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Sample records for partial medial meniscectomy

  1. Gender Effect on the Outcome of Partial Medial Meniscectomy.

    PubMed

    Haviv, Barak; Bronak, Shlomo; Kosashvili, Yona; Thein, Rafael

    2015-10-01

    Complex posterior horn tears of the medial meniscus are common. Previous reports performed statistical stratifications to address the influence of gender on outcome following arthroscopic partial medial meniscectomy with variable conclusions. The aim of this study was to compare the clinical results of arthroscopic partial meniscectomy of the knee between men and women with complex medial meniscal tear type while controlling for other variables that may affect outcome. This study compared groups of 86 men and 49 women who were followed prospectively using the Lysholm Knee Scoring Scale, the visual analogue scale, and patient's satisfaction. Mean age at operation was 51 years and mean follow-up was 26 months. Mean Lysholm score improved from 69 preoperatively to 82.1 postoperatively (P<.001) in the male group and from 64.2 preoperatively to 73.5 postoperatively (P=.04) in the female group. At last follow-up, 68 (79%) men and 35 (71%) women stated that they were satisfied with the operation. In both groups, the severity of chondral lesions was found to be negatively correlated to the preoperative score. Women had more severe chondral lesions at arthroscopy than men. This comparative study showed no significant difference between men and women in terms of clinical improvement following arthroscopic partial meniscectomies of complex tear types in stable knees with intact lateral meniscus. Women had lower functionality pre- and postoperatively, which correlated with more severe chondral degeneration at surgery compared with men. PMID:26488789

  2. Why arthroscopic partial meniscectomy?

    PubMed

    Lyu, Shaw-Ruey

    2015-09-01

    "Arthroscopic Partial Meniscectomy versus Sham Surgery for a Degenerative Meniscal Tear" published in the New England Journal of Medicine on December 26, 2013 draws the conclusion that arthroscopic partial medial meniscectomy provides no significant benefit over sham surgery in patients with a degenerative meniscal tear and no knee osteoarthritis. This result argues against the current practice of performing arthroscopic partial meniscectomy (APM) in patients with a degenerative meniscal tear. Since the number of APM performed has been increasing, the information provided by this study should lead to a change in clinical care of patients with a degenerative meniscus tear. PMID:26488013

  3. Evaluation of Joint Space Width and Narrowing After Isolated Partial Medial Meniscectomy for Degenerative Medial Meniscus Tears

    PubMed Central

    Shelbourne, K. Donald; Barnes, Adam F.; Urch, Scott E.; Gray, Tinker

    2013-01-01

    significantly lower than the mean of 82.7 points for men (P < .01). Conclusion: Patients undergoing partial medial meniscectomy have greater joint space narrowing and lower subjective scores after surgery if they also have existing Outerbridge grade 3-4 damage. Women have less normal joint space than men, and more women than men experience >50% joint space narrowing after surgery. PMID:26535250

  4. 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

  5. Efficacy test of Polycan, a beta-glucan originated from Aureobasidium pullulans SM-2001, on anterior cruciate ligament transection and partial medial meniscectomy-induced-osteoarthritis rats.

    PubMed

    Kim, Joo-Wan; Cho, Hyung-Rae; Ku, Sae-Kwang

    2012-02-01

    The object of this study was to assess the efficacy of Polycan from Aureobasidium pullulans SM-2001, which is composed mostly of beta-1,3-1,6-glucan, on osteoarthritis (OA)-induced by anterior cruciate ligament transection and partial medial meniscectomy (ACLT&PMM). Three different dosages of Polycan (85, 42.5, and 21.25 mg/kg) were orally administered once a day for 84 days to male rats a week after ACLT&PMM surgery. Changes in the circumference and maximum extension angle of each knee, and in cartilage histopathology were assessed using Mankin scores 12 weeks after Polycan administration. In addition, cartilage proliferation was evaluated using bromodeoxyuridine (BrdU). As the result of ACLT&PMM, classic OA was induced with increases in maximum extension angles, edematous knees changes, and capsule thickness, as well as decreases in chondrocyte proliferation, cartilages degenerative changes, and loss of articular cartilage. However, these changes (except for capsule thickness) were markedly inhibited in all Polycan- and diclofenac sodium-treated groups compared with OA control. Although diclofenac sodium did not influence BrdU uptake, BrdU-immunoreactive cells were increased with all dosages of Polycan, which means that Polycan treatment induced proliferation of chondrocytes in the surface articular cartilage of the tibia and femur. The results obtained in this study suggest that 84 days of continuous oral treatment of three different dosages of Polycan led to lesser degrees of articular stiffness and histological cartilage damage compared with OA controls 91 days after OA inducement, suggesting that the optimal Polycan dosage to treat OA is 42.5 mg/kg based on the present study. PMID:22370362

  6. RNA Microarray Analysis of Macroscopically Normal Articular Cartilage from Knees Undergoing Partial Medial Meniscectomy: Potential Prediction of the Risk for Developing Osteoarthritis

    PubMed Central

    Sandell, Linda J.; Zhang, Bo; Wright, Rick W.; Brophy, Robert H.

    2016-01-01

    Objectives (i) To provide baseline knowledge of gene expression in macroscopically normal articular cartilage, (ii) to test the hypothesis that age, body-mass-index (BMI), and sex are associated with cartilage RNA transcriptome, and (iii) to predict individuals at potential risk for developing “pre-osteoarthritis” (OA) based on screening of genetic risk-alleles associated with OA and gene transcripts differentially expressed between normal and OA cartilage. Design Healthy-appearing cartilage was obtained from the medial femoral notch of 12 knees with a meniscus tear undergoing arthroscopic partial meniscectomy. Cartilage had no radiographic, magnetic-resonance-imaging or arthroscopic evidence for degeneration. RNA was subjected to Affymetrix microarrays followed by validation of selected transcripts by microfluidic digital polymerase-chain-reaction. The underlying biological processes were explored computationally. Transcriptome-wide gene expression was probed for association with known OA genetic risk-alleles assembled from published literature and for comparison with gene transcripts differentially expressed between healthy and OA cartilage from other studies. Results We generated a list of 27,641 gene transcripts in healthy cartilage. Several gene transcripts representing numerous biological processes were correlated with age and BMI and differentially expressed by sex. Based on disease-specific Ingenuity Pathways Analysis, gene transcripts associated with aging were enriched for bone/cartilage disease while the gene expression profile associated with BMI was enriched for growth-plate calcification and OA. When segregated by genetic risk-alleles, two clusters of study patients emerged, one cluster containing transcripts predicted by risk studies. When segregated by OA-associated gene transcripts, three clusters of study patients emerged, one of which is remarkably similar to gene expression pattern in OA. Conclusions Our study provides a list of gene

  7. Arthroscopic partial meniscectomy for horizontal tear of discoid lateral meniscus.

    PubMed

    Bin, Seong-Il; Jeong, Sang-Il; Kim, Jong-Min; Shon, Hyun-Chul

    2002-01-01

    A new method of arthroscopic partial meniscectomy for horizontal tear of discoid lateral meniscus was devised to preserve as much meniscal tissue as possible. To evaluate the clinical result of this method for horizontal tear of discoid lateral meniscus, 31 knees (30 patients) were reviewed at an average follow-up of 35 months (range 14-48 months). Horizontally torn discoid lateral menisci were classified as incomplete (11 cases) or complete (20 cases) by the Watanabe classification; no Wrisberg type was noted. Partial meniscectomy was performed in all cases. For the technique of a new method of partial meniscectomy, the unstable leaf of the horizontally torn meniscus was removed to the peripheral rim, but the stable one was preserved and reshaped to produce the similar appearance to the normal lateral meniscus in terms of width and thickness. It was trimmed to have a balanced rim of meniscal tissue about 6-8 mm in width. Meniscal repair was added to partial meniscectomy in one case. All the cases were rated using the Lysholm Knee Scoring Scale and were reviewed to recognize retear clinically. The scores increased after partial meniscectomy by average 20.7 (from 73.0 to 93.7). Recurrence of tear or aggravation of symptoms was not noted at the final follow-up. PMID:11819016

  8. In vitro load transmission in the canine knee: the effect of medial meniscectomy and varus rotation.

    PubMed

    Anderson, D R; Newman, A P; Daniels, A U

    1993-01-01

    The purpose of this study was to determine the in vitro load-transmission characteristics of the canine knee, paying particular attention to the positioning effect of the meniscus in the coronal plane. The intact joint was first loaded and then tested under two different loading conditions after a complete medial meniscectomy. The first set of test conditions attempted to simulate those used by previous investigators, by ignoring the spacer effect of the meniscus. The second set of tests were carried out following varus rotation of the joint (to account for the loss of the meniscal spacer) to assure initial contact in both tibiofemoral compartments at the start of test cycle. It is presumed that this varus realignment occurs during weight bearing following meniscectomy in vivo. As in previous studies, the joints experienced slightly larger displacements (although not statistically significant) and had lower stiffness values following medial meniscectomy than when intact. However, following varus realignment of the joint after meniscectomy, the displacement was markedly smaller (-35% to -49%; P < 0.01) and the structural stiffness was much greater (47-123%; P < 0.05) over the range of forces analyzed, compared with the intact joint. The ratio of dissipated to input energy was 42% for the intact joint, and increased following meniscectomy to 54% (P < 0.05) with realignment and 55% (P < 0.05) without realignment. Measured contact area decreased by 17% (P < 0.05) following meniscectomy alone, and by 12% (P < 0.05) following meniscectomy with realignment.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8535997

  9. Radial displacement of lateral meniscus after partial meniscectomy.

    PubMed

    Choi, Nam-Hong

    2006-05-01

    Radial displacement or extrusion of the meniscus has been reported as a complication after meniscal transplantation and is sometimes observed in knees with advanced osteoarthritis. In this report, the case of a patient with radial displacement of the lateral meniscus after partial meniscectomy is presented. He had an incomplete discoid lateral meniscus with an anterior horn tear. The inner portion of the lateral meniscus was excised to leave a width of 8 to 10 mm. However, follow-up magnetic resonance imaging showed radial displacement of the mid-body of the lateral meniscus and a compatible finding of chondromalacia of the lateral compartment of the knee. PMID:16651179

  10. Arthroscopic Meniscectomy for Medial Meniscus Horizontal Cleavage Tears in Patients under Age 45

    PubMed Central

    Kim, Jae Gyoon; Lee, Seung-Yup; Chay, Suhwoo; Lim, Hong Chul

    2016-01-01

    Purpose The purpose of this study was to evaluate the demographics, clinical features, and outcomes of arthroscopic partial meniscectomy (APM) for isolated medial meniscus horizontal cleavage tears (MMHCTs) in patients under 45 years of age. Materials and Methods We retrospectively reviewed 98 patients (100 knees) under 45 years who underwent APM for MMHCTs. Clinical outcomes were assessed using International Knee Document Committee (IKDC) subjective core, Tegner activity scale, visual analog scale (VAS) pain score, and a question on the symptom relief. Results 79% were male and 70% had no trauma. The mean symptom duration was 10 months. At arthroscopy, a flap tear was identified in 75%. At a mean of 19-month follow-up, the IKDC subjective score, Tegner activity scale, and VAS pain score were significantly improved compared to the preoperative values (p=0.025, p=0.043, and p=0.032, respectively). While 85% were free of symptoms, 15% had persistent pain. No significant differences in outcomes were observed based on the tear type and the presence of flap tears. No progression or development of radiographic degenerative changes was observed in all knees. Conclusions Demographics of MMHCTs under age 45 showed a male dominance and higher frequency of non-traumatic tears. APM was beneficial to symptomatic HCTs in this cohort during the short-term follow-up. Type of HCTs and combined flap tears did not affect clinical outcomes. PMID:27595077

  11. The effect of medial meniscectomy and coronal plane angulation on in vitro load transmission in the canine stifle joint.

    PubMed

    Newman, A P; Anderson, D R; Daniels, A U; Jee, K W

    1989-01-01

    The purpose of this study was to determine the in vitro load transmission characteristics of the canine stifle joint, paying particular attention to the positioning effect of the meniscus in the coronal plane. The intact joint was first loaded, and then tested under two different loading conditions after a complete medial meniscectomy. The first set of test conditions attempted to simulate those used by previous investigators, by ignoring the spacer effect of the meniscus and not repositioning the joint after its removal. The second set of tests was carried out after the joint was repositioned in the coronal plane to allow initial contact to occur in both tibiofemoral compartments. It is presumed that this occurs subsequent to a meniscectomy in vivo, following the application of any weight-bearing load. As with previous investigators, it was found that after meniscectomy the joints produced slightly larger displacements and lower stiffnesses than when intact (no significant differences from intact). However, repositioning the meniscectomized joint produced markedly smaller displacements (35-49%, p less than 0.01) and greater stiffnesses (47-123%, p less than 0.05) over the range of forces analyzed, compared with the intact joint. The ratio of dissipated to input energy was 42% for the intact joint, and rose following meniscectomy to 54% (p less than 0.05) with repositioning and 55% (p less than 0.05) without repositioning. Measured contact area decreased by 17% (p less than 0.05) following meniscectomy alone, and by 12% (p less than 0.05) following meniscectomy with repositioning. Since repositioning of the joint subsequent to meniscectomy (accounting for the loss of the meniscal spacer) resulted in an increase in structural stiffness, it was concluded that the medial meniscus decreases the structural stiffness of the intact stifle joint. In addition, the meniscus has a role in elastic energy storage and increasing contact area. This study is intended to serve as a

  12. Chondropathy after meniscal tear or partial meniscectomy in a canine model.

    PubMed

    Wyland, Douglas J; Guilak, Farshid; Elliott, Dawn M; Setton, Lori A; Vail, Thomas P

    2002-09-01

    A primary goal in considering treatment for meniscal injuries is the preservation of the health of the articular cartilage. However, the chondroprotective effects of various techniques for meniscal injury treatments are unknown. We used a canine model to quantify articular cartilage degeneration in the medial compartment of the canine knee, resulting from a surgically created tear or a partial meniscectomy (PM) of the posterior region of the medial meniscus (each group, n = 10). After sacrifice at 12 weeks, the development of gross chondropathy and the changes in cartilage tensile stiffness were quantified, and correlations between these measurements were examined. Both treatment surgical treatment groups caused significantly greater gross chondropathy as compared to the unoperated contralateral controls. Cartilage tensile stiffness was significantly lower than unoperated controls by nearly 28% in both experimental groups. However, there were no significant differences observed between the gross chondropathy or the cartilage mechanical property changes between the experimental groups. Importantly, the severity of gross chondropathy was found to significantly correlate with the decrement in tensile stiffness properties of the articular cartilage. These findings indicate that significant degeneration of canine articular cartilage develops to a similar degree in the presence of a partially healed meniscus tear or a PM of the knee. PMID:12382965

  13. The Effect of ACL Reconstruction on Kinematics of the Knee with Combined ACL Injury and Subtotal Medial Meniscectomy - an in-vitro robotic investigation

    PubMed Central

    Seon, Jong Keun; Gadikota, Hemanth R.; Kozanek, Michal; Oh, Luke S.; Gill, Thomas J.; Li, Guoan

    2009-01-01

    Purpose The aims of this study were to determine: 1) the kinematic effect of subtotal medial meniscectomy on ACL deficient knee and 2) the effect of ACL reconstruction on kinematics of the knee with combined ACL deficiency and subtotal medial meniscectomy under an anterior tibial and a simulated quadriceps loads. Methods Eight human cadaveric knees were sequentially tested using a robotic testing system under 4 conditions: intact, ACL deficiency, ACL deficiency with subtotal medial meniscectomy, and single bundle ACL reconstruction using a bone-patellar tendon-bone graft. Knee kinematics were measured at 0°, 15°, 30°, 60°, and 90° of flex ion under an anterior tibial load of 130 N and a quadriceps muscle load of 400 N. Results Subtotal medial meniscectomy in ACL deficient knee significantly increased anterior and lateral tibial translations under the anterior tibial and quadriceps loads (P < 0.05). These kinematic changes were larger at high flexion (≥ 60°) than at low flexion angles. ACL reconstructio n in knees with ACL deficiency and subtotal medial meniscectomy significantly reduced the increased anterior tibial translation, but could not restore anterior translation to the intact level with differences ranging from 2.6 mm at 0° to 5.5 mm at 30° of flexion. ACL reconstruction did not significantly affect the medial-lateral translation and internal-external tibial rotation in the presence of subtotal meniscectomy. Conclusions Subtotal medial meniscectomy in knees with ACL deficiency altered knee kinematics, especially at high flexion angles. ACL reconstruction significantly reduced the increased tibial translation in knees with combined ACL deficiency and subtotal medial meniscectomy, but could not restore the knee kinematics to the intact knee level. Clinical Relevance This study suggests that meniscus is an important secondary stabilizer against anterior and lateral tibial translations and should be preserved in the setting of ACL reconstruction for

  14. A longitudinal study of impact and early stance loads during gait following arthroscopic partial meniscectomy.

    PubMed

    Hall, Michelle; Wrigley, Tim V; Metcalf, Ben R; Hinman, Rana S; Dempsey, Alasdair R; Mills, Peter M; Cicuttini, Flavia M; Lloyd, David G; Bennell, Kim L

    2014-09-22

    People following arthroscopic partial medial meniscectomy (APM) are at increased risk of developing knee osteoarthritis. High impact loading and peak loading early in the stance phase of gait may play a role in the pathogenesis of knee osteoarthritis. This was a secondary analysis of longitudinal data to investigate loading-related indices at baseline in an APM group (3 months post-surgery) and a healthy control group, and again 2 years later (follow-up). At baseline, 82 participants with medial APM and 38 healthy controls were assessed, with 66 and 23 re-assessed at follow-up, respectively. Outcome measures included: (i) heel strike transient (HST) presence and magnitude, (ii) maximum loading rate, (iii) peak vertical force (Fz) during early stance. At baseline, maximum loading rate was lower in the operated leg (APM) and non-operated leg (non-APM leg) compared to controls (p ≤ 0.03) and peak Fz was lower in the APM leg compared to non-APM leg (p ≤ 0.01). Over 2 years, peak Fz increased in the APM leg compared to the non-APM leg and controls (p ≤ 0.01). Following recent APM, people may adapt their gait to protect the operated knee from excessive loads, as evidenced by a lower maximum loading rate in the APM leg compared to controls, and a reduced peak Fz in the APM leg compared to the non-APM leg. No differences at follow-up may suggest an eventual return to more typical gait. However, the increase in peak Fz in the APM leg may be of concern for long-term joint health given the compromised function of the meniscus. PMID:25169661

  15. Results of Arthroscopic Partial Meniscectomy for Lateral Discoid Meniscus Tears Associated with New Technique

    PubMed Central

    Lee, Chul-Hyung; Jang, Sung-Won; Cha, Hong-Eun

    2013-01-01

    Purpose To introduce and evaluate the clinical results of a new arthroscopic technique for partial meniscectomy of symptomatic lateral discoid meniscus using a knife. Materials and Methods From March 2005 to October 2010, 60 knees of 58 patients underwent arthroscopic partial meniscectomies for lateral discoid meniscus. The average age was 28.9 years (range, 12 to 63 years), and average follow-up was 26 months (range, 8 to 72 years). In this procedure, using a No. 11 knife holder inserted through the high far anteromedial portal, a stab incision on the anterior meniscal horn and following piecemeal meniscal excision were made. Clinical results were assessed using the scale of Ikeuchi and Lysholm score. Results Meniscus shape was complete in 32 knees (53.3%) and incomplete in 28 knees (46.6%). The shape of tears in complete type lesions was horizontal cleavage in 17 knees (53.1%), flap or complex degenerated tears in 10 knees (31.2%) and radial tears in 5 knees (15.6%). Clinical results assessed using the scale of Ikeuchi were excellent in 38 (63.3%), good in 13 (21.6%), fair in 8 (13.3%) and poor in 1 knee (1.6%). The average Lysholm score was improved from 82.8 preoperatively to 95.4 postoperatively. Conclusions Our new arthroscopic technique in lateral discoid partial meniscectomy suggests convenient methods and successful clinical results. PMID:23508292

  16. Combined Effect of Bilateral Ovariectomy and Anterior Cruciate Ligament Transection With Medial Meniscectomy on the Development of Osteoarthritis Model

    PubMed Central

    2016-01-01

    Objective To investigate the combined effect of bilateral ovariectomy (OVX) and anterior cruciate ligament transection (ACLT) with medial meniscectomy (MM) on the development of osteoarthritis (OA). Methods Twenty female 15-week-old Sprague-Dawley rats were used. Five rats in each group underwent bilateral OVX (OVX group), bilateral ACLT with MM (ACLT with MM group), bilateral OVX plus ACLT with MM (OVX plus ACLT with MM group), and sham surgery (SHAM group). All the rats were subjected to treadmill running for 4 weeks. The behavioral evaluation for induction of OA used the number of rears method, and this was conducted at 1, 2, and 4 weeks post-surgery. Bone mineral density (BMD) was calculated with micro-computerized tomography images and the modified Mankin's scoring was used for the histological changes. Results The number of rears in the OVX plus ACLT with MM group decreased gradually and more rapidly in the ACLT with MM group. Histologically, the OVX plus ACLT with MM group had a significantly higher modified Mankin's score than the OVX group (p=0.008) and the SHAM group (p=0.008). BMDs of the OVX plus ACLT with MM group were significantly lower than the SHAM group (p=0.002), and the ACLT with MM group (p=0.003). Conclusion We found that bilateral OVX plus ACLT with MM induced definite OA change in terms of histology and BMD compared to bilateral OVX and ACLT with MM alone. Therefore, OVX and ACLT with MM was an appropriate degenerative OA rat model. PMID:27606264

  17. Meniscal repair following meniscectomy: mechanism and protective effect. Experimental study in the dog.

    PubMed

    Berjon, J J; Munuera, L; Calvo, M

    1990-01-01

    Meniscal repair was studied to evaluate the mechanism and its potential protective effects on the articular cartilage in an experimental model consisting of 68 knees of adult dogs on which five different types of medial meniscectomy were performed. The results were assessed by macroscopic, microangiographic, and histological methods, after a sequential follow-up period of 10-450 days. Two different mechanisms of meniscal repair were observed, depending on whether meniscal section had been performed in vascular (total meniscectomy) or avascular (subtotal or partial meniscectomy) zones. It was also observed that the repaired meniscal tissue does not prevent articular cartilage degeneration. This is more closely related to the size of the meniscal fragment preserved at meniscectomy. Due to the biomechanical importance of the meniscus and the lack of functional relevance of the repaired meniscal tissue, the most conservative approach possible to meniscectomy is recommended. PMID:1703666

  18. Editorial Commentary: Book? … Book Report? … or Just a New Chapter in an Ongoing Story?: Knee Partial Meniscectomy Has Limited Benefit for "Nonobstructive" Meniscal Tears, but We Need to Know if Patients Have Osteoarthritis.

    PubMed

    Whelan, Daniel B

    2016-09-01

    Knee partial meniscectomy has limited benefit for "nonobstructive" meniscal tears, but we need to know if included patients have osteoarthritis. Research on outcomes of arthroscopic partial meniscectomy versus nonsurgical treatment must consider not only signs and symptoms but also imaging findings, to determine the indications for surgical versus nonsurgical in a selected patient. PMID:27594333

  19. Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle aged patients: randomised controlled trial with two year follow-up

    PubMed Central

    Risberg, May Arna; Stensrud, Silje; Ranstam, Jonas; Engebretsen, Lars; Roos, Ewa M

    2016-01-01

    Objective To determine if exercise therapy is superior to arthroscopic partial meniscectomy for knee function in middle aged patients with degenerative meniscal tears. Design Randomised controlled superiority trial. Setting Orthopaedic departments at two public hospitals and two physiotherapy clinics in Norway. Participants 140 adults, mean age 49.5 years (range 35.7-59.9), with degenerative medial meniscal tear verified by magnetic resonance imaging. 96% had no definitive radiographic evidence of osteoarthritis. Interventions 12 week supervised exercise therapy alone or arthroscopic partial meniscectomy alone. Main outcome measures Intention to treat analysis of between group difference in change in knee injury and osteoarthritis outcome score (KOOS4), defined a priori as the mean score for four of five KOOS subscale scores (pain, other symptoms, function in sport and recreation, and knee related quality of life) from baseline to two year follow-up and change in thigh muscle strength from baseline to three months. Results No clinically relevant difference was found between the two groups in change in KOOS4 at two years (0.9 points, 95% confidence interval −4.3 to 6.1; P=0.72). At three months, muscle strength had improved in the exercise group (P≤0.004). No serious adverse events occurred in either group during the two year follow-up. 19% of the participants allocated to exercise therapy crossed over to surgery during the two year follow-up, with no additional benefit. Conclusion The observed difference in treatment effect was minute after two years of follow-up, and the trial’s inferential uncertainty was sufficiently small to exclude clinically relevant differences. Exercise therapy showed positive effects over surgery in improving thigh muscle strength, at least in the short term. Our results should encourage clinicians and middle aged patients with degenerative meniscal tear and no definitive radiographic evidence of osteoarthritis to consider

  20. In vitro analysis of laser meniscectomy.

    PubMed

    Vangsness, C T; Akl, Y; Nelson, S J; Liaw, L H; Smith, C F; Marshall, G J

    1995-01-01

    Partial meniscectomies were performed on 32 fresh human meniscal autopsy specimens. The following laser systems were tested: carbon dioxide (CO2), neodymium:yttrium aluminum garnet (Nd:YAG), potassium titanyl phosphate (KTP), holmium:YAG (Ho:YAG), and excimer. Meniscectomies with these lasers were compared with scalpel, mechanical, and electrocautery meniscectomies. Lasers were applied to specimens in and out of normal saline. Routine hematoxylin and eosin and sirius red sections were prepared for each specimen, and the depths of thermal changes were analyzed. Scanning electron microscopy was used to visualize the meniscectomy interface. Among these specimens, the scalpel and mechanical meniscectomies showed the least extension of cellular changes (range, 10-15 nm). The excimer laser caused the least tissue changes of the lasers tested. Tissue changes were less extensive with the pulsed CO2 laser than with the holmium:YAG, neodymium:YAG, and KTP lasers. Scanning electron microscopy showed that use of the scalpel meniscectomy resulted in the smoothest meniscectomy edge, followed by use of the excimer, CO2, holmium:YAG, neodymium:YAG, and KTP lasers. The most surface disruption occurred with electrocautery. Meniscectomies under saline required more energy and took longer in each case, with the holmium:YAG, neodymium:YAG, and CO2 laser cutting the best. Saline meniscectomies showed less thermal change. The CO2 and KTP lasers cut best in air. PMID:7641441

  1. Evaluation of small intestinal submucosa grafts for meniscal regeneration in a clinically relevant posterior meniscectomy model in dogs.

    PubMed

    Cook, James L; Fox, Derek B; Malaviya, Prasanna; Tomlinson, James L; Farr, Jack; Kuroki, Keiichi; Cook, Cristi Reeves

    2006-07-01

    Large meniscal defects are a common problem for which treatment options are limited. Successful meniscal regeneration has been achieved by using grafts of small intestinal submucosa in posterior, vascular meniscal defects in a dog model. This study investigates the long-term effects of a tibial tunnel fixation technique and a clinically based meniscectomy defect on meniscal regeneration using this model. Eight mongrel dogs underwent medial arthrotomy and partial meniscectomy. The dogs were divided into groups based on defect treatment: small intestinal submucosa (n = 4) or meniscectomy (n = 4). Dogs were scored for lameness by subjective scoring postoperatively, sacrificed at 6 months, and assessed for articular cartilage damage, gross and histologic appearance of the operated meniscus, amount of new tissue in the defect, and relative compressive stiffness of articular cartilage. Dogs in the meniscectomy group were significantly (P = .002) more lame than dogs treated with small intestinal submucosa. Small intestinal submucosa-treated joints had significantly (P = .01) less articular cartilage damage than meniscectomy joints. Small intestinal submucosa meniscal implants resulted in production of meniscal-like replacement tissue, which was consistently superior to meniscectomy in amount, type, and integration of new tissue, chondroprotection, and limb function during the study period. Small intestinal submucosa implants may be useful for treatment of large posterior vascular meniscal defects in humans. The tibial tunnel technique used for fixation may have clinical advantages and therefore warrants further investigation. PMID:16893153

  2. 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

  3. The influence of synovial inflammation and hyperplasia on symptomatic outcomes up to two-years post-operatively in patients undergoing partial meniscectomy

    PubMed Central

    Scanzello, Carla R.; Albert, Anthony S.; DiCarlo, Edward; Rajan, Kumar B.; Kanda, Veero; Asomugha, Eva U.; Swaim, Bryan H.; Katz, Jeffrey N.; Goldring, Steven R.; Richmond, John C.; McKeon, Brian

    2013-01-01

    Objective Synovitis is associated with pain and other symptoms in patients with knee OA, and in patients with meniscal tears even in the absence of radiographic OA. Patients undergoing arthroscopic partial meniscectomy were followed for 2 years to determine whether synovitis predicts post-operative symptoms. Design Thirty-three patients scheduled for arthroscopy were recruited for this pilot study. Symptoms were assessed using a knee pain scale, the Lysholm score, and the SF-12® pre-operatively and at 16 weeks, 1 year and 2 years post-operatively. Synovial inflammation and hyperplasia were graded on surgical biopsies. Linear mixed effects models were tested to determine whether inflammation or hyperplasia is associated with outcome scores over time. Results Lysholm scores and SF-12® physical component sub-scores were worse pre-operatively in patients with inflammation (Lysholm: 52.42 [95%CI 42.37,62.47] vs. 72.38 [66.03,78.72], p<0.001; SF-12: 36.81 [28.26,45.37] vs 46.23 [40.14,52.32], p<0.05). Up to two-years post- operatively, patients with inflammation achieved mean scores similar to those without inflammation. As a result, the mean improvement in Lysholm scores was 13.01 [1.48–24.53] points higher than patients without inflammation, p = 0.03. 33% (4/12) of patients with inflammation still had fair-to-poor Lysholm scores two years after surgery compared to 7% (1/15, (p=0.14) without inflammation. No association between hyperplasia and symptoms was noted. Conclusions In this pilot study of patients undergoing partial meniscectomy, synovial inflammation was associated with worse pre-operative symptoms, but not with poorer outcomes in the first two years post-arthroscopy. Larger cohorts and longer follow-up should be pursued to confirm this relationship, and determine if the initial response is sustained. PMID:23973154

  4. Finnish Degenerative Meniscal Lesion Study (FIDELITY): a protocol for a randomised, placebo surgery controlled trial on the efficacy of arthroscopic partial meniscectomy for patients with degenerative meniscus injury with a novel ‘RCT within-a-cohort’ study design

    PubMed Central

    Sihvonen, Raine; Paavola, Mika; Malmivaara, Antti; Järvinen, Teppo L N

    2013-01-01

    Introduction Arthroscopic partial meniscectomy (APM) to treat degenerative meniscus injury is the most common orthopaedic procedure. However, valid evidence of the efficacy of APM is lacking. Controlling for the placebo effect of any medical intervention is important, but seems particularly pertinent for the assessment of APM, as the symptoms commonly attributed to a degenerative meniscal injury (medial joint line symptoms and perceived disability) are subjective and display considerable fluctuation, and accordingly difficult to gauge objectively. Methods and analysis A multicentre, parallel randomised, placebo surgery controlled trial is being carried out to assess the efficacy of APM for patients from 35 to 65 years of age with a degenerative meniscus injury. Patients with degenerative medial meniscus tear and medial joint line symptoms, without clinical or radiographic osteoarthritis of the index knee, were enrolled and then randomly assigned (1 : 1) to either APM or diagnostic arthroscopy (placebo surgery). Patients are followed up for 12 months. According to the prior power calculation, 140 patients were randomised. The two randomised patient groups will be compared at 12 months with intention-to-treat analysis. To safeguard against bias, patients, healthcare providers, data collectors, data analysts, outcome adjudicators and the researchers interpreting the findings will be blind to the patients’ interventions (APM/placebo). Primary outcomes are Lysholm knee score (a generic knee instrument), knee pain (using a numerical rating scale), and WOMET score (a disease-specific, health-related quality of life index). The secondary outcome is 15D (a generic quality of life instrument). Further, in one of the five centres recruiting patients for the randomised controlled trial (RCT), all patients scheduled for knee arthroscopy due to a degenerative meniscus injury are prospectively followed up using the same protocol as in the RCT to provide an external

  5. Results of meniscectomy and meniscal repair in anterior cruciate ligament reconstruction

    PubMed Central

    DELEDDA, DAVIDE; ROSSO, FEDERICA; COTTINO, UMBERTO; BONASIA, DAVIDE EDOARDO; ROSSI, ROBERTO

    2015-01-01

    Meniscal tears are commonly associated with anterior cruciate ligament (ACL) injuries. A deficient medial meniscus results in knee instability and could lead to higher stress forces on the ACL reconstruction. Comparison of results in meniscectomy and meniscal repairs revealed worse clinical outcomes in meniscectomy, but higher re-operation rates in meniscal repairs. Our aim was to review the results of ACL reconstruction associated with meniscectomy or meniscal repair. PMID:26889472

