dahlgren, M K; Laifer, L M; VanElzakker, M B; Offringa, R; Hughes, K C; Staples-Bradley, L K; Dubois, S J; Lasko, N B; Hinojosa, C A; Orr, S P; Pitman, R K; Shin, L M

2018-05-01

Previous research has shown relatively diminished medial prefrontal cortex activation and heightened psychophysiological responses during the recollection of personal events in post-traumatic stress disorder (PTSD), but the origin of these abnormalities is unknown. Twin studies provide the opportunity to determine whether such abnormalities reflect familial vulnerabilities, result from trauma exposure, or are acquired characteristics of PTSD. In this case-control twin study, 26 male identical twin pairs (12 PTSD; 14 non-PTSD) discordant for PTSD and combat exposure recalled and imagined trauma-unrelated stressful and neutral life events using a standard script-driven imagery paradigm during functional magnetic resonance imaging and concurrent skin conductance measurement. Diminished activation in the medial prefrontal cortex during Stressful v. Neutral script-driven imagery was observed in the individuals with PTSD, relative to other groups. Diminished medial prefrontal cortex activation during Stressful v. Neutral script-driven imagery may be an acquired characteristic of PTSD. If replicated, this finding could be used prospectively to inform diagnosis and the assessment of treatment response.

The Medial Stitch in Transosseous-Equivalent Rotator Cuff Repair: Vertical or Horizontal Mattress?

PubMed

Montanez, Anthony; Makarewich, Christopher A; Burks, Robert T; Henninger, Heath B

2016-09-01

Despite advances in surgical technique, rotator cuff repair retears continue to occur at rates of 10%, 22%, and 57% for small, medium, and large tears, respectively. A common mode of failure in transosseous-equivalent rotator cuff repairs is tissue pullout of the medial mattress stitch. While the medial mattress stitch has been studied extensively, no studies have evaluated a vertical mattress pattern placed near the musculotendinous junction in comparison with a horizontal mattress pattern. Vertical mattress stitches will have higher load to failure and lower gapping compared with horizontal mattress stitches in a transosseous-equivalent rotator cuff repair. Controlled laboratory study. Double-row transosseous-equivalent rotator cuff repairs were performed in 9 pairs of human male cadaveric shoulders (mean age ± SD, 58 ± 10 years). One shoulder in each pair received a medial-row suture pattern using a vertical mattress stitch, and the contralateral shoulder received a horizontal mattress. Specimens were mounted in a materials testing machine and tested in uniaxial tensile deformation for cyclic loading (500 cycles at 1 Hz to 1.0 MPa of effective stress), followed by failure testing carried out at a rate of 1 mm/s. Construct gapping and applied loads were monitored continuously throughout the testing. Vertical mattress sutures were placed in 5 right and 4 left shoulders. Peak cyclic gapping did not differ between vertical (mean ± SD, 2.8 ± 1.1 mm) and horizontal mattress specimens (3.0 ± 1.2 mm) (P = .684). Vertical mattress sutures failed at higher loads compared with horizontal mattress sutures (568.9 ± 140.3 vs 451.1 ± 174.3 N; P = .025); however, there was no significant difference in failure displacement (8.0 ± 1.6 vs 6.0 ± 2.1 mm; P = .092). Failure stiffness did not differ between the suture patterns (P = .204). In transosseous-equivalent rotator cuff repairs near the musculotendinous junction, a vertical mattress suture used as the medial stitch

The medial femoral wall can play a more important role in unstable intertrochanteric fractures compared with lateral femoral wall: a biomechanical study.

PubMed

Nie, Boyuan; Chen, Xueying; Li, Jing; Wu, Dou; Liu, Qiang

2017-12-28

The major objective of the present study is to investigate the differences in the load and strain changes in the intertrochanteric region of human cadaveric femora between the loss of medial or lateral wall and after treatment with proximal femoral nail antirotation (PFNA). After measuring the geometry of the proximal femur region and modeling the medial or lateral wall defect femoral models, six pairs of freshly frozen human femora were randomly assigned in the medial or lateral wall group. According to a single-leg stance model, an axial loading was applied, and the strain distribution was measured before and after PFNA implantation. The strains of each specimen were recorded at load levels of 350, 700, and 1800 N and the failure load. Paired t test was performed to assess the differences between two groups. The failure mode of almost all defect model femora was consistent with that of the simulated type of intertrochanteric fractures. After the PFNA implantation, the failure mode of almost all stabilized femora was caused by new lateral wall fractures. The failure load of the lateral wall group for defect model femora was significantly higher than that of the medial wall group (p < 0.001). However, the difference disappeared after the PFNA was implanted (p = 0.990). The axial stiffness in all defect model femora showed the same results (p < 0.001). After the PFNA implantation, the axial stiffness of the lateral wall group remained higher than that of the medial wall group (p = 0.001). However, the axial stiffness of the lateral wall group showed that the femora removed from the lateral wall were higher than the PFNA-stabilized femora (p = 0.020). For the axial strain in the anterior wall after the PFNA implantation, the strain of the lateral wall group was significantly lower than that of the medial group (p = 0.003). Nevertheless, for the axial strain of the posterior wall after the PFNA implantation, the strain of the medial wall group

Biomechanical investigation of two plating systems for medial column fusion in foot

PubMed Central

Simons, Paul; Sommerer, Theresia; Zderic, Ivan; Wahl, Dieter; Lenz, Mark; Skulev, Hristo; Knobe, Matthias; Gueorguiev, Boyko; Richards, R. Geoff; Klos, Kajetan

2017-01-01

Background Arthrodesis of the medial column (navicular, cuneiform I and metatarsal I) is performed for reasons such as Charcot arthropathy, arthritis, posttraumatic reconstruction or severe pes planus. However, the complication rate is still high and mainly resulting from inadequate fixation. Special plates, designed for medial column arthrodesis, seem to offer potential to reduce the complication rate. The aim of this study was to investigate biomechanically plantar and dorsomedial fusion of the medial column using two new plating systems. Methods Eight matched pairs of human cadaveric lower legs were randomized in two groups and medial column fusion was performed using either plantar or dorsomedial variable-angle locking compression plates. The specimens were biomechanically tested under cyclic progressively increasing axial loading with physiological profile of each cycle. In addition to the machine data, mediolateral x-rays were taken every 250 cycles and motion tracking was performed to determine movements at the arthrodesis site. Statistical analysis of the parameters of interest was performed at a level of significance p = 0.05. Results Displacement of the talo-navicular joint after 1000, 2000 and 4000 cycles was significantly lower for plantar plating (p≤0.039) while there was significantly less movement in the naviculo-cuneiform I joint for dorsal plating post these cycle numbers (p<0.001). Displacements in all three joints of the medial column, as well as angular and torsional deformations between the navicular and metatarsal I increased significantly for each plating technique between 1000, 2000 and 4000 cycles (p≤0.021). The two plating systems did not differ significantly with regard to stiffness and cycles to failure (p≥0.171). Conclusion From biomechanical point of view, although dorsomedial plating showed less movement than plantar plating in the current setup under dynamic loading, there was no significant difference between the two plating

Biomechanical investigation of two plating systems for medial column fusion in foot.

PubMed

Simons, Paul; Sommerer, Theresia; Zderic, Ivan; Wahl, Dieter; Lenz, Mark; Skulev, Hristo; Knobe, Matthias; Gueorguiev, Boyko; Richards, R Geoff; Klos, Kajetan

2017-01-01

Arthrodesis of the medial column (navicular, cuneiform I and metatarsal I) is performed for reasons such as Charcot arthropathy, arthritis, posttraumatic reconstruction or severe pes planus. However, the complication rate is still high and mainly resulting from inadequate fixation. Special plates, designed for medial column arthrodesis, seem to offer potential to reduce the complication rate. The aim of this study was to investigate biomechanically plantar and dorsomedial fusion of the medial column using two new plating systems. Eight matched pairs of human cadaveric lower legs were randomized in two groups and medial column fusion was performed using either plantar or dorsomedial variable-angle locking compression plates. The specimens were biomechanically tested under cyclic progressively increasing axial loading with physiological profile of each cycle. In addition to the machine data, mediolateral x-rays were taken every 250 cycles and motion tracking was performed to determine movements at the arthrodesis site. Statistical analysis of the parameters of interest was performed at a level of significance p = 0.05. Displacement of the talo-navicular joint after 1000, 2000 and 4000 cycles was significantly lower for plantar plating (p≤0.039) while there was significantly less movement in the naviculo-cuneiform I joint for dorsal plating post these cycle numbers (p<0.001). Displacements in all three joints of the medial column, as well as angular and torsional deformations between the navicular and metatarsal I increased significantly for each plating technique between 1000, 2000 and 4000 cycles (p≤0.021). The two plating systems did not differ significantly with regard to stiffness and cycles to failure (p≥0.171). From biomechanical point of view, although dorsomedial plating showed less movement than plantar plating in the current setup under dynamic loading, there was no significant difference between the two plating systems with regard to stiffness and

Bilateral discoid medial menisci: a rare phenomenon

PubMed Central

Samal, Puspak; Bhagwat, Kishan; Panigrahi, Tapas; Gopinathan, Nirmalraj

2014-01-01

Discoid medial meniscus is a relatively rare pathology of the knee joint, with bilateral cases even rarer. Herein, we report the case of a 25-year-old man diagnosed with discoid medial meniscus in the right knee with a horizontal tear. Increased cupping of the medial condyle of the tibia, widening of the medial joint space and the presence of discoid meniscus in the right knee prompted investigation of the asymptomatic left knee with magnetic resonance imaging. The contralateral asymptomatic knee also showed evidence of discoid medial meniscus. The symptomatic knee was successfully treated by arthroscopic partial meniscectomy, with excellent functional outcome. PMID:25273941

Medial Patella Subluxation: Diagnosis and Treatment

PubMed Central

McCarthy, Mark A.; Bollier, Mathew J.

2015-01-01

Medial patella subluxation is a disabling condition typically associated with previous patellofemoral instability surgery. Patients often describe achy pain with painful popping episodes. They often report that the patella shifts laterally, which occurs as the medial subluxed patella dramatically shifts into the trochlear groove during early knee flexion. Physical examination is diagnostic with a positive medial subluxation test. Nonoperative treatment, such as focused physical therapy and patellofemoral stabilizing brace, is often unsuccessful. Primary surgical options include lateral retinacular repair/imbrication or lateral reconstruction. Prevention is key to avoid medial patella subluxation. When considering patellofemoral surgery, important factors include appropriate lateral release indications, consideration of lateral retinacular lengthening vs release, correct MPFL graft placement and tension, and avoiding excessive medialization during tubercle transfer. This review article will analyze patient symptoms, diagnostic exam findings and appropriate treatment options, as well as pearls to avoid this painful clinical entity. PMID:26361441

A Systematic Review of Clinical Functional Outcomes After Medial Stabilized Versus Non-Medial Stabilized Total Knee Joint Replacement

PubMed Central

Young, Tony; Dowsey, Michelle M.; Pandy, Marcus; Choong, Peter F.

2018-01-01

Background Medial stabilized total knee joint replacement (TKJR) construct is designed to closely replicate the kinematics of the knee. Little is known regarding comparison of clinical functional outcomes of patients utilising validated patient reported outcome measures (PROM) after medial stabilized TKJR and other construct designs. Purpose To perform a systematic review of the available literature related to the assessment of clinical functional outcomes following a TKJR employing a medial stabilized construct design. Methods The review was performed with a Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) algorithm. The literature search was performed using variouscombinations of keywords. The statistical analysis was completed using Review Manager (RevMan), Version 5.3. Results In the nineteen unique studies identified, there were 2,448 medial stabilized TKJRs implanted in 2,195 participants, there were 1,777 TKJRs with non-medial stabilized design constructs implanted in 1,734 subjects. The final mean Knee Society Score (KSS) value in the medial stabilized group was 89.92 compared to 90.76 in the non-medial stabilized group, with the final KSS mean value difference between the two groups was statistically significant and favored the non-medial stabilized group (SMD 0.21; 95% CI: 0.01 to 0.41; p = 004). The mean difference in the final WOMAC values between the two groups was also statistically significant and favored the medial stabilized group (SMD: −0.27; 95% CI: −0.47 to −0.07; p = 0.009). Moderate to high values (I2) of heterogeneity were observed during the statistical comparison of these functional outcomes. Conclusion Based on the small number of studies with appropriate statistical analysis, we are unable to reach a clear conclusion in the clinical performance of medial stabilized knee replacement construct. Level of Evidence Level II PMID:29696144

A Systematic Review of Clinical Functional Outcomes After Medial Stabilized Versus Non-Medial Stabilized Total Knee Joint Replacement.

PubMed

Young, Tony; Dowsey, Michelle M; Pandy, Marcus; Choong, Peter F

2018-01-01

Medial stabilized total knee joint replacement (TKJR) construct is designed to closely replicate the kinematics of the knee. Little is known regarding comparison of clinical functional outcomes of patients utilising validated patient reported outcome measures (PROM) after medial stabilized TKJR and other construct designs. To perform a systematic review of the available literature related to the assessment of clinical functional outcomes following a TKJR employing a medial stabilized construct design. The review was performed with a Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) algorithm. The literature search was performed using variouscombinations of keywords. The statistical analysis was completed using Review Manager (RevMan), Version 5.3. In the nineteen unique studies identified, there were 2,448 medial stabilized TKJRs implanted in 2,195 participants, there were 1,777 TKJRs with non-medial stabilized design constructs implanted in 1,734 subjects. The final mean Knee Society Score (KSS) value in the medial stabilized group was 89.92 compared to 90.76 in the non-medial stabilized group, with the final KSS mean value difference between the two groups was statistically significant and favored the non-medial stabilized group (SMD 0.21; 95% CI: 0.01 to 0.41; p = 004). The mean difference in the final WOMAC values between the two groups was also statistically significant and favored the medial stabilized group (SMD: -0.27; 95% CI: -0.47 to -0.07; p = 0.009). Moderate to high values ( I 2 ) of heterogeneity were observed during the statistical comparison of these functional outcomes. Based on the small number of studies with appropriate statistical analysis, we are unable to reach a clear conclusion in the clinical performance of medial stabilized knee replacement construct. Level II.

Medial cortex activity, self-reflection and depression.

PubMed

Johnson, Marcia K; Nolen-Hoeksema, Susan; Mitchell, Karen J; Levin, Yael

2009-12-01

Using functional magnetic resonance imaging, we investigated neural activity associated with self-reflection in depressed [current major depressive episode (MDE)] and healthy control participants, focusing on medial cortex areas previously shown to be associated with self-reflection. Both the MDE and healthy control groups showed greater activity in anterior medial cortex (medial frontal gyrus, anterior cingulate gyrus) when cued to think about hopes and aspirations compared with duties and obligations, and greater activity in posterior medial cortex (precuneus, posterior cingulate) when cued to think about duties and obligations (Experiment 1). However, the MDE group showed less activity than controls in the same area of medial frontal cortex when self-referential cues were more ambiguous with respect to valence (Experiment 2), and less deactivation in a non-self-referential condition in both experiments. Furthermore, individual differences in rumination were positively correlated with activity in both anterior and posterior medial cortex during non-self-referential conditions. These results provide converging evidence for a dissociation of anterior and posterior medial cortex depending on the focus of self-relevant thought. They also provide neural evidence consistent with behavioral findings that depression is associated with disruption of positively valenced thoughts in response to ambiguous cues, and difficulty disengaging from self-reflection when it is appropriate to do so.

Medial cortex activity, self-reflection and depression

PubMed Central

Nolen-Hoeksema, Susan; Mitchell, Karen J.; Levin, Yael

2009-01-01

Using functional magnetic resonance imaging, we investigated neural activity associated with self-reflection in depressed [current major depressive episode (MDE)] and healthy control participants, focusing on medial cortex areas previously shown to be associated with self-reflection. Both the MDE and healthy control groups showed greater activity in anterior medial cortex (medial frontal gyrus, anterior cingulate gyrus) when cued to think about hopes and aspirations compared with duties and obligations, and greater activity in posterior medial cortex (precuneus, posterior cingulate) when cued to think about duties and obligations (Experiment 1). However, the MDE group showed less activity than controls in the same area of medial frontal cortex when self-referential cues were more ambiguous with respect to valence (Experiment 2), and less deactivation in a non-self-referential condition in both experiments. Furthermore, individual differences in rumination were positively correlated with activity in both anterior and posterior medial cortex during non-self-referential conditions. These results provide converging evidence for a dissociation of anterior and posterior medial cortex depending on the focus of self-relevant thought. They also provide neural evidence consistent with behavioral findings that depression is associated with disruption of positively valenced thoughts in response to ambiguous cues, and difficulty disengaging from self-reflection when it is appropriate to do so. PMID:19620180

Comparison of complete distal release of the medial collateral ligament and medial epicondylar osteotomy during ligament balancing in varus knee total knee arthroplasty.

PubMed

Sim, Jae Ang; Lee, Yong Seuk; Kwak, Ji Hoon; Yang, Sang Hoon; Kim, Kwang Hui; Lee, Beom Koo

2013-12-01

During ligament balancing for severe medial contracture in varus knee total knee arthroplasty (TKA), complete distal release of the medial collateral ligament (MCL) or a medial epicondylar osteotomy can be necessary if a large amount of correction is needed. This study retrospectively reviewed 9 cases of complete distal release of the MCL and 11 cases of medial epicondylar osteotomy which were used to correct severe medial contracture. The mean follow-up periods were 46.5 months (range, 36 to 78 months) and 39.8 months (range, 32 to 65 months), respectively. There were no significant differences in the clinical results between the two groups. However, the valgus stress radiograph revealed significant differences in medial instability. In complete distal release of the MCL, some stability was obtained by repair and bracing but the medial instability could not be removed completely. Medial epicondylar osteotomy for a varus deformity in TKA could provide constant medial stability and be a useful ligament balancing technique.

[SPECIFIC DIAGNOSTIC SIGNIFICANCE OF "RIPPLE SIGN" OF MEDIAL FEMORAL CONDYLE UNDER ARTHROSCOPE IN MEDIAL LONGITUDINAL MENISCAL TEARS].

PubMed

Ren Shiyou; Sun, Limang; Chen, Guofei; Jiang, Changqing; Zhang, Xintao; Zhang Wentao

2015-01-01

To investigate the reliability of the "ripple sign" on the upper surface of the medial femoral condyle in the diagnosis of medial longitudinal meniscal tears under arthroscope. Between June 2013 and June 2014, 56 patients with knee injuries were included. There were 35 males and 21 females with an average age of 22.2 years (range, 12-38 years). The causes of injury were sports in 40 cases, falling in 10 cases, and traffic accident in 6 cases. The injury was located at the left knee in 22 cases and at the right knee in 34 cases. The disease duration was 10-40 days (mean, 20.2 days). Of 56 patients, 15 cases had simple medial meniscal injury; 41 cases had combined injuries, including anterior cruciate ligament injury in 38 cases, posterior cruciate ligament injury in 2 cases, and patellar dislocation in 1 case. The "ripple sign" was observed under arthroscope before operation. Repair of medial meniscal injury and reconstruction of cruciate ligament were performed. The positive "ripple sign" was seen under arthroscope in all patients, who were diagnosed to have longitudinal meniscal tears, including 23 cases of mild "ripple sign" , 28 cases of moderate "ripple sign", and 5 cases of severe "ripple sign". The "ripple sign" on the upper surface of the medial femoral condyle is a reliable diagnostic evidence of medial longitudinal meniscal tears.

Medial extrusion of the posterior segment of medial meniscus is a sensitive sign for posterior horn tears.

PubMed

Ohishi, Tsuyoshi; Suzuki, Daisuke; Yamamoto, Kazufumi; Banno, Tomohiro; Shimizu, Yuta; Matsuyama, Yukihiro

2014-01-01

To evaluate medial extrusion of the posterior segment of the medial meniscus in posterior horn tears. This study enrolled 72 patients without medial meniscal tears (group N), 72 patients with medial meniscal tears without posterior horn tears (group PH-), 44 patients with posterior horn tears of the medial meniscus (group PH+). All meniscal tears were confirmed by arthroscopy. Medial extrusion of the middle segment and the posterior segment was measured on coronal MRIs. Extrusions of both middle and posterior segments in groups PH- and PH+ (middle segment; 2.94±1.51 mm for group PH- and 3.75±1.69 mm for group PH+, posterior segment; 1.85±1.82 mm for group PH- and 4.59±2.74 mm for group PH+) were significantly larger than those in group N (middle segment; 2.04±1.20, posterior segment; 1.21±1.86). Both indicators of extrusion in group PH+ were larger than those in group PH-. In the early OA category, neither middle nor posterior segment in group PH- extruded more than in group N. However, only the posterior segment in group PH+ extruded significantly more than in group N. Multiple lineal regression analyses revealed that posterior segment extrusion was strongly correlated with the posterior horn tears (p<0.001) among groups PH- and PH+. The newly presented indicator for extrusion of the posterior segment of the medial meniscus is associated with posterior horn tears in comparison with the extrusion of the middle segment, especially in the early stages of osteoarthritis. Level II--Diagnostic Study. Copyright © 2013 Elsevier B.V. All rights reserved.

Selective Medial Release Technique Using the Pie-Crusting Method for Medial Tightness During Primary Total Knee Arthroplasty.

PubMed

Ha, Chul-Won; Park, Yong-Beom; Lee, Choong-Hee; Awe, Soo-Ik; Park, Yong-Geun

2016-05-01

The pie-crusting method is popular in releasing lateral tightness during primary total knee arthroplasty (TKA) but is not well described for medial release. We established a selective medial release technique using the pie-crusting technique and investigated the effectiveness and safety of the technique during primary TKA. We retrospectively reviewed 729 primary TKAs with varus deformity between October 2009 and June 2012. Medial tightness in flexion was released by traditional subperiosteal stripping for the anterior portion of the medial collateral ligament (aMCL). Medial tightness in extension was released by the pie crusting for the tight fibers in the posterior portion of the MCL and/or posteromedial corner structures (pMCL/PMCS). Clinical outcomes were evaluated by Knee Society (KS) scores and the Western Ontario and McMaster Universities Osteoarthritis Index. Any complications, including late medial instability that may be related to our surgical technique, were carefully inspected. Among the 729 knees, 170 (23.3%) required subperiosteal stripping for balancing in flexion only, 186 (25.5%) required the pie-crusting for balancing in extension only and 142 (19.5%) required subperiosteal stripping and the pie-crusting for balancing in flexion and extension. The KS knee score was improved from 52.5 to 83.4, KS function score from 58.2 to 91.9, and Western Ontario and McMaster Universities Osteoarthritis Index from 42.7 to 21.8 (P < .001, all). No specific complications related to our technique were identified. The selective medial release technique appears to be an effective and safe method to obtain a balanced mediolateral gap in primary TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

[Biological and neural bases of partner preferences in rodents: models to understand human pair bonds].

PubMed

Coria-Avila, G A; Hernández-Aguilar, M E; Toledo-Cárdenas, R; García-Hernández, L I; Manzo, J; Pacheco, P; Miquel, M; Pfaus, J G

To analyse the biological and neural bases of partner preference formation in rodents as models to understand human pair bonding. Rodents are social individuals, capable of forming short- or long-lasting partner preferences that develop slowly by stimuli like cohabitation, or rapidly by stimuli like sex and stress. Dopamine, corticosteroids, oxytocin, vasopressin, and opioids form the neurochemical substrate for pair bonding in areas like the nucleus accumbens, the prefrontal cortex, the piriform cortex, the medial preoptic area, the ventral tegmental area and the medial amygdala, among others. Additional areas may participate depending on the nature of the conditioned stimuli by which and individual recognizes a preferred partner. Animal models help us understand that the capacity of an individual to display long-lasting and selective preferences depends on neural bases, selected throughout evolution. The challenge in neuroscience is to use this knowledge to create new solutions for mental problems associated with the incapacity of an individual to display a social bond, keep one, or cope with the disruption of a consolidated one.

Endoscopic medial maxillectomy breaking new frontiers.

PubMed

Mohanty, Sanjeev; Gopinath, M

2013-07-01

Endoscopy has changed the perspective of rhinologist towards the nose. It has revolutionised the surgical management of sinonasal disorders. Sinus surgeries were the first to get the benefit of endoscope. Gradually the domain of endoscopic surgery extended to the management of sino nasal tumours. Traditionally medial maxillectomy was performed through lateral rhinotomy or mid facial degloving approach. Endoscopic medial maxillectomy has been advocated by a number of authors in the management of benign sino-nasal tumours. We present our experience of endoscopic medial maxillectomy in the management of sinonasal pathologies.

Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair.

PubMed

Virk, Mandeep S; Bruce, Benjamin; Hussey, Kristen E; Thomas, Jacqueline M; Luthringer, Tyler A; Shewman, Elizabeth F; Wang, Vincent M; Verma, Nikhil N; Romeo, Anthony A; Cole, Brian J

2017-02-01

To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model. A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system. The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing. In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure. In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure. Copyright © 2016. Published by Elsevier Inc.

Effects of foot orthoses with medial arch support and lateral wedge on knee adduction moment in patients with medial knee osteoarthritis.

PubMed

Dessery, Yoann; Belzile, Étienne; Turmel, Sylvie; Corbeil, Philippe

2017-08-01

There is contradictory evidence regarding whether the addition of medial arch supports to laterally wedged insoles reduces knee adduction moment, improves comfort, and reduces knee pain during the late stance phase of gait. To verify if such effects occur in participants with medial knee osteoarthritis. Randomized single-blinded study. Gait analysis was performed on 18 patients affected by medial knee osteoarthritis. Pain and comfort scores, frontal plane kinematics and kinetics of ankle, knee, and hip were compared in four conditions: without foot orthosis, with foot orthoses, with medial arch support, and with foot orthoses with medial arch support and lateral wedge insoles with 6° and 10° inclination. Lower-extremity gait kinetics were characterized by a significant decrease, greater than 6%, in second peak knee adduction moment in laterally wedged insole conditions compared to the other conditions ( p < 0.001; effect size = 0.6). No significant difference in knee adduction moment was observed between laterally wedged insole conditions. In contrast, a significant increase of 7% in knee adduction moment during the loading response was observed in the customized foot orthoses without lateral inclination condition ( p < 0.001; effect size = 0.3). No difference was found in comfort or pain ratings between conditions. Our study suggests that customized foot orthoses with a medial arch support may only be suitable for the management of medial knee osteoarthritis when a lateral wedge is included. Clinical relevance Our data suggest that customized foot orthoses with medial arch support and a lateral wedge reduce knee loading in patients with medial knee osteoarthritis (KOA). We also found evidence that medial arch support may increase knee loading, which could potentially be detrimental in KOA patients.

The Anatomy of the Medial Patellofemoral Complex.

PubMed

Tanaka, Miho J

2017-06-01

The term "medial patellofemoral complex" (MPFC) was proposed to describe the static medial stabilizer of the patella, typically referred to as the medial patellofemoral ligament. In light of our increasing understanding of the attachment of its fibers to the quadriceps tendon in addition to the patella, the term MPFC is used in this article. The purpose of this article is to describe and discuss the anatomy of the MPFC.

Arthroscopic pullout repair of posterior root tear of the medial meniscus: the anterior approach using medial collateral ligament pie-crusting release.

PubMed

Park, Young-Sik; Moon, Hong-Kyo; Koh, Yong-Gon; Kim, Yong-Chan; Sim, Dong-Sik; Jo, Seung-Bae; Kwon, Se-Kwang

2011-08-01

Posterior root tears of the medial meniscus are frequently encountered and should be repaired if possible to prevent osteoarthritis of the medial compartment. Various surgical techniques have been proposed to repair posterior root tears. The anterior arthroscopic approach can cause an iatrogenic chondral injury due to the narrow medial joint space. The posterior approaches might be technically unfamiliar to many surgeons because they require the establishment of a posteromedial or trans-septal portal. This paper describes the medial collateral ligament pie-crusting release technique for arthroscopic double transosseous pullout repair of posterior root tears of the medial meniscus through the anterior approach to provide the good visualization of the footprint and sufficient working space.

Medial meniscus posterior horn avulsion.

PubMed

Marzo, John M

2009-05-01

Avulsion of the posterior horn of the medial meniscus can occur from acute trauma or chronic degeneration, leading to meniscus extrusion, articular cartilage loss, osteophyte formation, and medial joint space narrowing. With meniscus extrusion, the meniscus is unable to resist hoop stresses and cannot shield the adjacent articular cartilage from excessive axial load. Over time, this can lead to symptomatic knee osteoarthritis. Patients typically report pain, swelling, mechanical symptoms, and general functional loss. Although nonsurgical care may relieve symptoms, it is unlikely to alter either the natural history of meniscal loss or the fate of the medial compartment. Surgical repair of posterior horn meniscal avulsion is done in an attempt to restore the anatomy and biomechanical function of the meniscus, and to slow or prevent degenerative joint disease. Meniscal transplantation is reserved for salvage situations.

Evidence that the medial amygdala projects to the anterior/ventromedial hypothalamic nuclei to inhibit maternal behavior in rats.

PubMed

Sheehan, T; Paul, M; Amaral, E; Numan, M J; Numan, M

2001-01-01

The maternal behaviors shown by a rat that has given birth are not shown by a virgin female rat when she is first presented with young. This absence of maternal behavior in virgins has been attributed to the activity of a neural circuit that inhibits maternal behavior in nulliparae. The medial amygdala and regions of the medial hypothalamus such as the anterior and ventromedial hypothalamic nuclei have previously been shown to inhibit maternal behavior, in that lesions to these regions promote maternal responding. Furthermore, we have recently shown that these and other regions, such as the principal bed nucleus of the stria terminalis, the ventral lateral septum, and the dorsal premammillary nucleus, show higher pup-induced Fos-immunoreactivity in non-maternal rats exposed to pups than during the performance of maternal behavior, indicating that they too could be involved in preventing maternal responsiveness. The current study tested whether the medial amygdala projects to the anterior/ventromedial hypothalamic nuclei in a neural circuit that inhibits maternal behavior, as well as to see what other brain regions could participate in this circuit. Bilateral excitotoxic lesions of the medial amygdala, or of the anterior/ventromedial hypothalamic nuclei, promoted maternal behavior. Unilateral medial amygdala lesions caused a reduction of pup-induced Fos-immunoreactivity in the anterior/ventromedial hypothalamic nuclei in non-maternal rats ipsilateral to the lesion, as well as in the principal bed nucleus of the stria terminalis, ventral lateral septum, and dorsal premammillary nucleus. Finally, unilateral medial amygdala lesions paired with contralateral anterior/ventromedial hypothalamic nuclei lesions promoted maternal behavior, although ipsilateral lesion placements were also effective.Together, these results indicate that the medial amygdala projects to the anterior/ventromedial hypothalamic nuclei in a neural circuit that inhibits maternal behavior, and that

Medial orbital wall reconstruction with flexible Ethisorb patches.

PubMed

Pohlenz, P; Adler, W; Li, L; Schmelzle, R; Klatt, J

2013-03-01

The aim of this study was to analyse the long-term result after reconstruction of the medial orbital wall with a flexible, biodegradable material (Ethisorb). During a period of almost 8 years, 31 patients with a medial orbital wall fracture were analysed retrospectively. Inclusion criteria were patients with a maximum size fracture of the orbital medial wall measuring 1.5-2 cm(2). Exophthalmos, enophthalmos, bulbus motility, diplopia and skin sensation were investigated over a period of 6 months. In all patients, the medial orbital wall was reconstructed with Ethisorb patches. No significant intraoperative complications were detected. No postoperative infection, abscess or seroma was found in any of the patients receiving an Ethisorb patch. The advantage of the semiflexibility of the Ethisorb patch is that it supplies an anatomically correct fit to the orbital medial wall but does not require fixation by screws or the use of sutures. The low rate of reported bulbus motility disturbance, diplopia, exophthalmos and enophthalmos demonstrates acceptable results after medial orbital wall reconstruction using the Ethisorb patch.

Transcriptomic Signature of the SHATTERPROOF2 Expression Domain Reveals the Meristematic Nature of Arabidopsis Gynoecial Medial Domain1[OPEN

PubMed Central

Villarino, Gonzalo H.; Hu, Qiwen; Flores-Vergara, Miguel; Sehra, Bhupinder; Brumos, Javier; Stepanova, Anna N.; Sundberg, Eva; Heber, Steffen

2016-01-01

Plant meristems, like animal stem cell niches, maintain a pool of multipotent, undifferentiated cells that divide and differentiate to give rise to organs. In Arabidopsis (Arabidopsis thaliana), the carpel margin meristem is a vital meristematic structure that generates ovules from the medial domain of the gynoecium, the female floral reproductive structure. The molecular mechanisms that specify this meristematic region and regulate its organogenic potential are poorly understood. Here, we present a novel approach to analyze the transcriptional signature of the medial domain of the Arabidopsis gynoecium, highlighting the developmental stages that immediately proceed ovule initiation, the earliest stages of seed development. Using a floral synchronization system and a SHATTERPROOF2 (SHP2) domain-specific reporter, paired with FACS and RNA sequencing, we assayed the transcriptome of the gynoecial medial domain with temporal and spatial precision. This analysis reveals a set of genes that are differentially expressed within the SHP2 expression domain, including genes that have been shown previously to function during the development of medial domain-derived structures, including the ovules, thus validating our approach. Global analyses of the transcriptomic data set indicate a similarity of the pSHP2-expressing cell population to previously characterized meristematic domains, further supporting the meristematic nature of this gynoecial tissue. Our method identifies additional genes including novel isoforms, cis-natural antisense transcripts, and a previously unrecognized member of the REPRODUCTIVE MERISTEM family of transcriptional regulators that are potential novel regulators of medial domain development. This data set provides genome-wide transcriptional insight into the development of the carpel margin meristem in Arabidopsis. PMID:26983993

Medial and Lateral Discoid Menisci of Both Knees

PubMed Central

Kan, Hiroyuki; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Minami, Ginjiro; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2016-01-01

Discoid menisci on both the medial and lateral sides are rare, and there are very few reports on cases involving both sides. We report a case of a 52-year-old female with medial and lateral discoid menisci in both knees. Arthroscopy revealed the lateral menisci of both knees were complete discoid menisci, and partial meniscectomy was performed. The medial menisci were incomplete discoid menisci, but there were no findings of abnormal mobility or injury; therefore, the medial menisci were observed without treatment. At six months postoperatively, her pain and range of motion restrictions disappeared. PMID:27894182

Persistently active neurons in human medial frontal and medial temporal lobe support working memory

PubMed Central

Kamiński, J; Sullivan, S; Chung, JM; Ross, IB; Mamelak, AN; Rutishauser, U

2017-01-01

Persistent neural activity is a putative mechanism for the maintenance of working memories. Persistent activity relies on the activity of a distributed network of areas, but the differential contribution of each area remains unclear. We recorded single neurons in the human medial frontal cortex and the medial temporal lobe while subjects held up to three items in memory. We found persistently active neurons in both areas. Persistent activity of hippocampal and amygdala neurons was stimulus-specific, formed stable attractors, and was predictive of memory content. Medial frontal cortex persistent activity, on the other hand, was modulated by memory load and task set but was not stimulus-specific. Trial-by-trial variability in persistent activity in both areas was related to memory strength, because it predicted the speed and accuracy by which stimuli were remembered. This work reveals, in humans, direct evidence for a distributed network of persistently active neurons supporting working memory maintenance. PMID:28218914

Proximal Tibia Medial Biplanar Retrotubercle Open Wedge Osteotomy for Varus Knees with Medial Gonarthrosis

PubMed Central

Türkmen, İsmail; Esenkaya, İrfan; Ünay, Koray; Türkmensoy, Fatih; Özkut, Afşar Timuçin

2014-01-01

Objectives: The purpose of this study is to evaluate the early results of proximal tibia medial biplanar retrotubercle open wedge osteotomy for varus gonarthrosis and compare the results with the literatüre. Methods: The results of proximal tibia medial biplanar retrotubercle open wedge osteotomy for 23 knees of 22 patients with medial gonarthrosis were evaluated clinically and radiologically. Results: Twenty of the patients were female and two were male. Mean age of the patients was 56.24; mean boy mass index was 31.95 and preoperative HSS (Hospital for Special Surgery) score was 68.7. Mean tibiofemoral axis was 186.39° and mean Insall-Salvatti index value was 1.04 preoperatively. Mean follow up period was 30.19 months. Mean HSS score was 86.48, femorotibial anatomic axis angle was 175° and Insall-Salvati index value 1.06 during the last follow-up. The improvement of the HSS score and the femorotibial anatomic axis angle was statistically significant. However, the change in Insall Salvati index values was statistically insignificant. Nonfatal pulmonary embolus in 1 patient, and deep vein thrombosis that occured one year after the procedure in 1 patient, rhabdomyolysis in 1 patient and loss of correction (relapse) in 1 patient were encountered as complications. Conclusion: Our results show that proximal tibia medial biplanar retrotubercle open wedge osteotomy improves the frontal and sagittal plane deformities without changing the patellar tendon length. Hence, possible patellofemoral problems are prevented and the clinical results are improved.

The timing of associative memory formation: frontal lobe and anterior medial temporal lobe activity at associative binding predicts memory

PubMed Central

Hales, J. B.

2011-01-01

The process of associating items encountered over time and across variable time delays is fundamental for creating memories in daily life, such as for stories and episodes. Forming associative memory for temporally discontiguous items involves medial temporal lobe structures and additional neocortical processing regions, including prefrontal cortex, parietal lobe, and lateral occipital regions. However, most prior memory studies, using concurrently presented stimuli, have failed to examine the temporal aspect of successful associative memory formation to identify when activity in these brain regions is predictive of associative memory formation. In the current study, functional MRI data were acquired while subjects were shown pairs of sequentially presented visual images with a fixed interitem delay within pairs. This design allowed the entire time course of the trial to be analyzed, starting from onset of the first item, across the 5.5-s delay period, and through offset of the second item. Subjects then completed a postscan recognition test for the items and associations they encoded during the scan and their confidence for each. After controlling for item-memory strength, we isolated brain regions selectively involved in associative encoding. Consistent with prior findings, increased regional activity predicting subsequent associative memory success was found in anterior medial temporal lobe regions of left perirhinal and entorhinal cortices and in left prefrontal cortex and lateral occipital regions. The temporal separation within each pair, however, allowed extension of these findings by isolating the timing of regional involvement, showing that increased response in these regions occurs during binding but not during maintenance. PMID:21248058

Stimulation of the medial amygdala enhances medial preoptic dopamine release: implications for male rat sexual behavior.

PubMed

Dominguez, J M; Hull, E M

2001-11-02

Increased dopamine (DA) in the medial preoptic area (MPOA) facilitates male sexual behavior. A major source of innervation to the MPOA is the medial amygdala (MeA). We now report that chemical stimulation of the MeA enhanced levels of extracellular MPOA DA in anesthetized male rats. These results suggest that DA activity in the MPOA can be regulated by input from the MeA to the MPOA.

An in vitro analysis of medial structures and a medial soft tissue reconstruction in a constrained condylar total knee arthroplasty.

PubMed

Athwal, Kiron K; El Daou, Hadi; Inderhaug, Eivind; Manning, William; Davies, Andrew J; Deehan, David J; Amis, Andrew A

2017-08-01

The aim of this study was to quantify the medial soft tissue contributions to stability following constrained condylar (CC) total knee arthroplasty (TKA) and determine whether a medial reconstruction could restore stability to a soft tissue-deficient, CC-TKA knee. Eight cadaveric knees were mounted in a robotic system and tested at 0°, 30°, 60°, and 90° of flexion with ±50 N anterior-posterior force, ±8 Nm varus-valgus, and ±5 Nm internal-external torque. The deep and superficial medial collateral ligaments (dMCL, sMCL) and posteromedial capsule (PMC) were transected and their relative contributions to stabilising the applied loads were quantified. After complete medial soft tissue transection, a reconstruction using a semitendinosus tendon graft was performed, and the effect on kinematic behaviour under equivocal conditions was measured. In the CC-TKA knee, the sMCL was the major medial restraint in anterior drawer, internal-external, and valgus rotation. No significant differences were found between the rotational laxities of the reconstructed knee to the pre-deficient state for the arc of motion examined. The relative contribution of the reconstruction was higher in valgus rotation at 60° than the sMCL; otherwise, the contribution of the reconstruction was similar to that of the sMCL. There is contention whether a CC-TKA can function with medial deficiency or more constraint is required. This work has shown that a CC-TKA may not provide enough stability with an absent sMCL. However, in such cases, combining the CC-TKA with a medial soft tissue reconstruction may be considered as an alternative to a hinged implant.

Medial Osteoectomy as a Routine Procedure in Rhinoplasty: Six-Year Experience with an Innovative Technique.

PubMed

Lykoudis, Efstathios G; Peristeri, Dimitra V; Lykoudis, Georgios E; Oikonomou, Georgios A

2018-02-01

Medial osteotomy is an integral part of most rhinoplasty procedures, and when improperly performed, it is associated with postoperative complications and nasal contour deformities. In this article, we present a minimally traumatic and easy-to-perform medial osteoectomy technique with a pair of pliers, as a routine procedure, instead of the traditional medial osteotomy with osteotome and hammer. We report our experience with the use of the technique in a series of rhinoplasty procedures and review in brief the existing literature. One hundred and thirty-five patients underwent rhinoplasty operations to correct aesthetic nose deformities, with the use of the suggested surgical technique. Two different types of medial osteoectomy, performed with the pliers, were used: Type I for dorsal nasal hump reduction and slight narrowing of the nose and type II for the management of a wide nasal dorsum along with or without hump removal. Postoperative results were favorable, by both clinical examination and comparison of preoperative and postoperative photographs, in 98.5% of patients. Only two patients with wide nasal dorsums had inadequate narrowing of their broad nose and underwent successful revision surgery. The suggested technique is easy to perform, has a short learning curve, provides high accuracy over the location and amount of the nasal bone to be removed, but inflicts minimal trauma. As a result of the aforementioned advantages, the risk of postoperative complications is low, and most importantly, reliable, consistent, and aesthetically pleasing results are easily ensured. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The percutaneous pie-crusting medial release during arthroscopic procedures of the medial meniscus does neither affect valgus laxity nor clinical outcome.

PubMed

Jeon, Sang-Woo; Jung, Min; Chun, Yong-Min; Lee, Su-Keon; Jung, Woo Seok; Choi, Chong Hyuk; Kim, Sung-Jae; Kim, Sung-Hwan

2017-12-28

To analyze the effect of percutaneous pie-crusting medial release on valgus laxity before and after surgery and on clinical outcomes. Eight-hundred fourteen consecutive patients who underwent an arthroscopic procedure for the medial compartment of the knee were evaluated retrospectively. Sex, age, type of operation (meniscectomy, meniscal repair, and posterior root repair), type of accompanying surgery (none, cartilage procedure, ligament procedure and osteotomy) were documented. Sixty-four patients who underwent percutaneous pie-crusting medial release (release group) and 64 who did not undergo medial release (non-release group) were matched using the propensity score method. Each patient was evaluated for the following variables: degree of valgus laxity on stress radiographs, Lysholm knee score, visual analog scale score, and International Knee Documentation Committee knee score and grade. At the 24-month follow-up, no significant increase in side-to-side differences in the valgus gap was observed in comparison to the preoperative value in the release group [preoperative, - 0.1 ± 1.3 mm; follow-up, - 0.1 ± 1.4 mm; (n.s.)]. The follow-up Lysholm score, visual analog scale score and International Knee Documentation Committee knee score and grade were similar between the two groups. Percutaneous pie-crusting medial release is an additional procedure that can be performed during arthroscopic surgery for patients with a narrow medial joint space of the knee. Percutaneous pie-crusting medial release reduces iatrogenic injury to the cartilage and does not produce any residual valgus laxity of the knee. IV.

Persistent medial foot pain in an adolescent athlete.

PubMed

Hensley, Craig P; Reischl, Stephen F

2013-03-01

The patient was a 15-year-old adolescent male who was referred to a physical therapist for a chief complaint of worsening right medial foot pain. Given the worsening nature of the patient's right medial foot pain, palpatory findings, and a prior recommendation for computed tomography from a radiologist, the patient was referred to his physician. Subsequent computed tomography imaging of the right foot revealed a nondisplaced fracture through the dorsal-medial aspect of the navicular.

Cartilage Delamination Flap Mimicking a Torn Medial Meniscus

PubMed Central

Bin Abd Razak, Hamid Rahmatullah; Amit Kanta, Mitra

2016-01-01

We report a case of a chondral delamination lesion due to medial parapatellar plica friction syndrome involving the medial femoral condyle. This mimicked a torn medial meniscus in clinical and radiological presentation. Arthroscopy revealed a chondral delamination flap, which was debrided. Diagnosis of chondral lesions in the knee can be challenging. Clinical examination and MRI have good accuracy for diagnosis and should be used in tandem. Early diagnosis and treatment of chondral lesions are important to prevent progression to early osteoarthritis. PMID:28070434

Medial prefrontal-hippocampal connectivity during emotional memory encoding predicts individual differences in the loss of associative memory specificity.

PubMed

Berkers, Ruud M W J; Klumpers, Floris; Fernández, Guillén

2016-10-01

Emotionally charged items are often remembered better, whereas a paradoxical loss of specificity is found for associative emotional information (specific memory). The balance between specific and generalized emotional memories appears to show large individual differences, potentially related to differences in (the risk for) affective disorders that are characterized by 'overgeneralized' emotional memories. Here, we investigate the neural underpinnings of individual differences in emotional associative memory. A large group of healthy male participants were scanned while encoding associations of face-photographs and written occupational identities that were of either neutral ('driver') or negative ('murderer') valence. Subsequently, memory was tested by prompting participants to retrieve the occupational identities corresponding to each face. Whereas in both valence categories a similar amount of faces was labeled correctly with 'neutral' and 'negative' identities, (gist memory), specific associations were found to be less accurately remembered when the occupational identity was negative compared to neutral (specific memory). This pattern of results suggests reduced memory specificity for associations containing a negatively valenced component. The encoding of these negative associations was paired with a selective increase in medial prefrontal cortex activity and medial prefrontal-hippocampal connectivity. Individual differences in valence-specific neural connectivity were predictive of valence-specific reduction of memory specificity. The relationship between loss of emotional memory specificity and medial prefrontal-hippocampal connectivity is in line with the hypothesized role of a medial prefrontal-hippocampal circuit in regulating memory specificity, and warrants further investigations in individuals displaying 'overgeneralized' emotional memories. Copyright © 2016 Elsevier Inc. All rights reserved.

The medial prefrontal cortex and memory of cue location in the rat.

PubMed

Rawson, Tim; O'Kane, Michael; Talk, Andrew

2010-01-01

We developed a single-trial cue-location memory task in which rats experienced an auditory cue while exploring an environment. They then recalled and avoided the sound origination point after the cue was paired with shock in a separate context. Subjects with medial prefrontal cortical (mPFC) lesions made no such avoidance response, but both lesioned and control subjects avoided the cue itself when presented at test. A follow up assessment revealed no spatial learning impairment in either group. These findings suggest that the rodent mPFC is required for incidental learning or recollection of the location at which a discrete cue occurred, but is not required for cue recognition or for allocentric spatial memory. Copyright 2009 Elsevier Inc. All rights reserved.

Opening the medial tibiofemoral compartment by pie-crusting the superficial medial collateral ligament at its tibial insertion: a cadaver study.

PubMed

Roussignol, X; Gauthe, R; Rahali, S; Mandereau, C; Courage, O; Duparc, F

2015-09-01

Arthroscopic treatment of tears in the middle and posterior parts of the medial meniscus can be difficult when the medial tibiofemoral compartment is tight. Passage of the instruments may damage the cartilage. The primary objective of this cadaver study was to perform an arthroscopic evaluation of medial tibiofemoral compartment opening after pie-crusting release (PCR) of the superficial medial collateral ligament (sMCL) at its distal insertion on the tibia. The secondary objective was to describe the anatomic relationships at the site of PCR (saphenous nerve, medial saphenous vein). We studied 10 cadaver knees with no history of invasive procedures. The femur was held in a vise with the knee flexed at 45°, and the medial aspect of the knee was dissected. PCR of the sMCL was performed under arthroscopic vision, in the anteroposterior direction, at the distal tibial insertion of the sMCL, along the lower edge of the tibial insertion of the semi-tendinosus tendon. Continuous 300-N valgus stress was applied to the ankle. Opening of the medial tibiofemoral compartment was measured arthroscopically using graduated palpation hooks after sequential PCR of the sMCL. The compartment opened by 1mm after release of the anterior third, 2.3mm after release of the anterior two-thirds, and 3.9mm after subtotal release. A femoral fracture occurred in 1 case, after completion of all measurements. Both the saphenous nerve and the medial saphenous vein were located at a distance from the PCR site in all 10 knees. PCR of the sMCL is chiefly described as a ligament-balancing method during total knee arthroplasty. This procedure is usually performed at the joint line, where it opens the compartment by 4-6mm at the most, with some degree of unpredictability. PCR of the sMCL at its distal tibial insertion provides gradual opening of the compartment, to a maximum value similar to that obtained with PCR at the joint space. The lower edge of the semi-tendinosus tendon is a valuable landmark

Medial meniscus anatomy-from basic science to treatment.

PubMed

Śmigielski, Robert; Becker, Roland; Zdanowicz, Urszula; Ciszek, Bogdan

2015-01-01

This paper focuses on the anatomical attachment of the medial meniscus. Detailed anatomical dissections have been performed and illustrated. Five zones can be distinguished in regard to the meniscus attachments anatomy: zone 1 (of the anterior root), zone 2 (anteromedial zone), zone 3 (the medial zone), zone 4 (the posterior zone) and the zone 5 (of the posterior root). The understanding of the meniscal anatomy is especially crucial for meniscus repair but also for correct fixation of the anterior and posterior horn of the medial meniscus.

Anatomical medial surfaces with efficient resolution of branches singularities.

PubMed

Gil, Debora; Vera, Sergio; Borràs, Agnés; Andaluz, Albert; González Ballester, Miguel A

2017-01-01

Medial surfaces are powerful tools for shape description, but their use has been limited due to the sensibility of existing methods to branching artifacts. Medial branching artifacts are associated to perturbations of the object boundary rather than to geometric features. Such instability is a main obstacle for a confident application in shape recognition and description. Medial branches correspond to singularities of the medial surface and, thus, they are problematic for existing morphological and energy-based algorithms. In this paper, we use algebraic geometry concepts in an energy-based approach to compute a medial surface presenting a stable branching topology. We also present an efficient GPU-CPU implementation using standard image processing tools. We show the method computational efficiency and quality on a custom made synthetic database. Finally, we present some results on a medical imaging application for localization of abdominal pathologies. Copyright © 2016 Elsevier B.V. All rights reserved.

The pie-crusting technique using a blade knife for medial collateral ligament release is unreliable in varus total knee arthroplasty.

PubMed

Kwak, Dai-Soon; In, Yong; Kim, Tae Kyun; Cho, Han Suk; Koh, In Jun

2016-01-01

Despite the documented clinical efficacy of the pie-crusting technique for medial collateral ligament (MCL) release in varus total knee arthroplasty, its quantitative effects on medial gaps and safety remain unclear. This study was undertaken to determine the efficacy (quantitative effect and consistency of the number of punctures) and the safety (frequency of early over-release) of the pie-crusting technique for MCL release. From ten pairs of cadaveric knees, one knee from each pair was randomly assigned to undergo pie crusting in extension (group E) or in flexion (group F). Pie crusting was performed in the superficial MCL using a blade until over-release occurred. After every puncture, the incremental medial gap increase was recorded, and the number of punctures required for 2- or 4-mm gap increases was assessed. In group E, the extension gap increased from 0.8 to 5.0 mm and the flexion gap increased from 0.8 to 3.0 mm. In group F, the extension gap increased from 1.0 to 3.0 mm and the flexion gap increased from 2.6 to 6.0 mm. However, the gap increments were inconsistent with those that followed the preceding blade punctures, and the number of punctures required to increase the gaps by 2 or 4 mm was variable. The number of punctures leading to over-release in group E and group F was 6 ± 1 and 3 ± 1 punctures, respectively. Overall, 70% of over-release occurred earlier than the average number of punctures leading to over-release. Pie crusting led to unpredictable gap increments and to frequent early over-release. Surgeons should decide carefully before using the pie-crusting technique for MCL release and should be cautious of performing throughout the procedure, especially when performing in a flexed knee. Therapeutic study, Level I.

Natural history of medial clavicle fractures.

PubMed

Salipas, Andrew; Kimmel, Lara A; Edwards, Elton R; Rakhra, Sandeep; Moaveni, Afshin Kamali

2016-10-01

Fractures of the medial third of the clavicle comprise less than 3% of all clavicle fractures. The natural history and optimal management of these rare injuries are unknown. The aim of our study is to describe the demographics, management and outcomes of patients with medial clavicle fractures treated at a Level 1 Trauma Centre. A retrospective review was conducted of patients presenting to our institution between January 2008 and March 2013 with a medial third clavicle fracture. Clinical and radiographic data were recorded including mechanism of injury, fracture pattern and displacement, associated injuries, management and complications. Functional outcomes were assessed using the Glasgow Outcome Scale Extended (GOS-E) scores from the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). Shoulder outcomes were assessed using two patient reported outcomes scores, the American Shoulder and Elbow Society Score (ASES) and the Subjective Shoulder Value (SSV). Sixty eight medial clavicle fractures in 68 patients were evaluated. The majority of patients were male (n=53), with a median age of 53.5 years (interquartile range (IQR) 37.5-74.5 years). The most common mechanism of injury was motor vehicle accident (n=28). The in-hospital mortality rate was 4.4%. The fracture pattern was almost equally distributed between extra articular (n=35) and intra-articular (n=33). Fifty-five fractures (80.9%) had minimal or no displacement. Associated injuries were predominantly thoracic (n=31). All fractures were initially managed non-operatively, with a broad arm sling. Delayed operative fixation was performed for painful atrophic delayed union in two patients (2.9%). Both patients were under 65 years of age and had a severely displaced fracture of the medial clavicle. One intra-operative vascular complication was seen, with no adverse long-term outcome. Follow-up was obtained in 85.0% of the surviving cohort at an average of three years post injury (range 1-6 years). The mean ASES

Auditory inhibitory gating in medial prefrontal cortex: Single unit and local field potential analysis.

PubMed

Mears, R P; Klein, A C; Cromwell, H C

2006-08-11

Medial prefrontal cortex is a crucial region involved in inhibitory processes. Damage to the medial prefrontal cortex can lead to loss of normal inhibitory control over motor, sensory, emotional and cognitive functions. The goal of the present study was to examine the basic properties of inhibitory gating in this brain region in rats. Inhibitory gating has recently been proposed as a neurophysiological assay for sensory filters in higher brain regions that potentially enable or disable information throughput. This perspective has important clinical relevance due to the findings that gating is dramatically impaired in individuals with emotional and cognitive impairments (i.e. schizophrenia). We used the standard inhibitory gating two-tone paradigm with a 500 ms interval between tones and a 10 s interval between tone pairs. We recorded both single unit and local field potentials from chronic microwire arrays implanted in the medial prefrontal cortex. We investigated short-term (within session) and long-term (between session) variability of auditory gating and additionally examined how altering the interval between the tones influenced the potency of the inhibition. The local field potentials displayed greater variability with a reduction in the amplitudes of the tone responses over both the short and long-term time windows. The decrease across sessions was most intense for the second tone response (test tone) leading to a more robust gating (lower T/C ratio). Surprisingly, single unit responses of different varieties retained similar levels of auditory responsiveness and inhibition in both the short and long-term analysis. Neural inhibition decreased monotonically related to the increase in intertone interval. This change in gating was most consistent in the local field potentials. Subsets of single unit responses did not show the lack of inhibition even for the longer intertone intervals tested (4 s interval). These findings support the idea that the medial

Categorization of biologically relevant chemical signals in the medial amygdala

PubMed Central

Samuelsen, Chad L.; Meredith, Michael

2009-01-01

Many species employ chemical signals to convey messages between members of the same species (conspecific), but chemosignals may also provide information to another species (heterospecific). Here, we found that conspecific chemosignals (male, female mouse urine) increased immediate early gene-protein (IEG) expression in both anterior and posterior medial amygdala of male mice, whereas most heterospecific chemosignals (e.g.: hamster vaginal fluid, steer urine) increased expression only in anterior medial amygdala. This categorization of responses in medial amygdala conforms to our previously reported findings in male hamsters. The same characteristic pattern of IEG expression appears in the medial amygdala of each species in response to conspecific stimuli for that species. These results suggest that the amygdala categorizes stimuli according to the biological relevance for the tested species. Thus, a heterospecific predator (cat collar) stimulus, which elicited behavioral avoidance in mice, increased IEG expression in mouse posterior medial amygdala (like conspecific stimuli). Further analysis suggests reproduction related and potentially threatening stimuli produce increased IEG expression in different sub-regions of posterior medial amygdala (dorsal and ventral, respectively). These patterns of IEG expression in medial amygdala may provide glimpses of a tertiary sorting of chemosensory signals beyond the primary-level selectivity of chemosensory neurons and the secondary sorting in main and accessory olfactory bulbs. PMID:19368822

Isolated medial medullary infarction due to vertebral artery dissection.

PubMed

Wakita, M; Matsuoka, H; Hamada, R; Kasuya, J; Osame, M

2003-12-01

A 54-year-old man developed left hemiparesis and tactile and deep sensory disturbance following onset of rightside cervical pain. These symptoms resulted from an isolated infarct in the right medial area of the upper medulla oblongata and intracranial vertebral artery (VA) dissection. Atherosclerotic disease of the VA is the most common cause of medial medullary infarction. In past reports of isolated medial medullary infarction, only a few cases involved VA dissection.

Medial temporal lobe contributions to cued retrieval of items and contexts.

PubMed

Hannula, Deborah E; Libby, Laura A; Yonelinas, Andrew P; Ranganath, Charan

2013-10-01

Several models have proposed that different regions of the medial temporal lobes contribute to different aspects of episodic memory. For instance, according to one view, the perirhinal cortex represents specific items, parahippocampal cortex represents information regarding the context in which these items were encountered, and the hippocampus represents item-context bindings. Here, we used event-related functional magnetic resonance imaging (fMRI) to test a specific prediction of this model-namely, that successful retrieval of items from context cues will elicit perirhinal recruitment and that successful retrieval of contexts from item cues will elicit parahippocampal cortex recruitment. Retrieval of the bound representation in either case was expected to elicit hippocampal engagement. To test these predictions, we had participants study several item-context pairs (i.e., pictures of objects and scenes, respectively), and then had them attempt to recall items from associated context cues and contexts from associated item cues during a scanned retrieval session. Results based on both univariate and multivariate analyses confirmed a role for hippocampus in content-general relational memory retrieval, and a role for parahippocampal cortex in successful retrieval of contexts from item cues. However, we also found that activity differences in perirhinal cortex were correlated with successful cued recall for both items and contexts. These findings provide partial support for the above predictions and are discussed with respect to several models of medial temporal lobe function. Copyright © 2013 Elsevier Ltd. All rights reserved.

Medial Temporal Lobe Contributions to Cued Retrieval of Items and Contexts

PubMed Central

Hannula, Deborah E.; Libby, Laura A.; Yonelinas, Andrew P.; Ranganath, Charan

2013-01-01

Several models have proposed that different regions of the medial temporal lobes contribute to different aspects of episodic memory. For instance, according to one view, the perirhinal cortex represents specific items, parahippocampal cortex represents information regarding the context in which these items were encountered, and the hippocampus represents item-context bindings. Here, we used event-related functional magnetic resonance imaging (fMRI) to test a specific prediction of this model – namely, that successful retrieval of items from context cues will elicit perirhinal recruitment and that successful retrieval of contexts from item cues will elicit parahippocampal cortex recruitment. Retrieval of the bound representation in either case was expected to elicit hippocampal engagement. To test these predictions, we had participants study several item-context pairs (i.e., pictures of objects and scenes, respectively), and then had them attempt to recall items from associated context cues and contexts from associated item cues during a scanned retrieval session. Results based on both univariate and multivariate analyses confirmed a role for hippocampus in content-general relational memory retrieval, and a role for parahippocampal cortex in successful retrieval of contexts from item cues. However, we also found that activity differences in perirhinal cortex were correlated with successful cued recall for both items and contexts. These findings provide partial support for the above predictions and are discussed with respect to several models of medial temporal lobe function. PMID:23466350

Medial vestibulospinal tract lesions impair sacculo-collic reflexes.

PubMed

Kim, Seonhye; Lee, Hak-Seung; Kim, Ji Soo

2010-05-01

The medial vestibulospinal tract (VST) is known to mediate the vestibular-evoked myogenic potential (VEMP) in the contracting sternocleidomastoid muscle (SCM). To determine whether disruption of the medial VST in the medulla impairs formation of VEMP, we measured VEMP in 14 patients with medial medullary infarction (MMI). VEMP was induced by a short tone burst and was recorded in contracting SCM while patients turned their heads forcefully to the contralateral side against resistance. Normative data were obtained from 47 healthy volunteers. Seven patients (50%) had abnormal VEMP in the side of the MMI lesion, absent in two, decreased in four, and delayed in two. One patient showed both decreased and delayed response. Of the seven patients with abnormal VEMP, five had the lesions that extended to the dorsal tegmentum while five of the seven patients with normal VEMP showed restricted anteromedial lesions mainly involving the pyramids. Spontaneous nystagmus (4/7, 57%), gaze-evoked nystagmus (6/7, 86%), and ocular tilt reaction/tilt of the subjective visual vertical (4/7, 57%) were frequently observed in the patients with abnormal VEMP. The abnormal VEMP in patients with infarctions involving the medullary tegmentum supports that VEMP is mediated by the medial VST descending within the medial longitudinal fasciculus.

Dendrites of medial olivocochlear neurons in mouse.

PubMed

Brown, M C; Levine, J L

2008-06-12

Stains for acetylcholinesterase (AChE) and retrograde labeling with Fluorogold (FG) were used to study olivocochlear neurons and their dendritic patterns in mice. The two methods gave similar results for location and number of somata. The total number of medial olivocochlear (MOC) neurons in the ventral nucleus of the trapezoid body (VNTB) is about 170 per side. An additional dozen large olivocochlear neurons are located in the dorsal periolivary nucleus (DPO). Dendrites of all of these neurons are long and extend in all directions from the cell bodies, a pattern that contrasts with the sharp frequency tuning of their responses. For VNTB neurons, there were greater numbers of dendrites directed medially than laterally and those directed medially were longer (on average, 25-50% longer). Dendrite extensions were most pronounced for neurons located in the rostral portion of the VNTB. When each dendrite from a single neuron was represented as a vector, and all the vectors summed, the result was also skewed toward the medial direction. DPO neurons, however, had more symmetric dendrites that projected into more dorsal parts of the trapezoid body, suggesting that this small group of olivocochlear neurons has very different physiological properties. Dendrites of both types of neurons were somewhat elongated rostrally, about 20% longer than those directed caudally. These results can be interpreted as extensions of dendrites of olivocochlear neurons toward their synaptic inputs: medially to meet crossing fibers from the cochlear nucleus that are part of the MOC reflex pathway, and rostrally to meet descending inputs from higher centers.

TCDD alters medial epithelial cell differentiation during palatogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbott, B.D.; Birnbaum, L.S.

1989-06-15

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widely distributed, persistent environmental contaminant that is teratogenic in mice, where it induces hydronephrosis and cleft palate. The incidence of clefting has been shown to be dose dependent after exposure on either gestation Day (GD) 10 or 12, although the embryo is more susceptible on GD 12. TCDD-exposed palatal shelves meet but do not fuse, and programmed cell death of the medial epithelial cells is inhibited. The mechanism of action through which TCDD alters the program of medial cell development has not been examined in earlier studies, and it is not known whether the mechanism ismore » the same regardless of the dose or developmental stage of exposure. In this study, C57BL/6N mice, a strain sensitive to TCDD, were dosed orally on GD 10 or 12 with 0, 6, 12, 24, or 30 micrograms/kg body wt, in 10 ml corn oil/kg. Embryonic palatal shelves were examined on GD 14, 15, or 16. The degree of palatal closure, epithelial surface morphology, and cellular ultrastructure, the incorporation of (3H)TdR, the expression of EGF receptors, and the binding of 125I-EGF were assessed. After exposure on GD 10 or 12, TCDD altered the differentiation pathway of the medial epithelial cells. The palatal shelves were of normal size and overall morphology, but fusion of the medial epithelia of the opposing shelves did not occur. TCDD prevented programmed cell death of the medial peridermal cells. The expression of EGF receptors by medial cells continued through Day 16 and the receptors were able to bind ligand. The medial cells differentiated into a stratified, squamous, keratinizing epithelium. The shift in phenotype to an oral-like epithelium occurred after exposure on either GD 10 or 12. At the lower dose (6 micrograms/kg), fewer cleft palates were produced, but those shelves which did respond had a fully expressed shift in differentiation.« less

The "safe zone" in medial percutaneous calcaneal pin placement.

PubMed

Gamie, Zakareya; Donnelly, Leo; Tsiridis, Eleftherios

2009-05-01

Percutaneous pin insertion into the medial calcaneus places a number of structures at risk. Evidence suggests that the greatest risk is to the medial calcaneal nerve (MCN). The medial calcaneal region of 24 cadavers was dissected to determine the major structures at risk. By using four palpable anatomical landmarks, the inferior tip of the medial malleolus (point A), the posterior superior portion of the calcaneal tuberosity (point B), the navicular tuberosity (point C), and the medial process of the calcaneal tuberosity (point D), we attempted to define the safe zone taking into account all possible variables in our dissections including ankle position, side, gender, and possible anatomical variations of the MCN. The commonest arrangement of the MCN was two MCNs that arose independently, one arising before the bifurcation of the tibial nerve and the other arising from the medial plantar nerve. A zone could be defined posterior to 75% of the distance along the lines AB, CD, AD, and CB which would avoid most structures. The posterior branches of the MCN, however, would still be at risk and placing the pin too far posteriorly risks an avulsion fracture. This is the first study to employ four palpable anatomical landmarks to identify a zone to minimize damage to neurovascular structures. It may not be possible, however, to avoid injury of the MCN and consequent sensory loss to the sole of the foot.

The measurement of medial knee gap width using ultrasound.

PubMed

Slane, Laura C; Slane, Josh A; Scheys, Lennart

2017-08-01

Medial knee instability is a key clinical parameter for assessing ligament injury and arthroplasty success, but current methods for measuring stability are typically either qualitative or involve ionizing radiation. The purpose of this study was to perform a preliminary analysis of whether ultrasound (US) could be used as an alternate approach for quantifying medial instability by comparing an US method with an approach mimicking the current gold standard fluoroscopy method. US data from the medial knee were collected, while cadaveric lower limbs (n = 8) were loaded in valgus (10 Nm). During post-processing, the US gap width was measured by identifying the medial edges of the femur and tibia and computing the gap width between these points. For comparison, mimicked fluoroscopy (mFluoro) images were created from specimen-specific bone models, developed from segmented CT scans, and from kinematic data collected during testing. Then, gap width was measured in the mFluoro images based on two different published approaches with gap width measured either at the most medial or at the most distal aspect of the femur. Gap width increased significantly with loading (p < 0.001), and there were no significant differences between the US method (unloaded: 8.7 ± 2.4 mm, loaded: 10.7 ± 2.2 mm) and the mFluoro method that measured gap width at the medial femur. In terms of the change in gap width with load, no correlation with the change in abduction angle was observed, with no correlation between the various methods. Inter-rater reliability for the US method was high (0.899-0.952). Ultrasound shows promise as a suitable alternative for quantifying medial instability without radiation exposure. However, the outstanding limitations of existing approaches and lack of true ground-truth data require that further validation work is necessary to better understand the clinical viability of an US approach for measuring medial knee gap width.

Posterior medial meniscus root ligament lesions: MRI classification and associated findings.