  6. Effects of arthroscopic meniscectomy on the long-term prognosis for the discoid lateral meniscus.

    PubMed

    Kim, Sung-Jae; Chun, Yong-Min; Jeong, Jae-Hoon; Ryu, Sang-Wook; Oh, Kyung-Soo; Lubis, Andri M T

    2007-11-01

    This study compared the long-term clinical and radiological outcomes, according to the extent of arthroscopic meniscectomy, of complete and incomplete types of the discoid lateral meniscus. A total of 125 discoid menisci (74 complete and 51 incomplete types) without significant cartilage erosion at the time of surgery were included. The extent of meniscectomy was decided along with tear patterns and the stability of the discoid meniscus. Both clinical and radiological results were evaluated after total or partial meniscectomy. In the complete type of discoid meniscus with less than 5 years of follow-up, the total meniscectomy group showed better clinical results than the partial meniscectomy group. However, with over 5 years of follow-up, there were no differences between the two groups. In the radiological results, there was no significant difference between the two groups during the first 5 years after operation. However, with more than 5 years of follow-up, the partial meniscectomy group showed better results than the total meniscectomy group. In the incomplete-type discoid meniscus, clinical results were better in the partial meniscectomy group regardless of the follow-up periods. In the radiological results, the partial meniscectomy group showed better results for only more than 5 years of follow-up. The long-term prognosis after arthroscopic meniscectomy for the torn discoid lateral meniscus was related to the volume of the meniscus removed. PMID:17762931

  7. Unusual Appearance of an Osteochondral Lesion Accompanying Medial Meniscus Injury

    PubMed Central

    Mine, Takatomo; Ihara, Koichiro; Kawamura, Hiroyuki; Date, Ryo; Chagawa, Kazuki

    2014-01-01

    An osteochondral lesion in the knee joint is caused by a focal traumatic osteochondral defect, osteochondritis dissecans, an isolated degenerative lesion, or diffuse degenerative disease. An osteochondral lesion with a cleft-like appearance accompanying medial meniscus injury is rare without trauma. We report the case of a 13-year-old boy who complained of right knee pain and swelling, with radiographic findings of an osteochondral defect. Arthroscopic inspection showed an osteochondral lesion in the medial condyle of the femur and tibial plateau accompanying a partial medial meniscus discoid tear. Partial meniscectomy was performed, and a microfracture procedure was carried out on the osteochondral defect. The patient was asymptomatic at 2 years' follow-up. This technique is a relatively easy, completely arthroscopic procedure that spares the bone and cartilage and has yielded a good clinical outcome in a skeletally immature patient who had an osteochondral lesion with a cleft-like appearance. PMID:24749028

  8. Bilateral Symptomatic Discoid Medial Meniscus of the Knee: A Case Report and Review of Literature

    PubMed Central

    Kini, Sunil Gurpur; Walker, Peter; Bruce, Warwick

    2015-01-01

    Introduction: A discoid medial meniscus is a rare pathology of the knee joint, and is even rarer when it presents bilaterally with clinical symptoms. Case Presentation: We present the case of a 38-year-old female with symptomatic bilateral discoid medial meniscus. Magnetic Resonance Imaging (MRI) showed complete discoid meniscus in one knee and incomplete, on the other side. The MRI findings were confirmed on arthroscopy, with horizontal cleavage tear in both knees. Arthroscopic partial meniscectomies of both menisci were performed. Conclusions: The patient had an excellent functional outcome at the most recent follow-up, with no recurrence of symptoms and full range of movements. PMID:25834792

  9. Transosseous Medial Meniscal Root Repair Using a Modified Mason-Allen Suture Configuration.

    PubMed

    Lavender, Chad D; Hanzlik, Shane R; Caldwell, Paul E; Pearson, Sara E

    2015-12-01

    Medial meniscal tears are among the most common injuries to the knee joint. Loss of the meniscus has been linked to increased contact pressures on the adjacent articular cartilage and progression of degenerative changes in the knee. A subset of tears known as "root tears" involves the insertion of the posterior horn of the meniscus to the bone. Arthroscopic partial meniscectomy for root tears led to undesirable outcomes, which prompted surgeons to explore restorative procedures. Multiple repair techniques have been presented with an emphasis placed on initial secure fixation and stimulation of potential healing. We present an arthroscopic-assisted technique for medial meniscal root repair with these goals in mind. PMID:27284511

  10. Return to sport after arthroscopic meniscectomy on stable knees

    PubMed Central

    2013-01-01

    Background Athletes suffering from any injuries want to know when they will be able to return sports activity. The period of return-to-sport after the arthroscopic meniscectomy is still unknown. The aim of this study is to investigate the period of the return-to-sport from surgery and the clinical symptoms after the meniscectomy on stable knees. Methods Fifty-six athletes who underwent the arthroscopic meniscectomy were evaluated. The patients with an average age of 26.7 years (range, 13–67) comprised 45 men and 11 women, 16 medial meniscus and 40 lateral meniscus injuries. The average of the follow-up period was 9.2 months. The parameter examined were age, the injured side of meniscus (medial or lateral), articular cartilage status, amount of resection, and sports activity level. Results The mean period was 54 days in young group, and was 89 days in old group (p = 0.0013). The period was 79 days in medial meniscus (MM) injured group, and was 61 days in lateral meniscus (LM) group (p = 0.017). There was a significant difference among the groups in activity levels and in amount of resection. Pain and/or effusion in the knee after the return-to-sport were found 22% of the MM group and 53% in the LM group. Conclusions The period of the return-to-sport was shorter in young age, high activity and large amount of resection group. Although athletes in LM group can return to sports earlier than those in MM group, more than half of athletes have pain or effusion at the time of return-to sport. PMID:24257295

  11. Degenerative lesions in the articular cartilage after meniscectomy: preliminary experimental study in dogs.

    PubMed

    Berjon, J J; Munuera, L; Calvo, M

    1991-03-01

    Articular cartilage degeneration was studied in an experimental model including 68 knees of adult dogs on which five different types of medial meniscectomy had been performed with a followup period of 10 to 450 days. The results were assessed by macroscopic, radiologic, and histologic methods. The degenerative lesions increased proportionally to the amount of meniscal tissue resected and the duration of observation. These lesions proved to be more intense at the tibial plateau compared to the femoral condyle. For both joint surfaces the predominant location was the central zone. Considering the degenerative process by the articular cartilage after total meniscectomy, maximum preservation of meniscal tissue is recommended. PMID:2002520

  12. Landing adaptations following isolated lateral meniscectomy in athletes

    PubMed Central

    Minning, Stephen J.; Myer, Gregory D.; Mangine, Robert E.; Colosimo, Angelo J.; Hewett, Timothy E.

    2014-01-01

    Purpose Objective functional outcomes following isolated radial lateral meniscus tears in the athlete between the ages of 14–25 are not clearly defined. The objective of this study was to determine whether patients following lateral meniscectomy demonstrate lower extremity asymmetries relative to control athletes 3 months after surgery. We hypothesized that following lateral meniscectomy, athletes aged 14–25 years old would demonstrate altered landing biomechanics compared to sex, age, height, weight, and sport-matched controls. Methods A total of 18 subjects were included in this study. Nine patients (7 men and 2 women, 20.1 ± 2.8 years) who had undergone first-time isolated radial lateral meniscus tears were tested 3 months following partial lateral meniscectomies and compared to nine sex, age, height, weight, and sport-matched controls (7 men and 2 women, 19.7 ± 3.1 years). A ten-camera motion analysis system and two force platforms were used to collect three trials of bilateral drop landings. A 2X2 ANOVA was used to test the interaction between side (involved vs. uninvolved) and group (patient vs. control). Results The patient group landed with a decreased internal knee extensor moment compared to the uninvolved side and controls (interaction P < 0.05). The involved limb quadriceps isokinetic torque was not decreased compared to the contralateral or control (n.s.). Decreased knee extensor moments were significantly associated with reduced measures of function (IKDC scores: r = 0.69; P < 0.05). Conclusions Athletes who return to sport at approximately 3 months following a partial lateral meniscectomy may employ compensation strategies during landing as evidenced by reduced quadriceps recruitment and functional outcome scores. Clinicians should focus on improving quadriceps function during landing on the involved leg in an attempt to decrease residual limb asymmetries. Level of evidence Case–control study, Level III. PMID:21468616

  13. Discoid medial meniscus. Varied presentation of 3 knees.

    PubMed

    Vidyadhara, S; Rao, Sharath K; Rao, Sripathi

    2006-06-01

    Discoid medial meniscus is a rarity. We present 2 cases, one with bilateral discoid medial menisci, and the other with both medial and lateral discoid menisci in the same knee. The radiological, MRI and arthroscopic findings in these knees and their association with various synovial plicae have been described. Both patients had good results after arthroscopic subtotal meniscectomy. PMID:16758058

  14. A RANDOMIZED TRIAL OF ISOKINETIC VERSUS ISOTONIC REHABILITATION PROGRAM AFTER ARTHROSCOPIC MENISCECTOMY

    PubMed Central

    Koutras, Georgios; Letsi, Magdalini; Papadopoulos, Pericles; Gigis, Ioannis

    2012-01-01

    Background: Although both isotonic and isokinetic exercises are commonly used in the rehabilitation of patients after arthroscopic meniscectomy no studies have compared their effect on strength recovery and functional outcomes. Purpose: The purpose of this study was to investigate the effects of two rehabilitation programs (isotonic and isokinetic) on muscle strength and functional performance after partial knee meniscectomy. A secondary purpose was to assess the correlation between isokinetic strength deficits and hop test performance deficits. Methods: Twenty male patients who underwent arthroscopic partial meniscectomy volunteered for the study. Both isotonic and isokinetic training were performed with the same equipment thereby blinding subjects to the mode of exercise. Main outcome measures were collected on the 14th and 33rd postoperative days and included isokinetic strength of the knee extensors and flexors, functional performance (single, triple, and vertical hopping) and the Lysholm questionnaire. Multivariate and univariate analyses of variance were used to assess the effects of the independent variables on the isokinetic variables, functional tests, and Lysholm score. Pearson's correlation was used to assess the relationship between isokinetic strength deficits and functional performance deficits. Results: Isokinetic measures, functional tests, and the Lysholm score all increased between initial and final assessment (p≤0.003). However, there were no group or group*time effects on any of the outcome variables (p≥0.33). Functional tests were better predictors of isokinetic deficits in the 14th compared to the 33rd postoperative day. Conclusion: No differences were found in the outcomes of patients treated using an isokinetic and an isotonic protocol for rehabilitation after arthroscopic meniscectomy. More than half of patients did not meet the 90% criterion in the hop tests for safe return to sports five weeks after meniscectomy. There were

  15. Anomalous insertion of the medial menisci.

    PubMed

    Jung, Y B; Yum, J K; Bae, Y J; Song, K S

    1998-01-01

    Many types of meniscal anomalies have been reported. The authors encountered two cases of anomalous insertion of the anterior horn of the medial menisci to the lateral femoral condyle, which ran up along the course of the anterior cruciate ligament (ACL), but was independent of the ACL. These anomalies were noted during arthroscopic examination and surgery of the ipsilateral knee for a torn discoid meniscus and a patellar fracture. A 34-year-old woman had a horizontal tear of the lateral discoid meniscus. We performed arthroscopic partial meniscectomy of the inner torn portion of the lateral discoid meniscus and contoured it to resemble a normal meniscus. An anomalous insertion of the medial meniscus was found on examination of the joint during surgery. A 32-year-old man had a patellar fracture and we performed reduction under arthroscopy and internal fixation with cannulated screws. The same anomalous insertion of the medial meniscus was also found on examination of the joint during surgery. We report the cases with a review of the literature. PMID:9681544

  16. Medial and lateral discoid menisci: a case report.

    PubMed

    Kim, Sung-Jae; Lubis, Andri Mt

    2010-01-01

    Discoid menisci on both medial and lateral tibial plateau are very rare abnormalities. We report a 44-year-old woman with bilateral medial and lateral discoid menisci. She also had anomalous insertion of discoid medial meniscus to anterior cruciate ligament, and pathologic medial patellar plica on the right knee. Meniscectomies has been performed for her torn discoid menisci with satisfactory result on the latest follow-up. PMID:20731824

  17. Medial and lateral discoid menisci: a case report

    PubMed Central

    2010-01-01

    Discoid menisci on both medial and lateral tibial plateau are very rare abnormalities. We report a 44-year-old woman with bilateral medial and lateral discoid menisci. She also had anomalous insertion of discoid medial meniscus to anterior cruciate ligament, and pathologic medial patellar plica on the right knee. Meniscectomies has been performed for her torn discoid menisci with satisfactory result on the latest follow-up. PMID:20731824

  18. Protease inhibitors decrease rabbit cartilage degradation after meniscectomy

    SciTech Connect

    Caputo, C.B.; Sygowski, L.A.; Patton, S.P.; Wolanin, D.J.; Shaw, A.; Roberts, R.A.; DiPasquale, G.

    1988-01-01

    In vitro proteoglycan (PG) synthesis and release were measured on cartilage removed from rabbit knees within 1 week of meniscectomy. Three days following partial lateral meniscectomy, 72% of the femurs and 82% of the tibias had visible ulcers. Cartilage from the weight-bearing areas incorporated 2.0-2.9 times more /sup 35/S-sulfate in vitro than cartilage from the opposite, unoperated knees. /sup 3/H-thymidine incorporation was 2.5-3.4 times higher for surgical than control groups. /sup 35/S-sulfate incorporation by the surgical group was inhibited by 22% in the presence of 10(-4) M U24522, an inhibitor of rabbit chondrocyte metalloprotease (CMP). /sup 3/H-thymidine incorporation by the surgical group was inhibited by 28% by 10(-4) M U24522. In vitro PG release from cartilage removed 2 days after surgery was 1.6-3.7 times higher for the surgical than the control group. PG release by the surgical group after 22 h of incubation was reduced to the control level by three CMP inhibitors, U24278, U24279, and U24522. PG release by cartilage from the nonsurgical group was also reduced by these compounds at 22 h. These results suggest that both the anabolic and catabolic processes that are stimulated by surgery can be isolated in vitro and that CMP may be involved in the catabolic process.

  19. Arthroscopic laser meniscectomy in a gas medium.

    PubMed

    Whipple, T L; Caspari, R B; Meyers, J F

    1985-01-01

    Laboratory investigations demonstrate the theoretical feasibility of utilizing CO2 laser energy for arthroscopic resection of the knee meniscus. Infrared light of 10.6 micron wavelength is sufficiently absorbed by fibrocartilage with byproducts of heat, water vapor, and a small residue of carbon ash. The remaining meniscus rim demonstrates viable chondrocytes in close proximity to the margin of resection, and gross collagen fiber architecture is preserved. The depth of penetration of the laser beam can be controlled by limiting the duration of exposure. Arthroscopic application of CO2 laser energy requires a gas medium. Carbon dioxide and nitrogen have proven to be satisfactory insufflation agents, with no lasting untoward effects noted in a clinical series of diagnostic arthroscopic procedures. The cost of laser generators and the lack of an ideal delivery system are limiting factors in clinical applications of this cutting mode for meniscectomy. PMID:3937537

  20. Controversial role of arthroscopic meniscectomy of the knee: A review.

    PubMed

    Ha, Austin Y; Shalvoy, Robert M; Voisinet, Anne; Racine, Jennifer; Aaron, Roy K

    2016-05-18

    The role of arthroscopic partial meniscectomy (APM) in reducing pain and improving function in patients with meniscal tears remains controversial. Five recent high-quality randomized controlled trials (RCTs) compared non-operative management of meniscal tears to APM, with four showing no difference and one demonstrating superiority of APM. In this review, we examined the strengths and weaknesses of each of these RCTs, with particular attention to the occurrence of inadvertent biases. We also completed a quantitative analysis that compares treatment successes in each treatment arm, considering crossovers as treatment failures. Our analysis revealed that each study was an excellent attempt to compare APM with non-surgical treatment but suffered from selection, performance, detection, and/or transfer biases that reduce confidence in its conclusions. While the RCT remains the methodological gold standard for establishing treatment efficacy, the use of an RCT design does not in itself ensure internal or external validity. Furthermore, under our alternative analysis of treatment successes, two studies had significantly more treatment successes in the APM arm than the non-operative arm although original intention-to-treat analyses showed no difference between these two groups. Crossovers remain an important problem in surgical trials with no perfect analytical solution. With the studies available at present, no conclusion can be drawn concerning the optimal treatment modality for meniscal tears. Further work that minimizes significant biases and crossovers and incorporates sub-group and cost-benefit analyses may clarify therapeutic indications. PMID:27190756

  1. Controversial role of arthroscopic meniscectomy of the knee: A review

    PubMed Central

    Ha, Austin Y; Shalvoy, Robert M; Voisinet, Anne; Racine, Jennifer; Aaron, Roy K

    2016-01-01

    The role of arthroscopic partial meniscectomy (APM) in reducing pain and improving function in patients with meniscal tears remains controversial. Five recent high-quality randomized controlled trials (RCTs) compared non-operative management of meniscal tears to APM, with four showing no difference and one demonstrating superiority of APM. In this review, we examined the strengths and weaknesses of each of these RCTs, with particular attention to the occurrence of inadvertent biases. We also completed a quantitative analysis that compares treatment successes in each treatment arm, considering crossovers as treatment failures. Our analysis revealed that each study was an excellent attempt to compare APM with non-surgical treatment but suffered from selection, performance, detection, and/or transfer biases that reduce confidence in its conclusions. While the RCT remains the methodological gold standard for establishing treatment efficacy, the use of an RCT design does not in itself ensure internal or external validity. Furthermore, under our alternative analysis of treatment successes, two studies had significantly more treatment successes in the APM arm than the non-operative arm although original intention-to-treat analyses showed no difference between these two groups. Crossovers remain an important problem in surgical trials with no perfect analytical solution. With the studies available at present, no conclusion can be drawn concerning the optimal treatment modality for meniscal tears. Further work that minimizes significant biases and crossovers and incorporates sub-group and cost-benefit analyses may clarify therapeutic indications. PMID:27190756

  2. ‘Not Always a Baker’s Cyst’ – An Unusual Presentation of a Central Voluminous Postero-Medial Meniscal Cyst

    PubMed Central

    Sivasubramanian, Harish; Ee, Gerard; Srinivasaiah, Manjunatha Ganiga; De, Shamal Das; Sing, AM

    2012-01-01

    Meniscal cysts are rare and often are a result of extrusion of synovial fluid through a tear of the meniscus, resulting in a one-way valve effect of the tear. Arthroscopic partial meniscectomy of the meniscus with intra-articular cyst drainage has become the standard of care. We report a case of an unusually large symptomatic medial meniscal cyst, situated postero-medially and pressing on the posterior cruciate ligament, which was initially clinically misdiagnosed as a Baker’s cyst. The patient had difficulty and pain on squatting. He was successfully treated with arthroscopic debridement and needle decompression; a rarity in literature for such a voluminous perilabral cyst tenting the posterior cruciate ligament. This procedure has the advantage of being able to obtain the cystic fluid for histological and cytological analysis before debridement. This case also highlights the importance of the use of Magnetic Resonance Imaging (MRI) to accurately diagnose a central, posterior knee swelling. PMID:23066435

  3. Future of 34 meniscectomies after bucket-handle meniscus tear: a retrospective study with a follow-up over 22 years.

    PubMed

    Vautrin, Matthias; Schwartz, Claude

    2016-05-01

    After a bucket-handle meniscus tear, a partial meniscectomy by arthroscopy is recommended, when a meniscal suture is impossible. Short-term results of meniscectomy after bucket-handle meniscus tear, without cartilage or ligament additional injury, are mostly excellent: pain and blocking disappear, return to sports activities is possible. The aim of this retrospective study is to follow a partial meniscectomy evolution with a long follow-up between March 1990 and April 1994, and a senior surgeon operated 34 meniscectomies for bucket-handle meniscus tear by 34 patients (29 male and 5 female) with a mean age of 31.7 years (16-52 years) at time of surgery. The bucket-handle meniscus tear had a traumatic etiology on a knee with no cartilage lesion. The functional results were assessed by IKDC subjective score (International Knee Documentation Committee) and ARPEGE score (Association pour la Recherche et la Promotion de l'Etude du Genou). These scores were obtained by phone call questionnaire in March 2014 with a mean follow-up of 22.7 years (20-24 years). In this study, patients were reviewed and got a clinical examination to determine the Lequesne score, a radiological knee assessment according to Ahlbäck classification and a weight-bearing teleradiography. With an IKDC mean score of 85.8 after surgery, we observed that 29 patients go back to sports activities with the same level as before injury. The level of sports activity, with a regular practice after a mean follow-up of 22.7 years, was the same as immediately after surgery or just the level under for 85.3 % of patients. With ARPEGE score, 48.5 % of patients had a global excellent result and 38.2 % had a global good result after a long follow-up. With a mean Lequesne score of 2.38, osteoarthritis of knee is still clinical minimal after meniscectomy at long term. The score was worse after external meniscectomy (EM) than after an internal meniscectomy (IM). 57.7 % of patients have osteoarthritis on X

  4. Patient Perception of Reimbursement for Arthroscopic Meniscectomy and ACL Reconstruction

    PubMed Central

    Okoroha, Kelechi; Keller, Robert A.; Marshall, Nathan E.; Guest, John-Michael; Lynch, Jonathan; Lock, Terrence R.; Rill, Brian K.

    2016-01-01

    Objectives: Healthcare policy changes and decreases in Medicare physician reimbursement continue to change the landscape of healthcare. Historically, patient perceptions of surgeon reimbursement have been exaggerated compared to actual reimbursement. Currently there is limited evidence for patient perception for arthroscopic meniscectomy and ACL reconstruction. The purpose of this study was to evaluate patient perception of physician reimbursement for arthroscopic meniscectomy and ACL reconstruction and to compare health care perceptions between urban and suburban clinics. Methods: Surveys were given to 231 consecutive patients, 127 in an urban clinic and 104 in a suburban clinic. Patients were asked their estimation of reasonable reimbursement for arthroscopic meniscectomy and ACL reconstruction as well as their perception on actual Medicare reimbursement to physicians. They were also asked how much would they be willing to pay out of pocket for the procedures. After revealing actual reimbursement rates, patients were asked if reimbursement levels were appropriate, whether surgeon subspecialty training was important, and if additional compensation should be associated with subspecialty training. Survey responses were compared with respondents in an urban versus a suburban setting as well as amongst income and education level. Results: Patients on average reported surgeons should receive $8,096 for a meniscectomy and $11,794 for an ACL reconstruction, 14 times and 11 times as much as actually reimbursed, respectively. Patients estimated that Medicare paid physicians $5,442 for a meniscectomy and $6,667 for an ACL reconstruction. Patients were willing to pay $2,286 out of pocket for a meniscectomy and $11,793 for an ACL reconstruction. Sixty five percent of patients believed reimbursement for meniscectomy was too low and 57% of patients believe reimbursement for ACL reconstruction was too low. Less than 2% of patients believed physician salaries should be cut

  5. Medial Meniscal Allograft Transplantation: The Bone Plug Technique.

    PubMed

    Dean, Chase S; Olivetto, Javier; Chahla, Jorge; Serra Cruz, Raphael; LaPrade, Robert F

    2016-04-01

    The medial meniscus is crucial for knee homeostasis. Treating patients who have undergone a subtotal or total meniscectomy, or equivalent irreparable tear pattern, can be extremely challenging, especially in young, active patients. The importance of meniscal preservation has been reported by several authors. Meniscal repair is now widely accepted as the first surgical option for treating medial meniscal tears. Moreover, current guidelines recommend preserving as much meniscal tissue as possible. Treating a symptomatic medial meniscectomized knee is challenging because of limited surgical options. In this context, medial meniscal allograft transplantation arises as the preferred procedure. The purpose of this article was to detail the arthroscopic medial meniscal allograft transplantation technique with the use of 2 bone plugs. PMID:27330948

  6. A partial lesion model of Parkinson's disease in mice--characterization of a 6-OHDA-induced medial forebrain bundle lesion.

    PubMed

    Boix, Jordi; Padel, Thomas; Paul, Gesine

    2015-05-01

    The most frequently used animal models for Parkinson's disease (PD) utilize unilateral injection of 6-hydroxydopamine (6-OHDA) in the medial forebrain bundle (MFB), which results in total denervation of the dopaminergic nigrostriatal pathway. However, neuroprotective interventions in PD require models resembling earlier stages of PD, where some dopaminergic cells and fibres remain. The aim of the present study was therefore to establish a MFB partial lesion model in mice. We tested four different 6-OHDA doses, and our results show a dose-dependent loss of nigral dopaminergic cells and striatal fibres that correlated with behavioural impairment in several behavioural tests. Specifically, doses of 0.7 μg and 1 μg of 6-OHDA induced a partial denervation of the nigrostriatal pathway, associated with a mild but quantifiable behavioural impairment. We identified the amphetamine-induced rotation, stepping, corridor and cylinder test to be sensitive enough to select partial lesion animals. Based on our data, we proposed a range of cut-off values for these different behavioural tests to select partial lesion mice. Using a statistical prediction model we identified two behavioural tests (the stepping test and amphetamine-induced rotation test) that with a high sensitivity and specificity predict the extent of nigral dopaminergic cell loss and select mice with a partial nigrostriatal lesion prior to further interventions. This model can serve as an important tool to study neuroprotective therapies for PD in mouse models, especially when the treatment targets the substantia nigra and/or the striatum. PMID:25698603

  7. Discoid medial meniscus completely coalesced with the anterior cruciate ligament.

    PubMed

    Joshi, Deepak; Jain, Vineet; Goyal, Ankit; Bahl, Vibhu; Chaudhary, Deepak

    2013-11-01

    Discoid meniscus is an abnormality of the knee in which the meniscus is discoid rather than semilunar in shape. Medial discoid menisci are rare, and no specific associated symptoms suggest this condition. Several medial meniscus anomalies, including discoid variants, have been reported in the literature. This article describes a rare case of medial discoid meniscus completely coalesced with the anterior cruciate ligament (ACL). A 22-year-old man presented with intermittent right knee pain of 6 months' duration. Physical examination revealed mild wasting of the quadriceps with medial joint line tenderness but no effusion. Radiographically, hypoplasia of the lateral tibial spine, increased medial joint space, and increased concavity of the medial tibial condyle were noted in both knees. Arthroscopic examination revealed a complete discoid medial meniscus that was contiguous with the ACL. On probing, a horizontal tear in the medial meniscus was noted. A meniscectomy was performed, and deep longitudinal furrows with exposed subchondral bone were noted underlying the posteromedial tibial condyle. At the patient's 6-month follow-up visit, he had no knee symptoms and had returned to his daily activities, which included jogging. Discoid medial meniscus is a rare anomaly, and this case represents only the second reported in the literature of discoid medial meniscus completely coalesced with ACL. This case supports the theory that the ACL and menisci can be differentiated from 1 mesenchyme. PMID:24200455

  8. Short-term clinical outcomes of 42 cases of arthroscopic meniscectomy for discoid lateral meniscus tears

    PubMed Central

    CAO, HONG; ZHANG, YING; QIAN, WEI; CHENG, XIN-HUA; KE, YONG; GUO, XIAO-PENG

    2012-01-01

    Discoid lateral meniscus of the knee causes a high morbidity in China. Since the traditional treatment to open the capsule and resect the meniscus often results in arthritis, it is now believed that a discoid lateral meniscus should be treated with arthroscopy to preserve part of the meniscus. The current study aimed to investigate the short-term clinical outcomes of arthroscopic meniscectomy for the treatment of discoid lateral meniscus tears. In the present study, we diagnosed and treated 42 patients (47 knees) with discoid lateral meniscus tears using arthroscopy between February, 2007 and December, 2010. Thirty-seven knees received partial resection of the discoid meniscus, 8 received hypo-complete resection and 2 received complete resection. Thirty-nine of the patients were followed up for a mean of 21 months (ranging from 9 to 53 months). The Lysholm scoring system was used to assess the knee function prior to surgery and during the follow-up. The results were analyzed using a Student’s t-test with SPSS 12.0. Our study showed that patients with treated knees returned to normal activities within 4–6 weeks, and knee functions were more improved at 9 months after operation than 3 months, as measured by the Lysholm score (P<0.05). Arthroscopic meniscectomy is an effective treatment for discoid menisci resulting in minimal invasion, quick recovery and early functional exercise. The use of arthroscopy during surgery aids to preserve the meniscus and to reduce stress, therefore, having a beneficial effect on short-term clinical outcomes. PMID:23226730

  9. Short-term clinical outcomes of 42 cases of arthroscopic meniscectomy for discoid lateral meniscus tears.

    PubMed

    Cao, Hong; Zhang, Ying; Qian, Wei; Cheng, Xin-Hua; Ke, Yong; Guo, Xiao-Peng

    2012-11-01

    Discoid lateral meniscus of the knee causes a high morbidity in China. Since the traditional treatment to open the capsule and resect the meniscus often results in arthritis, it is now believed that a discoid lateral meniscus should be treated with arthroscopy to preserve part of the meniscus. The current study aimed to investigate the short-term clinical outcomes of arthroscopic meniscectomy for the treatment of discoid lateral meniscus tears. In the present study, we diagnosed and treated 42 patients (47 knees) with discoid lateral meniscus tears using arthroscopy between February, 2007 and December, 2010. Thirty-seven knees received partial resection of the discoid meniscus, 8 received hypo-complete resection and 2 received complete resection. Thirty-nine of the patients were followed up for a mean of 21 months (ranging from 9 to 53 months). The Lysholm scoring system was used to assess the knee function prior to surgery and during the follow-up. The results were analyzed using a Student's t-test with SPSS 12.0. Our study showed that patients with treated knees returned to normal activities within 4-6 weeks, and knee functions were more improved at 9 months after operation than 3 months, as measured by the Lysholm score (P<0.05). Arthroscopic meniscectomy is an effective treatment for discoid menisci resulting in minimal invasion, quick recovery and early functional exercise. The use of arthroscopy during surgery aids to preserve the meniscus and to reduce stress, therefore, having a beneficial effect on short-term clinical outcomes. PMID:23226730

  10. Mid-term clinical results of medial meniscus repair with the meniscus arrow in the unstable knee.

    PubMed

    Koukoulias, Nikolaos; Papastergiou, Stergios; Kazakos, Konstantinos; Poulios, Georgios; Parisis, Konstantinos

    2007-02-01

    The medial meniscus is a secondary stabilizer to anterior tibial translation and provides significant stability, especially in an ACL-deficient knee. The purpose of this study is to evaluate the clinical outcome of medial meniscus repair in the unstable knee. Between 1997 and 2002, 11 patients, with a mean age of 25.8 years (range 15-39 years), underwent all-inside medial meniscus repair, using the Meniscus Arrow, for unstable medial meniscus tear in ACL-deficient knees. For various reasons none of these patients underwent ACL reconstruction. The average follow-up was 73 months (range 52-91 months). There were three failures (27.3%) defined as the need for reoperation and partial meniscectomy. The mean Tegner activity score decreased from 6.75 (pretrauma) to 4.5 (postoperatively). The average Lysholm and subjective IKDC scores were 83 and 77.4, respectively. Two patients were graded as B (nearly normal) and six as C (abnormal), according to the IKDC knee evaluation form. KT-2000 arthrometry demonstrated that sagittal knee laxity was more than 5 mm in all knees (side to side difference). MRI demonstrated grade three signal alterations at the repair site of meniscus in three patients and signs of cartilage damage in two patients. All patients were asymptomatic during daily activities but seven out of eight reported pain or effusion after sports. Medial meniscus repair in the ACL-deficient knee is not contraindicated. The need of reducing the level of physical activity is essential. PMID:16967201

  11. Treatment of elderly patients with advanced lipedema: a combination of laser-assisted liposuction, medial thigh lift, and lower partial abdominoplasty

    PubMed Central

    Wollina, Uwe; Heinig, Birgit; Nowak, Andreas

    2014-01-01

    Background Lipedema is a rare female disorder with a characteristic distribution of adipose tissue hypertrophy on the extremities, with pain and bruising. In advanced stages, reduction of adipose tissue is the only available effective treatment. In elderly patients with advanced lipedema, correction of increased skin laxity has to be considered for an optimal outcome. Methods We report on a tailored combined approach to improve advanced lipedema in elderly females with multiple comorbidities. Microcannular laser-assisted liposuction of the upper legs and knees is performed under tumescent anesthesia. Medial thigh lift and partial lower abdominoplasty with minimal undermining are used to correct skin laxity and prevent intertrigo. Postsurgical care with nonelastic flat knitted compression garments and manual lymph drainage are used. Results We report on three women aged 55–77 years with advanced lipedema of the legs and multiple comorbidities. Using this step-by-step approach, a short operation time and early mobilization were possible. Minor adverse effects were temporary methemoglobinemia after tumescent anesthesia and postsurgical pain. No severe adverse effects were seen. Patient satisfaction was high. Conclusion A tailored approach may be useful in advanced lipedema and is applicable even in elderly patients with multiple comorbidities. PMID:24489474

  12. Locked bucket-handle tears of both medial and lateral menisci with simultaneous anterior cruciate and medial collateral ligaments injury.

    PubMed

    Koukoulias, Nikolaos E; Kyparlis, Dimitris; Koumis, Panagiotis; Lola, Despoina; Papastergiou, Stergios G

    2011-01-01

    The authors report the case of a 38-year-old male who presented to the accident and emergency department with a locked knee after falling from a height. The knee was locked at 35° of flexion without any signs of instability in clinical examination. The patient was operated within 6 h from injury. During arthroscopy bucket-handle tears of both medial and lateral menisci were found. The bucket-handle fragments were displaced into the intercondylar notch causing the knee to lock. Additionally, tears of the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) were also found. The patient underwent ACL reconstruction with hamstrings autograft, medial subtotal meniscectomy and lateral meniscus repair. The MCL was treated conservatively. The postoperative period was uneventful and the patient returned to the preinjury level of activity within 8 months. The patient remains asymptomatic 2 years postoperatively. PMID:22691631

  13. Locked bucket-handle tears of both medial and lateral menisci with simultaneous anterior cruciate and medial collateral ligaments injury

    PubMed Central

    Koukoulias, Nikolaos E; Kyparlis, Dimitris; Koumis, Panagiotis; Lola, Despoina; Papastergiou, Stergios G

    2011-01-01

    The authors report the case of a 38-year-old male who presented to the accident and emergency department with a locked knee after falling from a height. The knee was locked at 35° of flexion without any signs of instability in clinical examination. The patient was operated within 6 h from injury. During arthroscopy bucket-handle tears of both medial and lateral menisci were found. The bucket-handle fragments were displaced into the intercondylar notch causing the knee to lock. Additionally, tears of the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) were also found. The patient underwent ACL reconstruction with hamstrings autograft, medial subtotal meniscectomy and lateral meniscus repair. The MCL was treated conservatively. The postoperative period was uneventful and the patient returned to the preinjury level of activity within 8 months. The patient remains asymptomatic 2 years postoperatively. PMID:22691631

  14. Cytotoxic lesion of the medial prefrontal cortex abolishes the partial reinforcement extinction effect, attenuates prepulse inhibition of the acoustic startle reflex and induces transient hyperlocomotion, while sparing spontaneous object recognition memory in the rat.

    PubMed

    Yee, B K

    2000-01-01

    The partial reinforcement extinction effect refers to the increase in resistance to extinction of an operant response acquired under partial reinforcement relative to that acquired under continuous reinforcement. Prepulse inhibition of the acoustic startle response refers to the reduction in startle reactivity towards an intense acoustic pulse stimulus when it is shortly preceded by a weak prepulse stimulus. These two behavioural phenomena appear to be related to different forms of attentional processes. While the prepulse inhibition effect reflects an inherent early attentional gating mechanism, the partial reinforcement extinction effect is believed to involve the development of acquired inattention, i.e. the latter requires the animals to learn about what to and what not to attend. Impairments in prepulse inhibition and the partial reinforcement extinction effect have been independently linked to the neuropsychology of attentional dysfunctions seen in schizophrenia. The proposed neural substrates underlying these behaviourial phenomena also appear to overlap considerably: both focus on the nucleus accumbens and emphasize the functional importance of its limbic afferents, including that originating from the medial prefrontal cortex, on accumbal output/activity. The present study demonstrated that cytotoxic medial prefrontal cortex lesions which typically damaged the prelimbic, the infralimbic and the dorsal anterior cingulate areas could lead to the abolition of the partial reinforcement extinction effect and the attenuation of prepulse inhibition. The lesions also resulted in a transient elevation of spontaneous locomotor activity. In contrast, the same lesions spared performance in a spontaneous object recognition memory test, in which the lesioned animals displayed normal preference for a novel object when the novel object was presented in conjunction with a familiar object seen 10 min earlier within an open field arena. The present results lend support to the

  15. Clinical Outcomes of Medial Meniscus Posterior Root Tears

    PubMed Central

    Krych, Aaron John; Reardon, Patrick J.; Pareek, Ayoosh; Peter, Logan; Dahm, Diane L.; Levy, Bruce A.; Stuart, Michael J.

    2016-01-01

    Objectives: Medial meniscus posterior root tears (MMPRTs) present a unique challenge for both patients and surgeons as these tears have shown to be biomechanically equivalent to complete meniscectomy. However, little is known about the natural history of these lesions. Therefore, the purpose of this study is to describe the clinical course of MMPRTs with respect to subsequent operative and non-operative treatments, and associated comorbidities. Methods: Over 2600 MRIs were identified by searching radiologist reads for the terms “root” or “root tear” from 2005-2013. Presence or absence of MMPRTs and other associated boney, meniscal, or ligamentous injuries were identified and recorded. Of these MRIs, 102 MRIs from 102 patients who had unrepaired MMPRTs with minimum 2-year follow-up and no prior ligamentous surgery were followed. These MRIs were evaluated to confirm the presence of a meniscal root tear and the presence or absence of associated meniscal or ligamentous injuries, as well as meniscal extrusion, subchondral edema, or insufficiency fractures. Chart review was performed to obtain the treatment summary after diagnosis. Radiographs from before and after the diagnosis of MMPRT were reviewed and Kellgren-Lawrence scores were determined. Finally, the association between concomitant boney, ligamentous, or meniscal injuries, patient factors, and rate of arthroplasty, as well as final Kellgren-Lawrence scores were evaluated. Chi-square analysis was used for categorical variables, and Wilcoxon Rank-Sums was used for continuous variables. Kaplan-Meier analysis was used to evaluate the effect of meniscal extrusion on the time-dependant rate of arthroplasty. Results: 104 patients (43 M:61F) were diagnosed with MMPRTs at a mean age of 54±13. These patients were followed for a mean of 66±26 months. 75 (74%) patients had associated meniscal extrusion, 64 (62%) had associated subchondral edema, and 14 (13%) had associated insufficiency fractures at the time of

  16. To Run or Not to Run: A Post-Meniscectomy Qualitative Risk Analysis Model for Osteoarthritis When Considering a Return to Recreational Running

    PubMed Central

    Baumgarten, Bob

    2007-01-01

    The increased likelihood of osteoarthritic change in the tibiofemoral joint following meniscectomy is well documented. This awareness often leads medical practitioners to advise patients previously engaged in recreational running who have undergone meniscectomy to cease all recreational running. This literature review examines the following questions: 1) Is there evidence to demonstrate that runners, post-meniscectomy, incur a great enough risk for early degenerative OA to cease all running? 2) Does the literature yield risk factors for early OA that would guide a physical therapist with regard to advising the post-meniscectomy patient contemplating a return to recreational running? Current literature related to meniscal structure and function, etiology and definition of osteoarthritis, methods for assessing osteoarthritis, relationship between running and osteoarthritis, and relationship between meniscectomy and osteoarthritis are reviewed. This review finds that while the probability for early osteoarthritis in the post-meniscectomy population is substantial, it is a probability and not a certainty. To help guide a physical therapist with regard to advising the patient for a safe return to running following a meniscectomy, a qualitative risk assessment based on identified risk factors for osteoarthritis in both the running and the post-meniscectomy populations is proposed. PMID:19125175

  17. Arthroscopic Medial Meniscus Posterior Root Fixation Using a Modified Mason-Allen Stitch.

    PubMed

    Chung, Kyu Sung; Ha, Jeong Ku; Ra, Ho Jong; Kim, Jin Goo

    2016-02-01

    A complete radial tear of the meniscus posterior root, which can effectively cause a state of total meniscectomy via loss of hoop tension, requires that the torn root be repaired. Several methods have been used to repair medial meniscus posterior root tears, most of which are based on a simple stitch technique that is known to have stitch-holding strength. We applied a modified version of the Mason-Allen stitch technique, which is recognized as a method for rotator cuff repair surgery because its locking effect overcomes the potential weakness of simple stitches. This article introduces the medial meniscus posterior root tears repair procedure based on a modified Mason-Allen stitch technique in which 2 strands (i.e., 1 simple horizontal and 1 simple vertical stitch) are used. PMID:27073778

  18. Arthroscopic Medial Meniscus Posterior Root Fixation Using a Modified Mason-Allen Stitch

    PubMed Central

    Chung, Kyu Sung; Ha, Jeong Ku; Ra, Ho Jong; Kim, Jin Goo

    2016-01-01

    A complete radial tear of the meniscus posterior root, which can effectively cause a state of total meniscectomy via loss of hoop tension, requires that the torn root be repaired. Several methods have been used to repair medial meniscus posterior root tears, most of which are based on a simple stitch technique that is known to have stitch-holding strength. We applied a modified version of the Mason-Allen stitch technique, which is recognized as a method for rotator cuff repair surgery because its locking effect overcomes the potential weakness of simple stitches. This article introduces the medial meniscus posterior root tears repair procedure based on a modified Mason-Allen stitch technique in which 2 strands (i.e., 1 simple horizontal and 1 simple vertical stitch) are used. PMID:27073778

  19. Significant synovial pathology in a meniscectomy model of osteoarthritis: modification by intra-articular hyaluronan therapy

    PubMed Central

    Cake, M. A.; Ghosh, P.; Schiavinato, A.; Read, R. A.; Little, C. B.

    2008-01-01

    Objective. IA therapy with hyaluronan (HA) is reported to provide symptomatic relief and disease modification in OA. This study assessed the pathological changes in the synovium of an ovine model of OA and evaluated the effects of two HA preparations on this pathology. Methods. Eighteen sheep had bilateral lateral meniscectomy to induce OA. Four months post-surgery animals received IA saline or HA (Hyalgan®) weekly for 5 weeks or three injections of an amide derivative of HA (HYADD®4-G) every 2 weeks (n = 6 per group). Six months after meniscectomy, sheep were killed, knee joint synovium processed, scored for pathological change and compared with synovium from non-operated animals. Sections of synovium from normal and treated joints were also immunostained for TNF-α, HSP-47, TGF-β, CD44, connective tissue growth factor (CTGF) or iNOS. HA synthesis by synovial fibroblasts isolated from each OA joint was quantified. Results. Aggregate scores of pathological change were higher in OA joint synovia compared with controls, with individual measures of subintimal fibrosis and vascularity predominantly affected. Depth of intimal fibrosis was also significantly higher in meniscectomized joints. IA treatment with Hyalgan® decreased aggregate score, vascularity and depth of fibrosis. HYADD®4-G treatment decreased vascularity, intimal hyperplasia and increased high-molecular weight HA synthesis by synovial fibroblasts. CD44, CTGF or iNOS expression was increased in the synovial lining of OA joints compared with normal, but there was no significant modulation of this increase by either HA preparation. Conclusion. Increased fibrosis and vascularity are hallmarks of pathological change in synovium in this meniscectomy model of OA. Both the IA HA and an amide derivative of HA reduced aspects of this pathology thus providing a potential mechanism for improving joint mobility and function in OA. PMID:18565987

  20. Posterolateral rotatory instability of the knee after arthroscopic subtotal lateral meniscectomy: a case report

    PubMed Central

    BULGHERONI, ERICA; BULGHERONI, PAOLO

    2014-01-01

    A 33-year-old Caucasian woman came to our attention complaining of lateral knee pain on the left side, severe external instability associated with varus malalignment, and difficulties in weight-bearing activities. The symptoms had appeared following two lateral meniscectomies on her discoid meniscus, performed elsewhere. The patient was initially submitted to an allograft meniscus transplantation exploiting the unloaded condition of lateral compartment and obtained pain relief. The posterolateral corner was reconstructed in combination with a valgus osteotomy to address the posterolateral rotatory instability. The follow-up assessment at two years after the last surgery showed no symptoms, maintenance of limb alignment and no evidence of joint degeneration. PMID:25606550

  1. Posterolateral rotatory instability of the knee after arthroscopic subtotal lateral meniscectomy: a case report.

    PubMed

    Bulgheroni, Erica; Bulgheroni, Paolo

    2014-01-01

    A 33-year-old Caucasian woman came to our attention complaining of lateral knee pain on the left side, severe external instability associated with varus malalignment, and difficulties in weight-bearing activities. The symptoms had appeared following two lateral meniscectomies on her discoid meniscus, performed elsewhere. The patient was initially submitted to an allograft meniscus transplantation exploiting the unloaded condition of lateral compartment and obtained pain relief. The posterolateral corner was reconstructed in combination with a valgus osteotomy to address the posterolateral rotatory instability. The follow-up assessment at two years after the last surgery showed no symptoms, maintenance of limb alignment and no evidence of joint degeneration. PMID:25606550

  2. Discoid medial meniscus.

    PubMed

    Tachibana, Yomei; Yamazaki, Yuji; Ninomiya, Setsuo

    2003-09-01

    A discoid medial meniscus is an extremely rare anomaly. We present 4 cases of symptomatic discoid medial meniscus. Furthermore, magnetic resonance imaging (MRI) of the unaffected knee was obtained in 3 cases, and 1 patient had bilateral discoid medial menisci as well as a unilateral discoid lateral meniscus proven by MRI. Another patient had bilateral discoid medial menisci. In one of the other 2 cases, an MRI of the unaffected knee was not obtained. However, in the involved knees of both cases, medial and lateral menisci were discoid. The incidence of bilateral discoid medial menisci is unknown. In the past, the diagnosis of a discoid meniscus was made with an arthrogram or at arthrotomy. Therefore, whether some of the unilateral cases reported in the literature might have been bilateral is unknown. The reported prevalence of bilateral discoid medial menisci will probably increase, because when a discoid medial meniscus is encountered currently, an MRI is used to find knee disorders, including in the contralateral knee. Axial multiplanar gradient-recalled-echo imaging could provide images of the discoid meniscus, depicted in its entirety in one section. This would make the recognition of a discoid meniscus simple. PMID:12966402

  3. 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. PMID:27245491

  4. Chuave Medial Verbs

    ERIC Educational Resources Information Center

    Thurman, Robert C.

    1975-01-01

    This article discusses two syntactic processes known as chaining and linkage, insofar as they are relevant to Chuave, a Papuan language spoken in the East New Guinea Highlands. These processes are discussed in relation to Chuave medial verbs. (CLK)

  5. Arthroscopic contact Nd:YAG laser meniscectomy: basic science, surgical technique, and clinical follow up

    NASA Astrophysics Data System (ADS)

    O'Brien, Stephen J.; Fealy, Stephen V.; Gibney, Mary A.; Miller, Drew V.; Kelly, Anne M.

    1990-06-01

    Recent basic science studies (5) have provided a scientific foundation for the use of the Contact Nd:YAG Laser as an arthroscopic tool for xneniscal resection and acroxnioplasty of the shoulder in a saline medium. This study prospectively evaluates the results of a three stage laboratory investigation as well as the clinical results of arthroscopic xneniscal resection. Fifteen patients with meniscal tears underwent subtotal meniscectomies utilizing a Contact Nd:YAG Laser (Surgical Laser Technologies; Malvern, Pennsylvania) . This was done in a saline medium with an average laser wattage of 25 W, (range 20 W to 30 W). Patients were evaluated postoperatively with reference to subjective and objective parameters at one week and four weeks postoperatively. Patients were evaluated with regard to wound healing, intraarticular swelling and pain. Assessment of technical parameters such as ease of resection, time of resection and instrument access were compared to conventional instruments. All fifteen patients were rated as having clinically excellent results based on pain relief, wound healing and swelling. In addition, although there was increased time with setting up the laser and calibrating it, there was not an increase in time for meniscal resection. Little, or no, secondary "trimmuning" was necessary with the laser. Increased accessibility was noted due to the small size of the laser. Arthroscopic Contact Nd:YAG Laser surgery is a safe and effective tool for menisca]. resection and coagulation in arthroscopic acromioplasties. It provides significant advantages over conventional cutting instruments with regard to accessibility and reduced need for secondary instruments.

  6. The Trapped Medial Meniscus Tear

    PubMed Central

    Herschmiller, Thomas A.; Anderson, John A.; Garrett, William E.; Taylor, Dean C.

    2015-01-01

    Background: Numerous clinical examination maneuvers have been developed to identify meniscus tears of the knee. While meniscus injuries vary significantly in type and severity, no maneuvers have been developed that help to distinguish particular tear characteristics. Purpose: This nonconsecutive case series highlights a distinctive clinical finding that correlates with inferiorly displaced flap tears of the medial meniscus that become trapped in the medial gutter of the knee, as identified through magnetic resonance imaging (MRI) and arthroscopy. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Eight patients with trapped medial meniscus tears were identified from a single surgeon’s academic orthopaedic sports medicine practice between January 2009 and January 2012. Each patient underwent clinical evaluation, MRI, and arthroscopic treatment for meniscus injury. Clinical notes, MRI images, radiology reports, and operative findings were reviewed and compared in a descriptive fashion. Results: Each patient displayed a positive clinical examination finding of medial knee pain inferior to the joint line with flexion and the application of valgus stress in the setting of a torn medial meniscus and intact medial collateral ligament (MCL). Preoperative MRI revealed a distinctive flap tear of the medial meniscus flipped inferiorly to lay trapped between the tibia and deep fibers of the MCL. On arthroscopy, flap tears were found displaced inferiorly and trapped in the medial gutter in 6 of the 8 patients. Displaced meniscal fragments in the remaining 2 patients were found within the medial compartment. Conclusion: Inferiorly displaced flap tears of the meniscus that have been displaced to the medial gutter can be localized through a careful examination technique. Clinical Relevance: Early identification of this injury pattern may help reduce the likelihood that the trapped fragment will be missed during arthroscopy. PMID:26675499

  7. Medial Collateral Ligament (MCL) Injuries

    MedlinePlus

    ... often occur among active teens, especially athletes. A torn medial collateral ligament (MCL) — a ligament that helps ... the more serious injuries. Teens who have a torn MCL tend to play contact sports, like football ...

  8. Bilateral medial displacement of the biceps tendon of origin: repair using polypropylene mesh and staples.

    PubMed

    Barnes, D M

    2013-09-01

    A three-year-old male greyhound was presented with acute onset right forelimb lameness because of medial displacement of the biceps tendon of origin. Ultrasonographic examination confirmed the diagnosis, and a concomitant partial tear of the medial glenohumeral ligament was detected during arthroscopy. To stabilise the biceps tendon, polypropylene mesh was fixed across the intertubercular groove to replace the torn transverse humeral retinaculum. Recovery was uneventful and lameness resolved. Fifteen months later, the dog was presented with medial displacement of the biceps tendon of origin of the left shoulder, and was treated successfully using the same technique. PMID:23614688

  9. Medial Compartment Decompression by Fibular Osteotomy to Treat Medial Compartment Knee Osteoarthritis: A Pilot Study.

    PubMed

    Yang, Zong-You; Chen, Wei; Li, Cun-Xiang; Wang, Juan; Shao, De-Cheng; Hou, Zhi-Yong; Gao, Shi-Jun; Wang, Fei; Li, Ji-Dong; Hao, Jian-Dong; Chen, Bai-Cheng; Zhang, Ying-Ze

    2015-12-01

    Compared with high tibial osteotomy and total knee arthroplasty, the authors found a simpler surgical procedure, partial fibular osteotomy, could effectively relieve knee pain and also correct the varus deformity for patients with medial compartment knee osteoarthritis (OA). From January 1996 to April 2012, a total of 156 patients with medial compartment OA were treated by proximal fibular osteotomy in the authors' hospital. A 2-cm-long section of fibula was resected 6 to 10 cm below the fibular head. A total of 110 patients with follow-up of more than 2 years were included in the study, including 34 males and 76 females with an average age of 59.2 years. Anteroposterior and lateral weight-bearing radiographs, the femorotibial angle (FTA) and lateral joint space, and the American Knee Society Score (KSS) and the visual analog scale (VAS) score of the knee joint were evaluated preoperatively and at final follow-up, respectively. At final follow-up, mean FTA and lateral joint space were 179.4°±1.8° and 6.9±0.7 mm, respectively, which were significantly smaller than those measured preoperatively (182.7°±2.0° and 12.2±1.1 mm, respectively; both P<.001). Mean KSS at final follow-up was 92.3±31.7, significantly higher than the mean preoperative score of 45.0±21.3 (P<.001). Mean VAS score and interquartile range were 2.0 and 2.0, significantly lower than the preoperative data (7 and 1.0, respectively; P<.001). The authors found that proximal fibular osteotomy can significantly improve both the radiographic appearance and function of the affected knee joint and also achieve long-term pain relief. This procedure may be an alternative treatment option for medial compartment OA. PMID:26652332

  10. Spontaneous medial dislocation of the tendon of the long biceps brachii. An anatomic study of prevalence and pathomechanics.

    PubMed

    Petersson, C J

    1986-10-01

    Medial displacement of the tendon of the long biceps brachii muscle was analyzed in a dissection study on autopsy in 77 subjects, 42 men and 35 women. The tendon was found to be medially displaced in five shoulders in five different subjects (6.5%). Medial displacement of the tendon was always found in connection with full-thickness supraspinatus tendon ruptures. It is a common belief that the tendon is always displaced medially to the lesser tubercle riding over the subscapularis tendon. In the present series, this condition was found only in one case; in the other shoulders the tendon had slipped medially to the lesser tubercle under the subscapularis tendon, which was partially internally ruptured. In patients with rotator cuff lesions, medial displacement of the long biceps tendon might be one reason for pain over the front of the shoulder. PMID:3769261

  11. Acute and chronic response of meniscal fibrocartilage to holmium:YAG laser irradiation

    NASA Astrophysics Data System (ADS)

    Horan, Patrick J.; Popovic, Neven A.; Islinger, Richard B.; Kuklo, Timothy R.; Dick, Edward J.

    1997-05-01

    The acute and chronic (10 week) histological effects of the holmium:YAG laser during partial meniscectomy in an in vivo rabbit model were investigated. Twenty-four adult male New Zealand rabbits underwent bilateral parapatellar medial knee arthrotomies. In the right knee, a partial medial meniscectomy was done through the avascular zone using a standard surgical blade. In the left knee, an anatomically similar partial medial meniscectomy was performed using a Ho:YAG laser (Coherent, USA). This study indicates that the laser creates two zones of damage in the meniscal fibrocartilage and that the zone of thermal change may act as a barrier to healing. The zone of thermal change which is eventually debrided was thought at the time of surgery to be viable. In the laser cut menisci, the synovium appears to have greater inflammation early and to be equivalent with the scalpel cut after three weeks. At all time periods there appeared more cellular damage in the laser specimens.

  12. Minimally invasive medial hip approach.

    PubMed

    Chiron, P; Murgier, J; Cavaignac, E; Pailhé, R; Reina, N

    2014-10-01

    The medial approach to the hip via the adductors, as described by Ludloff or Ferguson, provides restricted visualization and incurs a risk of neurovascular lesion. We describe a minimally invasive medial hip approach providing broader exposure of extra- and intra-articular elements in a space free of neurovascular structures. With the lower limb in a "frog-leg" position, the skin incision follows the adductor longus for 6cm and then the aponeurosis is incised. A slide plane between all the adductors and the aponeurosis is easily released by blunt dissection, with no interposed neurovascular elements. This gives access to the lesser trochanter, psoas tendon and inferior sides of the femoral neck and head, anterior wall of the acetabulum and labrum. We report a series of 56 cases, with no major complications: this approach allows treatment of iliopsoas muscle lesions and resection or filling of benign tumors of the cervical region and enables intra-articular surgery (arthrolysis, resection of osteophytes or foreign bodies, labral suture). PMID:25164350

  13. Regeneration of ring-shaped lateral meniscus after partial resection of discoid meniscus with anterior cruciate ligament reconstruction☆

    PubMed Central

    Soejima, Takashi; Kanazawa, Tomonoshin; Tabuchi, Kousuke; Noguchi, Kouji; Inoue, Takashi; Murakami, Hidetaka

    2013-01-01

    INTRODUCTION The ring-shaped lateral meniscus is very rare. Although it is essentially known as a congenital anomaly, a central tear in an incomplete discoid meniscus or an old bucket-handle tear in a meniscus may be easily mistaken for a ring-shaped meniscus. We experienced a ring-shaped lateral meniscus that regenerated after partial resection of a discoid meniscus together with anterior cruciate ligament (ACL) reconstruction. PRESENTATION OF CASE A 37-year-old female patient still experienced unrelenting knee pain 6 months after ACL reconstruction and partial meniscectomy of a discoid lateral meniscus. A repeat arthroscopy was performed. The lateral tibial plateau was covered in the form of a ring by meniscus-like tissue. The meniscus-like tissue appeared to have regenerated inward toward the center from the stump after the partial meniscectomy and was connected from the anterior to posterior horn, forming an interhorn bridge. Partial meniscectomy was repeated. Histologically, the regenerated tissue was not meniscal, but comprised mature fibrocartilage; macroscopically; however, it was very similar to meniscal tissue. Two years after the initial operation, the patient had no complaints and experienced full return of function. DISCUSSION The reason for such regeneration is unknown, but may have been attributed to the specific intra-articular environment that developed after the ACL reconstruction. CONCLUSION This is the first report of regenerative development of a ring-shaped lateral meniscus. When a ring-shaped lateral meniscus is diagnosed, we must accurately determine whether it is a true congenital anomaly in consideration of the present case. PMID:24240076

  14. Return to Play After Medial Collateral Ligament Injury.

    PubMed

    Kim, Christopher; Chasse, Patrick M; Taylor, Dean C

    2016-10-01

    Medial collateral ligament injuries are common in the athletic population. Partial injuries are treated nonoperatively with excellent outcomes. Complete ruptures may be treated nonoperatively, although some will require surgery. A comprehensive rehabilitation program is critical to outcome, but a standardized program for all injuries does not exist. Most of the literature regarding nonoperative and postoperative rehabilitation include observational reports and case studies. Level I studies comparing rehabilitation protocols have not been published. The goal of the injured athlete is to not only return to play with no functional limitations, but to also address risk factors and prevent future injuries. PMID:27543407

  15. Bottom-up Visual Integration in the Medial Parietal Lobe.

    PubMed

    Pflugshaupt, Tobias; Nösberger, Myriam; Gutbrod, Klemens; Weber, Konrad P; Linnebank, Michael; Brugger, Peter

    2016-03-01

    Largely based on findings from functional neuroimaging studies, the medial parietal lobe is known to contribute to internally directed cognitive processes such as visual imagery or episodic memory. Here, we present 2 patients with behavioral impairments that extend this view. Both had chronic unilateral lesions of nearly the entire medial parietal lobe, but in opposite hemispheres. Routine neuropsychological examination conducted >4 years after the onset of brain damage showed little deficits of minor severity. In contrast, both patients reported persistent unusual visual impairment. A comprehensive series of tachistoscopic experiments with lateralized stimulus presentation and comparison with healthy participants revealed partial visual hemiagnosia for stimuli presented to their contralesional hemifield, applying inferential single-case statistics to evaluate deficits and dissociations. Double dissociations were found in 4 experiments during which participants had to integrate more than one visual element, either through comparison or formation of a global gestalt. Against the background of recent neuroimaging findings, we conclude that of all medial parietal structures, the precuneus is the most likely candidate for a crucial involvement in such bottom-up visual integration. PMID:25331599

  16. Continuous Medial Representation of Brain Structures Using the Biharmonic PDE

    PubMed Central

    Yushkevich, Paul A.

    2009-01-01

    A new approach for constructing deformable continuous medial models for anatomical structures is presented. Medial models describe geometrical objects by first specifying the skeleton of the object and then deriving the boundary surface corresponding to the skeleton. However, an arbitrary specification of a skeleton will not be “Valid” unless a certain set of sufficient conditions is satisfied. The most challenging of these is the non-linear equality constraint that must hold along the boundaries of the manifolds forming the skeleton. The main contribution of this paper is to leverage the biharmonic partial differential equation as a mapping from a codimension-0 subset of Euclidean space to the space of skeletons that satisfy the equality constraint. The PDE supports robust numerical solution on freeform triangular meshes, providing additional flexibility for shape modeling. The approach is evaluated by generating continuous medial models for a large dataset of hippocampus shapes. Generalizations to modeling more complex shapes and to representing branching skeletons are demonstrated. PMID:19059348

  17. 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

  18. The medial habenula: still neglected

    PubMed Central

    Viswanath, Humsini; Carter, Asasia Q.; Baldwin, Philip R.; Molfese, David L.; Salas, Ramiro

    2013-01-01

    The habenula is a small, bilateral brain structure located at the dorsal end of the diencephalon. This structure sends projections to the dopaminergic striatum and receives inputs from the limbic forebrain, making the habenula a unique modulator of cross-talk between these brain regions. Despite strong interest in the habenula during the seventies and eighties (Herkenham and Nauta, 1977; Beckstead, 1979; Beckstead et al., 1979; Herkenham and Nauta, 1979; Caldecott-Hazard et al., 1988), interest waned due to lack of a clearly identifiable functional role. Following Matsumoto and Hikosaka's seminal work on the lateral habenula as a predictor of negative reward in monkeys, the habenula has undergone a resurgence of scientific interest. Matsumoto and Hikosaka demonstrated an increase in habenular neuron firing when monkeys did not receive an expected juice reward (Matsumoto and Hikosaka, 2007). Studies have shown that increased habenular activity inactivates dopaminergic cells in the Rostromedial Tegmental Nucleus (RMTg) through GABAergic mechanisms (Jhou et al., 2009a,b). Additional studies link habenular activity to the regulation of serotonin and norepinephrine, suggesting the habenula modulates multiple brain systems (Strecker and Rosengren, 1989; Amat et al., 2001). These discoveries ushered in a series of new studies that have refocused attention on the lateral habenula and the importance of this small brain structure (Bianco and Wilson, 2009; Jhou et al., 2009a; Matsumoto and Hikosaka, 2009; Sartorius et al., 2010; Savitz et al., 2011). Recently, Geisler and Trimble reviewed this renewed interest in: The Lateral Habenula: No Longer Neglected (Geisler and Trimble, 2008). While the lateral habenula (LHb) has been extensively studied, the anatomically and histochemically distinct medial habenula (MHb) remains largely understudied. This short review argues that the MHb is functionally important and should be studied more aggressively. PMID:24478666

  19. The medial habenula: still neglected.

    PubMed

    Viswanath, Humsini; Carter, Asasia Q; Baldwin, Philip R; Molfese, David L; Salas, Ramiro

    2013-01-01

    The habenula is a small, bilateral brain structure located at the dorsal end of the diencephalon. This structure sends projections to the dopaminergic striatum and receives inputs from the limbic forebrain, making the habenula a unique modulator of cross-talk between these brain regions. Despite strong interest in the habenula during the seventies and eighties (Herkenham and Nauta, 1977; Beckstead, 1979; Beckstead et al., 1979; Herkenham and Nauta, 1979; Caldecott-Hazard et al., 1988), interest waned due to lack of a clearly identifiable functional role. Following Matsumoto and Hikosaka's seminal work on the lateral habenula as a predictor of negative reward in monkeys, the habenula has undergone a resurgence of scientific interest. Matsumoto and Hikosaka demonstrated an increase in habenular neuron firing when monkeys did not receive an expected juice reward (Matsumoto and Hikosaka, 2007). Studies have shown that increased habenular activity inactivates dopaminergic cells in the Rostromedial Tegmental Nucleus (RMTg) through GABAergic mechanisms (Jhou et al., 2009a,b). Additional studies link habenular activity to the regulation of serotonin and norepinephrine, suggesting the habenula modulates multiple brain systems (Strecker and Rosengren, 1989; Amat et al., 2001). These discoveries ushered in a series of new studies that have refocused attention on the lateral habenula and the importance of this small brain structure (Bianco and Wilson, 2009; Jhou et al., 2009a; Matsumoto and Hikosaka, 2009; Sartorius et al., 2010; Savitz et al., 2011). Recently, Geisler and Trimble reviewed this renewed interest in: The Lateral Habenula: No Longer Neglected (Geisler and Trimble, 2008). While the lateral habenula (LHb) has been extensively studied, the anatomically and histochemically distinct medial habenula (MHb) remains largely understudied. This short review argues that the MHb is functionally important and should be studied more aggressively. PMID:24478666

  20. Screw fixation of medial malleolar fractures: a cadaveric biomechanical study challenging the current AO philosophy.

    PubMed

    Parker, L; Garlick, N; McCarthy, I; Grechenig, S; Grechenig, W; Smitham, P

    2013-12-01

    The AO Foundation advocates the use of partially threaded lag screws in the fixation of fractures of the medial malleolus. However, their threads often bypass the radiodense physeal scar of the distal tibia, possibly failing to obtain more secure purchase and better compression of the fracture. We therefore hypothesised that the partially threaded screws commonly used to fix a medial malleolar fracture often provide suboptimal compression as a result of bypassing the physeal scar, and proposed that better compression of the fracture may be achieved with shorter partially threaded screws or fully threaded screws whose threads engage the physeal scar. We analysed compression at the fracture site in human cadaver medial malleoli treated with either 30 mm or 45 mm long partially threaded screws or 45 mm fully threaded screws. The median compression at the fracture site achieved with 30 mm partially threaded screws (0.95 kg/cm(2) (interquartile range (IQR) 0.8 to 1.2) and 45 mm fully threaded screws (1.0 kg/cm(2) (IQR 0.7 to 2.8)) was significantly higher than that achieved with 45 mm partially threaded screws (0.6 kg/cm(2) (IQR 0.2 to 0.9)) (p = 0.04 and p < 0.001, respectively). The fully threaded screws and the 30mm partially threaded screws were seen to engage the physeal scar under an image intensifier in each case. The results support the use of 30 mm partially threaded or 45 mm fully threaded screws that engage the physeal scar rather than longer partially threaded screws that do not. A 45 mm fully threaded screw may in practice offer additional benefit over 30 mm partially threaded screws in increasing the thread count in the denser paraphyseal region. PMID:24293597

  1. Medial and lateral segond fractures in a skeletally immature patient: a radiographic marker for the multiply injured knee.