PubMed

Choi, Ja-Young; Chang, Eric Y; Cunha, Guilherme M; Tafur, Monica; Statum, Sheronda; Chung, Christine B

2014-12-01

The purposes of this study were to determine the prevalence of altered MRI appearances of "posterior medial meniscus root ligament (PMMRL)" lesions, introduce a classification of lesion types, and report associated findings. We retrospectively reviewed 419 knee MRI studies to identify the presence of PMMRL lesions. Classification was established on the basis of lesions encountered. The medial compartment was assessed for medial meniscal tears in the meniscus proper, medial meniscal extrusion, insertional PMMRL osseous changes, regional synovitis, osteoarthritis, insufficiency fracture, and cruciate ligament abnormality. PMMRL abnormalities occurred in 28.6% (120/419) of the studies: degeneration, 14.3% (60/419) and tear, 14.3% (60/419). Our classification system included degeneration and tearing. Tearing was categorized as partial or complete with delineation of the point of failure as entheseal, midsubstance, or junction to meniscus. Of all tears, 93.3% (56/60) occurred at the meniscal junction. Univariate analysis revealed significant differences between the knees with and without PMMRL lesions in age, medial meniscal tear, medial meniscal extrusion, insertional PMMRL osseous change, regional synovitis, osteoarthritis, insufficiency fracture (p=0.017), and cruciate ligament degeneration (p<0.001). PMMRL lesions are commonly detected in symptomatic patients. We have introduced an MRI classification system. PMMRL lesions are significantly associated with age, medial meniscal tears, medial meniscal extrusion, insertional PMMRL osseous change, regional synovitis, osteoarthritis, insufficiency fracture, and cruciate ligament degeneration.

Episodic snapping of the medial head of the triceps due to weightlifting.

PubMed

Spinner, R J; Wenger, D E; Barry, C J; Goldner, R D

1999-01-01

We describe two patients who had episodic elbow snapping and ulnar nerve dysesthesias only after weightlifting. These symptoms would disappear soon afterward. The episodic nature of their complaints and findings led to misdiagnosis. We documented by repeated clinical examinations and magnetic resonance imaging that the presence of these symptoms correlated directly with the finding of intermittent, activity-related snapping of the medial triceps. In both patients, the symptoms disappeared when the medial portion of the triceps migrated medially but did not dislocate over the medial epicondyle with elbow flexion. Thus, a minor change in the configuration of the medial portion of the triceps (fluid accumulation) in the same individual at different times can cause intermittent dislocation of the medial triceps. Previous papers dealing with patients with snapping of the medial triceps describe symptoms exacerbated by athletic activities, but the constant finding of snapping on sequential examinations.

Effect of Medial Patellofemoral Ligament Reconstruction Method on Patellofemoral Contact Pressures and Kinematics.

PubMed

Stephen, Joanna M; Kittl, Christoph; Williams, Andy; Zaffagnini, Stefano; Marcheggiani Muccioli, Giulio Maria; Fink, Christian; Amis, Andrew A

2016-05-01

There remains a lack of evidence regarding the optimal method when reconstructing the medial patellofemoral ligament (MPFL) and whether some graft constructs can be more forgiving to surgical errors, such as overtensioning or tunnel malpositioning, than others. The null hypothesis was that there would not be a significant difference between reconstruction methods (eg, graft type and fixation) in the adverse biomechanical effects (eg, patellar maltracking or elevated articular contact pressure) resulting from surgical errors such as tunnel malpositioning or graft overtensioning. Controlled laboratory study. Nine fresh-frozen cadaveric knees were placed on a customized testing rig, where the femur was fixed but the tibia could be moved freely from 0° to 90° of flexion. Individual quadriceps heads and the iliotibial tract were separated and loaded to 205 N of tension using a weighted pulley system. Patellofemoral contact pressures and patellar tracking were measured at 0°, 10°, 20°, 30°, 60°, and 90° of flexion using pressure-sensitive film inserted between the patella and trochlea, in conjunction with an optical tracking system. The MPFL was transected and then reconstructed in a randomized order using a (1) double-strand gracilis tendon, (2) quadriceps tendon, and (3) tensor fasciae latae allograft. Pressure maps and tracking measurements were recorded for each reconstruction method in 2 N and 10 N of tension and with the graft positioned in the anatomic, proximal, and distal femoral tunnel positions. Statistical analysis was undertaken using repeated-measures analyses of variance, Bonferroni post hoc analyses, and paired t tests. Anatomically placed grafts during MPFL reconstruction tensioned to 2 N resulted in the restoration of intact medial joint contact pressures and patellar tracking for all 3 graft types investigated (P > .050). However, femoral tunnels positioned proximal or distal to the anatomic origin resulted in significant increases in the mean

Medial Auditory Thalamus Inactivation Prevents Acquisition and Retention of Eyeblink Conditioning

ERIC Educational Resources Information Center

Halverson, Hunter E.; Poremba, Amy; Freeman, John H.

2008-01-01

The auditory conditioned stimulus (CS) pathway that is necessary for delay eyeblink conditioning was investigated using reversible inactivation of the medial auditory thalamic nuclei (MATN) consisting of the medial division of the medial geniculate (MGm), suprageniculate (SG), and posterior intralaminar nucleus (PIN). Rats were given saline or…

The medial patellofemoral complex.

PubMed

Loeb, Alexander E; Tanaka, Miho J

2018-06-01

The purpose of this review is to describe the current understanding of the medial patellofemoral complex, including recent anatomic advances, evaluation of indications for reconstruction with concomitant pathology, and surgical reconstruction techniques. Recent advances in our understanding of MPFC anatomy have found that there are fibers that insert onto the deep quadriceps tendon as well as the patella, thus earning the name "medial patellofemoral complex" to allow for the variability in its anatomy. In MPFC reconstruction, anatomic origin and insertion points and appropriate graft length are critical to prevent overconstraint of the patellofemoral joint. The MPFC is a crucial soft tissue checkrein to lateral patellar translation, and its repair or reconstruction results in good restoration of patellofemoral stability. As our understanding of MPFC anatomy evolves, further studies are needed to apply its relevance in kinematics and surgical applications to its role in maintaining patellar stability.

Results of step-cut medial malleolar osteotomy.

PubMed

Thordarson, David B; Kaku, Shawn K

2006-12-01

Treatment of certain complex ankle pathology, such as a talar body fracture or osteochondral lesion requiring grafting, can necessitate medial malleolar osteotomy for adequate operative exposure. This paper evaluates the step-cut medial malleolar osteotomy for exposure of the ankle joint. Fourteen patients with intra-articular pathology, including talar body fractures or osteochondral lesions necessitating extensive intra-articular exposure had step-cut malleolar osteotomy. The average age of the patients was 37 (range 20-90) years, and the average followup was 8 months. All 14 patients had an uncomplicated intraoperative course, with excellent exposure of the ankle joint. All patients had prompt healing of the osteotomy by 6 weeks after surgery without loss of reduction. None of the patients had pain at the osteotomy site. Step-cut medial malleolar osteotomy is an excellent, reproducible method for extensive exposure of the talar dome.

Neuromuscular Characteristics of Individuals Displaying Excessive Medial Knee Displacement

PubMed Central

Padua, Darin A.; Bell, David R.; Clark, Micheal A.

2012-01-01

Context Knee-valgus motion is a potential risk factor for certain lower extremity injuries, including anterior cruciate ligament injury and patellofemoral pain. Identifying neuromuscular characteristics associated with knee-valgus motion, such as hip and lower leg muscle activation, may improve our ability to prevent lower extremity injuries. Objective We hypothesized that hip and lower leg muscle-activation amplitude would differ among individuals displaying knee valgus (medial knee displacement) during a double-legged squat compared with those who did not display knee valgus. We further suggested that the use of a heel lift would alter lower leg muscle activation and frontal-plane knee motion in those demonstrating medial knee displacement. Design Descriptive laboratory study. Setting Research laboratory. Patients or Other Participants A total of 37 healthy participants were assigned to the control (n = 19) or medial-knee-displacement (n = 18) group based on their double-legged squat performance. Main Outcome Measure(s) Muscle-activation amplitude for the gluteus maximus, gluteus medius, adductor magnus, medial and lateral gastrocnemius, and tibialis anterior was measured during 2 double-legged squat tasks. The first task consisted of performing a double-legged squat without a heel lift; the second consisted of performing a double-legged squat task with a 2-in (5.08-cm) lift under the heels. Results Muscle-activation amplitude for the hip adductor, gastrocnemius, and tibialis anterior was greater in those who displayed knee valgus than in those who did not (P < .05). Also, use of heel lifts resulted in decreased activation of the gluteus maximus, hip adductor, gastrocnemius, and tibialis anterior muscles (P < .05). Use of heel lifts also eliminated medially directed frontal-plane knee motion in those displaying medial knee displacement. Conclusions Medial knee displacement during squatting tasks appears to be associated with increased hip-adductor activation and

Medialization thyroplasty versus injection laryngoplasty: a cost minimization analysis.

PubMed

Tam, Samantha; Sun, Hongmei; Sarma, Sisira; Siu, Jennifer; Fung, Kevin; Sowerby, Leigh

2017-02-20

Medialization thyroplasty and injection laryngoplasty are widely accepted treatment options for unilateral vocal fold paralysis. Although both procedures result in similar clinical outcomes, little is known about the corresponding medical care costs. Medialization thyroplasty requires expensive operating room resources while injection laryngoplasty utilizes outpatient resources but may require repeated procedures. The purpose of this study, therefore, is to quantify the cost differences in adult patients with unilateral vocal fold paralysis undergoing medialization thyroplasty versus injection laryngoplasty. Cost minimization analysis conducted using a decision tree model. A decision tree model was constructed to capture clinical scenarios for medialization thyroplasty and injection laryngoplasty. Probabilities for various events were obtained from a retrospective cohort from the London Health Sciences Centre, Canada. Costs were derived from the published literature and the London Health Science Centre. All costs were reported in 2014 Canadian dollars. Time horizon was 5 years. The study was conducted from an academic hospital perspective in Canada. Various sensitivity analyses were conducted to assess differences in procedure-specific costs and probabilities of key events. Sixty-three patients underwent medialization thyroplasty and 41 underwent injection laryngoplasty. Cost of medialization thyroplasty was C$2499.10 per patient whereas those treated with injection laryngoplasty cost C$943.19. Results showed that cost savings with IL were C$1555.91. Deterministic and probabilistic sensitivity analyses suggested cost savings ranged from C$596 to C$3626. Treatment with injection laryngoplasty results in cost savings of C$1555.91 per patient. Our extensive sensitivity analyses suggest that switching from medialization thyroplasty to injection laryngoplasty will lead to a minimum cost savings of C$596 per patient. Considering the significant cost savings and similar

Postero-medial approach for complex tibial plateau injuries with a postero-medial or postero-lateral shear fragment.

PubMed

Berber, Reshid; Lewis, Charlotte P; Copas, David; Forward, Daren P; Moran, Christopher G

2014-04-01

This study demonstrates the utility of a modified postero-medial surgical approach to the knee in treating a series of patients with complex tibial plateau injuries with associated postero-medial and postero-lateral shear fractures. Posterior coronal shear fractures are underappreciated and their clinical relevance has recently been characterised. Less-invasive surgery and indirect reduction techniques are inadequate for treating these coronal plane fractures. Our approach includes an inverted 'L'-shaped incision situated within the posterior flexor knee crease, followed by the retraction or incision of the medial head of the gastrocnemius tendon, while protecting the neurovascular structures. This provides a more extensile exposure, as far as the postero-lateral corner, than previously described. Our case series included eight females and eight males. The average age was 53 years. The majority of these injuries were sustained through high-energy trauma. All patients' fractures were classified as Schatzker grade 4, or above, with a postero-medial split depression. Eight patients had associated postero-lateral corner fractures. Two were open, two had vascular compromise and one had neurological injury. The average time to surgery was 6.4 days (range 0-12), operative time 142 min (range 76-300) and length of stay 17 days (range 7-46). A total of 11 patients were treated using the postero-medial approach alone and in five the treatment was combined with an antero-lateral approach. Two patients suffered a reduced range of movement requiring manipulation and physiotherapy, and three patients had a 5-degree fixed flexion deformity. Two patients developed superficial wound infections treated with antibiotics alone. Anatomical reduction and fracture union was achieved in 15 patients. These are complex fractures to treat, and our modified posterior approach allows direct reduction and optimal positioning of plates to act as buttress devices. It can be extended across the

Resection of Grade III cranial horn tears of the equine medial meniscus alter the contact forces on medial tibial condyle at full extension: an in-vitro cadaveric study.

PubMed

Fowlie, Jennifer; Arnoczky, Steven; Lavagnino, Michael; Maerz, Tristan; Stick, John

2011-12-01

To evaluate the magnitude and distribution of joint contact pressure on the medial tibial condyle after grade III cranial horn tears of the medial meniscus. Experimental study. Cadaveric equine stifles (n = 6). Cadaveric stifles were mounted in a materials testing system and electronic pressure sensors were placed between the medial tibial condyle and medial meniscus. Specimens were loaded parallel to the longitudinal axis of the tibia to 1800 N at 130°, 140°, 150°, and 160° stifle angle. Peak pressure and contact area were recorded from the contact maps. Testing was repeated after surgical creation of a grade III cranial horn tear of the medial meniscus, and after resection of the simulated tear. In the intact specimens, a significantly smaller contact area was observed at 160° compared with the other angles (P < .05). Creation of a grade III cranial horn tear in the medial meniscus did not significantly alter the pressure or contact area measurements at any stifle angle compared with intact specimens (P > .05). Resection of the tear resulted in significantly higher peak pressures in the central region of the medial tibial condyle at a stifle angle of 160° relative to the intact (P = .026) and torn (P = .012) specimens. Resection of grade III cranial horn tears in the medial meniscus resulted in a central focal region of increased pressure on the medial tibial condyle at 160° stifle angle. © Copyright 2011 by The American College of Veterinary Surgeons.

Clinical study of medial area infarction in the region of posterior inferior cerebellar artery.

PubMed

Ogawa, Katsuhiko; Suzuki, Yutaka; Oishi, Minoru; Kamei, Satoshi; Shigihara, Shuntaro; Nomura, Yasuyuki

2013-05-01

Our objective is to study the neurological characteristics of medial area infarction in the caudal cerebellum. Medial area of the caudal cerebellum is supplied with 2 branches of the posterior inferior cerebellar artery (PICA). The medial hemispheric branch of the PICA distributes to the medial area of the caudal cerebellar hemisphere. The medial branch of the PICA (mPICA) distributes to the inferior vermis. We studied the neurological characteristics of 18 patients with medial area infarction of the caudal cerebellum. The infarction was located in the medial area of the cerebellar hemisphere and vermis (medial ch/vermis) in 11 patients and in the medial area of the cerebellar hemisphere (medial ch) in 7 patients. All the 18 patients showed acute vertigo and disturbance of standing and gait at onset. On admission, the lateropulsion and wide-based gait were present in 13 patients, respectively. Mild ataxia of the extremities was shown in 7 patients. Acute vertigo and unsteadiness were prominent at onset in the 18 patients, although their ataxia of the extremities was mild or none. This result was consistent with the characteristics of medial area infarction of the caudal cerebellum. Comparing the neurological symptoms between the medial ch/vermis group and medial ch group, both lateropulsion and wide-based gait were significantly infrequent in medial ch group. This result indicated that the vermis was spared because the mPICA was not involved in the medial ch group. It is necessary to make a careful diagnosis when we encounter patients who present acute vertigo because truncal and gait ataxia are unremarkable on admission in patients with the medial area infarction of the caudal cerebellum without vermis involvement. Published by Elsevier Inc.

The effects of neuromuscular exercise on medial knee joint load post-arthroscopic partial medial meniscectomy: 'SCOPEX', a randomised control trial protocol.

PubMed

Hall, Michelle; Hinman, Rana S; Wrigley, Tim V; Roos, Ewa M; Hodges, Paul W; Staples, Margaret; Bennell, Kim L

2012-11-27

Meniscectomy is a risk factor for knee osteoarthritis, with increased medial joint loading a likely contributor to the development and progression of knee osteoarthritis in this group. Therefore, post-surgical rehabilitation or interventions that reduce medial knee joint loading have the potential to reduce the risk of developing or progressing osteoarthritis. The primary purpose of this randomised, assessor-blind controlled trial is to determine the effects of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee joint load during functional tasks in people who have recently undergone a partial medial meniscectomy. 62 people aged 30-50 years who have undergone an arthroscopic partial medial meniscectomy within the previous 3 to 12 months will be recruited and randomly assigned to a neuromuscular exercise or control group using concealed allocation. The neuromuscular exercise group will attend 8 supervised exercise sessions with a physiotherapist and will perform 6 exercises at home, at least 3 times per week for 12 weeks. The control group will not receive the neuromuscular training program. Blinded assessment will be performed at baseline and immediately following the 12-week intervention. The primary outcomes are change in the peak external knee adduction moment measured by 3-dimensional analysis during normal paced walking and one-leg rise. Secondary outcomes include the change in peak external knee adduction moment during fast pace walking and one-leg hop and change in the knee adduction moment impulse during walking, one-leg rise and one-leg hop, knee and hip muscle strength, electromyographic muscle activation patterns, objective measures of physical function, as well as self-reported measures of physical function and symptoms and additional biomechanical parameters. The findings from this trial will provide evidence regarding the effect of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee

A clinical evaluation of alternative fixation techniques for medial malleolus fractures.

PubMed

Barnes, Hayley; Cannada, Lisa K; Watson, J Tracy

2014-09-01

Medial malleolus fractures have traditionally been managed using partially threaded screws and/or Kirschner wire fixation. Using these conventional techniques, a non-union rate of as high as 20% has been reported. In addition too many patients complaining of prominent hardware as a source of pain post-fixation. This study was designed to assess the outcomes of medial malleolar fixation using a headless compression screw in terms of union rate, the need for hardware removal, and pain over the hardware site. Saint Louis University and Mercy Medical Center, Level 1 Trauma Centers, St. Louis, MO. After IRB approval, we used billing records to identify all patients with ankle fractures involving the medial malleolus. Medical records and radiographs were reviewed to identify patients with medial malleolar fractures treated with headless compression screw fixation. Our inclusion criteria included follow-up until full weight bearing and a healed fracture. Follow-up clinical records and radiographs were reviewed to determine union, complication rate and perception of pain over the site of medial malleolus fixation. Sixty-four ankles were fixed via headless compression screws and 44 had adequate follow-up for additional evaluation. Seven patients had isolated medial malleolar fractures, 23 patients had bimalleolar fractures, and 14 patients had trimalleolar fractures. One patient (2%) required hardware removal due to cellulitis. One patient (2%) had a delayed union, which healed without additional intervention. Ten patients (23%) reported mild discomfort to palpation over the medial malleolus. The median follow-up was 35 weeks (range: 12-208 weeks). There were no screw removals for painful hardware and no cases of non-union. Headless compression screws provide effective compression of medial malleolus fractures and result in good clinical outcomes. The headless compression screw is a beneficial alternative to the conventional methods of medial malleolus fixation. Copyright �

Transcaruncular Approach for Treatment of Medial Wall and Large Orbital Blowout Fractures.

PubMed

Nguyen, Dennis C; Shahzad, Farooq; Snyder-Warwick, Alison; Patel, Kamlesh B; Woo, Albert S

2016-03-01

We evaluate the safety and efficacy of the transcaruncular approach for reconstruction of medial orbital wall fractures and the combined transcaruncular-transconjunctival approach for reconstruction of large orbital defects involving the medial wall and floor. A retrospective review of the clinical and radiographic data of patients who underwent either a transcaruncular or a combined transcaruncular-transconjunctival approach by a single surgeon for orbital fractures between June 2007 and June 2013 was undertaken. Seven patients with isolated medial wall fractures underwent a transcaruncular approach, and nine patients with combined medial wall and floor fractures underwent a transcaruncular-transconjunctival approach with a lateral canthotomy. Reconstruction was performed using a porous polyethylene implant. All patients with isolated medial wall fractures presented with enophthalmos. In the combined medial wall and floor group, five out of eight patients had enophthalmos with two also demonstrating hypoglobus. The size of the medial wall defect on preoperative computed tomography (CT) scan ranged from 2.6 to 4.6 cm(2); the defect size of combined medial wall and floor fractures was 4.5 to 12.7 cm(2). Of the 11 patients in whom postoperative CT scans were obtained, all were noted to have acceptable placement of the implant. All patients had correction of enophthalmos and hypoglobus. One complication was noted, with a retrobulbar hematoma having developed 2 days postoperatively. The transcaruncular approach is a safe and effective method for reconstruction of medial orbital floor fractures. Even large fractures involving the orbital medial wall and floor can be adequately exposed and reconstructed with a combined transcaruncular-transconjunctival-lateral canthotomy approach. The level of evidence of this study is IV (case series with pre/posttest).

Double PCL sign does not always indicate a bucket-handle tear of medial meniscus.

PubMed

Liu, Chen; Zheng, Hua Yong; Huang, Yan; Li, Hai Peng; Wu, Han; Sun, Tian Sheng; Yao, Jian Hua

2016-09-01

The discoid medial meniscus is an extremely rare anomaly. Bilateral discoid medial menisci are much more rare but intermittently reported. We report the first case of bilateral discoid medial menisci with positive double PCL sign, which typically indicates a bucket-handle tear of medial meniscus. A literature review was also conducted on bilateral discoid medial menisci.

[Application of pie-crusting the medial collateral ligament release in arthroscopic surgery for posterior horn of 
medial meniscus in knee joint].

PubMed

Zhu, Weihong; Tang, Qi; Liao, Lele; Li, Ding; Yang, Yang; Chen, You

2017-09-28

To explore the effectiveness and safety of pie-crusting the medial collateral ligament release (MCL) in treating posterior horn of medial meniscus (PHMM) tear in tight medial tibiofemoral compartment of knee joint.
 Methods: Thirty-two consecutive patients with PHMM tear in tight medial tibiofemoral compartment of knee joint were admitted to our department from January, 2013 to December, 2014. All patients were performed pie-crusting the MCL release at its tibial insertion with 18-gauge intravenous needle. All patients were evaluated by valgus stress test and bilateral valgus stress radiograph at postoperative 1st day, 4th week and 12th week. Visual Analogue Scales (VAS), Lysholm scores, Tegner scores and International Knee Documentation Committee (IKDC) scores were recorded at the 1st, 3th, 6th month follow-up, then follow-up every 6 months.
 Results: The mean follow-up was 28 (24-36) months. All cases were negative in valgus stress test. MCL rupture, femoral fracture, articular cartilage lesion and neurovascular injury were not found at the last follow-up. The median medial joint space width of affected side and unaffected side for valgus stress radiographs were 6.8 mm and 4.3 mm (P<0.05) at the 1st day, 5.5 mm and 4.2 mm 
(P<0.05) in the 4th week and 4.8 mm and 4.3 mm (P>0.05) at the 12th week, respectively. VAS scores was changed from 4.5±1.5 preoperatively to 1.7±1.0 at the final follow-up (t=16.561, P<0.05). Lysholm scores was changed from 52.3±5.8 preoperatively to 93.2±6.3 at the final follow-up (t=-41.353, P<0.05). Tegner scores was changed from 4.1±1.1 preoperatively to 5.5±0.6 at the final follow-up (t=-18.792, P<0.05). IKDC scores was changed from 54.5±6.2 preoperative to 93.8±4.5 at the final follow-up (t=-38.253, P<0.05).
 Conclusion: Pie-crusting the medial collateral ligament release is a safe, minimal invasive and effective surgical option for posterior horn of medial meniscus tear in tight medial tibiofemoral compartment of knee

Dysphagia in a patient with bilateral medial medullary infarcts.

PubMed

Paliwal, Vimal K; Kalita, Jayanti; Misra, Usha K

2009-09-01

Bilateral medial medullary infarct is a rare stroke syndrome and only a handful of cases have been described. Dysphagia as a manifestation of medullary infarcts is well recognized but often associated with lateral medullary infarct. Bilateral medial medullary infarcts are commonly associated with severe dysphagia in addition to a number of other signs and symptoms. We describe a patient who had bilateral medial medullary infarct with severe dysphagia in addition to quadriplegia and respiratory difficulty, and analyze infarct topography with respect to dysphagia, risk factors, vascular territories involved, and prognosis in view of previously reported cases.

Modified tension band wiring of medial malleolar ankle fractures.

PubMed

Georgiadis, G M; White, D B

1995-02-01

Twenty-two displaced medial malleolar ankle fractures that were treated surgically using the modified tension band method of Cleak and Dawson were retrospectively reviewed at an average follow-up of 25 months. The technique involves the use of a screw to anchor a figure-of-eight wire. There were no malreductions and all fractures healed. Problems with the technique included technical errors with hardware placement, medial ankle pain, and asymptomatic wire migration. Despite this, modified tension band wiring remains an acceptable method for fixation of selected displaced medial malleolar fractures. It is especially suited for small fracture fragments and osteoporotic bone.

The medial tibial stress syndrome. A cause of shin splints.

PubMed

Mubarak, S J; Gould, R N; Lee, Y F; Schmidt, D A; Hargens, A R

1982-01-01

The medial tibial stress syndrome is a symptom complex seen in athletes who complain of exercise-induced pain along the distal posterior-medial aspect of the tibia. Intramuscular pressures within the posterior compartments of the leg were measured in 12 patients with this disorder. These pressures were not elevated and therefore this syndrome is a not a compartment syndrome. Available information suggests that the medial tibial stress syndrome most likely represents a periostitis at this location of the leg.

Ultrastructure of medial rectus muscles in patients with intermittent exotropia.

PubMed

Yao, J; Wang, X; Ren, H; Liu, G; Lu, P

2016-01-01

PURPOSE To study the ultrastructure of the medial rectus in patients with intermittent exotropia at different ages.PATIENTS AND METHODS The medial recti were harvested surgically from 20 patients with intermittent exotropia. Patients were divided into adolescent (age<18 years, n=10) and adult groups (age >18 years, n=10). The normal control group included five patients without strabismus and undergoing eye enucleation. Hematoxylin and eosin staining and transmission electron microscopy were used to visualize the medial recti. Western blot was used to determine the levels of myosin and actin.RESULTS Varying fiber thickness, atrophy, and misalignment of the medial recti were visualized under optical microscope in patients with exotropia. Electron microscopy revealed sarcomere destruction, myofilament disintegration, unclear dark and light bands, collagen proliferation, and fibrosis. The adolescent group manifested significantly higher levels of myosin and actin than the adult group (P<0.05).CONCLUSION Younger patients with intermittent exotropia show stronger contraction of the medial recti compared with older patients. Our findings suggest that childhood was the appropriate time for surgery as the benefit of the intervention was better than in adulthood.

Effects of active feedback gait retraining to produce a medial weight transfer at the foot in subjects with symptomatic medial knee osteoarthritis.

PubMed

Erhart-Hledik, Jennifer C; Asay, Jessica L; Clancy, Caitlin; Chu, Constance R; Andriacchi, Thomas P

2017-10-01

This study aimed to determine if active feedback gait retraining to produce a medial weight transfer at the foot significantly reduces the knee adduction moment in subjects with medial compartment knee osteoarthritis. Secondarily, changes in peak knee flexion moment, frontal plane knee and ankle kinematics, and center of pressure were investigated. Ten individuals with medial compartment knee osteoarthritis (9 males; age: 65.3 ± 9.8 years; BMI: 27.8 ± 3.0 kg/m 2 ) were tested at self-selected normal and fast speeds in two conditions: Intervention, with an active feedback device attached to the shoe of their more affected leg, and control, with the device de-activated. Kinematics and kinetics were assessed using a motion capture system and force plate. The first peak, second peak, and impulse of the knee adduction moment were significantly reduced by 6.0%, 13.9%, and 9.2%, respectively, at normal speed, with reductions of 10.7% and 8.6% in first peak and impulse at fast speed, respectively, with the active feedback system, with no significant effect on the peak knee flexion moment. Significant reductions in peak varus knee angle and medialized center of pressure in the first half of stance were observed, with reductions in peak varus knee angle associated with reductions in the knee adduction moment. This study demonstrated that active feedback to produce a medial weight-bearing shift at the foot reduces the peaks and impulse of the knee adduction moment in patients with medial compartment knee osteoarthritis. Future research should determine the long-term effect of the active feedback intervention on joint loading, pain, and function. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2251-2259, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Changes in articular cartilage following arthroscopic partial medial meniscectomy.

PubMed

Eichinger, Martin; Schocke, Michael; Hoser, Christian; Fink, Christian; Mayr, Raul; Rosenberger, Ralf E

2016-05-01

To examine degenerative changes in all cartilage surfaces of the knee following arthroscopic partial medial meniscectomy. For this prospective cohort study, 14 patients (five female) with a mean age of 47.9 ± 12.9 years who had undergone isolated arthroscopic partial medial meniscectomy were evaluated. Cartilage-sensitive magnetic resonance imaging (MRI) scans were acquired from the operated knees before the index operations, as well as at 6, 12, and 24 months after surgery. The MRI scans were assessed for the prevalence, severity, and size of cartilage degenerations. The clinical outcome was assessed using the SF-36 physical and mental component score and the International Knee Documentation Committee Knee Evaluation Form and was correlated with radiological findings. There was a significant increase in the severity of cartilage lesions in the medial tibial plateau (P = 0.019), as well as a trend towards an increase in the lateral tibial plateau. The size of the cartilage lesions increased significantly in the medial femoral condyle (P = 0.005) and lateral femoral condyle (P = 0.029), as well as in the patella (P = 0.019). Functional outcome scores improved significantly throughout the follow-up period. There was no correlation between cartilage wear and functional outcome. Arthroscopic partial medial meniscectomy is associated with adverse effects on articular cartilage and may lead to an increase in the severity and size of cartilage lesions. Post-operative cartilage wear predominantly affected the medial compartment and also affected the other compartments of the knee. Strategies to reduce subsequent osteoarthritic changes need to involve all compartments of the knee. IV.

The effects of neuromuscular exercise on medial knee joint load post-arthroscopic partial medial meniscectomy: ‘SCOPEX’ a randomised control trial protocol

PubMed Central

2012-01-01

Background Meniscectomy is a risk factor for knee osteoarthritis, with increased medial joint loading a likely contributor to the development and progression of knee osteoarthritis in this group. Therefore, post-surgical rehabilitation or interventions that reduce medial knee joint loading have the potential to reduce the risk of developing or progressing osteoarthritis. The primary purpose of this randomised, assessor-blind controlled trial is to determine the effects of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee joint load during functional tasks in people who have recently undergone a partial medial meniscectomy. Methods/design 62 people aged 30–50 years who have undergone an arthroscopic partial medial meniscectomy within the previous 3 to 12 months will be recruited and randomly assigned to a neuromuscular exercise or control group using concealed allocation. The neuromuscular exercise group will attend 8 supervised exercise sessions with a physiotherapist and will perform 6 exercises at home, at least 3 times per week for 12 weeks. The control group will not receive the neuromuscular training program. Blinded assessment will be performed at baseline and immediately following the 12-week intervention. The primary outcomes are change in the peak external knee adduction moment measured by 3-dimensional analysis during normal paced walking and one-leg rise. Secondary outcomes include the change in peak external knee adduction moment during fast pace walking and one-leg hop and change in the knee adduction moment impulse during walking, one-leg rise and one-leg hop, knee and hip muscle strength, electromyographic muscle activation patterns, objective measures of physical function, as well as self-reported measures of physical function and symptoms and additional biomechanical parameters. Discussion The findings from this trial will provide evidence regarding the effect of a home-based, physiotherapist

Common medial frontal mechanisms of adaptive control in humans and rodents

PubMed Central

Frank, Michael J.; Laubach, Mark

2013-01-01

In this report, we describe how common brain networks within the medial frontal cortex facilitate adaptive behavioral control in rodents and humans. We demonstrate that low frequency oscillations below 12 Hz are dramatically modulated after errors in humans over mid-frontal cortex and in rats within prelimbic and anterior cingulate regions of medial frontal cortex. These oscillations were phase-locked between medial frontal cortex and motor areas in both rats and humans. In rats, single neurons that encoded prior behavioral outcomes were phase-coherent with low-frequency field oscillations particularly after errors. Inactivating medial frontal regions in rats led to impaired behavioral adjustments after errors, eliminated the differential expression of low frequency oscillations after errors, and increased low-frequency spike-field coupling within motor cortex. Our results describe a novel mechanism for behavioral adaptation via low-frequency oscillations and elucidate how medial frontal networks synchronize brain activity to guide performance. PMID:24141310

Symptomatic Bilateral Torn Discoid Medial Meniscus Treated with Saucerization and Suture

PubMed Central

2016-01-01

Discoid meniscus is an anatomical congenital anomaly more often found in the lateral meniscus. A discoid medial meniscus is a very rare anomaly, and even more rare is to diagnose a bilateral discoid medial meniscus although the real prevalence of this situation is unknown because not all the discoid medial menisci are symptomatic and if the contralateral knee is not symptomatic then it is not usually studied. The standard treatment of this kind of pathology is partial meniscectomy. Currently the tendency is to be very conservative so suture and saucerization of a torn discoid meniscus when possible are gaining support. We present the case of a 13-year-old patient who was diagnosed with symptomatic torn bilateral discoid medial meniscus treated by suturing the tear and saucerization. To the best of our knowledge this is the first case reported of bilateral torn discoid medial meniscus treated in this manner in the same patient. PMID:27656305

Etiology and Treatment of Delayed-Onset Medial Malleolar Pain Following Total Ankle Arthroplasty.

PubMed

Lundeen, Gregory A; Dunaway, Linda J

2016-08-01

Total ankle arthroplasty (TAA) has become a successful treatment for end-stage ankle arthritis. Some patients may still have pain or may present with new pain. Suggested sources of medial pain include tibialis posterior tendonitis, impingement, or medial malleolar stress fracture. Etiology and treatment remain unclear. The objective of our study was to evaluate patients with delayed-onset medial malleolar pain following TAA who underwent treatment with percutaneous medial malleolar screw placement and propose an etiology. Patients who had undergone TAA at our institution were reviewed and those with medial malleolar pain were identified. Clinical and radiographic examinations were performed pre- and postoperatively. Radiographs were compared with those from a cohort of controls without a history of medial pain. All affected patients failed conservative therapy and were treated with percutaneous placement of medial malleolar screws positioned from the malleolar tip and extending proximally beyond the tibial component. Postoperatively, patients were placed in an ace wrap and allowed to be weightbearing to tolerance, except for 1 patient initially restricted to partial weightbearing. Visual analog scale (VAS) scores were recorded. Seventy-four (74) patients underwent TAA by the corresponding author. All (100%) were female with an average age of 66 (range, 57-73) years. Average follow-up since screw placement was 21.4 (range, 10-41) months. Six (8.1%) underwent placement of 2 percutaneous medial malleolar screws. Patients presented with pain an average of 12 (range, 4-24) months postoperatively and underwent screw placement an average of 2.8 (range, 1-6) months after presentation. At the time of TAA, none had a coronal plane deformity and none underwent a deltoid ligament release as part of balancing. All (100%) patients had pain and swelling directly over the medial malleolus prior to screw placement. Postoperatively, 1 (17%) had mild pain clinically at this site and

Temporary Medial Upper Eyelid Lagophthalmos after External Dacryocystorhinostomy.

PubMed

Haefliger, I O; Meienberg, O; Pimentel de Figueiredo, A R

2016-04-01

Background. Report of three cases of medial upper eyelid lagophthalmos as complication of external dacryocystorhinostomy. History and Signs. Shortly after dacryocystorhinostomy (skin incision on the side of the nose), three of ten consecutive patients (28 ± 4 years; mean ± standard deviation), presented with an ipsilateral lagophthalmos of 4 ± 1 mm in voluntary eyelid closure and 6 ± 1 mm in spontaneous blink. The lagophthalmos was due to a selective paresis of the medial part of the orbicularis oculi muscle of the upper eyelid. Patient 1 complained bitterly of dry eye symptoms and of her lagophthalmos. Patient 2 had mild symptoms but became very concerned after peers made her aware of her asymmetric blink. Patient 3 was asymptomatic and did not notice anything particular. Therapy and Outcome. Lagophthalmos resolved spontaneously within three months after surgery, first by improvement of voluntary eyelid closure and then of spontaneous blinking. Conclusions. Temporary lagophthalmos can occur as a complication of external dacryocystorhinostomy, most likely due to damage of the (only recently described) superficial buccal and/or zygomatic branches of the facial nerve that run upward to cross over the medial ligament and innervate the medial part of the orbicularis oculi muscle. Georg Thieme Verlag KG Stuttgart · New York.

Medial malleolar stress fracture secondary to chronic ankle impingement.

PubMed

Jowett, Andrew J L; Birks, Christopher L; Blackney, Mark C

2008-07-01

Medial malleolar stress fractures are uncommon even in the sporting population. We believe that stress fractures of the medial malleolus may be the end stage of chronic anteromedial ankle impingement in elite running and jumping athletes. We present five cases of elite athletes who presented to our institution with stress fractures of the medial malleolus over a 3-year period (2004 to 2007). In each case preoperative imaging revealed an anteromedial bony spur on the tibia. All fractures were internally fixed and at the same sitting had arthroscopic debridement of the bony spur. All fractures united without further intervention, average time to union was 10.2 (range, 6 to 16) weeks. At most recent review (average, 18 months; range, 8 to 37 months), all patients had resumed sporting activity to their previous level. No patient had suffered a recurrent fracture of the medial malleolus. We believe this region of impingement to be important in the development of the stress fracture and should be addressed at the time of fracture fixation.

Perfusion network shift during seizures in medial temporal lobe epilepsy.

PubMed

Sequeira, Karen M; Tabesh, Ali; Sainju, Rup K; DeSantis, Stacia M; Naselaris, Thomas; Joseph, Jane E; Ahlman, Mark A; Spicer, Kenneth M; Glazier, Steve S; Edwards, Jonathan C; Bonilha, Leonardo

2013-01-01

Medial temporal lobe epilepsy (MTLE) is associated with limbic atrophy involving the hippocampus, peri-hippocampal and extra-temporal structures. While MTLE is related to static structural limbic compromise, it is unknown whether the limbic system undergoes dynamic regional perfusion network alterations during seizures. In this study, we aimed to investigate state specific (i.e. ictal versus interictal) perfusional limbic networks in patients with MTLE. We studied clinical information and single photon emission computed tomography (SPECT) images obtained with intravenous infusion of the radioactive tracer Technetium- Tc 99 m Hexamethylpropyleneamine Oxime (Tc-99 m HMPAO) during ictal and interictal state confirmed by video-electroencephalography (VEEG) in 20 patients with unilateral MTLE (12 left and 8 right MTLE). Pair-wise voxel-based analyses were used to define global changes in tracer between states. Regional tracer uptake was calculated and state specific adjacency matrices were constructed based on regional correlation of uptake across subjects. Graph theoretical measures were applied to investigate global and regional state specific network reconfigurations. A significant increase in tracer uptake was observed during the ictal state in the medial temporal region, cerebellum, thalamus, insula and putamen. From network analyses, we observed a relative decreased correlation between the epileptogenic temporal region and remaining cortex during the interictal state, followed by a surge of cross-correlated perfusion in epileptogenic temporal-limbic structures during a seizure, corresponding to local network integration. These results suggest that MTLE is associated with a state specific perfusion and possibly functional organization consisting of a surge of limbic cross-correlated tracer uptake during a seizure, with a relative disconnection of the epileptogenic temporal lobe in the interictal period. This pattern of state specific shift in metabolic networks in

Temporal characteristics of Punjabi word-medial singletons and geminates.

PubMed

Hussain, Qandeel

2015-10-01

Many studies have investigated the temporal characteristics of the word-medial singletons and geminates in Indo-Aryan languages. However, little is known about the acoustic cues distinguishing between the word-medial singletons and geminates of Punjabi. The present study examines the temporal characteristics of Punjabi word-medial singleton and geminate stops in a C1V1C2V2 template. The results from five Punjabi speakers showed that, unlike previous studies of Indo-Aryan languages, the durations of C2 and V2 are the most important acoustic correlates of singleton and geminate stops in Punjabi. These findings therefore point towards the cross-linguistic differences in the acoustic correlates of singletons and geminates.

Endoscopic partial medial maxillectomy with mucosal flap for maxillary sinus mucoceles.

PubMed

Durr, Megan L; Goldberg, Andrew N

2014-01-01

To describe a technique of endoscopic medial maxillectomy with mucosal flap for postoperative maxillary sinus mucoceles and to present a case series of subjects who underwent this procedure. This case series includes four subjects with postoperative maxillary sinus mucoceles who underwent resection via endoscopic partial medial maxillectomy with a mucosal flap. We will discuss the clinical presentation, imaging characteristics, operative details, and outcomes. Four subjects are included in this study. The average age at the time of medial maxillectomy was 52 years (range 35-65 years). Three subjects (75%) were female. One subject (25%) had bilateral postoperative maxillary sinus mucoceles. Two subjects (50%) had unilateral right sided mucoceles, and the remaining subject had a unilateral left sided mucocele. All subjects had a history of multiple sinus procedures for chronic sinusitis including Caldwell-Luc procedures ipsilateral to the postoperative mucocele. All subjects underwent endoscopic medial maxillectomy without complication and were symptom free at the last follow up appointment, average 24 months (range 3-71 months) after medial maxillectomy. For postoperative maxillary sinus mucoceles in locations that are difficult to access via the middle meatus antrostomy, we recommend endoscopic medial maxillectomy with mucosal flap. Our preliminary experience with four subjects demonstrates complete resolution of symptoms after this procedure. Copyright © 2014 Elsevier Inc. All rights reserved.

Increased expression of c-fos in the medial preoptic area after mating in male rats: role of afferent inputs from the medial amygdala and midbrain central tegmental field.

PubMed

Baum, M J; Everitt, B J

1992-10-01

Immunocytochemical methods were used to localize the protein product of the immediate-early gene, c-fos, in male rats after exposure to, or direct physical interaction with, oestrous females. Increasing amounts of physical contact with a female, with resultant olfactory-vomeronasal and/or genital-somatosensory inputs, caused corresponding increments in c-fos expression in the medial preoptic area, the caudal part of the bed nucleus of the stria terminalis, the medial amygdala, and the midbrain central tegmental field. Males bearing unilateral electrothermal lesions of the olfactory peduncle showed a significant reduction in c-fos expression in the ipsilateral medial amygdala, but not in other structures, provided their coital interaction with oestrous females was restricted to mount-thrust and occasional intromissive patterns due to repeated application of lidocaine anaesthetic to the penis. No such lateralization of c-fos expression occurred in other males with unilateral olfactory lesions which were allowed to intromit and ejaculate with a female. These results suggest that olfactory inputs, possibly of vomeronasal origin, contribute to the activation of c-fos in the medial amygdala. However, lesion-induced deficits in this type of afferent input to the nervous system appear to be readily compensated for by the genital somatosensory input derived from repeated intromissions. Unilateral excitotoxic lesions of the medial preoptic area, made by infusing quinolinic acid, failed to reduce c-fos expression in the ipsilateral or contralateral medial amygdala or central tegmental field following ejaculation. By contrast, combined, unilateral excitotoxic lesions of the medial amygdala and the central tegmental field significantly reduced c-fos expression in the ipsilateral bed nucleus of the stria terminalis and medial preoptic area after mating; no such asymmetry in c-fos expression occurred when lesions were restricted to either the medial amygdala or central tegmental

Anatomical analysis of medial branches of dorsal rami of cervical nerves for radiofrequency thermocoagulation.

PubMed

Kweon, Tae Dong; Kim, Ji Young; Lee, Hye Yeon; Kim, Myung Hwa; Lee, Youn-Woo

2014-01-01

Cervical medial branch blocks are used to treat patients with chronic neck pain. The aim of this study was to clarify the anatomical aspects of the cervical medial branches to improve the accuracy and safety of radiofrequency denervation. Twenty cervical specimens were harvested from 20 adult cadavers. The anatomical parameters of the C4-C7 cervical medial branches were measured. The 3-dimensional computed tomography reconstruction images of the bone were also analyzed. Based on cadaveric analysis, most of the cervical dorsal rami gave off 1 medial branch; however, the cervical dorsal rami gave off 2 medial branches in 27%, 15%, 2%, and 0% at the vertebral level C4, C5, C6, and C7, respectively. The diameters of the medial branches varied from 1.0 to 1.2 mm, and the average distance from the notch of inferior articular process to the medial branches was about 2 mm. Most of the bifurcation sites were located at the medial side of the posterior tubercle of the transverse process. On the analysis of 3-dimensional computed tomography reconstruction images, cervical medial branches (C4 to C6) passed through the upper 49% to 53% of a line between the tips of 2 consecutive superior articular processes (anterior line). Also, cervical medial branches passed through the upper 28% to 35% of a line between the midpoints of 2 consecutive facet joints (midline). The present anatomical study may help improve accuracy and safety during radiofrequency denervation of the cervical medial branches.

Systematic review of medial versus lateral survivorship in unicompartmental knee arthroplasty.

PubMed

van der List, J P; McDonald, L S; Pearle, A D

2015-12-01

Unicompartmental knee arthroplasty (UKA) has gained popularity in patients with isolated unicompartmental osteoarthritis. To our knowledge no systematic review has assessed and compared survivorship of medial and lateral UKA. We performed a systematic review assessing medial and lateral UKA survivorship and comparing survivorship in cohort studies and registry-based studies. A search was performed using PubMed, Embase and Cochrane systems. Ninety-six eligible studies reported survivorship, of which fifty-eight reported medial and sixteen reported lateral UKA survivorship. Nineteen cohort studies and seven registry-based studies reported combined medial and lateral survivorship. The five-year, ten-year and fifteen-year medial UKA survivorship was 93.9%, 91.7% and 88.9%, respectively. Lateral UKA survivorship was 93.2%, 91.4% and 89.4% at five-year, ten-year and fifteen-year, respectively. No statistical difference between both compartments was found. At twenty years and twenty-five years survivorship of medial UKA was 84.7% and 80%, respectively, but no studies reported lateral UKA survivorship at these follow-up intervals. Survivorship of cohort studies was not significantly higher compared to registry-based studies at five years (94.3 vs. 91.7, respectively, p=0.133) but was significantly higher at ten years (90.5 vs. 84.1, p=0.015). This is the first systematic review that shows no difference in the five-, ten- and fifteen-year survivorship of medial and lateral UKA. We found a lower survivorship in the registry-based studies compared to cohort studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Morphometry of medial gaps of human brain artery branches.

PubMed

Canham, Peter B; Finlay, Helen M

2004-05-01

The bifurcation regions of the major human cerebral arteries are vulnerable to the formation of saccular aneurysms. A consistent feature of these bifurcations is a discontinuity of the tunica media at the apex of the flow divider. The objective was to measure the 3-dimensional geometry of these medial gaps or "medial defects." Nineteen bifurcations and 2 junctions of human cerebral arteries branches (from 4 male and 2 female subjects) were formalin-fixed at physiological pressure and processed for longitudinal serial sectioning. The apex and adjacent regions were examined and measurements were made from high-magnification photomicrographs, or projection microscope images, of the gap dimensions at multiple levels through the bifurcation. Plots were made of the width of the media as a function of distance from the apex. The media at each edge of the medial gap widened over a short distance, reaching the full width of the media of the contiguous daughter vessel. Medial gap dimensions were compared with the planar angle of the bifurcation, and a strong negative correlation was found, ie, the acute angled branches have the more prominent medial gaps. A discontinuity of the media at the apex was seen in all the bifurcations examined and was also found in the junction regions of brain arteries. We determined that the gap width is continuous with well-defined dimensions throughout its length and average length-to-width ratio of 6.9. The gaps were generally centered on the prominence of the apical ridge.

Association of medial meniscal extrusion with medial tibial osteophyte distance detected by T2 mapping MRI in patients with early-stage knee osteoarthritis.

PubMed

Hada, Shinnosuke; Ishijima, Muneaki; Kaneko, Haruka; Kinoshita, Mayuko; Liu, Lizu; Sadatsuki, Ryo; Futami, Ippei; Yusup, Anwajan; Takamura, Tomohiro; Arita, Hitoshi; Shiozawa, Jun; Aoki, Takako; Takazawa, Yuji; Ikeda, Hiroshi; Aoki, Shigeki; Kurosawa, Hisashi; Okada, Yasunori; Kaneko, Kazuo

2017-09-12

Medial meniscal extrusion (MME) is associated with progression of medial knee osteoarthritis (OA), but no or little information is available for relationships between MME and osteophytes, which are found in cartilage and bone parts. Because of the limitation in detectability of the cartilage part of osteophytes by radiography or conventional magnetic resonance imaging (MRI), the rate of development and size of osteophytes appear to have been underestimated. Because T2 mapping MRI may enable us to evaluate the cartilage part of osteophytes, we aimed to examine the association between MME and OA-related changes, including osteophytes, by using conventional and T2 mapping MRI. Patients with early-stage knee OA (n = 50) were examined. MRI-detected OA-related changes, in addition to MME, were evaluated according to the Whole-Organ Magnetic Resonance Imaging Score. T2 values of the medial meniscus and osteophytes were measured on T2 mapping images. Osteophytes surgically removed from patients with end-stage knee OA were histologically analyzed and compared with findings derived by radiography and MRI. Medial side osteophytes were detected by T2 mapping MRI in 98% of patients with early-stage knee OA, although the detection rate was 48% by conventional MRI and 40% by radiography. Among the OA-related changes, medial tibial osteophyte distance was most closely associated with MME, as determined by multiple logistic regression analysis, in the patients with early-stage knee OA (β = 0.711, p < 0.001). T2 values of the medial meniscus were directly correlated with MME in patients with early-stage knee OA, who showed ≥ 3 mm of MME (r = 0.58, p = 0.003). The accuracy of osteophyte evaluation by T2 mapping MRI was confirmed by histological analysis of the osteophytes removed from patients with end-stage knee OA. Our study demonstrates that medial tibial osteophyte evaluated by T2 mapping MRI is frequently observed in the patients with early-stage knee

Medial tibial pain. A prospective study of its cause among military recruits.

PubMed

Milgrom, C; Giladi, M; Stein, M; Kashtan, H; Margulies, J; Chisin, R; Steinberg, R; Swissa, A; Aharonson, Z

1986-12-01

In a prospective study of 295 infantry recruits during 14 weeks of basic training, 41% had medial tibial pain. Routine scintigraphic evaluation in cases of medial tibial bone pain showed that 63% had abnormalities. A stress fracture was found in 46%. Only two patients had periostitis. None had ischemic medial compartment syndrome. Physical examination could not differentiate between cases with medial tibial bone pain secondary to stress fractures and those with scintigraphically normal tibias. When both pain and swelling were localized in the middle one-third of the tibia, the lesion most likely proved to be a stress fracture.

Comparative techniques of medial rectus muscle retraction for endoscopic exposure of the medial intraconal space.

PubMed

Lin, Giant C; Freitag, Suzanne K; Kocharyan, Armine; Yoon, Michael K; Lefebvre, Daniel R; Bleier, Benjamin S

2016-05-01

The medial rectus muscle (MRM) is the medial boundary to the intraconal space of the orbit, and retraction of the MRM is oftentimes necessary for endoscopic removal of intraconal tumors, e.g., orbital hemangioma. We evaluated each of the reported methods of MRM retraction for endoscopic orbital surgery and quantified the degree of intraconal exposure conferred by each method. Eight orbits from four cadaver heads were dissected. In each orbit, medial orbital decompression was performed and the MRM was retracted by using four previously described techniques: (1) external MRM retraction at the globe insertion point by using vessel loop (external group), (2) transseptal MRM retraction by using vessel loop (transseptal group), (3) transchoanal retraction of the MRM by using vessel loop (choanal group), and (4) transseptal four-handed technique by using double ball retraction by a second surgeon (transseptal double ball group). The length, height, and area of exposure of the medial intraconal space were quantified and compared. The average ± standard deviation (SD) anterior-posterior exposures for the external group, transseptal group, and transseptal double ball group were 17.51 ± 3.39 mm, 16.59 ± 4.16 mm, and 18.0 ± 15.25 mm, respectively. The choanal group provided significantly less exposure (12.39 ± 3.44 mm, p = 0.049) than the other groups. The average ± SD vertical exposures for the transseptal group, choanal group, and transseptal double ball group were 12.53 ± 4.38 mm, 13.05 ± 5.86 mm, and 13.57 ± 3.74 mm, respectively. The external group provided significantly less exposure (4.51 ± 1.56 mm, p = 0.0072) than the other groups. The transseptal and transseptal double ball groups provided the greatest total access by surface area (58.88 ± 26.96 mm(2) and 62.94 ± 34.74 mm(2), respectively) compared with the external and choanal groups (34.82 ± 23.37 mm(2) and 43.10 ± 23.68 mm(2), respectively). Although the transseptal trajectory of MRM retraction was

Medial Meniscal Extrusion Relates to Cartilage Loss in Specific Femorotibial Subregions- Data from the Osteoarthritis Initiative

PubMed Central

Bloecker, K.; Wirth, W.; Guermazi, A.; Hunter, DJ; Resch, H.; Hochreiter, J.; Eckstein, F.

2015-01-01

Objective Medial meniscal extrusion is known to be related to structural progression of knee OA. However, it is unclear whether medial meniscal extrusion is more strongly associated with cartilage loss in certain medial femorotibial subregions than to others. Methods Segmentation of the medial tibial and femoral cartilage (baseline; 1-year follow-up) and the medial meniscus (baseline) was performed in 60 participants with frequent knee pain (age 61.3±9.2y, BMI 31.3±3.9 kg/m2) and with unilateral medial radiographic joint space narrowing (JSN) grade 1–3, using double echo steady state MR-images. Medial meniscal extrusion distance and extrusion area (%) between the external meniscal and tibial margin at baseline, and longitudinal medial cartilage loss in eight anatomical subregions were determined. Results A significant association (Pearson correlation coefficient) was seen between medial meniscus extrusion area in JSN knees and cartilage loss over one year throughout the entire medial femorotibial compartment. The strongest correlation was with cartilage loss in the external medial tibia (r=−0.34 [p<0.01] in JSN, and r=−0.30 [p=0.02] in noJSN knees). Conclusion Medial meniscus extrusion was associated with subsequent medial cartilage loss. The external medial tibial cartilage may be particularly vulnerable to thinning once the meniscus extrudes and its surface is “exposed” to direct, non-physiological, cartilage-cartilage contact. PMID:25988986

Pseudoaneurysm of the medial superior genicular artery after arthroscopic partial meniscectomy.

PubMed

Lee, Kee Byoung; Song, Si Young; Kwon, Duck Joo; Shin, Jun; Paik, Sang Hoon

2009-09-01

We describe a case of 43-year-old man who had a pseudoaneurysm of the medial superior genicular artery after arthroscopic partial meniscectomy with standard anterolateral and anteromedial portals. Pseudoaneurysm of the medial superior genicular artery has been reported at the previous superomedial portal site after arthroscopy. Described herein is a unique case that involved the medial superior genicular artery at the previous anteromedial portal site after arthroscopy. The pseudoaneurysm was successfully treated with transcatheter embolization.

Pseudoaneurysm of the Medial Superior Genicular Artery after Arthroscopic Partial Meniscectomy

PubMed Central

Lee, Kee Byoung; Kwon, Duck Joo; Shin, Jun; Paik, Sang Hoon

2009-01-01

We describe a case of 43-year-old man who had a pseudoaneurysm of the medial superior genicular artery after arthroscopic partial meniscectomy with standard anterolateral and anteromedial portals. Pseudoaneurysm of the medial superior genicular artery has been reported at the previous superomedial portal site after arthroscopy. Described herein is a unique case that involved the medial superior genicular artery at the previous anteromedial portal site after arthroscopy. The pseudoaneurysm was successfully treated with transcatheter embolization. PMID:19885054

Dissociating medial frontal and posterior cingulate activity during self-reflection.

PubMed

Johnson, Marcia K; Raye, Carol L; Mitchell, Karen J; Touryan, Sharon R; Greene, Erich J; Nolen-Hoeksema, Susan

2006-06-01

Motivationally significant agendas guide perception, thought and behaviour, helping one to define a 'self' and to regulate interactions with the environment. To investigate neural correlates of thinking about such agendas, we asked participants to think about their hopes and aspirations (promotion focus) or their duties and obligations (prevention focus) during functional magnetic resonance imaging and compared these self-reflection conditions with a distraction condition in which participants thought about non-self-relevant items. Self-reflection resulted in greater activity than distraction in dorsomedial frontal/anterior cingulate cortex and posterior cingulate cortex/precuneus, consistent with previous findings of activity in these areas during self-relevant thought. For additional medial areas, we report new evidence of a double dissociation of function between medial prefrontal/anterior cingulate cortex, which showed relatively greater activity to thinking about hopes and aspirations, and posterior cingulate cortex/precuneus, which showed relatively greater activity to thinking about duties and obligations. One possibility is that activity in medial prefrontal cortex is associated with instrumental or agentic self-reflection, whereas posterior medial cortex is associated with experiential self-reflection. Another, not necessarily mutually exclusive, possibility is that medial prefrontal cortex is associated with a more inward-directed focus, while posterior cingulate is associated with a more outward-directed, social or contextual focus.

Dissociating medial frontal and posterior cingulate activity during self-reflection

PubMed Central

Johnson, Marcia K.; Raye, Carol L.; Mitchell, Karen J.; Touryan, Sharon R.; Greene, Erich J.; Nolen-Hoeksema, Susan

2006-01-01

Motivationally significant agendas guide perception, thought and behaviour, helping one to define a ‘self’ and to regulate interactions with the environment. To investigate neural correlates of thinking about such agendas, we asked participants to think about their hopes and aspirations (promotion focus) or their duties and obligations (prevention focus) during functional magnetic resonance imaging and compared these self-reflection conditions with a distraction condition in which participants thought about non-self-relevant items. Self-reflection resulted in greater activity than distraction in dorsomedial frontal/anterior cingulate cortex and posterior cingulate cortex/precuneus, consistent with previous findings of activity in these areas during self-relevant thought. For additional medial areas, we report new evidence of a double dissociation of function between medial prefrontal/anterior cingulate cortex, which showed relatively greater activity to thinking about hopes and aspirations, and posterior cingulate cortex/precuneus, which showed relatively greater activity to thinking about duties and obligations. One possibility is that activity in medial prefrontal cortex is associated with instrumental or agentic self-reflection, whereas posterior medial cortex is associated with experiential self-reflection. Another, not necessarily mutually exclusive, possibility is that medial prefrontal cortex is associated with a more inward-directed focus, while posterior cingulate is associated with a more outward-directed, social or contextual focus. PMID:18574518

The "moving valgus stress test" for medial collateral ligament tears of the elbow.

PubMed

O'Driscoll, Shawn W M; Lawton, Richard L; Smith, Adam M

2005-02-01

The diagnosis of a painful partial tear of the medial collateral ligament in overhead-throwing athletes is challenging, even for experienced elbow surgeons and despite the use of sophisticated imaging techniques. The "moving valgus stress test" is an accurate physical examination technique for diagnosis of medial collateral ligament attenuation in the elbow. Cohort study (diagnosis); Level of evidence, 2. Twenty-one patients underwent surgical intervention for medial elbow pain due to medial collateral ligament insufficiency or other abnormality of chronic valgus overload, and they were assessed preoperatively with an examination called the moving valgus stress test. To perform the moving valgus stress test, the examiner applies and maintains a constant moderate valgus torque to the fully flexed elbow and then quickly extends the elbow. The test is positive if the medial elbow pain is reproduced at the medial collateral ligament and is at maximum between 120 degrees and 70 degrees. The moving valgus stress test was highly sensitive (100%, 17 of 17 patients) and specific (75%, 3 of 4 patients) when compared to assessment of the medial collateral ligament by surgical exploration or arthroscopic valgus stress testing. The mean shear range (ie, the arc within which pain was produced with the moving valgus stress test) was 120 degrees to 70 degrees. The mean angle at which pain was at a maximum was 90 degrees of elbow flexion. The moving valgus stress test is an accurate physical examination technique that, when performed and interpreted correctly, is highly sensitive for medial elbow pain arising from the medial collateral ligament.

Fiber Tracts of the Medial and Inferior Surfaces of the Cerebrum.

PubMed

Baydin, Serhat; Gungor, Abuzer; Tanriover, Necmettin; Baran, Oguz; Middlebrooks, Erik H; Rhoton, Albert L

2017-02-01

Fiber dissection studies of the cerebrum have focused on the lateral surface. No comparable detailed studies have been done on the medial and inferior surfaces. The object of this study was to examine the fiber tracts, cortical, and subcortical structures of the medial and inferior aspects of the brain important in planning operative approaches along the interhemispheric fissure, parafalcine area, and basal surfaces of the cerebrum. Twenty formalin-fixed human hemispheres (10 brains) were examined by fiber dissection technique under ×6-×40 magnifications. The superior longitudinal fasciculus I, cingulum, inferior longitudinal fasciculus, uncinate fasciculus, optic radiations, tapetum, and callosal fibers were dissected step by step from medial to lateral, exposing the nucleus accumbens, subthalamic nucleus, red nucleus, and central midline structures (fornix, stria medullaris, and stria terminalis). Finally, the central core structures were dissected from medial to lateral. Understanding the fiber network underlying the medial and inferior aspects of the brain is important in surgical planning for approaches along the interhemispheric fissure, parafalcine area, and basal surfaces of the cerebrum. Copyright © 2016. Published by Elsevier Inc.

Coordinated dysregulation of mRNAs and microRNAs in the rat medial prefrontal cortex following a history of alcohol dependence

PubMed Central

Tapocik, Jenica D.; Solomon, Matthew; Flanigan, Meghan; Meinhardt, Marcus; Barbier, Estelle; Schank, Jesse; Schwandt, Melanie; Sommer, Wolfgang H.; Heilig, Markus

2012-01-01

Long-term changes in brain gene expression have been identified in alcohol dependence, but underlying mechanisms remain unknown. Here, we examined the potential role of microRNAs for persistent gene expression changes in the rat medial prefrontal cortex after a history of alcohol dependence. Two-bottle free-choice alcohol consumption increased following 7-week exposure to intermittent alcohol intoxication. A bioinformatic approach using microarray analysis, qPCR, bioinformatic analysis, and microRNA-mRNA integrative analysis identified expression patterns indicative of a disruption in synaptic processes and neuroplasticity. 41 rat-microRNAs and 165 mRNAs in the medial prefrontal cortex were significantly altered after chronic alcohol exposure. A subset of the microRNAs and mRNAs was confirmed by qPCR. Gene ontology categories of differential expression pointed to functional processes commonly associated with neurotransmission, neuroadaptation, and synaptic plasticity. microRNA-mRNA expression pairing identified 33 microRNAs putatively targeting 89 mRNAs suggesting transcriptional networks involved in axonal guidance and neurotransmitter signaling. Our results demonstrate a significant shift in microRNA expression patterns in the medial prefrontal cortex following a history of dependence. Due to their global regulation of multiple downstream target transcripts, microRNAs may play a pivotal role in the reorganization of synaptic connections and long term neuroadaptations in alcohol dependence. microRNA-mediated alterations of transcriptional networks may be involved in disrupted prefrontal control over alcohol-drinking observed in alcoholic patients. PMID:22614244

Pediatric obesity and walking duration increase medial tibiofemoral compartment contact forces.

PubMed

Lerner, Zachary F; Board, Wayne J; Browning, Raymond C

2016-01-01

With the high prevalence of pediatric obesity there is a need for structured physical activity during childhood. However, altered tibiofemoral loading during physical activity in obese children likely contribute to their increased risk of orthopedic disorders of the knee. The goal of this study was to determine the effects of pediatric obesity and walking duration on medial and lateral tibiofemoral contact forces. We collected experimental biomechanics data during treadmill walking at 1 m•s(-1) for 20 min in 10 obese and 10 healthy-weight 8-12 year-olds. We created subject-specific musculoskeletal models using radiographic measures of tibiofemoral alignment and centers-of-pressure, and predicted medial and lateral tibiofemoral contact forces at the beginning and end of each trial. Obesity and walking duration affected tibiofemoral loading. At the beginning of the trail, the average percent of the total load passing through the medial compartment during stance was 85% in the obese children and 63% in the healthy-weight children; at the end of the trial, the medial distribution was 90% in the obese children and 72% in the healthy-weight children. Medial compartment loading rates were 1.78 times greater in the obese participants. The medial compartment loading rate increased 17% in both groups at the end compared to the beginning of the trial (p = 0.001). We found a strong linear relationship between body-fat percentage and the medial-lateral load distribution (r(2) = 0.79). Altered tibiofemoral loading during walking in obese children may contribute to their increased risk of knee pain and pathology. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Electrophysiological evidence during episodic prospection implicates medial prefrontal and bilateral middle temporal gyrus.

PubMed

Hsu, Chia-Fen; Sonuga-Barke, Edmund J S

2016-08-01

fMRI studies have implicated the medial prefrontal cortex and medial temporal lobe, components of the default mode network (DMN), in episodic prospection. This study compared quantitative EEG localized to these DMN regions during prospection and during resting and while waiting for rewards. EEG was recorded in twenty-two adults while they were asked to (i) envision future monetary episodes; (ii) wait for rewards and (iii) rest. Activation sources were localized to core DMN regions. EEG power and phase coherence were compared across conditions. Prospection, compared to resting and waiting, was associated with reduced power in the medial prefrontal gyrus and increased power in the bilateral medial temporal gyrus across frequency bands as well as greater phase synchrony between these regions in the delta band. The current quantitative EEG analysis confirms prior fMRI research suggesting that medial prefrontal and medial temporal gyrus interactions are central to the capacity for episodic prospection. Copyright © 2016 Elsevier B.V. All rights reserved.

Inverted distal clavicle anatomic locking plate for displaced medial clavicle fracture.

PubMed

Wang, Yong; Jiang, Jiannong; Dou, Bin; Zhang, Panjun

2015-09-01

Fractures of the medial clavicle are rare injuries. Recently, open reduction and internal fixation has been recommended for displaced medial clavicle fractures in order to prevent non-union and dysfunction. Because of the rarity of this injury, the optimal fixation device has not yet been established. In this report, we describe a case of a 40-year-old male patient who sustained a significantly displaced medial clavicle fracture treated by open reduction and internal fixation using an inverted distal clavicle anatomic locking plate. At the 12 months follow-up, the patient recovered well, had returned to pre-injury job, and was quite satisfied with the outcome. Internal fixation of medial clavicle fracture using an inverted distal clavicle anatomic locking plate of the ipsilateral side appears to be a good treatment option.

Decreased knee adduction moment does not guarantee decreased medial contact force during gait.

PubMed

Walter, Jonathan P; D'Lima, Darryl D; Colwell, Clifford W; Fregly, Benjamin J

2010-10-01

Excessive contact force is believed to contribute to the development of medial compartment knee osteoarthritis. The external knee adduction moment (KAM) has been identified as a surrogate measure for medial contact force during gait, with an abnormally large peak value being linked to increased pain and rate of disease progression. This study used in vivo gait data collected from a subject with a force-measuring knee implant to assess whether KAM decreases accurately predict corresponding decreases in medial contact force. Changes in both quantities generated via gait modification were analyzed statistically relative to the subject's normal gait. The two gait modifications were a "medial thrust" gait involving knee medialization during stance phase and a "walking pole" gait involving use of bilateral walking poles. Reductions in the first (largest) peak of the KAM (32-33%) did not correspond to reductions in the first peak of the medial contact force. In contrast, reductions in the second peak and angular impulse of the KAM (15-47%) corresponded to reductions in the second peak and impulse of the medial contact force (12-42%). Calculated reductions in both KAM peaks were highly sensitive to rotation of the shank reference frame about the superior-inferior axis of the shank. Both peaks of medial contact force were best predicted by a combination of peak values of the external KAM and peak absolute values of the external knee flexion moment (R(2) = 0.93). Future studies that evaluate the effectiveness of gait modifications for offloading the medial compartment of the knee should consider the combined effect of these two knee moments. Published by Wiley Periodicals, Inc. J Orthop Res 28:1348-1354, 2010.