    PubMed

    Kwon, Oh Soo; Park, Min Jung; Tjoumakaris, Fotios P

    2011-11-01

    Marginal fractures of the medial tibial plateau have been reported in the literature as a secondary type of Segond fracture. Some reports described this entity in the setting of combined injuries such as root avulsions of the medial meniscus, complete disruption of the posterior cruciate ligament (PCL), partial tear of the anterior cruciate ligament (ACL), and tears of the medial meniscus and medial collateral ligament. It has been postulated that medial marginal fractures are secondary to compression of the medial aspect of the femoral condyle and tibial plateau with a corresponding posterolateral corner injury. However, this mechanism of injury may not always be as straightforward.This article presents a case of an alternate injury pattern in a skeletally immature patient. A 16-year-old boy sustained a varus force and twisting injury to his knee, resulting in radiographic evidence of multiple avulsion fractures of the knee, including a fibular epiphyseal avulsion fracture and medial and lateral Segond fractures. Usually, the avulsion fractures serve as markers for significant ligamentous injuries in adult patients, but our patient had minimal injury to the PCL, ACL, and posterolateral corner. Further physical examination and imaging studies revealed an anterior horn root avulsion, meniscocapsular separation, and anterior cortical rim fracture. A combination of imaging modalities helped us further characterize the injury pattern to devise the optimal surgical plan, especially the fixation of the anterior cortical fracture of the tibia. PMID:22049962

  2. Medial thighplasty: Current concepts and practices.

    PubMed

    Bertheuil, N; Carloni, R; De Runz, A; Herlin, C; Girard, P; Watier, E; Chaput, B

    2016-02-01

    Medial thighplasty, also known as medial thigh lift, is a procedure that has been carried out for five decades. The original "Lewis" technique has undergone many changes, and thereby been rendered widely available to plastic surgeons. Given the increasingly high number of surgical reconstructions after massive weight loss, this technique is now an integral part of a surgeon's therapeutic arsenal as he strives to meet the evolving demands of patients. The objective of this article, which is based on a comprehensive review of the literature, is to summarize current knowledge on medial thighplasty and thereby allow plastic surgeons to adopt the operating technique best suited to the deformations presented by their patients and to the overall context. The different techniques, outcomes and complications are successively discussed. PMID:26433317

  3. Effects of implant stiffness, shape, and medialization depth on the acoustic outcomes of medialization laryngoplasty

    PubMed Central

    Zhang, Zhaoyan; Chhetri, Dinesh K.; Bergeron, Jennifer L.

    2014-01-01

    Objective Medialization laryngoplasty is commonly used to treat glottic insufficiency. In this study, we investigated the effects of implant stiffness (Young’s modulus), medialization depth, and implant medial surface shape on acoustic outcomes. Study Design Basic science study using ex vivo laryngeal phonation model. Methods In an ex vivo human larynx phonation model, bilateral medialization laryngoplasties were performed with implants of varying stiffness, medial surface shape (rectangular, divergent and convergent), and varying depths of medialization. The subglottal pressure, the flow rate, and the outside sound were measured as the implant parameters were varied. Results Medialization through the use of implants generally improved the harmonic-to-noise ratio (HNR) and the number of harmonics excited in the outside sound spectra. The degree of acoustic improvement depended on the implant insertion depth, stiffness, and to a lesser degree implant shape. Varying implant insertion depth led to large variations in phonation for stiff implants, but had much smaller effects for soft implants. Conclusions Implants with stiffness comparable to vocal folds provided more consistent improvement in acoustic outcomes across different implant conditions. Further investigations are required to better understand the underlying mechanisms. PMID:25499519

  4. Freestyle perforator-based propeller flap of medial arm for medial elbow reconstruction.

    PubMed

    Zang, Mengqing; Yu, Shengji; Xu, Libin; Zhao, Zhenguo; Ding, Qiang; Guo, Lingling; Liu, Yuanbo

    2015-07-01

    Elbow reconstruction is challenging for reconstructive surgeons. The purpose of this report is to present the results of the use of freestyle perforator-based propeller flap designed from the medial arm region for elbow reconstruction. The defects following soft tissue sarcoma resection at the medial and posterior elbow were repaired in two patients. The dimensions of the defects were 11 × 7 cm(2) and 10 × 7 cm(2). Two perforators were identified in each case using Doppler ultrasound probe in the medial arm, adjacent to the defect. The perforator with visible pulsation was chosen as the pedicle vessel, which was 12-cm and 7-cm proximal to the medial epicondyle. An elliptical flap, extending almost the full length of arm, was raised and rotated 180° to repair medial elbow defects. The sizes of the flaps were 17 × 8 cm(2) and 11 × 7 cm(2). The donor sites were closed directly. Both flaps survived; temporary venous congestion occurred in one case. There were no other postoperative complications. These cases illustrated that the medial arm flap might be used for reconstruction of medial elbow defects with this freestyle perforator-based propeller flap design. PMID:25417774

  5. [Arthritis of the Medial Knee Joint Compartment].

    PubMed

    Matziolis, G; Röhner, E

    2015-10-01

    23 % of all persons older than 65 years suffer from osteoarthritis of the medial compartment of the knee joint, a very common situation in orthopaedic practice 1. As a result of the demographic trend the number of patients is expected to increase in the future. Based on specific joint biomechanics and kinematics the medial knee joint compartment is more frequently affected than the lateral. Only an understanding of the functional anatomy and underlying pathology allows a critical evaluation of different available conservative and operative treatment options. This article gives an overview of diagnostic and therapeutic strategies of osteoarthritis of the medial knee joint. Frequently performed surgeries, e.g. high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) will be presented in a comparative manner. The actual scientific evidence will be given with the goal of an evidence based therapy that is adopted to stage and pathology of osteoarthritis of the medial compartment of the knee joint. PMID:26451864

  6. 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

  7. Empty Consonants in Root-Medial Position.

    ERIC Educational Resources Information Center

    Marlett, Stephen A.

    This analysis of verb morphology in Seri finds evidence that empty consonants occur in root-medial position. Analysis focuses on the parallel conjugation patterns of the verbs for "know" and "give," finding an empty consonant slot in the middle of each. This position is never preceded by a consonant, so it never appears as a geminated consonant,…

  8. 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…

  9. Femoral neck version affects medial femorotibial loading.

    PubMed

    Papaioannou, T A; Digas, Georgios; Bikos, Ch; Karamoulas, V; Magnissalis, E A

    2013-01-01

    The aim of this study was to provide a preliminary evaluation of the possible effect that femoral version may have on the bearing equilibrium conditions developed on the medial tibiofemoral compartment. A digital 3D solid model of the left physiological adult femur was used to create morphological variations of different neck-shaft angles (varus 115, normal 125, and valgus 135 degrees) and version angles (-10, 0, and +10 degrees). By means of finite element modeling and analysis techniques (FEM-FEA), a virtual experiment was executed with the femoral models aligned in a neutral upright position, distally supported on a fully congruent tibial tray and proximally loaded with a vertical only hip joint load of 2800 N. Equivalent stresses and their distribution on the medial compartment were computed and comparatively evaluated. Within our context, the neck-shaft angle proved to be of rather indifferent influence. Reduction of femoral version, however, appeared as the most influencing parameter regarding the tendency of the medial compartment to establish its bearing equilibrium towards posteromedial directions, as a consequence of the corresponding anteroposterior changes of the hip centre over the horizontal tibiofemoral plane. We found a correlation between femoral anteversion and medial tibiofemoral compartment contact pressure. Our findings will be further elucidated by more sophisticated FEM-FEA and by clinical studies that are currently planned. PMID:24959355

  10. Speed cells in the medial entorhinal cortex.

    PubMed

    Kropff, Emilio; Carmichael, James E; Moser, May-Britt; Moser, Edvard I

    2015-07-23

    Grid cells in the medial entorhinal cortex have spatial firing fields that repeat periodically in a hexagonal pattern. When animals move, activity is translated between grid cells in accordance with the animal's displacement in the environment. For this translation to occur, grid cells must have continuous access to information about instantaneous running speed. However, a powerful entorhinal speed signal has not been identified. Here we show that running speed is represented in the firing rate of a ubiquitous but functionally dedicated population of entorhinal neurons distinct from other cell populations of the local circuit, such as grid, head-direction and border cells. These 'speed cells' are characterized by a context-invariant positive, linear response to running speed, and share with grid cells a prospective bias of ∼50-80 ms. Our observations point to speed cells as a key component of the dynamic representation of self-location in the medial entorhinal cortex. PMID:26176924

  11. Stress fracture of the medial malleolus.

    PubMed

    Orava, S; Karpakka, J; Taimela, S; Hulkko, A; Permi, J; Kujala, U

    1995-03-01

    We studied eight patients who had a stress fracture of the medial malleolus. The main symptom was localized pain on the medial side of the ankle. The initial radiographs revealed the lesion for only three patients; for the other patients, the diagnosis was made with the use of isotope scans and was confirmed with computerized tomography scans, magnetic resonance images, or subsequent plain radiographs. One vertical fracture was treated initially with compression with AO screws. On the basis of our experience with stress fractures in other bones, drilling was performed to enhance the formation of bone in two patients who had delayed healing and who had had symptoms for eight and twelve months. The fractures healed four and five months after the drilling. The five patients who were managed non-operatively had to avoid running and jumping for at least three months (average, four months) so that healing could take place. All five of these fractures healed within five months. PMID:7890784

  12. [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. PMID:24169227

  13. Medial Cochlear Efferent Function: A Theoretical Analysis

    NASA Astrophysics Data System (ADS)

    Mountain, David C.

    2011-11-01

    Since the discovery of the cochlear efferent system, many hypotheses have been put forth for its function. These hypotheses for its function range from protecting the cochlea from over stimulation to improving the detection of sounds in noise. It is known that the medial efferent system innervates the outer hair cells and that stimulation of this system reduces basilar membrane and auditory nerve sensitivity which suggests that this system acts to decrease the gain of the cochlear amplifier. Here I present modeling results as well as analysis of published experimental data that suggest that the function of the medial efferent reflex is to decrease the cochlear amplifier gain by just the right amount so that the nonlinearity in the basilar membrane response lines up perfectly with the inner hair cell nonlinear transduction process to produce a hair cell receptor potential that is proportional to the logarithm of the sound pressure level.

  14. Medial epicondyle fractures in the pediatric population.

    PubMed

    Gottschalk, Hilton P; Eisner, Eric; Hosalkar, Harish S

    2012-04-01

    Humeral medial epicondyle fractures in the pediatric population account for up to 20% of elbow fractures, 60% of which are associated with elbow dislocation. Isolated injuries can occur from either direct trauma or avulsion. Medial epicondyle fractures also occur in combination with elbow dislocations. Traditional management by cast immobilization increasingly is being replaced with early fixation and mobilization. Relative indications for surgical fixation include ulnar nerve entrapment, gross elbow instability, and fractures in athletic or other patients who require high-demand upper extremity function. Absolute indications for surgical intervention are an incarcerated fragment in the joint or open fractures. Radiographic assessment of these injuries and their true degree of displacement remain controversial. PMID:22474092

  15. Mechanoreceptors in the human medial meniscus.

    PubMed

    Zimny, M L; Albright, D J; Dabezies, E

    1988-01-01

    Medial menisci, obtained at autopsy, were sectioned into radial segments which were stained in bulk using a modified gold chloride method following pretreatment with Triton X-100. Segments were then sectioned on a sliding microtome at 100 microns, mounted on slides, dehydrated and coverslipped. Axons were seen penetrating from the perimeniscal tissue into the outer third of the meniscus with a heavier concentration at the horns. Neural elements were identified in the perimeniscal tissue and in the outer and middle thirds of the meniscus, but not in the inner third. The medial meniscus is capable of afferent input to the central nervous system of importance to the biomechanical function of the joint. PMID:3213403

  16. Usefulness of the Medial Portal during Hip Arthroscopy

    PubMed Central

    Kang, Chan; Hwang, Jung-Mo; Park, Eugene J.

    2015-01-01

    The current conventional portals for hip arthroscopic surgery are the anterior, anterolateral, and posterolateral portals. For lesions in the medial anteroinferior or posteroinferior portion of the hip, these portals provide insufficient access to the lesion and consequently lead to incomplete treatment. Thus, in such a situation, a medial portal approach might be helpful. However, operators have avoided this procedure because of the risk of injury to the obturator, femoral neurovascular structures, and the medial femoral circumflex artery. Thus, to overcome the disadvantages of the conventional method for medial lesions of the hip, we performed a cadaveric study to evaluate the technique, usefulness, and risk of the medial portal technique. PMID:26330964

  17. Surgical treatment of symptomatic discoid medial meniscus in childhood: a case report.

    PubMed

    Kalenderer, Onder; Türken, Mehmet Aykut; Agus, Haluk

    2012-07-01

    If the meniscus has a spherical shape and not a semilunary structure, it is called as discoid meniscus. This anomaly is generally seen in the lateral meniscus; however, it is rare in the medial meniscus. Although the discoid meniscus is usually asymptomatic in children and adolescents, it could present as a meniscal tear. An 11-year-old boy was admitted to our hospital with right knee pain and lack of extension of the knee joint. He was diagnosed as discoid medial meniscus. On physical examination, we observed tenderness at the knee joint line with an effusion of the knee and a restriction during the extension movement of the knee joint. McMurray test was positive. Conventional radiograms revealed widening of the medial joint line and cupping of the medial tibial plateau. Magnetic resonance imaging indicated a discoid meniscus image at sagittal slices. In this case, after the arthroscopic partial menisectomy, we obtained an excellent result at 2 years follow-up. PMID:21685803

  18. β2-Adrenergic agonist-induced hypertrophy of the quadriceps skeletal muscle does not modulate disease severity in the rodent meniscectomy model of osteoarthritis

    PubMed Central

    Tonge, D.P.; Jones, S.W.; Parr, T.; Bardsley, R.; Doherty, M.; Maciewicz, R.A.

    2010-01-01

    Summary Objective To examine whether β2-adrenergic agonist-induced hypertrophy of the quadriceps skeletal muscle can modulate the severity of osteoarthritis (OA) in the rodent meniscectomy (MNX) model. Methods Male Lewis rats were subcutaneously administered with 1.5 mg/kg/day clenbuterol hydrochloride (n = 15) or saline vehicle (n = 20) for 14 days. Following pre-treatment, five animals from each group were sacrificed to assess the immediate effects of clenbuterol. The remaining animals underwent either invasive knee surgery (clenbuterol pre-treated n = 10; saline pre-treated n = 10) or a sham control surgical procedure (saline pre-treated n = 5). During disease initiation and progression, weight bearing was assessed by hindlimb loading. Myosin heavy chain (MHC) protein isoforms were quantified by silver stained SDS PAGE. OA severity was graded by assessment of toluidine blue stained step coronal sections of the total knee joint. Results Clenbuterol treatment resulted in an increase in total bodyweight, growth rate and in quadriceps skeletal muscle mass. Meniscal surgery resulted in the development of OA-like lesions, changes to weight bearing, and changes in MHC protein expression in the quadriceps. Clenbuterol-induced skeletal muscle hypertrophy had no effect on either weight bearing or articular pathology following MNX surgery. Conclusions Our data reveal that clenbuterol-induced skeletal muscle hypertrophy is unable to mimic the beneficial clinical effects of increased musculature derived through targeted strength training in humans, in a rodent model of MNX-induced OA. In addition we observed fibre-type switching to “slow twitch” in the quadriceps muscle during the induction of OA that warrants further investigation as to its relationship to joint stability. PMID:20060953

  19. Application of Additional Medial Plate in Treatment of Proximal Humeral Fractures With Unstable Medial Column

    PubMed Central

    He, Yu; He, Jiliang; Wang, Fu; Zhou, Dongsheng; Wang, Yan; Wang, Bomin; Xu, Shihong

    2015-01-01

    Abstract The purpose of this study was to use finite element analysis to compare the biomechanical characteristics after lateral locking plate (LLP) or LLP with a medial anatomical locking plate (LLP-MLP) fixation of proximal humeral fractures with an unstable medial column. First, a 3-dimensional, finite element analysis model was developed. Next, LLP and LLP-MLP implants were instrumented into the proximal humeral fracture models. Compressive and rotational loads were then applied to the humerus model to determine the biomechanical characteristics. Both normal and osteoporotic proximal humerus fractures were simulated using 2 internal fixation methods each under 7 loading conditions. To assess the biomechanical characteristics, the construct stiffness, fracture micromotion, and stress distribution on the implants were recorded and compared. The LLP-MLP method provided both lateral and medial support that reduced the stress on the LLP and the amount of displacement in the fracture region. In contrast, the LLP method resulted in more instability in the medial column and larger magnitudes of stress. In osteoporotic bone, the LLP was more inclined to fail than LLP-MLP. The LLP-MLP method provides a strong support for the medial column and increases the stability of the region surrounding the fracture. PMID:26469918

  20. Arthroscopic partial resection of the discoid meniscus in children.

    PubMed

    Atay, O A; Doral, M N; Aksoy, M C; Tetik, O; Leblebicioğlu, G

    1997-01-01

    Thirteen children with 14 lateral discoid menisci were reviewed at an average follow-up of 2.7 years. Their average age at the time of the operation was 12.8 years. Most of the children had vague and intermittent painful symptoms, and the classical "clunk" was demonstrable in nine of the 13 patients in clinical examinations. Thirteen children underwent arthroscopic partial meniscectomy for symptomatic discoid lateral meniscus, by performing partial resection. This procedure, modifying the discoid lateral meniscus to the normal semilunar shape, was indicated only when the capsular attachment was intact. The results were excellent both clinically and radiologically. Furthermore, rehabilitation time was considerably shorter than the time required after open procedures. Arthroscopic discoid meniscus surgery performed by experienced and skilled hands gives better results. According to the literature and our experiences, it is better to perform open techniques in patients with stiff knees. Additionally, it is technically feasible to use small joint instruments in the pediatric age group. PMID:9433153

  1. Microvascular medial femoral condylar flaps in 107 consecutive reconstructions in the head and neck.

    PubMed

    Brandtner, Christian; Hachleitner, Johannes; Bottini, Gian Battista; Buerger, Heinz; Gaggl, Alexander

    2016-07-01

    We have assessed the role of the medial femoral condylar flap in 107 patients who had reconstructions of the head and neck. We retrospectively reviewed their medical records for indications, complications, and outcomes. The flap was primarily used for coverage of alveolar ridge defects (n=67), secondly for defects of the facial bone, calvaria, or skull base (n=35), and thirdly for partial laryngeal defects (n=5). Two flaps were lost. One patient fractured a femur 5 weeks postoperatively. The duration of follow up ranged from 6 months to 12 years. The medial femoral condylar flap is well-suited to individual reconstructions of the alveolar ridge, midface, calvaria, skull base, and part of the larynx with poor recipient sites. The flap does not replace other wellknown flaps, but offers new solutions for solving special problems in head and neck surgery. PMID:27020752

  2. Bilateral bucket handle medial meniscal tears of the knee: A case report☆

    PubMed Central

    Sezer, Hasan Basri; Arikan, Yavuz; Armagan, Raffi; Eren, Osman Tugrul

    2013-01-01

    INTRODUCTION Meniscal tears may cause knee pain and functional impairment. Bilateral bucket-handle meniscal tears is an uncommon condition. PRESENTATION OF CASE This report presents the case of a 35-year-old male patient with bilateral bucket handle medial meniscal tears that occurred nonsimultaneously. The lesions were treated arthroscopically with partial resection in one knee and meniscal suture in the other. DISCUSSION Bucket handle meniscal tear of meniscus without underlying meniscal, ligamentous pathology or lower limb deformity is a rare condition. CONCLUSION To our knowledge, bilateral bucket handle medial meniscal tears without underlying meniscal anomalies have been reported in only two cases before, and our case is the third one. PMID:24012575

  3. Consensus Statement on Indications and Contraindications for Medial Unicompartmental Knee Arthroplasty.

    PubMed

    Berend, Keith R; Berend, Michael E; Dalury, David F; Argenson, Jean-Noel; Dodd, Chris A; Scott, Richard D

    2015-01-01

    Previous work, now nearly 30 years dated, is frequently cited as the "gold standard" for the indications and contraindications for medial unicompartmental knee arthroplasty (UKA). The purpose of this article is to review current literature on the indications and contraindications to UKA and develop a consensus statement based on those data. Six surgeons with a combined experience of performing more than 8,000 partial knee arthroplasties were surveyed. Surgeons then participated in a discussion, emerging proposal, collaborative modification, and final consensus phase. The final consensus on primary indications and contraindications is presented. Notably, the authors provide consensus on previous contraindications, which are no longer considered to be contraindications. The authors provide an updated and concise review of the current indications and contraindications for medial UKA using scientifically based consensus-building methodology. PMID:26731390

  4. Medial patellofemoral ligament reconstruction in patellar instability

    PubMed Central

    Krishna Kumar, MS; Renganathan, Sankarram; Joseph, Clement J; Easwar, TR; Rajan, David V

    2014-01-01

    Background: Medial patellofemoral ligament (MPFL) is one of the major static medial stabilising structures of the patella. MPFL is most often damaged in patients with patellar instability. Reconstruction of MPFL is becoming a common surgical procedure in treating patellar instability. We hypothesised that MPFL reconstruction was adequate to treat patients with patellar instability if the tibial tubercle and the centre of the trochlear groove (TT-TG) value was less than 20 mm and without a dysplastic trochlea. Materials and Methods: 30 patients matching our inclusion criteria and operated between April 2009 and May 2011 were included in the study. MPFL reconstruction was performed using gracilis tendon fixed with endobutton on the patellar side and bio absorbable interference screw or staple on the femoral side. Patients were followed up with subjective criteria, Kujala score and Lysholm score. Results: The mean duration of followup was 25 months (range 14-38 months). The mean preoperative Kujala score was 47.5 and Lysholm score was 44.7. The mean postoperative Kujala score was 87 and Lysholm score was 88.06. None of the patients had redislocation. Conclusion: MPFL reconstruction using gracilis tendon gives excellent results in patients with patellar instability with no redislocations. Some patients may have persistence of apprehension. PMID:25298558

  5. Epilepsy (partial)

    PubMed Central

    2011-01-01

    Introduction About 3% of people will be diagnosed with epilepsy during their lifetime, but about 70% of people with epilepsy eventually go into remission. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of starting antiepileptic drug treatment following a single seizure? What are the effects of drug monotherapy in people with partial epilepsy? What are the effects of additional drug treatments in people with drug-resistant partial epilepsy? What is the risk of relapse in people in remission when withdrawing antiepileptic drugs? What are the effects of behavioural and psychological treatments for people with epilepsy? What are the effects of surgery in people with drug-resistant temporal lobe epilepsy? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 83 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiepileptic drugs after a single seizure; monotherapy for partial epilepsy using carbamazepine, gabapentin, lamotrigine, levetiracetam, phenobarbital, phenytoin, sodium valproate, or topiramate; addition of second-line drugs for drug-resistant partial epilepsy (allopurinol, eslicarbazepine, gabapentin, lacosamide, lamotrigine, levetiracetam, losigamone, oxcarbazepine, retigabine, tiagabine, topiramate, vigabatrin, or zonisamide); antiepileptic drug withdrawal for people with partial or

  6. Combined Reconstruction of the Medial Patellofemoral Ligament With Quadricipital Tendon and the Medial Patellotibial Ligament With Patellar Tendon

    PubMed Central

    Hinckel, Betina Bremer; Gobbi, Riccardo Gomes; Demange, Marco Kawamura; Bonadio, Marcelo Batista; Pécora, José Ricardo; Camanho, Gilberto Luis

    2016-01-01

    Although the medial patellotibial ligament (MPTL) has been neglected regarding its function in patellar stability, recently, its importance in terminal extension and during flexion has been recognized. Indications for reconstruction of the medial patellofemoral ligament combined with the MPTL are extension subluxation, flexion instability, children with anatomic risk factors for patellar instability, and knee hyperextension associated with generalized laxity. We describe a combined reconstruction of the medial patellofemoral ligament with quadricipital tendon and reconstruction of the MPTL with patellar tendon autografts. PMID:27073782

  7. DIFFERENT DISTRIBUTIONS OF CALBINDIN AND CALRETININ IMMUNOSTAINING ACROSS THE MEDIAL AND DORSAL DIVISIONS OF THE MOUSE MEDIAL GENICULATE BODY

    PubMed Central

    LU, E.; LLANO, D.A.; SHERMAN, S. M.

    2009-01-01

    We studied the distributions of calretinin and calbindin immunoreactivity in subdivisions of the mouse medial geniculate body and the adjacent paralaminar nuclei. We found that the vast majority of labeled cells in the dorsal division of the medial geniculate body were immunoreactive for calbindin only, whereas most of the remaining labeled cells were double-labeled. Very few calretinin+ only cells were observed. By contrast, we observed significant proportions of calbindin+ only, calretinin+ only and double-labeled cells in the medial division of the medial geniculate body. Further, the distributions of calbindin-only, calretinin-only and double-labeled cells did not differ between the medial division of the medial geniculate body, the suprageniculate nucleus, the peripeduncular nucleus and the posterior intralaminar nucleus. We found essentially no somatic staining for either calbindin or calretinin in the ventral division of the medial geniculate body. These data suggest that there are distinct neurochemical differences between the two nonlemniscal auditory thalamic nuclei. In addition, these data extend previous observations that the medial division of the medial geniculate body shares many properties with the paralaminar group of nuclei. PMID:19643174

  8. 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

  9. Medial Patellofemoral Ligament Reconstruction: A Comprehensive Review

    PubMed Central

    Kim, Hee-June

    2015-01-01

    It has been suggested that in the majority of patellar dislocation cases, the medial patellofemoral ligament (MPFL) is disrupted with a high recurrence rate especially in female patients. Although MPFL tear is not the primary cause of instability, MPFL reconstruction is effective for stabilizing the knee and may alone prevent lateral patellar dislocation. There is limited but growing evidence that MPFL reconstruction for patellofemoral instability leads to excellent functional outcomes. Growing awareness of the biomechanical contribution of the MPFL has led to an upsurge in the publication of techniques and trials dealing with reconstructive techniques, warranting a review that includes the most recent evidence. The aim of this article was to review and summarize the recent literatures concerning MPFL reconstruction and provide a comprehensive review of previous studies ranging from basic science to current surgical techniques and results. PMID:26389065

  10. Medial septum regulates the hippocampal spatial representation

    PubMed Central

    Mamad, Omar; McNamara, Harold M.; Reilly, Richard B.; Tsanov, Marian

    2015-01-01

    The hippocampal circuitry undergoes attentional modulation by the cholinergic medial septum. However, it is unclear how septal activation regulates the spatial properties of hippocampal neurons. We investigated here what is the functional effect of selective-cholinergic and non-selective septal stimulation on septo-hippocampal system. We show for the first time selective activation of cholinergic cells and their differential network effect in medial septum of freely-behaving transgenic rats. Our data show that depolarization of cholinergic septal neurons evokes frequency-dependent response from the non-cholinergic septal neurons and hippocampal interneurons. Our findings provide vital evidence that cholinergic effect on septo-hippocampal axis is behavior-dependent. During the active behavioral state the activation of septal cholinergic projections is insufficient to evoke significant change in the spiking of the hippocampal neurons. The efficiency of septo-hippocampal processing during active exploration relates to the firing patterns of the non-cholinergic theta-bursting cells. Non-selective septal theta-burst stimulation resets the spiking of hippocampal theta cells, increases theta synchronization, entrains the spiking of hippocampal place cells, and tunes the spatial properties in a timing-dependent manner. The spatial properties are augmented only when the stimulation is applied in the periphery of the place field or 400–650 ms before the animals approached the center of the field. In summary, our data show that selective cholinergic activation triggers a robust network effect in the septo-hippocampal system during inactive behavioral state, whereas the non-cholinergic septal activation regulates hippocampal functional properties during explorative behavior. Together, our findings uncover fast septal modulation on hippocampal network and reveal how septal inputs up-regulate and down-regulate the encoding of spatial representation. PMID:26175674

  11. A simple, safe and reliable surgical landmark for medial epicondylectomy

    PubMed Central

    McCann, Philip S; Clark, Damian; Amirfeyz, Rouin

    2014-01-01

    Background Various surgical strategies have been described for the treatment of cubital tunnel syndrome, including medial epicondylectomy. This aims to decompress the ulnar nerve and allow a ‘mini anterior transposition’. The major concern over medial epicondylectomy is the potential for postoperative iatrogenic valgus instability. Methods We utilized a surgical landmark for medial epicondylectomy based on the medial aspect of the ulnar nerve with the elbow in 90° of flexion in 12 cadaveric upper limbs. The size of the resultant fragment was measured and, subsequently, the medial collateral ligament was dissected and the elbow stressed to assess its integrity. Results This technique resulted in the excision of a fragment of mean width 8 mm (range 6 mm to 11 mm) and allowed the ulnar nerve to smoothly translate anteriorly in flexion. The anterior band of the ulnar collateral ligament was macroscopically preserved in all cases and there was no valgus instability. Conclusions The medial border of the ulnar nerve is a simple, safe and reliable surgical landmark for medial epicondylectomy. This technique offers advantages over other described methods of assessing the location at which to perform a medial epicondylectomy.