A combinatorial optogenetic approach to medial habenula function

NASA Astrophysics Data System (ADS)

Turner, Eric E.; Hsu, Yun-Wei; Wang, Si; Morton, Glenn; Zeng, Hongkui

2013-03-01

The habenula is a brain region found in all vertebrate species. It consists of medial and lateral subnuclei which make complex descending connections to the brainstem. Although the medial habenula (MHb) and its projection, the fasciculus retroflexus (FR), have been recognized for decades, their function remains obscure. The small size of the MHb in rodents, and the cellular and molecular complexity of this region, have made it difficult to study the function of this region with high specificity. Here we describe a Cre-mediated genetic system for expressing the microbial opsin channelrhodopsin (ChR2) specifically in the dorsal (dMHb) and ventral (vMHb) medial habenula. Genetically targeted expression of ChR2 allows MHb neurons to be selectively activated with light in acute brain slices with electrophysiological readouts, and in vivo by means of custom-built fiber optic cannulas. These tools will allow highly specific studies of MHb circuitry and the role of the MHb in behaviors related to addiction and mood regulation.

Volition and conflict in human medial frontal cortex.

PubMed

Nachev, Parashkev; Rees, Geraint; Parton, Andrew; Kennard, Christopher; Husain, Masud

2005-01-26

Controversy surrounds the role of human medial frontal cortex in controlling actions. Although damage to this area leads to severe difficulties in spontaneously initiating actions, the precise mechanisms underlying such "volitional" deficits remain to be established. Previous studies have implicated the medial frontal cortex in conflict monitoring and the control of voluntary action, suggesting that these key processes are functionally related or share neural substrates. Here, we combine a novel behavioral paradigm with functional imaging of the oculomotor system to reveal, for the first time, a functional subdivision of the pre-supplementary motor area (pre-SMA) into anatomically distinct areas that respond exclusively to either volition or conflict. We also demonstrate that activity in the supplementary eye field (SEF) distinguishes between success and failure in changing voluntary action plans during conflict, suggesting a role for the SEF in implementing the resolution of conflicting actions. We propose a functional architecture of human medial frontal cortex that incorporates the generation of action plans and the resolution of conflict.

Bilateral medial medullary infarction due to bilateral vertebral artery dissection.

PubMed

Fukuda, Masafumi; Aiba, Toyotaka; Takahashi, Sho

2004-03-01

We describe a 52-year-old woman who experienced transient motor weakness and numbness of the left extremities and presented 2 days later with severe hemiparesis and sensory impairment of the right extremities and right lingual palsy. Magnetic resonance imaging (MRI) revealed bilateral upper medial medullary infarction, primarily in the left ventral portion. The findings of both three-dimensional (3D) computed tomographic and conventional angiography suggested dissection of both intracranial vertebral arteries (VAs). Medial medullary infarction is generally caused by atherosclerosis within a VA or anterior spinal artery. This is the first report of bilateral medial medullary infarction due to dissection of both intracranial VAs.

Benefit of cup medialization in total hip arthroplasty is associated with femoral anatomy.

PubMed

Terrier, Alexandre; Levrero Florencio, Francesc; Rüdiger, Hannes A

2014-10-01

Medialization of the cup with a respective increase in femoral offset has been proposed in THA to increase abductor moment arms. Insofar as there are potential disadvantages to cup medialization, it is important to ascertain whether the purported biomechanical benefits of cup medialization are large enough to warrant the downsides; to date, studies regarding this question have disagreed. The purpose of this study was to quantify the effect of cup medialization with a compensatory increase in femoral offset compared with anatomic reconstruction for patients undergoing THA. We tested the hypothesis that there is a (linear) correlation between preoperative anatomic parameters and muscle moment arm increase caused by cup medialization. Fifteen patients undergoing THA were selected, covering a typical range of preoperative femoral offsets. For each patient, a finite element model was built based on a preoperative CT scan. The model included the pelvis, femur, gluteus minimus, medius, and maximus. Two reconstructions were compared: (1) anatomic position of the acetabular center of rotation, and (2) cup medialization compensated by an increase in the femoral offset. Passive abduction-adduction and flexion-extension were simulated in the range of normal gait. Muscle moment arms were evaluated and correlated to preoperative femoral offset, acetabular offset, height of the greater trochanter (relative to femoral center of rotation), and femoral antetorsion angle. The increase of muscle moment arms caused by cup medialization varied among patients. Muscle moment arms increase by 10% to 85% of the amount of cup medialization for abduction-adduction and from -35% (decrease) to 50% for flexion-extension. The change in moment arm was inversely correlated (R(2) = 0.588, p = 0.001) to femoral antetorsion (anteversion), such that patients with less femoral antetorsion gained more in terms of hip muscle moments. No linear correlation was observed between changes in moment arm and

Dynamic Changes in Acetylcholine Output in the Medial Striatum during Place Reversal Learning

ERIC Educational Resources Information Center

Ragozzino, Michael E.; Choi, Daniel

2004-01-01

The present studies explored the role of the medial striatum in learning when task contingencies change. Experiment 1 examined whether the medial striatum is involved in place reversal learning. Testing occurred in a modified cross-maze across two consecutive sessions. Injections of the local anesthetic, bupivacaine, into the medial striatum, did…

Increased GABA Levels in Medial Prefrontal Cortex of Young Adults with Narcolepsy

PubMed Central

Kim, Seog Ju; Lyoo, In Kyoon; Lee, Yujin S.; Sung, Young Hoon; Kim, Hengjun J.; Kim, Jihyun H.; Kim, Kye Hyun; Jeong, Do-Un

2008-01-01

Study Objectives: To explore absolute concentrations of brain metabolites including gamma amino-butyric acid (GABA) in the medial prefrontal cortex and basal ganglia of young adults with narcolepsy. Design: Proton magnetic resonance (MR) spectroscopy centered on the medial prefrontal cortex and the basal ganglia was acquired. The absolute concentrations of brain metabolites including GABA and glutamate were assessed and compared between narcoleptic patients and healthy comparison subjects. Setting: Sleep and Chronobiology Center at Seoul National University Hospital; A high strength 3.0 Tesla MR scanner in the Department of Radiology at Seoul National University Hospital. Patients or Participants: Seventeen young adults with a sole diagnosis of HLA DQB1 0602 positive narcolepsy with cataplexy (25.1 ± 4.6 years old) and 17 healthy comparison subjects (26.8 ± 4.8 years old). Interventions: N/A. Measurements and Results: Relative to comparison subjects, narcoleptic patients had higher GABA concentration in the medial prefrontal cortex (t = 4.10, P <0.001). Narcoleptic patients with nocturnal sleep disturbance had higher GABA concentration in the medial prefrontal cortex than those without nocturnal sleep disturbance (t = 2.45, P= 0.03), but had lower GABA concentration than comparison subjects (t = 2.30, P = 0.03). Conclusions: The current study reports that young adults with narcolepsy had a higher GABA concentration in the medial prefrontal cortex, which was more prominent in patients without nocturnal sleep disturbance. Our findings suggest that the medial prefrontal GABA level may be increased in narcolepsy, and the increased medial prefrontal GABA might be a compensatory mechanism to reduce nocturnal sleep disturbances in narcolepsy. Citation: Kim SJ; Lyoo IK; Lee YS; Sung YH; Kim HJ; Kim JH; Kim KH; Jeong DU. Increased GABA levels in medial prefrontal cortex of young adults with narcolepsy. SLEEP 2008;31(3):342-347. PMID:18363310

[SECOT consensus on medial femorotibial osteoarthritis].

PubMed

Moreno, A; Silvestre, A; Carpintero, P

2013-01-01

A consensus, prepared by SECOT, is presented on the management of medial knee compartment osteoarthritis, in order to establish clinical criteria and recommendations directed at unifying the criteria in its management, dealing with the factors involved in the pathogenesis of medial femorotibial knee osteoarthritis, the usefulness of diagnostic imaging techniques, and the usefulness of arthroscopy. Conservative and surgical treatments are also analysed. The experts consulted showed a consensus (agreed or disagreed) in 65.8% of the items considered, leaving 14items where no consensus was found, which included the aetiopathogenesis of the osteoarthritis, the value of NMR in degenerative disease, the usefulness of COX-2 and the chondroprotective drugs, as well as on the ideal valgus tibial osteotomy technique. © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

Disruption of the Aortic Elastic Lamina and Medial Calcification Share Genetic Determinants in Mice

PubMed Central

Wang, Susanna S.; Martin, Lisa J.; Schadt, Eric E.; Meng, Haijin; Wang, Xuping; Zhao, Wei; Ingram-Drake, Leslie; Nebohacova, Martina; Mehrabian, Margarete; Drake, Thomas A.; Lusis, Aldons J.

2010-01-01

Background Disruption of the elastic lamina, as an early indicator of aneurysm formation, and vascular calcification frequently occur together in atherosclerotic lesions of humans. Methods and Results We now report evidence of shared genetic basis for disruption of the elastic lamina (medial disruption) and medial calcification in an F2 mouse intercross between C57BL/6J and C3H/HeJ on a hyperlipidemic apolipoprotein E (ApoE−/−) null background. We identified 3 quantitative trait loci (QTLs) on chromosomes 6, 13, and 18, which are common to both traits, and 2 additional QTLs for medial calcification on chromosomes 3 and 7. Medial disruption, including severe disruptions leading to aneurysm formation, and medial calcification were highly correlated and occurred concomitantly in the cross. The chromosome 18 locus showed a striking male sex-specificity for both traits. To identify candidate genes, we integrated data from microarray analysis, genetic segregation, and clinical traits. The chromosome 7 locus contains the Abcc6 gene, known to mediate myocardial calcification. Using transgenic complementation, we show that Abcc6 also contributes to aortic medial calcification. Conclusions Our data indicate that calcification, though possibly contributory, does not always lead to medial disruption and that in addition to aneurysm formation, medial disruption may be the precursor to calcification. PMID:20031637

The Role of Medial Frontal Cortex in Action Anticipation in Professional Badminton Players.

PubMed

Xu, Huan; Wang, Pin; Ye, Zhuo'er; Di, Xin; Xu, Guiping; Mo, Lei; Lin, Huiyan; Rao, Hengyi; Jin, Hua

2016-01-01

Some studies show that the medial frontal cortex is associated with more skilled action anticipation, while similar findings are not observed in some other studies, possibly due to the stimuli employed and the participants used as the control group. In addition, no studies have investigated whether there is any functional connectivity between the medial frontal cortex and other brain regions in more skilled action anticipation. Therefore, the present study aimed to re-investigate how the medial frontal cortex is involved in more skilled action anticipation by circumventing the limitations of previous research and to investigate that the medial frontal cortex functionally connected with other brain regions involved in action processing in more skilled action anticipation. To this end, professional badminton players and novices were asked to anticipate the landing position of the shuttlecock while watching badminton match videos or to judge the gender of the players in the matches. The video clips ended right at the point that the shuttlecock and the racket came into contact to reduce the effect of information about the trajectory of the shuttlecock. Novices who lacked training and watching experience were recruited for the control group to reduce the effect of sport-related experience on the medial frontal cortex. Blood oxygenation level-dependent activation was assessed by means of functional magnetic resonance imaging. Compared to novices, badminton players exhibited stronger activation in the left medial frontal cortex during action anticipation and greater functional connectivity between left medial frontal cortex and some other brain regions (e.g., right posterior cingulate cortex). Therefore, the present study supports the position that the medial frontal cortex plays a role in more skilled action anticipation and that there is a specific brain network for more skilled action anticipation that involves right posterior cingulate cortex, right fusiform gyrus

Ecological divergence and medial cuneiform morphology in gorillas.

PubMed

Tocheri, Matthew W; Solhan, Christyna R; Orr, Caley M; Femiani, John; Frohlich, Bruno; Groves, Colin P; Harcourt-Smith, William E; Richmond, Brian G; Shoelson, Brett; Jungers, William L

2011-02-01

Gorillas are more closely related to each other than to any other extant primate and are all terrestrial knuckle-walkers, but taxa differ along a gradient of dietary strategies and the frequency of arboreality in their behavioral repertoire. In this study, we test the hypothesis that medial cuneiform morphology falls on a morphocline in gorillas that tracks function related to hallucial abduction ability and relative frequency of arboreality. This morphocline predicts that western gorillas, being the most arboreal, should display a medial cuneiform anatomy that reflects the greatest hallucial abduction ability, followed by grauer gorillas, and then by mountain gorillas. Using a three-dimensional methodology to measure angles between articular surfaces, relative articular and nonarticular areas, and the curvatures of the hallucial articular surface, the functional predictions are partially confirmed in separating western gorillas from both eastern gorillas. Western gorillas are characterized by a more medially oriented, proportionately larger, and more mediolaterally curved hallucial facet than are eastern gorillas. These characteristics follow the predictions for a more prehensile hallux in western gorillas relative to a more stable, plantigrade hallux in eastern gorillas. The characteristics that distinguish eastern gorilla taxa from one another appear unrelated to hallucial abduction ability or frequency of arboreality. In total, this reexamination of medial cuneiform morphology suggests differentiation between eastern and western gorillas due to a longstanding ecological divergence and more recent and possibly non-adaptive differences between eastern taxa. Published by Elsevier Ltd.

To pair or not to pair: chromosome pairing and evolution.

PubMed

Moore, G

1998-04-01

Chromosome pairing in wild-type wheat closely resembles the process in both yeast and Drosophila. The recent characterisation of a mutant Ph1 wheat and the observation that chromosome pairing in the absence of Ph1 more closely resembles that of mammals and maize has shed light on the evolution of chromosome pairing in the cereals.

Bilateral medial medullary syndrome secondary to Takayasu arteritis.

PubMed

Deshpande, Anirudda; Chandran, Vijay; Pai, Aparna; Rao, Suryanarayana; Shetty, Ranjan

2013-08-13

Medial medullary syndrome (MMS) is a rare type of stroke which results due to occlusion of the anterior spinal artery or vertebral artery or its branches. In this case report we present a patient who developed MMS secondary to Takayasu arteritis (TA). TA is a chronic inflammatory arteritis primarily involving the arch of aorta and its branches, which in our patient resulted in occlusion of subclavian arteries as well as infarction of the medial medulla bilaterally. To our knowledge this is the first time that MMS has been found to occur secondary to TA.

Phonatory Effects of Type I Thyroplasty Implant Shape and Depth of Medialization in Unilateral Vocal Fold Paralysis

PubMed Central

Orestes, Michael I.; Neubauer, Juergen; Sofer, Elazar; Salinas, Jonathon; Chhetri, Dinesh K.

2015-01-01

Objectives/Hypothesis Medialization thyroplasty (MT) is commonly used to treat glottic insufficiency. In this study, we investigated the phonatory effects of MT implant medialization depth and medial surface shape. Methods Recurrent laryngeal nerve (RLN) and vagal paralysis were simulated in an in vivo canine. A type 1 MT was performed using a silicone elastomer implant with variable medialization depths and medial surface shapes: rectangular, V-shaped, divergent, and convergent. The effects on phonation onset flow/pressure relationships and acoustics were measured. Results Increasing depth of medialization led to improvements in fundamental frequency (F0) range and normalization of the slope of pressure/flow relationship toward baseline activation conditions. The effects of implant medial shape also depended on depth of medialization. Outcome measures were similar among the implants at smaller medialization depths. With large medialization depths and vagal paralysis conditions, the divergent implant maintained pressure/flow relationship closer to baseline. The vagal paralysis conditions also demonstrated decreased fundamental frequency range and worse flow/pressure relationship compared to RLN paralysis. Conclusions The depth and medial shape of a medialization laryngoplasty (ML) implant significantly affect both the F0 range and aerodynamic power required for phonation. These effects become more notable with increasing depth of medialization. The study also illustrates that ML is less effective in vagal paralysis compared to RLN paralysis. PMID:25046146

Lateral Meniscal Allograft Transplant via a Medial Approach Leads to Less Extrusion.

PubMed

Choi, Nam-Hong; Choi, Jeong-Ki; Yang, Bong-Seok; Lee, Doe-Hyun; Victoroff, Brian N

2017-10-01

Accurate positioning of the bony bridge is crucial to prevent extrusion of meniscal allografts after transplant. However, oblique or lateralized placement of the bony bridge of the lateral meniscal allograft may occur due to technical error or a limited visual field. The patellar tendon may be an obstacle to approaching the anterior horn of the lateral meniscus, resulting in a laterally placed allograft. Therefore, lateral meniscal transplant through a medial arthrotomy would be an alternative approach. However, no report exists regarding allograft extrusion when comparing medial and lateral arthrotomy techniques in lateral meniscal transplants. Extrusion of the midbody of the allograft is less severe and the rotation of the bony bridge is less oblique in lateral meniscal allograft transplants through the medial parapatellar approach than those through the lateral approach. Cohort study; Level of evidence, 3. A bony bridge was used to perform 55 lateral meniscal transplants through either a medial or a lateral arthrotomy. Thirty-two allografts were transplanted through a medial arthrotomy and 23 were transplanted through a lateral arthrotomy, not randomly. Because correct positioning of the bony trough through the medial arthrotomy was easier than that through the lateral arthrotomy, the method of the arthrotomy was changed for the latter. The procedure for both groups was identical except for the arthrotomy technique, and rehabilitation was identical for both groups. Follow-up magnetic resonance imaging was conducted for all patients to measure the postoperative extrusion and obliquity of the bony bridge of the allograft. On the coronal view, extrusion was measured as the distance between the outer edge of the articular cartilage of the lateral tibial plateau and the outer edge of the meniscal allograft. On the axial view, a line (line B) was drawn along the longitudinal axis of the bony bridge. The posterior tibial condylar tangential line was drawn between the

Does Medial Meniscal Allograft Transplantation With the Bone-Plug Technique Restore the Anatomic Location of the Native Medial Meniscus?

PubMed

Kim, Nam-Ki; Bin, Seong-Il; Kim, Jong-Min; Lee, Chang-Rack

2015-12-01

Previous work has shown the importance of restoring the normal structure of the native meniscus with meniscal allograft transplantation. The purpose of this study was to compare the anatomic positions of the anterior horn and posterior horn between the preoperative medial meniscus and the postoperative meniscal allograft after medial meniscal allograft transplantation with the bone-plug technique. The hypothesis was that the bone-plug technique could restore the preoperative structure of the native medial meniscus. Case series; Level of evidence, 4. Between December 1999 and December 2013, a total of 59 patients (49 male, 10 female) underwent medial meniscal allograft transplantation by use of the bone-plug technique. The anatomic positions of both horns in the native medial meniscus and in the meniscal allograft were measured via MRI. The percentage reference method was used to measure the locations of both horns. On coronal MRI, the mean absolute distance of the posterior horn from the lateral border of the tibial plateau changed from 45.2 ± 3.3 to 48.1 ± 4.2 mm (P < .05), and the percentage distance of the posterior horn changed from 59.6% to 63.0% (P < .05). On sagittal MRI, the mean absolute distance of the posterior horn from the anterior reference point changed from 40.3 ± 3.0 to 42.0 ± 3.5 mm (P < .05), and the mean percentage distance of the posterior horn changed from 76.5% to 79.4% (P <.05). On coronal MRI, the mean absolute distance of the anterior horn from the lateral border of the tibial plateau changed from 41.3 ± 4.2 to 48.5 ± 5.6 mm (P < .05), and the mean percentage distance of the anterior horn changed from 54.5% to 63.8% (P < .05). On sagittal MRI, the mean absolute distance of the anterior horn from the anterior reference point changed from 5.5 ± 1.0 to 9.9 ± 2.9 mm (P < .05), and the mean percentage distance of the anterior horn changed from 10.6% to 19.0% (P < .05). Despite attempts to place the meniscal allograft in the same

Lateral trunk lean and medializing the knee as gait strategies for knee osteoarthritis.

PubMed

Gerbrands, T A; Pisters, M F; Theeven, P J R; Verschueren, S; Vanwanseele, B

2017-01-01

To determine (1) if Medial Thrust or Trunk Lean reduces the knee adduction moment (EKAM) the most during gait in patients with medial knee osteoarthritis, (2) if the best overall strategy is the most effective for each patient and (3) if these strategies affect ankle and hip kinetics. Thirty patients with symptomatic medial knee osteoarthritis underwent 3-dimensional gait analysis. Participants received verbal instructions on two gait strategies (Trunk Lean and Medial Thrust) in randomized order after comfortable walking was recorded. The peaks and impulse of the EKAM and strategy-specific kinematic and kinetic variables were calculated for all conditions. Early stance EKAM peak was significantly reduced during Medial Thrust (-29%). During Trunk Lean, early and late stance EKAM peak and EKAM impulse reduced significantly (38%, 21% and -25%, respectively). In 79% of the subjects, the Trunk Lean condition was significantly more effective in reducing EKAM peak than Medial Thrust. Peak ankle dorsi and plantar flexion, knee flexion and hip extension and adduction moments were not significantly increased. Medial Thrust and Trunk Lean reduced the EKAM during gait in patients with knee osteoarthritis. Individual selection of the most effective gait modification strategy seems vital to optimally reduce dynamic knee loading during gait. No detrimental effects on external ankle and hip moments or knee flexion moments were found for these conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Bilateral Vocal Fold Medialization: A Treatment for Abductor Spasmodic Dysphonia.

PubMed

Dewan, Karuna; Berke, Gerald S

2017-11-10

Abductor spasmodic dysphonia, a difficult-to-treat laryngologic condition, is characterized by spasms causing the vocal folds to remain abducted despite efforts to adduct them during phonation. Traditional treatment for abductor spasmodic dysphonia-botulinum toxin injection into the posterior cricoarytenoid muscle-can be both technically challenging and uncomfortable. Due to the difficulty of needle placement, it is often unsuccessful. The purpose of this investigation is to present a previously undescribed treatment for abductor spasmodic dysphonia-bilateral vocal fold medialization. A retrospective case review of all cases of abductor spasmodic dysphonia treated in a tertiary care laryngology practice with bilateral vocal fold medialization over a 10-year period was performed. The Voice Handicap Index and the Voice-Related Quality of Life surveys were utilized to assess patient satisfaction with voice outcome. Six patients with abductor spasmodic dysphonia treated with bilateral vocal fold medialization were identified. Disease severity ranged from mild to severe. All six patients reported statistically significant improvement in nearly all Voice Handicap Index and Voice-Related Quality of Life parameters. They reported fewer voice breaks and greater ease of communication. Results were noted immediately and symptoms continue to be well controlled for many years following medialization. Bilateral vocal fold medialization is a safe and effective treatment for abductor spasmodic dysphonia. It is performed under local anesthesia and provides phonation improvement in the short and long term. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Medial joint space widening of the ankle in displaced Tillaux and Triplane fractures in children.

PubMed

Gourineni, Prasad; Gupta, Asheesh

2011-10-01

Tillaux and Triplane fractures occur in children predominantly from external rotation mechanism. We hypothesized that in displaced fractures, the talus would shift laterally along with the distal fibula and the distal tibial epiphyseal fragment increasing the medial joint space. Consecutive cases evaluated retrospectively. Level I and Level II centers. Twenty-two skeletally immature patients with 14 displaced Triplane fractures and eight displaced Tillaux fractures were evaluated for medial joint space widening. Measurement of fracture displacement and medial joint space widening before and after intervention. Thirteen Triplane and six Tillaux fractures (86%) showed medial space widening of 1 to 9 mm and equal to the amount of fracture displacement. Reduction of the fracture reduced the medial space to normal. There were no known complications. Medial space widening of the ankle may be a sign of ankle fracture displacement. Anatomic reduction of the fracture reduces the medial space and may improve the results in Tillaux and Triplane fractures.

Volition and conflict in human medial frontal cortex

PubMed Central

Nachev, Parashkev; Rees, Geraint; Parton, Andrew; Kennard, Christopher; Husain, Masud

2009-01-01

Summary Controversy surrounds the role of human medial frontal cortex in controlling actions[1-5]. Although damage to this area leads to severe difficulties in spontaneously initiating actions[6], the precise mechanisms underlying such ‘volitional’ deficits remain to be established. Previous studies have implicated the medial frontal cortex in conflict monitoring[7-10] and the control of voluntary action[11, 12], suggesting that these key processes are functionally related or share neural substrates. Here we combine a novel behavioural paradigm with functional imaging of the oculomotor system to reveal for the first time a functional subdivision of the pre-supplementary motor area (pre-SMA) into anatomically distinct areas responding exclusively to volition or to conflict. We also demonstrate that activity in the supplementary eye field (SEF) distinguishes between success and failure in changing voluntary action plans during conflict, suggesting a role for the SEF in implementing the resolution of conflicting actions. We propose a functional architecture of human medial frontal cortex that incorporates the generation of action plans and the resolution of conflict. PMID:15668167

Medial Tibial Stress Shielding: A Limitation of Cobalt Chromium Tibial Baseplates.

PubMed

Martin, J Ryan; Watts, Chad D; Levy, Daniel L; Kim, Raymond H

2017-02-01

Stress shielding is a well-recognized complication associated with total knee arthroplasty. However, this phenomenon has not been thoroughly described. Specifically, no study to our knowledge has evaluated the radiographic impact of utilizing various tibial component compositions on tibial stress shielding. We retrospectively reviewed 3 cohorts of 50 patients that had a preoperative varus deformity and were implanted with a titanium, cobalt chromium (CoCr), or an all polyethylene tibial implant. A radiographic comparative analysis was performed to evaluate the amount of medial tibial bone loss in each cohort. In addition, a clinical outcomes analysis was performed on the 3 cohorts. The CoCr was noted to have a statistically significant increase in medial tibial bone loss compared with the other 2 cohorts. The all polyethylene cohort had a statistically significantly higher final Knee Society Score and was associated with the least amount of stress shielding. The CoCr tray is the most rigid of 3 implants that were compared in this study. Interestingly, this cohort had the highest amount of medial tibial bone loss. In addition, 1 patient in the CoCr cohort had medial soft tissue irritation which was attributed to a prominent medial tibial tray which required revision surgery to mitigate the symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

Medial prefrontal cortex supports source memory accuracy for self-referenced items

PubMed Central

Leshikar, Eric D.; Duarte, Audrey

2013-01-01

Previous behavioral work suggests that processing information in relation to the self enhances subsequent item recognition. Neuroimaging evidence further suggests that regions along the cortical midline, particularly those of the medial prefrontal cortex, underlie this benefit. There has been little work to date, however, on the effects of self-referential encoding on source memory accuracy or whether the medial prefrontal cortex might contribute to source memory for self-referenced materials. In the current study, we used fMRI to measure neural activity while participants studied and subsequently retrieved pictures of common objects superimposed on one of two background scenes (sources) under either self-reference or self-external encoding instructions. Both item recognition and source recognition were better for objects encoded self-referentially than self-externally. Neural activity predictive of source accuracy was observed in the medial prefrontal cortex (BA 10) at the time of study for self-referentially but not self-externally encoded objects. The results of this experiment suggest that processing information in relation to the self leads to a mnemonic benefit for source level features, and that activity in the medial prefrontal cortex contributes to this source memory benefit. This evidence expands the purported role that the medial prefrontal cortex plays in self-referencing. PMID:21936739

Medial prefrontal cortex supports source memory accuracy for self-referenced items.

PubMed

Leshikar, Eric D; Duarte, Audrey

2012-01-01

Previous behavioral work suggests that processing information in relation to the self enhances subsequent item recognition. Neuroimaging evidence further suggests that regions along the cortical midline, particularly those of the medial prefrontal cortex (PFC), underlie this benefit. There has been little work to date, however, on the effects of self-referential encoding on source memory accuracy or whether the medial PFC might contribute to source memory for self-referenced materials. In the current study, we used fMRI to measure neural activity while participants studied and subsequently retrieved pictures of common objects superimposed on one of two background scenes (sources) under either self-reference or self-external encoding instructions. Both item recognition and source recognition were better for objects encoded self-referentially than self-externally. Neural activity predictive of source accuracy was observed in the medial PFC (Brodmann area 10) at the time of study for self-referentially but not self-externally encoded objects. The results of this experiment suggest that processing information in relation to the self leads to a mnemonic benefit for source level features, and that activity in the medial PFC contributes to this source memory benefit. This evidence expands the purported role that the medial PFC plays in self-referencing.

Aging, self-referencing, and medial prefrontal cortex.

PubMed

Gutchess, Angela H; Kensinger, Elizabeth A; Schacter, Daniel L

2007-01-01

The lateral prefrontal cortex undergoes both structural and functional changes with healthy aging. In contrast, there is little structural change in the medial prefrontal cortex, but relatively little is known about the functional changes to this region with age. Using an event-related fMRI design, we investigated the response of medial prefrontal cortex during self-referencing in order to compare age groups on a task that young and elderly perform similarly and that is known to actively engage the region in young adults. Nineteen young (M age = 23) and seventeen elderly (M age = 72) judged whether adjectives described themselves, another person, or were presented in upper case. We assessed the overlap in activations between young and elderly for the self-reference effect (self vs. other person), and found that both groups engage medial prefrontal cortex and mid-cingulate during self-referencing. The only cerebral differences between the groups in self versus other personality assessment were found in somatosensory and motor-related areas. In contrast, age-related modulations were found in the cerebral network recruited for emotional valence processing. Elderly (but not young) showed increased activity in the dorsal prefrontal cortex for positive relative to negative items, which could reflect an increase in controlled processing of positive information for elderly adults.

The potential effect of anatomic relationship between the femur and the tibia on medial meniscus tears.

PubMed

Bozkurt, Murat; Unlu, Serhan; Cay, Nurdan; Apaydin, Nihal; Dogan, Metin

2014-10-01

The anatomic and the kinematical relationships between the femur and the tibia have been previously examined in both normal and diseased knees. However, less attention has been directed to the effect of these relationships on the meniscal diseases. Therefore, we aimed to investigate the impact of femorotibial incongruence on both lateral and medial meniscal tears. A total of 100 images obtained from MRI of 100 patients (39 males and 61 females) were included in the study. Diameters of the medial and the lateral femoral condyles, thicknesses of the menisci, and diameters of the medial and the lateral tibial articular surfaces were measured. The medial meniscus tear was detected in 40 (40 %) patients. However, no lateral meniscus tear was found. Significant relationships were found between the diameters of the posterior medial femoral condyle and the medial tibial superior articular surface and between the diameters of the posterior lateral femoral condyle and the lateral tibial superior articular surface. The mean values for the diameter of the medial condyle of the femur, the lateral condyle of the femur, the medial superior articular surface of the tibia, and the lateral superior articular surface of the tibia were found to be significantly higher in cases with meniscus tear compared to cases without meniscus tear. However, no significant difference was present regarding the thicknesses of the medial and the lateral menisci. A positive relationship between the diameter of the posterior medial femoral condyle and the tibial medial superior articular surface was found in cases with (n = 40) (r (2) = 0.208, p = 0.003) and without tear (n = 60) (r (2) = 0.182, p = 0.001). In addition, a significant positive relationship was found between the diameter of the posterior medial femoral condyle and the medial tibial superior articular surface in cases with and without tear. The impact of femorotibial incongruence on the medial meniscus tear is important for

Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study.

PubMed

Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-Ichi

2017-06-18

To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau.

Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study

PubMed Central

Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-ichi

2017-01-01

AIM To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). METHODS A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. RESULTS Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. CONCLUSION We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau. PMID:28660141

Pullout failure strength of the posterior horn of the medial meniscus with root ligament tear.

PubMed

Kim, Young-Mo; Joo, Yong-Bum

2013-07-01

To evaluate the reparability of the posterior horn of the medial meniscus with root ligament tear by measuring the actual pullout failure strength of a simple vertical suture of an arthroscopic subtotal meniscectomized posterior horn of the medial meniscus. From November 2009 to May 2010, nine posterior horns of the medial meniscus specimens were collected from arthroscopic subtotal meniscectomy performed as a treatment for root ligament rupture of the posterior horn of the medial meniscus. Simple vertical sutures were performed on the specimens, and pullout failure load was tested with a biaxial servohydraulic testing machine (Model 8874; Instron Corp., Norwood, MA, USA). The degree of degeneration, extrusion, and medial displacement of the medial meniscus were evaluated with magnetic resonance imaging (MRI). The Kellgren-Lawrence classification was used in standing plain radiography, and mechanical alignment was measured using orthoroentgenography. Tear morphology was classified into ligament proper type or meniscoligamentous junctional type according to the site of the torn root ligament of the posterior horn of the medial meniscus during arthroscopy. The mean pullout failure strength of the posterior horn of the medial meniscus was 71.6 ± 23.2 N (range, 41.4-107.7 N). The degree of degeneration of the posterior horn of the medial meniscus on MRI showed statistically significant correlation with pullout failure strength and Kellgren-Lawrence classification. Pullout failure strength showed correlation with mechanical alignment and Kellgren-Lawrence classification (P < 0.05). The measurement of pullout failure strength of the posterior horn of the medial meniscus with root ligament tear showed a degree of repairability. The degree of degeneration of the posterior horn of the medial meniscus on MRI showed a significant correlation with the pullout failure strength. The pullout failure strength was also not only correlated with the degree of degeneration of the

Functional specialization of medial auditory belt cortex in the alert rhesus monkey.

PubMed

Kusmierek, Pawel; Rauschecker, Josef P

2009-09-01

Responses of neural units in two areas of the medial auditory belt (middle medial area [MM] and rostral medial area [RM]) were tested with tones, noise bursts, monkey calls (MC), and environmental sounds (ES) in microelectrode recordings from two alert rhesus monkeys. For comparison, recordings were also performed from two core areas (primary auditory area [A1] and rostral area [R]) of the auditory cortex. All four fields showed cochleotopic organization, with best (center) frequency [BF(c)] gradients running in opposite directions in A1 and MM than in R and RM. The medial belt was characterized by a stronger preference for band-pass noise than for pure tones found medially to the core areas. Response latencies were shorter for the two more posterior (middle) areas MM and A1 than for the two rostral areas R and RM, reaching values as low as 6 ms for high BF(c) in MM and A1, and strongly depended on BF(c). The medial belt areas exhibited a higher selectivity to all stimuli, in particular to noise bursts, than the core areas. An increased selectivity to tones and noise bursts was also found in the anterior fields; the opposite was true for highly temporally modulated ES. Analysis of the structure of neural responses revealed that neurons were driven by low-level acoustic features in all fields. Thus medial belt areas RM and MM have to be considered early stages of auditory cortical processing. The anteroposterior difference in temporal processing indices suggests that R and RM may belong to a different hierarchical level or a different computational network than A1 and MM.

[Tibial periostitis ("medial tibial stress syndrome")].

PubMed

Fournier, Pierre-Etienne

2003-06-01

Medial tibial stress syndrome is characterised by complaints along the posteromedial tibia. Runners and athletes involved in jumping activities may develop this syndrome. Increased stress to stabilize the foot especially when excessive pronation is present explain the occurrence this lesion.

Vibrational mode and sound radiation of electrostatic speakers using circular and annular diaphragms

NASA Astrophysics Data System (ADS)

Huang, Yu-Hsi; Chiang, Hsin-Yuan

2016-06-01

This study modeled two diaphragms comprising a pair of indium tin oxide (ITO) transparent plates sandwiching a vibrating diaphragm to create circular (30 mm radius) and annular (30 mm outer and 3 mm inner radius) push-pull electrostatic speakers. We then measured the displacement amplitudes and mode shapes produced by the devices. Vibration characteristics were used to predict sound pressure levels (SPLs) using the lumped parameter method (LPM) and distributed parameter method (DPM). The two measurement results obtained using a laser system were compared to the SPLs obtained using traditional acoustic measurement (AM) from 20 Hz to 20 kHz in order to verify our predictions. When using LPM and DPM, the SPL prediction results in the first three symmetric modes were in good agreement with the AM results. Under the assumption of linear operations, the DPM and amplitude-fluctuation electronic speckle pattern interferometry (ESPI) techniques proved effective in determining the visualization of mode shape (0,1)-(0,3). The use of ITO plates is a practical technique for the prediction of SPL, as well as measurement of mode shapes. The four evaluation methods, i.e. LPM, DPM, ESPI and AM, present a high degree of consistency with regard to vibrational mode and sound radiation characteristics.

Does medial tenderness predict deep deltoid ligament incompetence in supination-external rotation type ankle fractures?

PubMed

DeAngelis, Nicola A; Eskander, Mark S; French, Bruce G

2007-04-01

To identify whether medial tenderness is a predictor of deep deltoid ligament incompetence in supination-external rotation ankle fractures. All Weber B lateral malleolar fractures with normal medial clear space over a 9 month period were prospectively included in the study. Fracture patterns not consistent with a supination-external rotation mechanism were excluded. High-volume tertiary care referral center and Level I trauma center. Fifty-five skeletally mature patients with a Weber B lateral malleolar fracture and normal medial clear space presenting to our institution were included. All study patients had ankle anteroposterior, lateral, and mortise radiographs. Each patient was seen and evaluated by an orthopedic specialist and the mechanism of injury was recorded. Each patient was assessed for tenderness to palpation in the region of the deltoid ligament and then had an external rotation stress mortise radiograph. Correlating medial tenderness with deep deltoid competence as measured by stress radiographs. Thirteen patients (23.6%) were tender medially and had a positive external rotation stress radiograph. Thirteen patients (23.6%) were tender medially and had a negative external rotation stress radiograph. Nineteen patients (34.5%) were nontender medially and had a negative external rotation stress radiograph. Ten patients (18.2%) were nontender medially and had a positive external rotation stress radiograph. We calculated a chi statistic of 2.37 as well as the associated P value of 0.12. Medial tenderness as a measure of deep deltoid ligament incompetence had a sensitivity of 57%, a specificity of 59%, a positive predictive value of 50%, a negative predictive value of 66%, and an accuracy of 42%. There was no statistical significance between the presence of medial tenderness and deep deltoid ligament incompetence. There is a 25% chance of the fracture in question with medial tenderness having a positive external rotation stress and a 25% chance the fracture

Medial Frontal Event-Related Potentials and Reward Prediction: Do Responses Matter?

ERIC Educational Resources Information Center

Martin, Laura E.; Potts, Geoffrey F.

2011-01-01

Medial frontal event-related potentials (ERPs) following rewarding feedback index outcome evaluation. The majority of studies examining the feedback related medial frontal negativity (MFN) employ active tasks during which participants' responses impact their feedback, however, the MFN has been elicited during passive tasks. Many of the studies…

Complications in posteromedial arthroscopic suture of the medial meniscus.

PubMed

Jan, N; Sonnery-Cottet, B; Fayard, J-M; Kajetanek, C; Thaunat, M

2016-12-01

All-inside posteromedial suture for lesions of the posterior horn of the medial meniscus in anterior cruciate ligament (ACL) repair provides effective freshening and good healing. The posteromedial portal provides satisfactory healing rates without increasing morbidity or complications rates. Intra- and postoperative complications were collected for a consecutive single-center series of 132 patients undergoing posteromedial hook suture of the medial meniscus in ACL repair. Meniscal healing was assessed as the rate of recurrence of symptomatic medial meniscus lesions (Barret criteria) and on revision surgery, if any, in terms of the aspect and extent of the iterative lesion. The severity of any sensory disorder was assessed by questionnaire. The intraoperative complications rate was 1.5% (2 saphenous vein punctures). At a mean 31months (range, 28-35months), there was no loss to follow-up. Twelve patients (9%) showed symptomatic recurrence of the medial meniscus lesion, requiring 10 repeat surgeries. In 6 cases (4.5%), the iterative lesion involved a smaller, more central part of the meniscus anterior to the sutures, of "postage-stamp" effect, possibly implicating the suture hook and/or non-absorbable sutures. There were no cases of infection or fistula. Postoperative hematoma occurred in 7% of patients. In total, 1.8% reported dysesthesia areas equal to or greater than the size of a credit card (45cm 2 ). Some retears, or "partial failures", may implicate a new lesion caused by the suture hook and possibly prolonged by non-resorbable sutures. Hematoma and sensory disorder rates were comparable to those reported in isolated ACL repair without posteromedial portal. The present results show that posteromedial arthroscopic hook suture in posterior medial meniscus tear provides good healing rates without increased morbidity due to the supplementary portal. IV. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cam impingement of the posterior femoral condyle in medial meniscal tears.

PubMed

Suganuma, Jun; Mochizuki, Ryuta; Yamaguchi, Kenji; Inoue, Yutaka; Yamabe, Eikou; Ueda, Yoshiyuki; Fujinaka, Tarou

2010-02-01

The aim of this study was to compare the results of meniscal repair of the medial meniscus with or without decompression of the posterior segment of the medial meniscus for the treatment of posteromedial tibiofemoral incongruence at full flexion (PMTFI), which induces deformation of the posterior segment on sagittal magnetic resonance imaging (MRI). For more than 2 years, we followed up 27 patients with PMTFI who were classified into the following 2 groups. Group 1 included 8 patients (5 male joints and 3 female joints) with a medial meniscal tear with instability at the site of the tear who underwent meniscal repair. The mean age was 23.6 years. Group 2 included 19 patients (16 male joints and 3 female joints) who had a meniscal tear with instability at the site of the tear and underwent meniscal repair and decompression. The mean age was 26.5 years. In decompression of the posterior segment, redundant bone tissue on the most proximal part of the medial femoral condyle was excised. The patients were assessed by use of the Lysholm score, sagittal MRI at full flexion, and arthroscopic examination. There were no statistical differences in mean Lysholm score between the 2 groups before surgery, but the mean score in group 2 was significantly higher than that in group 1 after surgery. Meniscal deformation of the posterior segment at full flexion on MRI disappeared in all cases after decompression. On second-look arthroscopy, the rate of complete healing at the site of the tear was 0% in group 1 but 57% in group 2, and it was significantly different between these groups. The addition of decompression of the posterior segment of the medial meniscus to meniscal repair of knee joints with PMTFI allowed more room for the medial meniscus to accommodate and improved both function of the knee joint and the rate of success of repair of isolated medial meniscal tears in patients who regularly performed full knee flexion. (c) 2010 Arthroscopy Association of North America

The Role of Medial Frontal Cortex in Action Anticipation in Professional Badminton Players

PubMed Central

Xu, Huan; Wang, Pin; Ye, Zhuo’er; Di, Xin; Xu, Guiping; Mo, Lei; Lin, Huiyan; Rao, Hengyi; Jin, Hua

2016-01-01

Some studies show that the medial frontal cortex is associated with more skilled action anticipation, while similar findings are not observed in some other studies, possibly due to the stimuli employed and the participants used as the control group. In addition, no studies have investigated whether there is any functional connectivity between the medial frontal cortex and other brain regions in more skilled action anticipation. Therefore, the present study aimed to re-investigate how the medial frontal cortex is involved in more skilled action anticipation by circumventing the limitations of previous research and to investigate that the medial frontal cortex functionally connected with other brain regions involved in action processing in more skilled action anticipation. To this end, professional badminton players and novices were asked to anticipate the landing position of the shuttlecock while watching badminton match videos or to judge the gender of the players in the matches. The video clips ended right at the point that the shuttlecock and the racket came into contact to reduce the effect of information about the trajectory of the shuttlecock. Novices who lacked training and watching experience were recruited for the control group to reduce the effect of sport-related experience on the medial frontal cortex. Blood oxygenation level-dependent activation was assessed by means of functional magnetic resonance imaging. Compared to novices, badminton players exhibited stronger activation in the left medial frontal cortex during action anticipation and greater functional connectivity between left medial frontal cortex and some other brain regions (e.g., right posterior cingulate cortex). Therefore, the present study supports the position that the medial frontal cortex plays a role in more skilled action anticipation and that there is a specific brain network for more skilled action anticipation that involves right posterior cingulate cortex, right fusiform gyrus

Transnasal endoscopic medial maxillectomy in recurrent maxillary sinus inverted papilloma.

PubMed

Kamel, Reda H; Abdel Fattah, Ahmed F; Awad, Ayman G

2014-12-01

Maxillary sinus inverted papilloma entails medial maxillectomy and is associated with high incidence of recurrence. To study the impact of prior surgery on recurrence rate after transnasal endoscopic medial maxillectomy. Eighteen patients with primary and 33 with recurrent maxillary sinus inverted papilloma underwent transnasal endoscopic medial maxillectomy. Caldwell-Luc operation was the primary surgery in 12 patients, transnasal endoscopic resection in 20, and midfacial degloving technique in one. The follow-up period ranged between 2 to 19.5 years with an average of 8.8 years. Recurrence was detected in 8/51 maxillary sinus inverted papilloma patients (15.7 %), 1/18 of primary cases (5.5 %), 7/33 of recurrent cases (21.2 %); 3/20 of the transnasal endoscopic resection group (15%) and 4/12 of the Caldwell-Luc group (33.3%). Redo transnasal endoscopic medial maxillectomy was followed by a single recurrence in the Caldwell-Luc group (25%), and no recurrence in the other groups. Recurrence is more common in recurrent maxillary sinus inverted papilloma than primary lesions. Recurrent maxillary sinus inverted papilloma after Caldwell-Luc operation has higher incidence of recurrence than after transnasal endoscopic resection.

Characteristics and prognosis of medial epicondylar fragmentation of the humerus in male junior tennis players.

PubMed

Harada, Mikio; Takahara, Masatoshi; Maruyama, Masahiro; Takagi, Michiaki

2014-10-01

Although medial epicondylar fragmentation of the humerus is a reported elbow injury in junior tennis players, there have been only a few studies on this entity, and none have investigated the characteristics and prognosis of medial epicondylar fragmentation. Forty-one male junior tennis players, aged 11 to 14 years (mean, 13 years), underwent elbow examination by ultrasonography. Elbow re-examination was performed in subjects with medial epicondylar fragmentation at an average of 20 months (12-30 months) after the initial examination. On examination, 9 subjects (22%) had elbow pain. Ultrasonography showed that 6 subjects (15%) had medial epicondylar fragmentation, all of whom had elbow pain. Medial epicondylar fragmentation was present in 5 (38%) of 13 subjects aged 11 to 12 years and in 1 (4%) of 28 aged 13 to 14 years. More subjects aged 11 to 12 years had medial epicondylar fragmentation (P = .0084). All 6 subjects with medial epicondylar fragmentation continued to play tennis between the initial elbow examination and the re-examination. At re-examination, although ultrasonography showed that 5 developed bone union and 1 had nonunion, 3 subjects (50%) reported elbow pain. Our results demonstrated that subjects aged 11 to 12 years had a high frequency (38%) of medial epicondylar fragmentation. Although medial epicondylar fragmentation was the main cause of elbow pain (67%) at the initial elbow examination, all 6 players with medial epicondylar fragmentation continued to play tennis between the initial elbow examination and the re-examination. At re-examination, 5 subjects presented spontaneous bone union (83%), but 3 subjects (50%) reported elbow pain. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Effects of the medial or basolateral amygdala upon social anxiety and social recognition in mice.

PubMed

Wang, Yu; Zhao, Shanshan; Liu, Xu; Fu, Qunying

2014-01-01

Though social anxiety and social recognition have been studied extensively, the roles of the medial or basolateral amygdala in the control of social anxiety and social recognition remain to be determined. This study investigated the effects of excitotoxic bilateral medial or basolateral amygdala lesions upon social anxiety and social recognition in-mice. Animals at 9 weeks of age were given bilateral medial or basolateral amygdala lesions via infusion of N-methyl- D-aspartate and then were used for behavioral tests: anxiety-related tests (including open-field test, light-dark test, and elevated-plus maze test), social behavior test in a novel environment, social recognition test, and flavor recognition test. Medial or basolateral amygdala-lesioned mice showed lower levels of anxiety and increased social behaviors in a novel environment. Destruction of the medial or basolateral amygdala neurons impaired social recognition but not flavor recognition. The medial or basolateral amygdala is involved in the control of anxiety-related behavior (social anxiety and social behaviors) in mice. Moreover, both the medial and the basolateral amygdala are essential for social recognition but not flavor recognition in mice.

Medial Meniscus Root Tear in the Middle Aged Patient: A Case Based Review

PubMed Central

Carreau, Joseph H.

2017-01-01

Abstract Biomechanical studies have shown that medial meniscal root tears result in meniscal extrusion and increased tibiofemoral joint contact pressures, which can accelerate the progression of arthritis. Repair is generally recommended for acute injuries in the young, active patient population. The far more common presentation however, is a subacute root tear with medial meniscal extrusion in a middle aged patient. Coexisting arthritis is common in this population and complicates decision making. Treatment should be based on the severity of the underlying arthritis. In cases of early or minimal arthritis, root repair is ideal to improve symptoms and restore meniscal function. In patients with moderate or severe medial compartment arthritis, medial unloader bracing or injections can be tried initially. When non-operative treatment fails, high tibial osteotomy or arthroplasty is recommended. Long term clinical studies are needed to determine the natural history of medial meniscal root tears in middle aged patients and the best surgical option. PMID:28852346

Proximo-distal patellar position in three small dog breeds with medial patellar luxation.

PubMed

Wangdee, C; Theyse, L F H; Hazewinkel, H A W

2015-01-01

Medial patellar luxation is thought to be associated with a high proximal position of the patella in the trochlear groove. To determine whether the ratio of patellar ligament length and patellar length (L:P) is influenced by the stifle angle (75°, 96°, 113°, 130°, and 148°) in small dog breeds and to compare the L:P ratio in dogs of three small dog breeds with and without medial patellar luxation. A mediolateral radiograph of the stifle joint was used to measure the L:P ratio in the stifle joints of dogs of three small breeds with and without medial patellar luxation. The L:P ratio was evaluated at five stifle angles (75°, 96°, 113°, 130°, and 148°) in 14 cadavers (26 stifle joints) of small dog breeds in order to identify the best stifle angle to measure the L:P ratio. Then the mean ± SD L:P ratio was calculated for normal stifles and stifles with medial patellar luxation grades 1, 2, and 3 in 194 Pomeranians, 74 Chihuahuas, and 41 Toy or Standard Poodles. The L:P ratio was the same for all five stifle angles in the cadavers (p = 0.195). It was also not significantly different in the three breeds (p = 0.135), in normal and medial patellar luxation-affected stifles overall (p = 0.354), and in normal and medial patellar luxation-affected joints within each breed (p = 0.19). We conclude that a proximo-distal patellar position is not associated with medial patellar luxation in Pomeranians, Chihuahuas, and Toy or Standard Poodles. Thus a longer patellar ligament length does not play a role in the pathophysiology of medial patellar luxation in these small dog breeds.

Epidural abscess treated with a medial supraorbital craniotomy through an incision in the eyebrow. Case report.

PubMed

Rosen, David S; Shafizadeh, Stephen; Baroody, Fuad M; Yamini, Bakhtiar

2008-02-01

The authors describe a medial supraorbital craniotomy performed through a medial eyebrow skin incision to approach an epidural abscess located in the medial anterior fossa of the skull. An 8-year-old boy presented with fevers and facial swelling. Imaging demonstrated pansinusitis and an epidural fluid collection adjacent to the frontal sinus. A medial supraorbital craniotomy was performed to access and drain the epidural abscess. The supraorbital nerve laterally and the supratrochlear nerve medially were preserved by incising the frontalis muscle vertically, parallel to the course of the nerves, and dissecting the subperiosteal plane to mobilize the nerves. This approach may be a useful access corridor for other lesions located near the medial anterior fossa.

Variation Among Pediatric Orthopaedic Surgeons When Treating Medial Epicondyle Fractures.

PubMed

Hughes, Meghan; Dua, Karan; O'Hara, Nathan N; Brighton, Brian K; Ganley, Theodore J; Hennrikus, William L; Herman, Martin J; Hyman, Joshua E; Lawrence, J Todd; Mehlman, Charles T; Noonan, Kenneth J; Otsuka, Norman Y; Schwend, Richard M; Shrader, M Wade; Smith, Brian G; Sponseller, Paul D; Abzug, Joshua M

2017-10-18

Medial epicondyle fractures are a common pediatric and adolescent injury accounting for 11% to 20% of elbow fractures in this population. This purpose of this study was to determine the variability among pediatric orthopaedic surgeons when treating pediatric medial epicondyle fractures. A discrete choice experiment was conducted to determine which patient and injury attributes influence the management of medial epicondyle fractures by pediatric orthopaedic surgeons. A convenience sample of 13 pediatric orthopaedic surgeons reviewed 60 case vignettes of medial epicondyle fractures that included elbow radiographs and patient/injury characteristics. Displacement was incorporated into the study model as a fixed effect. Surgeons were queried if they would treat the injury with immobilization alone or open reduction and internal fixation (ORIF). Statistical analysis was performed using a mixed effect regression model. In addition, surgeons filled out a demographic questionnaire and a risk assessment to determine if these factors affected clinical decision-making. Elbow dislocation and fracture displacement were the only attributes that significantly influenced surgeons to perform surgery (P<0.05). The presence of an elbow dislocation had the largest impact on surgeons when choosing operative care (β=-0.14; P=0.02). In addition, for every 1 mm increase in displacement, surgeons tended to favor ORIF by a factor of 0.09 (P<0.01). Sex, mechanism of injury, and sport participation did not influence decision-making. In total, 54% of the surgeons demonstrated a preference for ORIF for the included scenarios. On the basis of the personality Likert scale, participants were neither high-risk takers nor extremely risk adverse with an average-risk score of 2.24. Participant demographics did not influence decision-making. There is substantial variation among pediatric orthopaedic surgeons when treating medial epicondyle fractures. The decision to operate is significantly based on

Variations in medial-lateral hamstring force and force ratio influence tibiofemoral kinematics.

PubMed

Shalhoub, Sami; Fitzwater, Fallon G; Cyr, Adam J; Maletsky, Lorin P

2016-10-01

A change in hamstring strength and activation is typically seen after injuries or invasive surgeries such as anterior cruciate reconstruction or total knee replacement. While many studies have investigated the influence of isometric increases in hamstring load on knee joint kinematics, few have quantified the change in kinematics due to a variation in medial to lateral hamstring force ratio. This study examined the changes in knee joint kinematics on eight cadaveric knees during an open-chain deep knee bend for six different loading configurations: five loaded hamstring configurations that varied the ratio of a total load of 175 N between the semimembranosus and biceps femoris and one with no loads on the hamstring. The anterior-posterior translation of the medial and lateral femoral condyles' lowest points along proximal-distal axis of the tibia, the axial rotation of the tibia, and the quadriceps load were measured at each flexion angle. Unloading the hamstring shifted the medial and lateral lowest points posteriorly and increased tibial internal rotation. The influence of unloading hamstrings on quadriceps load was small in early flexion and increased with knee flexion. The loading configuration with the highest lateral hamstrings force resulted in the most posterior translation of the medial lowest point, most anterior translation of the lateral lowest point, and the highest tibial external rotation of the five loading configurations. As the medial hamstring force ratio increased, the medial lowest point shifted anteriorly, the lateral lowest point shifted posteriorly, and the tibia rotated more internally. The results of this study, demonstrate that variation in medial-lateral hamstrings force and force ratio influence tibiofemoral transverse kinematics and quadriceps loads required to extend the knee. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1707-1715, 2016. © 2016 Orthopaedic Research Society. Published by

Effects of medial meniscal posterior horn avulsion and repair on meniscal displacement.

PubMed

Hein, Christopher N; Deperio, Jennifer Gurske; Ehrensberger, Mark T; Marzo, John M

2011-06-01

Medial meniscal posterior root avulsion (MMRA) leads to deleterious alteration of medial joint compartment loading profiles and increased risk of medial degenerative changes. Surgical repair restores more normal biomechanics to the knee. Our hypothesis is that MMRA will cause medial meniscal (MM) extrusion and gap formation between the root attachment site and MM. Meniscal root repair will restore the ability of the meniscus to resist extrusion, and reduce gap formation at the defect. Seven fresh frozen human cadaveric knees were dissected and mechanically loaded using a servo-hydraulic load frame (MTS ®) with 0 and 1800 N. The knees were tested under three conditions: native, avulsed, and repaired. Four measurements were obtained: meniscal displacement anteriorly, medially, posteriorly, and gap distance between the root attachment site and MM after transection and repair. The medial displacement of the avulsed MM (3.28 mm) was significantly greater (p < 0.001) than the native knee (1.60mm) and repaired knee (1.46 mm). Gap formation is significantly larger in the avulsed compared to repaired state at 0 (p < 0.02) and 1800N (p < 0.02) and also larger with loading in both avulsed (p < 0.05) and repaired (p < 0.02) conditions. Therefore, MMRA results in MM extrusion from the joint and gap formation between the MM root and the MM. Subsequent surgical repair reduces meniscal displacement and gap formation at the defect. Copyright © 2010 Elsevier B.V. All rights reserved.

Medial maxillectomy in recalcitrant sinusitis: when, why and how?

PubMed

Konstantinidis, Iordanis; Constantinidis, Jannis

2014-02-01

We reviewed all journal articles relevant to endoscopic medial maxillectomy in patients with recalcitrant chronic maxillary sinusitis in order to present all indications, the underlying pathophysiology and the developed surgical techniques. Despite the high success rate of middle meatal antrostomy, cases with persistent maxillary sinus disease exist and often need a more extended endoscopic procedure for the better control of the disease. Such surgical option uses gravity for better sinus drainage and offers better saline irrigation, local application of medications and follow-up inspection. An endoscopic medial maxillectomy and its modified forms offer a wider surgical field and access to all 'difficult' areas of the maxillary sinus. Patients with previous limited endoscopic sinus surgery or extended open surgery, cystic fibrosis, extensive mucoceles, allergic fungal sinusitis, odontogenic infections, foreign bodies and so on may suffer from recurrent disease requiring an endoscopic medial maxillectomy. Depending on the disease, various modifications of the procedure can be performed preserving the anterior buttress, nasolacrimal duct and inferior turbinate if possible.

Avulsion of the anterior medial meniscus root: case report and surgical technique.

PubMed

Feucht, Matthias J; Minzlaff, Philipp; Saier, Tim; Lenich, Andreas; Imhoff, Andreas B; Hinterwimmer, Stefan

2015-01-01

Injuries of the meniscus roots have become increasingly recognised as a serious pathology of the knee joint. However, the current available literature focuses primarily on posterior meniscus root tears. In this article, a case with an isolated avulsion of the anterior medial meniscus root is presented, and a new arthroscopic technique to treat this type of injury is described. The anterior horn of the medial meniscus was sutured with a double-looped nonabsorbable suture and reattached to the tibial plateau using a knotless suture anchor. This technique may also be useful to treat avulsion injuries of the anterolateral or posteromedial meniscus root, and symptomatic subluxation of the medial meniscus in case of a variant insertion anatomy with an absent attachment of the anterior horn of the medial meniscus to the tibial plateau. Level of evidence V.

Medial versus lateral supraspinatus tendon properties: implications for double-row rotator cuff repair.

PubMed

Wang, Vincent M; Wang, Fan Chia; McNickle, Allison G; Friel, Nicole A; Yanke, Adam B; Chubinskaya, Susan; Romeo, Anthony A; Verma, Nikhil N; Cole, Brian J

2010-12-01

Rotator cuff repair retear rates range from 25% to 90%, necessitating methods to improve repair strength. Although numerous laboratory studies have compared single-row with double-row fixation properties, little is known regarding regional (ie, medial vs lateral) suture retention properties in intact and torn tendons. A torn supraspinatus tendon will have reduced suture retention properties on the lateral aspect of the tendon compared with the more medial musculotendinous junction. Controlled laboratory study. Human supraspinatus tendons (torn and intact) were randomly assigned for suture retention mechanical testing, ultrastructural collagen fibril analysis, or histologic testing after suture pullout testing. For biomechanical evaluation, sutures were placed either at the musculotendinous junction (medial) or 10 mm from the free margin (lateral), and tendons were elongated to failure. Collagen fibril assessments were performed using transmission electron microscopy. Intact tendons showed no regional differences with respect to suture retention properties. In contrast, among torn tendons, the medial region exhibited significantly higher stiffness and work values relative to the lateral region. For the lateral region, work to 10-mm displacement (1592 ± 261 N-mm) and maximum load (265 ± 44 N) for intact tendons were significantly higher (P < .05) than that of torn tendons (1086 ± 388 N-mm and 177 ± 71 N, respectively). For medial suture placement, maximum load, stiffness, and work of intact and torn tendons were similar (P > .05). Regression analyses for the intact and torn groups revealed generally low correlations between donor age and the 3 biomechanical indices. For both intact and torn tendons, the mean fibril diameter and area density were greater in the medial region relative to the lateral (P ≤ .05). In the lateral tendon, but not the medial region, torn specimens showed a significantly lower fibril area fraction (48.3% ± 3.8%) than intact specimens

Associated lateral/medial knee instability and its relevant factors in anterior cruciate ligament-injured knees.

PubMed

Yuuki, Arata; Muneta, Takeshi; Ohara, Toshiyuki; Sekiya, Ichiro; Koga, Hideyuki

2017-03-01

Associations of lateral/medial knee instability with anterior cruciate ligament (ACL) injury have not been thoroughly investigated. The purposes of this study were to investigate whether lateral/medial knee instability is associated with ACL injury, and to clarify relevant factors for lateral/medial knee instability in ACL-injured knees. One hundred and nineteen patients with unilateral ACL-injured knees were included. Lateral/medial knee instability was assessed with varus/valgus stress X-ray examination for both injured and uninjured knees by measuring varus/valgus angle, lateral/medial joint opening, and lateral/medial joint opening index. Manual knee instability tests for ACL were evaluated to investigate associations between lateral/medial knee instability and anterior and/or rotational instabilities. Patients' backgrounds were evaluated to identify relevant factors for lateral/medial knee instability. Damage on the lateral collateral ligament (LCL) on MRI was also evaluated. All parameters regarding lateral knee instability in injured knees were significantly greater than in uninjured knees. There were significant correlations between lateral knee instability and the Lachman test as well as the pivot shift test. Patients with LCL damage had significantly greater lateral joint opening than those without LCL damage on MRI. Sensitivity of LCL damage on MRI to lateral joint opening was 100%, while its specificity was 36%. No other relevant factors were identified. In medial knee instability, there were also correlations between medial knee instability and the Lachman test/pivot shift test. However, the correlations were weak and other parameters were not significant. Lateral knee instability was greater in ACL-deficient knees than in uninjured knees. Lateral knee instability was associated with ACL-related instabilities as well as LCL damage on MRI, whereas MRI had low specificity to lateral knee instability. On the other hand, the association of medial knee

Why Do Medial Unicompartmental Knee Arthroplasties Fail Today?

PubMed

van der List, Jelle P; Zuiderbaan, Hendrik A; Pearle, Andrew D

2016-05-01

Failure rates are higher in medial unicompartmental knee arthroplasty (UKA) than total knee arthroplasty. To improve these failure rates, it is important to understand why medial UKA fail. Because individual studies lack power to show failure modes, a systematic review was performed to assess medial UKA failure modes. Furthermore, we compared cohort studies with registry-based studies, early with midterm and late failures and fixed-bearing with mobile-bearing implants. Databases of PubMed, EMBASE, and Cochrane and annual registries were searched for medial UKA failures. Studies were included when they reported >25 failures or when they reported early (<5 years), midterm (5-10 years), or late failures (>10 years). Thirty-seven cohort studies (4 level II studies and 33 level III studies) and 2 registry-based studies were included. A total of 3967 overall failures, 388 time-dependent failures, and 1305 implant design failures were identified. Aseptic loosening (36%) and osteoarthritis (OA) progression (20%) were the most common failure modes. Aseptic loosening (26%) was most common early failure mode, whereas OA progression was more commonly seen in midterm and late failures (38% and 40%, respectively). Polyethylene wear (12%) and instability (12%) were more common in fixed-bearing implants, whereas pain (14%) and bearing dislocation (11%) were more common in mobile-bearing implants. This level III systematic review identified aseptic loosening and OA progression as the major failure modes. Aseptic loosening was the main failure mode in early years and mobile-bearing implants, whereas OA progression caused most failures in late years and fixed-bearing implants. Copyright © 2016 Elsevier Inc. All rights reserved.

Robot-Assisted Medial Compartment Arthroplasty Following Remote Patellectomy: A Case Report

PubMed Central

Kouk, Shalen; Kalbian, Irene; Wolfe, Elizabeth; Strickland, Sabrina M

2018-01-01

Introduction: Total patellectomies are uncommon procedures that are reserved as salvage treatment for severely comminuted fractures of the patella. Due to the alteration of normal joint mechanics, these patients present later on in life with degenerative cartilage damage to the femorotibial joint and altered extensor mechanism. There are very few reports of unicondylar knee arthroplasties following previous patellectomy and none that specifically address robot-assisted unicompartmental knee arthroplasty. A recent case report by Pang et al. described the use of minimally invasive fixed-bearing unicondylar knee arthroplasty in a patellectomized patient with moderate medial compartment osteoarthritis. Our report details a case with more significant chondral loss along with patellar tendon subluxation. Case Report: This is a case report of a patient with severe medial compartment osteoarthritis after a patellectomy following a motor vehicle collision. After failing conservative treatment, the patient underwent a medial MAKOplasty with complete resolution of arthritic pain. Conclusion: Significant pain relief and improved knee function can be achieved with MAKOPlasty partial knee resurfacing system in a previously patellectomized patient with severe medial compartment osteoarthritis. PMID:29854684

Rate of Malunion Following Bi-plane Chevron Medial Malleolar Osteotomy.

PubMed

Bull, Patrick E; Berlet, Gregory C; Canini, Cameron; Hyer, Christopher F

2016-06-01

Access to the medial half of the talus can be challenging even with an osteotomy. Although several techniques are presented in the literature, critical evaluation of fixation, union, and alignment is lacking. The chevron medial malleolar osteotomy provides advantages of perpendicular instrumentation access and wide exposure to the medial talus. Postoperative displacement resulting in malunion, and possibly provoking ankle osteoarthritis, is a known complication. The present study describes our experience with the osteotomy. A consecutive series cohort of 50 bi-plane chevron osteotomies performed from 2004 to 2013 were evaluated. Forty-six were secured using 2 lag screws, and 4 were secured using 2 lag screws and a medial buttress plate. Radiographic studies performed at 2, 6, and 12 weeks and at final follow-up were analyzed for postoperative displacement, malunion, non-union, and hardware-related complications. At initial postoperative follow-up, 47 of 50 had adequate radiographs for review, and 18 of 47 (38.3%) showed some displacement when compared to the initial osteotomy fixation position. By final follow-up, 15 of 50 (30.0%) had measurable incongruence. Hardware removal was performed in 13 (26.0%) cases at an average of 2.4 years postoperation. Bi-plane medial malleolar chevron osteotomy fixed with 2 lag screws showed a 30.0% malunion rate with an average of 2 mm of incongruence on final follow-up radiographs, which is higher than what has been reported in the literature. In our practice, we now use a buttress plate and more recently have eliminated postoperative osteotomy displacement. Level IV, retrospective case series. © The Author(s) 2016.

Medial-row failure after arthroscopic double-row rotator cuff repair.

PubMed

Yamakado, Kotaro; Katsuo, Shin-ichi; Mizuno, Katsunori; Arakawa, Hitoshi; Hayashi, Seigaku

2010-03-01

We report 4 cases of medial-row failure after double-row arthroscopic rotator cuff repair (ARCR) without arthroscopic subacromial decompression (ASAD), in which there was pullout of mattress sutures of the medial row and knots were caught between the cuff and the greater tuberosity. Between October 2006 and January 2008, 49 patients underwent double-row ARCR. During this period, ASAD was not performed with ARCR. Revision arthroscopy was performed in 8 patients because of ongoing symptoms after the index operation. In 4 of 8 patients the medial rotator cuff failed; the tendon appeared to be avulsed at the medial row, and there were exposed knots on the bony surface of the rotator cuff footprint. It appeared that the knots were caught between the cuff and the greater tuberosity. Three retear cuffs were revised with the arthroscopic transtendon technique, and one was revised with a single-row technique after completing the tear. ASAD was performed in all patients. Three of the four patients showed improvement of symptoms and returned to their preinjury occupation. Impingement of pullout knots may be a source of pain after double-row rotator cuff repair. Copyright 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Computed Tomographic Distinction of Intimal and Medial Calcification in the Intracranial Internal Carotid Artery.