  12. Snail mediates medial-lateral patterning of the ascidian neural plate.

    PubMed

    Hudson, Clare; Sirour, Cathy; Yasuo, Hitoyoshi

    2015-07-15

    The ascidian neural plate exhibits a regular, grid-like arrangement of cells. Patterning of the neural plate across the medial-lateral axis is initiated by bilateral sources of Nodal signalling, such that Nodal signalling induces expression of lateral neural plate genes and represses expression of medial neural plate genes. One of the earliest lateral neural plate genes induced by Nodal signals encodes the transcription factor Snail. Here, we show that Snail is a critical downstream factor mediating this Nodal-dependent patterning. Using gain and loss of function approaches, we show that Snail is required to repress medial neural plate gene expression at neural plate stages and to maintain the lateral neural tube genetic programme at later stages. A comparison of these results to those obtained following Nodal gain and loss of function indicates that Snail mediates a subset of Nodal functions. Consistently, overexpression of Snail can partially rescue a Nodal inhibition phenotype. We conclude that Snail is an early component of the gene regulatory network, initiated by Nodal signals, that patterns the ascidian neural plate. PMID:25962578

  13. Consequences of temporary inhibition of the medial amygdala on social recognition memory performance in mice.

    PubMed

    Noack, Julia; Murau, Rita; Engelmann, Mario

    2015-01-01

    Different lines of investigation suggest that the medial amygdala is causally involved in the processing of information linked to social behavior in rodents. Here we investigated the consequences of temporary inhibition of the medial amygdala by bilateral injections of lidocaine on long-term social recognition memory as tested in the social discrimination task. Lidocaine or control NaCl solution was infused immediately before learning or before retrieval. Our data show that lidocaine infusion immediately before learning did not affect long-term memory retrieval. However, intra-amygdalar lidocaine infusions immediately before choice interfered with correct memory retrieval. Analysis of the aggressive behavior measured simultaneously during all sessions in the social recognition memory task support the impression that the lidocaine dosage used here was effective as it-at least partially-reduced the aggressive behavior shown by the experimental subjects toward the juveniles. Surprisingly, also infusions of NaCl solution blocked recognition memory at both injection time points. The results are interpreted in the context of the importance of the medial amygdala for the processing of non-volatile odors as a major contributor to the olfactory signature for social recognition memory. PMID:25972782

  14. Angiotensin II Induces Region-Specific Medial Disruption during Evolution of Ascending Aortic Aneurysms

    PubMed Central

    Rateri, Debra L.; Davis, Frank M.; Balakrishnan, Anju; Howatt, Deborah A.; Moorleghen, Jessica J.; O’Connor, William N.; Charnigo, Richard; Cassis, Lisa A.; Daugherty, Alan

    2015-01-01

    Angiotensin II (Ang II) promotes development of ascending aortic aneurysms (AAs), but progression of this pathology is undefined. We evaluated factors potentially involved in progression, and determined the temporal sequence of tissue changes during development of Ang II–induced ascending AAs. Ang II infusion into C57BL/6J mice promoted rapid expansion of the ascending aorta, with significant increases within 5 days, as determined by both in vivo ultrasonography and ex vivo sequential acquisition of tissues. Rates of expansion were not significantly different in LDL receptor–null mice fed a saturated fat-enriched diet, demonstrating a lack of effect of hypercholesterolemia. Augmenting systolic blood pressure with norepinephrine infusion had no significant effect on ascending aortic expansion. Pathological changes observed within 5 days of Ang II infusion included increased medial thickness and intramural hemorrhage characterized by erythrocyte extravasation in outer lamellar layers of the media. Intramedial hemorrhage was not observed after prolonged Ang II infusion, although partial medial disruption was present. Elastin fragmentation and transmural medial breaks of the ascending aorta were observed with continued Ang II infusion, which were restricted to anterior aspects. CD45+ cells accumulated in adventitia but were minimal in media. Similar pathology was observed in tissues obtained from patients with ascending AAs. In conclusion, Ang II promotes ascending AAs through region-specific changes that are independent of hypercholesterolemia or systolic blood pressure. PMID:25038458

  15. Angiotensin II induces region-specific medial disruption during evolution of ascending aortic aneurysms.

    PubMed

    Rateri, Debra L; Davis, Frank M; Balakrishnan, Anju; Howatt, Deborah A; Moorleghen, Jessica J; O'Connor, William N; Charnigo, Richard; Cassis, Lisa A; Daugherty, Alan

    2014-09-01

    Angiotensin II (Ang II) promotes development of ascending aortic aneurysms (AAs), but progression of this pathology is undefined. We evaluated factors potentially involved in progression, and determined the temporal sequence of tissue changes during development of Ang II-induced ascending AAs. Ang II infusion into C57BL/6J mice promoted rapid expansion of the ascending aorta, with significant increases within 5 days, as determined by both in vivo ultrasonography and ex vivo sequential acquisition of tissues. Rates of expansion were not significantly different in LDL receptor-null mice fed a saturated fat-enriched diet, demonstrating a lack of effect of hypercholesterolemia. Augmenting systolic blood pressure with norepinephrine infusion had no significant effect on ascending aortic expansion. Pathological changes observed within 5 days of Ang II infusion included increased medial thickness and intramural hemorrhage characterized by erythrocyte extravasation in outer lamellar layers of the media. Intramedial hemorrhage was not observed after prolonged Ang II infusion, although partial medial disruption was present. Elastin fragmentation and transmural medial breaks of the ascending aorta were observed with continued Ang II infusion, which were restricted to anterior aspects. CD45(+) cells accumulated in adventitia but were minimal in media. Similar pathology was observed in tissues obtained from patients with ascending AAs. In conclusion, Ang II promotes ascending AAs through region-specific changes that are independent of hypercholesterolemia or systolic blood pressure. PMID:25038458

  16. Medial and Lateral Canthal Reconstruction with an Orbicularis Oculi Myocutaneous Island Flap

    PubMed Central

    Han, Jihyeon; Kwon, Sung Tack; Kim, Suk Wha

    2015-01-01

    Background The eyelid and canthal areas are common locations for cutaneous tumors. The medial canthus includes, among many other apparatuses, the canthal tendon and lacrimal canaliculi, and its characteristic thin and supple skin is hard to mimic and restore using tissue from other regions. Accordingly, reconstruction of the canthal area can prove challenging for surgeons. Although various methods, such as skin grafts and local flaps from adjacent regions, have been utilized for reconstructive purposes, they present known disadvantages. However, we were able to successfully reconstruct both lateral and medial canthal area defects by using orbicularis oculi myocutaneous island flaps. Methods Our study included seven patients who underwent medial or lateral canthal region reconstruction, using orbicularis oculi myocutaneous island flaps, between 2011 and 2014, following either cutaneous tumor excision or traumatic avulsion injury. Results Five patients had basal cell carcinoma, one had squamous cell carcinoma of the eyelid, and one had sustained a traumatic avulsion injury of the eyelid and canthal area. Entire flap loss was not observed in any patient, but one-a heavy smoker-showed partial flap loss, which healed with secondary intention and yielded acceptable results. Donor site morbidity was not observed, and all patients were satisfied with their surgical outcomes. Conclusions The canthal regions can be successfully reconstructed with orbicularis oculi myocutaneous island flaps. These flaps offer several key advantages, including similarity in texture, color, and thickness to the recipient site and a negligible incidence of donor site morbidity. PMID:25606488

  17. Precaruncular approach for the reconstruction of medial orbital wall fractures.

    PubMed

    You, Hi-Jin; Kim, Deok-Woo; Dhong, Eun-Sang; Yoon, Eul-Sik

    2014-01-01

    To reconstruct medial orbital wall fractures with a clear, least dissection, an alternative method, precaruncular approach, has been performed. We reviewed 36 patients with medial blowout fractures treated with this technique. The incision was made between the caruncle and medial canthal skin at the mucocutaneous junction, and was continued along the conjunctival fornix superiorly and inferiorly. An extended conjunctival incision was carried for additional access to the orbit floor. The dissection continued medially and proceeded along the preseptal plane. The clinical results were assessed by postoperative computed tomographic scan and by reviewing postoperative complications. Postoperatively, computed tomographic scans demonstrated adequate reduction of soft tissues and correct positioning of the inserted implant without surgical complications. In most cases, the edema resolved within 24 to 48 hours after surgery. The precaruncular approach is a good option in reconstructing medial orbital wall fractures because it provides satisfactory exposure with superior cosmetic result. PMID:23241800

  18. A dysexecutive syndrome of the medial thalamus.

    PubMed

    Liebermann, Daniela; Ploner, Christoph J; Kraft, Antje; Kopp, Ute A; Ostendorf, Florian

    2013-01-01

    Thalamic stroke is associated with neurological and cognitive sequelae. Resulting neuropsychological deficits vary with the vascular territory involved. Whereas sensory, motor and memory deficits following thalamic stroke are comparatively well characterized, the exact relationship between executive dysfunction and thalamic damage remains more ambiguous. To assess the pattern of executive-cognitive deficits following thalamic stroke and its possible association with distinct thalamic nuclei, 19 patients with focal thalamic lesions were examined with high-resolution structural imaging and neuropsychological testing. Twenty healthy individuals served as controls. Patient MRIs were co-registered to an atlas of the human thalamus. Lesion overlap and subtraction analyses were used for lesion-to-symptom mapping. In eight patients (42.1%), neuropsychological assessment demonstrated a disproportionate deficit in the Wisconsin Card Sorting Test (WCST), while other executive and memory functions were much less affected. Subtraction analysis revealed an area in the left medial thalamus, mainly consisting of the centromedian and parafascicular nuclei (CM-Pf complex) that was damaged in these patients and spared in patients with normal WCST performance. Thus, damage to the CM-Pf complex may yield a distinct dysexecutive syndrome in which deficient maintenance and shifting between cognitive sets predominates. We hypothesize that the CM-Pf complex may contribute to maintenance and shifting of cognitive sets by virtue of its dense connections with the striatum. The pattern of executive dysfunction following thalamic stroke may vary considerably with lesion location. PMID:22172979

  19. Optogenetic dissection of medial prefrontal cortex circuitry

    PubMed Central

    Riga, Danai; Matos, Mariana R.; Glas, Annet; Smit, August B.; Spijker, Sabine; Van den Oever, Michel C.

    2014-01-01

    The medial prefrontal cortex (mPFC) is critically involved in numerous cognitive functions, including attention, inhibitory control, habit formation, working memory and long-term memory. Moreover, through its dense interconnectivity with subcortical regions (e.g., thalamus, striatum, amygdala and hippocampus), the mPFC is thought to exert top-down executive control over the processing of aversive and appetitive stimuli. Because the mPFC has been implicated in the processing of a wide range of cognitive and emotional stimuli, it is thought to function as a central hub in the brain circuitry mediating symptoms of psychiatric disorders. New optogenetics technology enables anatomical and functional dissection of mPFC circuitry with unprecedented spatial and temporal resolution. This provides important novel insights in the contribution of specific neuronal subpopulations and their connectivity to mPFC function in health and disease states. In this review, we present the current knowledge obtained with optogenetic methods concerning mPFC function and dysfunction and integrate this with findings from traditional intervention approaches used to investigate the mPFC circuitry in animal models of cognitive processing and psychiatric disorders. PMID:25538574

  20. Subspecialization in the human posterior medial cortex

    PubMed Central

    Bzdok, Danilo; Heeger, Adrian; Langner, Robert; Laird, Angela R.; Fox, Peter T.; Palomero-Gallagher, Nicola; Vogt, Brent A.; Zilles, Karl; Eickhoff, Simon B.

    2014-01-01

    The posterior medial cortex (PMC) is particularly poorly understood. Its neural activity changes have been related to highly disparate mental processes. We therefore investigated PMC properties with a data-driven exploratory approach. First, we subdivided the PMC by whole-brain coactivation profiles. Second, functional connectivity of the ensuing PMC regions was compared by task-constrained meta-analytic coactivation mapping (MACM) and task-unconstrained resting-state correlations (RSFC). Third, PMC regions were functionally described by forward/reverse functional inference. A precuneal cluster was mostly connected to the intraparietal sulcus, frontal eye fields, and right temporo-parietal junction; associated with attention and motor tasks. A ventral posterior cingulate cortex (PCC) cluster was mostly connected to the ventromedial prefrontal cortex and middle left inferior parietal cortex (IPC); associated with facial appraisal and language tasks. A dorsal PCC cluster was mostly connected to the dorsomedial prefrontal cortex, anterior/posterior IPC, posterior midcingulate cortex, and left dorsolateral prefrontal cortex; associated with delay discounting. A cluster in the retrosplenial cortex was mostly connected to the anterior thalamus and hippocampus. Furthermore, all PMC clusters were congruently coupled with the default mode network according to task-constrained but not task-unconstrained connectivity. We thus identified distinct regions in the PMC and characterized their neural networks and functional implications. PMID:25462801

  1. Congenital absence of the medial meniscus associated with lipoma arborescens.

    PubMed

    Utkan, Ali; Ozkan, Güray; Köse, Cem Cüneyt; Ciliz, Deniz Sözmen; Albayrak, Ahmet Levent

    2010-06-01

    Congenital abnormalities of the medial meniscus are extremely rare and have been reported commonly with other deformities. We report an isolated aplasia of the medial meniscus. A 37-year-old man presented with a slow-growing painless swelling, accompanied by intermittent effusion of his left knee. Magnetic resonance imaging demonstrated frond-like proliferations of fatty synovium. He was initially diagnosed with synovial chondromatosis, but later found to have lipoma arborescens. While an arthroscopic synovectomy was being performed, congenital absence of the medial meniscus was discovered as an incidental finding. PMID:19766501

  2. Identifying intrasulcal medial surfaces for anatomically consistent reconstruction of the cerebral cortex

    NASA Astrophysics Data System (ADS)

    Osechinskiy, Sergey; Kruggel, Frithjof

    2011-03-01

    A novel approach to identifying poorly resolved boundaries between adjacent sulcal cortical banks in MR images of the human brain is presented. The algorithm calculates an electrostatic potential field in a partial differential equation (PDE) model of an inhomogeneous dielectric layer of gray matter that surrounds conductive white matter. Correspondence trajectories and geodesic distances are computed along the streamlines of the potential field gradient using PDEs in a Eulerian framework. The skeleton of a sulcal medial boundary is identified by a simple procedure that finds irregularities/collisions in the field of correspondences. The skeleton detection procedure is robust to noise, does not produce spurious artifacts and does not require tunable parameters. Results of the algorithm are compared with a closely related technique, called Anatomically Consistent Enhancement (ACE) (Han et al. CRUISE: Cortical reconstruction using implicit surface evolution, 2004). Results demonstrate that the approach proposed here has a number of advantages over ACE and produces skeletons with a more regular structure. This algorithm was developed as a part of a more general PDE-based framework for cortical reconstruction, which integrates the potential field gradient flow and the skeleton barriers into a level set deformable model. This technique is primarily aimed at anatomically consistent and accurate reconstruction of cortical surface models in the presence of imaging noise and partial volume effects, but the identified intrasulcal medial surfaces can serve other purposes as well, e.g. as landmarks in nonrigid registration, or as sulcal ribbons that characterize the cortical folding.

  3. Medial portion of the cavernous sinus: quantitative analysis of the medial wall.

    PubMed

    Yilmazlar, Selcuk; Kocaeli, Hasan; Aydiner, Fatma; Korfali, Ender

    2005-09-01

    Pituitary tumors invade the cavernous sinus via the medial wall. Researchers have speculated that this wall is composed of dura and that substances secreted by tumors might damage this barrier. In contrast to the lateral wall, little is known about the structure of the medial wall of the cavernous sinus (MWCS). This study provides the first detailed quantitative (thickness) and qualitative (histological) assessment of the MWCS. Eighteen sellar-parasellar tissue blocks were obtained from adult human autopsies. Ten specimens were used for microsurgical dissection and macroscopic anatomical description. Eight specimens were used for histopathological study and for recording computer measurements of MWCS thickness. Each of these eight specimens was divided into three approximately equal-sized pieces, with cuts made in the coronal plane from posterior to anterior starting at the anterior level of the pituitary stalk. Wall thicknesses were compared in the three different regions (posterior, middle, anterior), and also on the left vs. the right sides. The investigations showed that the MWCS is a distinct dural layer that forms a barrier between the medial venous space of the cavernous sinus and the pituitary gland. The mean thickness of the 48 total (left and right) MWCS observed in the 24 sections examined was 0.195 +/- 0.066 mm (range = 0.080-0.387 mm). This wall is composed of loosely arranged collagen fibers that comprise a specific layer known as "meningeal dura." The posterior third of the MWCS was significantly thinner than the middle third (P = 0.0014) or anterior third (P = 0.0001). No macro- or microscopic defects were observed in any of the MWCS in the 18 specimens. The thinness of the posterior MWCS suggests that this is the most likely path for extension of pituitary tumors into the cavernous sinus. PMID:16015624

  4. CT evaluation of medial clavicular epiphysis as a method of bone age determination in adolescents and young adults

    PubMed Central

    Ufuk, Furkan; Agladioglu, Kadir; Karabulut, Nevzat

    2016-01-01

    PURPOSE We aimed to investigate the use of computed tomography (CT) staging of the medial clavicular epiphysis ossification in forensic bone age determination, and find a CT criterion to determine whether an individual is adult or not. METHODS Chest CT and pulmonary CT angiography exams of 354 patients between 10 and 30 years of age (mean, 21.4 years) were retrospectively evaluated for epiphyseal ossification phase of the bilateral medial clavicles (708 clavicles) and compared with the sex and chronologic age of the individuals. The ossification phase of the medial clavicular epiphyses was classified from stage I to stage V using a modified staging system. RESULTS Epiphyseal ossification center appeared from 11 to 21 years of age. Partial fusion occurred between 16 and 23 years of age. Complete fusion was first achieved at the ages of 18 and 19 years for male and female individuals, respectively. The probability of an individual being ≥18 years old was 70.8% in stage III A and 100% in stages III B, IV, and V in females and males. CONCLUSION CT evaluation of the medial clavicular epiphysis is helpful in forensic age determination and stage III B can be used as a criterion to make the prediction that an individual is older than 18 years. PMID:27015321

  5. Photocopy of photograph in Fitzsimons Army Medial Center Real Property ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photocopy of photograph in Fitzsimons Army Medial Center Real Property Book (green cloth cover), south and west sides. - Fitzsimons General Hospital, Officers Quarters, Northeast Corner of West Harlow Avenue & North Seventh Street, Aurora, Adams County, CO

  6. 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. PMID:16810354

  7. Medial Patellofemoral Ligament Reconstruction for Patellar Dislocation

    PubMed Central

    Mackay, Nicola D.; Smith, Nicholas A.; Parsons, Nick; Spalding, Tim; Thompson, Peter; Sprowson, Andrew P.

    2014-01-01

    Background: With improved understanding of the biomechanical importance of the medial patellofemoral ligament (MPFL), its reconstruction for patellar dislocation has become increasingly popular. The aim of this systematic review was to critically determine the effectiveness of MPFL reconstruction for patellar dislocation. Hypothesis: MPFL reconstruction for patellar dislocation leads to a low redislocation rate with improved Kujala scores. Study Design: Systematic review; Level of evidence, 4. Methods: A literature search was performed using Embase and Medline (Ovid) databases. Inclusion criteria included first-time and recurrent patellar dislocation, subluxation, or persistent instability with a minimum follow-up of 12 months and documentation of postoperative redislocation rate or Kujala score. The studies were systematically appraised, and a meta-analysis was performed. Results: Twenty-two studies were included: 2 randomized controlled trials, 3 parallel case series, and 17 case series. There were a total of 655 knees in the review, with an age range at time of surgery from 11 to 52 years. The pooled postoperative redislocation rate from all 17 case series showed a mean of 2.44%. The pooled preoperative Kujala scores from 12 case series showed a mean of 51.6 (95% CI, 46.71-56.49). The pooled postoperative Kujala scores from 16 case series showed a mean of 87.77 (95% CI, 85.15-90.39). Conclusion: Although the studies were of low quality, the meta-analysis of 17 case series shows that MPFL reconstruction for recurrent patellar dislocation results in a significant improvement in Kujala scores, a low redislocation rate, and acceptable complication rate. Randomized trials would be needed to draw influences on the superiority of MPFL reconstruction compared with other treatments. PMID:26535352

  8. Complications Associated With Medial Thigh Lift: A Comprehensive Literature Review

    PubMed Central

    Sisti, Andrea; Cuomo, Roberto; Zerini, Irene; Tassinari, Juri; Brandi, Cesare; Grimaldi, Luca; D’Aniello, Carlo; Nisi, Giuseppe

    2015-01-01

    Medial contouring of the thigh is frequently requested to improve appearance and function of medial thigh deformities, following massive weight loss or aging process. This surgical procedure can be associated with a significant rate of complications. Our aim was to consider the complications and outcomes according to the performed technique, through a wide and comprehensive review of the literature. A search on PubMed/Medline was performed using “medial thighplasty”, “medial thigh lifting” and “technique” as key words. As inclusion criteria, we selected the clinical studies describing techniques of medial thighplasty. We excluded the papers in which complications related to medial thighplasty were not specified. We also excluded literature-review articles. We found 16 studies from 1988 to 2015. Overall, 447 patients were treated. Different techniques were applied. Complications were observed in 191/447 patients (42.72%). The most frequent complications were wound dehiscence(18.34%) and seroma (8.05%). No major complications, such as thromboembolism and sepsis, were observed. Minor complications occurred in a high percent of patients, regardless of the performed surgical procedure. Patients should be informed about the possible occurrence of wound dehiscence and seroma, as common complications associated with this surgical procedure. PMID:26865783

  9. Complications Associated With Medial Thigh Lift: A Comprehensive Literature Review.

    PubMed

    Sisti, Andrea; Cuomo, Roberto; Zerini, Irene; Tassinari, Juri; Brandi, Cesare; Grimaldi, Luca; D'Aniello, Carlo; Nisi, Giuseppe

    2015-01-01

    Medial contouring of the thigh is frequently requested to improve appearance and function of medial thigh deformities, following massive weight loss or aging process. This surgical procedure can be associated with a significant rate of complications. Our aim was to consider the complications and outcomes according to the performed technique, through a wide and comprehensive review of the literature. A search on PubMed/Medline was performed using "medial thighplasty", "medial thigh lifting" and "technique" as key words. As inclusion criteria, we selected the clinical studies describing techniques of medial thighplasty. We excluded the papers in which complications related to medial thighplasty were not specified. We also excluded literature-review articles. We found 16 studies from 1988 to 2015. Overall, 447 patients were treated. Different techniques were applied. Complications were observed in 191/447 patients (42.72%). The most frequent complications were wound dehiscence(18.34%) and seroma (8.05%). No major complications, such as thromboembolism and sepsis, were observed. Minor complications occurred in a high percent of patients, regardless of the performed surgical procedure. Patients should be informed about the possible occurrence of wound dehiscence and seroma, as common complications associated with this surgical procedure. PMID:26865783

  10. Lateral patellar facetectomy and medial reefing in patients with lateral facet syndrome after patellar-retaining total knee arthroplasty.

    PubMed

    Pagenstert, Geert; Seelhoff, Juliane; Henninger, Heath B; Wirtz, Dieter C; Valderrabano, Victor; Barg, Alexej

    2014-11-01

    We analyzed clinical outcomes of partial lateral patellar facetectomy and medial reefing in patients with lateral patellar facet syndrome with painful patellar-retaining total knee arthroplasty. 34 patients were followed for a mean of 40 months. All 34 patients were matched with those having secondary patellar resurfacing without facetectomy. Both groups experienced significant pain relief and range of motion improvement. The facetectomy group had higher Kujala scores than those in patellar resurfacing group. Patients with facetectomy had significantly less pain postoperatively. There were significant differences in postoperative lateral patellar tilt and congruency angle in both groups. The mid-term results for LPF with medial reefing are promising to resolve pain in patients with lateral patellar facet syndrome in patellar-retaining TKA. Therapeutic level III (retrospective comparative study). PMID:25070901

  11. TCDD alters medial epithelial cell differentiation during palatogenesis

    SciTech Connect

    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 is 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.

  12. Comparison of medial versus lateral meniscus allograft transplantation

    PubMed Central

    Wei, Guo; Liang, Jie; Ru, Neng; Li, Yu-Peng; Shang, Zheng-Hui; Chen, Jian-Feng

    2016-01-01

    Objectives: To perform a literature review and meta-analysis evaluating the effectiveness of medial and lateral meniscus allograft transplantation (MAT). Methods: The literature review and meta-analysis were conducted between August and October 2015 in the People’s Hospital of China Three Gorges University, Yi Chang, China. A systematic search was performed in the Medline and EMBASE databases, and the Cochrane Library for relevant literature published through October 2015. The outcomes of the included studies were analyzed in terms of the Lysholm Score, International Knee Documentation Committee (IKDC) Score, Knee Injury And Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS), Tegner Activity Score, MRI results, and failure rates. An adapted version of the Newcastle-Ottawa Scale was used for the methodological quality assessment in the meta-analyses. Results: The literature review identified 12 observational studies, including 7 retrospective studies, 4 prospective studies, and the nature of one study was not reported. Significant differences in the outcomes of the lateral MAT group and the medial MAT group were observed in the IKDC scores, KOOS pain values, KOOS activities of daily living (ADL) values, and the absolute and relative extrusions observed on MRI, which suggested that the lateral MAT patients experienced superior clinical benefits compared with the medial MAT patients. However, significant differences between the lateral MAT group and the medial MAT group were not observed with regards to the Lysholm Scores, KOOS symptom values, KOOS sports and recreations values, KOOS quality of life (QOL) values, Tegner Activity Scores, VAS for pain values, and failure rates. Conclusion: The analysis results indicated that lateral MAT provides superior clinical outcomes compared with medial MAT according to the KOOS and IKDC scores. In addition, greater graft extrusion was observed in the medial group on MRI. Although significant differences were not

  13. Protrusio After Medial Acetabular Wall Breach in Total Hip Arthroplasty

    PubMed Central

    Martin, Christopher T.; Heiner, Anneliese D.; Baer, Thomas E.; Pugely, Andrew J.; Noiseux, Nicolas O.

    2015-01-01

    Background Medial protrusio is a recognized complication of total hip arthroplasty, but it is not known if a medial wall breach during cup implantation increases the risk. We thus investigated the effect of up to a 2 cm defect in the medial acetabular wall in a cadaveric model. Separately, we investigated the ability of acetabular screws to rescue the construct. Methods Nine human fresh-frozen hemipelves were reamed medially to create the defect, implanted with acetabular cups, and then loaded to failure. The nine contralateral hemipelves were reamed in a standard fashion and served as controls. Separately, nine hemipelves with a medial defect were augmented with two acetabular screws each, then loaded to failure, with the contralateral side as a control. Load-to-failure, stiffness, and energy were recorded. Findings The presence of a medial wall defect decreased the load-to-failure by a mean of 26% (5710 v. 4221 N, p=0.024). The addition of two acetabular screws did not rescue the construct (mean 27% decrease, 4082 v. 2985 N, p=0.024). The majority of specimens failed in a supra-physiologic range of force. Bone density correlated with failure loads (R2 range of 0.54-0.78), and osteoporotic specimens were more likely to fail at a physiologic range, consistent with forces experienced during minor stumbles or falls. Interpretation Osteoporotic patients with a medial wall defect after hip arthroplasty may be susceptible to fracture during activities of daily living. Protected weight bearing with an assistive device may be reasonable in order to minimize fall risk until cup ingrowth is achieved. PMID:26361450

  14. Knee stabilization in patients with medial compartment knee osteoarthritis

    PubMed Central

    Lewek, Michael D.; Ramsey, Dan K.; Snyder-Mackler, Lynn; Rudolph, Katherine S.

    2005-01-01

    OBJECTIVE Individuals with medial knee osteoarthritis (MKOA) experience knee laxity and instability. Muscle stabilization strategies may influence the long term integrity of the joint. In this study we determined how individuals with medial knee OA respond to a rapid valgus knee movement to investigate the relationship between muscle stabilization strategies and knee instability. METHODS Twenty one subjects with MKOA and genu varum, and 19 control subjects were tested. Subjects stood with the test limb on a moveable platform that translated laterally to rapidly stress the knee’s medial periarticular structures and create a potentially destabilizing feeling at the knee joint. Knee motion and muscle responses were recorded. Subjects rated their knee instability with a self-report questionnaire about knee instability during daily activities. RESULTS Prior to plate movement the OA subjects demonstrated more medial muscle co-contraction (p=0.014). Following plate movement the OA subjects shifted less weight off the test limb (p = 0.013) and had more medial co-contraction (p=0.037). Those without instability had higher VMMH co-contraction than those who reported more instability (p=0.038). Knee stability correlated positively with VMMH co-contraction prior to plate movement (r = 0.459; p = 0.042). CONCLUSION This study demonstrates that individuals with MKOA attempt to stabilize the knee with greater medial muscle co-contraction in response to laxity that appears on only the medial side of the joint. This strategy presumably contributes to higher joint compression and could exacerbate joint destruction and needs to be altered to slow or stop the progression of the OA disease process. PMID:16142714

  15. Relationship between foot function and medial knee joint loading in people with medial compartment knee osteoarthritis

    PubMed Central

    2013-01-01

    Background Dynamic joint loading, particularly the external knee adduction moment (KAM), is an important surrogate measure for the medio-lateral distribution of force across the knee joint in people with knee osteoarthritis (OA). Foot motion may alter the load on the medial tibiofemoral joint and hence affect the KAM. Therefore, this study aimed to investigate the relationship between tibia, rearfoot and forefoot motion in the frontal and transverse planes and the KAM in people with medial compartment knee OA. Method Motion of the knee, tibia, rearfoot and forefoot and knee moments were evaluated in 32 patients with clinically and radiographically-confirmed OA, predominantly in the medial compartment. Pearson’s correlation coefficient was used to investigate the association between peak values of tibia, rearfoot and forefoot motion in the frontal and transverse planes and 1st peak KAM, 2nd peak KAM, and the knee adduction angular impulse (KAAI). Results Lateral tilt of the tibia was significantly associated with increased 1st peak KAM (r = 0.60, p < 0.001), 2nd peak KAM (r = 0.67, p = 0.001) and KAAI (r = 0.82, p = 0.001). Increased peak rearfoot eversion was significantly correlated with decreased 2nd peak KAM (r = 0.59, p < 0.001) and KAAI (r = 0.50, p = 0.004). Decreased rearfoot internal rotation was significantly associated with increased 2nd peak KAM (r = −0.44, p = 0.01) and KAAI (r = −0.38, p = 0.02), while decreased rearfoot internal rotation relative to the tibia was significantly associated with increased 2nd peak KAM (r = 0.43, p = 0.01). Significant negative correlations were found between peak forefoot eversion relative to the rearfoot and 2nd peak KAM (r = −0.53, p = 0.002) and KAAI (r = −0.51, p = 0.003) and between peak forefoot inversion and 2nd peak KAM (r = −0.54, p = 0.001) and KAAI (r = −0.48, p = 0.005). Conclusion Increased rearfoot

  16. Open Right Hemicolectomy:Lateral to Medial or Medial to Lateral Approach?

    PubMed Central

    Lin, Qi; Zhong, Yunshi; Tang, Wentao; Feng, Qingyang; Zheng, Peng; Ji, Meiling; Wei, Ye; Xu, Jianmin

    2015-01-01

    Objective Currently, no published studies have compared the clinical outcomes of the medial-to-lateral approach (MA) and lateral-to-medial approach (LA) for open right hemicolectomy. Thus, the present study aimed to assess whether one of these approaches has any potential benefits over the other. Methods A retrospective study was performed of all patients who underwent open right hemicolectomy with pathologically confirmed disease who met the eligibility criteria between June 2008 and June 2012. The population was divided into an MA group and an LA group by propensity scoring. We compared patient demographic and clinical characteristic variables between the two groups and assessed short-term and long-term outcomes. Results A total of 450 patients (MA, n = 150; LA, n = 300) were evaluated. The operation time (MA,138.4 minutesvs.LA,166.2 minutes; P < .05) and blood loss (MA,52.0mL vs. LA,62.6mL; P < .05)were significantly lower in the MA group. No differences in the number of harvested lymph nodes and oncologic outcomes were observed between the two groups. Further subgroup analysis for stage III colon cancer revealed that the MA group had significantly more retrieved lymph nodes (MA,18.8vs. LA,16.0; P = .028). There were no differences in other variables between the two groups. Conclusions The MA reduced operative time and blood loss compared with the LA. We thus concluded that the MA provided short-term benefits compared with the LA in open right hemicolectomy for right-sided colon cancer. PMID:26720634

  17. Lateral-Medial Dissociation in Orbitofrontal Cortex-Hypothalamus Connectivity.

    PubMed

    Hirose, Satoshi; Osada, Takahiro; Ogawa, Akitoshi; Tanaka, Masaki; Wada, Hiroyuki; Yoshizawa, Yasunori; Imai, Yoshio; Machida, Toru; Akahane, Masaaki; Shirouzu, Ichiro; Konishi, Seiki

    2016-01-01

    The orbitofrontal cortex (OFC) is involved in cognitive functions, and is also closely related to autonomic functions. The OFC is densely connected with the hypothalamus, a heterogeneous structure controlling autonomic functions that can be divided into two major parts: the lateral and the medial. Resting-state functional connectivity has allowed us to parcellate the cerebral cortex into putative functional areas based on the changes in the spatial pattern of connectivity in the cerebral cortex when a seed point is moved from one voxel to another. In the present high spatial-resolution fMRI study, we investigate the connectivity-based organization of the OFC with reference to the hypothalamus. The OFC was parcellated using resting-state functional connectivity in an individual subject approach, and then the functional connectivity was examined between the parcellated areas in the OFC and the lateral/medial hypothalamus. We found a functional double dissociation in the OFC: the lateral OFC (the lateral orbital gyrus) was more likely connected with the lateral hypothalamus, whereas the medial OFC (the medial orbital and rectal gyri) was more likely connected with the medial hypothalamus. These results demonstrate the fundamental heterogeneity of the OFC, and suggest a potential neural basis of the OFC-hypothalamic functional interaction. PMID:27303281

  18. Lateral–Medial Dissociation in Orbitofrontal Cortex–Hypothalamus Connectivity

    PubMed Central

    Hirose, Satoshi; Osada, Takahiro; Ogawa, Akitoshi; Tanaka, Masaki; Wada, Hiroyuki; Yoshizawa, Yasunori; Imai, Yoshio; Machida, Toru; Akahane, Masaaki; Shirouzu, Ichiro; Konishi, Seiki