PubMed

Kockelkoren, Remko; Vos, Annelotte; Van Hecke, Wim; Vink, Aryan; Bleys, Ronald L A W; Verdoorn, Daphne; Mali, Willem P Th M; Hendrikse, Jeroen; Koek, Huiberdina L; de Jong, Pim A; De Vis, Jill B

2017-01-01

Intracranial internal carotid artery (iICA) calcification is associated with stroke and is often seen as a proxy of atherosclerosis of the intima. However, it was recently shown that these calcifications are predominantly located in the tunica media and internal elastic lamina (medial calcification). Intimal and medial calcifications are thought to have a different pathogenesis and clinical consequences and can only be distinguished through ex vivo histological analysis. Therefore, our aim was to develop CT scoring method to distinguish intimal and medial iICA calcification in vivo. First, in both iICAs of 16 cerebral autopsy patients the intimal and/or medial calcification area was histologically assessed (142 slides). Brain CT images of these patients were matched to the corresponding histological slides to develop a CT score that determines intimal or medial calcification dominance. Second, performance of the CT score was assessed in these 16 patients. Third, reproducibility was tested in a separate cohort. First, CT features of the score were circularity (absent, dot(s), <90°, 90-270° or 270-360°), thickness (absent, ≥1.5mm, or <1.5mm), and morphology (indistinguishable, irregular/patchy or continuous). A high sum of features represented medial and a lower sum intimal calcifications. Second, in the 16 patients the concordance between the CT score and the dominant calcification type was reasonable. Third, the score showed good reproducibility (kappa: 0.72 proportion of agreement: 0.82) between the categories intimal, medial or absent/indistinguishable. The developed CT score shows good reproducibility and can differentiate reasonably well between intimal and medial calcification dominance in the iICA, allowing for further (epidemiological) studies on iICA calcification.

Preoperative Patellofemoral Chondromalacia is Not a Contraindication for Fixed-Bearing Medial Unicompartmental Knee Arthroplasty.

PubMed

Adams, Alexander J; Kazarian, Gregory S; Lonner, Jess H

2017-06-01

Patellofemoral chondromalacia (PFCM) has historically been considered a contraindication for unicompartmental knee arthroplasty (UKA), but there is limited data assessing PFCM's impact on the results of fixed-bearing UKA. Our objective was to assess the impact of medial patellar and/or medial trochlear PFCM on overall and patellofemoral-specific 2-year outcomes after fixed-bearing medial UKA. Intraoperative notes defined the presence and location of PFCM during fixed bearing medial UKA. Outcome measures included the New Knee Society Score (NKSS), Kneeling Ability Score (KAS) and Forgotten Joint Score (FJS-12). Thirty-one knees with PFCM (PFCM group), and 52 knees without PFCM (N-PFCM group) were included for analysis. Mann-Whitney U tests assessed the statistical significance of observed differences, and a Bonferroni correction was applied, adjusting threshold for significance to P = .005. At minimum follow-up of 2 years, no statistical differences were detected between the N-PFCM and PFCM groups in the postoperative NKSS (159 vs 157, P = .731), preoperative to postoperative NKSS change (P = .447), FJS-12 (70.5 vs 67.6, P = .471), or KAS (71% vs 65%, P = .217). Patients with isolated patellar chondromalacia (n = 13) demonstrated trends toward worse outcomes according to NKSS (147, P = .198), FJS-12 (58, P = .094), and KAS (46%, P = .018), but were statistically insignificant. No failures occurred in either group. Functional outcomes of fixed-bearing medial UKA are not adversely impacted by the presence of PFCM involving the medial patellar facet and/or medial or central trochlea. Further follow-up is needed to determine longer-term implications of fixed-bearing medial UKA in patients with PFCM. Copyright © 2017 Elsevier Inc. All rights reserved.

Technique for CT Fluoroscopy-Guided Lumbar Medial Branch Blocks and Radiofrequency Ablation.

PubMed

Amrhein, Timothy J; Joshi, Anand B; Kranz, Peter G

2016-09-01

The purpose of this study is to describe the procedure for CT fluoroscopy-guided lumbar medial branch blocks and facet radiofrequency ablation. CT fluoroscopic guidance allows more-precise needle tip positioning and is an alternative method for performing medial branch blocks and facet radiofrequency ablation.

The JCR:LA-cp rat: a novel rodent model of cystic medial necrosis.

PubMed

Pung, Yuh Fen; Chilian, William M; Bennett, Martin R; Figg, Nichola; Kamarulzaman, Mohd Hamzah

2017-03-01

Although there are multiple rodent models of the metabolic syndrome, very few develop vascular complications. In contrast, the JCR:LA-cp rat develops both metabolic syndrome and early atherosclerosis in predisposed areas. However, the pathology of the normal vessel wall has not been described. We examined JCR:LA control (+/+) or cp/cp rats fed normal chow diet for 6 or 18 mo. JCR:LA-cp rats developed multiple features of advanced cystic medial necrosis including "cysts," increased collagen formation and proteoglycan deposition around cysts, apoptosis of vascular smooth muscle cells, and spotty medial calcification. These appearances began within 6 mo and were extensive by 18 mo. JCR:LA-cp rats had reduced medial cellularity, increased medial thickness, and vessel hypoxia that was most marked in the adventitia. In conclusion, the normal chow-fed JCR:LA-cp rat represents a novel rodent model of cystic medial necrosis, associated with multiple metabolic abnormalities, vascular smooth muscle cell apoptosis, and vessel hypoxia. NEW & NOTEWORTHY Triggers for cystic medial necrosis (CMN) have been difficult to study due to lack of animal models to recapitulate the pathologies seen in humans. Our study is the first description of CMN in the rat. Thus the JCR:LA-cp rat represents a useful model to investigate the underlying molecular changes leading to the development of CMN. Copyright © 2017 the American Physiological Society.

Recall and recognition of verbal paired associates in early Alzheimer's disease.

PubMed

Lowndes, G J; Saling, M M; Ames, D; Chiu, E; Gonzalez, L M; Savage, G R

2008-07-01

The primary impairment in early Alzheimer's disease (AD) is encoding/consolidation, resulting from medial temporal lobe (MTL) pathology. AD patients perform poorly on cued-recall paired associate learning (PAL) tasks, which assess the ability of the MTLs to encode relational memory. Since encoding and retrieval processes are confounded within performance indexes on cued-recall PAL, its specificity for AD is limited. Recognition paradigms tend to show good specificity for AD, and are well tolerated, but are typically less sensitive than recall tasks. Associate-recognition is a novel PAL task requiring a combination of recall and recognition processes. We administered a verbal associate-recognition test and cued-recall analogue to 22 early AD patients and 55 elderly controls to compare their ability to discriminate these groups. Both paradigms used eight arbitrarily related word pairs (e.g., pool-teeth) with varying degrees of imageability. Associate-recognition was equally effective as the cued-recall analogue in discriminating the groups, and logistic regression demonstrated classification rates by both tasks were equivalent. These preliminary findings provide support for the clinical value of this recognition tool. Conceptually it has potential for greater specificity in informing neuropsychological diagnosis of AD in clinical samples but this requires further empirical support.

Altered medial temporal activation related to local glutamate levels in subjects with prodromal signs of psychosis.

PubMed

Valli, Isabel; Stone, James; Mechelli, Andrea; Bhattacharyya, Sagnik; Raffin, Marie; Allen, Paul; Fusar-Poli, Paolo; Lythgoe, David; O'Gorman, Ruth; Seal, Marc; McGuire, Philip

2011-01-01

Both medial temporal cortical dysfunction and perturbed glutamatergic neurotransmission are regarded as fundamental pathophysiological features of psychosis. However, although animal models of psychosis suggest that these two abnormalities are interrelated, their relationship in humans has yet to be investigated. We used a combination of functional magnetic resonance imaging and magnetic resonance spectroscopy to investigate the relationship between medial temporal activation during an episodic memory task and local glutamate levels in 22 individuals with an at-risk mental state for psychosis and 14 healthy volunteers. We observed a significant between-group difference in the coupling of medial temporal activation with local glutamate levels. In control subjects, medial temporal activation during episodic encoding was positively associated with medial temporal glutamate. However, in the clinical population, medial temporal activation was reduced, and the relationship with glutamate was absent. In individuals at high risk of psychosis, medial temporal dysfunction seemed related to a loss of the normal relationship with local glutamate levels. This study provides the first evidence that links medial temporal dysfunction with the central glutamate system in humans and is consistent with evidence that drugs that modulate glutamatergic transmission might be useful in the treatment of psychosis. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

What to do with medialized tympanostomy tubes? A survey of pediatric otolaryngologists.

PubMed

Bezdjian, Aren; Jiang, Joanna; Maby, Alexandra; Daniel, Sam J

2018-01-01

Tympanostomy tube placement is the most common surgical procedure performed in children. Medial migration of a tympanostomy tube is a rare occurrence where the tube migrates into the middle ear cavity as opposed to its normal extrusion into the external auditory canal. Whether medialized tympanostomy tubes should be surgically removed in asymptomatic patients is controversial. The objective of this study was to determine experience and management approach of medialized tympanostomy tubes among pediatric otolaryngologists. A 12-question cross-section survey was designed and distributed to the American Society of Pediatric Otolaryngology (ASPO) members. The survey study was granted McGill University institutional review board and ASPO research committee approval. The survey data were filtered and cross-tabulated. Descriptive statistics were generated. 128 pediatric otolaryngologists completed the 12-question survey. The majority of respondents had experienced at least one case of medialized tympanostomy tube (90.6%). The majority of patients (82.0%) were asymptomatic. 74 out of 128 respondents (57.8%) indicated that they would not remove a medialized tube in an asymptomatic patient. However, 7.0% of those respondents clarified that they would proceed to surgical removal if the patient were undergoing general anesthesia for another surgery. 30.5% of respondents indicated that they would surgically remove the tube even if the patient were asymptomatic. 6.3% of respondents indicated that opted management in children would be based on a shared decision with parents. Most respondents (80.5%) did not experience complications with surgical removal nor with elected observation. There is no consensus among pediatric otolaryngologists regarding the necessity of surgically removing a medialized tympanostomy tube in asymptomatic patients. The survey suggests that both options are acceptable. If observation is chosen, it is important that parents are well informed of the

Medial gastrocnemius myoelectric control of a robotic ankle exoskeleton.

PubMed

Kinnaird, Catherine R; Ferris, Daniel P

2009-02-01

A previous study from our laboratory showed that when soleus electromyography was used to control the amount of plantar flexion assistance from a robotic ankle exoskeleton, subjects significantly reduced their soleus activity to quickly return to normal gait kinematics. We speculated that subjects were primarily responding to the local mechanical assistance of the exoskeleton rather than directly attempting to reduce exoskeleton mechanical power via decreases in soleus activity. To test this observation we studied ten healthy subjects walking on a treadmill at 1.25 m/s while wearing a robotic exoskeleton proportionally controlled by medial gastrocnemius activation. We hypothesized that subjects would primarily decrease soleus activity due to its synergistic mechanics with the exoskeleton. Subjects decreased medial gastrocnemius recruitment by 12% ( p < 0.05 ) but decreased soleus recruitment by 27% ( p < 0.05). In agreement with our hypothesis, the primary reduction in muscle activity was not for the control muscle (medial gastrocnemius) but for the anatomical synergist to the exoskeleton (soleus). These findings indicate that anatomical morphology needs to be considered carefully when designing software and hardware for robotic exoskeletons.

Case report: comprehensive management of medial tibial stress syndrome

PubMed Central

Krenner, Bernard John

2002-01-01

Abstract Activity or exercise-induced leg pain is a common complication among competitive and “weekend warrior” athletes. Shin splints is a term that has been used to describe all lower leg pain as a result of activity. There are many different causes of “shin splints,” one of which is medial tibial stress syndrome, and the treating clinician must be aware of potentially serious causes of activity related leg pain. Restoring proper biomechanics to the entire kinetic chain and rehabilitation of the injured area should be the primary aim of treatment to optimize shock absorption. The role inflammation plays in medial tibial stress syndrome is controversial, but in this case, seemed to be a causative factor as symptomatology was dramatically decreased with the addition of proteolytic enzymes. Medial tibial stress syndrome can be quite difficult to treat and keeping athletes away from activities that will slow healing or aggravate the condition can be challenging. “Active” rest is the best way in which to allow proper healing while allowing the athlete to maintain their fitness. PMID:19674573

Medial prefrontal cortex supports source memory for self-referenced materials in young and older adults

PubMed Central

Leshikar, Eric D.; Duarte, Audrey

2013-01-01

Behavioral evidence suggests that young and older adults show a benefit in source memory accuracy when processing materials in reference to the self. In the young, activity within the medial prefrontal cortex supports this source memory benefit at study. This investigation examined whether the same neural regions support this memory benefit in both age groups. Using fMRI, participants were scanned while studying and retrieving pictures of objects paired with one of three scenes (source) under self-reference and other-reference conditions. At the time of study, half of the items were presented once and half twice, allowing us to match behavioral performance between groups. Both groups showed equivalent source accuracy benefit for objects encoded self-referentially. Activity in the left dorsal medial prefrontal cortex supported subsequent source memory in both age groups for the self-referenced relative to the other-referenced items. At the time of test, source accuracy for both self- and other-referenced items was supported by a network of regions including the precuneus in both age groups. At both study and test, little in the way of age-differences emerged, suggesting that when matched on behavioral performance young and older adults engage similar regions in support of source memory when processing materials in reference to the self; however, when performance was not matched, age differences in functional recruitment were prevalent. These results suggest that by capitalizing on preserved processes (self-referential encoding), older adults can show improvement in memory for source details which typically are not well remembered relative to the young. PMID:23904335

Posterior medial meniscus-femoral insertion into the anterior cruciate ligament. A case report.

PubMed

Bhargava, A; Ferrari, D A

1998-03-01

Medial meniscal anomalies are rare. The anterior horn insertion into the anterior cruciate ligament is the most common. In the course of an arthroscopy for torn lateral meniscus, an anomalous band in continuity with the posterior horn of the medial meniscus was observed to insert into the anterior cruciate ligament. Although the tibial portion of the anterior cruciate was redundant, the anomalous band provided tension to the anterior cruciate ligament and a negative pivot shift. A previously unreported posterior medial meniscal femoral insertion is described.

Different roles of the medial and lateral hamstrings in unloading the anterior cruciate ligament.

PubMed

Guelich, David R; Xu, Dali; Koh, Jason L; Nuber, Gordon W; Zhang, Li-Qun

2016-01-01

Anterior cruciate ligament injuries are closely associated with excessive loading and motion about the off axes of the knee, i.e. tibial rotation and knee varus/valgus. However, it is not clear about the 3-D mechanical actions of the lateral and medial hamstring muscles and their differences in loading the ACL. The purpose of this study was to investigate the change in anterior cruciate ligament strain induced by loading the lateral and medial hamstrings individually. Seven cadaveric knees were investigated using a custom testing apparatus allowing for six degree-of-freedom tibiofemoral motion induced by individual muscle loading. With major muscles crossing the knee loaded moderately, the medial and lateral hamstrings were loaded independently to 200N along their lines of actions at 0°, 30°, 60° and 90° of knee flexion. The induced strain of the anterior cruciate ligament was measured using a differential variable reluctance transducer. Tibiofemoral kinematics was monitored using a six degrees-of-freedom knee goniometer. Loading the lateral hamstrings induced significantly more anterior cruciate ligament strain reduction (mean 0.764 [SD 0.63] %) than loading the medial hamstrings (mean 0.007 [0.2] %), (P=0.001 and effect size=0.837) across the knee flexion angles. The lateral and medial hamstrings have significantly different effects on anterior cruciate ligament loadings. More effective rehabilitation and training strategies may be developed to strengthen the lateral and medial hamstrings selectively and differentially to reduce anterior cruciate ligament injury and improve post-injury rehabilitation. The lateral and medial hamstrings can potentially be strengthened selectively and differentially as a more focused rehabilitation approach to reduce ACL injury and improve post-injury rehabilitation. Different ACL reconstruction procedures with some of them involving the medial hamstrings can be compared to each other for their effect on ACL loading. Copyright �

Tibiofemoral contact mechanics after serial medial meniscectomies in the human cadaveric knee.

PubMed

Lee, Stephen J; Aadalen, Kirk J; Malaviya, Prasanna; Lorenz, Eric P; Hayden, Jennifer K; Farr, Jack; Kang, Richard W; Cole, Brian J

2006-08-01

There is no consensus regarding the extent of meniscectomy leading to deleterious effects on tibiofemoral contact mechanics. The meniscus aids in optimizing tibiofemoral contact mechanics, increasing contact area, and decreasing contact stress. Controlled laboratory study. Twelve fresh-frozen human cadaveric knees each underwent 15 separate testing conditions-5 serial 20-mm posterior medial meniscectomy conditions (intact, 50% radial width, 75% radial width, segmental, and total meniscectomy) at 3 flexion angles (0 degrees , 30 degrees , and 60 degrees )-under an 1800-N axial load. Tekscan sensors were used to measure total force and medial force, contact area, mean contact stress, and peak contact stress. All posterior medial meniscectomy conditions resulted in significantly decreased contact areas and increased mean and peak contact stresses compared with the intact state (P < .05). The changes in contact mechanics after segmental and total posterior medial meniscectomies were not statistically different (P > .05). Incremental changes in contact area and mean contact stress increased as more peripheral portions of the medial meniscus were removed, whereas peak contact stresses exhibited similar incremental changes throughout all meniscectomy conditions. The meniscus is a crucial load-bearing structure, optimizing contact area and minimizing contact stress. Loss of hoop tension (ie, segmental meniscectomy) is equivalent to total meniscectomy in load-bearing terms. The peripheral portion of the medial meniscus provides a greater contribution to increasing contact areas and decreasing mean contact stresses than does the central portion, whereas peak contact stresses increase proportionally to the amount of meniscus removed. Because the degree of meniscectomy leading to clinically significant outcomes is unknown, a prudent strategy is to preserve the greatest amount of meniscus possible.

The figure-of-eight radix nasi flap for medial canthal defects.

PubMed

Seyhan, Tamer

2010-09-01

Basal cell carcinomas commonly involve the medial canthal region and reconstruction of medial canthal defects is a challenging problem in reconstructive surgery. A new axial pattern flap raised from radix nasi region has been successfully used for the medial canthal defects in eight patients in figure-of-eight manner. One of the ellipses of the figure of eight is the defect, the other is the radix nasi flap. The radix nasi flap with a dimension up to 25 mm is transposed to the defect based either on ipsilateral anastomosis of the dorsal nasal artery with angular artery (AA) or with the connection of its source artery (i.e. ophthalmic artery) if the AA is damaged. All flaps survived and no tumour recurrence was observed. The donor sites were closed primarily and hidden at the radix nasi crease in all cases. The radix nasi flap in figure-of-eight fashion is good alternative for defects of the medial canthal area in terms of attaining a suitable colour and texture and minimal surgical scars. Copyright 2009 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

A giraffe neck sign of the medial meniscus: A characteristic finding of the medial meniscus posterior root tear on magnetic resonance imaging.

PubMed

Furumatsu, Takayuki; Fujii, Masataka; Kodama, Yuya; Ozaki, Toshifumi

2017-07-01

The posterior root ligament of the medial meniscus (MM) has a critical role in regulating the MM movement. An accurate diagnosis of the MM posterior root tear (MMPRT) using magnetic resonance imaging (MRI) is important for preventing sequential osteoarthritis following the MMPRT. However, diagnosis of the MMPRT is relatively difficult even after using several characteristic MRI findings. The aim of this study was to identify a useful meniscal body sign of the MMPRT for improving diagnostic MRI reading. Eighty-five patients who underwent surgical treatments for the MMPRT (39 knees) and other types of MM tears (49 knees) were included. The presence of characteristic MRI findings such as cleft sign, ghost sign, radial tear sign, medial extrusion sign, and new meniscal body shape-oriented "giraffe neck sign" was evaluated in 120 MRI examinations. Giraffe neck signs were observed in 81.7% of the MMPRTs and in 3.3% of other MM tears. Cleft, ghost, and radial tear signs were highly positive in the MMPRTs compared with other MM tears. Medial extrusion signs were frequently observed in both groups. Coexistence rates of any 2 MRI signs, except for medial extrusion sign, were 91.7% in the MMPRT group and 5% in other MM tears. This study demonstrated that a new characteristic MRI finding "giraffe neck sign" was observed in 81.7% of the MMPRT. Our results suggest that the combination of giraffe neck, cleft, ghost, and radial tear signs may be important for an accurate diagnostic MRI reading of the MMPRT. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Proximally pedicled medial plantar flap based on superficial venous system alone for venous drainage.

PubMed

Wright, Thomas C; Mossaad, Bassem M; Chummun, Shaheel; Khan, Umraz; Chapman, Thomas W L

2013-07-01

The proximally pedicled medial plantar flap is well described for coverage of wounds around the ankle and heel. This flap is usually based on the deep venae comitantes for venous drainage, with the superficial veins divided during dissection. Usually any disruption of the deep venous system of the flap would result in abandoning this choice of flap. Venous congestion is a recognised complication of medial plantar flaps. The patient described in this case report had a medial ankle defect with exposed bone, for which a proximally pedicled medial plantar flap was used. As we raised the flap, both venae comitantes of the medial planter artery were found to be disrupted. The flap was raised based on the superficial veins draining into the great saphenous, as the only system for venous drainage, with no evidence of venous congestion. The flap was successfully transposed into the defect and healed with no complications. The proximally pedicled medial plantar flap can safely rely on the superficial venous system alone for drainage. In addition, preserving the superficial veins minimise the risk of venous congestion in this flap. We recommend preservation of superficial venous system when possible. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Novel air-injection technique to locate the medial cut end of lacerated canaliculus.

PubMed

Liu, Bingqian; Li, Yonghao; Long, Chongde; Wang, Zhonghao; Liang, Xuanwei; Ge, Jian; Wang, Zhichong

2013-12-01

Locating the medial cut end of the severed canaliculus is the most difficult aspect of canalicular repair, especially in patients with more medial laceration, severe oedema, persistent errhysis and a narrow canaliculus. Irrigation is a widely used technique to identify the cut end; however, we found that air injected through the intact canaliculus with a straight needle failed to reflux when the common canaliculus or lacrimal sac was not blocked. We describe a simple, safe and efficient air-injection technique to identify the medial cut edge of a lacerated canaliculus. In this method, we initially submersed the medial canthus under normal saline, then injected filtered air through the intact canaliculus using a side port stainless steel probe with a closed round tip. The tip was designed to block the common canaliculus to form a relatively closed system. The efficiency of this novel air-injection technique was equivalent to the traditional technique but does not require the cooperation of the patient to blow air. Using this technique, the medial cut end was successfully identified by locating the air-bubble exit within minutes in 19 cases of mono-canalicular laceration without any complication.

[A case of bilateral medial medullary infarction caused by unilateral vertebral artery dissection].

PubMed

Akimoto, Takayoshi; Hara, Makoto; Saito, Mari; Takahashi, Keiko; Kamei, Satoshi

2015-01-01

A 34-year-old man developed right neck pain. Several hours later, he felt numbness of his extremities and presented at our hospital. He developed right hemiparesis and hypoesthesia of the right extremities. A few hours later, upbeat nystagmus and dysarthria appeared along with a sensory disturbance that spread to all extremities, and right hemiparesis progressed to tetraplegia. Brain MR diffusion-weighted images revealed a high-intensity lesion in the bilateral medial medulla oblongata and we diagnosed this bilateral medial medullary infarction. Three dimentional CT angiography revealed dissection of the right VA. We administered intravenous argatroban, edaravone, glycerin and oral clopidogrel. He was assessed as having modified Rankin scale 4 and was transferred to another hospital for rehabilitation on day 30. When the medial medulla oblongata is supplied by the unilateral VA, a unilateral VA dissection can cause bilateral medial medullary infarction.

Medial joint line bone bruising at MRI complicating acute ankle inversion injury: what is its clinical significance?

PubMed

Chan, V O; Moran, D E; Shine, S; Eustace, S J

2013-10-01

To assess the incidence and clinical significance of medial joint line bone bruising following acute ankle inversion injury. Forty-five patients who underwent ankle magnetic resonance imaging (MRI) within 2 weeks of acute ankle inversion injury were included in this prospective study. Integrity of the lateral collateral ligament complex, presence of medial joint line bone bruising, tibio-talar joint effusion, and soft-tissue swelling were documented. Clinical follow-up at 6 months was carried out to determine the impact of injury on length of time out of work, delay in return to normal walking, delay in return to sports activity, and persistence of medial joint line pain. Thirty-seven patients had tears of the anterior talofibular ligament (ATFL). Twenty-six patients had medial joint line bone bruising with altered marrow signal at the medial aspect of the talus and congruent surface of the medial malleolus. A complete ATFL tear was seen in 92% of the patients with medial joint line bone bruising (p = 0.05). Patients with an ATFL tear and medial joint line bone bruising had a longer delay in return to normal walking (p = 0.0002), longer delay in return to sports activity (p = 0.0001), and persistent medial joint line pain (p = 0.0003). There was no statistically significant difference in outcome for the eight patients without ATFL tears. Medial joint line bone bruising following an acute ankle inversion injury was significantly associated with a complete ATFL tear, longer delay in the return to normal walking and sports activity, as well as persistent medial joint line pain. Its presence should prompt detailed assessment of the lateral collateral ligament complex, particularly the ATFL. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Usefulness of StereoEEG-based tailored surgery for medial temporal lobe epilepsy. Preliminary results in 11 patients.

PubMed

Kubota, Yuichi; Ochiai, Taku; Hori, Tomokatsu; Kawamata, Takakazu

2017-07-01

Surgical options for medial temporal lobe epilepsy (MTLE) include anterior temporal lobectomy (ATL) and selective amygdalohippocampectomy (SAH). Optimal criteria for choosing the appropriate surgical approach remain uncertain. This article reports 11 consecutive cases in which electrophysiological findings of stereoelectroencephalography (SEEG) were used to determine the optimal surgical approach. Eleven consecutive patients with MTLE underwent SEEG evaluation and were placed in either the medial or the medial+lateral group based on the findings. Patients in the medial group underwent SAH using the subtemporal approach, and patients in the medial+lateral group underwent SEEG-guided anterior temporal lobectomy. SEEG findings were also compared with other examinations including flumazenil (FMZ)-positron emission tomography (PET), fluorine-18 labeled fluorodeoxyglucose (FDG)-PET, and magnetoencephalography (MEG). Results were evaluated to determine which examinations most consistently identified the epileptogenic zone. Of the 11 cases, 4 patients were placed in the medial group, and 7 patients in the medial+lateral group. Of patients, 90.9% were classified in class I of the Engel Epilepsy Surgery Outcome Scale, while 72.7% were classified in class I by the International League Against Epilepsy (ILAE) system. Analyzed by group, 100% of the medial group experienced an Engel class I outcome in the medial group, compared to 85.7% in the medial+lateral group. SEEG findings were comparable with FDG-PET results (10 of 11, 91%). Tailored surgery guided by SEEG is an electrophysiologically feasible treatment for MTLE that can result in favorable outcomes. Although seizures are thought to originate in the medial temporal lobe in MTLE, it is important for involvement of the lateral temporal cortex to be also considered in some cases. Copyright © 2017. Published by Elsevier B.V.

Medial Orbitofrontal Neurons Preferentially Signal Cues Predicting Changes in Reward during Unblocking

PubMed Central

Lopatina, Nina; McDannald, Michael A.; Styer, Clay V.; Peterson, Jacob F.; Sadacca, Brian F.; Cheer, Joseph F.

2016-01-01

The orbitofrontal cortex (OFC) has been broadly implicated in the ability to use the current value of expected outcomes to guide behavior. Although value correlates have been prominently reported in lateral OFC, they are more often associated with more medial areas. Further, recent studies in primates have suggested a dissociation in which the lateral OFC is involved in credit assignment and representation of reward identity and more medial areas are critical to representing value. Previously, we used unblocking to test more specifically what information about outcomes is represented by OFC neurons in rats; consistent with the proposed dichotomy between the lateral and medial OFC, we found relatively little linear value coding in the lateral OFC (Lopatina et al., 2015). Here we have repeated this experiment, recording in the medial OFC, to test whether such value signals might be found there. Neurons were recorded in an unblocking task as rats learned about cues that signaled either more, less, or the same amount of reward. We found that medial OFC neurons acquired responses to these cues; however, these responses did not signal different reward values across cues. Surprisingly, we found that cells developed responses to cues predicting a change, particularly a decrease, in reward value. This is consistent with a special role for medial OFC in representing current value to support devaluation/revaluation sensitive changes in behavior. SIGNIFICANCE STATEMENT This study uniquely examines encoding in rodent mOFC at the single-unit level in response to cues that predict more, less, or no change in reward in rats during training in a Pavlovian unblocking task, finding more cells responding to change-predictive cues and stronger activity in response to cues predictive of less reward. PMID:27511013

Pick a Pair. Pancake Pairs

ERIC Educational Resources Information Center

Miller, Pat

2005-01-01

Cold February weather and pancakes are a traditional pairing. Pancake Day began as a way to eat up the foods that were abstained from in Lent--traditionally meat, fat, eggs and dairy products. The best-known pancake event is The Pancake Day Race in Buckinghamshire, England, which has been run since 1445. This column describes pairs of books that…

GABAergic Projections from the Medial Septum Selectively Inhibit Interneurons in the Medial Entorhinal Cortex

PubMed Central

Gonzalez-Sulser, Alfredo; Parthier, Daniel; Candela, Antonio; McClure, Christina; Pastoll, Hugh; Garden, Derek; Sürmeli, Gülşen

2014-01-01

The medial septum (MS) is required for theta rhythmic oscillations and grid cell firing in the medial entorhinal cortex (MEC). While GABAergic, glutamatergic, and cholinergic neurons project from the MS to the MEC, their synaptic targets are unknown. To investigate whether MS neurons innervate specific layers and cell types in the MEC, we expressed channelrhodopsin-2 in mouse MS neurons and used patch-clamp recording in brain slices to determine the response to light activation of identified cells in the MEC. Following activation of MS axons, we observed fast monosynaptic GABAergic IPSPs in the majority (>60%) of fast-spiking (FS) and low-threshold-spiking (LTS) interneurons in all layers of the MEC, but in only 1.5% of nonstellate principal cells (NSPCs) and in no stellate cells. We also observed fast glutamatergic responses to MS activation in a minority (<5%) of NSPCs, FS, and LTS interneurons. During stimulation of MS inputs at theta frequency (10 Hz), the amplitude of GABAergic IPSPs was maintained, and spike output from LTS and FS interneurons was entrained at low (25–60 Hz) and high (60–180 Hz) gamma frequencies, respectively. By demonstrating cell type-specific targeting of the GABAergic projection from the MS to the MEC, our results support the idea that the MS controls theta frequency activity in the MEC through coordination of inhibitory circuits. PMID:25505326

LOCAL ORTHOGONAL CUTTING METHOD FOR COMPUTING MEDIAL CURVES AND ITS BIOMEDICAL APPLICATIONS

PubMed Central

Einstein, Daniel R.; Dyedov, Vladimir

2010-01-01

Medial curves have a wide range of applications in geometric modeling and analysis (such as shape matching) and biomedical engineering (such as morphometry and computer assisted surgery). The computation of medial curves poses significant challenges, both in terms of theoretical analysis and practical efficiency and reliability. In this paper, we propose a definition and analysis of medial curves and also describe an efficient and robust method called local orthogonal cutting (LOC) for computing medial curves. Our approach is based on three key concepts: a local orthogonal decomposition of objects into substructures, a differential geometry concept called the interior center of curvature (ICC), and integrated stability and consistency tests. These concepts lend themselves to robust numerical techniques and result in an algorithm that is efficient and noise resistant. We illustrate the effectiveness and robustness of our approach with some highly complex, large-scale, noisy biomedical geometries derived from medical images, including lung airways and blood vessels. We also present comparisons of our method with some existing methods. PMID:20628546

Local Orthogonal Cutting Method for Computing Medial Curves and Its Biomedical Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiao, Xiangmin; Einstein, Daniel R.; Dyedov, Volodymyr

2010-03-24

Medial curves have a wide range of applications in geometric modeling and analysis (such as shape matching) and biomedical engineering (such as morphometry and computer assisted surgery). The computation of medial curves poses significant challenges, both in terms of theoretical analysis and practical efficiency and reliability. In this paper, we propose a definition and analysis of medial curves and also describe an efficient and robust method for computing medial curves. Our approach is based on three key concepts: a local orthogonal decomposition of objects into substructures, a differential geometry concept called the interior center of curvature (ICC), and integrated stabilitymore » and consistency tests. These concepts lend themselves to robust numerical techniques including eigenvalue analysis, weighted least squares approximations, and numerical minimization, resulting in an algorithm that is efficient and noise resistant. We illustrate the effectiveness and robustness of our approach with some highly complex, large-scale, noisy biomedical geometries derived from medical images, including lung airways and blood vessels. We also present comparisons of our method with some existing methods.« less

Radial tears associated with cleavage tears of the medial meniscus in athletes.

PubMed

Kidron, Amos; Thein, Rafael

2002-03-01

To evaluate the significance of a small radial tear in the root of the posterior horn of the medial meniscus in an otherwise normal-looking meniscus in individuals who play vigorous sports. Retrospective review. Arthroscopy was performed in 1,270 patients; 11 patients (0.86%) had a small radial tear in the root of the medial meniscus. Trimming of the tear revealed a large horizontal cleavage tear of the posterior horn and body of the meniscus. The average age of the affected patients was 29.6 years (range, 21 to 45 years), and all were active in sports. Magnetic resonance imaging was of dubious diagnostic value. Three patients had undergone previous arthroscopy at which time the small radial root tear had been noted but was not thought to warrant treatment. All 11 patients returned to their former levels of activity after adequate surgery. When a radial root tear in the medial meniscus is found in an athletic patient, the edges of the tear should be trimmed, the root of the medial meniscus examined, and any additional torn cartilage resected.

Pediatric Glial Heterotopia in the Medial Canthus.

PubMed

Kim, Soung Min; Amponsah, Emmanuel Kofi; Eo, Mi Young; Cho, Yun Ju; Lee, Suk Keun

2017-11-01

Glial heterotopias are rare, benign, congenital, midline, and nonteratomatous extracranial glial tissue. They may be confused as encephalocele or dermoid cysts and are mostly present in the nose.An 8-month-old African female child presented with a slow growing paranasal mass. The mass had been present at the left upper medial canthus since birth and had slowly and progressively enlarged. There was no communication between the mass and the cranial cavity during the operational procedure. The mass was immunohistochemically positive for S-100 protein as well as for glial fibrillary acidic protein, but negative for proliferating cell nuclear antigen. This suggested that the mass was composed of benign glial tissues with many astrocytes.The purpose of this report is to demonstrate the first patient with pediatric glial heterotopic tissue in the medial canthus and to report the clinical importance of its immunohistochemical findings.

Axonal synapse sorting in medial entorhinal cortex

NASA Astrophysics Data System (ADS)

Schmidt, Helene; Gour, Anjali; Straehle, Jakob; Boergens, Kevin M.; Brecht, Michael; Helmstaedter, Moritz

2017-09-01

Research on neuronal connectivity in the cerebral cortex has focused on the existence and strength of synapses between neurons, and their location on the cell bodies and dendrites of postsynaptic neurons. The synaptic architecture of individual presynaptic axonal trees, however, remains largely unknown. Here we used dense reconstructions from three-dimensional electron microscopy in rats to study the synaptic organization of local presynaptic axons in layer 2 of the medial entorhinal cortex, the site of grid-like spatial representations. We observe path-length-dependent axonal synapse sorting, such that axons of excitatory neurons sequentially target inhibitory neurons followed by excitatory neurons. Connectivity analysis revealed a cellular feedforward inhibition circuit involving wide, myelinated inhibitory axons and dendritic synapse clustering. Simulations show that this high-precision circuit can control the propagation of synchronized activity in the medial entorhinal cortex, which is known for temporally precise discharges.

Efficacy and Safety of a Novel Three-Step Medial Release Technique in Varus Total Knee Arthroplasty.

PubMed

Kim, Min Woo; Koh, In Jun; Kim, Ju Hwan; Jung, Jae Jong; In, Yong

2015-09-01

We investigated the efficacy and safety of our novel three-step medial release technique in varus total knee arthroplasty (TKA) over time. Two hundred sixty seven consecutive varus TKAs were performed by applying the algorithmic release technique which consisted of sequential release of the deep medial collateral ligament (step 1), the semimembranosus (step 2), and multiple needle puncturing of the superficial medial collateral ligament (step 3). One hundred seventeen, 114, and 36 knees were balanced after step 1, 2, and 3 releases, respectively. There were no significant differences in changes of medial and lateral laxities between groups in over a year. Our novel stepwise medial release technique was efficacious and safe in balancing varus knees during TKA. Copyright © 2015 Elsevier Inc. All rights reserved.

Isolated medial meniscal tear in a Border Collie.

PubMed

Ridge, P A

2006-01-01

A three-year-old, female Border Collie was successfully treated for an isolated, torn, medial meniscus by arthroscopic meniscal tear resection. The dog returned to agility competition without recurrence of lameness.

Physical examination and imaging of medial collateral ligament and posteromedial corner of the knee.

PubMed

Craft, Jason A; Kurzweil, Peter R

2015-06-01

The medial collateral ligament (MCL) is the most commonly injured knee ligament. Most will heal well with nonoperative treatment. However, not all medial knee injuries are the same. A detailed physical examination can help determine the severity of the medial-sided injury. When combined with advanced imaging, the examination will delineate damage to associated medial knee structures, including the location of MCL damage, posteromedial capsule injuries, and combined cruciate injuries. Failure to recognize MCL injuries that may be prone to chronic laxity can lead to significant disability, joint damage, and failure of concomitant cruciate ligament reconstructions. Magnetic resonance imaging is the mainstay of diagnostic imaging, with coronal sequences allowing full assessment of the MCL complex. Tangential views aid in the diagnosis of concomitant injuries. Stress radiography can play a role in evaluating MCL healing and subtle chronic laxity. Ultrasonography is also gaining acceptance as a means to assess MCL injuries. Use of a detailed examination and advanced imaging will allow optimal treatment of medial knee injuries and improve clinical outcomes.

Contrasting medial moraine development at adjacent temperate, maritime glaciers: Fox and Franz Josef Glaciers, South Westland, New Zealand

NASA Astrophysics Data System (ADS)

Brook, Martin; Hagg, Wilfried; Winkler, Stefan

2017-08-01

Medial moraines form important pathways for sediment transportation in valley glaciers. Despite the existence of well-defined medial moraines on several glaciers in the New Zealand Southern Alps, medial moraines there have hitherto escaped attention. The evolving morphology and debris content of medial moraines on Franz Josef Glacier and Fox Glacier on the western flank of the Southern Alps is the focus of this study. These temperate maritime glaciers exhibit accumulation zones of multiple basins that feed narrow tongues flowing down steep valleys and terminate 400 m above sea level. The medial moraines at both glaciers become very prominent in the lower ablation zones, where the medial moraines widen, and develop steeper flanks coeval with an increase in relative relief. Medial moraine growth appears somewhat self-limiting in that relief and slope angle increase eventually lead to transport of debris away from the medial moraine by mass-movement-related processes. Despite similarities in overall morphologies, a key contrast in medial moraine formation exists between the two glaciers. At Fox Glacier, the medial moraine consists of angular rockfall-derived debris, folded to varying degrees along flow-parallel axes throughout the tongue. The debris originates above the ELA, coalesces at flow-unit boundaries, and takes a medium/high level transport pathway before subsequently emerging at point-sources aligned with gently dipping fold hinges near the snout. In contrast at Franz Josef Glacier, the medial moraine emerges farther down-glacier immediately below a prominent rock knob. Clasts show a mix of angular to rounded shapes representing high level transport and subglacially transported materials, the latter facies possibly also elevated by supraglacial routing of subglacial meltwater. Our observations confirm that a variety of different debris sources, transport pathways, and structural glaciological processes can interact to form medial moraines within New Zealand

Releasing the circumferential fixation of the medial meniscus does not affect its kinematics.

PubMed

Vrancken, A C T; van Tienen, T G; Hannink, G; Janssen, D; Verdonschot, N; Buma, P

2014-12-01

Meniscal functioning depends on the fixation between the meniscal horns and the surrounding tissues. It is unknown, however, whether the integration between the outer circumference of the medial meniscus and the knee capsule/medial collateral ligament also influences the biomechanical behavior of the meniscus. Therefore, we aimed to determine whether detaching and resuturing the circumferential fixation of the medial meniscus influence its kinematic pattern. Human cadaveric knee joints were flexed (0°-30°-60°-90°) in a knee loading rig, in neutral orientation and under internal and external tibial torques. Roentgen stereophotogrammetric analysis was used to determine the motion of the meniscus in anteroposterior (AP) and mediolateral (ML) directions. Three fixation conditions were evaluated: (I) intact, (II) detached and (III) resutured. Detaching and resuturing the circumferential fixation did not alter the meniscal motion pattern in either the AP or ML direction. Applying an additional internal tibial torque caused the medial meniscus to move slightly anteriorly, and an external torque caused a little posterior translation with respect to the neutral situation. These patterns did not change when the circumferential fixation condition was altered. This study demonstrated that the motion pattern of the medial meniscus is independent of its fixation to the knee capsule and medial collateral ligament. The outcomes of this study can be deployed to design the fixation strategy of a permanent meniscus prosthesis. As peripheral fixation is a complicated step during meniscal replacement, the surgical procedure is considerably simplified when non-resorbable implants do not require circumferential fixation. Copyright © 2014 Elsevier B.V. All rights reserved.

The operative outcomes of displaced medial-end clavicle fractures.

PubMed

Sidhu, Verinder S; Hermans, Deborah; Duckworth, David G

2015-11-01

Nonoperative treatment of displaced medial clavicle fractures often leads to poor functional outcomes and painful nonunions. This study investigates the functional outcomes of patients undergoing operative fixation of these fractures. We investigated 27 patients undergoing operative fixation of a medial clavicle fracture; 24 had an acute, displaced fracture and 3 had fixation for nonunions. Preoperative radiographs or computed tomography scans were obtained, and data collected included age, sex, mechanism of injury, and fixation method. Follow-up included physical examination and radiographs for assessment of union; Disabilities of the Arm, Shoulder, and Hand scores at 12 months; and the recording of complications. The median age was 37 years (interquartile range, 17-47 years). There were 26 male patients and one female patient included, with 7 physeal injuries and 20 adult injuries. The most common mechanism of fracture was vehicular accident (n = 15). Three patients had operations for nonunions and 2 for a periprosthetic fracture medial to an existing plate. The fracture was fixed with plate and screws in 19 cases and with transosseous sutures in 8 cases. The median Disabilities of the Arm, Shoulder, and Hand score at 12 months was 0.4 (interquartile range, 0-5.0), with a union rate of 100% at 12 months. All patients had full shoulder range of motion at final follow-up and were able to return to preinjury occupational activities. There were no significant complications. Operative fixation of displaced medial clavicle fractures results in anatomic reconstruction and excellent functional outcomes, even in the setting of fixation performed for symptomatic nonunion. Early intervention can minimize the risk of painful nonunion. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Differential effects of unilateral lesions in the medial amygdala on spontaneous and induced ovulation.

PubMed

Sanchez, M A; Dominguez, R

1995-01-01

The possible existence of asymmetry in the control of ovulation by the medial amygdala was explored. Unilateral lesions of the medial amygdala were performed on each day of the estrous cycle. The estral index diminished in almost all animals with a lesion in the right side of medial amygdala. Lesions of the right medial amygdala, when performed on diestrus-1, resulted in a significant decrease in the number of rats ovulating compared to controls (4/8 vs. 8/8, p < 0.05). In ovulating animals a significant reduction in the number of ova shed by the left ovary was found (2.2 +/- 0.8 vs. 6.3 +/- 0.8, p < 0.05). Lesions of the stria terminalis performed on diestrus-1 did not affect ovulation. In a second experiment, administration of GnRH did not restore ovulation in rats with lesions of the right medial amygdala. However, sequential injections of PMSG-hCG did result in ovulation by all members of a group of lesioned animals. In this last condition a significant decrease in the number of ova shed by the right ovary was found compared to animals in the lesion-only condition (1.5 +/- 0.5 vs. 6.0 +/- 1.5, p < 0.05). These data suggest that control of ovulation by the medial amygdala is asymmetric and varies during the estrous cycle.

Gender moderates the association between dorsal medial prefrontal cortex volume and depressive symptoms in a subclinical sample.

PubMed

Carlson, Joshua M; Depetro, Emily; Maxwell, Joshua; Harmon-Jones, Eddie; Hajcak, Greg

2015-08-30

Major depressive disorder is associated with lower medial prefrontal cortex volumes. The role that gender might play in moderating this relationship and what particular medial prefrontal cortex subregion(s) might be implicated is unclear. Magnetic resonance imaging was used to assess dorsal, ventral, and anterior cingulate regions of the medial prefrontal cortex in a normative sample of male and female adults. The Depression, Anxiety, and Stress Scale (DASS) was used to measure these three variables. Voxel-based morphometry was used to test for correlations between medial prefrontal gray matter volume and depressive traits. The dorsal medial frontal cortex was correlated with greater levels of depression, but not anxiety and stress. Gender moderates this effect: in males greater levels of depression were associated with lower dorsal medial prefrontal volumes, but in females no relationship was observed. The results indicate that even within a non-clinical sample, male participants with higher levels of depressive traits tend to have lower levels of gray matter volume in the dorsal medial prefrontal cortex. Our finding is consistent with low dorsal medial prefrontal volume contributing to the development of depression in males. Future longitudinal work is needed to substantiate this possibility. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Examination and treatment of a loose medial coronoid process in dogs].

PubMed

Hazewinkel, H A; Voorhout, G

1986-12-15

An ununited medial coronoid process (MCP) is the most common developmental disturbance in the elbow joint of young dogs of large and medium-sized breeds. The clinical and radiological symptoms of ununited medial coronoid processes in thirty-nine dogs are reported, the presence of an ununited medial coronoid process being established by arthrotomy in these cases. Lameness was observed for the first time in these dogs, mainly Rottweilers, Retrievers and Berner Sennenhunde, and more often male dogs than bitches, when they were from four to six months of age. They showed lameness ranging from slight to severe, and the leg was frequently held in a position of abduction and outward rotation. The elbow joints involved often showed abnormal accumulations of fluid, hyperflexion and/or hyperextension being painful. Osteophytes, only occurring along the proximal border of the anconeal process, could be well assessed on the mediolateral radiographs. The appearance of the MCP, varying from normal to ununited, could best be evaluated in the mediolateral and anteroposterior medial oblique radiographs. These two radiographs were also of value in diagnosing an ununited anconeal process which was present at the same time as osteochondrosis of the medial condyle of the humerus in two dogs. The clinical symptoms were not associated with radiologically perceptible changes in some cases. Arthrotomy of the elbows showed that the entire apex or otherwise one or several fragments of the MCP, which are often wedged between the radius and ulna in these cases, may break off. Rapid post-operative improvement of locomotion is frequently reported. Preventive and diagnostic procedures carried out to make possible early institution of surgical treatment are discussed.

Medial elbow injury in young throwing athletes

PubMed Central

Gregory, Bonnie; Nyland, John

2013-01-01

Summary This report reviews the anatomy, overhead throwing biomechanics, injury mechanism and incidence, physical examination and diagnosis, diagnostic imaging and conservative treatment of medial elbow injuries in young throwing athletes. Based on the information a clinical management decision-making algorithm is presented. PMID:23888291

Affective Aprosodia from a Medial Frontal Stroke

ERIC Educational Resources Information Center

Heilman, Kenneth M.; Leon, Susan A.; Rosenbek, John C.

2004-01-01

Background and objectives: Whereas injury to the left hemisphere induces aphasia, injury to the right hemisphere's perisylvian region induces an impairment of emotional speech prosody (affective aprosodia). Left-sided medial frontal lesions are associated with reduced verbal fluency with relatively intact comprehension and repetition…

Improved arthroscopic one-piece excision technique for the treatment of symptomatic discoid medial meniscus.

PubMed

Wang, Hong-De; Li, Tong; Gao, Shi-Jun

2017-10-30

Discoid medial meniscus is an extremely rare abnormality of the knee. During arthroscopic meniscectomy for symptomatic discoid medial meniscus, it is difficult to remove the posterior portion of the meniscus because of the confined working space within the compartment and the obstruction caused by the anterior cruciate ligament and the tibial intercondylar eminence. To overcome these problems, we describe an improved arthroscopic technique for one-piece excision of symptomatic discoid medial meniscus through three unique portals. Three improved portals were made in the injured knee: a standard anteromedial portal, a central transpatellar tendon portal, and a high anterolateral portal. The anterior side of the discoid medial meniscus was cut 7 mm from the periphery of the meniscus. Next, the anterior portion of the free discoid meniscus fragment was pulled in the anterolateral direction with tension. A curve-shaped cut was made along the longitudinal tear to the posterior horn using basket forceps through the standard anteromedial portal. Then, the anterior portion of the free discoid meniscus was pulled in the anteromedial direction. Pulling the fragment under tension made it easier to cut the posterior side of the discoid meniscus. The posterior side of the discoid meniscus was cut 7 mm from the periphery of the meniscus with straight scissors or basket forceps through the central transpatellar tendon portal. This technique resulted in satisfactory results. Excellent visualization of the posterior part of the discoid medial meniscus was gained during the procedure, and it was easy to cut the posterior part of the discoid medial meniscus. No recurrent symptoms were found. This improved arthroscopic one-piece excision technique for the treatment of symptomatic discoid medial meniscus enables the posterior part of the meniscus to be cut satisfactorily. Moreover, compared with previous techniques, this novel technique causes less formation of foreign bodies and less

Repair of the posterior root of the medial meniscus.

PubMed

Jones, Christopher; Reddy, Sudheer; Ma, C Benjamin

2010-01-01

Tears of the posterior root of the medial meniscus are becoming increasingly recognized. Early identification and treatment of these tears help halt the progression of cartilage degeneration and osteoarthritis of the knee. Repair of these tears is essential for recreating the hoop stress of the medial meniscus. In this note, we describe a successful arthroscopic technique to repair this lesion. A posteromedial portal is established by which two 2-0 PDS sutures are placed through the meniscus root and pulled down through a trans-tibial tunnel and fixed using an EndoButton distally along the anterolateral cortex of the tibia. This has been performed successfully in five patients with no complications.

Centromere pairing precedes meiotic chromosome pairing in plants.

PubMed

Zhang, Jing; Han, Fangpu

2017-11-01

Meiosis is a specialized eukaryotic cell division, in which diploid cells undergo a single round of DNA replication and two rounds of nuclear division to produce haploid gametes. In most eukaryotes, the core events of meiotic prophase I are chromosomal pairing, synapsis and recombination. To ensure accurate chromosomal segregation, homologs have to identify and align along each other at the onset of meiosis. Although much progress has been made in elucidating meiotic processes, information on the mechanisms underlying chromosome pairing is limited in contrast to the meiotic recombination and synapsis events. Recent research in many organisms indicated that centromere interactions during early meiotic prophase facilitate homologous chromosome pairing, and functional centromere is a prerequisite for centromere pairing such as in maize. Here, we summarize the recent achievements of chromosome pairing research on plants and other organisms, and outline centromere interactions, nuclear chromosome orientation, and meiotic cohesin, as main determinants of chromosome pairing in early meiotic prophase.

Recruitment of the Rhesus soleus and medial gastrocnemius before, during and after spaceflight

NASA Technical Reports Server (NTRS)

Roy, R. R.; Hodgson, J. A.; Aragon, J.; Day, M. K.; Kozlovskaya, I.; Edgerton, V. R.

1996-01-01

Electromyograms were recorded from the soleus and medial gastrocnemius muscles and tendon force from the medial gastrocnemius muscle of 2 juvenile Rhesus monkeys before, during and after Cosmos flight 2229 and of ground control animals. Recording sessions were made while the Rhesus were performing a foot pedal motor task. Preflight testing indicated normal patterns of recruitment between the soleus and medial gastrocnemius, i.e. a higher level of recruitment of the soleus compared to the medial gastrocnemius during the task. Recording began two days into the spaceflight and showed that the media gastrocnemius was recruited preferentially over the soleus. This observation persisted throughout the flight and for the 2 week period of postflight testing. These data indicate a significant change in the relative recruitment of slow and fast extensor muscles under microgravity conditions. The appearance of clonic-like activity in one muscle of each Rhesus during flight further suggests a reorganization in the neuromotor system in a microgravity environment.

Knotless double-row SutureBridge rotator cuff repairs have improved self-reinforcement compared with double-row SutureBridge repairs with tied medial knots: a biomechanical study using an ovine model.

PubMed

Smith, Geoffrey C S; Bouwmeester, Theresia M; Lam, Patrick H

2017-12-01

In double-row SutureBridge (Arthrex, Naples, FL, USA) rotator cuff repairs, increasing tendon load may generate progressively greater compression forces at the repair footprint (self-reinforcement). SutureBridge rotator cuff repairs using tied horizontal mattress sutures medially may limit this effect compared with a knotless construct. Rotator cuff repairs were performed in 9 pairs of ovine shoulders. One group underwent repair with a double-row SutureBridge construct with tied horizontal medial-row mattress sutures. The other group underwent repair in an identical fashion except that medial-row knots were not tied. Footprint contact pressure was measured at 0° and 20° of abduction under loads of 0 to 60 N. Pull-to-failure tests were then performed. In both repair constructs, each 10-N increase in rotator cuff tensile load led to a significant increase in footprint contact pressure (P < .0001). The rate of increase in footprint contact pressure was greater in the knotless construct (P < .00022; ratio, 1.69). The yield point approached the ultimate load to failure more closely in the knotless model than in the knotted construct (P = .00094). There was no difference in stiffness, ultimate failure load, or total energy to failure between the knotless and knotted techniques. In rotator cuff repair with a double-row SutureBridge configuration, self-reinforcement is seen in repairs with and without medial-row knots. Self-reinforcement is greater with the knotless technique. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Correlation between the knee adduction torque and medial contact force for a variety of gait patterns.

PubMed

Zhao, Dong; Banks, Scott A; Mitchell, Kim H; D'Lima, Darryl D; Colwell, Clifford W; Fregly, Benjamin J

2007-06-01

The external knee adduction torque has been proposed as a surrogate measure for medial compartment load during gait. However, a direct link between these two quantities has not been demonstrated using in vivo measurement of medial compartment load. This study uses in vivo data collected from a single subject with an instrumented knee implant to evaluate this link. The subject performed five different overground gait motions (normal, fast, slow, wide, and toe-out) with simultaneous collection of instrumented implant, video motion, and ground reaction data. For each trial, the knee adduction torque was measured externally while the total axial force applied to the tibial insert was measured internally. Based on data collected from the same subject performing treadmill gait under fluoroscopic motion analysis, a regression equation was developed to calculate medial contact force from the implant load cell measurements. Correlation analyses were performed for the stance phase and entire gait cycle to quantify the relationship between the knee adduction torque and both the medial contact force and the medial to total contact force ratio. When the entire gait cycle was analyzed, R(2) for medial contact force was 0.77 when all gait trials were analyzed together and between 0.69 and 0.93 when each gait trial was analyzed separately (p < 0.001 in all cases). For medial to total force ratio, R(2) was 0.69 for all trials together and between 0.54 and 0.90 for each trial separately (p < 0.001 in all cases). When only the stance phase was analyzed, R(2) values were slightly lower. These results support the hypothesis that the knee adduction torque is highly correlated with medial compartment contact force and medial to total force ratio during gait. (c) 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Magnetic resonance imaging evidence of meniscal extrusion in medial meniscus posterior root tear.

PubMed

Choi, Chul-Jun; Choi, Yun-Jin; Lee, Jae-Jeong; Choi, Chong-Hyuk

2010-12-01

The purpose of this study was to evaluate the relation between meniscal extrusion on magnetic resonance imaging (MRI) and tearing of the posterior root of the medial meniscus, as well as to understand the relation between meniscal extrusion and chondral lesions. From January 2007 to December 2008, 387 consecutive cases of medial meniscal tears were treated arthroscopically. Of these cases, 248 (64.1%) with MRI were reviewed. Arthroscopic findings were reviewed for the type of tear and medial compartment cartilage lesion. Root tear was defined as a radial tear in the posterior horn of the medial meniscus near the tibial spine (i.e., within 5 mm of the root attachment). An MRI scan of the knee was used to evaluate the presence and extent of meniscal extrusion. Meniscal extrusion of 3 mm or greater was considered pathologic. Arthroscopic findings were compared with respect to the extent of meniscal extrusion. There were 98 male patients and 150 female patients. The mean age was 53.5 years (range, 15 to 81 years). The results showed 127 cases (51.2%) in which the medial meniscus had meniscal extrusion of 3 mm or greater. Posterior root tears were found in 66 (26.6%) of the 248 knees. The mean meniscal extrusion in patients with root tear was 3.8 ± 1.4 mm, whereas the mean extrusion of those who had no root tear was 2.7 ± 1.3 mm. We found an association between pathologic meniscal extrusion and root tear (P < .001). Meniscal extrusion showed a low positive predictive value (39%) and specificity (58%) with regard to the meniscal root tear. Meniscal extrusion was also significantly correlated with severity of chondral lesions (P < .001). Considerable extrusion (≥3 mm) can be associated with tearing of the medial meniscus root and chondral lesion of the medial femoral condyle. Level IV, therapeutic case series. Copyright © 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

[Diagnostic value of MRI for posterior root tear of medial and lateral meniscus].

PubMed

Qian, Yue-Nan; Liu, Fang; Dong, Yi-Long; Cai, Chun-Yuan

2018-03-25

To explore diagnostic value of MRI on posterior root tear of medial and lateral meniscus. From January 2012 to January 2016, clinical data of 43 patients with meniscal posterior root tear confirmed by arthroscopy were retrospective analyzed, including 25 males and 18 females, aged from 27 to 69 years old with an average age of(42.5±8.3)years old;27 cases on the right side and 16 cases on the left side. MRI examinations of 43 patients with tear of posterior meniscus root confirmed by knee arthroscopies were retrospectively reviewed. MRI images were double-blinded, independently, retrospectively scored by two imaging physicians. Sensitivity, specificity and accuracy of MRI diagnosis of lateral and medial meniscus posterior root tear were calculated, and knee ligament injury and meniscal dislocation were calculated. Forty-three of 143 patients were diagnosed with meniscus posterior root tears by arthroscopy, including 19 patients with lateral tears and 24 patients with medial tears. The sensitivity, specificity and accuracy in diagnosis of posterior medial meniscus root tears for doctor A were 91.67%, 86.6% and 83.9% respectively, and for doctor B were 87.5%, 87.4% and 87.4%, 19 patients with medial meniscal protrusion and 2 patients with anterior cruciate ligament tear. The sensitivity, specificity and accuracy in diagnosis of posterior lateral meniscus root tears for doctor A were 73.7%, 79.9% and 79% respectively, and for doctor B were 78.9%, 82.3% and 82.5%, 4 patients with lateral meniscus herniation and 16 patients with cruciate ligament tear. Kappa statistics for posterior medial meniscus root tears and posterior lateral meniscus root tears were 0.84 and 0.72. MRI could effectively demonstrate imaging features of medial and lateral meniscal root tear and its accompanying signs. It could provide the basis for preoperative diagnosis of clinicians, and be worthy to be popularized. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

Characteristics of radial tears in the posterior horn of the medial meniscus compared to horizontal tears.

PubMed

Choi, Chul-Jun; Choi, Yun-Jin; Song, In-Bum; Choi, Chong-Hyuk

2011-06-01

The clinical and radiologic features of radial tears of the medial meniscus posterior horn were compared with those of horizontal tears. From January 2007 to December 2008, 387 consecutive cases of medial meniscal tears were treated arthroscopically. Among these, 91 were radial tears in the medial meniscus posterior horn, and 95 were horizontal tears in the posterior segment of the medial meniscus. The patients' data (age, gender, duration of symptom, body mass index, and injury history), radiographic findings (Kellgren and Lawrence score, posterior tibial slope, and femorotibial angle), and chondral lesions were recorded. The patient factors of age, gender, and body mass index were related to radial tears of the medial meniscus posterior horn. Radial tears were significantly correlated with Kellgren and Lawrence score, varus alignment, posterior tibial slope, and severity of the chondral lesion. Radial tears of the medial meniscus posterior horn are a unique clinical entity that are associated with older age, females and obesity, and are strongly associated with an increased incidence and severity of cartilage degeneration compared to horizontal tears.

A clinical sign to detect root avulsions of the posterior horn of the medial meniscus.

PubMed

Seil, Romain; Dück, Klaus; Pape, Dietrich

2011-12-01

The goal of the present report was to describe a new clinical sign to make a clinical diagnosis of meniscal extrusion related to medial meniscal root avulsion. Description of an easy clinical sign to detect extrusion of the medial meniscus at the anteromedial joint line. A varus stress test was applied in full extension before and after transosseous repair of an isolated traumatic avulsion of the posterior root of the medial meniscus in a 21-year-old patient. The clinical sign was verified by sectioning of the meniscotibial ligament during knee arthroplasty surgery in 3 patients. With a deficient posterior root, the clinical sign was positive, showing anteromedial extrusion under varus stress. After repair and at clinical follow-up, extrusion was normalized. Making the clinical diagnosis of medial meniscus extrusion after knee injury by applying a simple varus stress test to the knee and palpating the anteromedial meniscal extrusion might help physicians to suspect a medial meniscus root tear in the early stages after the injury as well as to evaluate its reduction after repair. A varus stress test in full extension should be performed systematically in patients where a root tear of the medial meniscus is suspected as well as after surgery to evaluate the success of the repair.

A Novel Repair Method for Radial Tears of the Medial Meniscus: Biomechanical Comparison of Transtibial 2-Tunnel and Double Horizontal Mattress Suture Techniques Under Cyclic Loading.

PubMed

Bhatia, Sanjeev; Civitarese, David M; Turnbull, Travis Lee; LaPrade, Christopher M; Nitri, Marco; Wijdicks, Coen A; LaPrade, Robert F

2016-03-01

Complete radial tears of the medial meniscus have been reported to be functionally similar to a total meniscectomy. At present, there is no consensus on an ideal technique for repair of radial midbody tears of the medial meniscus. Prior attempts at repair with double horizontal mattress suture techniques have led to a reportedly high rate of incomplete healing or healing in a nonanatomic (gapped) position, which compromises the ability of the meniscus to withstand hoop stresses. A newly proposed 2-tunnel radial meniscal repair method will result in decreased gapping and increased ultimate failure loads compared with the double horizontal mattress suture repair technique under cyclic loading. Controlled laboratory study. Ten matched pairs of male human cadaveric knees (average age, 58.6 years; range, 48-66 years) were used. A complete radial medial meniscal tear was made at the junction of the posterior one-third and middle third of the meniscus. One knee underwent a horizontal mattress inside-out repair, while the contralateral knee underwent a radial meniscal repair entailing the same technique with a concurrent novel 2-tunnel repair. Specimens were potted and mounted on a universal testing machine. Each specimen was cyclically loaded 1000 times with loads between 5 and 20 N before experiencing a load to failure. Gap distances at the tear site and failure load were measured. The 2-tunnel repairs exhibited a significantly stronger ultimate failure load (median, 196 N; range, 163-212 N) than did the double horizontal mattress suture repairs (median, 106 N; range, 63-229 N) (P = .004). In addition, the 2-tunnel repairs demonstrated decreased gapping at all testing states (P < .05) with a final measured gapping of 1.7 mm and 4.1 mm after 1000 cycles for the 2-tunnel and double horizontal mattress suture repairs, respectively. The 2-tunnel repairs displayed significantly less gapping distance after cyclic loading and had significantly stronger ultimate failure loads

TopMaker: A Technique for Automatic Multi-Block Topology Generation Using the Medial Axis

NASA Technical Reports Server (NTRS)

Heidmann, James D. (Technical Monitor); Rigby, David L.

2004-01-01

A two-dimensional multi-block topology generation technique has been developed. Very general configurations are addressable by the technique. A configuration is defined by a collection of non-intersecting closed curves, which will be referred to as loops. More than a single loop implies that holes exist in the domain, which poses no problem. This technique requires only the medial vertices and the touch points that define each vertex. From the information about the medial vertices, the connectivity between medial vertices is generated. The physical shape of the medial edge is not required. By applying a few simple rules to each medial edge, the multiblock topology is generated with no user intervention required. The resulting topologies contain only the level of complexity dictated by the configurations. Grid lines remain attached to the boundary except at sharp concave turns where a change in index family is introduced as would be desired. Keeping grid lines attached to the boundary is especially important in the area of computational fluid dynamics where highly clustered grids are used near no-slip boundaries. This technique is simple and robust and can easily be incorporated into the overall grid generation process.

Age-Group Differences in Medial Cortex Activity Associated with Thinking About Self-Relevant Agendas

PubMed Central

Mitchell, Karen J.; Raye, Carol L.; Ebner, Natalie C.; Tubridy, Shannon M.; Frankel, Hillary; Johnson, Marcia K.

2009-01-01

This functional magnetic resonance imaging (fMRI) study compared young and older adults’ brain activity as they thought about motivationally self-relevant agendas (hopes and aspirations, duties and obligations) and concrete control items (e.g., shape of USA). Young adults’ activity replicated a double dissociation (Johnson et al., 2006): an area of medial frontal gyrus/anterior cingulate cortex was most active during hopes and aspirations trials and an area of medial posterior cortex, primarily posterior cingulate, was most active during duties and obligations trials. Compared to young adults, older adults showed attenuated responses in medial cortex, especially in medial prefrontal cortex, with both less activity during self-relevant trials and less deactivation during control trials. The fMRI data, together with post-scan reports and the behavioral literature on age-group differences in motivational orientation, suggest that the differences in medial cortex seen in this study reflect young and older adults’ focus on different information during motivationally self-relevant thought. Differences also may be related to an age-associated deficit in controlled cognitive processes that are engaged by complex self-reflection and mediated by prefrontal cortex. PMID:19485660

How tibiofemoral alignment and contact locations affect predictions of medial and lateral tibiofemoral contact forces.

PubMed

Lerner, Zachary F; DeMers, Matthew S; Delp, Scott L; Browning, Raymond C

2015-02-26

Understanding degeneration of biological and prosthetic knee joints requires knowledge of the in-vivo loading environment during activities of daily living. Musculoskeletal models can estimate medial/lateral tibiofemoral compartment contact forces, yet anthropometric differences between individuals make accurate predictions challenging. We developed a full-body OpenSim musculoskeletal model with a knee joint that incorporates subject-specific tibiofemoral alignment (i.e. knee varus-valgus) and geometry (i.e. contact locations). We tested the accuracy of our model and determined the importance of these subject-specific parameters by comparing estimated to measured medial and lateral contact forces during walking in an individual with an instrumented knee replacement and post-operative genu valgum (6°). The errors in the predictions of the first peak medial and lateral contact force were 12.4% and 11.9%, respectively, for a model with subject-specific tibiofemoral alignment and contact locations determined through radiographic analysis, vs. 63.1% and 42.0%, respectively, for a model with generic parameters. We found that each degree of tibiofemoral alignment deviation altered the first peak medial compartment contact force by 51N (r(2)=0.99), while each millimeter of medial-lateral translation of the compartment contact point locations altered the first peak medial compartment contact force by 41N (r(2)=0.99). The model, available at www.simtk.org/home/med-lat-knee/, enables the specification of subject-specific joint alignment and compartment contact locations to more accurately estimate medial and lateral tibiofemoral contact forces in individuals with non-neutral alignment. Copyright © 2015 Elsevier Ltd. All rights reserved.

How Tibiofemoral Alignment and Contact Locations Affect Predictions of Medial and Lateral Tibiofemoral Contact Forces

PubMed Central

Lerner, Zachary F.; DeMers, Matthew S.; Delp, Scott L.; Browning, Raymond C.

2015-01-01

Understanding degeneration of biological and prosthetic knee joints requires knowledge of the in-vivo loading environment during activities of daily living. Musculoskeletal models can estimate medial/lateral tibiofemoral compartment contact forces, yet anthropometric differences between individuals make accurate predictions challenging. We developed a full-body OpenSim musculoskeletal model with a knee joint that incorporates subject-specific tibiofemoral alignment (i.e. knee varus-valgus) and geometry (i.e. contact locations). We tested the accuracy of our model and determined the importance of these subject-specific parameters by comparing estimated to measured medial and lateral contact forces during walking in an individual with an instrumented knee replacement and post-operative genu valgum (6°). The errors in the predictions of the first peak medial and lateral contact force were 12.4% and 11.9%, respectively, for a model with subject-specific tibiofemoral alignment and contact locations determined via radiographic analysis, vs. 63.1% and 42.0%, respectively, for a model with generic parameters. We found that each degree of tibiofemoral alignment deviation altered the first peak medial compartment contact force by 51N (r2=0.99), while each millimeter of medial-lateral translation of the compartment contact point locations altered the first peak medial compartment contact force by 41N (r2=0.99). The model, available at www.simtk.org/home/med-lat-knee/, enables the specification of subject-specific joint alignment and compartment contact locations to more accurately estimate medial and lateral tibiofemoral contact forces in individuals with non-neutral alignment. PMID:25595425

Retrograde amnesia in patients with hippocampal, medial temporal, temporal lobe, or frontal pathology.

PubMed

Bright, Peter; Buckman, Joseph; Fradera, Alex; Yoshimasu, Haruo; Colchester, Alan C F; Kopelman, Michael D

2006-01-01

There is considerable controversy concerning the theoretical basis of retrograde amnesia (R.A.). In the present paper, we compare medial temporal, medial plus lateral temporal, and frontal lesion patients on a new autobiographical memory task and measures of the more semantic aspects of memory (famous faces and news events). Only those patients with damage extending beyond the medial temporal cortex into the lateral temporal regions showed severe impairment on free recall remote memory tasks, and this held for both the autobiographical and the more semantic memory tests. However, on t-test analysis, the medial temporal group was impaired in retrieving recent autobiographical memories. Within the medial temporal group, those patients who had combined hippocampal and parahippocampal atrophy (H+) on quantified MRI performed somewhat worse on the semantic tasks than those with atrophy confined to the hippocampi (H-), but scores were very similar on autobiographical episodic recall. Correlational analyses with regional MRI volumes showed that lateral temporal volume was correlated significantly with performance on all three retrograde amnesia tests. The findings are discussed in terms of consolidation, reconsolidation, and multiple trace theory: We suggest that a widely distributed network of regions underlies the retrieval of past memories, and that the extent of lateral temporal damage appears to be critical to the emergence of a severe remote memory impairment.

Endoscopic modified medial maxillectomy for odontogenic cysts and tumours.

PubMed

Nakayama, Tsugihama; Otori, Nobuyoshi; Asaka, Daiya; Okushi, Tetsushi; Haruna, Shin-ichi

2014-12-01

Odontogenic maxillary cysts and tumours originate from the tooth root and have traditionally been treated through an intraoral approach. Here, we report the efficacy and utility of endoscopic modified medial maxillectomy (EMMM) for the treatment of odontogenic maxillary cysts and a tumour. We undertook EMMM under general anaesthesia in six patients: four had radicular cysts, one had a dentigerous cyst, and one had a keratocystic odontogenic tumour. The cysts and tumours were completely excised and the inferior turbinate and nasolacrimal duct were preserved in all patients. There were no peri- or postoperative complications, and no incidences of recurrence. Endoscopic modified medial maxillectomy appears to be an effective and safe technique for treating odontogenic cysts and tumours.

Neural mechanisms of mother-infant bonding and pair bonding: Similarities, differences, and broader implications

PubMed Central

Numan, Michael; Young, Larry J.

2015-01-01

Mother-infant bonding is a characteristic of virtually all mammals. The maternal neural system may have provided the scaffold upon which other types of social bonds in mammals have been built. For example, most mammals exhibit a polygamous mating system, but monogamy and pair bonding between mating partners occurs in ∼5% of mammalian species. In mammals, it is plausible that the neural mechanisms that promote mother-infant bonding have been modified by natural selection to establish the capacity to develop a selective bond with a mate during the evolution of monogamous mating strategies. Here we compare the details of the neural mechanisms that promote mother-infant bonding in rats and other mammals with those that underpin pair bond formation in the monogamous prairie vole. Although details remain to be resolved, remarkable similarities and a few differences between the mechanisms underlying these two types of bond formation are revealed. For example, amygdala and nucleus accumbens-ventral pallidum (NA-VP) circuits are involved in both types of bond formation, and dopamine and oxytocin action within NA appears to promote the synaptic plasticity that allows either infant or mating partner stimuli to persistently activate NA-VP attraction circuits, leading to an enduring social attraction and bonding. Further, although the medial preoptic area is essential for maternal behavior, its role in pair bonding remains to be determined. Our review concludes by examining the broader implications of this comparative analysis, and evidence is provided that the maternal care system may have also provided the basic neural foundation for other types of strong social relationships, beyond pair bonding, in mammals, including humans. PMID:26062432

Role of Modified Endoscopic Medial Maxillectomy in Persistent Chronic Maxillary Sinusitis

PubMed Central

Thulasidas, Ponnaiah; Vaidyanathan, Venkatraman

2014-01-01

Introduction Functional endoscopic sinus surgery has a long-term high rate of success for symptomatic improvement in patients with medically refractory chronic rhinosinusitis. As the popularity of the technique continues to grow, however, so does the population of patients with postsurgical persistent sinus disease, especially in those with a large window for ventilation and drainage. In addition, chronic infections of the sinuses especially fungal sinusitis have a higher incidence of recurrence even though a wide maxillary ostium had been performed earlier. This subset of patients often represents a challenge to the otorhinolaryngologist. Objectives To identify the patients with chronic recalcitrant maxillary sinusitis and devise treatment protocols for this subset of patients. Methods A retrospective review was done of all patients with persistent maxillary sinus disease who had undergone modified endoscopic medial maxillectomy between 2009 and 2012. We studied patient demographics, previous surgical history, and follow-up details and categorized the types of endoscopic medial maxillectomies performed in different disease situations. Results We performed modified endoscopic medial maxillectomies in 37 maxillary sinuses of 24 patients. The average age was 43.83 years. Average follow-up was 14.58 months. All patients had good disease control in postoperative visits with no clinical evidence of recurrences. Conclusion Modified endoscopic medial maxillectomy appears to be an effective surgery for treatment of chronic, recalcitrant maxillary sinusitis. PMID:25992084

Detection of defects in formed sheet metal using medial axis transformation

NASA Astrophysics Data System (ADS)

Murmu, Naresh C.; Velgan, Roman

2003-05-01

In the metal forming processes, the sheet metals are often prone to various defects such as thinning, dents, wrinkles etc. In the present manufacturing environments with ever increasing demand of higher quality, detecting the defects of formed sheet metal using an effective and objective inspection system is the foremost norm to remain competitive in market. The defect detection using optical techniques aspire to satisfy its needs to be non-contact and fast. However, the main difficulties to achieve this goal remain essentially on the development of efficient evaluation technique and accurate interpretation of extracted data. The defect like thinning is detected by evaluating the deviations of the thickness in the formed sheet metal against its nominal value. The present evaluation procedure for determination of thickness applied on the measurements data is not without deficiency. To improve this procedure, a new evaluation approach based on medial axis transformation is proposed here. The formed sheet metals are digitized using fringe projection systems in different orientations, and afterwards registered into one coordinate frame. The medial axis transformation (MAT) is applied on the point clouds, generating the point clouds of MAT. This data is further processed and medial surface is determined. The thinning defect is detected by evaluating local wall thickness and other defects like wrinkles are determined using the shape recognition on the medial surface. The applied algorithm is simple, fast and robust.

Biomechanical consequences of a tear of the posterior root of the medial meniscus. Surgical technique.

PubMed

Harner, Christopher D; Mauro, Craig S; Lesniak, Bryson P; Romanowski, James R

2009-10-01

Tears of the posterior root of the medial meniscus are becoming increasingly recognized. They can cause rapidly progressive arthritis, yet their biomechanical effects are not understood. The goal of this study was to determine the effects of posterior root tears of the medial meniscus and their repairs on tibiofemoral joint contact pressure and kinematics. Nine fresh-frozen cadaver knees were used. An axial load of 1000 N was applied with a custom testing jig at each of four knee-flexion angles: 0 degrees , 30 degrees , 60 degrees , and 90 degrees . The knees were otherwise unconstrained. Four conditions were tested: (1) intact, (2) a posterior root tear of the medial meniscus, (3) a repaired posterior root tear, and (4) a total medial meniscectomy. Fuji pressure-sensitive film was used to record the contact pressure and area for each testing condition. Kinematic data were obtained by using a robotic arm to record the position of the knees for each loading condition. Three-dimensional knee kinematics were analyzed with custom programs with use of previously described transformations. The measured variables were axial rotation, varus angulation, lateral translation, and anterior translation. In the medial compartment, a posterior root tear of the medial meniscus caused a 25% increase in peak contact pressure compared with that found in the intact condition (p < 0.001). Repair restored the peak contact pressure to normal. No difference was detected between the peak contact pressure after the total medial meniscectomy and that associated with the root tear. The peak contact pressure in the lateral compartment after the total medial meniscectomy was up to 13% greater than that for all other conditions (p = 0.026). Significant increases in external rotation and lateral tibial translation, compared with the values in the intact knee, were observed in association with the posterior root tear (2.98 degrees and 0.84 mm, respectively) and the meniscectomy (4.45 degrees and 0

Person-specific theory of mind in medial pFC.

PubMed

Welborn, B Locke; Lieberman, Matthew D

2015-01-01

Although research on theory of mind has strongly implicated the dorsomedial pFC (incuding medial BA 8 and BA 9), the unique contributions of medial pFC (MPFC; corresponding to medial BA 10) to mentalizing remain uncertain. The extant literature has considered the possibility that these regions may be specialized for self-related cognition or for reasoning about close others, but evidence for both accounts has been inconclusive. We propose a novel theoretical framework: MPFC selectively implements "person-specific theories of mind" (ToMp) representing the unique, idiosyncratic traits or attributes of well-known individuals. To test this hypothesis, we used fMRI to assess MPFC responses in Democratic and Republican participants as they evaluated more or less subjectively well-known political figures. Consistent with the ToMp account, MPFC showed greater activity to subjectively well-known targets, irrespective of participants' reported feelings of closeness or similarity. MPFC also demonstrated greater activity on trials in which targets (whether politicians or oneself) were judged to be relatively idiosyncratic, making a generic theory of mind inapplicable. These results suggest that MPFC may supplement the generic theory of mind process, with which dorsomedial pFC has been associated, by contributing mentalizing capacities tuned to individuated representations of specific well-known others.

Arthroscopic Medial Meniscus Posterior Root Reconstruction Using Auto-Gracilis Tendon.

PubMed

Lee, Dhong Won; Haque, Russel; Chung, Kyu Sung; Kim, Jin Goo

2017-08-01

There have been several techniques to repair the medial meniscus posterior root tears (MMPRTs) with the goal of restoring the anatomic and firm fixation of the meniscal root to bone. Many anatomic studies about the menisci also have been developed, so a better understanding of the anatomy could help surgeons perform correct fixation of the MMPRTs. The meniscal roots have ligament-like structures that firmly attach the menisci to the tibial plateau, and this structural concept is important to restore normal biomechanics after anatomic root repair. We present arthroscopic transtibial medial meniscus posterior root reconstruction using auto-gracilis tendon.

Effect of Posterior Horn Medial Meniscus Root Tear on In Vivo Knee Kinematics.

PubMed

Marsh, Chelsea A; Martin, Daniel E; Harner, Christopher D; Tashman, Scott

2014-07-01

Medial meniscus root tear (MMRT) is a recently recognized yet frequently missed meniscal tear pattern that biomechanically creates an environment approaching meniscal deficiency. The purpose of this study was to assess the effect of MMRT on tibiofemoral kinematics and arthrokinematics during daily activities by comparing the injured knees of subjects with isolated MMRT to their uninjured contralateral knees. The hypothesis was that the injured knee will demonstrate significantly more lateral tibial translation and adduction than the uninjured knee, and that the medial compartment will exhibit significantly different arthrokinematics than the lateral compartment in the affected limb. Cross-sectional study; Level of evidence, 3. Seven subjects with isolated MMRT were recruited and volumetric, density-based 3-dimensional models of their distal femurs and proximal tibia were created from computed tomography scans. High-speed, biplane radiographs were obtained of both their affected and unaffected knees. Moving 3-dimensional models of tibiofemoral kinematics were calculated using model-based tracking to assess overall kinematic variables and specific measures of tibiofemoral joint contact. The affected knees of the subjects were then compared to their unaffected contralateral knees. Affected knees demonstrated significantly more lateral tibial translation than the uninjured contralateral limb in all dynamic activities. Additionally, the medial compartment displayed greater amounts of mobility than the lateral compartment in the injured limbs. This study suggests that MMRT causes significant changes in in vivo knee kinematics and arthrokinematics and that the magnitude of these changes is influenced by dynamic task difficulty. Medial meniscus root tears lead to significant changes in joint arthrokinematics, with increased lateral tibial translation and greater medial compartment excursion. With complete root tears, essentially 100% of circumferential fibers are lost

Root avulsion of the posterior horn of the medial meniscus in skeletally immature patients.

PubMed

Sonnery-Cottet, Bertrand; Mortati, Rafael; Archbold, Pooler; Gadea, François; Clechet, Julien; Thaunat, Mathieu

2014-12-01

Meniscal root avulsion has been predominantly reported in an adult population but little is known about this meniscal lesion in children and adolescents. The of this article is to describe the clinical symptoms and a new MRI sign of a medial meniscus posterior root avulsion in skeletally immature patients, and to report the arthroscopic procedure for its reinsertion in the presence of open physes. We report two skeletally immature patients who had a medial meniscus posterior root avulsion [MMPRA]. Diagnosis of a MMPRA was suspected on MRI by intense T2 hypersignal located at the postero-medial part of the tibial plateau reflecting trabecular bone oedema ("Bone bruise") at the level of the medial meniscal posterior root attachment. Arthroscopic reduction and fixation of the posterior root of the medial meniscus with transosseous sutures was performed. The patients returned to sport at the end of 6 months without residual symptoms. At one year, the radiographs showed no modification of the physis. Healing of the medial meniscal posterior root was noted on MRI. In a skeletally immature patient it is important that this rare meniscal lesion is diagnosed early and adequately treated. We emphasize the importance of the indirect MRI signs that can lead a clinician to suspect the diagnosis of MMPRA. The aim of the surgery was to restore the anatomical footprint of the meniscal root and to re-establish its function thus preventing future chondral damage without damage to the tibial physeal growth plate. Level IV. Copyright © 2014 Elsevier B.V. All rights reserved.

Tibial avulsion fracture of the posterior root of the medial meniscus in children.

PubMed

Iversen, Jonas Vestergård; Krogsgaard, Michael Rindom

2014-01-01

Few reports have described avulsion fractures of the posterior root of the medial meniscus in skeletally immature patients. This lesion should not be overlooked as it damages the load absorptive (distributive) function of the meniscus, increasing the risk of cartilage degeneration. Two cases of displaced avulsion fractures of the posterior root of the medial meniscus in children are presented along with a concise report of the literature regarding avulsion fractures of the posterior root of the medial meniscus. Both avulsions were reattached arthroscopically by trans-tibial pull-out sutures with a good clinical result at 2-years follow-up, and in one case, the avulsion was found at re-arthroscopy after 6 weeks to have healed.

Reversible Information Flow across the Medial Temporal Lobe: The Hippocampus Links Cortical Modules during Memory Retrieval

PubMed Central

Cooper, Elisa; Henson, Richard N.

2013-01-01

A simple cue can be sufficient to elicit vivid recollection of a past episode. Theoretical models suggest that upon perceiving such a cue, disparate episodic elements held in neocortex are retrieved through hippocampal pattern completion. We tested this fundamental assumption by applying functional magnetic resonance imaging (fMRI) while objects or scenes were used to cue participants' recall of previously paired scenes or objects, respectively. We first demonstrate functional segregation within the medial temporal lobe (MTL), showing domain specificity in perirhinal and parahippocampal cortices (for object-processing vs scene-processing, respectively), but domain generality in the hippocampus (retrieval of both stimulus types). Critically, using fMRI latency analysis and dynamic causal modeling, we go on to demonstrate functional integration between these MTL regions during successful memory retrieval, with reversible signal flow from the cue region to the target region via the hippocampus. This supports the claim that the human hippocampus provides the vital associative link that integrates information held in different parts of cortex. PMID:23986252

Multi-parameter analysis of titanium vocal fold medializing implant in an excised larynx model

PubMed Central

Witt, Rachel E.; Hoffman, Matthew R.; Friedrich, Gerhard; Rieves, Adam L.; Schoepke, Benjamin J.; Jiang, Jack J.

2010-01-01

Objective Evaluate the efficacy of the titanium vocal fold medializing implant (TVFMI) for the treatment of unilateral vocal fold paralysis (UVFP) based on acoustic, aerodynamic, and mucosal wave measurements in an excised larynx setup. Methods Measurements were recorded on eight excised canine larynges with simulated UVFP before and after medialization with the TVFMI. Results Phonation threshold flow (PTF) and phonation threshold power (PTW) decreased significantly after medialization (p<0.001; p=0.008). Phonation threshold pressure (PTP) also decreased, but this difference was not significant (p=0.081). Percent jitter and percent shimmer decreased significantly after medialization (p=0.005; p=0.034). Signal to noise ratio (SNR) increased significantly (p=0.05). Differences in mucosal wave characteristics were discernable, but not significant. Phase difference between the normal and paralyzed vocal fold and amplitude of the paralyzed vocal fold decreased (p=0.15; p=0.78). Glottal gap decreased significantly (p=0.004). Conclusions The TVFMI was effective in achieving vocal fold medialization, improving vocal aerodynamic and acoustic characteristics of phonation significantly and mucosal wave characteristics discernibly. This study provides objective, quantitative support for the use of the TVFMI in improving vocal function in patients with unilateral vocal fold paralysis. PMID:20336924

Biomechanical effects of a 2 suture-pass medial inter-implant mattress on transosseous-equivalent rotator cuff repair and considerations for a "technical efficiency ratio".

PubMed

Park, Maxwell C; Peterson, Alexander; Patton, John; McGarry, Michelle H; Park, Chong J; Lee, Thay Q

2014-03-01

Rotator cuff repair involving fewer tendon suture passes without compromising biomechanical performance would represent a technical advancement. An inter-implant "medial pulley-mattress" transosseous-equivalent (MP-TOE) repair requiring fewer tendon suture-passes was hypothesized to provide equivalent biomechanical characteristics compared to the control. In 6 human cadaveric shoulders, a transosseous-equivalent (TOE) repair (control) was performed utilizing 2 separate medial mattresses resulting in 4 tendon-bridging sutures. In 6 matched-pairs, 2 single-loaded anchors were used to create a medial inter-implant mattress construct (all sutures shuttled in 1 tendon pass per anchor)-after knot-tying, the same tendon-bridging pattern as the control was created. A materials testing machine cyclically loaded each repair from 10-180 N for 30 cycles; each repair subsequently underwent failure testing. Gap and strain were measured with a video digitizing system. A "technical efficiency ratio" (TER) was defined as: (#knots + #suture passes + #suture limbs)/#fixation points. Cyclic and failure testing demonstrated no significant differences between constructs. Gap formation at cycle 30 was 5.3 ± 0.8 mm (TOE) and 5.0 ± 0.3 mm (MP-TOE) (P = .62). Cycle 30 anterior strain values were -16.0 ± 7.3% (TOE) and -15.8 ± 6.6% (MP-TOE) (P = .99). Yield loads were 208.7 ± 2.7 N (TOE) and 204.0 ± 1.3 N (MP-TOE) (P = .17). Mode of failure demonstrated less tendon cut-out with the MP-TOE repair. The MP-TOE repair has a TER of 2.0 vs 2.5 for the control. The MP-TOE repair requiring fewer tendon suture passes, yet creating an additional inter-implant mattress configuration, is biomechanically equivalent to the original TOE technique, and may limit failure with improved medial load-sharing capacity. A TER may help quantify technical ease and help standardize comparisons between repair techniques. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights

Electrophysiological analysis of pathways connecting the medial preoptic area with the mesencephalic central grey matter in rats.

PubMed

MacLeod, N K; Mayer, M L

1980-01-01

.7 msec; n = 43). A period of reduced excitability lasting 40--100 msec followed antidromic invasion from either site. 6. Antidromic responses to paired mediobasal hypothalamic or periaqueductal grey matter stimuli at 5 msec intervals revealed an increased latency of invasion of the second response, due to the partial refractory period of the neurone. Five cells showed a decreased latency of invasion at stimulus separations of 10--150 msec, interpreted as evidence of a supranormal period. Changes in conduction velocity during the supranormal period may give rise to a variable latency of invasion of spontaneously active cells. 7. These results provide evidence for direct, reciprocal connexions between the midbrain central grey and the medial preoptic area. These circuits may play a role in controlling neuroendocrine and behavioural aspects of reproductive functions.

Gait retraining and incidence of medial tibial stress syndrome in army recruits.

PubMed

Sharma, Jagannath; Weston, Matthew; Batterham, Alan M; Spears, Iain R

2014-09-01

Gait retraining, comprising biofeedback and/or an exercise intervention, might reduce the risk of musculoskeletal conditions. The purpose was to examine the effect of a gait-retraining program on medial tibial stress syndrome incidence during a 26-wk basic military training regimen. A total of 450 British Army recruits volunteered. On the basis of a baseline plantar pressure variable (mean foot balance during the first 10% of stance), participants classified as at risk of developing medial tibial stress syndrome (n = 166) were randomly allocated to an intervention (n = 83) or control (n = 83) group. The intervention involved supervised gait retraining, including exercises to increase neuromuscular control and flexibility (three sessions per week) and biofeedback enabling internalization of the foot balance variable (one session per week). Both groups continued with the usual military training regimen. Diagnoses of medial tibial stress syndrome over the 26-wk regimen were made by physicians blinded to the group assignment. Data were modeled in a survival analysis using Cox regression, adjusting for baseline foot balance and time to peak heel rotation. The intervention was associated with a substantially reduced instantaneous relative risk of medial tibial stress syndrome versus control, with an adjusted HR of 0.25 (95% confidence interval, 0.05-0.53). The number needed to treat to observe one additional injury-free recruit in intervention versus control at 20 wk was 14 (11 to 23) participants. Baseline foot balance was a nonspecific predictor of injury, with an HR per 2 SD increment of 5.2 (1.6 to 53.6). The intervention was effective in reducing incidence of medial tibial stress syndrome in an at-risk military sample.

TopMaker: Technique Developed for Automatic Multiblock Topology Generation Using the Medial Axis

NASA Technical Reports Server (NTRS)

Rigby, David L.

2004-01-01

The TopMaker technique was developed in an effort to reduce the time required for grid generation in complex numerical studies. Topology generation accounts for much of the man-hours required for structured multiblock grids. With regard to structured multiblock grids, topology refers to how the blocks are arranged and connected. A two-dimensional multiblock topology generation technique has been developed at the NASA Glenn Research Center. Very general configurations can be addressed by the technique. A configuration is defined by a collection of non-intersecting closed curves, which will be referred to as loops. More than a single loop implies that holes exist in the domain, which poses no problem. This technique requires only the medial vertices and the touch points that define each vertex. From the information about the medial vertices, the connectivity between medial vertices is generated. The physical shape of the medial edge is not required. By applying a few simple rules to each medial edge, a multiblock topology can be generated without user intervention. The resulting topologies contain only the level of complexity dictated by the configurations. Grid lines remain attached to the boundary except at sharp concave turns, where a change in index family is introduced as would be desired. Keeping grid lines attached to the boundary is especially important in computational fluid dynamics, where highly clustered grids are used near no-slip boundaries. This technique is simple and robust and can easily be incorporated into the overall grid-generation process.

A new surgical technique for medial collateral ligament balancing: multiple needle puncturing.

PubMed

Bellemans, Johan; Vandenneucker, Hilde; Van Lauwe, Johan; Victor, Jan

2010-10-01

In this article, we present our experience with a new technique for medial soft tissue balancing, where we make multiple punctures in the medial collateral ligament (MCL) using a 19-gauge needle, to progressively stretch the MCL until a correct ligament balance is achieved. Ligament status was evaluated both before and after the procedure using computer navigation and mediolateral stress testing. The procedure was considered successful when 2 to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 34 of 35 cases, a progressive correction of medial tightness was achieved according to the above described criteria. One case was considered overreleased in extension. Needle puncturing is a new, effective, and safe technique for progressive correction of MCL tightness in the varus knee. Copyright © 2010 Elsevier Inc. All rights reserved.

The benefit of therapeutic medial branch blocks after cervical operations.

PubMed

Klessinger, Stephan

2010-01-01

Persistent neck pain is a common problem after surgery of the cervical spine. No therapy recommendation exists for these patients. The objective of this study was to determine if a therapeutic medial branch block is a rational treatment for patients with postoperative neck pain after cervical spine operations. Retrospective practice audit. Review of charts of all patients who underwent cervical spine operations for degenerative reasons during a time period of 3 years. Patients with persistent postsurgical pain were treated with therapeutic medial branch blocks (local anesthetic and steroid). A positive treatment response was defined if at least 80% reduction of pain could be achieved or if the patient was sufficiently satisfied with the relief. All patients with a minimum follow up time of 6 months were included. Of the 312 operations performed, 128 were artificial disc operations, 125 were stand alone cages, and 59 were fusions with cage and plate. Persistent neck pain occurred in 33.3% of the patients. There was no difference between the patients with neck pain and the whole group of patients. More than half of the patients with neck pain--52.9%--were treated successfully with therapeutic medial branch blocks. Since no further treatment was necessary, the initial treatment was considered successful. Nearly a third--32.2%--of the patients were initially treated successfully, but their pain recurred and further diagnostics and treatments were necessary. In this group of patients, significantly more with double level operations were found (P = 0.003). Patients not responding to the medial branch block were 14.9%. This audit is retrospective and observational, and therefore does not represent a high level of evidence. However, to our knowledge, since this information has not been previously reported and no recommendation for the treatment of post-operative zygapophysial joint pain exists, it appears to be the best available research upon which to recommend treatment

Double transosseous pull out suture technique for transection of posterior horn of medial meniscus.

PubMed

Ahn, Jin Hwan; Wang, Joon Ho; Lim, Hong Chul; Bae, Ji Hoon; Park, Joon Soo; Yoo, Jae Chul; Shyam, Ashok Kumar

2009-03-01

Transection injury (complete radial tear, root tear) in the posterior horn of medial meniscus will lead to loss of hoop strain, extrusion of the meniscus and early degenerative changes. The posterior horn of medial meniscus is amenable to repair due to its good blood supply and repair is the procedure of choice for these injuries. In cases of transection of the medial meniscus posterior horn, the meniscus can be repaired by a pull out suture technique using trans-septal portal. The single transosseous pull out suturing technique is a point fixation technique with limited contact area having low and inhomogeneous contact pressure. This article describes a double transosseous pull out suture technique using trans-septal portal for the repair of transection of posterior horn of medial meniscus. Use of double transosseous technique provides more secure fixation, more homogeneous and wider contact pressure area between meniscus and the bone, improving the healing potential of the repair.

Base pairing and base mis-pairing in nucleic acids

NASA Technical Reports Server (NTRS)

Wang, A. H. J.; Rich, A.

1986-01-01

In recent years we have learned that DNA is conformationally active. It can exist in a number of different stable conformations including both right-handed and left-handed forms. Using single crystal X-ray diffraction analysis we are able to discover not only additional conformations of the nucleic acids but also different types of hydrogen bonded base-base interactions. Although Watson-Crick base pairings are the predominant type of interaction in double helical DNA, they are not the only types. Recently, we have been able to examine mismatching of guanine-thymine base pairs in left-handed Z-DNA at atomic resolution (1A). A minimum amount of distortion of the sugar phosphate backbone is found in the G x T pairing in which the bases are held together by two hydrogen bonds in the wobble pairing interaction. Because of the high resolution of the analysis we can visualize water molecules which fill in to accommodate the other hydrogen bonding positions in the bases which are not used in the base-base interactions. Studies on other DNA oligomers have revealed that other types of non-Watson-Crick hydrogen bonding interactions can occur. In the structure of a DNA octamer with the sequence d(GCGTACGC) complexed to an antibiotic triostin A, it was found that the two central AT base pairs are held together by Hoogsteen rather than Watson-Crick base pairs. Similarly, the G x C base pairs at the ends are also Hoogsteen rather than Watson-Crick pairing. Hoogsteen base pairs make a modified helix which is distinct from the Watson-Crick double helix.

Analysis of 3D strain in the human medial meniscus.

PubMed

Kolaczek, S; Hewison, C; Caterine, S; Ragbar, M X; Getgood, A; Gordon, K D

2016-10-01

This study presents a method to evaluate three-dimensional strain in meniscal tissue using medical imaging. Strain is calculated by tracking small teflon markers implanted within the meniscal tissue using computed tomography imaging. The results are presented for strains in the middle and posterior third of the medial menisci of 10 human cadaveric knees, under simulated physiologically relevant loading. In the middle position, an average compressive strain of 3.4% was found in the medial-lateral direction, and average tensile strains of 1.4% and 3.5% were found in the anterior-posterior and superior-inferior directions respectively at 5° of knee flexion with an applied load of 1× body weight. In the posterior position, under the same conditions, average compressive strains of 2.2% and 6.3% were found in the medial-lateral and superior-inferior directions respectively, and an average tensile strain of 3.8% was found in the anterior-posterior direction. No statistically significant difference between strain in the middle or posterior of the meniscus or between the global strains is uncovered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Classification and Surgical Repair of Ramp Lesions of the Medial Meniscus.

PubMed

Thaunat, Mathieu; Fayard, Jean Marie; Guimaraes, Tales M; Jan, Nicolas; Murphy, Colin G; Sonnery-Cottet, Bertrand

2016-08-01

Ramp lesions of the medial meniscus are commonly associated with anterior cruciate ligament ruptures and consist of longitudinal peripheral tears of the posterior horn of the medial meniscus. Given the frequency of partial-thickness tears, they can be difficult to diagnose arthroscopically from the anterior compartment. We describe a classification of the different types of ramp lesions depending on both tear pattern (partial- or full-thickness tear) and associated meniscotibial ligament disruption. An original technique of arthroscopic suture placement through a single posteromedial portal with a 25° curved suture hook device is described.

Acute Medial Plantar Fascia Tear.

PubMed

Pascoe, Stephanie C; Mazzola, Timothy J

2016-06-01

A 32-year-old man who participated in competitive soccer came to physical therapy via direct access for a chief complaint of plantar foot pain. The clinical examination findings and mechanism of injury raised a concern for a plantar fascia tear, so the patient was referred to the physician and magnetic resonance imaging was obtained. The magnetic resonance image confirmed a high-grade, partial-thickness, proximal plantar fascia tear with localized edema at the location of the medial band. J Orthop Sports Phys Ther 2016;46(6):495. doi:10.2519/jospt.2016.0409.

Medial vestibular connections with the hypocretin (orexin) system

NASA Technical Reports Server (NTRS)

Horowitz, Seth S.; Blanchard, Jane; Morin, Lawrence P.

2005-01-01

The mammalian medial vestibular nucleus (MVe) receives input from all vestibular endorgans and provides extensive projections to the central nervous system. Recent studies have demonstrated projections from the MVe to the circadian rhythm system. In addition, there are known projections from the MVe to regions considered to be involved in sleep and arousal. In this study, afferent and efferent subcortical connectivity of the medial vestibular nucleus of the golden hamster (Mesocricetus auratus) was evaluated using cholera toxin subunit-B (retrograde), Phaseolus vulgaris leucoagglutinin (anterograde), and pseudorabies virus (transneuronal retrograde) tract-tracing techniques. The results demonstrate MVe connections with regions mediating visuomotor and postural control, as previously observed in other mammals. The data also identify extensive projections from the MVe to regions mediating arousal and sleep-related functions, most of which receive immunohistochemically identified projections from the lateral hypothalamic hypocretin (orexin) neurons. These include the locus coeruleus, dorsal and pedunculopontine tegmental nuclei, dorsal raphe, and lateral preoptic area. The MVe itself receives a projection from hypocretin cells. CTB tracing demonstrated reciprocal connections between the MVe and most brain areas receiving MVe efferents. Virus tracing confirmed and extended the MVe afferent connections identified with CTB and additionally demonstrated transneuronal connectivity with the suprachiasmatic nucleus and the medial habenular nucleus. These anatomical data indicate that the vestibular system has access to a broad array of neural functions not typically associated with visuomotor, balance, or equilibrium, and that the MVe is likely to receive information from many of the same regions to which it projects.

Medial malleolar fractures: a biomechanical study of fixation techniques.

PubMed

Fowler, T Ty; Pugh, Kevin J; Litsky, Alan S; Taylor, Benjamin C; French, Bruce G

2011-08-08

Fracture fixation of the medial malleolus in rotationally unstable ankle fractures typically results in healing with current fixation methods. However, when failure occurs, pullout of the screws from tension, compression, and rotational forces is predictable. We sought to biomechanically test a relatively new technique of bicortical screw fixation for medial malleoli fractures. Also, the AO group recommends tension-band fixation of small avulsion type fractures of the medial malleolus that are unacceptable for screw fixation. A well-documented complication of this technique is prominent symptomatic implants and secondary surgery for implant removal. Replacing stainless steel 18-gauge wire with FiberWire suture could theoretically decrease symptomatic implants. Therefore, a second goal was to biomechanically compare these 2 tension-band constructs. Using a tibial Sawbones model, 2 bicortical screws were compared with 2 unicortical cancellous screws on a servohydraulic test frame in offset axial, transverse, and tension loading. Second, tension-band fixation using stainless steel wire was compared with FiberWire under tensile loads. Bicortical screw fixation was statistically the stiffest construct under tension loading conditions compared to unicortical screw fixation and tension-band techniques with FiberWire or stainless steel wire. In fact, unicortical screw fixation had only 10% of the stiffness as demonstrated in the bicortical technique. In a direct comparison, tension-band fixation using stainless steel wire was statistically stiffer than the FiberWire construct. Copyright 2011, SLACK Incorporated.

Medial prefrontal cortex circuit function during retrieval and extinction of associative learning under anesthesia.

PubMed

Fenton, G E; Halliday, D M; Mason, R; Stevenson, C W

2014-04-18

Associative learning is encoded under anesthesia and involves the medial prefrontal cortex (mPFC). Neuronal activity in mPFC increases in response to a conditioned stimulus (CS+) previously paired with an unconditioned stimulus (US) but not during presentation of an unpaired stimulus (CS-) in anesthetized animals. Studies in conscious animals have shown dissociable roles for different mPFC subregions in mediating various memory processes, with the prelimbic (PL) and infralimbic (IL) cortex involved in the retrieval and extinction of conditioned responding, respectively. Therefore PL and IL may also play different roles in mediating the retrieval and extinction of discrimination learning under anesthesia. Here we used in vivo electrophysiology to examine unit and local field potential (LFP) activity in PL and IL before and after auditory discrimination learning and during later retrieval and extinction testing in anesthetized rats. Animals received repeated presentations of two distinct sounds, one of which was paired with footshock (US). In separate control experiments animals received footshocks without sounds. After discrimination learning the paired (CS+) and unpaired (CS-) sounds were repeatedly presented alone. We found increased unit firing and LFP power in PL and, to a lesser extent, IL after discrimination learning but not after footshocks alone. After discrimination learning, unit firing and LFP power increased in PL and IL in response to presentation of the first CS+, compared to the first CS-. However, PL and IL activity increased during the last CS- presentation, such that activity during presentation of the last CS+ and CS- did not differ. These results confirm previous findings and extend them by showing that increased PL and IL activity result from encoding of the CS+/US association rather than US presentation. They also suggest that extinction may occur under anesthesia and might be represented at the neural level in PL and IL. Copyright © 2014 The

The effects of anterior arcuate and dorsomedial frontal cortex lesions on visually guided eye movements: 2. Paired and multiple targets.

PubMed

Schiller, P H; Chou, I

2000-01-01

This study examined the effects of anterior arcuate and dorsomedial frontal cortex lesions on the execution of saccadic eye movements made to paired and multiple targets in rhesus monkeys. Identical paired targets were presented with various temporal asynchronies to determine the temporal offset required to yield equal probability choices to either target. In the intact animal equal probability choices were typically obtained when the targets appeared simultaneously. After unilateral anterior arcuate lesions a major shift arose in the temporal offset required to obtain equal probability choices for paired targets that necessitated presenting the target in the hemifield contralateral to the lesion more than 100 ms prior to the target in the ipsilateral hemifield. This deficit was still pronounced 1 year after the lesion. Dorsomedial frontal cortex lesions produced much smaller but significant shifts in target selection that recovered more rapidly. Paired lesions produced deficits similar to those observed with anterior arcuate lesions alone. Major deficits were also observed on a multiple target temporal discrimination task after anterior arcuate but not after dorsomedial frontal cortex lesions. These results suggest that the frontal eye fields that reside in anterior bank of the arcuate sulcus play an important role in temporal processing and in target selection. Dorsomedial frontal cortex, that contains the medial eye fields, plays a much less important role in the execution of these tasks.

The medial frontal cortex contributes to but does not organize rat exploratory behavior.

PubMed

Blankenship, Philip A; Stuebing, Sarah L; Winter, Shawn S; Cheatwood, Joseph L; Benson, James D; Whishaw, Ian Q; Wallace, Douglas G

2016-11-12

Animals use multiple strategies to maintain spatial orientation. Dead reckoning is a form of spatial navigation that depends on self-movement cue processing. During dead reckoning, the generation of self-movement cues from a starting position to an animal's current position allow for the estimation of direction and distance to the position movement originated. A network of brain structures has been implicated in dead reckoning. Recent work has provided evidence that the medial frontal cortex may contribute to dead reckoning in this network of brain structures. The current study investigated the organization of rat exploratory behavior subsequent to medial frontal cortex aspiration lesions under light and dark conditions. Disruptions in exploratory behavior associated with medial frontal lesions were consistent with impaired motor coordination, response inhibition, or egocentric reference frame. These processes are necessary for spatial orientation; however, they are not sufficient for self-movement cue processing. Therefore it is possible that the medial frontal cortex provides processing resources that support dead reckoning in other brain structures but does not of itself compute the kinematic details of dead reckoning. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Malignant lesions are rare in medial third of the clavicle in children: the European Juvenile Medial End of Clavicle Tumour study.

PubMed

Clement, Nicholas David; Nyadu, Yaw; Kelly, Michael; Walmsley, Phillip; Porter, Daniel E

2011-05-01

Condensing osteitis is a condition presenting to all paediatric orthopaedic services, but the prevalence of the condition and optimal management is difficult to determine from the literature. Many case reports in the orthopaedic literature describe biopsy to exclude malignancy as mandatory, whereas expert radiological opinion has suggested that lesions can be classified as typical of sclerosing osteitis on imaging alone. The aim of this study was to calculate an accurate incidence of malignancy at the medial end of the clavicle in children based on data held by national and regional cancer registries in Europe. In addition, this study determined the published success of biopsy in identifying a causative organism. The investigators wrote to 173 European national or regional cancer registries requesting the number of malignant lesions at the medial end of the clavicle in those less than 19 years of age, how long the registry had been in existence and the size of the population served. A literature review was conducted of Medline and Pubmed using the terms, 'condensing osteitis,' 'chronic recurrent multiostotic osteomyelitis,' 'acute osteomyelitis,' 'chronic osteomyelitis clavicle,' 'sclerosing osteitis' and 'sclerosing osteomyelitis' and refined to those regarding the clavicle. The incidence of malignancy at the medial end of the clavicle was found to be extremely low (one case every 275 child-years at risk). In addition, biopsy rarely identified a causative organism with only two of 89 biopsies being positive. We suggest that for a chronic nonmalignant process in which clinical features are typical, serial imaging with follow-up is sufficient although timely biopsy would be recommended when doubt exists.

The prevalence of medial coronoid process disease is high in lame large breed dogs and quantitative radiographic assessments contribute to the diagnosis.

PubMed

Mostafa, Ayman; Nolte, Ingo; Wefstaedt, Patrick

2018-06-05

Medial coronoid process disease is a common leading cause of thoracic limb lameness in dogs. Computed tomography and arthroscopy are superior to radiography to diagnose medial coronoid process disease, however, radiography remains the most available diagnostic imaging modality in veterinary practice. Objectives of this retrospective observational study were to describe the prevalence of medial coronoid process disease in lame large breed dogs and apply a novel method for quantifying the radiographic changes associated with medial coronoid process and subtrochlear-ulnar region in Labrador and Golden Retrievers with confirmed medial coronoid process disease. Purebred Labrador and Golden Retrievers (n = 143, 206 elbows) without and with confirmed medial coronoid process disease were included. The prevalence of medial coronoid process disease in lame large breed dogs was calculated. Mediolateral and craniocaudal radiographs of elbows were analyzed to assess the medial coronoid process length and morphology, and subtrochlear-ulnar width. Mean grayscale value was calculated for radial and subtrochlear-ulnar zones. The prevalence of medial coronoid process disease was 20.8%. Labrador and Golden Retrievers were the most affected purebred dogs (29.6%). Elbows with confirmed medial coronoid process disease had short (P < 0.0001) and deformed (∼95%) medial coronoid process, with associated medial coronoid process osteophytosis (7.5%). Subtrochlear-ulnar sclerosis was evidenced in ∼96% of diseased elbows, with a significant increase (P < 0.0001) in subtrochlear-ulnar width and standardized grayscale value. Radial grayscale value did not differ between groups. Periarticular osteophytosis was identified in 51.4% of elbows with medial coronoid process disease. Medial coronoid process length and morphology, and subtrochlear-ulnar width and standardized grayscale value varied significantly in dogs with confirmed medial coronoid process disease compared to controls

Diagnosis of the "large medial meniscus" of the knee on MR imaging.

PubMed

Samoto, Nobuhiko; Kozuma, Masakazu; Tokuhisa, Toshio; Kobayashi, Kunio

2006-11-01

Although several quantitative magnetic resonance (MR) diagnostic criteria for discoid lateral meniscus (DLM) have been described, there are no criteria by which to estimate the size of the medial meniscus. We define a medial meniscus that exceeds the normal size as a "large medial meniscus" (LMM), and the purpose of this study is to establish the quantitative MR diagnostic criteria for LMM. The MR imaging findings of 96 knees with arthroscopically confirmed intact semilunar lateral meniscus (SLM), 18 knees with intact DLM, 105 knees with intact semilunar medial meniscus (SMM) and 4 knees with torn LMM were analyzed. The following three quantitative parameters were measured: (a) meniscal width (MW): the minimum MW on the coronal slice; (b) ratio of the meniscus to the tibia (RMT): the ratio of minimum MW to maximum tibial width on the coronal slice; (c) continuity of the anterior and posterior horns (CAPH): the number of consecutive 5-mm-thick sagittal slices showing continuity between the anterior horn and the posterior horn of the meniscus on sagittal slices. Using logistic discriminant analysis between intact SLM and DLM groups and using descriptive statistics of intact SLM and SMM groups, the cutoff values used to discriminate LMM from SMM were calculated by MW and RMT. Moreover, the efficacy of these cutoff values and three slices of the cutoff values for CAPH were estimated in the medial meniscus group. "MW> or =11 mm" and "RMT> or =15%" were determined to be effective diagnostic criteria for LMM, while three of four cases in the torn LMM group were true positives and specificity was 99% in both criteria. When "CAPH> or =3 slices" was used as a criterion, three of four torn LMM cases were true positives and specificity was 93%.

Rupture of posterior cruciate ligament leads to radial displacement of the medial meniscus.

PubMed

Zhang, Can; Deng, Zhenhan; Luo, Wei; Xiao, Wenfeng; Hu, Yihe; Liao, Zhan; Li, Kanghua; He, Hongbo

2017-07-11

To explore the association between the rupture of posterior cruciate ligament (PCL) and the radial displacement of medial meniscus under the conditions of different flexion and various axial loads. The radial displacement value of medial meniscus was measured for the specimens of normal adult knee joints, including 12 intact PCLs, 6 ruptures of the anterolateral bundle (ALB), 6 ruptures of the postmedial bundle (PMB), and 12 complete ruptures. The measurement was conducted at 0°, 30°, 60°, and 90° of knee flexion angles under 200 N, 400 N, 600 N, 800 N and 1000 N of axial loads respectively. The displacement values of medial meniscus of the ALB rupture group increased at 0° flexion under 800 N and 1000 N, and at 30°, 60° and 90° flexion under all loads in comparison with the PCL intact group. The displacement values of the PMB rupture group was higher at 0° and 90° flexion under all loads, and at 30° and 60° flexion under 800 N and 1000 N loads. The displacement of the PCL complete rupture group increased at all flexion angles under all loads. Either partial or complete rupture of the PCL can increase in the radial displacement of the medial meniscus, which may explain the degenerative changes that occuring in the medial meniscus due to PCL injury. Therefore, early reestablishment of the PCL is necessarily required in order to maintain stability of the knee joint after PCL injury.

Neural mechanisms of mother-infant bonding and pair bonding: Similarities, differences, and broader implications.

PubMed

Numan, Michael; Young, Larry J

2016-01-01

This article is part of a Special Issue "Parental Care". Mother-infant bonding is a characteristic of virtually all mammals. The maternal neural system may have provided the scaffold upon which other types of social bonds in mammals have been built. For example, most mammals exhibit a polygamous mating system, but monogamy and pair bonding between mating partners occur in ~5% of mammalian species. In mammals, it is plausible that the neural mechanisms that promote mother-infant bonding have been modified by natural selection to establish the capacity to develop a selective bond with a mate during the evolution of monogamous mating strategies. Here we compare the details of the neural mechanisms that promote mother-infant bonding in rats and other mammals with those that underpin pair bond formation in the monogamous prairie vole. Although details remain to be resolved, remarkable similarities and a few differences between the mechanisms underlying these two types of bond formation are revealed. For example, amygdala and nucleus accumbens-ventral pallidum (NA-VP) circuits are involved in both types of bond formation, and dopamine and oxytocin actions within NA appear to promote the synaptic plasticity that allows either infant or mating partner stimuli to persistently activate NA-VP attraction circuits, leading to an enduring social attraction and bonding. Further, although the medial preoptic area is essential for maternal behavior, its role in pair bonding remains to be determined. Our review concludes by examining the broader implications of this comparative analysis, and evidence is provided that the maternal care system may have also provided the basic neural foundation for other types of strong social relationships, beyond pair bonding, in mammals, including humans. Copyright © 2015 Elsevier Inc. All rights reserved.

Making sense: Dopamine activates conscious self‐monitoring through medial prefrontal cortex

PubMed Central

Joensson, Morten; Thomsen, Kristine Rømer; Andersen, Lau M.; Gross, Joachim; Mouridsen, Kim; Sandberg, Kristian; Østergaard, Leif

2015-01-01

Abstract When experiences become meaningful to the self, they are linked to synchronous activity in a paralimbic network of self‐awareness and dopaminergic activity. This network includes medial prefrontal and medial parietal/posterior cingulate cortices, where transcranial magnetic stimulation may transiently impair self‐awareness. Conversely, we hypothesize that dopaminergic stimulation may improve self‐awareness and metacognition (i.e., the ability of the brain to consciously monitor its own cognitive processes). Here, we demonstrate improved noetic (conscious) metacognition by oral administration of 100 mg dopamine in minimal self‐awareness. In a separate experiment with extended self‐awareness dopamine improved the retrieval accuracy of memories of self‐judgment (autonoetic, i.e., explicitly self‐conscious) metacognition. Concomitantly, magnetoencephalography (MEG) showed increased amplitudes of oscillations (power) preferentially in the medial prefrontal cortex. Given that electromagnetic activity in this region is instrumental in self‐awareness, this explains the specific effect of dopamine on explicit self‐awareness and autonoetic metacognition. Hum Brain Mapp 36:1866–1877, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.. PMID:25627861

Injuries of the Medial Clavicle: A Cohort Analysis in a Level-I-Trauma-Center. Concomitant Injuries. Management. Classification.

PubMed

Bakir, Mustafa Sinan; Merschin, David; Unterkofler, Jan; Guembel, Denis; Langenbach, Andreas; Ekkernkamp, Axel; Schulz-Drost, Stefan

2017-01-01

Introduction: Although shoulder girdle injuries are frequent, those of the medial clavicle are widely unexplored. An applied classification is less used just as a standard management. Methods: A retrospective analysis of medial clavicle injuries (MCI) during a 5-year-term in a Level-1-Trauma-Center. We analyzed amongst others concomitant injuries, therapy strategies and the classification following the AO standards. Results: 19 (2.5%) out of 759 clavicula injuries were medial ones (11 A, 6 B and 2 C-Type fractures) thereunder 27,8% were displaced and thus operatively treated Locked plate osteosynthesis was employed in unstable fractures and a reconstruction of the ligaments at the sternoclavicular joint (SCJ) in case of their disruption. 84,2% of the patients sustained relevant concomitant injuries. Numerous midshaft fractures were miscoded as medial fracture, which limited the study population. Conclusions: MCI resulted from high impact mechanisms of injury, often with relevant dislocation and concomitant injuries. Concerning medial injury's complexity, treatment should occur in specialized hospitals. Unstable fractures and injuries of the SCJ ligaments should be considered for operative treatment. Midshaft fractures should be clearly distinguished from the medial ones in ICD-10-coding. Further studies are required also regarding a subtyping of the AO classification for medial clavicle fractures including ligamental injuries. Celsius.

Medial unicondylar knee arthroplasty combined to anterior cruciate ligament reconstruction.

PubMed

Ventura, Alberto; Legnani, Claudio; Terzaghi, Clara; Iori, Stefano; Borgo, Enrico

2017-03-01

The purpose of the present study was to retrospectively evaluate the outcomes of patients who underwent combined medial unicompartmental knee arthroplasty (UKA) and anterior cruciate ligament (ACL) reconstruction. The hypothesis was that this procedure would lead to a high success rate in patients affected by isolated medial unicompartmental osteoarthritis and concomitant ACL deficiency. Fourteen patients with primary ACL lesion and concomitant medial compartment symptomatic osteoarthritis treated from 2006 to 2010 were followed up for an average time of 26.7 months (SD 4.2). Assessment included KOOS score, Oxford Knee score, American Knee Society scores, WOMAC index of osteoarthritis, Tegner activity level and objective examination including instrumented laxity test with KT-1000 arthrometer. Radiological assessment was done with standard simple radiographs in order to get information about any presence of loosening of the components. KOOS score, OKS, WOMAC index and the AKSS improved significantly after surgery (p < 0.001). Regarding AKSS, improvement was noted both in the objective score and in the functional one (p < 0.001). There was no clinical evidence of instability in any of the knees as evaluated with clinical laxity testing. No pathologic radiolucent lines were observed around the components. In one patient signs of osteoarthritis in the lateral compartment were observed 28 months after surgery. UKA combined with ACL reconstruction is a valid therapeutic option for the treatment of combined medial unicompartmental knee osteoarthritis and ACL deficiency in young and active patients and confirms subjective and objective clinical improvement 2 years after surgery. The use of a fixed-bearing prosthesis represents a reliable feature as it allows to overcome problems of improper ligament tensioning during the implantation of the components. IV.

Modified endoscopic medial maxillectomy for zygomatic implant salvage.

PubMed

Schwartz, Joseph S; Tajudeen, Bobby A; Adappa, Nithin D; Palmer, James N

2016-01-01

Odontogenic chronic rhinosinusitis (CRS) is an epidemiologically important disease process due, in part, to the increasingly commonplace use of dental restorative procedures such as zygomatic implantation. Traditional management of this clinical entity typically entails extraction of the infected hardware via an open or endoscopic approach. We describe a novel management strategy of odontogenic CRS following bilateral zygomatic implantation for oral rehabilitation that we surgically salvaged via a modified endoscopic medial maxillectomy. We describe the presentation and management of a case of metachronous development of bilateral CRS subsequent to zygomatic implantation. The patient's postoperative course was characterized by marked endoscopic, radiologic, and symptomatic improvement as measured by the 22-item Sino-Nasal Outcome Test. We describe a novel treatment strategy for the management of odontogenic sinusitis resulting from erroneous zygomatic implant placement. Modified endoscopic medial maxillectomy in this clinical context facilitates mucosal normalization of the affected sinus, while permitting preservation of oral function through salvage of the displaced implant.

Modified endoscopic medial maxillectomy for zygomatic implant salvage

PubMed Central

Tajudeen, Bobby A.; Adappa, Nithin D.; Palmer, James N.

2016-01-01

Objectives: Odontogenic chronic rhinosinusitis (CRS) is an epidemiologically important disease process due, in part, to the increasingly commonplace use of dental restorative procedures such as zygomatic implantation. Traditional management of this clinical entity typically entails extraction of the infected hardware via an open or endoscopic approach. We describe a novel management strategy of odontogenic CRS following bilateral zygomatic implantation for oral rehabilitation that we surgically salvaged via a modified endoscopic medial maxillectomy. Methods: We describe the presentation and management of a case of metachronous development of bilateral CRS subsequent to zygomatic implantation. Results: The patient's postoperative course was characterized by marked endoscopic, radiologic, and symptomatic improvement as measured by the 22-item Sino-Nasal Outcome Test. Conclusion: We describe a novel treatment strategy for the management of odontogenic sinusitis resulting from erroneous zygomatic implant placement. Modified endoscopic medial maxillectomy in this clinical context facilitates mucosal normalization of the affected sinus, while permitting preservation of oral function through salvage of the displaced implant. PMID:28107147

Multiple running speed signals in medial entorhinal cortex

PubMed Central

Hinman, James R.; Brandon, Mark P.; Climer, Jason R.; Chapman, G. William; Hasselmo, Michael E.

2016-01-01

Grid cells in medial entorhinal cortex (MEC) can be modeled using oscillatory interference or attractor dynamic mechanisms that perform path integration, a computation requiring information about running direction and speed. The two classes of computational models often use either an oscillatory frequency or a firing rate that increases as a function of running speed. Yet it is currently not known whether these are two manifestations of the same speed signal or dissociable signals with potentially different anatomical substrates. We examined coding of running speed in MEC and identified these two speed signals to be independent of each other within individual neurons. The medial septum (MS) is strongly linked to locomotor behavior and removal of MS input resulted in strengthening of the firing rate speed signal, while decreasing the strength of the oscillatory speed signal. Thus two speed signals are present in MEC that are differentially affected by disrupted MS input. PMID:27427460

Medial capsular interpositional arthroplasty for severe hallux rigidus.

PubMed

Hahn, Michael Patrick; Gerhardt, Nels; Thordarson, David B

2009-06-01

Multiple surgical options have been described for severe hallux rigidus. One option is capsular interpositional arthroplasty. We report our initial results with a technique using the thicker medial capsule as our interpositional material instead of the dorsal capsule and extensor hallucis brevis (EHB). Twenty-two patients with grade IV hallux rigidus underwent minimal proximal phalanx resection (modified Keller) with preservation of the flexor hallucis brevis (FHB) insertion and medial capsular interpositional arthroplasty. Postoperative AOFAS hallux MTP-IP scores (mean 77.8), and SF-36 scores (mean 68.7 on physical function, 79.5 role limitations) demonstrated clinical improvement compared to historical controls. Alignment and stability were well maintained (mean preoperative HV angle of 11.8 degrees, mean postoperative HV angle of 13.0 degrees). Dorsiflexion/plantarflexion arc of motion showed sustained improvement (mean 38.4 degrees preoperative, mean 62.3 degrees postoperative). These results are comparable to other forms of interpositional arthroplasty and arthrodesis for end stage arthritis of the hallux MTPJ.

Comminuted supracondylar femoral fractures: a biomechanical analysis comparing the stability of medial versus lateral plating in axial loading.

PubMed

Briffa, Nikolai; Karthickeyan, Raju; Jacob, Joshua; Khaleel, Arshad

2016-11-01

The aim of this study was to compare the biomechanical properties of medial and lateral plating of a medially comminuted supracondylar femoral fracture. A supracondylar femoral fracture model comparing two fixation methods was tested cyclically in axial loading. One-centimetre supracondylar gap osteotomies were created in six synthetic femurs approximately 6 cm proximal to the knee joint. There were two constructs investigated: group 1 and group 2 were stabilized with an 8-hole LC-DCP, medially and laterally, respectively. Both construct groups were axially loaded. Global displacement (total length), wedge displacement, bending moment and strain were measured. Medial plating showed a significantly decreased displacement, bending moment and strain at the fracture site in axial loading. Medial plating of a comminuted supracondylar femur fracture is more stable than lateral plating.

What Preoperative Radiographic Parameters Are Associated With Increased Medial Release in Total Knee Arthroplasty?

PubMed

Martin, J Ryan; Jennings, Jason M; Levy, Daniel L; Watters, Tyler Steven; Miner, Todd M; Dennis, Douglas A

2017-03-01

Preoperative varus deformity of the knee is a common malalignment in patients undergoing primary total knee arthroplasty (TKA). We are unaware of any studies that have correlated how various preoperative radiographic parameters can predict the amount of medial releases performed to achieve optimal coronal alignment and ligamentous balance. A retrospective review was performed on 67 patients who required at least a medial tibial reduction osteotomy (MTRO) during primary TKA to achieve coronal balance. This patient population was matched 1:1 to another cohort of TKA patients by age, gender, and body mass index who did not require an MTRO. A radiographic evaluation was used to compare the 2 cohorts. Preoperatively, the MTRO cohort was noted to have significantly increased varus tibiofemoral (86.12° vs 93.43°), tibial articular surface (85.79° vs 87.54°), and medial tibial articular surface angles (75.22° vs 85.34°) compared to the control cohort. The MTRO cohort had 3.13 mm of medial tibial offset and 9.06 mm of lateral joint space opening and the control cohort had 0.09 mm and 4.07 mm, respectively. The medial tibial articular surface angle and lateral joint space widening were statistically associated with the MTRO cohort. The final tibiofemoral angle in the MTRO cohort was 92.43° and was 93.40° in the control cohort. The MTRO cohort was noted to have several preoperative radiographic parameters that were significantly different than the control cohort. However, the medial tibial articular surface angle and lateral joint space widening were the only radiographic parameters that were statistically associated with requiring an MTRO. Copyright © 2016 Elsevier Inc. All rights reserved.

The Medial Paralemniscal Nucleus and Its Afferent Neuronal Connections in Rat

PubMed Central

VARGA, TAMÁS; PALKOVITS, MIKLÓS; USDIN, TED BJÖRN; DOBOLYI, ARPÁD

2009-01-01

Previously, we described a cell group expressing tuberoinfundibular peptide of 39 residues (TIP39) in the lateral pontomesencephalic tegmentum, and referred to it as the medial paralemniscal nucleus (MPL). To identify this nucleus further in rat, we have now characterized the MPL cytoarchitectonically on coronal, sagittal, and horizontal serial sections. Neurons in the MPL have a columnar arrangement distinct from adjacent areas. The MPL is bordered by the intermediate nucleus of the lateral lemniscus nucleus laterally, the oral pontine reticular formation medially, and the rubrospinal tract ventrally, whereas the A7 noradrenergic cell group is located immediately mediocaudal to the MPL. TIP39-immunoreactive neurons are distributed throughout the cytoarchitectonically defined MPL and constitute 75% of its neurons as assessed by double labeling of TIP39 with a fluorescent Nissl dye or NeuN. Furthermore, we investigated the neuronal inputs to the MPL by using the retrograde tracer cholera toxin B subunit. The MPL has afferent neuronal connections distinct from adjacent brain regions including major inputs from the auditory cortex, medial part of the medial geniculate body, superior colliculus, external and dorsal cortices of the inferior colliculus, periolivary area, lateral preoptic area, hypothalamic ventromedial nucleus, lateral and dorsal hypothalamic areas, subparafascicular and posterior intralaminar thalamic nuclei, periaqueductal gray, and cuneiform nucleus. In addition, injection of the anterograde tracer biotinylated dextran amine into the auditory cortex and the hypothalamic ventromedial nucleus confirmed projections from these areas to the distinct MPL. The afferent neuronal connections of the MPL suggest its involvement in auditory and reproductive functions. PMID:18770870

The medial paralemniscal nucleus and its afferent neuronal connections in rat.

PubMed

Varga, Tamás; Palkovits, Miklós; Usdin, Ted Björn; Dobolyi, Arpád

2008-11-10

Previously, we described a cell group expressing tuberoinfundibular peptide of 39 residues (TIP39) in the lateral pontomesencephalic tegmentum, and referred to it as the medial paralemniscal nucleus (MPL). To identify this nucleus further in rat, we have now characterized the MPL cytoarchitectonically on coronal, sagittal, and horizontal serial sections. Neurons in the MPL have a columnar arrangement distinct from adjacent areas. The MPL is bordered by the intermediate nucleus of the lateral lemniscus nucleus laterally, the oral pontine reticular formation medially, and the rubrospinal tract ventrally, whereas the A7 noradrenergic cell group is located immediately mediocaudal to the MPL. TIP39-immunoreactive neurons are distributed throughout the cytoarchitectonically defined MPL and constitute 75% of its neurons as assessed by double labeling of TIP39 with a fluorescent Nissl dye or NeuN. Furthermore, we investigated the neuronal inputs to the MPL by using the retrograde tracer cholera toxin B subunit. The MPL has afferent neuronal connections distinct from adjacent brain regions including major inputs from the auditory cortex, medial part of the medial geniculate body, superior colliculus, external and dorsal cortices of the inferior colliculus, periolivary area, lateral preoptic area, hypothalamic ventromedial nucleus, lateral and dorsal hypothalamic areas, subparafascicular and posterior intralaminar thalamic nuclei, periaqueductal gray, and cuneiform nucleus. In addition, injection of the anterograde tracer biotinylated dextran amine into the auditory cortex and the hypothalamic ventromedial nucleus confirmed projections from these areas to the distinct MPL. The afferent neuronal connections of the MPL suggest its involvement in auditory and reproductive functions. (c) 2008 Wiley-Liss, Inc.

Meniscus delivery: a maneuver for easy arthroscopic access to the posterior horn of the medial meniscus.

PubMed

Said, Hatem Galal; Goyal, Saumitra; Fetih, Tarek Nabil

2016-03-16

Pathology of posterior horn of medial meniscus is common and often presents a difficult approach during arthroscopy for various reasons. We describe an easy maneuver to facilitate "delivery of the medial meniscus" during arthroscopy.

Exertional compartment syndrome of the medial foot compartment--diagnosis and treatment: a case report.

PubMed

Izadi, Faye E; Richie, Douglas H

2014-07-01

Exertional compartment syndrome in the foot is rarely reported and often confused with plantar fasciitis as a cause of arch pain in the running athlete. We describe a case involving a 19-year-old competitive collegiate runner who developed a chronic case of bilateral medial arch pain during training, which was initially diagnosed as plantar fasciitis but failed to respond to conventional treatment. After symptoms began to suggest exertional compartment syndrome, the diagnosis was confirmed by measuring an elevated resting pressure in the medial compartment of both feet. The patient underwent a bilateral medial compartment fasciotomy, which allowed a full return to activity, and has remained pain free after a 1-year follow-up.

Radiosurgery for Medial Temporal Lobe Epilepsy Resulting from Mesial Temporal Sclerosis.

PubMed

Gianaris, Thomas; Witt, Thomas; Barbaro, Nicholas M

2016-01-01

Medial temporal lobe epilepsy associated with mesial temporal sclerosis (MTS) is perhaps the most well-defined epilepsy syndrome that is responsive to structural interventions such as surgery. Several minimally invasive techniques have arisen that provide additional options for the treatment of MTS while potentially avoiding many of open surgery's associated risks. By evading these risks, they also open up treatment options to patients who otherwise are poor surgical candidates. Radiosurgery is one of the most intensively studied of these alternatives and has found a growing role in the treatment of medial temporal lobe epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

Extrusion of the medial meniscus in knee osteoarthritis assessed with a rotating clino-orthostatic permanent-magnet MRI scanner.

PubMed

Paparo, Francesco; Revelli, Matteo; Piccazzo, Riccardo; Astengo, Davide; Camellino, Dario; Puntoni, Matteo; Muda, Alessandro; Rollandi, Gian Andrea; Garlaschi, Giacomo; Cimmino, Marco Amedeo

2015-04-01

The objectives of this study were to assess the influence of weight-bearing on tibiofemoral osteoarthritis, including medial meniscal extrusion, by using a low-field (0.25 T) rotating clino-orthostatic permanent-magnet magnetic resonance (MR) scanner, and to analyse correlations of medial meniscal extrusion with the patient's Kellgren-Lawrence score, body mass index, and all the osteoarthritis features of the WORMS scoring system. Twenty-six patients (69.2% women and 30.8% men; mean age 67 ± 9.7 years) with medial tibiofemoral knee osteoarthritis were prospectively enrolled and MR sequences were acquired in both clino- and orthostatic position. MR images were assessed by two independent radiologists, according to the WORMS scale. Medial meniscal extrusion was measured and its clino-orthostatic difference (∆MME) was calculated. Intra- and inter-observer agreement of the WORMS Global Score readings was high by Cohen's K test (>0.81). No significant clino-orthostatic changes in the scoring parameters of the medial tibiofemoral joint were shown by Wilcoxon's test. Medial meniscal extrusion measured on orthostatic images was significantly higher than that measured in clinostatic position (p < 0.0001). At univariate analysis, the Kellgren-Lawrence score, WORMS Global Score, cartilage loss, meniscal damage, and osteophytes were significantly correlated to ∆MME (p < 0.005). Using a multiple regression model, tibiofemoral cartilage loss was found to correlate independently with ∆MME (p = 0.0499). Medial meniscal extrusion, evaluated with an open-configuration, rotating MR scanner, increased from the clinostatic to the orthostatic position. ∆MME, a new meniscal parameter, correlated with several important features of medial tibiofemoral osteoarthritis.

Dopamine in the medial amygdala network mediates human bonding

PubMed Central

Touroutoglou, Alexandra; Rudy, Tali; Salcedo, Stephanie; Feldman, Ruth; Hooker, Jacob M.; Dickerson, Bradford C.; Catana, Ciprian; Barrett, Lisa Feldman

2017-01-01

Research in humans and nonhuman animals indicates that social affiliation, and particularly maternal bonding, depends on reward circuitry. Although numerous mechanistic studies in rodents demonstrated that maternal bonding depends on striatal dopamine transmission, the neurochemistry supporting maternal behavior in humans has not been described so far. In this study, we tested the role of central dopamine in human bonding. We applied a combined functional MRI-PET scanner to simultaneously probe mothers’ dopamine responses to their infants and the connectivity between the nucleus accumbens (NAcc), the amygdala, and the medial prefrontal cortex (mPFC), which form an intrinsic network (referred to as the “medial amygdala network”) that supports social functioning. We also measured the mothers’ behavioral synchrony with their infants and plasma oxytocin. The results of this study suggest that synchronous maternal behavior is associated with increased dopamine responses to the mother’s infant and stronger intrinsic connectivity within the medial amygdala network. Moreover, stronger network connectivity is associated with increased dopamine responses within the network and decreased plasma oxytocin. Together, these data indicate that dopamine is involved in human bonding. Compared with other mammals, humans have an unusually complex social life. The complexity of human bonding cannot be fully captured in nonhuman animal models, particularly in pathological bonding, such as that in autistic spectrum disorder or postpartum depression. Thus, investigations of the neurochemistry of social bonding in humans, for which this study provides initial evidence, are warranted. PMID:28193868

Dopamine in the medial amygdala network mediates human bonding.