    2016-01-01

    The orbitofrontal cortex (OFC) is involved in cognitive functions, and is also closely related to autonomic functions. The OFC is densely connected with the hypothalamus, a heterogeneous structure controlling autonomic functions that can be divided into two major parts: the lateral and the medial. Resting-state functional connectivity has allowed us to parcellate the cerebral cortex into putative functional areas based on the changes in the spatial pattern of connectivity in the cerebral cortex when a seed point is moved from one voxel to another. In the present high spatial-resolution fMRI study, we investigate the connectivity-based organization of the OFC with reference to the hypothalamus. The OFC was parcellated using resting-state functional connectivity in an individual subject approach, and then the functional connectivity was examined between the parcellated areas in the OFC and the lateral/medial hypothalamus. We found a functional double dissociation in the OFC: the lateral OFC (the lateral orbital gyrus) was more likely connected with the lateral hypothalamus, whereas the medial OFC (the medial orbital and rectal gyri) was more likely connected with the medial hypothalamus. These results demonstrate the fundamental heterogeneity of the OFC, and suggest a potential neural basis of the OFC–hypothalamic functional interaction. PMID:27303281

  19. Medial prefrontal theta phase coupling during spatial memory retrieval.

    PubMed

    Kaplan, Raphael; Bush, Daniel; Bonnefond, Mathilde; Bandettini, Peter A; Barnes, Gareth R; Doeller, Christian F; Burgess, Neil

    2014-06-01

    Memory retrieval is believed to involve a disparate network of areas, including medial prefrontal and medial temporal cortices, but the mechanisms underlying their coordination remain elusive. One suggestion is that oscillatory coherence mediates inter-regional communication, implicating theta phase and theta-gamma phase-amplitude coupling in mnemonic function across species. To examine this hypothesis, we used non-invasive whole-head magnetoencephalography (MEG) as participants retrieved the location of objects encountered within a virtual environment. We demonstrate that, when participants are cued with the image of an object whose location they must subsequently navigate to, there is a significant increase in 4-8 Hz theta power in medial prefrontal cortex (mPFC), and the phase of this oscillation is coupled both with ongoing theta phase in the medial temporal lobe (MTL) and perceptually induced 65-85 Hz gamma amplitude in medial parietal cortex. These results suggest that theta phase coupling between mPFC and MTL and theta-gamma phase-amplitude coupling between mPFC and neocortical regions may play a role in human spatial memory retrieval. PMID:24497013

  20. Tendinopathies Around the Elbow Part 2: Medial Elbow, Distal Biceps and Triceps Tendinopathies

    PubMed Central

    Donaldson, Oliver; Vannet, Nicola; Gosens, Taco; Kulkarni, Rohit

    2013-01-01

    In the second part of this review article the management of medial elbow tendinopathy, distal biceps and distal triceps tendinopathy will be discussed. There is a scarcity of publications concerning any of these tendinopathies. This review will summarise the current best available evidence in their management. Medial elbow tendinopathy, also known as Golfer's elbow, is up to 6 times less common than lateral elbow tendinopathy. The tendinopathy occurs in the insertion of pronator teres and flexor carpi radialis. Diagnosis is usually apparent through a detailed history and examination but care must be made to exclude other conditions affecting the ulnar nerve or less commonly the ulnar collateral ligament complex. If doubt exists then MRI/US and electrophysiology can be used. Treatment follows a similar pattern to that of lateral elbow tendinopathy. Acute management is with activity modification and topical NSAIDs. Injection therapy and surgical excision are utilised for recalcitrant cases. Distal biceps and triceps tendinopathies are very rare and there is limited evidence published. Sequelae of tendinopathy include tendon rupture and so it is vital to manage these tendinopathies appropriately in order to minimise this significant complication. Their management and that of partial tears will be considered. PMID:27582910

  1. Common medial elbow injuries in the adolescent athlete.

    PubMed

    Leahy, Ian; Schorpion, Melissa; Ganley, Theodore

    2015-01-01

    Recently there has been increased year-round sports participation among children and adolescents with limited to no rest periods. This has led to increases in pediatric repetitive stress injuries, once considered a rarity. Whether in the throwing athlete or in the athlete that experiences repetitive axial loading; increased medial tension and overload syndromes can lead to stress reactions and fractures. This occurs in the developing athlete due to the bone being weaker than the surrounding tendons and ligaments. The medial elbow is a high stress area and is susceptible to many conditions including apophysitis , avulsion fractures and ulnar collateral ligament disruption. Valgus stress can cause injury to the medial elbow which can lead to increased lateral compression, Panner's disease and osteochondral lesions of the capitellum and olecranon. The purpose of this manuscript is to review common elbow disorders in the adolescent population, outline management and highlight important features of rehabilitation. PMID:25840494

  2. Medial Arterial Calcification: An Overlooked Player in Peripheral Arterial Disease.

    PubMed

    Ho, Chin Yee; Shanahan, Catherine M

    2016-08-01

    Peripheral arterial disease (PAD) is a global health issue that is becoming more prevalent in an aging world population. Diabetes mellitus and chronic kidney disease are also on the increase, and both are associated with accelerated vascular calcification and an unfavorable prognosis in PAD. These data challenge the traditional athero-centric view of PAD, instead pointing toward a disease process complicated by medial arterial calcification. Like atherosclerosis, aging is a potent risk factor for medial arterial calcification, and accelerated vascular aging may underpin the devastating manifestations of PAD, particularly in patients prone to calcification. Consequently, this review will attempt to dissect the relationship between medial arterial calcification and atherosclerosis in PAD and identify common as well as novel risk factors that may contribute to and accelerate progression of PAD. In this context, we focus on the complex interplay between oxidative stress, DNA damage, and vascular aging, as well as the unexplored role of neuropathy. PMID:27312224

  3. Individuals' and groups' intentions in the medial prefrontal cortex.

    PubMed

    Chaminade, Thierry; Kawato, Mitsuo; Frith, Chris

    2011-11-16

    Functional MRI signal was recorded while participants perceived stimuli presented using moving dots. In two conditions of interest, the motion of dots depicted intentions: dots representing the joints of an agent performing an action, and dots representing individual agents behaving contingently. The finding of a common cluster in the posterior part of the medial frontal cortex involved in intentional action representation validates the hypothesis that perception of these two conditions requires a similar internal representation. A cluster responding to the behaving group only is found in the anterior medial frontal cortex. These results support a division of the medial frontal cortex according to social stimuli attributes, with anterior areas responding to higher-order group behaviours integrating the action of multiple individual agents. PMID:21897305

  4. Postero‐medial elbow problems in the adult athlete

    PubMed Central

    Eygendaal, D; Safran, M R

    2006-01-01

    The ligamentous, osseous, musculotendinous, and neural structures at the postero‐medial side of the elbow are at risk for various injuries in overhead athletes. The combination of valgus and extension overload during overhead activities results in tensile forces along the medial stabilising structures, with compression on the lateral compartment and shear stress posteriorly. The combination of tensile forces medially and shear forces posteriorly can result in ulnar collateral ligament (UCL) tears, flexor–pronator mass injuries, neuritis of the ulnar nerve, posterior impingement, and olecranon stress fractures. Most symptomatic conditions of the overhead athlete can be treated conservatively initially. In cases where conservative treatment is unsuccessful surgical intervention is indicated. Recent advances in arthroscopic surgical techniques and ligamentous reconstruction ensure that the prognosis for return to pre‐injury level is good. PMID:16632574

  5. Two cases of medial knee pain involving the medial coronary ligament in adolescents treated with conservative rehabilitation therapy

    PubMed Central

    Hudes, Karen

    2011-01-01

    Objective: This case study chronicled the assessment, treatment and management of two adolescent patients presenting with acute knee pain, diagnosed as medial meniscus tear, with or without a medial collateral ligament sprain, with coronary ligament involvement. Cases Patient 1: A 16 year old male football player presented with right medial knee pain of 2 days duration after having been tackled during practice from the left side. Patient 2: A 16 year old female presented with right medial knee pain that began 1 week prior to presentation after a fall down the stairs. Treatment: Treatment was initiated in both cases using inflammatory control techniques of icing and fascial stripping and progressed to rehabilitative exercises including VMO (vastus medialis oblique) exercises and squatting exercises to strengthen the quadriceps femoris musculature and proprioceptive exercise. Rehabilitation occurred over a four week duration in both cases with progression of exercises on an individual basis. Both cases resolved within four weeks and return to normal activities resumed at the three week mark including a return to play in patient 1. Both patients reported complete resolution of symptoms at the four week mark with no recurrence on follow up a number of months later. Summary: Conservative management, including icing, fascial stripping, and rehabilitative exercises may be beneficial in the treatment of medial meniscus tears with coronary ligament involvement in adolescents. PMID:21629464

  6. Tentorial dural arteriovenous fistula of the medial tentorial artery.

    PubMed

    Liu, Syrone; Lee, Dane C; Tanoura, Tad

    2016-09-01

    The medial tentorial artery arises from the meningohypophyseal trunk, a branch of the cavernous internal carotid artery, and it is poorly visualized on angiography in the absence of pathologically increased blood flow. We present the case of a 38-year-old man with intraventricular hemorrhage from a tentorial dural arteriovenous fistula (DAVF) singularly supplied by a robust medial tentorial artery. Tentorial DAVFs comprise a rare but high-risk subset of DAVFs. The diagnosis was suggested by computed tomography and magnetic resonance imaging findings and confirmed with digital subtraction angiography. PMID:27594958

  7. Bilateral medial medullary syndrome secondary to Takayasu arteritis.

    PubMed

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

    2013-01-01

    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. PMID:23943806

  8. Medial proximal tibial angle after medial opening wedge HTO: A retrospective diagnostic test study

    PubMed Central

    Pornrattanamaneewong, Chaturong; Narkbunnam, Rapeepat; Chareancholvanich, Keerati

    2012-01-01

    Background: Medial proximal tibial angle (MPTA) is the commonly used angle, which is simply measured from the knee radiographs. It can determine the correction angle in medial opening wedge high tibial osteotomy (MOWHTO). The hypothesis of our study is that post-osteotomy MPTA can predict the change in correction angle, and we aimed to determine the optimal MPTA with which to prevent recurrent varus deformity after MOWHTO. Materials and Methods: Between January 2002 and April 2010, radiographs of 59 patients, who underwent 71 MOWHTOs using the locking-compression osteotomy plates without bone grafts, were evaluated for the change of the MPTA. The MPTA was measured preoperatively and one and twelve months postoperatively. The changes of MPTA between one and twelve months were classified into valgus, stable, and varus change. The predicting factors were analyzed using analysis of variance (ANOVA) and Bonferroni multiple comparisons. The receiver operating characteristic (ROC) curve was used to find out the cut off point for preventing the recurrent varus deformity. Results: The overall preoperative, and one and twelve month postoperative MPTA values were 84.4 ± 2.4°, 97.2 ± 4.1°, and 96.3 ± 3.6°, respectively. Between one and twelve months, 39 knees displayed reduced varus change (–2.8 ± 2.1°), 18 knees displayed no change, and 14 knees displayed a greater valgus change (+2.9 ± 2.1°). The best factor for predicting these changes was the one month MPTA value (P = 0.006). By using the ROC curve, a one month MPTA of 95° was analyzed as the cut off point for preventing the recurrent varus deformity. With MPTA ≥95°, 92.3% of the osteotomies exhibited stable or varus change and 7.7% exhibited valgus change. However, with MPTA <95°, 47.4% exhibited stable or varus change and 52.6% exhibited valgus change (P < 0.001, odds ratio = 13.3). Conclusion: The postoperative MPTA can be used to predict the change in correction angle and an MPTA of at least 95° is

  9. Pituitary adenoma with seizures: PET demonstration of reduced glucose utilization in the medial temporal lobe

    SciTech Connect

    Bairamian, D.; Di Chiro, G.; Blume, H.; Ehrenberg, B.

    1986-05-01

    A patient with a benign chromophobe adenoma, who had incomplete surgical removal followed by radiotherapy, continued to have epileptic seizures up to two or three times a day. She was studied with positron emission tomography using /sup 18/F-2-deoxyglucose (FDG). This technique showed a high level of glucose utilization in the area of the operated tumor but also clear reduction of glucose utilization in the left medial temporal region adjacent to the sella and the scar tissue from the neoplasm. This area of reduced glucose utilization corresponded well to the same finding observed in other patients with complex partial epilepsy. A left temporal anterior lobectomy was carried out followed by improved control of the epilepsy. Positron emission tomography using FDG, together with electrophysiological examinations, may assist in the management of epilepsy related to pituitary tumors.

  10. Medial Posterior Meniscal Root Tears Are Associated with Development or Worsening of Medial Tibiofemoral Cartilage Damage: The Multicenter Osteoarthritis Study

    PubMed Central

    Hayashi, Daichi; Jarraya, Mohamed; Roemer, Frank W.; Zhang, Yuqing; Niu, Jingbo; Crema, Michel D.; Englund, Martin; Lynch, John A.; Nevitt, Michael C.; Torner, James C.; Lewis, Cora E.; Felson, David T.

    2013-01-01

    Purpose: To assess the association of meniscal root tear with the development or worsening of tibiofemoral cartilage damage. Materials and Methods: Institutional review board approval and written informed consent from all subjects were obtained. A total of 596 knees with radiographically depicted osteoarthritis were randomly selected from the Multicenter Osteoarthritis study cohort. Cartilage damage was semiquantitatively assessed by using the Whole-Organ Magnetic Resonance Imaging Score (WORMS) system (grades 0–6). Subjects were separated into three groups: root tear only, meniscal tear without root tear, and neither meniscal nor root tear. A log-binomial regression model was used to calculate the relative risks for knees to develop incident or progressing cartilage damage in the root tear group and the meniscal tear group, with the no tear group serving as a reference. Results: In the medial tibiofemoral joint, there were 37 knees with isolated medial posterior root tear, 294 with meniscal tear without root tear, and 264 without meniscal or root tear. There were only two lateral posterior root tears, and no anterior root tears were found. Thus, the focus was on the medial posterior root tear. The frequency of severe cartilage damage (WORMS ≥5) was higher in the group with root tear than in the group without root or meniscal tear (76.7% vs 19.7%, P < .0001) but not in the group with meniscal but no root tear (76.7% vs 65.2%, P = .055). Longitudinal analyses included 33 knees with isolated medial posterior root tear, 270 with meniscal tear, and 245 with no tear. Adjusted relative risk of cartilage loss was 2.03 (95% confidence interval [CI]: 1.18, 3.48) for the root tear group and 1.84 (95% CI: 1.32, 2.58) for the meniscal tear group. Conclusion: Isolated medial posterior meniscal root tear is associated with incident and progressive medial tibiofemoral cartilage loss. © RSNA, 2013 PMID:23696679

  11. Foot polydactyly and bipartite medial cuneiform: A case of co-occurrence in a Celtic skeleton from Verona (Italy).

    PubMed

    Laffranchi, Z; Martín Flórez, J S; Jiménez Brobeil, S A; Castellani, V

    2015-06-01

    We report a case of bilateral foot polydactyly and bipartite medial cuneiform in a male individual buried in a Celtic/Roman necropolis (3rd to 1st century BCE) in the city of Verona (Italy). During the construction of an underground garage in the main courtyard of the Bishop's Seminary at Verona between 2005 and 2010, archaeologists uncovered the remains of 174 individuals (108 non-adults and 66 adults). It is thought that these graves could belong to some of the first inhabitants of the urban area of Verona. The individual presented here (US 2807) is a middle-aged male (40-50 years) in a good state of preservation. His estimated stature is 1756 mm (± 32.1 mm). This male presents congenital anomalies in the feet and dental agenesis. We believe this to be the only known archaeological case of bilateral postaxial polydactyly with forked (Y) shape, in which both fifth metatarsals are associated with complete bipartition of the left medial cuneiform and partial bipartition of the right one. Polydactyly is fairly common in modern clinical cases but bipartite medial cuneiform is relatively rare; neither of these congenital conditions is well documented archaeologically. PMID:25813424

  12. 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…

  13. 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…

  14. Sural Versus Perforator Flaps for Distal Medial Leg Wounds.

    PubMed

    Schannen, Andrew P; Truchan, Lisa; Goshima, Kaoru; Bentley, Roger; DeSilva, Gregory L

    2015-12-01

    Soft tissue coverage of distal medial ankle wounds is a challenging problem in orthopedic surgery because of the limited local tissues and prominent instrumentation. Traditionally, these wounds required free tissue transfer to achieve suitable coverage and subsequent bony union. To better respect the reconstructive ladder and to avoid the inherent difficulty of free flap coverage, rotational flaps have been used to cover these wounds. Both sural fasciocutaneous flaps and rotational fasciocutaneous perforator (propeller) flaps have been described for distal medial soft tissue coverage. The authors performed a retrospective chart review of patients who underwent distal medial leg coverage with the use of either sural flaps or rotational fasciocutaneous perforator flaps. The authors identified 14 patients by Current Procedural Terminology code who met the study criteria. The average age and degree of medical comorbidities were comparable in the 2 groups. The authors reviewed their medical records to evaluate fracture healing, flap size, complications, and return to normal shoe wear. All 7 sural flaps healed without incident, with underlying fracture healing. Of the 7 perforator flaps, 6 healed without incident, with underlying fracture healing. One perforator-based flap was complicated by superficial tip necrosis and went on to heal with local wound care. All patients returned to normal shoe wear. Both sural artery rotational flaps and posterior tibial artery-based rotational flaps are viable options for coverage of the distal medial leg. Coverage can be achieved reliably without microsurgery, anticoagulation, or monitoring in the intensive care unit. PMID:26652325

  15. Osteochondritis dissecans on the medial aspect of the humeral head

    PubMed Central

    Mima, Yuichiro; Matsumura, Noboru; Ogawa, Kiyohisa; Iwamoto, Takuji; Ochi, Kensuke; Sato, Kazuki; Toyama, Yoshiaki

    2016-01-01

    The case of a 29-year-old man who had osteochondritis dissecans on the medial aspect of the humeral head is reported. Repetitive micro-trauma at a low elevated arm position was thought to have induced the osteochondral lesion. PMID:27186062

  16. Medial Patellofemoral Ligament Reconstruction in a Below-Knee Amputee

    PubMed Central

    El-Tawil, Sherif; Elfons Tawafig, Marian; Miles, Jonathan

    2015-01-01

    Patellar instability is a common finding in patients with below-knee amputation and yet management options are not commonly described in the literature. We describe the first reported case of a medial patellofemoral ligament reconstruction using allograft in a patient with a below-knee amputation. Clinical outcome at two-year follow-up remains very good. PMID:26579321

  17. 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…

  18. Medial Prefrontal Cortex Lesions Abolish Contextual Control of Competing Responses

    ERIC Educational Resources Information Center

    Haddon, J. E.; Killcross, A. S.

    2005-01-01

    There is much debate as to the extent and nature of functional specialization within the different subregions of the prefrontal cortex. The current study was undertaken to investigate the effect of damage to medial prefrontal cortex subregions in the rat. Rats were trained on two biconditional discrimination tasks, one auditory and one visual, in…

  19. Medial temporal N-acetyl aspartate in pediatric major depression

    PubMed Central

    MacMaster, Frank P.; Moore, Gregory J; Russell, Aileen; Mirza, Yousha; Taormina, S. Preeya; Buhagiar, Christian; Rosenberg, David R.

    2008-01-01

    The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD-case control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability. PMID:18703320

  20. Medial temporal N-acetyl-aspartate in pediatric major depression.

    PubMed

    MacMaster, Frank P; Moore, Gregory J; Russell, Aileen; Mirza, Yousha; Taormina, S Preeya; Buhagiar, Christian; Rosenberg, David R

    2008-10-30

    The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD case-control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in the left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability. PMID:18703320

  1. Scene-Selectivity and Retinotopy in Medial Parietal Cortex.

    PubMed

    Silson, Edward H; Steel, Adam D; Baker, Chris I

    2016-01-01

    Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral [occipital place area (OPA)], ventral [parahippocampal place area (PPA)], and medial [retrosplenial complex (RSC)] cortical surfaces. Recently, we demonstrated differential retinotopic biases for the contralateral lower and upper visual fields within OPA and PPA, respectively. Here, using functional magnetic resonance imaging, we combine detailed mapping of both population receptive fields (pRF) and category-selectivity, with independently acquired resting-state functional connectivity analyses, to examine scene and retinotopic processing within medial parietal cortex. We identified a medial scene-selective region, which was contained largely within the posterior and ventral bank of the parieto-occipital sulcus (POS). While this region is typically referred to as RSC, the spatial extent of our scene-selective region typically did not extend into retrosplenial cortex, and thus we adopt the term medial place area (MPA) to refer to this visually defined scene-selective region. Intriguingly MPA co-localized with a region identified solely on the basis of retinotopic sensitivity using pRF analyses. We found that MPA demonstrates a significant contralateral visual field bias, coupled with large pRF sizes. Unlike OPA and PPA, MPA did not show a consistent bias to a single visual quadrant. MPA also co-localized with a region identified by strong differential functional connectivity with PPA and the human face-selective fusiform face area (FFA), commensurate with its functional selectivity. Functional connectivity with OPA was much weaker than with PPA, and similar to that with face-selective occipital face area (OFA), suggesting a closer link with ventral than lateral cortex. Consistent with prior research, we also observed differential functional connectivity in medial parietal cortex for anterior over posterior PPA, as well as a region on the lateral

  2. Scene-Selectivity and Retinotopy in Medial Parietal Cortex

    PubMed Central

    Silson, Edward H.; Steel, Adam D.; Baker, Chris I.

    2016-01-01

    Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral [occipital place area (OPA)], ventral [parahippocampal place area (PPA)], and medial [retrosplenial complex (RSC)] cortical surfaces. Recently, we demonstrated differential retinotopic biases for the contralateral lower and upper visual fields within OPA and PPA, respectively. Here, using functional magnetic resonance imaging, we combine detailed mapping of both population receptive fields (pRF) and category-selectivity, with independently acquired resting-state functional connectivity analyses, to examine scene and retinotopic processing within medial parietal cortex. We identified a medial scene-selective region, which was contained largely within the posterior and ventral bank of the parieto-occipital sulcus (POS). While this region is typically referred to as RSC, the spatial extent of our scene-selective region typically did not extend into retrosplenial cortex, and thus we adopt the term medial place area (MPA) to refer to this visually defined scene-selective region. Intriguingly MPA co-localized with a region identified solely on the basis of retinotopic sensitivity using pRF analyses. We found that MPA demonstrates a significant contralateral visual field bias, coupled with large pRF sizes. Unlike OPA and PPA, MPA did not show a consistent bias to a single visual quadrant. MPA also co-localized with a region identified by strong differential functional connectivity with PPA and the human face-selective fusiform face area (FFA), commensurate with its functional selectivity. Functional connectivity with OPA was much weaker than with PPA, and similar to that with face-selective occipital face area (OFA), suggesting a closer link with ventral than lateral cortex. Consistent with prior research, we also observed differential functional connectivity in medial parietal cortex for anterior over posterior PPA, as well as a region on the lateral

  3. A Finite Element Analysis of Medial Patellofemoral Ligament Reconstruction

    PubMed Central

    DeVries Watson, Nicole A.; Duchman, Kyle R.; Bollier, Matthew J.; Grosland, Nicole M.

    2015-01-01

    Background The medial patellofemoral ligament is the primary soft-tissue restraint to lateral patella translation. Medial patellofemoral ligament reconstruction has become a viable surgical option to provide patellar stability in patients with recurrent instability. The primary goal of this study was to determine the effect of medial patellofemoral ligament reconstruction on the lateral force-displacement behavior of the patella using finite element analyses. Methods A finite element model of the knee was created using cadaveric image data. Experimental testing was performed to validate the computational model. After validation, the model was modified to study the effect of various medial patellofemoral ligament reconstruction insertion sites, allowing comparison of patellofemoral contact force and pressure. Results For the intact anatomic model, the lateral restraining force was 80.0 N with a corresponding patellar contact area of 54.97 mm2. For the anatomic reconstructed medial patellofemoral ligament model, the lateral restraining force increased to 148.9 N with a contact area of 71.78 mm2. This compared favorably to the corresponding experimental study. The force required to laterally displace the patella increased when the femoral insertion site was moved anteriorly or distally. The lateral restraining force decreased when the femoral insertion site moved proximally and the patellar insertion site moved either proximal or distal by 5 mm. Conclusion The line of action was altered with insertion site position, which in turn changed the amount of force it took to displace the patella laterally. Considering the model constraints, an anterior femoral attachment may over constrain the patella and increase cartilage wear due to increase contact area and restraining force. Clinical Relevance A malpositioned femoral tunnel in MPFL reconstruction could increase restraining forces and PF contact pressure, thus it is suggested to use intra-operative fluoroscopy to confirm

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

    PubMed Central

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

    2016-01-01

    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. PMID:27163099

  5. 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…

  6. 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…

  7. MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION TO TREAT RECURRENT PATELLAR DISLOCATION

    PubMed Central

    Gonçaives, Matheus Braga Jacques; Júnior, Lúcio Honório de Carvalho; Soares, Luiz Fernando Machado; Gonçaives, Tiago Jacques; dos Santos, Rogério Luciano; Pereira, Marcelo Lobo

    2015-01-01

    Objective: To present a new technique for reconstruction of the medial patellofemoral ligament (MPFL) in patients with recurrent patellar dislocation and to evaluate the clinical findings from this. Methods: Between January 2007 and January 2008, 23 patients underwent reconstruction of the MPFL with a free graft from the semitendinosus tendon. After a minimum of 24 months of follow-up, 22 patients were evaluated using the Kujala and Lysholm clinical protocols. Results: The mean follow up was 26.2 months. According to the Lysholm protocol, the patients had a mean score of 53.72 points preoperatively and 93.36 points postoperatively (p = 0.000006). According to the Kujala protocol, the mean score was 59.81 points preoperatively and 83.54 points postoperatively (p = 0.002173). Conclusion: Reconstruction of the medial patellofemoral ligament using the proposed technique showed excellent results over the short term, when evaluated by means of clinical protocols. PMID:27027005

  8. Multiple Running Speed Signals in Medial Entorhinal Cortex.

    PubMed

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

    2016-08-01

    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

  9. Partial (focal) seizure

    MedlinePlus

    ... Jacksonian seizure; Seizure - partial (focal); Temporal lobe seizure; Epilepsy - partial seizures ... Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff ... Practice . 7th ed. Philadelphia, PA: Elsevier; 2016:chap 101. ...

  10. Partial (focal) seizure

    MedlinePlus

    ... Jacksonian seizure; Seizure - partial (focal); Temporal lobe seizure; Epilepsy - partial seizures ... Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff RB, ... 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 67. ...

  11. Partial tooth gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  12. Bipartite Medial Cuneiform: Case Report and Retrospective Review of 1000 Magnetic Resonance (MR) Imaging Studies

    PubMed Central

    Chang, Geraldine H.; Chang, Eric Y.; Chung, Christine B.; Resnick, Donald L.

    2014-01-01

    Objective. To present a unique case report of a Lisfranc fracture in a patient with a bipartite medial cuneiform and to evaluate the prevalence of the bipartite medial cuneiform in a retrospective review of 1000 magnetic resonance (MR) imaging studies of the foot. Materials and Methods. Case report followed by a retrospective review of 1000 MR imaging studies of the foot for the presence or absence of a bipartite medial cuneiform. Results. The incidence of the bipartite medial cuneiform is 0.1%. Conclusion. A bipartite medial cuneiform is a rare finding but one with both clinical and surgical implications. PMID:24587806

  13. Medial and lateral pectoral nerves: course and branches.

    PubMed

    Macchi, Veronica; Tiengo, Cesare; Porzionato, Andrea; Parenti, Anna; Stecco, Carla; Mazzoleni, Francesco; De Caro, Raffaele

    2007-03-01

    During modified radical mastectomy or cosmetic surgery, denervation of the lower part of the pectoralis major frequently occurs and may reduce muscle spasm, with consequent better reconstruction of the breast. The aim of this study was to determine the relationship between the pectoral nerves and the pectoral muscles. Eight unembalmed female cadavers were dissected and vascular and radiologic studies performed. The lateral pectoral nerves showed a constant course, parallel to the thoraco-acromial vessels. They coursed for 55 +/- 7 mm inferomedially on the deep surface of pectoralis major, under its fascia. The medial pectoral nerves showed two main patterns of branching, which correlated with the extent of the costal attachments of the pectoralis minor muscles. In pattern A (56%), associated with costal attachments narrower than 6.0 cm, the nerve pierced the deep aspect of the pectoralis minor as a single trunk, ramified in the muscle, and gave some branches that appeared on the superficial aspect to enter the pectoralis major. In pattern B (44%), associated with costal attachments wider than 6.6 cm, the nerve divided before entering pectoralis minor and its branches passed through the muscle or round its lower border to reach pectoralis major. The most medial branch of the medial pectoral nerve directed to the pectoralis major muscle emerged from pectoralis minor at the third intercostal space in the midclavicular line, a mean of 10.3 cm lateral to the margin of the sternum. Knowledge of the relationship between the extent of the costal attachment of pectoralis minor and the two patterns of branching of the medial pectoral nerve may be useful when performing elective denervation of the major pectoralis muscle. PMID:16583383

  14. Arthroscopic Removal of Shotgun Pellet From Within the Medial Meniscus

    PubMed Central

    Lacy, Kyle; Cooke, Chris; Cooke, Pat; Tonnos, Frederick

    2016-01-01

    Arthroscopic techniques are effective for the removal of intra-articular bullet and metal fragments after gunshot wounds to the shoulder, hip, knee, and sacroiliac joints. Surgical removal of bullets retained within the synovial joints is indicated; lead is dissolved by synovial fluid over time, leading to proliferative synovitis, lead arthropathy, elevated serum lead levels, and lead toxicity. We present an arthroscopic technique for removal of a shotgun pellet retained within the medial meniscus. In this technique, diagnostic knee arthroscopy is initially performed, which allows for localization of the pellet within the medial meniscus. An up-biter is used to resect the inner rim of meniscus surrounding the pellet, and the pellet is removed with a grasper. This arthroscopic approach is advantageous because it allows for efficient visualization of the pellet within the meniscus, thorough visualization of all compartments of the knee, a reduction in blood loss, and a decrease in surgical morbidity to the surrounding cartilaginous, neurovascular, and soft-tissue structures. This technique may therefore be one option to address bullet fragments or shotgun pellets that are retained within the medial meniscus. PMID:27073774

  15. Medial Epicondyle Fractures in the Pediatric Overhead Athlete.

    PubMed

    Cruz, Aristides I; Steere, Joshua T; Lawrence, J Todd R

    2016-06-01

    The medial epicondyle serves as the proximal attachment of the medial ulnar collateral ligament and the origin of the flexor pronator musculature and as such it is responsible for resisting the main static and dynamic restraints to valgus force at the elbow. Fractures through the physis in the developing elbow are common and treatment remains controversial. Biomechanical modeling predicts that anterior should be the direction of greatest displacement. Anatomic considerations predict that anterior displacement should have the greatest effect on elbow stability and range of motion making the ulnar collateral ligament too loose in flexion and too tight in extension and potentially leading to valgus laxity in flexion and a block to full extension. In the elite overhead athlete, where elbow stability is critical both for sports performance and the long-term health of the elbow, assessment of anterior displacement is thus theoretically an important consideration. Standard radiographic views cannot adequately assess anterior displacement. Specialized radiographs and 3-dimensional modalities such as computerized tomography and magnetic resonance imaging can adequately assess anterior displacement and in the overhead athlete can sometimes aid in the decision-making process. Here, we present a review of the current literature and the rationale for a treatment algorithm for medial epicondyle fractures in the skeletally immature overhead athlete. PMID:27100037

  16. 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. PMID:27484043

  17. 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.

  18. Boundary and medial shape analysis of the hippocampus in schizophrenia.

    PubMed

    Styner, Martin; Lieberman, Jeffrey A; Pantazis, Dimitrios; Gerig, Guido

    2004-09-01

    Statistical shape analysis has become of increasing interest to the neuroimaging community due to its potential to precisely locate morphological changes and thus potentially discriminate between healthy and pathological structures. This paper describes a combined boundary and medial shape analysis based on two different shape descriptions applied to a study of the hippocampus shape abnormalities in schizophrenia. The first shape description is the sampled boundary implied by the spherical harmonic SPHARM description. The second one is the medial shape description called M-rep. Both descriptions are sampled descriptions with inherent point correspondence. Their shape analysis is based on computing differences from an average template structure analyzed using standard group mean difference tests. The results of the global and local shape analysis in the presented hippocampus study exhibit the same patterns for the boundary and the medial analysis. The results strongly suggest that the normalized hippocampal shape of the schizophrenic group is different from the control group, most significantly as a deformation difference in the tail region. PMID:15450215

  19. 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.