PubMed

Atzil, Shir; Touroutoglou, Alexandra; Rudy, Tali; Salcedo, Stephanie; Feldman, Ruth; Hooker, Jacob M; Dickerson, Bradford C; Catana, Ciprian; Barrett, Lisa Feldman

2017-02-28

Research in humans and nonhuman animals indicates that social affiliation, and particularly maternal bonding, depends on reward circuitry. Although numerous mechanistic studies in rodents demonstrated that maternal bonding depends on striatal dopamine transmission, the neurochemistry supporting maternal behavior in humans has not been described so far. In this study, we tested the role of central dopamine in human bonding. We applied a combined functional MRI-PET scanner to simultaneously probe mothers' dopamine responses to their infants and the connectivity between the nucleus accumbens (NAcc), the amygdala, and the medial prefrontal cortex (mPFC), which form an intrinsic network (referred to as the "medial amygdala network") that supports social functioning. We also measured the mothers' behavioral synchrony with their infants and plasma oxytocin. The results of this study suggest that synchronous maternal behavior is associated with increased dopamine responses to the mother's infant and stronger intrinsic connectivity within the medial amygdala network. Moreover, stronger network connectivity is associated with increased dopamine responses within the network and decreased plasma oxytocin. Together, these data indicate that dopamine is involved in human bonding. Compared with other mammals, humans have an unusually complex social life. The complexity of human bonding cannot be fully captured in nonhuman animal models, particularly in pathological bonding, such as that in autistic spectrum disorder or postpartum depression. Thus, investigations of the neurochemistry of social bonding in humans, for which this study provides initial evidence, are warranted.

Medial-lateral organization of the orbitofrontal cortex.

PubMed

Rich, Erin L; Wallis, Jonathan D

2014-07-01

Emerging evidence suggests that specific cognitive functions localize to different subregions of OFC, but the nature of these functional distinctions remains unclear. One prominent theory, derived from human neuroimaging, proposes that different stimulus valences are processed in separate orbital regions, with medial and lateral OFC processing positive and negative stimuli, respectively. Thus far, neurophysiology data have not supported this theory. We attempted to reconcile these accounts by recording neural activity from the full medial-lateral extent of the orbital surface in monkeys receiving rewards and punishments via gain or loss of secondary reinforcement. We found no convincing evidence for valence selectivity in any orbital region. Instead, we report differences between neurons in central OFC and those on the inferior-lateral orbital convexity, in that they encoded different sources of value information provided by the behavioral task. Neurons in inferior convexity encoded the value of external stimuli, whereas those in OFC encoded value information derived from the structure of the behavioral task. We interpret these results in light of recent theories of OFC function and propose that these distinctions, not valence selectivity, may shed light on a fundamental organizing principle for value processing in orbital cortex.

Medial prefrontal aberrations in major depressive disorder revealed by cytoarchitectonically informed voxel-based morphometry

PubMed Central

Bludau, Sebastian; Bzdok, Danilo; Gruber, Oliver; Kohn, Nils; Riedl, Valentin; Sorg, Christian; Palomero-Gallagher, Nicola; Müller, Veronika I.; Hoffstaedter, Felix; Amunts, Katrin; Eickhoff, Simon B.

2017-01-01

Objective The heterogeneous human frontal pole has been identified as a node in the dysfunctional network of major depressive disorder. The contribution of the medial (socio-affective) versus lateral (cognitive) frontal pole to major depression pathogenesis is currently unclear. The present study performs morphometric comparison of the microstructurally informed subdivisions of human frontal pole between depressed patients and controls using both uni- and multivariate statistics. Methods Multi-site voxel- and region-based morphometric MRI analysis of 73 depressed patients and 73 matched controls without psychiatric history. Frontal pole volume was first compared between depressed patients and controls by subdivision-wise classical morphometric analysis. In a second approach, frontal pole volume was compared by subdivision-naive multivariate searchlight analysis based on support vector machines. Results Subdivision-wise morphometric analysis found a significantly smaller medial frontal pole in depressed patients with a negative correlation of disease severity and duration. Histologically uninformed multivariate voxel-wise statistics provided converging evidence for structural aberrations specific to the microstructurally defined medial area of the frontal pole in depressed patients. Conclusions Across disparate methods, we demonstrated subregion specificity in the left medial frontal pole volume in depressed patients. Indeed, the frontal pole was shown to structurally and functionally connect to other key regions in major depression pathology like the anterior cingulate cortex and the amygdala via the uncinate fasciculus. Present and previous findings consolidate the left medial portion of the frontal pole as particularly altered in major depression. PMID:26621569

Posterior horn instability of the medial meniscus a sign of posterior meniscotibial ligament insufficiency.

PubMed

Mariani, P P

2011-07-01

In longstanding chronic anterior cruciate ligament (ACL) insufficiency, we identified an abnormal movement of the posterior medial meniscal horn, likely due to insufficiency of the posteromedial meniscotibial ligament. Passing from extension to flexion or vice versa, the medial posterior horn slides below the posterior rim of the tibia exposing the tibial plateau. Fixation with suture anchors of the meniscotibial ligament through a posteromedial portal restored normal meniscotibial tension and reduced instability of the meniscal posterior horn. The purpose of the present study was to present the arthroscopic features of posterior medial meniscus instability and to report results following arthroscopic repair. During the two-year study period, from 2007 through 2008, this arthroscopic feature was detected in 12 patients, 5 patients had failure of a previous ACL reconstruction and 7 patients had delay in ligamentous reconstruction for various reasons. All patients were affected by severe anterior-posterior translation with 11.3 ± 4.3 mm of side-to-side difference at KT-2000 and by associated rotatory laxity with grade 3 of pivot shift. At follow-up of 1 year, the combined ACL reconstruction and fixation of the posteromedial horn showed a reduction in the rotatory and anteroposterior laxity. This study suggests the importance of a proper arthroscopic evaluation of the posterior medial capsule in patients with chronic ACL insufficiency and highlights the potential presence of an unstable posterior horn of the medial meniscus as an indirect arthroscopic sign of peripheral laxity.

Posterior horn medial meniscal root repair with cruciate ligament/medial collateral ligament combined injuries.

PubMed

Wilson, Brian F; Johnson, Darren L

2011-12-01

Many meniscal root tears remain unrepaired, potentially due to under-recognition and the technical challenge of repairing them. A great effort is made to preserve the native meniscus and restore the circumferential fibers for hoop stress resistance. It has been well demonstrated in the literature that failure to repair this will lead to increased contact pressures in the medial compartment and early degenerative changes in the articular cartilage. Our technique is one that allows the meniscus to resume its important role of knee stability. A thorough understanding of meniscal root anatomy, as well as repair techniques, is important for the cruciate ligament surgeon. Copyright © 2011, SLACK Incorporated.

Medial Temporal Lobe Memory in Childhood: Developmental Transitions

ERIC Educational Resources Information Center

Townsend, Elise L.; Richmond, Jenny L.; Vogel-Farley, Vanessa K.; Thomas, Kathleen

2010-01-01

The medial temporal lobes (MTL) support declarative memory and mature structurally and functionally during the postnatal years in humans. Although recent work has addressed the development of declarative memory in early childhood, less is known about continued development beyond this period of time. The purpose of this investigation was to explore…

Effects of medial meniscus posterior horn avulsion and repair on tibiofemoral contact area and peak contact pressure with clinical implications.

PubMed

Marzo, John M; Gurske-DePerio, Jennifer

2009-01-01

Avulsion of the posterior horn attachment of the medial meniscus can compromise load-bearing ability, produce meniscus extrusion, and result in tibiofemoral joint-space narrowing, articular cartilage damage, and osteoarthritis. Avulsion of the posterior horn of the medial meniscus will increase peak contact pressure and decrease contact area in the medial compartment of the knee, and posterior horn repair will restore contact area and peak contact pressures to values of the control knee. Controlled laboratory study. Eight fresh-frozen human cadaveric knees had tibiofemoral peak contact pressures and contact area measured in the control state. The posterior horn of the medial meniscus was avulsed from its insertion and knees were retested. The meniscal avulsion was repaired by suture through a transosseous tunnel and the knees were tested a third time. Avulsion of the posterior horn attachment of the medial meniscus resulted in a significant increase in medial joint peak contact pressure (from 3841 kPa to 5084 kPa) and a significant decrease in contact area (from 594 mm(2) to 474 mm(2)). Repair of the avulsion resulted in restoration of the loading profiles to values equal to the control knee, with values of 3551 kPa for peak pressure and 592 mm(2) for contact area. Posterior horn medial meniscal root avulsion leads to deleterious alteration of the loading profiles of the medial joint compartment and results in loss of hoop stress resistance, meniscus extrusion, abnormal loading of the joint, and early knee medial-compartment degenerative changes. The repair technique described restores the ability of the medial meniscus to absorb hoop stress and eliminate joint-space narrowing, possibly decreasing the risk of degenerative disease.

Arthroscopic partial meniscectomy of a posteriorly flipped superior leaflet in a horizontal medial meniscus tear using a posterior transseptal portal.

PubMed

Jang, Ki-Mo; Ahn, Jin Hwan; Wang, Joon Ho

2012-03-07

This article describes a case of an arthroscopic partial meniscectomy of a posteriorly flipped superior leaflet in a horizontal medial meniscus tear using the posterior transseptal portal. An arthroscopic partial meniscectomy for bucket handle or flap tears in medial or lateral compartments using ordinary portals is a relatively common procedure in irreparable cases. However, the posterior compartment of the knee is not readily accessible through ordinary arthroscopic portals. Therefore, it has been considered a blind spot. Through the posterior transseptal portal, surgeons can achieve excellent arthroscopic visualization of the posterior compartment and easily perform arthroscopic procedures of the posterior compartment of the knee. A 48-year-old woman presented with a 1-year history of pain in the medial aspect of the right knee joint. Preoperative magnetic resonance imaging revealed a thinning of the medial meniscus posterior horn in coronal images and a sharp-edged triangle arising from the medial meniscus posterior horn between the medial femoral condyle and medial meniscus posterior horn on sagittal images (flipped-over sign). During the arthroscopic procedure, we found that the flipped leaflet was displaced posteriorly and was not mobile between the medial femoral condyle and medial meniscus posterior horn. Partial meniscectomy for a posteriorly displaced fragment can be performed successfully using the posterior transseptal portal. The posterior transseptal portal is useful for an arthroscopic partial meniscectomy of a posteriorly flipped leaflet in the posterior compartment of the knee. Copyright 2012, SLACK Incorporated.

Tibial Tray Thickness Significantly Increases Medial Tibial Bone Resorption in Cobalt-Chromium Total Knee Arthroplasty Implants.

PubMed

Martin, J Ryan; Watts, Chad D; Levy, Daniel L; Miner, Todd M; Springer, Bryan D; Kim, Raymond H

2017-01-01

Stress shielding is an uncommon complication associated with primary total knee arthroplasty. Patients are frequently identified radiographically with minimal clinical symptoms. Very few studies have evaluated risk factors for postoperative medial tibial bone loss. We hypothesized that thicker cobalt-chromium tibial trays are associated with increased bone loss. We performed a retrospective review of 100 posterior stabilized, fixed-bearing total knee arthroplasty where 50 patients had a 4-mm-thick tibial tray (thick tray cohort) and 50 patients had a 2.7-mm-thick tibial tray (thin tray cohort). A clinical evaluation and a radiographic assessment of medial tibial bone loss were performed on both cohorts at a minimum of 2 years postoperatively. Mean medial tibial bone loss was significantly higher in the thick tray cohort (1.07 vs 0.16 mm; P = .0001). In addition, there were significantly more patients with medial tibial bone loss in the thick tray group compared with the thin tray group (44% vs 10%, P = .0002). Despite these differences, there were no statistically significant differences in range of motion, knee society score, complications, or revision surgeries performed. A thicker cobalt-chromium tray was associated with significantly more medial tibial bone loss. Despite these radiographic findings, we found no discernable differences in clinical outcomes in our patient cohort. Further study and longer follow-up are needed to understand the effects and clinical significance of medial tibial bone loss. Copyright © 2016 Elsevier Inc. All rights reserved.

Unicameral Bone Cyst of the Medial Cuneiform.

PubMed

Schick, Faith A; Daniel, Joseph N; Miller, Juliane S

2016-09-02

A unicameral bone cyst is a relatively uncommon, benign bone tumor found in the metaphysis of long bones, such as the humerus and the femur, in skeletally immature persons. In the foot, these benign, fluid-filled cavities are most commonly found within the os calcis. We present a case report of a 10-year-old female with a unicameral bone cyst of the medial cuneiform.

Estrogen Receptor-α in the Medial Amygdala Prevents Stress-Induced Elevations in Blood Pressure in Females.

PubMed

Hinton, Antentor Othrell; He, Yanlin; Xia, Yan; Xu, Pingwen; Yang, Yongjie; Saito, Kenji; Wang, Chunmei; Yan, Xiaofeng; Shu, Gang; Henderson, Alexander; Clegg, Deborah J; Khan, Sohaib A; Reynolds, Corey; Wu, Qi; Tong, Qingchun; Xu, Yong

2016-06-01

Psychological stress contributes to the development of hypertension in humans. The ovarian hormone, estrogen, has been shown to prevent stress-induced pressor responses in females by unknown mechanisms. Here, we showed that the antihypertensive effects of estrogen during stress were blunted in female mice lacking estrogen receptor-α in the brain medial amygdala. Deletion of estrogen receptor-α in medial amygdala neurons also resulted in increased excitability of these neurons, associated with elevated ionotropic glutamate receptor expression. We further demonstrated that selective activation of medial amygdala neurons mimicked effects of stress to increase blood pressure in mice. Together, our results support a model where estrogen acts on estrogen receptor-α expressed by medial amygdala neurons to prevent stress-induced activation of these neurons, and therefore prevents pressor responses to stress. © 2016 American Heart Association, Inc.

Estrogens and their receptors in the medial amygdala rapidly facilitate social recognition in female mice.

PubMed

Lymer, Jennifer M; Sheppard, Paul A S; Kuun, Talya; Blackman, Andrea; Jani, Nilay; Mahbub, Sahnon; Choleris, Elena

2018-03-01

Estrogens have been shown to rapidly (within 1 h) affect learning and memory processes, including social recognition. Both systemic and hippocampal administration of 17β-estradiol facilitate social recognition in female mice within 40 min of administration. These effects were likely mediated by estrogen receptor (ER) α and the G-protein coupled estrogen receptor (GPER), as administration of the respective receptor agonists (PPT and G-1) also facilitated social recognition on a rapid time scale. The medial amygdala has been shown to be necessary for social recognition and long-term manipulations in rats have implicated medial amygdalar ERα. As such, our objective was to investigate whether estrogens and different ERs within the medial amygdala play a role in the rapid facilitation of social recognition in female mice. 17β-estradiol, G-1, PPT, or ERβ agonist DPN was infused directly into the medial amygdala of ovariectomized female mice. Mice were then tested in a social recognition paradigm, which was completed within 40 min, thus allowing the assessment of rapid effects of treatments. 17β-estradiol (10, 25, 50, 100 nM), PPT (300 nM), DPN (150 nM), and G-1 (50 nM) each rapidly facilitated social recognition. Therefore, estrogens in the medial amygdala rapidly facilitate social recognition in female mice, and the three main estrogen receptors: ERα, ERβ, and the GPER all are involved in these effects. This research adds to a network of brain regions, including the medial amygdala and the dorsal hippocampus, that are involved in mediating the rapid estrogenic facilitation of social recognition in female mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ductal plate malformation in patients with biliary atresia.

PubMed

Vuković, Jurica; Grizelj, Ruža; Bojanić, Katarina; Corić, Marijana; Luetić, Tomislav; Batinica, Stipe; Kujundžić-Tiljak, Mirjana; Schroeder, Darrell R; Sprung, Juraj

2012-12-01

The presence of ductal plate malformation (DPM+) on liver histology in children with biliary atresia (BA) is a marker of early intrauterine disease onset and an indication of an unfavorable prognosis. We studied the prognostic value of DPM in infants with BA after hepatoportoenterostomy (HPE). We reviewed 28 BA patients who underwent HPE in a single medical center. We examined the time of jaundice onset after delivery (conjugated hyperbilirubinemia): early onset (fetal phenotype with no jaundice-free interval) vs. late onset (perinatal phenotype with jaundice-free interval) and the presence or absence of DPM (DPM+ or DPM-) histopathology. Primary outcome was jaundice clearance at 3 months after HPE and survival with native liver (SNL). Eight children had fetal and 20 had perinatal BA (8 DPM+, 12 DPM-). At 3 months after HPE, no patients with fetal BA had achieved jaundice clearance, while jaundice clearance was achieved in five patients with DPM+ perinatal disease and four patients with DPM- perinatal BA (P = 0.03, comparing all three groups; P = 0.36, comparing DPM+ vs. DPM- perinatal patients). Median SNL was 8.6 months for fetal BA patients, 148.2 months for DPM+ perinatal BA patients, and 93.2 months for DPM- perinatal BA patients (log-rank test, P < 0.001, comparing all three groups; P = 0.59, comparing DPM+ vs. DPM- perinatal patients). After adjusting for BA type, age older than 2 months at HPE was associated with worse SNL [P = 0.03; hazard ratio = 4.0 (95 % CI, 1.1-14.2)]. Early onset of jaundice, regardless of DPM histology, was the most ominous sign of poor outcome in infants with BA after HPE.

Meta-analysis of posterior versus medial approach for popliteal artery aneurysm repair.

PubMed

Phair, Alison; Hajibandeh, Shahin; Hajibandeh, Shahab; Kelleher, Damian; Ibrahim, Riza; Antoniou, George A

2016-10-01

Popliteal artery aneurysm is an uncommon vascular disease but one that can cause significant morbidity, the most severe being limb loss reported in 20% to 59% of cases. Two approaches to repair are described in the literature, the posterior and the medial; however, the "gold standard" method of repair remains controversial. A systematic review of electronic information sources was undertaken to identify papers comparing outcomes of posterior repair vs medial repair. The methodologic quality of the papers was assessed using the Newcastle-Ottawa Scale. Fixed-effect or random-effects models were applied to synthesize data. The search yielded seven articles eligible for inclusion. The total population comprised 1427 patients; 338 had posterior repair and 1089 had medial repair. There was no difference in the two groups in terms of postoperative nerve damage (odds ratio [OR], 1.01; 95% confidence interval [CI], 0.24-4.2) and 30-day postoperative complications (OR, 0.87; 95% CI, 0.43-1.77). Limb loss at 30 days occurred more frequently in the medial approach group, but the difference was not statistically significant (risk difference [RD], 0.02; 95% CI, -0.04 to 0.00). Thirty-day primary patency was not statistically different between groups (RD, -0.01; 95% CI, -0.04 to 0.02), but the 30-day secondary patency suggested superiority of the posterior approach (RD, 0.05; 95% CI, 0.02-0.07). Long-term primary and secondary patency both favored the posterior approach (OR, 1.61 [95% CI, 1.06-2.43] and OR, 1.73 [95% CI, 0.91-3.30], respectively). Aneurysm exclusion was also superior with the posterior approach (OR, 4.20; 95% CI, 1.40-12.60). The rate of reoperation favored the posterior approach (OR, 0.26; 95% CI, 0.09-0.72). Long-term risk of limb loss favored posterior repair, but no statistically significant difference was found (OR, 0.32; 95% CI, 0.43-1.77). High-level comparative data comparing posterior and medial repair for popliteal artery aneurysms are not available

Medialized repair for retracted rotator cuff tears.

PubMed

Kim, Young-Kyu; Jung, Kyu-Hak; Won, Jun-Sung; Cho, Seung-Hyun

2017-08-01

The purpose of this study was to evaluate the functional outcomes of medialized rotator cuff repair and the continuity of repaired tendon in chronic retracted rotator cuff tears. Thirty-five consecutive patients were selected from 153 cases that underwent arthroscopic rotator cuff repair for more than medium-sized posterosuperior rotator cuff tears between July 2009 and July 2012 performed with the medialized repair. All cases were available for at least 2 years of postoperative follow-up. The visual analog scale of pain, muscle strength, Constant score, American Shoulder and Elbow Surgeons (ASES) score, and University of California-Los Angeles score were evaluated. At the final follow-up, all clinical outcomes were significantly improved. The visual analog scale score for pain improved from 6 ± 1 preoperatively to 2 ± 1 postoperatively. The range of motion increased from preoperatively to postoperatively: active forward elevation, from 134° ± 49° to 150° ± 16°; active external rotation at the side, from 47° ± 15° to 55° ± 10°; and active internal rotation, from L3 to L1. The shoulder score also improved: Constant score, from 53.5 ± 16.7 to 79 ± 10; American Shoulder and Elbow Surgeons score, from 51 ± 15 to 82 ± 8; and University of California-Los Angeles score, from 14 ± 4 to 28 ± 4. The retear cases at the final follow-up were 6 (17%). Medialized repair may be useful in cases in which anatomic bone-to-tendon repair would be difficult because of the excessive tension of the repaired tendon and a torn tendon that does not reach the anatomic insertion. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Distinct medial temporal networks encode surprise during motivation by reward versus punishment

PubMed Central

Murty, Vishnu P.; LaBar, Kevin S.; Adcock, R. Alison

2016-01-01

Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also impacts neural and mnemonic encoding of surprising events. During functional magnetic resonance imaging (fMRI), participants encountered perceptually unexpected events either during the pursuit of rewards or avoidance of punishments. Despite similar levels of motivation across groups, reward and punishment facilitated the processing of surprising events in different medial temporal lobe regions. Whereas during reward motivation, perceptual surprises enhanced activation in the hippocampus, during punishment motivation surprises instead enhanced activation in parahippocampal cortex. Further, we found that reward motivation facilitated hippocampal coupling with ventromedial PFC, whereas punishment motivation facilitated parahippocampal cortical coupling with orbitofrontal cortex. Behaviorally, post-scan testing revealed that reward, but not punishment, motivation resulted in greater memory selectivity for surprising events encountered during goal pursuit. Together these findings demonstrate that neuromodulatory systems engaged by anticipation of reward and punishment target separate components of the medial temporal lobe, modulating medial temporal lobe sensitivity and connectivity. Thus, reward and punishment motivation yield distinct neural contexts for learning, with distinct consequences for how surprises are incorporated into predictive mnemonic models of the environment. PMID:26854903

Distinct medial temporal networks encode surprise during motivation by reward versus punishment.

PubMed

Murty, Vishnu P; LaBar, Kevin S; Adcock, R Alison

2016-10-01

Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also impacts neural and mnemonic encoding of surprising events. During functional magnetic resonance imaging (fMRI), participants encountered perceptually unexpected events either during the pursuit of rewards or avoidance of punishments. Despite similar levels of motivation across groups, reward and punishment facilitated the processing of surprising events in different medial temporal lobe regions. Whereas during reward motivation, perceptual surprises enhanced activation in the hippocampus, during punishment motivation surprises instead enhanced activation in parahippocampal cortex. Further, we found that reward motivation facilitated hippocampal coupling with ventromedial PFC, whereas punishment motivation facilitated parahippocampal cortical coupling with orbitofrontal cortex. Behaviorally, post-scan testing revealed that reward, but not punishment, motivation resulted in greater memory selectivity for surprising events encountered during goal pursuit. Together these findings demonstrate that neuromodulatory systems engaged by anticipation of reward and punishment target separate components of the medial temporal lobe, modulating medial temporal lobe sensitivity and connectivity. Thus, reward and punishment motivation yield distinct neural contexts for learning, with distinct consequences for how surprises are incorporated into predictive mnemonic models of the environment. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical Outcome of Medial Pivot Compared With Press-Fit Condylar Sigma Cruciate-Retaining Mobile-Bearing Total Knee Arthroplasty.

PubMed

Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik

2017-10-01

The purpose of this study was to compare the long-term clinical results, radiographic results, range of knee motion, patient satisfaction, and the survival rate of Medial-Pivot posterior cruciate-substituting, knee prosthesis and a press-fit condylar (PFC) Sigma cruciate-retaining mobile-bearing knee prosthesis in the same patients. One hundred eighty-two patients received Medial-Pivot knee prosthesis in one knee and a PFC Sigma knee prosthesis in the contralateral knee. The minimum duration of follow-up was 11 years (range, 11-12.6 years). The knees with a Medial-Pivot knee prosthesis had significantly worse results than those with a PFC Sigma knee prosthesis at the final follow-up with regard to the mean postoperative Knee Society knee scores (90 compared with 95 points), Western Ontario and McMaster Universities Osteoarthritis Index score (25 compared with 18 points), and range of knee motion (117° compared with 128°). Patients were more satisfied with PFC Sigma knee prosthesis (93%) than with Medial-Pivot knee prosthesis (75%). Complication rates were significantly higher in the Medial-Pivot knee group (26%) than those in the PFC Sigma knee group (6.5%). Radiographic results and survival rates (99% compared with 99.5%) were similar between the 2 groups. Although the long-term fixation and survival rate of both Medial-Pivot and PFC Sigma prostheses were similar, we observed a worse knee score, worse range of knee motion, and patient satisfaction was less in the Medial-Pivot knee group than in the PFC Sigma knee group. Furthermore, complication rate was also higher in the Medial-Pivot knee group than the other group. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of medial parapatellar nail insertion on alignment in proximal tibia fractures--special consideration of the fracture level.

PubMed

Weninger, Patrick; Tschabitscher, Manfred; Traxler, Hannes; Pfafl, Veronika; Hertz, Harald

2010-04-01

Although a lateral starting point for tibial nailing is recommended to avoid valgus misalignment, higher rates of intra-articular damage were described compared with a medial parapatellar approach. The aim of this anatomic study was to evaluate the fracture level allowing for a safe medial nail entry point without misalignment or dislocation of fragments. Thirty-two fresh-frozen cadaver lower extremities were used to create 1-cm osteotomies at four different levels (n = 8) from 2 cm to 8 cm below the tibial tuberosity. Nine-millimeter unreamed solid titanium tibial nails (Connex, I.T.S. Spectromed, Lassnitzhohe, Austria) were inserted from a medial parapatellar incision. Misalignment (degree) and dislocation of the distal fragment were measured in the frontal and sagittal plane. A medial parapatellar approach for tibial nail insertion mainly caused valgus and anterior bow misalignment and ventral and medial fragment displacement. Mean misalignment and fragment displacement did not exceed 0.5 degree if the osteotomy was performed 8 cm to 9 cm below the tibial tuberosity. According to the results of this study, a medial parapatellar approach can be performed without misalignment and fragment dislocation in proximal tibia fractures extending 8 cm or more below the tibial tuberosity.

Augmentation of the Pullout Repair of a Medial Meniscus Posterior Root Tear by Arthroscopic Centralization.

PubMed

Koga, Hideyuki; Watanabe, Toshifumi; Horie, Masafumi; Katagiri, Hiroki; Otabe, Koji; Ohara, Toshiyuki; Katakura, Mai; Sekiya, Ichiro; Muneta, Takeshi

2017-08-01

The meniscus roots are critical for meniscus function in preserving correct knee kinematics and avoiding meniscus extrusion and, consequently, in the progression of osteoarthritis. Several techniques exist for medial meniscus posterior root tear repair; however, current surgical techniques have been proved to fail to reduce meniscus extrusion, which has been shown to be associated with development of osteoarthritis, although significant improvements in the postoperative clinical findings have been achieved. This Technical Note describes an arthroscopic technique for the medial meniscus posterior root tear in which a pullout repair is augmented by a centralization technique to restore and maintain the medial meniscus function by efficiently reducing meniscus extrusion.

Lateral patellar retinaculum reconstruction for medial patellar instability following lateral retinacular release: a case report.

PubMed

Udagawa, Kazuhiko; Niki, Yasuo; Matsumoto, Hiroaki; Matsumoto, Hideo; Enomoto, Hiroyuki; Toyama, Yoshiaki; Suda, Yasunori

2014-01-01

Lateral retinacular release is still being performed in patients with recurrent patellar dislocation as an additional procedure with distal realignment or medial patellofemoral ligament (MPFL) reconstruction. However, consensus remains lacking regarding suitable indications for lateral retinacular release. A 20-year-old woman presented with patellar instability in both medial and lateral directions after undergoing lateral retinacular release with MPFL reconstruction. She displayed inherent systemic joint laxity meeting all seven Carter-Wilkinson criteria. Simultaneous MPFL revision and lateral retinaculum reconstruction successfully improved patellar instability in both directions. This case provides an example of iatrogenic medial patellar instability after failed lateral retinacular release. Copyright © 2013 Elsevier B.V. All rights reserved.

3D surface parameterization using manifold learning for medial shape representation

NASA Astrophysics Data System (ADS)

Ward, Aaron D.; Hamarneh, Ghassan

2007-03-01

The choice of 3D shape representation for anatomical structures determines the effectiveness with which segmentation, visualization, deformation, and shape statistics are performed. Medial axis-based shape representations have attracted considerable attention due to their inherent ability to encode information about the natural geometry of parts of the anatomy. In this paper, we propose a novel approach, based on nonlinear manifold learning, to the parameterization of medial sheets and object surfaces based on the results of skeletonization. For each single-sheet figure in an anatomical structure, we skeletonize the figure, and classify its surface points according to whether they lie on the upper or lower surface, based on their relationship to the skeleton points. We then perform nonlinear dimensionality reduction on the skeleton, upper, and lower surface points, to find the intrinsic 2D coordinate system of each. We then center a planar mesh over each of the low-dimensional representations of the points, and map the meshes back to 3D using the mappings obtained by manifold learning. Correspondence between mesh vertices, established in their intrinsic 2D coordinate spaces, is used in order to compute the thickness vectors emanating from the medial sheet. We show results of our algorithm on real brain and musculoskeletal structures extracted from MRI, as well as an artificial multi-sheet example. The main advantages to this method are its relative simplicity and noniterative nature, and its ability to correctly compute nonintersecting thickness vectors for a medial sheet regardless of both the amount of coincident bending and thickness in the object, and of the incidence of local concavities and convexities in the object's surface.

Downregulation of the posterior medial frontal cortex prevents social conformity.

PubMed

Klucharev, Vasily; Munneke, Moniek A M; Smidts, Ale; Fernández, Guillén

2011-08-17

We often change our behavior to conform to real or imagined group pressure. Social influence on our behavior has been extensively studied in social psychology, but its neural mechanisms have remained largely unknown. Here we demonstrate that the transient downregulation of the posterior medial frontal cortex by theta-burst transcranial magnetic stimulation reduces conformity, as indicated by reduced conformal adjustments in line with group opinion. Both the extent and probability of conformal behavioral adjustments decreased significantly relative to a sham and a control stimulation over another brain area. The posterior part of the medial frontal cortex has previously been implicated in behavioral and attitudinal adjustments. Here, we provide the first interventional evidence of its critical role in social influence on human behavior.

Effect of a pelvic wedge and belt on the medial and lateral hamstring muscles during knee flexion.

PubMed

Yoo, Won-Gyu

2017-01-01

[Purpose] This study developed a pelvic wedge and belt and investigated their effects on the selective activation of medial and lateral hamstring muscles during knee flexion. [Subjects and Methods] Nine adults were enrolled. The participants performed exercises without and with the pelvic wedge and belt, and the electromyographic activities of the medial and lateral hamstring muscles were recorded. [Results] The activity of the medial hamstring was increased significantly when using the pelvic wedge and belt, while the activity of the lateral hamstring did not differ significantly. [Conclusion] The pelvic wedge and belt provide a self-locked position during knee flexion in the prone position. Prone knee flexion in this position is an effective self-exercise for balanced strengthening of the medial hamstring.

Effect of a pelvic wedge and belt on the medial and lateral hamstring muscles during knee flexion

PubMed Central

Yoo, Won-gyu

2017-01-01

[Purpose] This study developed a pelvic wedge and belt and investigated their effects on the selective activation of medial and lateral hamstring muscles during knee flexion. [Subjects and Methods] Nine adults were enrolled. The participants performed exercises without and with the pelvic wedge and belt, and the electromyographic activities of the medial and lateral hamstring muscles were recorded. [Results] The activity of the medial hamstring was increased significantly when using the pelvic wedge and belt, while the activity of the lateral hamstring did not differ significantly. [Conclusion] The pelvic wedge and belt provide a self-locked position during knee flexion in the prone position. Prone knee flexion in this position is an effective self-exercise for balanced strengthening of the medial hamstring. PMID:28210048

Biomechanical consequences of a tear of the posterior root of the medial meniscus. Similar to total meniscectomy.

PubMed

Allaire, Robert; Muriuki, Muturi; Gilbertson, Lars; Harner, Christopher D

2008-09-01

Tears of the posterior root of the medial meniscus are becoming increasingly recognized. They can cause rapidly progressive arthritis, yet their biomechanical effects are not understood. The goal of this study was to determine the effects of posterior root tears of the medial meniscus and their repairs on tibiofemoral joint contact pressure and kinematics. Nine fresh-frozen cadaver knees were used. An axial load of 1000 N was applied with a custom testing jig at each of four knee-flexion angles: 0 degrees, 30 degrees, 60 degrees, and 90 degrees. The knees were otherwise unconstrained. Four conditions were tested: (1) intact, (2) a posterior root tear of the medial meniscus, (3) a repaired posterior root tear, and (4) a total medial meniscectomy. Fuji pressure-sensitive film was used to record the contact pressure and area for each testing condition. Kinematic data were obtained by using a robotic arm to record the position of the knees for each loading condition. Three-dimensional knee kinematics were analyzed with custom programs with use of previously described transformations. The measured variables were axial rotation, varus angulation, lateral translation, and anterior translation. In the medial compartment, a posterior root tear of the medial meniscus caused a 25% increase in peak contact pressure compared with that found in the intact condition (p < 0.001). Repair restored the peak contact pressure to normal. No difference was detected between the peak contact pressure after the total medial meniscectomy and that associated with the root tear. The peak contact pressure in the lateral compartment after the total medial meniscectomy was up to 13% greater than that for all other conditions (p = 0.026). Significant increases in external rotation and lateral tibial translation, compared with the values in the intact knee, were observed in association with the posterior root tear (2.98 degrees and 0.84 mm, respectively) and the meniscectomy (4.45 degrees and 0

Editorial Commentary: Chondrocytes Trump Ligaments! Partial Release of the Medial Collateral Ligament During Knee Arthroscopy Protects Chondrocytes.

PubMed

Leland, J Martin

2016-10-01

With knee arthroscopy being the most common orthopaedic procedure performed in the United States, it is crucial to be able to access the entire knee without iatrogenic injury. Frequently orthopaedic surgeons encounter tight medial compartments, creating difficulty in accessing the posterior horn of the medial meniscus without damaging the articular cartilage. Partial release of the medial collateral ligament during knee arthroscopy protects chondrocytes. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Chevron-type medial malleolar osteotomy: a functional, radiographic and quantitative T2-mapping MRI analysis.

PubMed

Lamb, Joshua; Murawski, Christopher D; Deyer, Timothy W; Kennedy, John G

2013-06-01

The purpose of this study was to retrospectively evaluate a large series of patients for functional, radiographic and MRI outcomes after a Chevron-type medial malleolar osteotomy. Sixty-two patients underwent a Chevron-type medial malleolar osteotomy with a median follow-up of 34.5 months. Standard digital radiographs were used to determine bony union and the angle of the osteotomy relative to the longitudinal axis of the tibia. Morphologic and quantitative T2-mapping MRI was also analysed in 32 patients. Fifty-eight patients (94 %) reported being asymptomatic at the site of the medial malleolar osteotomy. The median time to healing on standard radiograph was 6 weeks (range, 4-6 weeks) with an angle of 31.7° ± 6.9°. Quantitative T2-mapping MRI analysis demonstrated that the deep half of interface repair tissue had relaxation times that were not significantly different from normal tibial cartilage. In contrast, interface repair tissue in the superficial half demonstrated significant prolongation from normal relaxation time values, indicating a more fibrocartilaginous repair. Four patients (6 %) reported pain post-operatively. A Chevron-type medial malleolar osteotomy demonstrates satisfactory healing and fixation, with fibrocartilaginous tissue evident superficially at the osteotomy interface. Further investigation is warranted in the form of longitudinal study to assess the long-term outcomes of medial malleolar osteotomy.

Endoscopic modified medial maxillectomy for treatment of inverted papilloma originating from the maxillary sinus.

PubMed

Erbek, Selim S; Koycu, Alper; Buyuklu, Fuat

2015-05-01

Endoscopic approaches have become an alternative to external approaches in the treatment of sinonasal inverted papillomas (IPs) in recent years. The aim of this study was to analyze the outcomes of endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate in selected IP cases. Medical charts of patients diagnosed with IP originating from the maxillary sinus between July 2008 and August 2013 were reviewed. Eight patients who had undergone endoscopic modified medial maxillectomy were included in the study. Attachment of IP was located on the medial wall of the maxillary sinus in all cases. The nasolacrimal duct was preserved in all of the patients. The inferior turbinate was completely preserved in 5 patients, and the anterior part of the inferior turbinate was preserved in 3 patients. The mean follow-up period of the patients was 30.8 months (12-60  mo). None of the patients had recurrence or major complications. The postoperative complaints were minor hemorrhagic discharge and crusting for the first few weeks. Endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate provides good surgical and functional outcomes in selected IP cases.

Experimental extraction of an entangled photon pair from two identically decohered pairs.

PubMed

Yamamoto, Takashi; Koashi, Masato; Ozdemir, Sahin Kaya; Imoto, Nobuyuki

2003-01-23

Entanglement is considered to be one of the most important resources in quantum information processing schemes, including teleportation, dense coding and entanglement-based quantum key distribution. Because entanglement cannot be generated by classical communication between distant parties, distribution of entangled particles between them is necessary. During the distribution process, entanglement between the particles is degraded by the decoherence and dissipation processes that result from unavoidable coupling with the environment. Entanglement distillation and concentration schemes are therefore needed to extract pairs with a higher degree of entanglement from these less-entangled pairs; this is accomplished using local operations and classical communication. Here we report an experimental demonstration of extraction of a polarization-entangled photon pair from two decohered photon pairs. Two polarization-entangled photon pairs are generated by spontaneous parametric down-conversion and then distributed through a channel that induces identical phase fluctuations to both pairs; this ensures that no entanglement is available as long as each pair is manipulated individually. Then, through collective local operations and classical communication we extract from the two decohered pairs a photon pair that is observed to be polarization-entangled.

Advanced atherosclerosis is associated with increased medial degeneration in sporadic ascending aortic aneurysms.

PubMed

Albini, Paul T; Segura, Ana Maria; Liu, Guanghui; Minard, Charles G; Coselli, Joseph S; Milewicz, Dianna M; Shen, Ying H; LeMaire, Scott A

2014-02-01

The pathogenesis of non-familial, sporadic ascending aortic aneurysms (SAAA) is poorly understood, and the relationship between ascending aortic atherosclerosis and medial degeneration is unclear. We evaluated the prevalence and severity of aortic atherosclerosis and its association with medial degeneration in SAAA. Atherosclerosis was characterized in ascending aortic tissues collected from 68 SAAA patients (mean age, 62.9 ± 12.0 years) and 15 controls (mean age, 56.6 ± 11.4 years [P = 0.07]) by using a modified American Heart Association classification system. Upon histologic examination, 97% of SAAA patients and 73% of controls showed atherosclerotic changes. Most SAAA samples had intermediate (types 2 and 3, 35%) or advanced atherosclerosis (types ≥ 4; 40%), whereas most control samples showed minimal atherosclerosis (none or type 1, 80%; P < 0.001 after adjusting for age). In a separate analysis, we examined the total incidence and grade distribution of medial degenerative changes among SAAA samples according to atherosclerosis grade. Advanced atherosclerosis was associated with higher grades of smooth muscle cell depletion (P < 0.001), elastic fiber depletion (P = 0.02), elastic fiber fragmentation (P < 0.001), and mucopolysaccharide accumulation (P = 0.04). Aortic diameter was larger in SAAA patients with advanced atherosclerosis than in patients with minimal (P = 0.04) or intermediate atherosclerosis (P = 0.04). Immunostaining showed marked CD3+ T-cell and CD68+ macrophage infiltration, MMP-2 and MMP-9 production, and cryopyrin expression in the medial layer adjacent to atherosclerotic plaque. SAAA tissues exhibited advanced atherosclerosis that was associated with severe medial degeneration and increased aortic diameter. Our findings suggest a role for atherosclerosis in the progression of sporadic ascending aortic aneurysms. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Structural covariance mapping delineates medial and medio-lateral temporal networks in déjà vu.

PubMed

Shaw, Daniel Joel; Mareček, Radek; Brázdil, Milan

2016-12-01

Déjà vu (DV) is an eerie phenomenon experienced frequently as an aura of temporal lobe epilepsy, but also reported commonly by healthy individuals. The former pathological manifestation appears to result from aberrant neural activity among brain structures within the medial temporal lobes. Recent studies also implicate medial temporal brain structures in the non-pathological experience of DV, but as one element of a diffuse neuroanatomical correlate; it remains to be seen if neural activity among the medial temporal lobes also underlies this benign manifestation. The present study set out to investigate this. Due to its unpredictable and infrequent occurrence, however, non-pathological DV does not lend itself easily to functional neuroimaging. Instead, we draw on research showing that brain structure covaries among regions that interact frequently as nodes of functional networks. Specifically, we assessed whether grey-matter covariance among structures implicated in non-pathological DV differs according to the frequency with which the phenomenon is experienced. This revealed two diverging patterns of structural covariation: Among the first, comprised primarily of medial temporal structures and the caudate, grey-matter volume becomes more positively correlated with higher frequency of DV experience. The second pattern encompasses medial and lateral temporal structures, among which greater DV frequency is associated with more negatively correlated grey matter. Using a meta-analytic method of co-activation mapping, we demonstrate a higher probability of functional interactions among brain structures constituting the former pattern, particularly during memory-related processes. Our findings suggest that altered neural signalling within memory-related medial temporal brain structures underlies both pathological and non-pathological DV.

Sensitivity of medial and lateral knee contact force predictions to frontal plane alignment and contact locations.

PubMed

Saliba, Christopher M; Brandon, Scott C E; Deluzio, Kevin J

2017-05-24

Musculoskeletal models are increasingly used to estimate medial and lateral knee contact forces, which are difficult to measure in vivo. The sensitivity of contact force predictions to modeling parameters is important to the interpretation and implication of results generated by the model. The purpose of this study was to quantify the sensitivity of knee contact force predictions to simultaneous errors in frontal plane knee alignment and contact locations under different dynamic conditions. We scaled a generic musculoskeletal model for N=23 subjects' stature and radiographic knee alignment, then perturbed frontal plane alignment and mediolateral contact locations within experimentally-possible ranges of 10° to -10° and 10 to -10mm, respectively. The sensitivity of first peak, second peak, and mean medial and lateral knee contact forces to knee adduction angle and contact locations was modeled using linear regression. Medial loads increased, and lateral loads decreased, by between 3% and 6% bodyweight for each degree of varus perturbation. Shifting the medial contact point medially increased medial loads and decreased lateral loads by between 1% and 4% bodyweight per millimeter. This study demonstrates that realistic measurement errors of 5mm (contact distance) or 5° (frontal plane alignment) could result in a combined 50% BW error in subject specific contact force estimates. We also show that model sensitivity varies between subjects as a result of differences in gait dynamics. These results demonstrate that predicted knee joint contact forces should be considered as a range of possible values determined by model uncertainty. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Medial Malleolar "Fleck Sign" May Predict Ankle Instability in Ligamentous Supination External Rotation Ankle Fractures.

PubMed

Nwosu, Kenneth; Schneiderman, Brian Andrew; Shymon, Stephen Joseph; Harris, Thomas

2018-06-01

Ankle joint stability dictates treatment in ligamentous supination external rotation ankle injuries (LSERAI). Investigation of the medial structures that support the ankle mortise is critical, and a small avulsion fracture, or "fleck", of the medial malleolus is occasionally encountered. This study aimed to assess the utility of this medial malleolus fleck sign (MMFS) in diagnosing instability requiring surgery in LSERAI. This retrospective observational study examined 166 LSERAI at a single level I trauma center. A standardized diagnostic and treatment protocol for ankle fractures was followed. LSERAI at presentation were reported as having a normal, dynamically wide, or statically wide medial clear space. Patient demographics, MMFS characteristics, and the use of operative management were recorded. MMFS incidence in the cohort was 16 (10%) of 166 and was present in 25% of patients with unstable LSERAI. Fifteen (94%) of 16 patients with a MMFS were deemed to have an unstable LSERAI (P < .005). MMFS had a 25% sensitivity and 99% specificity in diagnosing an unstable LSERAI. For the subgroup of patients without a statically wide medial clear space, MMFS had a 50% sensitivity and 99% specificity in determining instability. A MMFS may be indicative of an unstable LSERAI. With previous MRI studies demonstrating complete deltoid disruption in unstable LSERAI, we deduce the MMFS may be associated with extensive deltoid incompetence. The MMFS may help to diagnose a complete deltoid injury in LSERAI with a normal medial clear space, which could influence treatment and reduce patient morbidity, radiation exposure, and healthcare costs. Level III: Retrospective Cohort Study.

Periorbital epidermoid cyst in the medial canthus of three dogs.

PubMed

Davidson, H J; Blanchard, G L

1991-01-15

Periorbital epidermoid cyst in the medial canthus was identified ultrasonographically and confirmed histologically in 3 dogs. Surgical resection of the cysts, with reconstruction of the lacrimal canaliculi, was curative in all 3 cases.

Modification of endoscopic medial maxillectomy: a novel approach for inverted papilloma of the maxillary sinus.

PubMed

Ghosh, A; Pal, S; Srivastava, A; Saha, S

2015-02-01

To describe modification to endoscopic medial maxillectomy for treating extensive Krouse stage II or III inverted papilloma of the nasal and maxillary sinus. Ten patients with inverted papilloma arising from the nasoantral area underwent diagnostic nasal endoscopy, contrast-enhanced computed tomography scanning of the paranasal sinus and pre-operative biopsy of the nasal mass. They were all managed using endoscopic medial maxillectomy and followed up for seven months to three years without recurrence. Most patients were aged 41-60 years at presentation, and most were male. Presenting symptoms were nasal obstruction, mass in the nasal cavity and epistaxis. In each case, computed tomography imaging showed a mass involving the nasal cavity and maxillary sinus, with bony remodelling. The endoscopic medial maxillectomy approach was modified by making an incision in the pyriform aperture and removing part of the anterolateral wall of the maxilla bone en bloc. Modified endoscopic medial maxillectomy providing full access to the maxillary and ethmoid sinuses is described in detail. This effective, reproducible technique is associated with reduced operative time and morbidity.

Endoscopic surgical treatment of neurogenic tumor in pterygopalatine and infratemporal fossae via extended medial maxillectomy.

PubMed

Xu, Feng; Sun, Xicai; Hu, Li; Wang, Jingjing; Wang, Dehui; Pasic, Thomas R; Kern, Robert C

2011-02-01

The endoscopic extended medial maxillectomy approach for the management of lesions of the pterygopalatine and infratemporal fossa provides excellent exposure and results with good hemostasis and low morbidity. This approach is a viable alternative to the open approaches to these areas. To describe an endoscopic extended medial maxillectomy approach for the treatment of nonmalignant tumors in the pterygopalatine and infratemporal fossa. From January 2004 to June 2007, five patients who had tumors in the pterygopalatine fossa and/or infratemporal fossa, and underwent surgical resection of the tumors with the endoscopic extended medial maxillectomy approach, were reviewed regarding demographics, preoperative images, tumor cell type, surgical techniques, and outcomes. Five patients underwent the procedure mentioned above; three females and two males with a mean age of 38 and a range of 21-58 years. All patients had adequate exposure and total tumor resection with the endoscopic extended medial maxillectomy approach. None of the patients required an external approach for tumor extirpation. There were no major postoperative complications. No evidence of tumor recurrence was noted after follow-up for 12-78 months.

Is the posterior cruciate ligament necessary for medial pivot knee prostheses with regard to postoperative kinematics?

PubMed

Fang, Chao-Hua; Chang, Chia-Ming; Lai, Yu-Shu; Chen, Wen-Chuan; Song, Da-Yong; McClean, Colin J; Kao, Hao-Yuan; Qu, Tie-Bing; Cheng, Cheng-Kung

2015-11-01

Excellent clinical and kinematical performance is commonly reported after medial pivot knee arthroplasty. However, there is conflicting evidence as to whether the posterior cruciate ligament should be retained. This study simulated how the posterior cruciate ligament, post-cam mechanism and medial tibial insert morphology may affect postoperative kinematics. After the computational intact knee model was validated according to the motion of a normal knee, four TKA models were built based on a medial pivot prosthesis; PS type, modified PS type, CR type with PCL retained and CR type with PCL sacrificed. Anteroposterior translation and axial rotation of femoral condyles on the tibia during 0°-135° knee flexion were analyzed. There was no significant difference in kinematics between the intact knee model and reported data for a normal knee. In all TKA models, normal motion was almost fully restored, except for the CR type with PCL sacrificed. Sacrificing the PCL produced paradoxical anterior femoral translation and tibial external rotation during full flexion. Either the posterior cruciate ligament or post-cam mechanism is necessary for medial pivot prostheses to regain normal kinematics after total knee arthroplasty. The morphology of medial tibial insert was also shown to produce a small but noticeable effect on knee kinematics. V.

Contributions of Medial Temporal Lobe and Striatal Memory Systems to Learning and Retrieving Overlapping Spatial Memories

PubMed Central

Brown, Thackery I.; Stern, Chantal E.

2014-01-01

Many life experiences share information with other memories. In order to make decisions based on overlapping memories, we need to distinguish between experiences to determine the appropriate behavior for the current situation. Previous work suggests that the medial temporal lobe (MTL) and medial caudate interact to support the retrieval of overlapping navigational memories in different contexts. The present study used functional magnetic resonance imaging (fMRI) in humans to test the prediction that the MTL and medial caudate play complementary roles in learning novel mazes that cross paths with, and must be distinguished from, previously learned routes. During fMRI scanning, participants navigated virtual routes that were well learned from prior training while also learning new mazes. Critically, some routes learned during scanning shared hallways with those learned during pre-scan training. Overlap between mazes required participants to use contextual cues to select between alternative behaviors. Results demonstrated parahippocampal cortex activity specific for novel spatial cues that distinguish between overlapping routes. The hippocampus and medial caudate were active for learning overlapping spatial memories, and increased their activity for previously learned routes when they became context dependent. Our findings provide novel evidence that the MTL and medial caudate play complementary roles in the learning, updating, and execution of context-dependent navigational behaviors. PMID:23448868

Medial perirhinal cortex disambiguates confusable objects

PubMed Central

Tyler, Lorraine K.; Monsch, Andreas U.; Taylor, Kirsten I.

2012-01-01

Our brain disambiguates the objects in our cluttered visual world seemingly effortlessly, enabling us to understand their significance and to act appropriately. The role of anteromedial temporal structures in this process, particularly the perirhinal cortex, is highly controversial. In some accounts, the perirhinal cortex is necessary for differentiating between perceptually and semantically confusable objects. Other models claim that the perirhinal cortex neither disambiguates perceptually confusable objects nor plays a unique role in semantic processing. One major hurdle to resolving this central debate is the fact that brain damage in human patients typically encompasses large portions of the anteromedial temporal lobe, such that the identification of individual substructures and precise neuroanatomical locus of the functional impairments has been difficult. We tested these competing accounts in patients with Alzheimer’s disease with varying degrees of atrophy in anteromedial structures, including the perirhinal cortex. To assess the functional contribution of each anteromedial temporal region separately, we used a detailed region of interest approach. From each participant, we obtained magnetic resonance imaging scans and behavioural data from a picture naming task that contrasted naming performance with living and non-living things as a way of manipulating perceptual and semantic confusability; living things are more similar to one another than non-living things, which have more distinctive features. We manually traced neuroanatomical regions of interest on native-space cortical surface reconstructions to obtain mean thickness estimates for the lateral and medial perirhinal cortex and entorhinal cortex. Mean cortical thickness in each region of interest, and hippocampal volume, were submitted to regression analyses predicting naming performance. Importantly, atrophy of the medial perirhinal cortex, but not lateral perirhinal cortex, entorhinal cortex or

The KineSpring® Knee Implant System: an implantable joint-unloading prosthesis for treatment of medial knee osteoarthritis

PubMed Central

Clifford, Anton G; Gabriel, Stefan M; O’Connell, Mary; Lowe, David; Miller, Larry E; Block, Jon E

2013-01-01

Symptomatic medial compartment knee osteoarthritis (OA) is the leading cause of musculoskeletal pain and disability in adults. Therapies intended to unload the medial knee compartment have yielded unsatisfactory results due to low patient compliance with conservative treatments and high complication rates with surgical options. There is no widely available joint-unloading treatment for medial knee OA that offers clinically important symptom alleviation, low complication risk, and high patient acceptance. The KineSpring® Knee Implant System (Moximed, Inc, Hayward, CA, USA) is a first-of-its-kind, implantable, extra-articular, extra-capsular prosthesis intended to alleviate knee OA-related symptoms by reducing medial knee compartment loading while overcoming the limitations of traditional joint-unloading therapies. Preclinical and clinical studies have demonstrated excellent prosthesis durability, substantial reductions in medial compartment and total joint loads, and clinically important improvements in OA-related pain and function. The purpose of this report is to describe the KineSpring System, including implant characteristics, principles of operation, indications for use, patient selection criteria, surgical technique, postoperative care, preclinical testing, and clinical experience. The KineSpring System has potential to bridge the gap between ineffective conservative treatments and irreversible surgical interventions for medial compartment knee OA. PMID:23717052

Evaluation of the thickness of the medial ulnar collateral ligament in junior high and high school baseball players.

PubMed

Nagamoto, Hideaki; Yamamoto, Nobuyuki; Kurokawa, Daisuke; Takahashi, Hiroyuki; Muraki, Takayuki; Tanaka, Minoru; Koike, Yoichi; Sano, Hirotaka; Itoi, Eiji

2015-07-01

Thickening of the medial ulnar collateral ligament in the throwing arm of adult baseball players is a well-known phenomenon. However, onset of the thickening is unclear among young baseball players. The purpose of this study was to evaluate the thickness of the medial ulnar collateral ligament in junior high and high school baseball players. Seventy-one uninjured and asymptomatic junior high and high school baseball players were included in the study. Participants underwent physical examination after completing a questionnaire, followed by ultrasonographic evaluation. The thickness of the medial ulnar collateral ligament was measured bilaterally. The thickness of the throwing and non-throwing sides in high school and junior high school baseball players, and within each group, was compared and statistically analyzed. The medial ulnar collateral ligament in the throwing arm of high school baseball players was thicker than that in the non-throwing arm (5.5 vs. 4.4 mm), although no significant difference was seen in junior high school baseball players. High school baseball players showed a significantly thicker medial ulnar collateral ligament in the throwing arm than junior high school baseball players. Thickening of the medial ulnar collateral ligament in the throwing arm of asymptomatic and uninjured baseball players may begin by the time the players reach high school.

Efficacy of pulsed radiofrequency medial branch treatment in low back pain patients.

PubMed

Kim, Do Hyoung; Han, Seong Rok; Choi, Chan Young; Sohn, Moon Jun; Lee, Chae Heuck

2016-04-27

It was thought that the efficacy of pulsed radiofrequency (PRF) treatment of the medial branch in patients with lower back pain was not as long lasting as that of continuous radiofrequency (CRF) thermo-coagulation techniques. The goal of this study was to determine the efficacy and the long-term effects of PRF treatment of the medial branch in selected low back pain patients. We retrospectively reviewed and analyzed patients with lower back pain who underwent PRF treatment on the medial branch at our institute. Pain relief was evaluated by visual analog scale (VAS) score at pretreatment, 2 weeks, 6 months, 1 year and 2 years post-treatment. Oswestry disability index (ODI) score was evaluated pretreatment and at 2 years post-treatment. We also recorded the satisfaction period after PRF treatment. Twenty-three patients were available for the 2-year follow-up analysis. None of the patients had any side effects or procedure-related complications during the follow up period. The average VAS score declined from 7.1 ± 2.4 pre-treatment to 2.9 ± 2.1 2 weeks post-treatment, 2.6 ± 1.8 at 6 months, 2.8 ± 2.1 at 1 year and 3.0 ± 2.5 at 2 years. The average ODI score decreased from 33.6 ± 13.6 pre-treatment to 15.3 ± 5.7 at 2 years post-treatment. Mean satisfaction period after PRF treatment was 16.6 ± 9.43 months. PRF treatment on the medial branch is an effective and safe treatment option for patients with lower back pain.

Medial meniscus extrusion correlates with disease duration of the sudden symptomatic medial meniscus posterior root tear.

PubMed

Furumatsu, T; Kamatsuki, Y; Fujii, M; Kodama, Y; Okazaki, Y; Masuda, S; Ozaki, T

2017-12-01

Medial meniscus posterior root tear (MMPRT) leads to abnormal biomechanics of the knee by inducing the medial meniscus extrusion (MME). However, a time-dependent increase of the MME is not fully elucidated in patients suffering from the acute MMPRT. The aim of this study was to investigate the relationships among disease duration of the MMPRT and severity of the MME. We hypothesized that MME measurement correlates with disease duration after a sudden onset of the minor traumatic MMPRT during the short-term follow-up period. Forty-six patients who had an accurate episode of the posteromedial painful popping were investigated. All the patients were diagnosed having a symptomatic MMPRT with magnetic resonance imaging (MRI) examinations. Absolute MME was measured using MRI scans within 12 months after painful popping events. A correlation coefficient between duration from injury to MRI examination and absolute MME was evaluated. Mean absolute MME was 4.5±1.6mm (range, 1.1-8.8mm) on MRI measurements. A good correlation was observed between MME measurement and duration from injury to MRI examination (R 2 =0.612). The best-fit equation for predicting each value was: MME=0.014×disease duration+3.288mm. This study demonstrated that absolute MME increases progressively within the short duration after the onset of symptomatic MMPRT. Our results suggest that preoperative MME assessment may be important in determining disease duration and treatment strategy of the MMPRT. Retrospective cohort study level IV. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

SPECT (HMPAO) support for activation of the medial prefrontal cortices during toe graphaesthesia.

PubMed

Persinger, M A; Webster, D; Tiller, S G

1998-08-01

This experiment was designed to test the construct validity of psychometric analyses that suggested a strong functional association between the accuracy for toe graphaesthesia and selective activation of neurons within the medial prefrontal regions. Single Photon Emission Computerized Tomography (SPECT) profiles were obtained for three volunteers (2 men, 1 woman) after they had been exposed to a toe graphaesthesia task or had been exposed to the control setting. The two measurements for each participant were separated by at least one week. Qualitative evaluation, using criteria employed for clinical diagnoses, of serial coronal, sagittal, and horizontal sections clearly indicated a specific increase in uptake of tracer within the rostral one-third to one-half of the medial prefrontal cortices of all three subjects during the toe graphaesthesia task compared to that during baseline conditions. The results are consistent with our neuropsychological research which indicates that toe graphaesthesia may be an accurate and useful indicator of the functional integrity of the medial surfaces of the anterior cerebral hemispheres.

Transosseous-equivalent rotator cuff repair: a systematic review on the biomechanical importance of tying the medial row.

PubMed

Mall, Nathan A; Lee, Andrew S; Chahal, Jaskarndip; Van Thiel, Geoffrey S; Romeo, Anthony A; Verma, Nikhil N; Cole, Brian J

2013-02-01

Double-row and transosseous-equivalent repair techniques have shown greater strength and improved healing than single-row techniques. The purpose of this study was to determine whether tying of the medial-row sutures provides added stability during biomechanical testing of a transosseous-equivalent rotator cuff repair. We performed a systematic review of studies directly comparing biomechanical differences. Five studies met the inclusion and exclusion criteria. Of the 5 studies, 4 showed improved biomechanical properties with tying the medial-row anchors before bringing the sutures laterally to the lateral-row anchors, whereas the remaining study showed no difference in contact pressure, mean failure load, or gap formation with a standard suture bridge with knots tied at the medial row compared with knotless repairs. The results of this systematic review and quantitative synthesis indicate that the biomechanical factors ultimate load, stiffness, gap formation, and contact area are significantly improved when medial knots are tied as part of a transosseous-equivalent suture bridge construct compared with knotless constructs. Further studies comparing the clinical healing rates and functional outcomes between medial knotted and knotless repair techniques are needed. This review indicates that biomechanical factors are improved when the medial row of a transosseous-equivalent rotator cuff is tied compared with a knotless repair. However, this has not been definitively proven to translate to improved healing rates clinically. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Osteoligamentous injuries of the medial ankle joint.

PubMed

Lötscher, P; Lang, T H; Zwicky, L; Hintermann, B; Knupp, M

2015-12-01

Injuries of the ankle joint have a high incidence in daily life and sports, thus, playing an important socioeconomic role. Therefore, proper diagnosis and adequate treatment are mandatory. While most of the ligament injuries around the ankle joint are treated conservatively, great controversy exists on how to treat deltoid ligament injuries in ankle fractures. Missed injuries and inadequate treatment of the medial ankle lead to inferior outcome with instability, progressive deformity, and ankle joint osteoarthritis.

Matrix Metalloproteases and Tissue Inhibitors of Metalloproteinases in Medial Plica and Pannus-like Tissue Contribute to Knee Osteoarthritis Progression

PubMed Central

Yang, Chih-Chang; Lin, Cheng-Yu; Wang, Hwai-Shi; Lyu, Shaw-Ruey

2013-01-01

Osteoarthritis (OA) is characterized by degradation of the cartilage matrix, leading to pathologic changes in the joints. However, the pathogenic effects of synovial tissue inflammation on OA knees are not clear. To investigate whether the inflammation caused by the medial plica is involved in the pathogenesis of osteoarthritis, we examined the expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), interleukin (IL)-1β, and tumor necrosis factor (TNF)-α in the medial plica and pannus-like tissue in the knees of patients with medial compartment OA who underwent either arthroscopic medial release (stage II; 15 knee joints from 15 patients) or total knee replacement (stage IV; 18 knee joints from 18 patients). MMP-2, MMP-3, MMP-9, IL-1β, and TNF-α mRNA and protein levels measured, respectively, by quantitative real-time PCR and Quantibody human MMP arrays, were highly expressed in extracts of medial plica and pannus-like tissue from stage IV knee joints. Immunohistochemical staining also demonstrated high expression of MMP-2, MMP-3, and MMP-9 in plica and pannus-like tissue of stage IV OA knees and not in normal cartilage. Some TIMP/MMP ratios decreased significantly in both medial plica and pannus-like tissue as disease progressed from stage II to stage IV. Furthermore, the migration of cells from the pannus-like tissue was enhanced by IL-1β, while plica cell migration was enhanced by TNF-α. The results suggest that medial plica and pannus-like tissue may be involved in the process of cartilage degradation in medial compartment OA of the knee. PMID:24223987

Matrix metalloproteases and tissue inhibitors of metalloproteinases in medial plica and pannus-like tissue contribute to knee osteoarthritis progression.

PubMed

Yang, Chih-Chang; Lin, Cheng-Yu; Wang, Hwai-Shi; Lyu, Shaw-Ruey

2013-01-01

Osteoarthritis (OA) is characterized by degradation of the cartilage matrix, leading to pathologic changes in the joints. However, the pathogenic effects of synovial tissue inflammation on OA knees are not clear. To investigate whether the inflammation caused by the medial plica is involved in the pathogenesis of osteoarthritis, we examined the expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), interleukin (IL)-1β, and tumor necrosis factor (TNF)-α in the medial plica and pannus-like tissue in the knees of patients with medial compartment OA who underwent either arthroscopic medial release (stage II; 15 knee joints from 15 patients) or total knee replacement (stage IV; 18 knee joints from 18 patients). MMP-2, MMP-3, MMP-9, IL-1β, and TNF-α mRNA and protein levels measured, respectively, by quantitative real-time PCR and Quantibody human MMP arrays, were highly expressed in extracts of medial plica and pannus-like tissue from stage IV knee joints. Immunohistochemical staining also demonstrated high expression of MMP-2, MMP-3, and MMP-9 in plica and pannus-like tissue of stage IV OA knees and not in normal cartilage. Some TIMP/MMP ratios decreased significantly in both medial plica and pannus-like tissue as disease progressed from stage II to stage IV. Furthermore, the migration of cells from the pannus-like tissue was enhanced by IL-1β, while plica cell migration was enhanced by TNF-α. The results suggest that medial plica and pannus-like tissue may be involved in the process of cartilage degradation in medial compartment OA of the knee.

Taiwanese life scientists less "medialized" than their Western colleagues.

PubMed

Lo, Yin-Yueh; Peters, Hans Peter

2015-01-01

The article presents results from surveys of life scientists in Taiwan (n=270) and in Germany (n=326). Fewer Taiwanese than German researchers have frequent contact with the media and they rate their experiences with journalists less positively. Furthermore, they are less prepared to adapt to journalistic expectations and to a greater extent than German researchers they expect journalists to consider scientific criteria in their reporting. These findings are interpreted in Weingart's "medialization of science" framework as indicators of lower medialization of science in Taiwan than in Germany. However, Taiwanese scientists are more willing than German scientists to accept journalistic simplification at the expense of accuracy. This is explained as an adaptation to the media system and to the perceived scientific literacy of the media audience. We hypothesize that cultural differences regarding the relative priority of relational vs. rational communication goals may also contribute to more tolerance of journalistic simplification in Taiwan. © The Author(s) 2013.

REHABILITATION FOLLOWING MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION FOR PATELLAR INSTABILITY

PubMed Central

Prohaska, Daniel

2017-01-01

Patellar instability is a common problem seen by physical therapists, athletic trainers and orthopedic surgeons. Although following an acute dislocation, conservative rehabilitation is usually the first line of defense; refractory cases exist that may require surgical intervention. Substantial progress has been made in the understanding of the medial patellofemoral ligament (MPFL) and its role as the primary stabilizer to lateral patellar displacement. Medial patellofemoral ligament disruption is now considered to be the essential lesion following acute patellar dislocation due to significantly high numbers of ruptures following this injury. Evidence is now mounting that demonstrates the benefits of early reconstruction with a variety of techniques. Recently rehabilitation has become more robust and progressive due to our better understanding of soft tissue reconstruction and repair techniques. The purpose of this manuscript is to describe the etiology of patellar instability, the anatomy and biomechanics and examination of patellofemoral instability, and to describe surgical intervention and rehabilitation following MPFL rupture. Level of Evidence 5 PMID:28593102

Loading of the medial meniscus in the ACL deficient knee: A multibody computational study.

PubMed

Guess, Trent M; Razu, Swithin

2017-03-01

The menisci of the knee reduce tibiofemoral contact pressures and aid in knee lubrication and nourishment. Meniscal injury occurs in half of knees sustaining anterior cruciate ligament injury and the vast majority of tears in the medial meniscus transpire in the posterior horn region. In this study, computational multibody models of the knee were derived from medical images and passive leg motion for two female subjects. The models were validated against experimental measures available in the literature and then used to evaluate medial meniscus contact force and internal hoop tension. The models predicted that the loss of anterior cruciate ligament (ACL) constraint increased contact and hoop forces in the medial menisci by a factor of 4 when a 100N anterior tibial force was applied. Contact forces were concentrated in the posterior horn and hoop forces were also greater in this region. No differences were found in contact or hoop tension between the intact and ACL deficient (ACLd) knees when only a 5Nm external tibial torque was applied about the long axis of the tibia. Combining a 100N anterior tibial force and a 5Nm external tibial torque increased posterior horn contact and hoop forces, even in the intact knee. The results of this study show that the posterior horn region of the medial meniscus experiences higher contact forces and hoop tension, making this region more susceptible to injury, especially with the loss of anterior tibia motion constraint provided by the ACL. The contribution of the dMCL in constraining posterior medial meniscus motion, at the cost of higher posterior horn hoop tension, is also demonstrated. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Loading of the Medial Meniscus in the ACL deficient knee: a Multibody Computational Study

PubMed Central

Razu, Swithin

2017-01-01

The menisci of the knee reduce tibiofemoral contact pressures and aid in knee lubrication and nourishment. Meniscal injury occurs in half of knees sustaining anterior cruciate ligament injury and the vast majority of tears in the medial meniscus transpire in the posterior horn region. In this study, computational multibody models of the knee were derived from medical images and passive leg motion for two female subjects. The models were validated against experimental measures available in the literature and then used to evaluate medial meniscus contact force and internal hoop tension. The models predicted that the loss of anterior cruciate ligament (ACL) constraint increased contact and hoop forces in the medial menisci by a factor of 4 when a 100 N anterior tibial force was applied. Contact forces were concentrated in the posterior horn and hoop forces were also greater in this region. No differences were found in contact or hoop tension between the intact and ACL deficient (ACLd) knees when only a 5 Nm external tibial torque was applied about the long axis of the tibia. Combining a 100 N anterior tibial force and a 5 Nm external tibial torque increased posterior horn contact and hoop forces, even in the intact knee. The results of this study show that the posterior horn region of the medial meniscus experiences higher contact forces and hoop tension, making this region more susceptible to injury, especially with the loss of anterior tibia motion constraint provided by the ACL. The contribution of the dMCL in constraining posterior medial meniscus motion, at the cost of higher posterior horn hoop tension, is also demonstrated. PMID:28089224

Medial shoe-ground pressure and specific running injuries: A 1-year prospective cohort study.

PubMed

Brund, René B K; Rasmussen, Sten; Nielsen, Rasmus O; Kersting, Uwe G; Laessoe, Uffe; Voigt, Michael

2017-09-01

Achilles tendinitis, plantar fasciopathy and medial tibial stress syndrome injuries (APM-injuries) account for approximately 25% of the total number of running injuries amongst recreational runners. Reports on the association between static foot pronation and APM-injuries are contradictory. Possibly, dynamic measures of pronation may display a stronger relationship with the risk of APM-injuries. Therefore, the purpose of the present study was to investigate if running distance until the first APM-injury was dependent on the foot balance during stance phase in recreational male runners. Prospective cohort study. Foot balance for both feet was measured during treadmill running at the fastest possible 5000-m running pace in 79 healthy recreational male runners. Foot balance was calculated by dividing the average of medial pressure with the average of lateral pressure. Foot balance was categorized into those which presented a higher lateral shod pressure (LP) than medial pressure, and those which presented a higher medial shod pressure (MP) than lateral pressure during the stance phase. A time-to-event model was used to compare differences in incidence between foot balance groups. Compared with the LP-group (n=59), the proportion of APM-injuries was greater in the MP-group (n=99) after 1500km of running, resulting in a cumulative risk difference of 16%-points (95% CI=3%-point; 28%-point, p=0.011). Runners displaying a more medial pressure during stance phase at baseline sustained a greater amount of APM-injuries compared to those displaying a lateral shod pressure during stance phase. Prospective studies including a greater amount of runners are needed to confirm this relationship. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Experimental many-pairs nonlocality

NASA Astrophysics Data System (ADS)

Poh, Hou Shun; Cerè, Alessandro; Bancal, Jean-Daniel; Cai, Yu; Sangouard, Nicolas; Scarani, Valerio; Kurtsiefer, Christian

2017-08-01

Collective measurements on large quantum systems together with a majority voting strategy can lead to a violation of the Clauser-Horne-Shimony-Holt Bell inequality. In the presence of many entangled pairs, this violation decreases quickly with the number of pairs and vanishes for some critical pair number that is a function of the noise present in the system. Here we show that a different binning strategy can lead to a more substantial Bell violation when the noise is sufficiently small. Given the relation between the critical pair number and the source noise, we then present an experiment where the critical pair number is used to quantify the quality of a high visibility photon pair source. Our results demonstrate nonlocal correlations using collective measurements operating on clusters of more than 40 photon pairs.

Tibiofemoral contact mechanics following posterior root of medial meniscus tear, repair, meniscectomy, and allograft transplantation.

PubMed

Kim, Jin Goo; Lee, Yong Seuk; Bae, Tae Soo; Ha, Jeong Ku; Lee, Dong Hoon; Kim, Young Jae; Ra, Ho Jong

2013-09-01

The purposes of this study were to evaluate the effect on tibiofemoral contact mechanics of repair of the posterior root of the medial meniscus and the effect of meniscal allograft transplantation (MAT) with medial collateral ligament (MCL) release at different flexion angles. Ten fresh-frozen human cadaveric knees (five pairs) were used. A digital pressure sensor was inserted by capsulotomy, and experiments were performed serially under the following six conditions, that is, with an intact medial meniscus (normal controls), with a root tear, after root repair, after total meniscectomy, after MAT, and after MAT plus MCL release. During each experiment, knees were positioned at 0°, 30°, 60°, and 90° of flexion, and peak pressure (kPa) and contact area (cm2) were measured. At 0° of flexion, contact pressure did not differ among the six experimental settings. However, at 30° and 60° of flexion, contact pressure differed significantly between root tear and root repair specimens (p = 0.04 and 0.03, respectively), and between total meniscectomy and MAT specimens (p = 0.02 and 0.03, respectively). On the other hand, mean contact pressures were different between normal (476.7 ± 473.1 and 573.3 ± 479.1 kPa) and root repair (575.7 ± 357.8 and 598.6 ± 415.8), and between normal and MAT (635.7 ± 437.4 and 674.3 ± 533.2). At 0°, 30°, 60°, and 90° of flexion, contact areas differed significantly between normal and total meniscectomy specimens (p = 0.02, 0.01, 0.02, and 0.02, respectively), and between MAT and total meniscectomy specimens (p = 0.03, 0.02, 0.02, and 0.03, respectively). Contact areas differed significantly between root tear and root repair specimens at 60° of flexion (p = 0.04), and between normal control and root repair specimens at 60° and 90° of flexion (p = 0.03 and 0.04, respectively). The effects of MAT plus MCL release on contact mechanics were not different from the effects of MAT alone (n.s.). Both meniscal root repair and

Meniscal Extrusion Progresses Shortly after the Medial Meniscus Posterior Root Tear.

PubMed

Furumatsu, Takayuki; Kodama, Yuya; Kamatsuki, Yusuke; Hino, Tomohito; Okazaki, Yoshiki; Ozaki, Toshifumi

2017-12-01

Medial meniscus posterior root tears (MMPRT) induce medial meniscus extrusion (MME). However, the time-dependent extent of MME in patients suffering from the MMPRT remains unclear. This study evaluated the extent of MME after painful popping events that occurred at the onset of the MMPRT. Thirty-five patients who had an episode of posteromedial painful popping were investigated. All the patients were diagnosed as having an MMPRT by magnetic resonance imaging (MRI) within 12 months after painful popping. Medial meniscus body width (MMBW), absolute MME, and relative MME (100×absolute MME/MMBW) were assessed among three groups divided according to the time after painful popping events: early period (〈1 month), subacute period (1-3 months), and chronic period (4-12 months). In the early period, absolute and relative MMEs were 3.0 mm and 32.7%, respectively. Absolute MME increased up to 4.2 mm and 5.8 mm during the subacute and chronic periods, respectively. Relative MME also progressed to 49.2% and 60.3% in the subacute and chronic periods, respectively. This study demonstrated that absolute and relative MMEs increased progressively within the short period after the onset of symptomatic MMPRT. Our results suggest that early diagnosis of an MMPRT may be important to prevent progression of MME following the MMPRT.

Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition.

PubMed

Nelson, A J D; Thur, K E; Horsley, R R; Spicer, C; Marsden, C A; Cassaday, H J

2011-03-01

Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine (DA) function but the locus within the nucleus accumbens of this effect is as yet not firmly established. Experiment 1 tested whether 6-hydroxydopamine (6-OHDA)-induced lesions of DA terminals within the core and medial shell subregions of the nucleus accumbens (NAc) would enhance LI under conditions that normally disrupt LI in controls (weak pre-exposure). LI was measured in a thirst motivated conditioned emotional response procedure with 10 pre-exposures (to a noise CS) and 2 conditioning trials. The vehicle-injected and core-lesioned animals did not show LI and conditioned to the pre-exposed CS at comparable levels to the non-pre-exposed controls. 6-OHDA lesions to the medial shell, however, produced potentiation of LI, demonstrated across two extinction tests. In a subsequent experiment, haloperidol microinjected into the medial shell prior to conditioning similarly enhanced LI. These results underscore the dissociable roles of core and shell subregions of the NAc in mediating the expression of LI and indicate that reduced DA function within the medial shell leads to enhanced LI. Copyright © 2010 Elsevier Inc. All rights reserved.

Medial temporal lobe atrophy relates more strongly to sleep-wake rhythm fragmentation than to age or any other known risk.

PubMed

Van Someren, Eus J W; Oosterman, J M; Van Harten, B; Vogels, R L; Gouw, A A; Weinstein, H C; Poggesi, A; Scheltens, Ph; Scherder, E J A

2018-06-01

Atrophy of the medial temporal lobe of the brain is key to memory function and memory complaints in old age. While age and some morbidities are major risk factors for medial temporal lobe atrophy, individual differences remain, and mechanisms are insufficiently known. The largest combined neuroimaging and whole genome study to date indicates that medial temporal lobe volume is most associated with common polymorphisms in the GRIN2B gene that encodes for the 2B subunit (NR2B) of the NMDA receptor. Because sleep disruption induces a selective loss of NR2B from hippocampal synaptic membranes in rodents, and because of several other reports on medial temporal lobe sensitivity to sleep disruption, we hypothesized a contribution of the typical age-related increase in sleep-wake rhythm fragmentation to medial temporal lobe atrophy. Magnetic resonance imaging and actigraphy in 138 aged individuals showed that individual differences in sleep-wake rhythm fragmentation accounted for more (19%) of the variance in medial temporal lobe atrophy than age did (15%), or any of a list of health and brain structural indicators. The findings suggest a role of sleep-wake rhythm fragmentation in age-related medial temporal lobe atrophy, that might in part be prevented or reversible. Copyright © 2018. Published by Elsevier Inc.

Knee medial and lateral contact forces in a musculoskeletal model with subject-specific contact point trajectories.

PubMed

Zeighami, A; Aissaoui, R; Dumas, R

2018-03-01

Contact point (CP) trajectory is a crucial parameter in estimating medial/lateral tibio-femoral contact forces from the musculoskeletal (MSK) models. The objective of the present study was to develop a method to incorporate the subject-specific CP trajectories into the MSK model. Ten healthy subjects performed 45 s treadmill gait trials. The subject-specific CP trajectories were constructed on the tibia and femur as a function of extension-flexion using low-dose bi-plane X-ray images during a quasi-static squat. At each extension-flexion position, the tibia and femur CPs were superimposed in the three directions on the medial side, and in the anterior-posterior and proximal-distal directions on the lateral side to form the five kinematic constraints of the knee joint. The Lagrange multipliers associated to these constraints directly yielded the medial/lateral contact forces. The results from the personalized CP trajectory model were compared against the linear CP trajectory and sphere-on-plane CP trajectory models which were adapted from the commonly used MSK models. Changing the CP trajectory had a remarkable impact on the knee kinematics and changed the medial and lateral contact forces by 1.03 BW and 0.65 BW respectively, in certain subjects. The direction and magnitude of the medial/lateral contact force were highly variable among the subjects and the medial-lateral shift of the CPs alone could not determine the increase/decrease pattern of the contact forces. The suggested kinematic constraints are adaptable to the CP trajectories derived from a variety of joint models and those experimentally measured from the 3D imaging techniques. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mechanism of the Rapid Effect of 17β -Estradiol on Medial Amygdala Neurons

NASA Astrophysics Data System (ADS)

Nabekura, Junichi; Oomura, Yutaka; Minami, Taketsugu; Mizuno, Yuji; Fukuda, Atsuo

1986-07-01

The mechanism by which sex steroids rapidly modulate the excitability of neurons was investigated by intracellular recording of neurons in rat medial amygdala brain slices. Brief hyperpolarization and increased potassium conductance were produced by 17β - estradiol. This effect persisted after elimination of synaptic input and after suppression of protein synthesis. Thus, 17β -estradiol directly changes the ionic conductance of the postsynaptic membrane of medial amygdala neurons. In addition, a greater proportion of the neurons from females than from males responded to 17β -estradiol.

A unified framework for the functional organization of the medial temporal lobes and the phenomenology of episodic memory.

PubMed

Ranganath, Charan

2010-11-01

There is currently an intense debate about the nature of recognition memory and about the roles of medial temporal lobe subregions in recognition memory processes. At a larger level, this debate has been about whether it is appropriate to propose unified theories to explain memory at neural, functional, and phenomenological levels of analysis. Here, I review findings from physiology, functional imaging, and lesion studies in humans, monkeys, and rodents relevant to the roles of medial temporal lobe subregions in recognition memory, as well as in short-term memory and perception. The results from these studies are consistent with the idea that there is functional heterogeneity in the medial temporal lobes, although the differences among medial temporal lobe subregions do not precisely correspond to different types of memory tasks, cognitive processes, or states of awareness. Instead, the evidence is consistent with the idea that medial temporal lobe subregions differ in terms of the kind of information they process and represent, and that these regions collectively support episodic memory by binding item and context information. © 2010 Wiley-Liss, Inc.

"TuNa-saving" endoscopic medial maxillectomy: a surgical technique for maxillary inverted papilloma.

PubMed

Pagella, Fabio; Pusateri, Alessandro; Matti, Elina; Avato, Irene; Zaccari, Dario; Emanuelli, Enzo; Volo, Tiziana; Cazzador, Diego; Citraro, Leonardo; Ricci, Giampiero; Tomacelli, Giovanni Leo

2017-07-01

The maxillary sinus is the most common site of sinonasal inverted papilloma. Endoscopic sinus surgery, in particular endoscopic medial maxillectomy, is currently the gold standard for treatment of maxillary sinus papilloma. Although a common technique, complications such as stenosis of the lacrimal pathway and consequent development of epiphora are still possible. To avoid these problems, we propose a modification of this surgical technique that preserves the head of the inferior turbinate and the nasolacrimal duct. A retrospective analysis was performed on patients treated for maxillary inverted papilloma in three tertiary medical centres between 2006 and 2014. Pedicle-oriented endoscopic surgery principles were applied and, in select cases where the tumour pedicle was located on the anterior wall, a modified endoscopic medial maxillectomy was carried out as described in this paper. From 2006 to 2014 a total of 84 patients were treated. A standard endoscopic medial maxillectomy was performed in 55 patients (65.4%), while the remaining 29 (34.6%) had a modified technique performed. Three recurrences (3/84; 3.6%) were observed after a minimum follow-up of 24 months. A new surgical approach for select cases of maxillary sinus inverted papilloma is proposed in this paper. In this technique, the endoscopic medial maxillectomy was performed while preserving the head of the inferior turbinate and the nasolacrimal duct ("TuNa-saving"). This technique allowed for good visualization of the maxillary sinus, good oncological control and a reduction in the rate of complications.

[Medial patellofemoral ligament reconstruction using quadriceps tendon].

PubMed

Lenschow, S; Herbort, M; Fink, C

2015-12-01

Stabilization of the patella by medial patellofemoral ligament (MPFL) reconstruction. Recurrent lateral patella instability with chronic weakening of the MPFL. Femoropatellar cartilage defects ICRS grade 3° or higher. Tuberositas Tibiae Trochlear Groove Index (TTTG) >20 mm. Lateral hypercompression of the patella without instability. A 3 cm transverse skin incision at the superomedial edge of the patella in 90° of flexion. Longitudinal incision of the prepatellar bursa and exposure of the quadriceps tendon. Preparation of a flat tendon strip with a length of 8 cm, a width of 10 mm, and a thickness of 3 mm, leaving the attachment at the patella intact. Flipping of the tendon strip and passing of the graft through a tunnel underneath the prepatellar tissue at the medial edge of the patella. Passing of the graft in layer two of the medial joint capsule just below the fascia (layer 1) and the vastus medialis. Fixation of the graft in a bone tunnel, drilled in the femoral insertion site of the native MPFL using a biodegradable interference screw. Patella centralizing brace for 4 weeks with range of motion (ROM) 0/0/90°, 20 kg of partial weight bearing for 3 weeks. Full weight-bearing according to pain starting from week 4 postoperatively. ROM up to 90° of flexion directly postoperatively. Free ROM starting from week 6 postoperatively. Stationary cycling 6 weeks postoperatively. Swimming and running after 10 months. Return to pivoting sports after 4-5 months. A total of 17 patients (7 men and 10 women; average age 21.5 years ±3.9 years, average BMI 22.6 ±3.9) were treated using this technique between March 2011 and November 2012. Only patients with at least one recurrent patella dislocation following conservative treatment were included. Patient satisfaction 12 months postoperatively was very high. Overall, 94.1 % would undergo the procedure again and 94.1 % were very satisfied with the cosmetic result. Significant improvement in Lysholm score 6, 12, and 24

Improvement in the medial meniscus posterior shift following anterior cruciate ligament reconstruction.

PubMed

Inoue, Hiroto; Furumatsu, Takayuki; Miyazawa, Shinichi; Fujii, Masataka; Kodama, Yuya; Ozaki, Toshifumi

2018-02-01

Anterior cruciate ligament (ACL) reconstruction can reduce the risk of developing osteoarthritic knees. The goals of ACL reconstruction are to restore knee stability and reduce post-traumatic meniscal tears and cartilage degradation. A chronic ACL insufficiency frequently results in medial meniscus (MM) injury at the posterior segment. How ACL reconstruction can reduce the deformation of the MM posterior segment remains unclear. In this study, we evaluated the form of the MM posterior segment and anterior tibial translation before and after ACL reconstruction using open magnetic resonance imaging (MRI). Seventeen patients who underwent ACL reconstructions without MM injuries were included in this study. MM deformation was evaluated using open MRI before surgery and 3 months after surgery. We measured medial meniscal length (MML), medial meniscal height (MMH), medial meniscal posterior body width (MPBW), MM-femoral condyle contact width (M-FCW) and posterior tibiofemoral distance (PTFD) at knee flexion angles of 10° and 90°. There were no significant pre- and postoperative differences during a flexion angle of 10°. At a flexion angle of 90°, MML decreased from 43.7 ± 4.5 to 41.4 ± 4.5 mm (P < 0.001), MMH from 7.5 ± 1.4 to 6.9 ± 1.4 mm (P = 0.006), MPBW from 13.1 ± 2.0 to 12.2 ± 1.9 mm (P < 0.001) and M-FCW from 10.0 ± 1.5 to 8.5 ± 1.5 mm (P < 0.001) after ACL reconstruction. The PTFD increased from 2.1 ± 2.8 to 2.7 ± 2.4 mm after ACL reconstruction (P = 0.015). ACL reconstruction affects the contact pattern between the MM posterior segment and medial femoral condyle and can reduce the deformation of the MM posterior segment in the knee-flexed position by reducing abnormal anterior tibial translation. It possibly prevents secondary injury to the MM posterior segment and cartilage that progresses to knee osteoarthritis. IV.

Posterior root tear of the medial meniscus in multiple knee ligament injuries.

PubMed

Kim, Young Jae; Kim, Jin Goo; Chang, Seok Hwan; Shim, Jae Chan; Kim, Sang Bum; Lee, Mi Young

2010-10-01

The purposes of the present study were to examine the frequency and characteristics of root tears of the medial meniscus associated with ligament injuries of the knee and to evaluate the effectiveness of pull-out repair for restoring meniscus function. We retrospectively analyzed the 9 patients (10 knees) with posterior root tears of the medial meniscus and ligament injuries of the knee treated between August 2004 and February 2007. All the patients were male, with average age of 29.8 years, and the mean follow-up period was 29.7 months. The pull-out suture technique was used to repair the root tears. Clinical outcomes were evaluated using the Lysholm, IKDC, and Tegner scores, as well as the McMurray and Apley tests. The mean follow-up period was 41.1 months (range, 30 to 63 months). The incidence of root tears of the medial meniscus with ligament injuries was 2.74% (10 cases in 365 ligament surgeries). All clinical results showed significant improvement. At the final follow-up, McMurray test showed one positive and nine negative cases, and the Apley test revealed two positive and eight negative cases. There were no positive findings in anterior drawer test, posterior drawer test, valgus and varus stress test, and posterolateral instability test. Healing of the root tear was confirmed by arthroscopy in five patients and by MR in four patients. Root tears of the medial meniscus may occur in multiple knee ligament injuries. It is important not to miss them. Our results indicate that pull-out repair provides satisfactory results and evidence of healing. Copyright 2009 Elsevier B.V. All rights reserved.

Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

PubMed

Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

2018-04-01

Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137). Medial elbow joint space increases under a valgus load and then

BIOCHEMISTRY OF THE ANTERIOR, MEDIAL, AND POSTERIOR GENIOGLOSSUS IN THE AGED RAT

PubMed Central

Schaser, Allison J.; Wang, Hao; Volz, Lana M.; Connor, Nadine P.

2010-01-01

Age-related tongue weakness may contribute to swallowing deficits in the elderly. One contributing factor may be an alteration in muscle fiber type properties with aging. However, it is not clear how muscle fiber types within the aged tongue may vary from those found in young adults, or how fiber types may vary across the anteroposterior axis of the extrinsic tongue muscles. We examined myosin heavy chain (MHC) composition of anterior, medial, and posterior sections of the genioglossus muscle (GG) in 10 old male Fischer 344/Brown Norway rats and compared findings to previously reported data from young adult male rats. Significant differences (p< .01) between young adult and old rats were found in the distribution of MHC isoforms along the anteroposterior axis of the muscle. In the anterior, medial, and posterior regions, there was a significantly smaller proportion of type IIb MHC in the old rat GG muscles, while the proportion of type IIx MHC was significantly greater. In the medial region, the proportion of type I MHC was found to be significantly greater in the old rats. Thus, we found a shift to more slowly contracting muscle fibers in the aged rat tongue. PMID:20809174

Autoshaping a leverpress in rats with lateral, medial, or complete septal lesions.

PubMed

Poplawsky, A; Phillips, C L

1986-05-01

Rats with either control operations or lateral, medial, or complete septal lesions received 600 trials of leverpress training using an autoshaping procedure, i.e., food delivery followed a 10 s illuminated lever presentation, or occurred immediately after a leverpress. Rats with complete septal lesions acquired the leverpress faster than controls and had more food-tray entries per minute during the first 100 trials than the other groups. Rats with lateral or medial septal lesions had leverpress and food-tray entries equivalent to controls. The facilitation of autoshaping a leverpress may partially be explained by the general increase in motor reactivity to stimuli found following septal lesions.

Medial-to-lateral Ratio of Tibiofemoral Subchondral Bone Area is Adapted to Alignment and Mechanical Load

PubMed Central

Eckstein, Felix; Hudelmaier, Martin; Cahue, September; Marshall, Meredith; Sharma, Leena

2010-01-01

Malalignment is known to impact the medial-to-lateral load distribution in the tibiofemoral joint. In this longitudinal study, we test the hypothesis that subchondral bone surface areas functionally adapt to the load distribution in malaligned knees. Alignment (hip-knee-ankle angle) was measured from full limb films in 174 participants with knee osteoarthritis. Coronal MR images were acquired at baseline and 26.6±5.4 months later. The subchondral bone surface area of the weight-bearing tibiofemoral cartilages was segmented, with readers blinded to the order of acquisition. The size of the subchondral bone surface areas was computed after triangulation using proprietary software. The hip-knee-ankle angle showed a significant correlation with the tibial (r2=0.25, p<0.0001) and femoral (r2=0.07, p<0.001) ratio of medial-to-lateral subchondral bone surface area. In the tibia, the ratio was significantly different between varus (1.28:1), neutral (1.18:1) and valgus (1.13:1) knees (ANOVA; p<0.00001). Similar observations were made in the weight-bearing femur (0.94:1 in neutral, 0.97.1 in varus, 0.91:1 in valgus knees; ANOVA p=0.018). The annualized longitudinal increase in subchondral bone surface area was significant (p<0.05) in the medial tibia (+0.13%), medial femur (+0.26%) and lateral tibia (+0.19%). In the medial femur, the change between baseline and follow-up was significantly different (ANOVA; p=0.020) between neutral, varus and valgus knees, the increase in surface area being significantly greater (p=0.019) in varus than in neutral knees. Tibiofemoral subchondral bone surface areas are shown to be functionally adapted to the medial-to-lateral load distribution. The longitudinal findings indicate that this adaptational process may continue to take place at advanced age. PMID:19148562

Alpine Cliff Backwearing Rates Derived From Cosmogenic 10-Be in Active Medial Moraines

NASA Astrophysics Data System (ADS)

Ward, D. J.; Anderson, R. S.

2008-12-01

We use cosmogenic 10Be concentrations in rock samples from an active, ice-cored medial moraine to constrain glacial valley sidewall backwearing rates in the Kichatna Mountains, Alaska Range, Alaska. Kilometer-tall granite walls that tower over active glaciers are some of the most dramatic landscape features of the Alaska Range. The sheer scale of the relief speaks to the relative rates of valley incision by glaciers and rockwall retreat, but these rates are difficult to determine independently of one another. We present a method that uses cosmogenic nuclides to measure rockwall backwearing rates in glaciated settings on timescales of 103 yr, with a straightforward sampling strategy that exploits active medial moraines. Ablation-dominated medial moraines form by exhumation of debris-rich ice in the ablation zone of a glacier. Exhumed debris insulates the underlying ice and reduces its ablation rate relative to bare ice, promoting formation of a ridge-like, ice cored moraine. The rock debris is primarily derived from supraglacial rockfalls, which become incorporated in the ice along the glacier margins in the accumulation area. These lateral bands of debris-rich ice merge to form a medial debris band when glacial tributaries converge. The debris is minimally mixed until it is exhumed on the moraine crest. In the simplest case, such a system serves as a conveyor belt, bringing material from a specific part of the ablation zone valley wall to a specific point on a medial moraine in the ablation zone. We collected 5 grab samples, each consisting of ~30 2-10 cm rock fragments of the same lithology, from a 4.5 km longitudinal transect on the crest of the medial moraine of the Shadows glacier. We sampled the crest to minimize the amount of post-exhumation transport and mixing that may have occurred; each sample probably contains rocks from only one to a few rockfall events. Measured 10Be concentrations range from 1.5x104 to 3x104 at/g-qtz and are higher downvalley. First

Medial-Vowel Writing Difficulty in Korean Syllabic Writing: A Characteristic Sign of Alzheimer's Disease

PubMed Central

Yoon, Ji Hye; Jeong, Yong

2018-01-01

Background and Purpose Korean-speaking patients with a brain injury may show agraphia that differs from that of English-speaking patients due to the unique features of Hangul syllabic writing. Each grapheme in Hangul must be arranged from left to right and/or top to bottom within a square space to form a syllable, which requires greater visuospatial abilities than when writing the letters constituting an alphabetic writing system. Among the Hangul grapheme positions within a syllable, the position of a vowel is important because it determines the writing direction and the whole configuration in Korean syllabic writing. Due to the visuospatial characteristics of the Hangul vowel, individuals with early-onset Alzheimer's disease (EOAD) may experiences differences between the difficulties of writing Hangul vowels and consonants due to prominent visuospatial dysfunctions caused by parietal lesions. Methods Eighteen patients with EOAD and 18 age-and-education-matched healthy adults participated in this study. The participants were requested to listen to and write 30 monosyllabic characters that consisted of an initial consonant, medial vowel, and final consonant with a one-to-one phoneme-to-grapheme correspondence. We measured the writing time for each grapheme, the pause time between writing the initial consonant and the medial vowel (P1), and the pause time between writing the medial vowel and the final consonant (P2). Results All grapheme writing and pause times were significantly longer in the EOAD group than in the controls. P1 was also significantly longer than P2 in the EOAD group. Conclusions Patients with EOAD might require a higher judgment ability and longer processing time for determining the visuospatial grapheme position before writing medial vowels. This finding suggests that a longer pause time before writing medial vowels is an early marker of visuospatial dysfunction in patients with EOAD. PMID:29504296

Medial-Vowel Writing Difficulty in Korean Syllabic Writing: A Characteristic Sign of Alzheimer's Disease.

PubMed

Yoon, Ji Hye; Jeong, Yong; Na, Duk L

2018-04-01

Korean-speaking patients with a brain injury may show agraphia that differs from that of English-speaking patients due to the unique features of Hangul syllabic writing. Each grapheme in Hangul must be arranged from left to right and/or top to bottom within a square space to form a syllable, which requires greater visuospatial abilities than when writing the letters constituting an alphabetic writing system. Among the Hangul grapheme positions within a syllable, the position of a vowel is important because it determines the writing direction and the whole configuration in Korean syllabic writing. Due to the visuospatial characteristics of the Hangul vowel, individuals with early-onset Alzheimer's disease (EOAD) may experiences differences between the difficulties of writing Hangul vowels and consonants due to prominent visuospatial dysfunctions caused by parietal lesions. Eighteen patients with EOAD and 18 age-and-education-matched healthy adults participated in this study. The participants were requested to listen to and write 30 monosyllabic characters that consisted of an initial consonant, medial vowel, and final consonant with a one-to-one phoneme-to-grapheme correspondence. We measured the writing time for each grapheme, the pause time between writing the initial consonant and the medial vowel (P1), and the pause time between writing the medial vowel and the final consonant (P2). All grapheme writing and pause times were significantly longer in the EOAD group than in the controls. P1 was also significantly longer than P2 in the EOAD group. Patients with EOAD might require a higher judgment ability and longer processing time for determining the visuospatial grapheme position before writing medial vowels. This finding suggests that a longer pause time before writing medial vowels is an early marker of visuospatial dysfunction in patients with EOAD. Copyright © 2018 Korean Neurological Association.

Early postoperative cartilage evaluation by magnetic resonance imaging using T2 mapping after arthroscopic partial medial meniscectomy.

PubMed

Kato, Kammei; Arai, Yuji; Ikoma, Kazuya; Nakagawa, Shuji; Inoue, Hiroaki; Kan, Hiroyuki; Matsuki, Tomohiro; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2015-12-01

This study was performed to quantitatively evaluate postoperative changes in cartilage by T2 mapping after arthroscopic partial medial meniscectomy. The study enrolled 17 patients with 20 knees that underwent arthroscopic partial medial meniscectomy. MRI was performed preoperatively and at six months postoperatively, with subjects evaluated by T2 mapping of the central part of the medial condyle of the femur in the sagittal plane. Regions of interest (ROIs) were set at 10 points between the point of intersection of the anatomical axis of the femur and the articular surface of the medial condyle and posterior area approximately 90 degrees to the anatomical axis. Pre- and postoperative T2 values at each ROI were evaluated. Postoperative T2 values were significantly longer than preoperative values at approximately 20, 30, 40, and 50 degrees to the anatomical axis of the femur. The maximum change between pre- and postoperative T2 values was +6.65% at 30 degrees to the anatomical axis. Mechanical stress at positions approximately 20, 30, 40, and 50 degrees relative to the anatomical axis of the femur increased soon after arthroscopic medial meniscectomy. These findings indicate the start of degeneration, via disorganization of collagen arrays, of the articular cartilage and increased water content. Copyright © 2015. Published by Elsevier Inc.

Comparison of Clinical Efficacy of Lateral and Lateral and Medial Double-plating Fixation of Distal Femoral Fractures.

PubMed

Bai, Zhibiao; Gao, Shichang; Hu, Zhenming; Liang, Anlin

2018-03-20

The present study was performed to compare the clinical efficacy of lateral plate and lateral and medial double-plating fixation of distal femoral fractures and explore the indication of lateral and medial double-plating fixation of the distal femoral fractures. From March 2006 to April 2014, 48 and 12 cases of distal femoral fractures were treated with lateral plate (single plate) and lateral and medial plates (double plates), respectively. During the surgery, after setting the lateral plate for the distal femoral fractures, if the varus stress test of the knee was positive and the lateral collateral ligament rupture was excluded, lateral and medial double-plating fixation was used for the stability of the fragments. All the patients were followed up at an average period of 15.9 months. The average operation time, the intraoperative hemorrhage and the fracture union time of the two groups were compared. One year after operation, knee function was evaluated by the Kolmert's standard. There was no significant difference in the average operation time, intraoperative hemorrhage, fracture healing time and excellent and good rates of postoperative knee function between two groups. Positive Varus stress test during operation can be an indication for lateral and medial double-plating fixation of distal femoral fractures.

Recollection of episodic memory within the medial temporal lobe: behavioural dissociations from other types of memory.

PubMed

Easton, Alexander; Eacott, Madeline J

2010-12-31

In recent years there has been significant debate about whether there is a single medial temporal lobe memory system or dissociable systems for episodic and other types of declarative memory. In addition there has been a similar debate over the dissociability of recollection and familiarity based processes in recognition memory. Here we present evidence from recent work using episodic memory tasks in animals that allows us to explore these issues in more depth. We review studies that demonstrate triple dissociations within the medial temporal lobe, with only the hippocampal system being necessary for episodic memory. Similarly we review behavioural evidence for a dissociation in a task of episodic memory in rats where animals with lesions of the fornix are only impaired at recollection of the episodic memory, not recognition within the same trial. This work, then, supports recent models of dissociable neural systems within the medial temporal lobe but also raises questions for future investigation about the interactions of these medial temporal lobe memory systems with other structures. Copyright © 2009 Elsevier B.V. All rights reserved.

The phylogenetic distribution, anatomy and histology of the post-cloacal bones and adnexa of geckos.

PubMed

Russell, Anthony P; Vickaryous, Matthew K; Bauer, Aaron M

2016-02-01

Post-cloacal bones of gekkotans may be present as a single (medial) pair, two pairs (medial and lateral), or may be lacking. We, herein, demonstrate that the presence of a single medial pair is the ancestral condition for the Gekkota, that the lateral pair is of sporadic occurrence within and between families, except for the Eublepharidae where it is universal, and that absence is also of sporadic occurrence except for the Sphaerodactylidae where it is the ancestral condition. Adult male Tokay geckos (Gekko gecko) possess only the medial pair of bones, and these exhibit a regionally-specific expression of woven, fibrolamellar, and lamellar bone, and an enclosed medullary cavity. Females and small juvenile males lack bony elements but exhibit a conspicuous band of dense connective tissue located about the anterior and lateral margins of the cloacal sacs. As males grow and attain sexual maturity, the medial post-cloacal bones condense in this band of dense connective tissue, and are thus shown to be dermal ossifications, similar to osteoderms but with muscular associations (although this is also known for crocodylians). Based upon ontogenetic data we set forth a scenario to explain the loss of the medial post-cloacal bones in various lineages. Differential staining of the cloacal sacs failed to reveal any specialized glandular structures. Investigation of the post-cloacal spurs shows them to be associated with cellular connective tissue of a type similar to that found in the vicinity of the medial post-cloacal bones. This suggests that the lateral post-cloacal bones may also be dermal bones, but histological evidence is needed to corroborate this. © 2015 Wiley Periodicals, Inc.

Base pair probability estimates improve the prediction accuracy of RNA non-canonical base pairs

PubMed Central

2017-01-01

Prediction of RNA tertiary structure from sequence is an important problem, but generating accurate structure models for even short sequences remains difficult. Predictions of RNA tertiary structure tend to be least accurate in loop regions, where non-canonical pairs are important for determining the details of structure. Non-canonical pairs can be predicted using a knowledge-based model of structure that scores nucleotide cyclic motifs, or NCMs. In this work, a partition function algorithm is introduced that allows the estimation of base pairing probabilities for both canonical and non-canonical interactions. Pairs that are predicted to be probable are more likely to be found in the true structure than pairs of lower probability. Pair probability estimates can be further improved by predicting the structure conserved across multiple homologous sequences using the TurboFold algorithm. These pairing probabilities, used in concert with prior knowledge of the canonical secondary structure, allow accurate inference of non-canonical pairs, an important step towards accurate prediction of the full tertiary structure. Software to predict non-canonical base pairs and pairing probabilities is now provided as part of the RNAstructure software package. PMID:29107980

A rare type of ankle fracture: Syndesmotic rupture combined with a high fibular fracture without medial injury.

PubMed

van Wessem, K J P; Leenen, L P H

2016-03-01

High fibular spiral fractures are usually caused by pronation-external rotation mechanism. The foot is in pronation and the talus externally rotates, causing a rupture of the medial ligaments or a fracture of the medial malleolus. With continued rotation the anterior and posterior tibiofibular ligament will rupture, and finally, the energy leaves the fibula by creating a spiral fracture from anterior superior to posterior inferior. In this article we demonstrate a type of ankle fracture with syndesmotic injury and high fibular spiral fractures without a medial component. This type of ankle fractures cannot be explained by the Lauge-Hansen classification, since it lacks injury on the medial side of the ankle, but it does have the fibular fracture pattern matching the pronation external rotation injury (anterior superior to posterior inferior fracture). We investigated the mechanism of this injury illustrated by 3 cases and postulate a theory explaining the biomechanics behind this type of injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

Medial Meniscus Posterior Root Tear Repair Using a 2-Simple-Suture Pullout Technique.

PubMed

Samy, Tarek Mohamed; Nassar, Wael A M; Zakaria, Zeiad Mohamed; Farrag Abdelaziz, Ahmed Khaled

2017-06-01

Medial meniscus posterior root tear is one of the underestimated knee injuries in terms of incidence. Despite its grave sequelae, using simple but effective technique can maintain the native knee joint longevity. In the current note, a 2-simple-suture pullout technique was used to effectively reduce the meniscus posterior root to its anatomic position. The success of the technique depended on proper tool selection as well as tibial tunnel direction that allowed easier root suturing and better suture tensioning, without inducing any iatrogenic articular cartilage injury or meniscal tissue loss. Using anterior knee arthroscopy portals, anterolateral as a viewing portal and anteromedial as a working portal, a 7-mm tibial tunnel starting at Gerdy tubercle and ending at the medial meniscus posterior root bed was created. The 2 simple sutures were retrieved through the tunnel and tensioned and secured over a 12-mm-diameter washer at the tibial tunnel outer orifice. Anatomic reduction of the medial meniscus posterior root tear was confirmed arthroscopically intraoperatively and radiologically by postoperative magnetic resonance imaging.

Effects of medially wedged foot orthoses on knee and hip joint running mechanics in females with and without patellofemoral pain syndrome.

PubMed

Boldt, Andrew R; Willson, John D; Barrios, Joaquin A; Kernozek, Thomas W

2013-02-01

We examined the effects of medially wedged foot orthoses on knee and hip joint mechanics during running in females with and without patellofemoral pain syndrome (PFPS). We also tested if these effects depend on standing calcaneal eversion angle. Twenty female runners with and without PFPS participated. Knee and hip joint transverse and frontal plane peak angle, excursion, and peak internal knee and hip abduction moment were calculated while running with and without a 6° full-length medially wedged foot orthoses. Separate 3-factor mixed ANOVAs (group [PFPS, control] x condition [medial wedge, no medial wedge] x standing calcaneal angle [everted, neutral, inverted]) were used to test the effect of medially wedged orthoses on each dependent variable. Knee abduction moment increased 3% (P = .03) and hip adduction excursion decreased 0.6° (P < .01) using medially wedged foot orthoses. No significant group x condition or calcaneal angle x condition effects were observed. The addition of medially wedged foot orthoses to standardized running shoes had minimal effect on knee and hip joint mechanics during running thought to be associated with the etiology or exacerbation of PFPS symptoms. These effects did not appear to depend on injury status or standing calcaneal posture.

Effect of partial meniscectomy at the medial posterior horn on tibiofemoral contact mechanics and meniscal hoop strains in human knees.

PubMed

Seitz, Andreas Martin; Lubomierski, Anja; Friemert, Benedikt; Ignatius, Anita; Dürselen, Lutz

2012-06-01

We examined the influence of partial meniscectomy of 10 mm width on 10 human cadaveric knee joints, as it is performed during the treatment of radial tears in the posterior horn of the medial meniscus, on maximum contact pressure, contact area (CA), and meniscal hoop strain in the lateral and medial knee compartments. In case of 0° and 30° flexion angle, 20% and 50% partial meniscectomy did not influence maximum contact pressure and area. Only in case of 60° knee flexion, 50% partial resection increased medial maximum contact pressure and decreased the medial CA statistically significant. However, 100% partial resection increased maximum contact pressure and decreased CA significantly in the meniscectomized medial knee compartment in all tested knee positions. No significant differences were noted for meniscal hoop strain. From a biomechanical point of view, our in vitro study suggests that the medial joint compartment is not in danger of accelerated cartilage degeneration up to a resection limit of 20% meniscal depth and 10 mm width. Contact mechanics are likely to be more sensitive to partial meniscectomy at higher flexion angles, which has to be further investigated. Copyright © 2011 Orthopaedic Research Society.

Medial gastrocnemius and soleus muscle-tendon unit, fascicle, and tendon interaction during walking in children with cerebral palsy.

PubMed

Barber, Lee; Carty, Chris; Modenese, Luca; Walsh, John; Boyd, Roslyn; Lichtwark, Glen

2017-08-01

This study investigates the in vivo function of the medial gastrocnemius and soleus muscle-tendon units (MTU), fascicles, and tendons during walking in children with cerebral palsy (CP) and an equinus gait pattern. Fourteen children with CP (9 males, 5 females; mean age 10y 6mo, standard deviation [SD] 2y 11mo; GMFCS level I=8, II=6), and 10 typically developing (6 males, 4 females; mean age 10y, SD 2y 1mo) undertook full body 3D gait analysis and simultaneous B-mode ultrasound images of the medial gastrocnemius and soleus fascicles during level walking. Fascicle lengths were analysed using a semi-automated tracking algorithm and MTUs using OpenSim. Statistical parametric mapping (two-sample t-test) was used to compare differences between groups (p<0.05). In the CP group medial gastrocnemius fascicles lengthened during mid-stance gait and remained longer into late-stance compared to the typically developing group (p<0.001). CP medial gastrocnemius fascicles shortened less during stance (1.16mm [SD 1.47mm]) compared to the typically developing group (4.48mm [SD 1.94mm], p<0.001). In the CP group the medial gastrocnemius and soleus MTU and tendon were longer during early- and mid-stance (p<0.001). Ankle power during push-off (p=0.015) and positive work (p<0.002) and net work (p<0.001) were significantly lower in the CP group. Eccentric action of the CP medial gastrocnemius muscle fascicles during mid-stance walking is consistent with reduced volume and neuromuscular control of impaired muscle. Reduced ankle push-off power and positive work in the children with CP may be attributed to reduced active medial gastrocnemius fascicle shortening. These findings suggest a reliance on passive force generation for forward propulsion during equinus gait. © 2017 Mac Keith Press.

Functional outcome of vocal fold medialization thyroplasty with a hydroxyapatite implant.

PubMed

Storck, Claudio; Brockmann, Meike; Schnellmann, Elvira; Stoeckli, Sandro J; Schmid, Stephan

2007-06-01

Unilateral vocal fold paralysis can cause a persistent incomplete glottal closure during phonation, resulting in impaired voice function. The aim of this study was to evaluate functional results of medialization thyroplasty using a hydroxyapatite implant (VoCoM). Prospective observational cohort study. Between 1999 and 2003, a total of 26 patients (19 men, 7 women) undergoing medialization thyroplasty using a hydroxyapatite implant because of unilateral vocal fold paralysis were enrolled in the study. To evaluate voice function, the following parameters were measured preoperatively and postoperatively: mean fundamental frequency, mean sound pressure level, frequency and amplitude range (voice range profile), and maximum phonation time. A perceptual assessment of hoarseness was conducted using the Roughness, Breathiness, Hoarseness scale. Furthermore, the magnitude of voice related impairment of the patient's communication skills was rated on a 7-point scale. A combined parameter called the Voice Dysfunction Index (VDI) was used to rate vocal performance. All patients showed a statistically significant improvement in the VDI, in perceptual voice analysis, in maximum phonation time, and in the dynamic range of voice. One patient experienced a postoperative wound hemorrhage as a minor complication. No further complications or implant extrusions were observed. Medialization thyroplasty using a hydroxyapatite implant is a secure and efficient phonosurgical procedure. Voice quality and patient satisfaction improve significantly after treatment.

In vivo tibiofemoral cartilage-to-cartilage contact area of females with medial osteoarthritis under acute loading using MRI.

PubMed

Shin, Choongsoo S; Souza, Richard B; Kumar, Deepak; Link, Thomas M; Wyman, Bradley T; Majumdar, Sharmila

2011-12-01

To investigate the effect of acute loading on in vivo tibiofemoral contact area changes in both compartments, and to determine whether in vivo tibiofemoral contact area differs between subjects with medial knee osteoarthritis (OA) and healthy controls. Ten subjects with medial knee OA (KL3) and 11 control subjects (KL0) were tested. Coronal three-dimensional spoiled gradient-recalled (3D-SPGR) and T(2) -weighted fast spin-echo FSE magnetic resonance imaging (MRI) of the knee were acquired under both unloaded and loaded conditions. Tibiofemoral cartilage contact areas were measured using image-based 3D models. Tibiofemoral contact areas in both compartments significantly increased under loading (P < 0.001) and the increased contact area in the medial compartment was significantly larger than in the lateral compartment (P < 0.05). Medial compartment contact area was significantly larger in KL3 subjects than KL0 subjects, both at unloaded and loaded conditions (P < 0.05). Contact areas measured from 3D-SPGR and T(2) -weighted FSE images were strongly correlated (r = 0.904). Females with medial OA increased tibiofemoral contact area in the medial compartment compared to healthy subjects under both unloaded and loaded conditions. The contact area data presented in this study may provide a quantitative reference for further cartilage contact biomechanics such as contact stress analysis and cartilage biomechanical function difference between osteoarthritic and healthy knees. Copyright © 2011 Wiley Periodicals, Inc.

Prospective very young asteroid pairs

NASA Astrophysics Data System (ADS)

Galád, A.; Vokrouhlický, D.; Zizka, J.

2014-07-01

Several tens of asteroid pairs can be discerned from the background main-belt asteroids. The majority of them are thought to have formed within only the last few 10^6 yr. The youngest recognized pairs have formed more than ≈ 10 kyr ago. As some details of pair formation are still not understood well, the study of young pairs is of great importance. It is mainly because the conditions at the time of the pair formation could be deduced much more reliably for young pairs. For example, space weathering on the surfaces of the components, or changes in their rotational properties (in spin rates, tumbling, coordinates of rotational pole) could be negligible since the formation of young pairs. Also, possible strong perturbations by main-belt bodies on pair formation can be reliably studied only for extremely young pairs. Some pairs can quickly blend in with the background asteroids, so even the frequency of asteroid pair formation could be determined more reliably based on young pairs (though only after a statistically significant sample is at disposal). In our regular search for young pairs in the growing asteroid database, only multiopposition asteroids with very similar orbital and proper elements are investigated. Every pair component is represented by a number of clones within orbital uncertainties and drifting in semimajor axis due to the Yarkovsky effect. We found that, if the previously unrecognized pairs (87887) 2000 SS_{286} - 2002 AT_{49} and (355258) 2007 LY_{4} - 2013AF_{40} formed at the recent very close approach of their components, they could become the youngest known pairs. In both cases, the relative encounter velocities of the components were only ˜ 0.1 m s^{-1}. However, the minimum distances between some clones are too large and a few clones of the latter pair did not encounter recently (within ≈ 10 kyr). The age of some prospective young pairs cannot be determined reliably without improved orbital properties (e.g., the second component of a pair

Differences in Medial and Lateral Posterior Tibial Slope: An Osteological Review of 1090 Tibiae Comparing Age, Sex, and Race.

PubMed

Weinberg, Douglas S; Williamson, Drew F K; Gebhart, Jeremy J; Knapik, Derrick M; Voos, James E

2017-01-01

Injuries to the anterior cruciate ligament (ACL) are common, and a number of knee morphological variables have been identified as risk factors for an ACL injury, including the posterior tibial slope (TS). However, limited data exist regarding innate population differences in the TS. To (1) establish normative values for the medial and lateral posterior TS; (2) determine what differences exist between ages, sexes, and races; and (3) determine how internal or external tibial rotation (as occurs during sagittal knee motion) influences the stereotactic perception of the TS. Cross-sectional study; Level of evidence, 3. A total of 545 cadaveric specimens (1090 tibiae) were obtained from the Hamann-Todd osteological collection. Specimens were leveled in the coronal, sagittal, and axial planes using a digital laser. Virtual representations of each bone were created with a 3-dimensional digitizer apparatus. The TS of the medial and lateral tibial plateaus were measured using techniques adapted from previous radiographic protocols. Medial and lateral TS were then again measured on 200 tibiae that were internally and externally rotated by 10° (axially). The mean (±SD) medial TS was 6.9° ± 3.7° posterior, which was greater than the mean lateral TS of 4.7° ± 3.6° posterior ( P < .001). Neither the medial nor lateral TS changed with age. Women had a greater mean TS compared with men on both the medial (7.5° ± 3.8° vs 6.8° ± 3.7°, respectively; P = .03) and lateral (5.2° ± 3.5° vs 4.6° ± 3.5°, respectively; P = .04) sides. Black specimens had a greater mean medial TS (8.7° ± 3.6° vs 5.8° ± 3.3°, respectively; P < .001) and lateral TS (5.9° ± 3.3° vs 3.8° ± 3.5°, respectively; P < .001) compared with white specimens. Axial rotation was shown to increase the perception of the medial and lateral TS ( P < .001). The medial TS was shown to be greater than the lateral TS. Important sex- and race-based differences exist in the TS. This study also

Paired Comparisons.

DTIC Science & Technology

1982-05-01

including multidimensional scaling. Applications have arisen in many areas, but most notably in food technolog, marketing research, and sports ... competition .- An extensive bibliography on paired comparisons by Davidson and Farquhar (1976) contains some 400 references. - Paired comparisons have been...consideration of chess competition . Ford (1957) pro- posed the model independently. Both Zermelo and Ford concentrated on solution of normal equations for

Relationship between knee joint contact forces and external knee joint moments in patients with medial knee osteoarthritis: effects of gait modifications.

PubMed

Richards, R E; Andersen, M S; Harlaar, J; van den Noort, J C

2018-04-30

To evaluate 1) the relationship between the knee contact force (KCF) and knee adduction and flexion moments (KAM and KFM) during normal gait in people with medial knee osteoarthritis (KOA), 2) the effects on the KCF of walking with a modified gait pattern and 3) the relationship between changes in the KCF and changes in the knee moments. We modeled the gait biomechanics of thirty-five patients with medial KOA using the AnyBody Modeling System during normal gait and two modified gait patterns. We calculated the internal KCF and evaluated the external joint moments (KAM and KFM) against it using linear regression analyses. First peak medial KCF was associated with first peak KAM (R 2  = 0.60) and with KAM and KFM (R 2  = 0.73). Walking with both modified gait patterns reduced KAM (P = 0.002) and the medial to total KCF ratio (P < 0.001) at the first peak. Changes in KAM during modified gait were moderately associated with changes in the medial KCF at the first peak (R 2  = 0.54 and 0.53). At the first peak, KAM is a reasonable substitute for the medial contact force, but not at the second peak. First peak KFM is also a significant contributor to the medial KCF. At the first peak, walking with a modified gait reduced the ratio of the medial to total KCF but not the medial KCF itself. To determine the effects of gait modifications on cartilage loading and disease progression, longitudinal studies and individualized modeling, accounting for motion control, would be required. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Posterior root tear of the medial and lateral meniscus.

PubMed

Petersen, Wolf; Forkel, Philipp; Feucht, Matthias J; Zantop, Thore; Imhoff, Andreas B; Brucker, Peter U

2014-02-01

An avulsion of the tibial insertion of the meniscus or a radial tear close to the meniscal insertion is defined as a root tear. In clinical practice, the incidence of these lesions is often underestimated. However, several biomechanical studies have shown that the effect of a root tear is comparable to a total meniscectomy. Clinical studies documented progredient arthritic changes following root tears, thereby supporting basic science studies. The clinical diagnosis is limited by unspecific symptoms. In addition to the diagnostic arthroscopy, MRI is considered to be the gold standard of diagnosis of a meniscal root tear. Three different direct MRI signs for the diagnosis of a meniscus root tear have been described: Radial linear defect in the axial plane, vertical linear defect (truncation sign) in the coronal plane, and the so-called ghost meniscus sign in the sagittal plane. Meniscal extrusion is also considered to be an indirect sign of a root tear, but is less common in lateral root tears. During arthroscopy, the function of the meniscus root must be assessed by probing. However, visualization of the meniscal insertions is challenging. Refixation of the meniscal root can be performed using a transtibial pull-out suture, suture anchors, or side-to-side repair. Several short-term studies reported good clinical results after medial or lateral root repair. Nevertheless, MRI and second-look arthroscopy revealed high rates of incomplete or absent healing, especially for medial root tears. To date, most studies are case series with short-term follow-up and level IV evidence. Outerbridge grade 3 or 4 chondral lesions and varus malalignment of >5° were found to predict an inferior clinical outcome after medial meniscus root repair. Further research is needed to evaluate long-term results and to define evident criteria for meniscal root repair.

Medial tibial pain: a dynamic contrast-enhanced MRI study.

PubMed

Mattila, K T; Komu, M E; Dahlström, S; Koskinen, S K; Heikkilä, J

1999-09-01

The purpose of this study was to compare the sensitivity of different magnetic resonance imaging (MRI) sequences to depict periosteal edema in patients with medial tibial pain. Additionally, we evaluated the ability of dynamic contrast-enhanced imaging (DCES) to depict possible temporal alterations in muscular perfusion within compartments of the leg. Fifteen patients with medial tibial pain were examined with MRI. T1-, T2-weighted, proton density axial images and dynamic and static phase post-contrast images were compared in ability to depict periosteal edema. STIR was used in seven cases to depict bone marrow edema. Images were analyzed to detect signs of compartment edema. Region-of-interest measurements in compartments were performed during DCES and compared with controls. In detecting periosteal edema, post-contrast T1-weighted images were better than spin echo T2-weighted and proton density images or STIR images, but STIR depicted the bone marrow edema best. DCES best demonstrated the gradually enhancing periostitis. Four subjects with severe periosteal edema had visually detectable pathologic enhancement during DCES in the deep posterior compartment of the leg. Percentage enhancement in the deep posterior compartment of the leg was greater in patients than in controls. The fast enhancement phase in the deep posterior compartment began slightly slower in patients than in controls, but it continued longer. We believe that periosteal edema in bone stress reaction can cause impairment of venous flow in the deep posterior compartment. MRI can depict both these conditions. In patients with medial tibial pain, MR imaging protocol should include axial STIR images (to depict bone pathology) with T1-weighted axial pre and post-contrast images, and dynamic contrast enhanced imaging to show periosteal edema and abnormal contrast enhancement within a compartment.

Calibrated fMRI in the Medial Temporal Lobe During a Memory Encoding Task

PubMed Central

Restom, Khaled; Perthen, Joanna E.; Liu, Thomas T.

2008-01-01

Prior measures of the blood oxygenation level dependent (BOLD) and cerebral blood flow (CBF) responses to a memory encoding task within the medial temporal lobe have suggested that the coupling between functional changes in CBF and changes in the cerebral metabolic rate of oxgyen (CMRO2) may be tighter in the medial temporal lobe as compared to the primary sensory areas. In this study, we used a calibrated functional magnetic resonance imaging (fMRI) approach to directly estimate memory-encoding-related changes in CMRO2 and to assess the coupling between CBF and CMRO2 in the medial temporal lobe. The CBF-CMRO2 coupling ratio was estimated using a linear fit to the flow and metabolism changes observed across subjects. In addition, we examined the effect of region-of-interest (ROI) selection on the estimates. In response to the memory encoding task, CMRO2 increased by 23.1% ± 8.8 to 25.3% ± 5.7 (depending upon ROI), with an estimated CBF-CMRO2 coupling ratio of 1.66 ± 0.07 to 1.75± 0.16. There was not a significant effect of ROI selection on either the CMRO2 or coupling ratio estimates. The observed coupling ratios were significantly lower than the values (2 to 4.5) that have been reported in previous calibrated fMRI studies of the visual and motor cortices. In addition, the estimated coupling ratio was found to be less sensitive to the calibration procedure for functional responses in the medial temporal lobe as compared to the primary sensory areas. PMID:18329291

Medial Temporal Lobe Structures Contribute to On-Line Processing

ERIC Educational Resources Information Center

Warren, David

2009-01-01

For the last five decades, the medial temporal lobes have been generally understood to facilitate enduring representation of certain kinds of information. In particular, knowledge about the relations among items and concepts appears to rely on that region of the brain. Recent results suggest that those same structures also play a subtle role in…

Incarcerated medial epicondyle fracture following pediatric elbow dislocation: 11 cases.

PubMed

Dodds, Seth D; Flanagin, Brody A; Bohl, Daniel D; DeLuca, Peter A; Smith, Brian G

2014-09-01

To describe outcomes after surgical management of pediatric elbow dislocation with incarceration of the medial epicondyle. We conducted a retrospective case review of 11 consecutive children and adolescents with an incarcerated medial epicondyle fracture after elbow dislocation. All patients underwent open reduction internal fixation using a similar technique. We characterized outcomes at final follow-up. Average follow-up was 14 months (range, 4-56 mo). All patients had clinical and radiographic signs of healing at final follow-up. There was no radiographic evidence of loss of reduction at intervals or at final follow-up. There were no cases of residual deformity or valgus instability. Average final arc of elbow motion was 4° to 140°. All patients had forearm rotation from 90° supination to 90° pronation. Average Mayo elbow score was 99.5. Four of 11 patients had ulnar nerve symptoms postoperatively and 1 required a second operation for ulnar nerve symptoms. In addition, 1 required a second operation for flexion contracture release with excision of heterotopic ossification. Three patients had ulnar nerve symptoms at final follow-up. Two of these had mild paresthesia only and 1 had both mild paresthesia and weakness. Our results suggest that open reduction internal fixation of incarcerated medial epicondyle fractures after elbow dislocation leads to satisfactory motion and function; however, the injury carries a high risk for complications, particularly ulnar neuropathy. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Modulating Phonation Through Alteration of Vocal Fold Medial Surface Contour

PubMed Central

Mau, Ted; Muhlestein, Joseph; Callahan, Sean; Chan, Roger W.

2012-01-01

Objectives 1. To test whether alteration of the vocal fold medial surface contour can improve phonation. 2. To demonstrate that implant material properties affect vibration even when implant is deep to the vocal fold lamina propria. Study Design Induced phonation of excised human larynges. Methods Thirteen larynges were harvested within 24 hours post-mortem. Phonation threshold pressure (PTP) and flow (PTF) were measured before and after vocal fold injections using either calcium hydroxylapatite (CaHA) or hyaluronic acid (HA). Small-volume injections (median 0.0625 mL) were targeted to the infero-medial aspect of the thyroarytenoid (TA) muscle. Implant locations were assessed histologically. Results The effect of implantation on PTP was material-dependent. CaHA tended to increase PTP, whereas HA tended to decrease PTP (Wilcoxon test P = 0.00013 for onset). In contrast, the effect of implantation on PTF was similar, with both materials tending to decrease PTF (P = 0.16 for onset). Histology confirmed implant presence in the inferior half of the vocal fold vertical thickness. Conclusions Taken together, these data suggested the implants may have altered the vocal fold medial surface contour, potentially resulting in a less convergent or more rectangular glottal geometry as a means to improve phonation. An implant with a closer viscoelastic match to vocal fold cover is desirable for this purpose, as material properties can affect vibration even when the implant is not placed within the lamina propria. This result is consistent with theoretical predictions and implies greater need for surgical precision in implant placement and care in material selection. PMID:22865592

Arthroscopic partial meniscectomy of a medial meniscus bucket-handle tear using the posteromedial portal.

PubMed

Ahn, Jin Hwan; Oh, Irvin

2004-09-01

Arthroscopic resection of irreparable bucket-handle tears of the medial meniscus is a commonly performed procedure. Adequate visualization of the posterior horn of the medial meniscus can be a challenging task with the conventional use of the anterior portal. An attempt to resect the posterior horn in a blind fashion may result in iatrogenic damage of the articular cartilage in the posterior compartment, over-resection of a remnant meniscus, or an insufficient resection of the torn fragment. We describe the use of the posteromedial portal for an accurate visualization and resection of the posterior attachment of a bucket-handle tear for arthroscopic partial meniscectomy, as well as detection of other injuries that may be involved in the posteromedial compartment, while avoiding injury to other intra-articular structures during the arthroscopic procedure. We found that the use of the posteromedial portal is a safe and efficient method in removing a bucket-handle tear of the medial meniscus in one piece.

Sinonasal organised haematoma: clinical features and successful application of modified transnasal endoscopic medial maxillectomy.

PubMed

Suzuki, M; Nakamura, Y; Ozaki, S; Yokota, M; Murakami, S

2017-08-01

Although organised haematoma often induces bone thinning and destruction similar to malignant diseases, the aetiology of organised haematoma and the optimal treatment remain unclear. This paper presents the clinical features of individuals with organised haematoma, and describes cases in which a novel modified approach was successfully applied for resection of organised haematoma in the maxillary sinus. Pre-operative examination data were evaluated retrospectively. Modified transnasal endoscopic medial maxillectomy was employed. Fourteen patients with organised haematoma were treated. Contrast-enhanced computed tomography showed heterogeneous enhancement in all patients. Eight patients underwent modified transnasal endoscopic medial maxillectomy, without complications such as facial numbness, tooth numbness, facial tingling, lacrimation and eye discharge. Dissection of the apertura piriformis and anterior maxillary wall was not necessary for any of these eight patients. No recurrence was observed. Pre-operative examinations can be helpful in determining the likelihood of organised haematoma. Modified transnasal endoscopic medial maxillectomy appears to be a safe and effective method for organised haematoma resection.

Fornix and medial temporal lobe lesions lead to comparable deficits in complex visual perception.

PubMed

Lech, Robert K; Koch, Benno; Schwarz, Michael; Suchan, Boris

2016-05-04

Recent research dealing with the structures of the medial temporal lobe (MTL) has shifted away from exclusively investigating memory-related processes and has repeatedly incorporated the investigation of complex visual perception. Several studies have demonstrated that higher level visual tasks can recruit structures like the hippocampus and perirhinal cortex in order to successfully perform complex visual discriminations, leading to a perceptual-mnemonic or representational view of the medial temporal lobe. The current study employed a complex visual discrimination paradigm in two patients suffering from brain lesions with differing locations and origin. Both patients, one with extensive medial temporal lobe lesions (VG) and one with a small lesion of the anterior fornix (HJK), were impaired in complex discriminations while showing otherwise mostly intact cognitive functions. The current data confirmed previous results while also extending the perceptual-mnemonic theory of the MTL to the main output structure of the hippocampus, the fornix. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The Effects of a Functional Elbow Brace on Medial Joint Stability: A Case Study

PubMed Central

Pincivero, Danny M.; Rijke, Arie M.; Heinrichs, Kristinn; Perrin, David H.

1994-01-01

Medical elbow ligament sprains in athletics can be traumatic and disabling. In this case report, we outline the effect of a prototype functional elbow brace on joint stability in a female collegiate javelin thrower with an ulnar collateral ligament sprain. A valgus force to both elbows was applied using graded stress radiography (Telos GA-II/E stress device) at 0, 5, 10, and 15 kiloPascals (kPa) of pressure. The increase in gap width between the coronoid process and the medial epicondyle was measured from anteroposterior radiographs to determine medial displacement. The brace resulted in less displacement in both injured and noninjured ulnar collateral ligament; injured ulnar collateral ligament demonstrated greater displacement regardless of condition. The brace restored medial stability to the elbow joint by 49%, 38%, and 35% at 5, 10, and 15 kPa of pressure, respectively. The application of the brace may be useful in athletes with ulnar collateral ligament injuries. ImagesFig 1Fig 2 PMID:16558285

Report on Pairing-based Cryptography.

PubMed

Moody, Dustin; Peralta, Rene; Perlner, Ray; Regenscheid, Andrew; Roginsky, Allen; Chen, Lily

2015-01-01

This report summarizes study results on pairing-based cryptography. The main purpose of the study is to form NIST's position on standardizing and recommending pairing-based cryptography schemes currently published in research literature and standardized in other standard bodies. The report reviews the mathematical background of pairings. This includes topics such as pairing-friendly elliptic curves and how to compute various pairings. It includes a brief introduction to existing identity-based encryption (IBE) schemes and other cryptographic schemes using pairing technology. The report provides a complete study of the current status of standard activities on pairing-based cryptographic schemes. It explores different application scenarios for pairing-based cryptography schemes. As an important aspect of adopting pairing-based schemes, the report also considers the challenges inherent in validation testing of cryptographic algorithms and modules. Based on the study, the report suggests an approach for including pairing-based cryptography schemes in the NIST cryptographic toolkit. The report also outlines several questions that will require further study if this approach is followed.

Report on Pairing-based Cryptography

PubMed Central

Moody, Dustin; Peralta, Rene; Perlner, Ray; Regenscheid, Andrew; Roginsky, Allen; Chen, Lily

2015-01-01

This report summarizes study results on pairing-based cryptography. The main purpose of the study is to form NIST’s position on standardizing and recommending pairing-based cryptography schemes currently published in research literature and standardized in other standard bodies. The report reviews the mathematical background of pairings. This includes topics such as pairing-friendly elliptic curves and how to compute various pairings. It includes a brief introduction to existing identity-based encryption (IBE) schemes and other cryptographic schemes using pairing technology. The report provides a complete study of the current status of standard activities on pairing-based cryptographic schemes. It explores different application scenarios for pairing-based cryptography schemes. As an important aspect of adopting pairing-based schemes, the report also considers the challenges inherent in validation testing of cryptographic algorithms and modules. Based on the study, the report suggests an approach for including pairing-based cryptography schemes in the NIST cryptographic toolkit. The report also outlines several questions that will require further study if this approach is followed. PMID:26958435

Etiologic factors in the development of medial tibial stress syndrome: a review of the literature.

PubMed

Tweed, Jo L; Avil, Steven J; Campbell, Jackie A; Barnes, Mike R

2008-01-01

Medial tibial stress syndrome is a type of exercise-induced leg pain that is common in recreational and competitive athletes. Although various studies have attempted to find the exact pathogenesis of this common condition, it remains unknown. Various theories in literature from 1976 to 2006 were reviewed using key words. Until recently, inflammation of the periosteum due to excessive traction was thought to be the most likely cause of medial tibial stress syndrome. This periostitis has been hypothesized by some authors to be caused by the tearing away of the muscle fibers at the muscle-bone interface, although there are several suggestions as to which, if any, muscle is responsible. Recent studies have supported the view that medial tibial stress syndrome is not an inflammatory process of the periosteum but instead a stress reaction of bone that has become painful.

Glutamate microinjection in the medial septum of rats decreases paradoxical sleep and increases slow wave sleep.