  20. Soft-Tissue Loop for Medial Patellofemoral Ligament Reconstruction.

    PubMed

    Miswan, Mohd Fairudz Bin Mohd; Al-Fayyadh, Mohamed Zubair Mohamed; Seow Hui, Teo; Mohamed Ali, Mohamed Razif Bin; Ng, Wuey Min

    2016-04-01

    A patient with patellar instability frequently presents with anterior knee pain, patellar subluxation, or dislocation. Medial patellofemoral ligament (MPFL) has a key role for normal patella tracking and stability. Reconstruction of the MPFL using a hamstring graft is a commonly used procedure for the treatment of chronic lateral subluxation of patella. Anchor sutures and bony tunnels are used for the patellar attachment of the graft. This can be associated with complications such as patella fracture; besides, it does not produce an anatomical reconstruction for the native MPFL that can alter the direction of tension applied on the patella. To overcome these problems, a soft-tissue loop technique is used for MPFL reconstruction. During this procedure, a semitendinosus graft was passed through the prepatellar extensor retinaculum and secured with sutures. The free ends of the graft were then passed between the second and third layers of the medial patellofemoral retinaculum and fixed to a femoral tunnel on the medial femoral condyle with an interference screw. The desired amount of tension on the graft is achieved under direct vision of patella tracking arthroscopically. We found this method to be relatively safe and fast. It is more anatomical and can avoid the complications during the conventional bony procedures. PMID:27354953

  1. [Adult lateral meniscus].

    PubMed

    Beaufils, P; Hardy, P; Chambat, P; Clavert, P; Djian, P; Frank, A; Hulet, C; Potel, J-F; Verdonk, R

    2006-09-01

    Meniscal lesion does not mean meniscectomy and this is particularly true for the lateral meniscus. The reputation of mildness of the meniscectomy is usurped. The rate of joint space narrowing after lateral meniscectomy is of 40% at a follow-up of 13 years compared to 28% for the medial meniscus (symposium SFA 1996). Several arguments explain those results: biomechanical: the lateral meniscus contributes to the congruence; particularly the lateral meniscus is the zone where antero-posterior translational during knee flexion is 12 mm. The pejorative effects of lateral meniscectomy have conducted, more though to the medial meniscus, to the concept of meniscal economy. Lateral meniscectomy must be as partial as possible. Particularly, a discoid meniscus presenting a complete tear should be treated by a meniscoplasty in order to shape the meniscus in a more anatomic form than a total meniscectomy. Lateral meniscectomy is indicated in complex or horizontal cleavage, symptomatic, on stable knees. A particular case is the cyst of the lateral meniscus. It is a cystic subcutaneous formation, usual consequence of a horizontal cleaved meniscus of which the particularity is that it opens besides the articulation. The strategy must not consist in the isolated treatment of the cyst. This pathology should be addressed by an arthroscopic meniscectomy reaching the meniscosynovial junction at the level of the cyst. Meniscal repair must be proposed every time if possible. Criteria of reparability are better studied on MRI. Preoperatively MRI is the first choice radiological exam. Two essential indications can be held back: the vertical peripheral longitudinal lesion is on the non-vascularized area, and the horizontal cleaving of the junior athlete (if the cleaving remains purely intra meniscal). Meniscal repair is highly performed when the meniscal tear is associated to a rupture of the ACL (simultaneous reconstruction of the LCA). Postoperative outcome is different of that of a

  2. Bilateral Laparoscopic Partial Nephrectomies: A Case Report

    PubMed Central

    Panuganti, Sravan; Kavoussi, Louis Raphael

    2015-01-01

    Abstract Although laparoscopy is a recognized operative approach to the management of renal masses, there is currently no standardized approach to manage bilateral synchronous renal masses. We present a case of synchronous bilateral renal masses, identified during work-up for flank pain, and managed simultaneously with laparoscopic partial nephrectomies. The patient is a 42-year-old Caucasian male found to have bilateral renal masses during evaluation for left flank pain. Cross-sectional imaging studies showed a 7.0 × 7.3 × 5.2 cm anterior, mid-to-lower pole mass on the left kidney and a 1.5 × 1.9 × 1.6 cm medial lower pole mass on the right kidney. He underwent bilateral laparoscopic partial nephrectomy at the same setting, with an uncomplicated postoperative course. Pathology report revealed clear cell renal-cell carcinoma (ccRCC) on both sides. He had normal renal function and no evidence of recurrence in the first 6 months of follow-up. This case demonstrates the possibility and safety of performing bilateral laparoscopic partial nephrectomies in one operative session. Our review of the literature supports the role of genetic counseling and the need for long-term surveillance in young patients having RCC.

  3. Multimodal intervention in older adults improves resting-state functional connectivity between the medial prefrontal cortex and medial temporal lobe†

    PubMed Central

    Li, Rui; Zhu, Xinyi; Yin, Shufei; Niu, Yanan; Zheng, Zhiwei; Huang, Xin; Wang, Baoxi; Li, Juan

    2014-01-01

    The prefrontal cortex and medial temporal lobe are particularly vulnerable to the effects of aging. The disconnection between them is suggested to be an important cause of cognitive decline in normal aging. Here, using multimodal intervention training, we investigated the functional plasticity in resting-state connectivity of these two regions in older adults. The multimodal intervention, comprised of cognitive training, Tai Chi exercise, and group counseling, was conducted to explore the regional connectivity changes in the default-mode network, as well as changes in prefrontal-based voxel-wise connectivity in the whole brain. Results showed that the intervention selectively affected resting-state functional connectivity between the medial prefrontal cortex and medial temporal lobe. Moreover, the strength of resting-state functional connectivity between these regions correlated with individual cognitive performance. Our results suggest that multimodal intervention could postpone the effects of aging and improve the function of the regions that are most heavily influenced by aging, as well as play an important role in preserving the brain and cognition during old age. PMID:24653698

  4. A Novel Medial Soft Tissue Release Method for Varus Deformity during Total Knee Arthroplasty: Femoral Origin Release of the Medial Collateral Ligament

    PubMed Central

    Lee, Seung-Yup; Yang, Jae-Hyuk; Lee, Yong-In

    2016-01-01

    Introduction Numerous methods of medial soft tissue release for severe varus deformity during total knee arthroplasty (TKA) have been reported. These include tibial stripping of the superficial medial collateral ligament (MCL), pie-crusting technique, and medial epicondylar osteotomy. However, there are inherent disadvantages in these techniques. Authors hereby present a novel quantitative method: femoral origin release of the medial collateral ligament (FORM). Surgical Technique For medial tightness remaining even after the release of the deep MCL and semimembranosus, the FORM is initiated with identification of the femoral insertion area of the MCL with the knee in flexion. Starting from the most posterior part of the femoral insertion, one third of the MCL femoral insertion is released from its attachment. If necessary, further sequential medial release is performed. Materials and Methods Seventeen knees that underwent the FORM were evaluated for radiological and clinical outcomes. Results Regardless of the extent of the FORM, no knees showed residual valgus instability at 24 weeks after surgery. Conclusions As the FORM is performed in a stepwise manner, fine adjustment during medial release might be beneficial to prevent inadvertent over-release of the medial structures of the knee. PMID:27274473

  5. 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

  6. Dendritic Organization of Olfactory Inputs to Medial Amygdala Neurons.

    PubMed

    Keshavarzi, Sepideh; Power, John M; Albers, Eva H H; Sullivan, Robert K S; Sah, Pankaj

    2015-09-23

    The medial amygdala (MeA) is a central hub in the olfactory neural network. It receives vomeronasal information directly from the accessory olfactory bulb (AOB) and main olfactory information largely via odor-processing regions such as the olfactory cortical amygdala (CoA). How these inputs are processed by MeA neurons is poorly understood. Using the GAD67-GFP mouse, we show that MeA principal neurons receive convergent AOB and CoA inputs. Somatically recorded AOB synaptic inputs had slower kinetics than CoA inputs, suggesting that they are electrotonically more distant. Field potential recording, pharmacological manipulation, and Ca(2+) imaging revealed that AOB synapses are confined to distal dendrites and segregated from the proximally located CoA synapses. Moreover, unsynchronized AOB inputs had significantly broader temporal summation that was dependent on the activation of NMDA receptors. These findings show that MeA principal neurons process main and accessory olfactory inputs differentially in distinct dendritic compartments. Significance statement: In most vertebrates, olfactory cues are processed by two largely segregated neural pathways, the main and accessory olfactory systems, which are specialized to detect odors and nonvolatile chemosignals, respectively. Information from these two pathways ultimately converges at higher brain regions, one of the major hubs being the medial amygdala. Little is known about how olfactory inputs are processed by medial amygdala neurons. This study shows that individual principal neurons in this region receive input from both pathways and that these synapses are spatially segregated on their dendritic tree. We provide evidence suggesting that this dendritic segregation leads to distinct input integration and impact on neuronal output; hence, dendritic mechanisms control olfactory processing in the amygdala. PMID:26400933

  7. Voice Outcome after Gore-Tex Medialization Thyroplasty

    PubMed Central

    Elnashar, Ismail; El-Anwar, Mohammad; Amer, Hazem; Quriba, Amal

    2015-01-01

    Introduction Although medialization thyroplasty utilizing Gore-Tex (Gore and Associates, Newark, Delaware, United States) has been discussed in the literature, few reports have assessed voice quality afterward, and they did not use a full assessment protocol. Objective To assess the improvement in voice quality after medialization thyroplasty utilizing Gore-Tex in patients with glottic insufficiency of variable etiology. Methods Eleven patients with glottic insufficiency of different etiologies that failed compensation were operated by type 1 thyroplasty utilizing Gore-Tex. Pre- and postoperative (1 week, 3 months, and 6 months) voice assessment was done and statistical analysis was performed on the results. Results In all postoperative assessments, there was significant improvement in the grade of dysphonia (p < 0.004) and highly significant reduction in the size of glottic gap and prolongation of maximum phonation time (p < 0.0001). The difference in voice parameters in the early (1 week) and the late (3 and 6 months) postoperative period was not significant. None of the patients developed stridor or shortness of breath necessitating tracheotomy, and there was no implant extrusion in any patient during the study period. Conclusion Gore-Tex medialization provides reliable results for both subjective and objective voice parameters. It leads to a satisfactory restoration of voice whatever the etiology of glottic incompetence is. This technique is relatively easy and does not lead to major complications. Further studies with larger number of patients and more extended periods of follow-up are still required to assess the long-term results of the technique regarding voice quality and implant extrusion. PMID:26157500

  8. Voice Outcome after Gore-Tex Medialization Thyroplasty.

    PubMed

    Elnashar, Ismail; El-Anwar, Mohammad; Amer, Hazem; Quriba, Amal

    2015-07-01

    Introduction Although medialization thyroplasty utilizing Gore-Tex (Gore and Associates, Newark, Delaware, United States) has been discussed in the literature, few reports have assessed voice quality afterward, and they did not use a full assessment protocol. Objective To assess the improvement in voice quality after medialization thyroplasty utilizing Gore-Tex in patients with glottic insufficiency of variable etiology. Methods Eleven patients with glottic insufficiency of different etiologies that failed compensation were operated by type 1 thyroplasty utilizing Gore-Tex. Pre- and postoperative (1 week, 3 months, and 6 months) voice assessment was done and statistical analysis was performed on the results. Results In all postoperative assessments, there was significant improvement in the grade of dysphonia (p < 0.004) and highly significant reduction in the size of glottic gap and prolongation of maximum phonation time (p < 0.0001). The difference in voice parameters in the early (1 week) and the late (3 and 6 months) postoperative period was not significant. None of the patients developed stridor or shortness of breath necessitating tracheotomy, and there was no implant extrusion in any patient during the study period. Conclusion Gore-Tex medialization provides reliable results for both subjective and objective voice parameters. It leads to a satisfactory restoration of voice whatever the etiology of glottic incompetence is. This technique is relatively easy and does not lead to major complications. Further studies with larger number of patients and more extended periods of follow-up are still required to assess the long-term results of the technique regarding voice quality and implant extrusion. PMID:26157500

  9. The UniSpacer™: correcting varus malalignment in medial gonarthrosis.

    PubMed

    Clarius, Michael; Becker, Justus F; Schmitt, Holger; Seeger, Joern B

    2010-12-01

    While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA) or high tibial osteotomy (HTO), there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a self-centering, metallic interpositional device for the knee. This study evaluates clinical and radiological results of the UniSpacer™, whether alignment correction can be achieved by UniSpacer™ arthroplasty and alignment change in the first five postoperative years. Anteroposterior long leg stance radiographs of 20 legs were digitally analysed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analysed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analysing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7 ± 1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation. Our results show that good clinical and functional results can be achieved after UniSpacer™ arthroplasty. However, four of 19 knees had to be revised to a TKA or UKA due to persistent pain, which is an unacceptably high revision rate when looking at the alternative treatment options of medial osteoarthritis of the knee. PMID:19946773

  10. Technique, indications, and results of proximal medial gastrocnemius lengthening.

    PubMed

    Barouk, Pierre

    2014-12-01

    Gastrocnemius proximal lengthening was first performed to correct spasticity in children, and was adapted for the patient with no neuromuscular condition in the late 1990s. Since then, the proximal gastrocnemius release has become less invasive and has evolved to include only the fascia overlying the medial head of the gastrocnemius muscle. The indications for performing this procedure are a clinically demonstrable gastrocnemius contracture that influences a variety of clinical conditions in the forefoot, hindfoot, and ankle. It is a safe and easy procedure that can be performed bilaterally simultaneously, and does not require immobilization of the ankle after surgery. PMID:25456723

  11. Considerations for the Management of Medial Orbital Wall Blowout Fracture

    PubMed Central

    Park, Youngsoo; Chung, Kyu Jin

    2016-01-01

    Recently, diagnoses of and operations for medial orbital blowout fracture have increased because of the development of imaging technology. In this article, the authors review the literature, and overview the accumulated knowledge about the orbital anatomy, fracture mechanisms, surgical approaches, reconstruction materials, and surgical methods. In terms of surgical approaches, transcaruncular, transcutaneous, and transnasal endoscopic approaches are discussed. Reconstruction methods including onlay covering, inlay implantation, and repositioning methods are also discussed. Consideration and understanding of these should lead to more optimal outcomes. PMID:27218019

  12. Sensory conduction in medial and lateral plantar nerves.

    PubMed Central

    Ponsford, S N

    1988-01-01

    A simple and reliable method of recording medial and lateral plantar nerve sensory action potentials is described. Potentials are recorded with surface electrodes at the ankle using surface electrodes stimulating orthodromically at the sole. The normal values obtained are higher in amplitude than those obtained by the method described by Guiloff and Sherratt and are detectable in older subjects aged over 80 years. The procedure is valuable in the diagnosis of early peripheral neuropathy, mononeuritis multiplex, tarsal tunnel syndrome and in differentiation between pre and post ganglionic L5 S1 lesions. PMID:2831304

  13. Considerations for the Management of Medial Orbital Wall Blowout Fracture.

    PubMed

    Kim, Yong-Ha; Park, Youngsoo; Chung, Kyu Jin

    2016-05-01

    Recently, diagnoses of and operations for medial orbital blowout fracture have increased because of the development of imaging technology. In this article, the authors review the literature, and overview the accumulated knowledge about the orbital anatomy, fracture mechanisms, surgical approaches, reconstruction materials, and surgical methods. In terms of surgical approaches, transcaruncular, transcutaneous, and transnasal endoscopic approaches are discussed. Reconstruction methods including onlay covering, inlay implantation, and repositioning methods are also discussed. Consideration and understanding of these should lead to more optimal outcomes. PMID:27218019

  14. Second-Look Arthroscopic Assessment and Clinical Results of Modified Pull-Out Suture for Posterior Root Tear of the Medial Meniscus

    PubMed Central

    Song, Jae-Gwang

    2014-01-01

    Purpose To identify the structural integrity of the healing site after arthroscopic repair of a posterior root tear of the medial meniscus by second-look arthroscopy and to determine the clinical relevance of the findings. Materials and Methods From January 2005 to December 2010, 20 consecutive patients underwent arthroscopic modified pull-out suture repair for a posterior root tear of the medial meniscus. Thirteen patients were available for second-look arthroscopic evaluation. The healing status of the medial meniscus was classified as complete healing, lax healing, scar tissue healing, and failed healing. We evaluated the correlation between the clinical symptoms and second-look arthroscopic findings. Clinical evaluation was based on the Lysholm knee scores and Hospital for Special Surgery (HSS) scores. Results There were 4 cases of complete healing, 4 lax healing, 4 scar tissue healing, and 1 failed healing. The healing status of the repaired meniscus appeared to be related to the clinical symptoms. Patients who achieved complete tissue healing had no complaint. The healing status exhibited no relationship with age, mechanical axis, degree of subluxation, and symptom duration. The mean Lysholm score improved from 34.7 preoperatively to 75.6 at follow-up and the mean HSS score also significantly increased from 33.5 to 82.2. Conclusions We achieved 4 complete and 8 partial healing (lax or scar) of the medial meniscus in this retrospective case series of posterior horn meniscus root repairs performed by 1 surgeon. Further research is needed to clarify why all patients showed clinical improvement despite findings of partial healing on second-look arthroscopy. PMID:24944976

  15. Observing accidental and intentional unusual actions is associated with different subregions of the medial frontal cortex.

    PubMed

    Desmet, Charlotte; Brass, Marcel

    2015-11-15

    The literature on action observation revealed contradictory results regarding the activation of different subregions of the medial prefrontal cortex when observing unusual behaviour. Error observation research has shown that the posterior part of the medial prefrontal cortex is more active when observing unusual behaviour compared to usual behaviour while action understanding research has revealed some mixed results concerning the role of the anterior part of the medial prefrontal cortex during the observation of unusual actions. Here, we resolve this discrepancy in the literature by showing that different parts of the medial prefrontal cortex are active depending on whether an observed unusual behaviour is intentional or not. While the posterior medial prefrontal cortex is more active when we observe unusual accidental actions compared to unusual intentional actions, a more anterior part of the medial prefrontal cortex is more active when we observe unusual intentional actions compared to unusual accidental actions. PMID:26279209

  16. 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. PMID:27026652

  17. Increased Intrinsic Activity of Medial-Temporal Lobe Subregions is Associated with Decreased Cortical Thickness of Medial-Parietal Areas in Patients with Alzheimer's Disease Dementia.

    PubMed

    Pasquini, Lorenzo; Scherr, Martin; Tahmasian, Masoud; Myers, Nicholas E; Ortner, Marion; Kurz, Alexander; Förstl, Hans; Zimmer, Claus; Grimmer, Timo; Akhrif, Atae; Wohlschläger, Afra M; Riedl, Valentin; Sorg, Christian

    2016-01-21

    In Alzheimer's disease (AD), disrupted connectivity between medial-parietal cortices and medial-temporal lobes (MTL) is linked with increased MTL local functional connectivity, and parietal atrophy is associated with increased MTL memory activation. We hypothesized that intrinsic activity in MTL subregions is increased and associated with medial-parietal degeneration and impaired memory in AD. To test this hypothesis, resting-state-functional and structural-MRI was assessed in 22 healthy controls, 22 mild cognitive impairment patients, and 21 AD-dementia patients. Intrinsic activity was measured by power-spectrum density of blood-oxygenation-level-dependent signal, medial-parietal degeneration by cortical thinning. In AD-dementia patients, intrinsic activity was increased for several right MTL subregions. Raised intrinsic activity in dentate gyrus and cornu ammonis 1 was associated with cortical thinning in posterior cingulate cortices, and at-trend with impaired delayed recall. Critically, increased intrinsic activity in the right entorhinal cortex was associated with ipsilateral posterior cingulate degeneration. Our results provide evidence that in AD, intrinsic activity in MTL subregions is increased and associated with medial-parietal atrophy. Results fit a model in which medial-parietal degeneration contributes to MTL dysconnectivity from medial-parietal cortices, potentially underpinning disinhibition-like changes in MTL activity. PMID:26836175

  18. Reconstruction of medial patellofemoral ligament using quadriceps tendon combined with reconstruction of medial patellotibial ligament using patellar tendon: initial experience☆

    PubMed Central

    Hinckel, Betina Bremer; Gobbi, Riccardo Gomes; Bonadio, Marcelo Batista; Demange, Marco Kawamura; Pécora, José Ricardo; Camanho, Gilberto Luis

    2016-01-01

    Objective To describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series. Method The proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC-IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM), apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from 0 to 10) and whether they would be prepared to go through this operation again. Results Seven knees were operated, in seven patients, with a mean follow-up of 5.46 months (±2.07). Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound. Conclusion Reconstruction of the medial patellofemoral ligament

  19. Medial prefrontal cortex role in recognition memory in rodents.

    PubMed

    Morici, Juan Facundo; Bekinschtein, Pedro; Weisstaub, Noelia V

    2015-10-01

    The study of the neurobiology of recognition memory, defined by the integration of the different components of experiences that support recollection of past experiences have been a challenge for memory researches for many years. In the last twenty years, with the development of the spontaneous novel object recognition task and all its variants this has started to change. The features of recognition memory include a particular object or person ("what"), the context in which the experience took place, which can be the arena itself or the location within a particular arena ("where") and the particular time at which the event occurred ("when"). This definition instead of the historical anthropocentric one allows the study of this type of episodic memory in animal models. Some forms of recognition memory that require integration of different features recruit the medial prefrontal cortex. Focusing on findings from spontaneous recognition memory tasks performed by rodents, this review concentrates on the description of previous works that have examined the role that the medial prefrontal cortex has on the different steps of recognition memory. We conclude that this structure, independently of the task used, is required at different memory stages when the task cannot be solved by a single item strategy. PMID:26115848

  20. Medial Foot Loading on Ankle and Knee Biomechanics

    PubMed Central

    Mitchell, Lyneil C.J.; Ford, Kevin R.; Minning, Stephen; Myer, Gregory D.; Mangine, Robert E.

    2008-01-01

    Background The incidence of anterior cruciate ligament (ACL) injuries among females continues at disproportionate rates compared to males, with research indicating inconclusive multifactorial causality. Data from previous retrospective studies suggest an effect of abnormal foot and ankle bio-mechanics on pathology at the knee, including the ACL. Objective To determine if a relationship exists between plantar foot loading patterns during normal gait and high risk biomechanics purported to increase risk of ACL injury. Methods Dynamic barefoot plantar pressure distribution was measured on 33 female collegiate soccer players. Groups were divided according to their predominant gait loading pattern (medial or lateral). Three dimensional (3-D) motion analysis was conducted during drop vertical jumps to assess vertical ground reaction force and discrete angle and joint moment variables of the lower extremities. Results No significant differences occured in sagittal or coronal plane knee joint kinematics and kinetics between the medial and lateral loading groups. Discussion Dynamic foot and ankle biomechanics during gait do not appear to be related to lower extremity kinematics or kinetics during landing in collegiate female soccer players. Conclusion The exact cause of the abnormal differences in female landing biomechanics has not been irrefutably defined. This study suggests no effect of foot and ankle biomechanics exists on the landing mechanics of female soccer players. PMID:20379384

  1. Iatrogenic Injury to Medial Rectus After Endoscopic Sinus Surgery.

    PubMed

    Mukherjee, Bipasha; Priyadarshini, Omega; Ramasubramanian, Srikanth; Agarkar, Sumita

    2015-12-01

    Endoscopic sinus surgery (ESS) is the mainstay of the treatment in sinus disorders, to re-establish the drainage of the affected sinus. The close proximity of the orbital structures to paranasal sinuses makes them vulnerable to inadvertent injury during the sinus surgery. Medial rectus (MR) muscle is the most commonly injured extraocular muscle during ESS due to its anatomic proximity to the thin medial wall of the orbit. This is a non-comparative, retrospective, interventional case series of six patients presenting with MR injury after ESS. We discuss the management, outcome and review the published literature. A total of six patients met the inclusion criteria. The presenting complaints were diplopia, squinting and limitation of ocular movements. Two patients underwent surgical exploration of the MR muscle and reattachment of the muscle along with injection botulinum to the antagonist lateral rectus muscle. Two patients who had small angle strabismus and who were able to fuse were advised orthoptic exercises and prisms as management. Remaining two patients were advised surgical intervention to correct strabismus but they declined further surgical intervention. Management of MR injury following ESS is complex, often resulting in suboptimal outcomes. Since early intervention is associated with better outcomes, early referral by otolaryngologists to ophthalmologists would result in better outcome. PMID:26693458

  2. MRI parcellation of ex vivo medial temporal lobe.

    PubMed

    Augustinack, Jean C; Magnain, Caroline; Reuter, Martin; van der Kouwe, André J W; Boas, David; Fischl, Bruce

    2014-06-01

    Recent advancements in radio frequency coils, field strength and sophisticated pulse sequences have propelled modern brain mapping and have made validation to biological standards - histology and pathology - possible. The medial temporal lobe has long been established as a pivotal brain region for connectivity, function and unique structure in the human brain, and reveals disconnection in mild Alzheimer's disease. Specific brain mapping of mesocortical areas affected with neurofibrillary tangle pathology early in disease progression provides not only an accurate description for location of these areas but also supplies spherical coordinates that allow comparison between other ex vivo cases and larger in vivo datasets. We have identified several cytoarchitectonic features in the medial temporal lobe with high resolution ex vivo MRI, including gray matter structures such as the entorhinal layer II 'islands', perirhinal layer II-III columns, presubicular 'clouds', granule cell layer of the dentate gyrus as well as lamina of the hippocampus. Localization of Brodmann areas 28 and 35 (entorhinal and perirhinal, respectively) demonstrates MRI based area boundaries validated with multiple methods and histological stains. Based on our findings, both myelin and Nissl staining relate to contrast in ex vivo MRI. Precise brain mapping serves to create modern atlases for cortical areas, allowing accurate localization with important applications to detecting early disease processes. PMID:23702414

  3. Medial Orbitofrontal Cortex Is Associated with Fatigue Sensation

    PubMed Central

    Tajima, Seiki; Yamamoto, Shigeyuki; Tanaka, Masaaki; Kataoka, Yosky; Iwase, Masao; Yoshikawa, Etsuji; Okada, Hiroyuki; Onoe, Hirotaka; Tsukada, Hideo; Kuratsune, Hirohiko; Ouchi, Yasuomi; Watanabe, Yasuyoshi

    2010-01-01

    Fatigue is an indispensable bioalarm to avoid exhaustive state caused by overwork or stresses. It is necessary to elucidate the neural mechanism of fatigue sensation for managing fatigue properly. We performed H2 15O positron emission tomography scans to indicate neural activations while subjects were performing 35-min fatigue-inducing task trials twice. During the positron emission tomography experiment, subjects performed advanced trail-making tests, touching the target circles in sequence located on the display of a touch-panel screen. In order to identify the brain regions associated with fatigue sensation, correlation analysis was performed using statistical parametric mapping method. The brain region exhibiting a positive correlation in activity with subjective sensation of fatigue, measured immediately after each positron emission tomography scan, was located in medial orbitofrontal cortex (Brodmann's area 10/11). Hence, the medial orbitofrontal cortex is a brain region associated with mental fatigue sensation. Our findings provide a new perspective on the neural basis of fatigue. PMID:21188225

  4. Medial Meniscus Posterior Root Tear: A Comprehensive Review

    PubMed Central

    Lee, Dhong Won; Ha, Jeong Ku

    2014-01-01

    Damage to the medial meniscus root, for example by a complete radial tear, destroys the ability of the knee to withstand hoop strain, resulting in contact pressure increases and kinematic alterations. For these reasons, several techniques have been developed to repair the medial meniscus posterior root tear (MMPRT), many of which have shown complete healing of the repaired MMPRT. However, efforts to standardize or optimize the treatment for MMPRT are much needed. When planning a surgical intervention for an MMPRT, strict surgical indications regarding the effect of pullout strength on the refixed root, bony degenerative changes, mechanical alignment, and the Kellgren-Lawrence grade should be considered. Although there are several treatment options and controversies, the current trend is to repair the MMPRT using various techniques including suture anchors and pullout sutures if the patient meets the indications. However, there are still debates on the restoration of hoop tension and prevention of arthritis after repair and further biomechanical and clinical studies should be conducted in the future. The aim of this article was to review and summarize the recent literature regarding various diagnosis and treatment strategies of MMPRT, especially focusing on conflict issues including whether repair techniques can restore the main function of normal meniscus and which is the best suture technique to repair the MMPRT. The authors attempted to provide a comprehensive review of previous studies ranging from basic science to current surgical techniques. PMID:25229041

  5. Is the Medial Prefrontal Cortex Necessary for Theory of Mind?

    PubMed Central

    Otti, Alexander; Wohlschlaeger, Afra M.; Noll-Hussong, Michael

    2015-01-01

    Background Successful social interaction relies on the ability to attribute mental states to other people. Previous functional neuroimaging studies have shown that this process, described as Theory of Mind (ToM) or mentalization, is reliably associated with activation of the medial prefrontal cortex (mPFC). However, this study presents a novel and surprising finding that provides new insight into the role of the mPFC in mentalization tasks. Methodology/Principal Findings Twenty healthy individuals were recruited from a wide range of ages and social backgrounds. Participants underwent functional magnetic resonance imaging (fMRI) while viewing a well-established ToM visual paradigm involving moving triangles. Functional MRI data were analyzed using a classical general linear model. No activation was detected in the medial prefrontal cortex (mPFC) during movement patterns that typically elicit ToM. However, increased activity was observed in the right middle occipital gyrus, right temporoparietal junction (TPJ), left middle occipital gyrus and right inferior frontal gyrus. No correlation was found between participants’ age and BOLD response. Conclusions/Significance In contrast with previous neuroimaging research, our findings support the notion that mPFC function is not critical for reasoning about the mental states of others; furthermore, our data indicate that the right TPJ and right inferior frontal gyrus are able to perform mentalization without any contributions from the mPFC. PMID:26301900

  6. Partial Facetectomy for Lumbar Foraminal Stenosis

    PubMed Central

    Kang, Kevin; Rodriguez-Olaverri, Juan Carlos; Razi, Afshin; Farcy, Jean Pierre

    2014-01-01

    Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57%) reported no back pain and no functional limitations. Eight of 47 patients (17%) reported moderate pain, but had no limitations. Six of 47 patients (13%) continued to experience degenerative symptoms. Five of 47 patients (11%) required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability. PMID:25110591

  7. Physics of Partially Ionized Plasmas

    NASA Astrophysics Data System (ADS)

    Krishan, Vinod

    2016-05-01

    Figures; Preface; 1. Partially ionized plasmas here and everywhere; 2. Multifluid description of partially ionized plasmas; 3. Equilibrium of partially ionized plasmas; 4. Waves in partially ionized plasmas; 5. Advanced topics in partially ionized plasmas; 6. Research problems in partially ionized plasmas; Supplementary matter; Index.

  8. A Case of Spontaneous Osteonecrosis of the Knee with Early and Simultaneous Involvement of the Medial Femoral Condyle and Medial Tibial Plateau.

    PubMed

    Fujita, Shinya; Arai, Yuji; Honjo, Kuniaki; Nakagawa, Shuji; Kubo, Toshikazu

    2016-01-01

    Spontaneous osteonecrosis of the knee (SPONK) usually involves a single condyle, most often the medial femoral condyle (MFC). Involvement of the medial tibial plateau (MTP) is less common, occurring in about 2% of knees with SPONK. Early onset SPONK on the ipsilateral side of the medial compartment is very rare, with, to our knowledge, only four cases reported to date. We describe a very rare case of SPONK with early simultaneous development in the MFC and MTP. Serial plain radiographs and magnetic resonance imaging showed that SPONK in both condyles followed a similar progressive course. The pathological findings in these lesions were similar to those observed in subchondral insufficiency fractures. PMID:27242941

  9. A Case of Spontaneous Osteonecrosis of the Knee with Early and Simultaneous Involvement of the Medial Femoral Condyle and Medial Tibial Plateau

    PubMed Central

    Fujita, Shinya; Arai, Yuji; Honjo, Kuniaki; Nakagawa, Shuji; Kubo, Toshikazu

    2016-01-01

    Spontaneous osteonecrosis of the knee (SPONK) usually involves a single condyle, most often the medial femoral condyle (MFC). Involvement of the medial tibial plateau (MTP) is less common, occurring in about 2% of knees with SPONK. Early onset SPONK on the ipsilateral side of the medial compartment is very rare, with, to our knowledge, only four cases reported to date. We describe a very rare case of SPONK with early simultaneous development in the MFC and MTP. Serial plain radiographs and magnetic resonance imaging showed that SPONK in both condyles followed a similar progressive course. The pathological findings in these lesions were similar to those observed in subchondral insufficiency fractures. PMID:27242941

  10. Parametric study of orthopedic insole of valgus foot on partial foot amputation.

    PubMed

    Guo, Jun-Chao; Wang, Li-Zhen; Chen, Wei; Du, Cheng-Fei; Mo, Zhong-Jun; Fan, Yu-Bo

    2016-01-01

    Orthopedic insole was important for partial foot amputation (PFA) to achieve foot balance and avoid foot deformity. The inapposite insole orthosis was thought to be one of the risk factors of reamputation for foot valgus patient, but biomechanical effects of internal tissues on valgus foot had not been clearly addressed. In this study, plantar pressure on heel and metatarsal regions of PFA was measured using F-Scan. The three-dimensional finite element (FE) model of partial foot evaluated different medial wedge angles (MWAs) (0.0°-10.0°) of orthopedic insole on valgus foot. The effect of orthopedic insole on the internal bone stress, the medial ligament tension of ankle, plantar fascia tension, and plantar pressure was investigated. Plantar pressure on medial heel region was about 2.5 times higher than that of lateral region based on the F-Scan measurements. FE-predicted results showed that the tension of medial ankle ligaments was the lowest, and the plantar pressure was redistributed around the heel, the first metatarsal, and the lateral longitudinal arch regions when MWA of orthopedic insole ranged from 7.5° to 8.0°. The plantar fascias maintained about 3.5% of the total load bearing on foot. However, the internal stresses from foot bones increased. The simulation in this study would provide the suggestion of guiding optimal design of orthopedic insole and therapeutic planning to pedorthist. PMID:26291149

  11. A study of the biological behavior of the meniscus as a transplant in the medial compartment of a dog's knee.

    PubMed

    Canham, W; Stanish, W

    1986-01-01

    A surgical procedure was developed such that a meniscus could be reimplanted in the medial compartment of canine knees. The medial meniscus was removed and reimplanted in one group of seven animals, removed and reimplanted with a glutaraldehyde-preserved bioprosthesis in a second group of five animals, and removed and replaced by an allograft meniscus preserved 2 to 3 weeks in tissue culture in a final group of ten animals. All animals were autopsied at 2 months and the knees were examined by gross dissection and histologic study of the joint capsule meniscal interface. Results showed that implantation by the surgical technique was effective and no loose bodies or partial detachments were found in the reimplantation or tissue culture-stored allogenic menisci. Allogenic menisci preserved in glutaraldehyde and termed a bioprosthesis attached to the joint capsule less satisfactorily. There was minimal inflammation of the synovium in any group at 2 months; however, the glutaraldehyde group showed repeated effusions at 1 and 2 weeks. PMID:3096157

  12. Pelvic limb alignment in small breed dogs: a comparison between affected and free subjects from medial patellar luxation.