PubMed

Mukherjee, Didhiti; Kaushik, Mahesh K; Jaryal, Ashok Kumar; Kumar, Velayudhan Mohan; Mallick, Hruda Nanda

2012-05-09

The role of the medial septum in suppressing paradoxical sleep and promoting slow wave sleep was suggested on the basis of neurotoxic lesion studies. However, these conclusions need to be substantiated with further experiments, including chemical stimulation studies. In this report, the medial septum was stimulated in adult male rats by microinjection of L-glutamate. Sleep-wakefulness was electrophysiologically recorded, through chronically implanted electrodes, for 2 h before the injection and 4 h after the injection. There was a decrease in paradoxical sleep during the first hour and an increase in slow wave sleep during the second hour after the injection. The present findings not only supported the lesion studies but also showed that the major role of the medial septum is to suppress paradoxical sleep.

Computation of the three-dimensional medial surface dynamics of the vocal folds.

PubMed

Döllinger, Michael; Berry, David A

2006-01-01

To increase our understanding of pathological and healthy voice production, quantitative measurement of the medial surface dynamics of the vocal folds is significant, albeit rarely performed because of the inaccessibility of the vocal folds. Using an excised hemilarynx methodology, a new calibration technique, herein referred to as the linear approximate (LA) method, was introduced to compute the three-dimensional coordinates of fleshpoints along the entire medial surface of the vocal fold. The results were compared with results from the direct linear transform. An associated error estimation was presented, demonstrating the improved accuracy of the new method. A test on real data was reported including computation of quantitative measurements of vocal fold dynamics.

Medial Prefrontal Cortex Activity When Thinking About Others Depends on Their Age

PubMed Central

Ebner, Natalie C.; Gluth, Sebastian; Johnson, Matthew R.; Raye, Carol L.; Mitchell, Karen J.; Johnson, Marcia K.

2011-01-01

This functional magnetic resonance imaging (fMRI) study examined medial prefrontal cortex (mPFC) activity as young and older participants rated an unknown young and older person, and themselves, on personality characteristics. For both young and older participants, there was greater activation in ventral mPFC (anterior cingulate) when they made judgments about own-age than other-age individuals. Additionally, across target age and participant age, there was greater activity in a more anterior region of ventral mPFC (largely medial frontal gyrus, anterior cingulate) when participants rated others than when they rated themselves. We discuss potential interpretations of these findings in the context of previous results suggesting functional specificity of subregions of ventral mPFC. PMID:21432722

Classification of the maxillary sinus according to area of the medial antral wall: a comparison of two ethnic groups.

PubMed

Lee, Fernandes Carmen; Fernandes, C M C; Murrell, H C

2009-06-01

This study is an anatomical study designed to benefit surgeons working in the region of the maxillary sinus. This paper investigates ethnic and gender variations in the shape of the maxillary sinus in dried crania from the Raymond Dart collection of human skeletons. The paper claims that an estimate of the area of the medial antral wall of the maxillary sinus is one of the best ethnic/gender group predictors. Helical, multislice computed tomography was performed using 1mm coronal slices length, depth, width and volume measurements for each sinus were taken. Classification by shape and estimated area of medial wall was attempted. Shape classification was found to be unsuccessful whilst medial wall classification into ethnic/gender groupings gave encouraging results. The area of the medial wall is related to ethnic/gender groups.

[Repair of soft tissue defect in hand or foot with lobulated medial sural artery perforator flap].

PubMed

Fengjing, Zhao; Jianmin, Yao; Xingqun, Zhang; Liang, Ma; Longchun, Zhang; Yibo, Xu; Peng, Wang; Zhen, Zhu

2015-11-01

To explore the clinical effect of the lobulated medial sural artery perforator flap in repairing soft tissue defect in hand or foot. Since March 2012 to September 2014, 6 cases with soft tissue defects in hands or feet were treated by lobulated medial sural artery flaps pedicled with 1st musculo-cutaneous perforator and 2st musculo-cutaneous perforator of the medial sural artery. The size of the flaps ranged from 4.5 cm x 10.0 cm to 6.0 cm x 17.0 cm. 5 cases of lobulated flap survived smoothly, only 1 lobulated flap had venous articulo, but this flap also survived after the articulo was removed by vascular exploration. All flaps had desirable appearance and sensation and the two-point discrimination was 6 mm in mean with 4 to 12 months follow-up (average, 7 months). Linear scar was left in donor sites in 3 cases and skin scar in 3 cases. There was no malfunction in donor sites. Lobulated medial sural artery perforator flap is feasible and ideal method for the treatment of soft tissue defect in hand or foot with satisfactory effect.

In Situ Splitting of a Rib Bone Graft for Reconstruction of Orbital Floor and Medial Wall.

PubMed

Uemura, Tetsuji; Yanai, Tetsu; Yasuta, Masato; Harada, Yoshimi; Morikawa, Aya; Watanabe, Hidetaka; Kurokawa, Masato

2017-06-01

In situ splitting of rib bone graft was conducted in 22 patients for the repair of orbital fracture with no other complicating fractures. A bone graft was harvested from the sixth or seventh rib in the right side. The repair of the orbital floor and medial wall was successful in all the cases. Ten patients had bone grafting to the orbital floor, eight had it done onto medial wall, and 4 onto both floor and wall after reduction. The mean length of in situ rib bone graft was 40.9 mm (range, 20-70 mm), the mean width of these was 14.9 mm (range, 8-20 mm). The bone grafting was done by one leaf for 15 cases and two leafs for 7 cases in size of defects. The technique of in situ splitting of a rib bone graft for the repair of the orbital floor and medial wall is a simple and safe procedure, easily taking out the in situ splitting of a rib, and less pain in donor site. It has proved to be an optimal choice in craniofacial reconstruction, especially the defects of orbital floor and medial wall.

Large meniscus extrusion ratio is a poor prognostic factor of conservative treatment for medial meniscus posterior root tear.

PubMed

Kwak, Yoon-Ho; Lee, Sahnghoon; Lee, Myung Chul; Han, Hyuk-Soo

2018-03-01

The purpose of this study was to find a prognostic factor of medial meniscus posterior root tear (MMPRT) for surgical decision making. Eighty-eight patients who were diagnosed as acute or subacute MMPRT without severe degeneration of the meniscus were treated conservatively for 3 months. Fifty-seven patients with MMPRT showed good response to conservative treatment (group 1), while the remaining 31 patients who failed to conservative treatment (group 2) received arthroscopic meniscus repair. Their demographic characteristics and radiographic features including hip-knee-ankle angle, joint line convergence angle, Kellgren-Lawrence grade in plain radiographs, meniscus extrusion (ME) ratio (ME-medial femoral condyle ratio, ME-medial tibial plateau ratio, ME-meniscus width ratio), the location of bony edema, and cartilage lesions in MRI were compared. Receiver operating characteristic (ROC) curve analysis was also performed to determine the cut-off values of risk factors. The degree of ME-medial femoral condyle and medial tibia plateau ratio of group 2 was significantly higher than group 1 (0.08 and 0.07 vs. 0.1 and 0.09, respectively, both p < 0.001). No significant (n.s.) difference in other variables was found between the two groups. On ROC curve analysis, ME-medial femoral condyle ratio was confirmed as the most reliable prognostic factor of conservative treatment for MMPRT (area under ROC = 0.8). The large meniscus extrusion ratio was the most reliable poor prognostic factor of conservative treatment for MMPRT. Therefore, for MMPRT patients with large meniscus extrusion, early surgical repair could be considered as the primary treatment option. III.

Theta Synchronizes the Activity of Medial Prefrontal Neurons during Learning

ERIC Educational Resources Information Center

Paz, Rony; Bauer, Elizabeth P.; Pare, Denis

2008-01-01

Memory consolidation is thought to involve the gradual transfer of transient hippocampal-dependent traces to distributed neocortical sites via the rhinal cortices. Recently, medial prefrontal (mPFC) neurons were shown to facilitate this process when their activity becomes synchronized. However, the mechanisms underlying this enhanced synchrony…

Metal-mediated DNA base pairing: alternatives to hydrogen-bonded Watson-Crick base pairs.

PubMed

Takezawa, Yusuke; Shionoya, Mitsuhiko

2012-12-18

With its capacity to store and transfer the genetic information within a sequence of monomers, DNA forms its central role in chemical evolution through replication and amplification. This elegant behavior is largely based on highly specific molecular recognition between nucleobases through the specific hydrogen bonds in the Watson-Crick base pairing system. While the native base pairs have been amazingly sophisticated through the long history of evolution, synthetic chemists have devoted considerable efforts to create alternative base pairing systems in recent decades. Most of these new systems were designed based on the shape complementarity of the pairs or the rearrangement of hydrogen-bonding patterns. We wondered whether metal coordination could serve as an alternative driving force for DNA base pairing and why hydrogen bonding was selected on Earth in the course of molecular evolution. Therefore, we envisioned an alternative design strategy: we replaced hydrogen bonding with another important scheme in biological systems, metal-coordination bonding. In this Account, we provide an overview of the chemistry of metal-mediated base pairing including basic concepts, molecular design, characteristic structures and properties, and possible applications of DNA-based molecular systems. We describe several examples of artificial metal-mediated base pairs, such as Cu(2+)-mediated hydroxypyridone base pair, H-Cu(2+)-H (where H denotes a hydroxypyridone-bearing nucleoside), developed by us and other researchers. To design the metallo-base pairs we carefully chose appropriate combinations of ligand-bearing nucleosides and metal ions. As expected from their stronger bonding through metal coordination, DNA duplexes possessing metallo-base pairs exhibited higher thermal stability than natural hydrogen-bonded DNAs. Furthermore, we could also use metal-mediated base pairs to construct or induce other high-order structures. These features could lead to metal-responsive functional

Ultrasonography of the medial iliac lymph nodes in the dog.

PubMed

Llabrés-Díaz, Francisco J

2004-01-01

Sixty-one medial iliac lymph nodes of 38 different dogs (eight with adenocarcinoma of the apocrine glands of the anal sac, 13 with multicentric lymphoma, six with multicentric lymphoma but in clinical remission, and 11 control dogs) were evaluated to assess the ability of ultrasound to identify and interrogate these lymph nodes across the different groups and to differentiate these groups using different sonographic parameters. Ultrasound proved to be useful to assess canine medial iliac lymph nodes. An increase in size or number of detected lymph nodes or finding rounder or heterogeneous lymph nodes could differentiate lymph nodes of dogs of the control group from lymph nodes of dogs with lymphoma or an adenocarcinoma of the apocrine glands of the anal sac. Subcategories of malignancy could not be differentiated. More studies need to be performed, both with patients with reactive lymph nodes and also focusing on other canine superficial lymph nodes, before generalizing the results of this study to other areas or diseases.

Inactivating the infralimbic but not prelimbic medial prefrontal cortex facilitates the extinction of appetitive Pavlovian conditioning in Long-Evans rats.

PubMed

Mendoza, J; Sanio, C; Chaudhri, N

2015-02-01

The infralimbic medial prefrontal cortex (IL) has been posited as a common node in distinct neural circuits that mediate the extinction of appetitive and aversive conditioning. However, appetitive extinction is typically assessed using instrumental conditioning procedures, whereas the extinction of aversive conditioning is customarily studied using Pavlovian assays. The role of the IL in the extinction of appetitive Pavlovian conditioning remains underexplored. We investigated the involvement of the IL and prelimbic medial prefrontal cortex (PrL) in appetitive extinction in Pavlovian and instrumental conditioning assays in male, Long-Evans rats. Following acquisition, a gamma-aminobutyric acid agonist solution (0.03 nmol muscimol; 0.3 nmol baclofen; 0.3 μl/side) was bilaterally microinfused into the IL or PrL to pharmacologically inactivate each region before the first extinction session. Compared to saline, PrL inactivation did not affect the acquisition of extinction or the recall of extinction memory 24-h later. IL inactivation caused a more rapid extinction of Pavlovian conditioning, but had no effect on the extinction of instrumental conditioning or extinction recall. IL inactivation during a Pavlovian conditioning session in which conditioned stimulus (CS) trials were paired with sucrose did not affect CS-elicited behaviour, but increased responding during intervals that did not contain the CS. The same manipulation did not impact lever pressing for sucrose. These findings suggest that the IL may normally maintain Pavlovian conditioned responding when an anticipated appetitive CS is unexpectedly withheld, and that this region has distinct roles in the expression of Pavlovian conditioning when an appetitive unconditioned stimulus is either presented or omitted. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparison of neuromuscular and quadriceps strengthening exercise in the treatment of varus malaligned knees with medial knee osteoarthritis: a randomised controlled trial protocol.

PubMed

Bennell, Kim L; Egerton, Thorlene; Wrigley, Tim V; Hodges, Paul W; Hunt, Michael; Roos, Ewa M; Kyriakides, Mary; Metcalf, Ben; Forbes, Andrew; Ageberg, Eva; Hinman, Rana S

2011-12-05

Osteoarthritis of the knee involving predominantly the medial tibiofemoral compartment is common in older people, giving rise to pain and loss of function. Many people experience progressive worsening of the disease over time, particularly those with varus malalignment and increased medial knee joint load. Therefore, interventions that can reduce excessive medial knee loading may be beneficial in reducing the risk of structural progression. Traditional quadriceps strengthening can improve pain and function in people with knee osteoarthritis but does not appear to reduce medial knee load. A neuromuscular exercise program, emphasising optimal alignment of the trunk and lower limb joints relative to one another, as well as quality of movement performance, while dynamically and functionally strengthening the lower limb muscles, may be able to reduce medial knee load. Such a program may also be superior to traditional quadriceps strengthening with respect to improved pain and physical function because of the functional and dynamic nature. This randomised controlled trial will investigate the effect of a neuromuscular exercise program on medial knee joint loading, pain and function in individuals with medial knee joint osteoarthritis. We hypothesise that the neuromuscular program will reduce medial knee load as well as pain and functional limitations to a greater extent than a traditional quadriceps strengthening program. 100 people with medial knee pain, radiographic medial compartment osteoarthritis and varus malalignment will be recruited and randomly allocated to one of two 12-week exercise programs: quadriceps strengthening or neuromuscular exercise. Each program will involve 14 supervised exercise sessions with a physiotherapist plus four unsupervised sessions per week at home. The primary outcomes are medial knee load during walking (the peak external knee adduction moment from 3D gait analysis), pain, and self-reported physical function measured at baseline and

Comparison of neuromuscular and quadriceps strengthening exercise in the treatment of varus malaligned knees with medial knee osteoarthritis: a randomised controlled trial protocol

PubMed Central

2011-01-01

Background Osteoarthritis of the knee involving predominantly the medial tibiofemoral compartment is common in older people, giving rise to pain and loss of function. Many people experience progressive worsening of the disease over time, particularly those with varus malalignment and increased medial knee joint load. Therefore, interventions that can reduce excessive medial knee loading may be beneficial in reducing the risk of structural progression. Traditional quadriceps strengthening can improve pain and function in people with knee osteoarthritis but does not appear to reduce medial knee load. A neuromuscular exercise program, emphasising optimal alignment of the trunk and lower limb joints relative to one another, as well as quality of movement performance, while dynamically and functionally strengthening the lower limb muscles, may be able to reduce medial knee load. Such a program may also be superior to traditional quadriceps strengthening with respect to improved pain and physical function because of the functional and dynamic nature. This randomised controlled trial will investigate the effect of a neuromuscular exercise program on medial knee joint loading, pain and function in individuals with medial knee joint osteoarthritis. We hypothesise that the neuromuscular program will reduce medial knee load as well as pain and functional limitations to a greater extent than a traditional quadriceps strengthening program. Methods/Design 100 people with medial knee pain, radiographic medial compartment osteoarthritis and varus malalignment will be recruited and randomly allocated to one of two 12-week exercise programs: quadriceps strengthening or neuromuscular exercise. Each program will involve 14 supervised exercise sessions with a physiotherapist plus four unsupervised sessions per week at home. The primary outcomes are medial knee load during walking (the peak external knee adduction moment from 3D gait analysis), pain, and self-reported physical function

Utility of nerve conduction studies for diagnosis of injury to the medial branch of the superficial radial nerve.

PubMed

Kon, Tomoya; Suzuki, Chieko; Hotta, Ryotaro; Funamizu, Yukihisa; Haga, Rie; Ueno, Tatsuya; Nishijima, Haruo; Arai, Akira; Nunomura, Jinichi; Nukada, Hitoshi; Tomiyama, Masahiko; Baba, Masayuki

2017-09-01

The clinical utility of nerve conduction study (NCS) for the distal medial branch of the superficial radial nerve (SRN) has not yet been clarified. Therefore, we investigated the clinical utility of NCS in patients with suspected SRN injury and compared the results with those in healthy control subjects. Bilateral NCS of the medial branch of the SRN was performed in two patients with suspected injury of the medial branch of the SRN, and in 20 healthy control subjects. A surface recording electrode was placed at the medial side of the metacarpophalangeal joint of the thumb. The SRN was then stimulated at a location 12 cm proximal from the recording electrode. The mean sensory nerve action potential in the two patients was significantly lower than that of the controls (6.75 ± 0.92 vs. 23.8 ± 8.2 μV, P  < 0.05). The side-to-side differences in sensory nerve action potential in the two patients were significantly higher than in the controls (55 ± 7.1 vs. 11 ± 7.8%, P  < 0.05). NCS may be useful for diagnosing injury of the medial branch of the SRN.

Semimembranosus Release for Medial Soft Tissue Balancing Does Not Weaken Knee Flexion Strength in Patients Undergoing Varus Total Knee Arthroplasty.

PubMed

Jang, Sung Won; Koh, In Jun; Kim, Man Soo; Kim, Ju Yeong; In, Yong

2016-11-01

The sequential medial release technique including semimembranosus (semiM) release is effective and safe during varus total knee arthroplasty (TKA). However, there are concerns about weakening of knee flexion strength after semiM release. We determined whether semiM release to balance the medial soft tissue decreased knee flexion strength after TKA. Fifty-nine consecutive varus knees undergoing TKA were prospectively enrolled. A 3-step sequential release protocol which consisted of release of (1) the deep medial collateral ligament (dMCL), (2) the semiM, and (3) the superficial medial collateral ligament based on medial tightness. Gap balancing was obtained after dMCL release in 31 knees. However, 28 knees required semiM release or more after dMCL release. Isometric muscle strength of the knee was compared 6 months postoperatively between the semiM release and semiM nonrelease groups. Knee stability and clinical outcomes were also compared. No differences in knee flexor or extensor peak torque were observed between the groups 6 months postoperatively (P = .322 and P = .383, respectively). No group difference was observed in medial joint opening angle on valgus stress radiographs (P = .327). No differences in the Knee Society or Western Ontario and McMaster Universities Osteoarthritis Index scores were detected between the groups (P = .840 and P = .682, respectively). These results demonstrate that semiM release as a sequential step to balance medial soft tissue in varus knees did not affect knee flexion strength after TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

Cooper Pairs in Insulators?!

ScienceCinema

James Valles

2017-12-09

Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

A Bony Landmark 'RAI Triangle' to Prevent 'Misplaced and Misdirected' Medial Cut in SSRO.

PubMed

Rai, Kirthi Kumar; Arakeri, Gururaj; Khaji, Shahanavaj I

2011-03-01

'Rai triangle', a new anatomic landmark on the medial surface of the ramus of the mandible which when identified and taken into consideration, may have a definite advantage. This is especially in terms of performing the medial horizontal cut which is an important and integral part of the sagittal split ramus osteotomy so as to avoid a bad split. The objective of this article is to propose an easily identifiable bony land mark, which is closely related to lingula of mandible that may ease the procedure of osteotomy and avoid bad splits.

Introducing a model of pairing based on base pair specific interactions between identical DNA sequences

NASA Astrophysics Data System (ADS)

(O' Lee, Dominic J.

2018-02-01

At present, there have been suggested two types of physical mechanism that may facilitate preferential pairing between DNA molecules, with identical or similar base pair texts, without separation of base pairs. One mechanism solely relies on base pair specific patterns of helix distortion being the same on the two molecules, discussed extensively in the past. The other mechanism proposes that there are preferential interactions between base pairs of the same composition. We introduce a model, built on this second mechanism, where both thermal stretching and twisting fluctuations are included, as well as the base pair specific helix distortions. Firstly, we consider an approximation for weak pairing interactions, or short molecules. This yields a dependence of the energy on the square root of the molecular length, which could explain recent experimental data. However, analysis suggests that this approximation is no longer valid at large DNA lengths. In a second approximation, for long molecules, we define two adaptation lengths for twisting and stretching, over which the pairing interaction can limit the accumulation of helix disorder. When the pairing interaction is sufficiently strong, both adaptation lengths are finite; however, as we reduce pairing strength, the stretching adaptation length remains finite but the torsional one becomes infinite. This second state persists to arbitrarily weak values of the pairing strength; suggesting that, if the molecules are long enough, the pairing energy scales as length. To probe differences between the two pairing mechanisms, we also construct a model of similar form. However, now, pairing between identical sequences solely relies on the intrinsic helix distortion patterns. Between the two models, we see interesting qualitative differences. We discuss our findings, and suggest new work to distinguish between the two mechanisms.

New Semantic Learning in Patients With Large Medial Temporal Lobe Lesions

PubMed Central

Bayley, P.J.; O'Reilly, R.C.; Curran, T.; Squire, L.R.

2008-01-01

Two patients with large lesions of the medial temporal lobe were given four tests of semantic knowledge that could only have been acquired after the onset of their amnesia. In contrast to previous studies of postmorbid semantic learning, correct answers could be based on a simple, nonspecific sense of familiarity about single words, faces, or objects. According to recent computational models (for example, Norman and O'Reilly (2003) Psychol Rev 110:611–646), this characteristic should be optimal for detecting the kind of semantic learning that might be supported directly by the neocortex. Both patients exhibited some capacity for new learning, albeit at a level substantially below control performances. Notably, the correct answers appeared to reflect declarative memory. It was not the case that the correct answers simply popped out in some automatic way in the absence of any additional knowledge about the items. Rather, the few correct choices made by the patients tended to be accompanied by additional information about the chosen items, and the available knowledge appeared to be similar qualitatively to the kind of factual knowledge that healthy individuals gradually acquire over the years. The results are consistent with the idea that neocortical structures outside the medial temporal lobe are able to support some semantic learning, albeit to a very limited extent. Alternatively, the small amount of learning detected in the present study could depend on tissue within the posterior medial temporal lobe that remains intact in both patients. PMID:18306299

Epileptic phenotype of FGFR3-related bilateral medial temporal lobe dysgenesis.

PubMed

Okazaki, Tetsuya; Saito, Yoshiaki; Ueda, Riyo; Awashima, Takeya; Nishimura, Yoko; Yuasa, Isao; Shinohara, Yuki; Adachi, Kaori; Sasaki, Masayuki; Nanba, Eiji; Maegaki, Yoshihiro

2017-01-01

Hypochondroplasia (HCH) is a skeletal dysplasia, characterized by short stature and macrocephaly. Clinical symptoms and radiological and histopathological features of HCH are similar, but milder than those seen in achondroplasia. Particularly, HCH patients with Asn540Lys mutation in the FGFR3 gene are reported to have medial temporal lobe dysgenesis and epilepsy. We report a 3-year-old girl who developed recurrent epileptic apnea, which started immediately after birth. The apneic seizures were refractory to antiepileptic medications; ictal electroencephalography showed rhythmic activity originating from the left or right temporal areas and rarely from the right frontal area. Macrocephaly was noted since birth. Neuroimaging revealed bilateral dysgenesis and hypometabolism of the medial temporal structures as well as perfusion changes in the left lateral temporofrontal areas during the ictal period. Clonazepam was initiated and acetazolamide dosage was increased at 6months, resulting in complete seizure control after 8months of age. Genetic analysis identified an Asn540Lys (c.1620 C>A) mutation in the FGFR3 gene. Characteristic bone findings on the lumbar spine, iliac bone, and femur were retrospectively confirmed on X-rays during infancy. This was the first report that delineated the epilepsy phenotype in FGFR3-related bilateral medial temporal lobe dysgenesis; such findings would lead to an early diagnosis and better epilepsy management. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Effect of medial arch-heel support in inserts on reducing ankle eversion: a biomechanics study

PubMed Central

Fong, Daniel TP; Lam, Mak-Ham; Lao, Miko LM; Chan, Chad WN; Yung, Patrick SH; Fung, Kwai-Yau; Lui, Pauline PY; Chan, Kai-Ming

2008-01-01

Background Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running. Methods Thirteen pronators and 13 normal subjects participated in standing, walking and running trials in each of the following conditions: (1) barefoot, and shod condition with insert with (2) no, (3) low, (4) medium, and (5) high medial arch-heel support. Motions were captured and processed by an eight-camera motion capture system. Maximum ankle eversion was calculated by incorporating the raw coordinates of 15 anatomical positions to a self-compiled Matlab program with kinematics equations. Analysis of variance with repeated measures with post-hoc Tukey pairwise comparisons was performed on the data among the five walking conditions and the five running conditions separately. Results Results showed that the inserts with medial arch-heel support were effective in dynamics trials but not static trials. In walking, they successfully reduced the maximum eversion by 2.1 degrees in normal subjects and by 2.5–3.0 degrees in pronators. In running, the insert with low medial arch support significantly reduced maximum eversion angle by 3.6 and 3.1 degrees in normal subjects and pronators respectively. Conclusion Medial arch-heel support in inserts is effective in reducing ankle eversion in walking and running, but not in standing. In walking, there is a trend to bring the over-pronated feet of the pronators back to the normal eversion range. In running, it shows an effect to restore normal eversion range in 84% of the pronators. PMID:18289375

Congruence and joint space width alterations of the medial compartment following lateral unicompartmental knee arthroplasty.

PubMed

Zuiderbaan, H A; Khamaisy, S; Thein, R; Nawabi, D H; Pearle, A D

2015-01-01

Progressive degenerative changes in the medial compartment of the knee following lateral unicompartmental arthroplasty (UKA) remains a leading indication for revision surgery. The purpose of this study is to evaluate changes in the congruence and joint space width (JSW) of the medial compartment following lateral UKA. The congruence of the medial compartment of 53 knees (24 men, 23 women, mean age 13.1 years; sd 62.1) following lateral UKA was evaluated pre-operatively and six weeks post-operatively, and compared with 41 normal knees (26 men, 15 women, mean age 33.7 years; sd 6.4), using an Interactive closest point algorithm which calculated the congruence index (CI) by performing a rigid transformation that best aligns the digitised tibial and femoral surfaces. Inner, middle and outer JSWs were measured by sub-dividing the medial compartment into four quarters on pre- and post-operative, weight bearing tunnel view radiographs. The mean CI of knees following lateral UKA significantly improved from 0.92 (sd 0.06) pre-operatively to 0.96 (sd 0.02) (p < 0.001) six weeks post-operatively. The mean CI of the healthy control group was 0.99 sd 0.01. Post-operatively, the mean inner JSW increased (p = 0.006) and the outer decreased (p = 0.002). The JSW was restored post-operatively as no significant differences were noted in all three locations compared with the control group (inner JSW p = 0.43; middle JSW p = 0.019, outer JSW p = 0.51). Our data suggest that a well conducted lateral UKA may improve the congruence and normalise the JSW of the medial compartment, potentially preventing progression of degenerative change. ©2015 The British Editorial Society of Bone & Joint Surgery.

Content-Specific Source Encoding in the Human Medial Temporal Lobe

ERIC Educational Resources Information Center

Awipi, T.; Davachi, L.

2008-01-01

Although the medial temporal lobe (MTL) is known to be essential for episodic encoding, the contributions of individual MTL subregions remain unclear. Data from recognition memory studies have provided evidence that the hippocampus supports relational encoding important for later episodic recollection, whereas the perirhinal cortex has been linked…

Estrogen receptor-a in medial amygdala neurons regulates body weight

USDA-ARS?s Scientific Manuscript database

Estrogen receptor–a (ERa) activity in the brain prevents obesity in both males and females. However, the ERa-expressing neural populations that regulate body weight remain to be fully elucidated. Here we showed that single-minded–1 (SIM1) neurons in the medial amygdala (MeA) express abundant levels ...

Role of ventral medial prefrontal cortex in incubation of cocaine craving

PubMed Central

Koya, Eisuke; Uejima, Jamie L.; Wihbey, Kristina A.; Bossert, Jennifer M.; Hope, Bruce T.; Shaham, Yavin

2009-01-01

Cue-induced drug-seeking in rodents progressively increases after withdrawal from cocaine, suggesting that cue-induced cocaine craving incubates over time. Here, we explored the role of the medial prefrontal cortex (mPFC, a brain area previously implicated in cue-induced cocaine seeking) in this incubation. We trained rats to self-administer cocaine for 10 d (6 h/d, infusions were paired with a tone-light cue), and then assessed after 1 or 30 withdrawal days the effect of exposure to cocaine cues on lever presses in extinction tests. We found that cue-induced cocaine-seeking in the extinction tests was higher after 30 withdrawal days than after 1 day. The time-dependent increases in extinction responding were associated with large (ventral mPFC) or modest (dorsal mPFC) increases in ERK phosphorylation (a measure of ERK activity and an index of neuronal activation). After 30 withdrawal days, ventral but not dorsal injections of muscimol+baclofen (GABAa+GABAb receptor agonists that inhibit neuronal activity) decreased extinction responding. After 1 withdrawal day, ventral but not dorsal mPFC injections of bicuculline+saclofen (GABAa+GABAb receptor antagonists that increase neuronal activity) strongly increased extinction responding. Finally, muscimol+baclofen had minimal effect on extinction responding after 1 day, and in cocaine-experienced rats, ventral mPFC injections of muscimol+baclofen or bicuculline+saclofen had no effect on lever presses for an oral sucrose solution. The present results indicate that ventral mPFC neuronal activity plays an important role in the incubation of cocaine craving. PMID:18565549

Monoplanar versus biplanar medial open-wedge proximal tibial osteotomy for varus gonarthrosis: a comparison of clinical and radiological outcomes.

PubMed

Elmalı, Nurzat; Esenkaya, Irfan; Can, Murat; Karakaplan, Mustafa

2013-12-01

We compared clinical and radiological results of two proximal tibial osteotomy (PTO) techniques: monoplanar medial open-wedge osteotomy and biplanar retrotubercle medial open-wedge osteotomy, stabilised by a wedged plate. We evaluated 88 knees in 78 patients. Monoplanar medial open-wedge PTO was performed on 56 knees in 50 patients with a mean age of 55 ± 9 years. Biplanar retrotubercle medial open-wedge PTO was performed on 32 knees in 28 patients with a mean age of 57 ± 7 years. Mean follow-up periods were 40.6 ± 7 months for the monoplanar PTO group and 38 ± 5 months for the biplanar retrotubercle PTO group. Clinical outcome was evaluated using the hospital for special surgery scoring system, and radiological outcome was evaluated by the measurements of femorotibial angle (FTA), patellar height and tibial slope changes. In both groups, post-operative HSS scores increased significantly. No significant difference was found between groups in FTA alteration, but the FTA decreased significantly in both groups. Patellar index ratios decreased significantly in the monoplanar PTO group (Insall-Salvati Index by 0.07, Blackburne-Peel Index by 0.07), but not in the biplanar retrotubercle PTO group. Tibial slopes were increased significantly in the monoplanar PTO group, but not in the retrotubercle PTO group. Biplanar retrotubercle medial open-wedge osteotomy and monoplanar medial open-wedge osteotomy are both clinically effective for the treatment for varus gonarthrosis. Retrotubercle osteotomy also prevents patella infera and tibial slope changes radiologically.

Somitic origin of the medial border of the mammalian scapula and its homology to the avian scapula blade.

PubMed

Valasek, Petr; Theis, Susanne; Krejci, Eliska; Grim, Milos; Maina, Flavio; Shwartz, Yulia; Otto, Anthony; Huang, Ruijin; Patel, Ketan

2010-04-01

The scapula is the main skeletal element of the pectoral girdle allowing muscular fixation of the forelimb to the axial skeleton. The vertebrate limb skeleton has traditionally been considered to develop from the lateral plate mesoderm, whereas the musculature originates from the axial somites. However, in birds, the scapular blade has been shown to develop from the somites. We investigated whether a somitic contribution was also present in the mammalian scapula. Using genetic lineage-tracing techniques, we show that the medial border of the mammalian scapula develops from somitic cells. The medial scapula border serves as the attachment site of girdle muscles (serratus anterior, rhomboidei and levator scapulae). We show that the development of these muscles is independent of the mechanism that controls the formation of all other limb muscles. We suggest that these muscles be specifically referred to as medial girdle muscles. Our results establish the avian scapular blade and medial border of the mammalian scapula as homologous structures as they share the same developmental origin.

Vortex pairs on surfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koiller, Jair; Boatto, Stefanella

2009-05-06

A pair of infinitesimally close opposite vortices moving on a curved surface moves along a geodesic, according to a conjecture by Kimura. We outline a proof. Numerical simulations are presented for a pair of opposite vortices at a close but nonzero distance on a surface of revolution, the catenoid. We conjecture that the vortex pair system on a triaxial ellipsoid is a KAM perturbation of Jacobi's geodesic problem. We outline some preliminary calculations required for this study. Finding the surfaces for which the vortex pair system is integrable is in order.

Matrix metalloprotease-3 expression in the medial plica and pannus-like tissue in knees from patients with medial compartment osteoarthritis.

PubMed

Wang, Hwai-Shi; Kuo, Pei-Yin; Yang, Chih-Chang; Lyu, Shaw-Ruey

2011-03-01

The severity of cartilage degeneration is positively correlated with the severity of the pathologic change of medial plica. However, knowledge of the pathogenic mechanisms and the impact of plica on cartilage destruction is limited. The aim of the present study was therefore to investigate matrix metalloprotease-3 (MMP-3) expression in the plica isolated from patients with medial compartment osteoarthritis of the knee. Immunohistochemistry showed that MMP-3 was highly expressed in pannus-like tissue and the plica. Western blotting of culture supernatants showed that interleukin-1β (IL-1β) treatment induced MMP-3 release by cells isolated from pannus tissue or the plica. Furthermore, reverse transcriptase polymerase chain reaction and real-time polymerase chain reaction analysis showed that MMP-3 mRNA levels were increased after IL-1β treatment of the cultured cells. MMP-3 and IL-1β mRNAs were expressed in the plica and pannus-like tissue, with MMP-3 mRNA being expressed at significantly higher levels in the plica than in normal synovial membrane and highly expressed in the plica at different stages in osteoarthritis (OA) patients. Pannus-like tissue and the plica express IL-1β and MMP-3. Moreover, MMP-3 mRNA and protein expression in the plica may contribute to the pathogenesis of OA. © 2011 Blackwell Publishing Limited.

Design of push-pull system to control diesel particular matter inside a dead-end entry.

PubMed

Zheng, Yi; Thiruvengadam, Magesh; Lan, Hai; Tien, Jerry C

Diesel particulate matter (DPM) is considered to be carcinogenic after prolonged exposure. With more diesel-powered equipment used in underground mines, miners' exposure to DPM has become an increasing concern. This paper used computational fluid dynamics method to study the DPM dispersion in a dead-end entry with loading operation. The effects of different push-pull ventilation systems on DPM distribution were evaluated to improve the working conditions for underground miners. The four push-pull systems considered include: long push and short pull tubing; short push and long pull tubing, long push and curved pull tubing, and short push and curved pull tubing. A species transport model with buoyancy effect was used to examine the DPM dispersion pattern with unsteady state analysis. During the 200 s of loading operation, high DPM levels were identified in the face and dead-end entry regions. This study can be used for mining engineer as guidance to design and setup local ventilation, select DPM control strategies and for DPM annual training for underground miners.

Diesel exhaust particulate material expression of in vitro genotoxic activities when dispersed into a phospholipid component of lung surfactant

NASA Astrophysics Data System (ADS)

Shi, X. C.; Keane, M. J.; Ong, T. M.; Harrison, J. C.; Slaven, J. E.; Bugarski, A. D.; Gautam, M.; Wallace, W. E.

2009-02-01

Bacterial mutagenicity and mammalian cell chromosomal and DNA damage in vitro assays were performed on a diesel exhaust particulate material (DPM) standard in two preparations: as an organic solvent extract, and as an aqueous dispersion in a simulated pulmonary surfactant. U.S. National Institute for Standards and Technology DPM SRM 2975 expressed mutagenic activity in the Salmonella reversion assay, and for in vitro genotoxicity to mammalian cells as micronucleus induction and as DNA damage in both preparations: as an acetone extract of the DPM mixed into dimethylsulfoxide, and as a mixture of whole DPM in a dispersion of dipalmitoyl phosphatidyl choline. Dispersion in surfactant was used to model the conditioning of DPM depositing on the deep respiratory airways of the lung. DPM solid residue after acetone extraction was inactive when assayed as a surfactant dispersion in the micronucleus induction assay, as was surfactant dispersion of a respirable particulate carbon black. In general, a given mass of the DPM in surfactant dispersion expressed greater activity than the solvent extract of an equal mass of DPM.

Threat-Detection and Attentional Bias to Threat in Women Recovered from Anorexia Nervosa: Neural Alterations in Extrastriate and Medial Prefrontal Cortices.

PubMed

Bang, Lasse; Rø, Øyvind; Endestad, Tor

2017-03-01

Behavioral studies have shown that anorexia nervosa (AN) is associated with attentional bias to general threat cues. The neurobiological underpinnings of attentional bias to threat in AN are unknown. This study investigated the neural responses associated with threat-detection and attentional bias to threat in AN. We measured neural responses to a dot-probe task, involving pairs of angry and neutral face stimuli, in 22 adult women recovered from AN and 21 comparison women. Recovered AN women did not exhibit a behavioral attentional bias to threat. In response to angry faces, recovered women showed significant hypoactivation in the extrastriate cortex. During attentional bias to angry faces, recovered women showed significant hyperactivation in the medial prefrontal cortex. This was because of significant deactivation in comparison women, which was absent in recovered AN women. Women recovered from AN are characterized by altered neural responses to threat cues. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

Medial unicompartmental knee arthroplasty improves congruence and restores joint space width of the lateral compartment.

PubMed

Khamaisy, Saker; Zuiderbaan, Hendrik A; van der List, Jelle P; Nam, Denis; Pearle, Andrew D

2016-06-01

Osteoarthritic progression of the lateral compartment remains a leading indication for medial unicompartmental knee arthroplasty (UKA) revision. Therefore, the purpose of this study was to evaluate the alterations of the lateral compartment congruence and joint space width (JSW) following medial UKA. Retrospectively, lateral compartment congruence and JSW were evaluated in 174 knees (74 females, 85 males, mean age 65.5years; SD±10.1) preoperatively and six weeks postoperatively, and compared to 41 healthy knees (26 men, 15 women, mean age 33.7years; SD±6.4). Congruence (CI) was calculated using validated software that evaluates the geometric relationship between surfaces and calculates a congruence index (CI). JSW was measured on three sides (inner, middle, outer) by subdividing the lateral compartment into four quarters. The CI of the control group was 0.98 (SD±0.01). The preoperative CI was 0.88 (SD±0.01), which improved significantly to 0.93 (SD±0.03) postoperatively (p<0.001). In 82% of knees, CI improved after surgery, while in 18% it decreased. The preoperative significant JSW differences of the inner (p<0.001) and outer JSW (p<0.001) were absent postoperatively. Our data suggests that a well-conducted medial UKA not only resurfaces the medial compartment but also improves congruence and restores the JSW of the lateral compartment. Copyright © 2016 Elsevier B.V. All rights reserved.

Mobile-bearing medial unicompartmental knee arthroplasty restores limb alignment comparable to that of the unaffected contralateral limb

PubMed Central

Mullaji, Arun B; Shah, Siddharth; Shetty, Gautam M

2017-01-01

Background and purpose — Medial unicompartmental knee arthroplasty (UKA) is undertaken in patients with a passively correctable varus deformity. We investigated whether restoration of natural soft tissue tension would result in a lower limb alignment similar to that of the contralateral unaffected lower limb after mobile-bearing medial UKA. Patients and methods — In this retrospective study, hip-knee-ankle (HKA) angle, position of the weight-bearing axis (WBA), and knee joint line obliquity (KJLO) after mobile-bearing medial UKA was compared with that of the unaffected (clinically and radiologically) contralateral lower limb in 123 patients. Results — Postoperatively, HKA angle was restored to within ±3° of the contralateral lower limb in 87% of the patients and the WBA passed within ±1 Kennedy and White’s tibial zone of the unaffected contralateral lower limb in 95% of the patients. The mean KJLO in the operated limbs was not significantly different from that in the unaffected lower limbs (p = 0.07) and the KJLO in the operated limb was restored to within ±3° of that in the contralateral lower limb in 96% of the patients. Interpretation — Lower limb alignment and knee joint line obliquity after mobile-bearing medial UKA were comparable to that of the unaffected contralateral limb in most patients. Comparison with the contralateral unaffected lower limb is a reliable method for evaluation and validation of limb mechanical alignment after mobile-bearing medial UKA. PMID:27794622

Effect of Pulsed Radiofrequency Treatment on the Thoracic Medial Branch for Managing Chronic Thoracic Facet Joint Pain Refractory to Medial Branch Block with Local Anesthetics.

PubMed

Chang, Min Cheol

2018-03-01

To evaluate the effect of pulsed radiofrequency (PRF) stimulation of the thoracic medial branch of the dorsal ramus in patients with chronic thoracic facet joint (TFJ) pain who were refractory to medial branch block (MBB). This was a prospective, observational study. The author retrospectively reviewed data from 72 patients who had received therapeutic MBB with 0.5 mL of 2% lidocaine mixed with 0.5 mL of 0.25% bupivacaine to treat TFJ-origin upper or midback pain. Of these patients, 20 were included to evaluate the effects of PRF on the thoracic medical branch to manage TFJ pain refractory to therapeutic MBB. PRF stimulation was administered at 5 Hz and a 5-millisecond pulsed width for 360 seconds at 45 V. The pain-reducing effect of the PRF procedure was evaluated via the numeric rating scale (NRS) at 1, 2, and 3 months after treatment. Successful pain relief was defined as ≥50% reduction in the NRS score compared with the score before treatment. The NRS scores changed significantly over time (pretreatment, 6.0 ± 1.0; 1 month, 3.3 ± 2.2; 2 months, 3.9 ± 2.1; and 3 months, 4.0 ± 2.2). At 1, 2, and 3 months after the PRF procedure, the NRS scores were significantly reduced compared with the scores before the treatment. Eleven (55%) of 20 patients reported successful pain relief at 3 months after PRF. The author suggests that PRF on the thoracic medial branch is an effective and safe interventional technique for the control of chronic TFJ pain. Copyright © 2017 Elsevier Inc. All rights reserved.

A central mesencephalic reticular formation projection to medial rectus motoneurons supplying singly and multiply innervated extraocular muscle fibers.

PubMed

Bohlen, Martin O; Warren, Susan; May, Paul J

2017-06-01

We recently demonstrated a bilateral projection to the supraoculomotor area from the central mesencephalic reticular formation (cMRF), a region implicated in horizontal gaze changes. C-group motoneurons, which supply multiply innervated fibers in the medial rectus muscle, are located within the primate supraoculomotor area, but their inputs and function are poorly understood. Here, we tested whether C-group motoneurons in Macaca fascicularis monkeys receive a direct cMRF input by injecting this portion of the reticular formation with anterograde tracers in combination with injection of retrograde tracer into the medial rectus muscle. The results indicate that the cMRF provides a dense, bilateral projection to the region of the medial rectus C-group motoneurons. Numerous close associations between labeled terminals and each multiply innervated fiber motoneuron were present. Within the oculomotor nucleus, a much sparser ipsilateral projection onto some of the A- and B- group medial rectus motoneurons that supply singly innervated fibers was observed. Ultrastructural analysis demonstrated a direct synaptic linkage between anterogradely labeled reticular terminals and retrogradely labeled medial rectus motoneurons in all three groups. These findings reinforce the notion that the cMRF is a critical hub for oculomotility by proving that it contains premotor neurons supplying horizontal extraocular muscle motoneurons. The differences between the cMRF input patterns for C-group versus A- and B-group motoneurons suggest the C-group motoneurons serve a different oculomotor role than the others. The similar patterns of cMRF input to C-group motoneurons and preganglionic Edinger-Westphal motoneurons suggest that medial rectus C-group motoneurons may play a role in accommodation-related vergence. © 2017 Wiley Periodicals, Inc.

Disruption of medial septum and diagonal bands of Broca cholinergic projections to the ventral hippocampus disrupt auditory fear memory.

PubMed

Staib, Jennifer M; Della Valle, Rebecca; Knox, Dayan K

2018-07-01

In classical fear conditioning, a neutral conditioned stimulus (CS) is paired with an aversive unconditioned stimulus (US), which leads to a fear memory. If the CS is repeatedly presented without the US after fear conditioning, the formation of an extinction memory occurs, which inhibits fear memory expression. A previous study has demonstrated that selective cholinergic lesions in the medial septum and vertical limb of the diagonal bands of Broca (MS/vDBB) prior to fear and extinction learning disrupt contextual fear memory discrimination and acquisition of extinction memory. MS/vDBB cholinergic neurons project to a number of substrates that are critical for fear and extinction memory. However, it is currently unknown which of these efferent projections are critical for contextual fear memory discrimination and extinction memory. To address this, we induced cholinergic lesions in efferent targets of MS/vDBB cholinergic neurons. These included the dorsal hippocampus (dHipp), ventral hippocampus (vHipp), medial prefrontal cortex (mPFC), and in the mPFC and dHipp combined. None of these lesion groups exhibited deficits in contextual fear memory discrimination or extinction memory. However, vHipp cholinergic lesions disrupted auditory fear memory. Because MS/vDBB cholinergic neurons are the sole source of acetylcholine in the vHipp, these results suggest that MS/vDBB cholinergic input to the vHipp is critical for auditory fear memory. Taken together with previous findings, the results of this study suggest that MS/vDBB cholinergic neurons are critical for fear and extinction memory, though further research is needed to elucidate the role of MS/vDBB cholinergic neurons in these types of emotional memory. Copyright © 2018 Elsevier Inc. All rights reserved.

Bilateral lesions of the medial frontal cortex disrupt recognition of social hierarchy during antiphonal communication in naked mole-rats (Heterocephalus glaber).

PubMed

Yosida, Shigeto; Okanoya, Kazuo

2012-02-01

Generation of the motor patterns of emotional sounds in mammals occurs in the periaqueductal gray matter of the midbrain and is not directly controlled by the cortex. The medial frontal cortex indirectly controls vocalizations, based on the recognition of social context. We examined whether the medial frontal cortex was responsible for antiphonal vocalization, or turn-taking, in naked mole-rats. In normal turn-taking, naked mole-rats vocalize more frequently to dominant individuals than to subordinate ones. Bilateral lesions of the medial frontal cortex disrupted differentiation of call rates to the stimulus animals, which had varied social relationships to the subject. However, medial frontal cortex lesions did not affect either the acoustic properties of the vocalizations or the timing of the vocal exchanges. This suggests that the medial frontal cortex may be involved in social cognition or decision making during turn-taking, while other regions of the brain regulate when animals vocalize and the vocalizations themselves.

Comparison of Medial and Lateral Meniscus Root Tears.

PubMed

Koo, Ji Hyun; Choi, Sang-Hee; Lee, Seung Ah; Wang, Joon Ho

2015-01-01

The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients' ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29-71 years) and 30 years (range: 14-62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is common in

Comparison of Medial and Lateral Meniscus Root Tears

PubMed Central

Koo, Ji Hyun; Choi, Sang-Hee; Lee, Seung Ah; Wang, Joon Ho

2015-01-01

The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients’ ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29–71 years) and 30 years (range: 14–62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is

Predictive value of painful popping for a posterior root tear of the medial meniscus in middle-aged to older Asian patients.

PubMed

Bae, Ji-Hoon; Paik, Nak Hwan; Park, Gyu-Won; Yoon, Jung-Ro; Chae, Dong-Ju; Kwon, Jae Ho; Kim, Jong In; Nha, Kyung-Wook

2013-03-01

The purpose of this study was to determine the accuracy, sensitivity, specificity, and predictive values of a single event of painful popping in the presence of a posterior root tear of the medial meniscus in middle-aged to older Asian patients. We conducted a retrospective review of medical records of 936 patients who underwent arthroscopic surgeries for an isolated medial meniscus tear between January 2000 and December 2010. There were 332 men and 604 women with a mean age of 41 years (range, 25 to 66 years). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of a painful popping sensation for a posterior root tear of the medial meniscus were calculated. Arthroscopy confirmed the presence of posterior root tears of the medial menisci in 237 of 936 patients (25.3%). A single event of a painful popping sensation was present in 86 of these 936 patients (9.1%). Of these 86 patients with a painful popping sensation, 83 (96.5%) were categorized as having an isolated posterior root tear of the medial meniscus. The positive predictive value of a painful popping sensation in identifying a posterior root tear of the medial meniscus was 96.5%, the negative predictive value was 81.8%, the sensitivity was 35.0%, the specificity was 99.5%, and the diagnostic accuracy was 77.9%. A single event of painful popping can be a highly predictive clinical sign of a posterior root tear of the medial meniscus in the middle-aged to older Asian population. However, it has low sensitivity for the detection of a posterior root tear of the medial meniscus. Level IV, therapeutic case series. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Cognition and medial frontal cortex in health and disease

PubMed Central

Nachev, Parashkev

2009-01-01

Purpose of review Recent work on the role of medial frontal cortex in cognition and its involvement in neurological disorders is critically reviewed. Recent findings The highly influential notion of conflict monitoring by the anterior cingulate has been called into question by monkey single-cell neurophysiology and lesion studies in monkeys and humans. An alternative role for this region in adapting behaviour in response to changing demands over time is gaining support. By contrast, the more dorsally placed pre-supplementary motor area and supplementary eye field have been implicated in direct executive control in situations of response conflict. Although more rostral medial areas have been linked to complex cognitive operations involving references to the self, conceptual obstacles make the evidence difficult to interpret. The role of orbitofrontal cortex in guiding action based on value has been reinforced. Summary This area continues to generate both interest and controversy. A few striking discrepancies between data from functional imaging and interventional techniques illustrate the hazards of drawing strong conclusions from merely correlative evidence. More broadly, a case can be made for tempering the empirical enthusiasm here with a little more theoretical restraint. PMID:17102698

Exercise-induced stress resistance is independent of exercise controllability and the medial prefrontal cortex

PubMed Central

Greenwood, Benjamin N.; Spence, Katie G.; Crevling, Danielle M.; Clark, Peter J.; Craig, Wendy C.; Fleshner, Monika

2014-01-01

Exercise increases resistance against stress-related disorders such as anxiety and depression. Similarly, the perception of control is a powerful predictor of neurochemical and behavioral responses to stress, but whether the experience of choosing to exercise, and exerting control over that exercise, is a critical factor in producing exercise-induced stress resistance is unknown. The current studies investigated whether the protective effects of exercise against the anxiety- and depression-like consequences of stress are dependent on exercise controllability and a brain region implicated in the protective effects of controllable experiences, the medial prefrontal cortex. Adult male Fischer 344 rats remained sedentary, were forced to run on treadmills or motorised running wheels, or had voluntary access to wheels for 6 weeks. Three weeks after exercise onset, rats received sham surgery or excitotoxic lesions of the medial prefrontal cortex. Rats were exposed to home cage or uncontrollable tail shock treatment three weeks later. Shock-elicited fear conditioning and shuttle box escape testing occurred the next day. Both forced and voluntary wheel running, but not treadmill training, prevented the exaggerated fear conditioning and interference with escape learning produced by uncontrollable stress. Lesions of the medial prefrontal cortex failed to eliminate the protective effects of forced or voluntary wheel running. These data suggest that exercise controllability and the medial prefrontal cortex are not critical factors in conferring the protective effects of exercise against the affective consequences of stressor exposure, and imply that exercise perceived as forced may still benefit affect and mental health. PMID:23121339

Three-dimensional knee motion before and after high tibial osteotomy for medial knee osteoarthritis.

PubMed

Takemae, Takashi; Omori, Go; Nishino, Katsutoshi; Terajima, Kazuhiro; Koga, Yoshio; Endo, Naoto

2006-11-01

High tibial osteotomy (HTO) is an established surgical option for treating medial knee osteoarthritis. HTO moves the mechanical load on the knee joint from the medial compartment to the lateral compartment by changing the leg alignment, but the effects of the operation remain unclear. The purpose of this study was to evaluate the change in three-dimensional knee motion before and after HTO, focusing on lateral thrust and screw home movement, and to investigate the relationship between the change in knee motion and the clinical results. A series of 19 patients with medial knee osteoarthritis who had undergone HTO were evaluated. We performed a clinical assessment, radiological evaluation, and motion analysis at 2.4 years postoperatively. The clinical assessment was performed using the Japanese Orthopaedic Association knee score. The score was significantly improved in all patients after operation. Motion analysis revealed that lateral thrust, which was observed in 18 of the 20 knees before operation, was reduced to 7 knees after operation. Regarding active terminal extension of the knee, three patterns of rotational movement were observed before operation: screw home movement (external rotation), reverse screw home movement (internal rotation), and no rotation. By contrast, after operation, only reverse screw home movement and no rotation were observed; the screw home movement disappeared in all patients. In the knees with reverse screw home movement after operation, the preoperative score was significantly lower than those in the knees with no rotation after operation. Kinetically, HTO was useful for suppressing lateral thrust in medial knee osteoarthritis, although the rotational movement of the knee joint was unchanged.

Functional engraftment of the medial ganglionic eminence cells in experimental stroke model.

PubMed

Daadi, Marcel M; Lee, Sang Hyung; Arac, Ahmet; Grueter, Brad A; Bhatnagar, Rishi; Maag, Anne-Lise; Schaar, Bruce; Malenka, Robert C; Palmer, Theo D; Steinberg, Gary K

2009-01-01

Currently there are no effective treatments targeting residual anatomical and behavioral deficits resulting from stroke. Evidence suggests that cell transplantation therapy may enhance functional recovery after stroke through multiple mechanisms. We used a syngeneic model of neural transplantation to explore graft-host communications that enhance cellular engraftment.The medial ganglionic eminence (MGE) cells were derived from 15-day-old transgenic rat embryos carrying green fluorescent protein (GFP), a marker, to easily track the transplanted cells. Adult rats were subjected to transient intraluminal occlusion of the medial cerebral artery. Two weeks after stroke, the grafts were deposited into four sites, along the rostro-caudal axis and medially to the stroke in the penumbra zone. Control groups included vehicle and fibroblast transplants. Animals were subjected to motor behavioral tests at 4 week posttransplant survival time. Morphological analysis demonstrated that the grafted MGE cells differentiated into multiple neuronal subtypes, established synaptic contact with host cells, increased the expression of synaptic markers, and enhanced axonal reorganization in the injured area. Initial patch-clamp recording demonstrated that the MGE cells received postsynaptic currents from host cells. Behavioral analysis showed reduced motor deficits in the rotarod and elevated body swing tests. These findings suggest that graft-host interactions influence the fate of grafted neural precursors and that functional recovery could be mediated by neurotrophic support, new synaptic circuit elaboration, and enhancement of the stroke-induced neuroplasticity.

Molecular recognition of DNA base pairs by the formamido/pyrrole and formamido/imidazole pairings in stacked polyamides

PubMed Central

Buchmueller, Karen L.; Staples, Andrew M.; Uthe, Peter B.; Howard, Cameron M.; Pacheco, Kimberly A. O.; Cox, Kari K.; Henry, James A.; Bailey, Suzanna L.; Horick, Sarah M.; Nguyen, Binh; Wilson, W. David; Lee, Moses

2005-01-01

Polyamides containing an N-terminal formamido (f) group bind to the minor groove of DNA as staggered, antiparallel dimers in a sequence-specific manner. The formamido group increases the affinity and binding site size, and it promotes the molecules to stack in a staggered fashion thereby pairing itself with either a pyrrole (Py) or an imidazole (Im). There has not been a systematic study on the DNA recognition properties of the f/Py and f/Im terminal pairings. These pairings were analyzed here in the context of f-ImPyPy, f-ImPyIm, f-PyPyPy and f-PyPyIm, which contain the central pairing modes, –ImPy– and –PyPy–. The specificity of these triamides towards symmetrical recognition sites allowed for the f/Py and f/Im terminal pairings to be directly compared by SPR, CD and ΔTM experiments. The f/Py pairing, when placed next to the –ImPy– or –PyPy– central pairings, prefers A/T and T/A base pairs to G/C base pairs, suggesting that f/Py has similar DNA recognition specificity to Py/Py. With –ImPy– central pairings, f/Im prefers C/G base pairs (>10 times) to the other Watson–Crick base pairs; therefore, f/Im behaves like the Py/Im pair. However, the f/Im pairing is not selective for the C/G base pair when placed next to the –PyPy– central pairings. PMID:15703305

Molecular recognition of DNA base pairs by the formamido/pyrrole and formamido/imidazole pairings in stacked polyamides.

PubMed

Buchmueller, Karen L; Staples, Andrew M; Uthe, Peter B; Howard, Cameron M; Pacheco, Kimberly A O; Cox, Kari K; Henry, James A; Bailey, Suzanna L; Horick, Sarah M; Nguyen, Binh; Wilson, W David; Lee, Moses

2005-01-01

Polyamides containing an N-terminal formamido (f) group bind to the minor groove of DNA as staggered, antiparallel dimers in a sequence-specific manner. The formamido group increases the affinity and binding site size, and it promotes the molecules to stack in a staggered fashion thereby pairing itself with either a pyrrole (Py) or an imidazole (Im). There has not been a systematic study on the DNA recognition properties of the f/Py and f/Im terminal pairings. These pairings were analyzed here in the context of f-ImPyPy, f-ImPyIm, f-PyPyPy and f-PyPyIm, which contain the central pairing modes, -ImPy- and -PyPy-. The specificity of these triamides towards symmetrical recognition sites allowed for the f/Py and f/Im terminal pairings to be directly compared by SPR, CD and DeltaT (M) experiments. The f/Py pairing, when placed next to the -ImPy- or -PyPy- central pairings, prefers A/T and T/A base pairs to G/C base pairs, suggesting that f/Py has similar DNA recognition specificity to Py/Py. With -ImPy- central pairings, f/Im prefers C/G base pairs (>10 times) to the other Watson-Crick base pairs; therefore, f/Im behaves like the Py/Im pair. However, the f/Im pairing is not selective for the C/G base pair when placed next to the -PyPy- central pairings.

Fundamental aspects of recoupled pair bonds. I. Recoupled pair bonds in carbon and sulfur monofluoride

NASA Astrophysics Data System (ADS)

Dunning, Thom H.; Xu, Lu T.; Takeshita, Tyler Y.

2015-01-01

The number of singly occupied orbitals in the ground-state atomic configuration of an element defines its nominal valence. For carbon and sulfur, with two singly occupied orbitals in their 3P ground states, the nominal valence is two. However, in both cases, it is possible to form more bonds than indicated by the nominal valence—up to four bonds for carbon and six bonds for sulfur. In carbon, the electrons in the 2s lone pair can participate in bonding, and in sulfur the electrons in both the 3p and 3s lone pairs can participate. Carbon 2s and sulfur 3p recoupled pair bonds are the basis for the tetravalence of carbon and sulfur, and 3s recoupled pair bonds enable sulfur to be hexavalent. In this paper, we report generalized valence bond as well as more accurate calculations on the a4Σ- states of CF and SF, which are archetypal examples of molecules that possess recoupled pair bonds. These calculations provide insights into the fundamental nature of recoupled pair bonds and illustrate the key differences between recoupled pair bonds formed with the 2s lone pair of carbon, as a representative of the early p-block elements, and recoupled pair bonds formed with the 3p lone pair of sulfur, as a representative of the late p-block elements.

Working Memory, Long-Term Memory, and Medial Temporal Lobe Function

ERIC Educational Resources Information Center

Jeneson, Annette; Squire, Larry R.

2012-01-01

Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance…

Articular cartilage scores in cranial cruciate ligament-deficient dogs with or without bucket handle tears of the medial meniscus.

PubMed

Kaufman, Kathryn; Beale, Brian S; Thames, Howard D; Saunders, W Brian

2017-01-01

To compare articular cartilage scores in cranial cruciate ligament (CCL)-deficient dogs with or without concurrent bucket handle tears (BHT) of the medial meniscus. Retrospective case series. Client-owned dogs treated with arthroscopy and tibial plateau leveling osteotomy or extracapsular repair for complete CCL rupture (290 stifles from 264 dogs). Medical records and arthroscopic images were reviewed. Medial femoral condyle (MFC) and medial tibial plateau (MTP) cartilage was scored using the modified Outerbridge scale. Periarticular osteophytosis (PAO) and injury to the medial meniscus were recorded. Data were analyzed using Student's t-tests, Wilcoxon rank-sum test, and Fisher's exact test for changes in the stifle based on meniscal condition, body weight, and duration of lameness. PAO, MFC, and MTP articular cartilage scores were not significantly different in dogs with or without BHT. There were no significant differences in MFC or MTP scores when dogs were evaluated based on bodyweight and the presence or absence of a BHT. However, PAO formation was significantly increased in dogs weighing >13.6 kg and concurrent meniscal injury vs. dogs weighing <13.6 kg and concurrent meniscal injury (P < .001). Significantly more stifles with chronic lameness (40 of 89; 44.9%) had the highest PAO score of 2 reported compared to only 42 of 182 stifles (23.1%) with acute lameness (P < .001). The presence of a BHT of the medial meniscus was not associated with more severe arthroscopic articular cartilage lesions in the medial joint compartment at the time of surgery. © 2016 The American College of Veterinary Surgeons.

Study of Fos, androgen receptor and testosterone expression in the sub-regions of medial amygdala, bed nucleus of stria terminalis and medial preoptic area in male Mandarin voles in response to chemosensory stimulation.

PubMed

He, Fengqin; Wu, Ruiyong; Yu, Peng

2014-01-01

In many rodent species, including mandarin voles (Microtus mandarinus), the behavioral response to odors is regulated by a network of steroid-sensitive ventral forebrain nuclei including the medial amygdala (Me), bed nucleus of the striaterminalis (BNST), and medial preoptic area (MPOA). Although it is well-known that Me, BNST, and MPOA are closely interconnected, function independently in regulating odor-guided social behaviors, little is known about how order information is processed in the sub-regions of Me, BNST, and MPOA. In order to answer this question, we let male mandarin voles expose to two different odors including female vaginal fluid (FVF) and male flank gland secretion (MFGS) and detect the expression of Fos, androgen receptor (AR) and testosterone (T) in the sub-regions of Me, BNST, and MPOA. We found that FVF stimulus caused increased Fos, AR and T expression in the posterior subdivision of the Me (MeP), the posterior medial subdivision of the BNST (BNSTpm), and the medial preoptic nucleus (MPN), while MFGS stimulus did not change Fos, AR and T expression neither in the MeP, BNSTpm, and MPN nor in the anterior subdivision of the Me (MeA), the posterointermediate subdivision of the BNST (BNSTpi), and the lateral subdivision of the MPOA (MPOAl). Serum testosterone levels were increased after 1h in males exposed to FVF. This study provides insight in understanding the relationship between female odor stimulation and Fos, AR and T expression in specific brain areas in males, and the regulatory role of testosterone in this biochemical process. Copyright © 2013 Elsevier B.V. All rights reserved.

Treatment of subtotal medial rectus myectomy complicating functional endoscopic sinus surgery.

PubMed

Trotter, W L; Kaw, P; Meyer, D R; Simon, J W

2000-08-01

During the past 2 decades, the introduction of functional endoscopic sinus surgery (FESS) has dramatically improved the treatment of sinus disorders. However, a variety of orbital complications have been reported, including optic nerve damage, hemorrhage, infection, compromise of the lacrimal drainage apparatus, and strabismus. At least 10 cases have reported damage to the medial rectus muscle. (1-8) Treatment options for such patients have been limited, especially because most are adults at risk for anterior segment ischemia after transposition of vertical rectus muscles. We describe 2 patients whose medial rectus myectomies were repaired by using nonabsorbable "hang-back" sutures in combination with a botulinum toxin (Botox) injection of the antagonist lateral rectus muscle. Good primary position alignment was achieved in both patients, and one patient was able to regain binocular function. We recommend this surgical approach, especially in patients at increased risk for anterior segment ischemia.

Does location of patellofemoral chondral lesion influence outcome after Oxford medial compartmental knee arthroplasty?

PubMed

Konan, S; Haddad, F S

2016-10-01

Medial unicompartmental knee arthroplasty (UKA) is associated with successful outcomes in carefully selected patient cohorts. We hypothesised that severity and location of patellofemoral cartilage lesions significantly influences functional outcome after Oxford medial compartmental knee arthroplasty. We reviewed 100 consecutive UKAs at minimum eight-year follow-up (96 to 132). A single surgeon performed all procedures. Patients were selected based on clinical and plain radiographic assessment. All patients had end-stage medial compartment osteoarthritis (OA) with sparing of the lateral compartment and intact anterior cruciate ligaments. None of the patients had end-stage patellofemoral OA, but patients with anterior knee pain or partial thickness chondral loss were not excluded. There were 57 male and 43 female patients. The mean age at surgery was 69 years (41 to 82). At surgery the joint was carefully inspected for patellofemoral chondral loss and this was documented based on severity of cartilage loss (0 to 4 Outerbridge grading) and topographic location (medial, lateral, central, and superior or inferior). Functional scores collected included Oxford Knee Score (OKS), patient satisfaction scale and University College Hospital (UCH) knee score. Intraclass correlation was used to compare chondral damage to outcomes. All patients documented significant improvement in pain and improved functional scores at mid-term follow-up. There were four revisions (mean 2.9 years, 2 to 4; standard deviation (sd) 0.9) in this cohort, three for tibial loosening and one for femoral loosening. There was one infection that was treated with debridement and insert exchange. The mean OKS improved from 23.2 (sd 7.1) to 39.1 (sd 6.9); p < 0.001. The cohort with central and lateral grade 3 patellofemoral OA documented lower mean satisfaction with pain (90, sd 11.8) and function (87.5, sd 10.3) on the patient satisfaction scale. On the UCH scale, patients reported significantly decreased

Does location of patellofemoral chondral lesion influence outcome after Oxford medial compartmental knee arthroplasty?

PubMed Central

Konan, S.; Haddad, F. S.

2016-01-01

Aims Medial unicompartmental knee arthroplasty (UKA) is associated with successful outcomes in carefully selected patient cohorts. We hypothesised that severity and location of patellofemoral cartilage lesions significantly influences functional outcome after Oxford medial compartmental knee arthroplasty. Patients and Methods We reviewed 100 consecutive UKAs at minimum eight-year follow-up (96 to 132). A single surgeon performed all procedures. Patients were selected based on clinical and plain radiographic assessment. All patients had end-stage medial compartment osteoarthritis (OA) with sparing of the lateral compartment and intact anterior cruciate ligaments. None of the patients had end-stage patellofemoral OA, but patients with anterior knee pain or partial thickness chondral loss were not excluded. There were 57 male and 43 female patients. The mean age at surgery was 69 years (41 to 82). At surgery the joint was carefully inspected for patellofemoral chondral loss and this was documented based on severity of cartilage loss (0 to 4 Outerbridge grading) and topographic location (medial, lateral, central, and superior or inferior). Functional scores collected included Oxford Knee Score (OKS), patient satisfaction scale and University College Hospital (UCH) knee score. Intraclass correlation was used to compare chondral damage to outcomes. Results All patients documented significant improvement in pain and improved functional scores at mid-term follow-up. There were four revisions (mean 2.9 years, 2 to 4; standard deviation (sd) 0.9) in this cohort, three for tibial loosening and one for femoral loosening. There was one infection that was treated with debridement and insert exchange. The mean OKS improved from 23.2 (sd 7.1) to 39.1 (sd 6.9); p < 0.001. The cohort with central and lateral grade 3 patellofemoral OA documented lower mean satisfaction with pain (90, sd 11.8) and function (87.5, sd 10.3) on the patient satisfaction scale. On the UCH scale, patients

Graft extrusion in both the coronal and sagittal planes is greater after medial compared with lateral meniscus allograft transplantation but is unrelated to early clinical outcomes.

PubMed