    PubMed

    Olimpo, Matteo; Piras, Lisa Adele; Peirone, Bruno

    2016-03-31

    Small breed dogs are 12 times more likely to develop medial patellar luxation (MPL) than large breed dogs and breed predisposition has been reported. Many surgical techniques are available for correction of patellar luxation in dogs. However, recent studies reported an 8% incidence of reluxation when traditional techniques are used. The relatively high frequency of major complications and patellar reluxation may be partially caused by inadequate appreciation of the underlying skeletal deformity and subsequent incorrect selection and application of traditional techniques. The aims of this study were to report the normal values of the anatomic and mechanical joint angles of the femur and tibia in small breed dogs and to compare these data to a population of small breed dogs a ected by di erent degrees of MPL. Normal values of the anatomic and mechanical angles of the femur are similar to the ones reported in literature in Pomeranian dogs. Normal values of the anatomic and mechanical angles of the tibia have been described for the rst time. Signi cant di erences were found between normal population and dogs a ected by grade 4 MPL in relation to anatomical Lateral Distal Femoral Angle (aLDFA), mechanical Medial Proximal Tibial Angle (mMPTA), and mechanical Caudal Proximal Tibial Angle (mCaPTA). PMID:26681507

  13. Preserved Self-Awareness following Extensive Bilateral Brain Damage to the Insula, Anterior Cingulate, and Medial Prefrontal Cortices

    PubMed Central

    Khalsa, Sahib S.; Damasio, Antonio; Tranel, Daniel; Landini, Gregory; Williford, Kenneth

    2012-01-01

    It has been proposed that self-awareness (SA), a multifaceted phenomenon central to human consciousness, depends critically on specific brain regions, namely the insular cortex, the anterior cingulate cortex (ACC), and the medial prefrontal cortex (mPFC). Such a proposal predicts that damage to these regions should disrupt or even abolish SA. We tested this prediction in a rare neurological patient with extensive bilateral brain damage encompassing the insula, ACC, mPFC, and the medial temporal lobes. In spite of severe amnesia, which partially affected his “autobiographical self”, the patient's SA remained fundamentally intact. His Core SA, including basic self-recognition and sense of self-agency, was preserved. His Extended SA and Introspective SA were also largely intact, as he has a stable self-concept and intact higher-order metacognitive abilities. The results suggest that the insular cortex, ACC and mPFC are not required for most aspects of SA. Our findings are compatible with the hypothesis that SA is likely to emerge from more distributed interactions among brain networks including those in the brainstem, thalamus, and posteromedial cortices. PMID:22927899

  14. Contralateral breast dose from partial breast brachytherapy.

    PubMed

    Robinson, R Cole; Nelson, Christopher L; Bloom, Elizabeth S; Kisling, Kelly D; Mason, Bryan E; Fisher, Gary D; Kirsner, Steven M

    2015-01-01

    The purpose of this study was to determine the dose to the contralateral breast during accelerated partial breast irradiation (APBI) and to compare it to external beam-published values. Thermoluminescent dosimeter (TLD) packets were used to measure the dose to the most medial aspect of the contralateral breast during APBI simulation, daily quality assurance (QA), and treatment. All patients in this study were treated with a single-entry, multicatheter device for 10 fractions to a total dose of 34 Gy. A mark was placed on the patient's skin on the medial aspect of the opposite breast. Three TLD packets were taped to this mark during the pretreatment simulation. Simulations consisted of an AP and Lateral scout and a limited axial scan encompassing the lumpectomy cavity (miniscan), if rotation was a concern. After the simulation the TLD packets were removed and the patients were moved to the high-dose-rate (HDR) vault where three new TLD packets were taped onto the patients at the skin mark. Treatment was administered with a Nucletron HDR afterloader using Iridium-192 as the treatment source. Post-treatment, TLDs were read (along with the simulation and QA TLD and a set of standards exposed to a known dose of 6 MV photons). Measurements indicate an average total dose to the contralateral breast of 70 cGy for outer quadrant implants and 181 cGy for inner quadrant implants. Compared to external beam breast tangents, these results point to less dose being delivered to the contralateral breast when using APBI. PMID:26699549

  15. Familial discoid medial meniscus tear in three members of a family: a case report and review of literature.

    PubMed

    Ahmed Ali, Raheel; McKay, Scott

    2014-01-01

    Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins. Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears. Case Presentation. Physically active brothers presented with progressively worsening knee pain. MRI revealed medial meniscus tears in both brothers. The family history of medial meniscus tears in their mother and the discoid medial meniscus injuries found on arthroscopy suggested evidence for familial discoid medial meniscus tears. Conclusions. Discoid medial meniscus tears within a family have not been previously reported. Two cases of families with discoid lateral meniscus tears have been reported. Discoid medial meniscus is rare relative to the discoid lateral meniscus and predisposes children to symptomatic tears. PMID:25548700

  16. Familial Discoid Medial Meniscus Tear in Three Members of a Family: A Case Report and Review of Literature

    PubMed Central

    Ahmed Ali, Raheel; McKay, Scott

    2014-01-01

    Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins. Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears. Case Presentation. Physically active brothers presented with progressively worsening knee pain. MRI revealed medial meniscus tears in both brothers. The family history of medial meniscus tears in their mother and the discoid medial meniscus injuries found on arthroscopy suggested evidence for familial discoid medial meniscus tears. Conclusions. Discoid medial meniscus tears within a family have not been previously reported. Two cases of families with discoid lateral meniscus tears have been reported. Discoid medial meniscus is rare relative to the discoid lateral meniscus and predisposes children to symptomatic tears. PMID:25548700

  17. IMPAIRED CATEGORY FLUENCY IN MEDIAL TEMPORAL LOBE AMNESIA: THE ROLE OF EPISODIC MEMORY

    PubMed Central

    Greenberg, Daniel L.; Keane, Margaret M.; Ryan, Lee; Verfaellie, Mieke

    2009-01-01

    Memory tasks are often classified as semantic or episodic, but recent research shows that these types of memory are highly interactive. Category fluency, for example, is generally considered to reflect retrieval from semantic memory, but behavioral evidence suggests that episodic memory is also involved: Participants frequently draw on autobiographical experiences while generating exemplars of certain categories. Neuroimaging studies accordingly have reported increased medial temporal lobe (MTL) activation during exemplar generation. Studies of fluency in MTL amnesics have yielded mixed results but were not designed to determine the precise contributions of episodic memory. We addressed this issue by asking MTL amnesics and controls to generate exemplars of three types of categories. One type tended to elicit autobiographical and spatial retrieval strategies (AS). Another type elicited strategies that were autobiographical but nonspatial (AN). The third type elicited neither autobiographical nor spatial strategies (N). Amnesic patients and control participants generated exemplars for 8 categories of each type. Patients were impaired on all category types but were more impaired on AS and AN categories. After covarying for phonemic fluency (total FAS score), the N category impairment was not significant, but the impairment on AS and AN categories remained. The same results were obtained for patients with lesions restricted to the MTL and those with more extensive lesions. We conclude that patients’ episodic memory impairment hindered their performance on this putatively semantic task. This interaction between episodic and semantic memory might partially account for fluency deficits seen in aging, mild cognitive impairment, and Alzheimer’s disease. PMID:19726648

  18. Consecutive exotropia: why does it happen, and can medial rectus advancement correct it?

    PubMed Central

    Leon, Bhambi Gesite-de; Demer, Joseph L.

    2014-01-01

    Purpose To investigate whether consecutive exotropia following medial rectus muscle recession is associated with muscle slippage and to assess the effectiveness of treating the condition with medial rectus advancement. Methods The records of patients with consecutive exotropia after medial rectus recession were reviewed to determine medial rectus muscle insertion location at the time of advancement surgery. Measurements before and after medial rectus advancement were compared. Success was defined as alignment within 10Δ of orthotropia. The dose effect of medial rectus advancement was determined by nonlinear regression. Results A total of 20 patients were included. The mean age (± standard deviation) at time of surgery was 19 ± 19 years (range, 1.1–65.4). The mean preoperative exotropia was 28Δ ± 16Δ (range, 12Δ–60Δ). Medial rectus slippage of 2.5 ± 1.7 mm (range, 1.0–5.0 mm) was found in 14 patients (36%) who had previously undergone medial rectus recession. Surgery corrected about 4Δ of exotropia per mm total medial rectus advancement. Although 95% of patients were aligned successfully immediately after surgery, averaging 2Δ ± 4Δ esotropia, there was significant late exodrift, averaging 17Δ at final follow-up. At final follow-up, 1.6 ± 1.8 (range, 0.10–6.2) years after surgery, 50% of patients maintained alignment within 10Δ of orthotropia (mean, 3Δ ± 4Δ exotropia); the rest experienced recurrent exotropia of 25Δ ± 8Δ. Conclusions Medial rectus slippage is common in consecutive exotropia. Medial rectus advancement effectively treated consecutive exotropia, whether or not there was muscle slippage. It is however, associated with late exodrift; hence patients should be warned about potential for further XT recurrence. PMID:25454022

  19. 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

  20. [Facilitation of memory consolidation induced by electrical stimulation of the medial septal nucleus in BALB/c mice (author's transl)].

    PubMed

    Galey, D; Jeantet, Y; Destrade, C; Jaffard, R

    1982-05-01

    Sinusoidal (100Hz) electrical stimulation was applied at a weak intensity (7.5microA peak to peak) to the medial septal nucleus after partial acquisition of an appetitive operant conditioning task in a Skinner box. Analysis of performance recorded 24 hrs later during a retention session shows that (i) implantation alone impaired performance; (ii) electrical stimulation applied 30 sec. after the end of the acquisition session improves retention; this facilitatory effect disappears when the treatment is delayed 15 min. Furthermore spectral analysis of hippocampal EEG showed that there was no significant modification of theta rhythms. These results are discussed in relation to studies in the literature which demonstrate that RSA (rhythmical slow activity) is associated with memory-storage processes and our own hypothesis which underlines the importance of activation of septo-hippocampal cholinergic neurons in the early stages of these mnemonic processes.U PMID:6809247

  1. Twisted partially pure spinors

    NASA Astrophysics Data System (ADS)

    Herrera, Rafael; Tellez, Ivan

    2016-08-01

    Motivated by the relationship between orthogonal complex structures and pure spinors, we define twisted partially pure spinors in order to characterize spinorially subspaces of Euclidean space endowed with a complex structure.

  2. Partial knee replacement - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series To use the sharing features on ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  3. Partial knee replacement

    MedlinePlus

    Most people recover quickly and have much less pain than they did before surgery. People who have a partial knee replacement recover faster than those who have a total knee replacement. Many people are able to walk ...

  4. Angioleiomyoma of the Plantar-Medial Arch: A Case Report

    PubMed Central

    Gilheany, Mark

    2016-01-01

    An angioleiomyoma is a benign soft tissue tumour that arises from smooth muscle layer of blood vessels. The true aetiology of these masses is largely unknown and quite often may not be associated with pain. This paper illustrates the occurrence of an angioleiomyoma in the medial arch of the foot, a previously unreported location. Significant delay occurred in the patient being referred for specialist consultation, after attending numerous general practitioners for management. This highlighted the need for ongoing publication for case reports of this nature. The patient underwent excision with no recurrence of the lesion reported at 12 months. Often masses of this type may be left alone. However, when symptomatic simple excision will suffice where no other surrounding complication exists and where the mass is well encapsulated in the sub cutaneous area.

  5. Galanin neurons in the medial preoptic area govern parental behaviour.

    PubMed

    Wu, Zheng; Autry, Anita E; Bergan, Joseph F; Watabe-Uchida, Mitsuko; Dulac, Catherine G

    2014-05-15

    Mice display robust, stereotyped behaviours towards pups: virgin males typically attack pups, whereas virgin females and sexually experienced males and females display parental care. Here we show that virgin males genetically impaired in vomeronasal sensing do not attack pups and are parental. Furthermore, we uncover a subset of galanin-expressing neurons in the medial preoptic area (MPOA) that are specifically activated during male and female parenting, and a different subpopulation that is activated during mating. Genetic ablation of MPOA galanin neurons results in marked impairment of parental responses in males and females and affects male mating. Optogenetic activation of these neurons in virgin males suppresses inter-male and pup-directed aggression and induces pup grooming. Thus, MPOA galanin neurons emerge as an essential regulatory node of male and female parenting behaviour and other social responses. These results provide an entry point to a circuit-level dissection of parental behaviour and its modulation by social experience. PMID:24828191

  6. The Vascularized Medial Femoral Corticoperiosteal Flap for Thumb Reconstruction

    PubMed Central

    Amin, Kavit; Darhouse, Nagham; Sivakumar, Bran; Floyd, David

    2015-01-01

    Summary: We present an interesting method of shaping a vascularized medial femoral condyle (MFC) flap into a “neophalanx” for phalangeal reconstruction. Our patient presented with limited strength and function secondary to fracture nonunion of the proximal phalanx of the dominant thumb. Following excision of the pseudarthrosis, an MFC corticoperiosteal flap was harvested, sculpted into a prism shape and inset. The superomedial genicular pedicle was anastomosed to the princeps pollicis artery and a cephalic tributary. On follow-up, new bone growth was seen on radiographs and the patient had substantially improved function, with full metacarpophalangeal extension, a Kapandji score of 9, and a markedly reduced Disabilities of the Arm, Shoulder and Hand score of 2.68. The MFC flap is useful for reconstruction of bony defects, with minimal donor morbidity. This versatile vascularized flap can be crafted to requisite shapes and is useful for small defects in the hand, including phalangeal reconstruction. PMID:26495205

  7. The Medial Temporal Lobe Supports Conceptual Implicit Memory

    PubMed Central

    Wang, Wei-Chun; Lazzara, Michele M.; Ranganath, Charan; Knight, Robert T.; Yonelinas, Andrew P.

    2010-01-01

    Summary The medial temporal lobe (MTL) is generally thought to be critical for explicit, but not implicit, memory. Here, we demonstrate that the perirhinal cortex (PRc), within the MTL, plays a role in conceptually-driven implicit memory. Amnesic patients with MTL lesions that converged on the left PRc exhibited deficits on two conceptual implicit tasks (i.e., exemplar generation and semantic decision). A separate functional magnetic resonance imaging (fMRI) study in healthy subjects indicated that PRc activation during encoding of words was predictive of subsequent exemplar generation. Moreover, across subjects, the magnitude of the fMRI and behavioral conceptual priming effects were directly related. Additionally, the PRc region implicated in the fMRI study was the same region of maximal lesion overlap in the patients with impaired conceptual priming. These patient and imaging results converge to suggest that the PRc plays a critical role in conceptual implicit memory, and possibly conceptual processing in general. PMID:21144998

  8. Medial prefrontal cortex predicts internally driven strategy shifts

    PubMed Central

    Schuck, Nicolas W.; Gaschler, Robert; Wenke, Dorit; Heinzle, Jakob; Frensch, Peter A.; Haynes, John-Dylan; Reverberi, Carlo

    2015-01-01

    Summary Many daily behaviors require us to actively focus on the current task and ignore all other distractions. Yet, ignoring everything else might hinder the ability to discover new ways to achieve the same goal. Here, we studied the neural mechanisms that support the spontaneous change to better strategies while an established strategy is executed. Multivariate neuroimaging analysis showed that before the spontaneous change to an alternative strategy, medial prefrontal cortex (MPFC) encoded information that was irrelevant for the current strategy but necessary for the later strategy. Importantly, this neural effect was related to future behavioral changes: information encoding in MPFC was changed only in participants who eventually switched their strategy and started before the actual strategy change. This allowed us to predict spontaneous strategy shifts ahead of time. These findings suggest that MPFC might internally simulate alternative strategies and sheds new light on the organization of PFC. PMID:25819613

  9. PARTIAL TORUS INSTABILITY

    SciTech Connect

    Olmedo, Oscar; Zhang Jie

    2010-07-20

    Flux ropes are now generally accepted to be the magnetic configuration of coronal mass ejections (CMEs), which may be formed prior to or during solar eruptions. In this study, we model the flux rope as a current-carrying partial torus loop with its two footpoints anchored in the photosphere, and investigate its stability in the context of the torus instability (TI). Previous studies on TI have focused on the configuration of a circular torus and revealed the existence of a critical decay index of the overlying constraining magnetic field. Our study reveals that the critical index is a function of the fractional number of the partial torus, defined by the ratio between the arc length of the partial torus above the photosphere and the circumference of a circular torus of equal radius. We refer to this finding as the partial torus instability (PTI). It is found that a partial torus with a smaller fractional number has a smaller critical index, thus requiring a more gradually decreasing magnetic field to stabilize the flux rope. On the other hand, a partial torus with a larger fractional number has a larger critical index. In the limit of a circular torus when the fractional number approaches 1, the critical index goes to a maximum value. We demonstrate that the PTI helps us to understand the confinement, growth, and eventual eruption of a flux-rope CME.

  10. Dopaminergic projections to the medial preoptic area of postpartum rats

    PubMed Central

    Miller, Stephanie M.; Lonstein, Joseph S.

    2010-01-01

    Dopamine receptor activity in the rodent medial preoptic area (mPOA) is crucial for the display of maternal behaviors, as well as numerous other physiological and behavioral functions. However, the origin of dopaminergic input to the mPOA has not been identified through neuroanatomical tracing. To accomplish this, the retrograde tracer Fluorogold was iontophoretically applied to the mPOA of postpartum laboratory rats, and dual-label immunocytochemistry for Fluorogold and tyrosine hydroxylase later performed to identify dopaminergic cells of the forebrain and midbrain projecting to the mPOA. Results indicate that the number of dopaminergic cells projecting to the mPOA is moderate (~90 cells to one hemisphere), and that these cells have an unexpectedly wide distribution. Even so, more than half of the dual-labeled cells were found in what has been considered extensions of the A10 dopamine group (particularly the ventrocaudal posterior hypothalamus and adjacent medial supramammillary nucleus), or in the A10 cells of the ventral tegmental area. The rostral hypothalamus and surrounding region also contained numerous dual-labeled cells, with the greatest number found within the mPOA itself (including in the AVPV and PVpo). Notably, dual-labeled cells were rare in the zona incerta (A13), a site previously suggested to provide dopaminergic input to the mPOA. This study is the first to use anatomical tracing to detail the dopaminergic projections to the mPOA in the laboratory rat, and indicates that much of this projection originates more caudally than previously suggested. PMID:19409227

  11. Multidimensional assessment of functional outcomes of medialization thyroplasty.

    PubMed

    Uloza, Virgilijus; Pribuisiene, Ruta; Saferis, Viktoras

    2005-08-01

    Medialization thyroplasty (MT) is the most widely used laryngeal framework phonosurgical procedure for managing glottic incompetence secondary to unilateral vocal fold paralysis (UVFP). The aim of the study was to evaluate the functional outcomes of MT in 32 UVFP patients, comparing multidimensional perceptual and instrumental measures of voice before and after surgery, and to evaluate how close to normal that postoperative voice measure became. Video laryngostroboscopy (VLS), auditory perceptive evaluation of voice, the patients' self-evaluation of hoarseness on the Visual Analogue Scale (VAS) and calculation of the Voice Handicap Index (VHI), analysis of objective acoustic voice parameters, quantitative assessment of phonetograms and measurement of maximum phonation time were conducted. Vocal function was evaluated before the surgery and for the period from 1 month to 3 years (Mo 1.0 month; Me 2.0 months) after MT. VLS confirmed remarkable medialization of the paralyzed vocal fold. As a consequence, hoarseness and breathiness were found to be significantly decreased after MT. Pitch and intensity range and phonetogram area were significantly increased. A significant decrease of jitter, shimmer and normalized noise energy reflected improvement of the stability of acoustic signal and a more efficient pattern of phonation. Thus, the perceptual and acoustic voice parameters studied showed statistically significant differences (P < 0.001) between preoperative and postoperative voices, and these objective measurements of voice changes provided accurate and documentary evidence of the results of surgical treatment. A high degree of patient satisfaction with the MT was confirmed by a significant decrease of VHI and hoarseness on VAS. Thus, results of the present investigation confirm the functionality and effectiveness of MT in patient voice rehabilitation with UVFP. However, the means of acoustic voice parameters measured in the study did not reach normal limits

  12. Medialized Versus Lateralized Center of Rotation in Reverse Shoulder Arthroplasty.

    PubMed

    Streit, Jonathan J; Shishani, Yousef; Gobezie, Reuben

    2015-12-01

    Reverse shoulder arthroplasty may be performed using components that medialize or lateralize the center of rotation. The purpose of this prospective study was to directly compare 2 reverse shoulder arthroplasty designs. Two treatment groups and 1 control group were identified. Group I comprised 9 patients using a medialized Grammont-style (GRM) prosthesis with a neck-shaft angle of 155°. Group II comprised 9 patients using a lateralized (LAT) prosthesis with a neck-shaft angle of 135°. Pre- and postoperative assessment of range of motion, American Shoulder and Elbow Surgeons score, and visual analog scale pain score were performed. Radiographic measurements of lateral humeral offset and acromiohumeral distance were compared. The GRM prosthesis achieved greater forward flexion (143.9° vs 115.6°; P=.05), whereas the LAT achieved greater external rotation (35.0° vs 28.3°; P=.07). The lateral humeral offset was greater for the LAT prosthesis compared with the GRM prosthesis, but this distance was not significantly different from that found in the control group. The acromiohumeral distance was significantly greater in the GRM prosthesis group compared with both the LAT and the control groups. The results of this study confirm that different reverse shoulder arthroplasty designs produce radiographically different anatomy. Whereas the GRM prosthesis significantly alters the anatomy of the shoulder, the LAT design can preserve some anatomic relationships found in the normal shoulder. The clinical outcomes indicate that this may have an effect on range of motion, with traditional designs achieving greater forward flexion and lateralized designs achieving greater external rotation. PMID:26652330

  13. 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…

  14. Supinated forearm is correlated with the onset of medial epicondylitis in professional slalom water-skiers

    PubMed Central

    Rosa, Donato; Di Donato, Sigismondo Luca; Balato, Giovanni; D’Addona, Alessio; Schonauer, Fabrizio

    2016-01-01

    Summary Background prolonged and laborious activities involving wrists and forearms has been long associated with the onset of epicondylitis. Slalom water-skiing can be included in this category. The purpose of the study is to analyse the correlation between the pronated or supinated position of forearms during water-skiing practice and the presence respectively of lateral and medial epicondylitis. Methods sixty-six pro and semi-pro slalom water-skiers were enrolled in the study. A questionnaire was submitted to each athlete. Diagnosis of lateral or medial epicondylitis was made through anamnesis and clinical exam by an expert orthopaedic surgeon. Chi-squared were performed for categorical variables, and Mann-Whitney U test for continuous ones. Results from 116 upper limbs examined, we observed 15 (12.9%) cases of lateral epicondylitis, 30 (25.9%) cases of medial epicondylitis, 10 (8.6%) were affected by both lateral and medial epicondylitis. Lateral and medial epicondylitis were associated (95% C.I.=2,489–26,355; P=<0,001) and the supinated position was correlated with medial epicondylitis (95% C.I.=1,529–9,542; P=0.003). Conclusion slalom water-skiing can be considered a high-risk sport for epicondylitis. In slalom water-skiers there is a correlation between development of lateral and medial epicondylitis in the same upper limb. Supinated position of forearms is strongly associated with the diagnosis of medial epicondylitis. PMID:27331043

  15. Non-Hodgkin's lymphoma at the medial clavicular head mimicking Tietze Syndrome.

    PubMed

    Jeon, In-Ho; Jeong, Won-Ju; Yi, Jae-Hyuck; Kim, Hyo-Jin; Park, Il-Hyung

    2012-08-01

    We present a case of Non-Hodgkin's lymphoma involving medial clavicular head, which was initially diagnosed as Tietze syndrome. Non-Hodgkin's lymphoma arising from medial clavicular head is extremely rare, and CT, MRI findings have not been reported. PMID:21140267

  16. Situational Restriction of Elevation in Adduction Relieved by Faden on the Medial Rectus

    PubMed Central

    Muralidhar, R.; Vijayalakshmi, P.; Sujatha, K.; Shetty, Shashikanth; Malay, K.; Rosenberg, Steve

    2016-01-01

    We describe a patient with situational restriction of elevation in adduction in his left eye. Clinical examination pointed to instability of the left medial rectus pulley. This was corrected by Faden on the medial rectus. The importance of this relatively new concept in identifying and treating orbital pulley instability is discussed. PMID:27162460

  17. Anterolateral Versus Medial Plating of Distal Extra-articular Tibia Fractures: A Biomechanical Model.

    PubMed

    Pirolo, Joseph M; Behn, Anthony W; Abrams, Geoffrey D; Bishop, Julius A

    2015-09-01

    Both medial and anterolateral plate applications have been described for the treatment of distal tibia fractures, each with distinct advantages and disadvantages. The objective of this study was to compare the biomechanical properties of medial and anterolateral plating constructs used to stabilize simulated varus and valgus fracture patterns of the distal tibia. In 16 synthetic tibia models, a 45° oblique cut was made to model an Orthopedic Trauma Association type 43-A1.2 distal tibia fracture in either a varus or valgus injury pattern. Each fracture was then reduced and plated with a precontoured medial or anterolateral distal tibia plate. The specimens were biomechanically tested in axial and torsional loading, cyclic axial loading, and load to failure. For the varus fracture pattern, medial plating showed less fracture site displacement and rotation and was stiffer in both axial and torsional loading (P<.05). For the valgus fracture pattern, there was no statistically significant difference between medial and anterolateral plating. There were no significant differences between the 2 constructs for either fracture pattern with respect to ultimate load, displacement, or energy absorption in load to failure testing. When used to stabilize varus fracture patterns, medial plates showed superior biomechanical performance compared with anterolateral plates. In this application, the medial plates functioned in anti-glide mode. For valgus fracture patterns, no biomechanical differences between anterolateral and medial plating were observed. In clinical practice, surgeons should take this biomechanical evidence into account when devising a treatment strategy for fixation of distal tibia fractures. PMID:26375532

  18. Ultrasound-assisted endoscopic partial plantar fascia release.

    PubMed

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure. PMID:24265989

  19. Feasibility of the Medial Temporal lobe Atrophy index (MTAi) and derived methods for measuring atrophy of the medial temporal lobe

    PubMed Central

    Conejo Bayón, Francisco; Maese, Jesús; Fernandez Oliveira, Aníbal; Mesas, Tamara; Herrera de la Llave, Estibaliz; Álvarez Avellón, Tania; Menéndez-González, Manuel

    2014-01-01

    Introduction: The Medial Temporal-lobe Atrophy index (MTAi), 2D-Medial Temporal Atrophy (2D-MTA), yearly rate of MTA (yrRMTA) and yearly rate of relative MTA (yrRMTA) are simple protocols for measuring the relative extent of atrophy in the medial temporal lobe (MTL) in relation to the global brain atrophy. Albeit preliminary studies showed interest of these methods in the diagnosis of Alzheimer’s disease (AD), frontotemporal lobe degeneration (FTLD) and correlation with cognitive impairment in Parkinson’s disease (PD), formal feasibility and validity studies remained pending. As a first step, we aimed to assess the feasibility. Mainly, we aimed to assess the reproducibility of measuring the areas needed to compute these indices. We also aimed to assess the efforts needed to start using these methods correctly. Methods: A series of 290 1.5T-MRI studies from 230 subjects ranging 65–85 years old who had been studied for cognitive impairment were used in this study. Six inexperienced tracers (IT) plus one experienced tracer (ET) traced the three areas needed to compute the indices. Finally, tracers underwent a short survey on their experience learning to compute the MTAi and experience of usage, including items relative to training time needed to understand and apply the MTAi, time to perform a study after training and overall satisfaction. Results: Learning to trace the areas needed to compute the MTAi and derived methods is quick and easy. Results indicate very good intrarater Intraclass Correlation Coefficient (ICC) for the MTAi, good intrarater ICC for the 2D-MTA, yrMTA and yrRMTA and also good interrater ICC for the MTAi, 2D-MTA, yrMTA and yrRMTA. Conclusion: Our data support that MTAi and derived methods (2D-MTA, yrMTA and yrRTMA) have good to very good intrarater and interrater reproducibility and may be easily implemented in clinical practice even if new users have no experience tracing the area of regions of interest. PMID:25414666

  20. 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

  1. Coding Odorant Concentration Through Activation Timing Between the Medial and Lateral Olfactory Bulb

    PubMed Central

    Zhou, Zhishang; Belluscio, Leonardo

    2012-01-01

    SUMMARY In mammals, each olfactory bulb (OB) contains a pair of mirror-symmetric glomerular maps organized to reflect odorant receptor identity. The functional implication of maintaining these symmetric medial-lateral maps within each OB remains unclear. Here, using in vivo multi-electrode recordings to simultaneously detect odorant-induced activity across the entire OB, we reveal a timing difference in the odorant-evoked onset latencies between the medial and lateral halves. Interestingly, the latencies in the medial and lateral OB decreased at different rates as odorant concentration increased, causing the timing difference between them to also diminish. As a result, output neurons in the medial and lateral OB fired with greater synchrony at higher odorant concentrations. Thus, we propose that temporal differences in activity between the medial and lateral OB can dynamically code odorant concentration, which is subsequently decoded in the olfactory cortex through the integration of synchronous action potentials. PMID:23168258

  2. Medial Closing-Wedge Distal Femoral Osteotomy: Fixation With Proximal Tibial Locking Plate.

    PubMed

    Tírico, Luís Eduardo Passarelli; Demange, Marco Kawamura; Bonadio, Marcelo Batista; Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Pécora, José Ricardo

    2015-12-01

    Distal femoral varus osteotomy is a well-established procedure for the treatment of lateral compartment cartilage lesions and degenerative disease, correcting limb alignment and decreasing the progression of the pathology. Surgical techniques can be performed with a lateral opening-wedge or medial closing-wedge correction of the deformity. Fixation methods for lateral opening-wedge osteotomies are widely available, and there are various types of implants that can be used for fixation. However, there are currently only a few options of implants for fixation of a medial closing-wedge osteotomy on the market. This report describes a medial, supracondylar, V-shaped, closing-wedge distal femoral osteotomy using a locked anterolateral proximal tibial locking plate that fits anatomically to the medial side of the distal femur. This is a great option as a stable implant for a medial closing-wedge distal femoral osteotomy. PMID:26870647

  3. 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). PMID:26889348

  4. NUCLEUS REUNIENS OF THE MIDLINE THALAMUS: LINK BETWEEN THE MEDIAL PREFRONTAL CORTEX AND THE HIPPOCAMPUS

    PubMed Central

    Vertes, Robert P.; Hoover, Walter B.; Szigeti-Buck, Klara; Leranth, Csaba

    2016-01-01

    The medial prefrontal cortex and the hippocampus serve well recognized roles in memory processing. The hippocampus projects densely to, and exerts strong excitatory actions on, the medial prefrontal cortex. Interestingly, the medial prefrontal cortex, in rats and other species, has no direct return projections to the hippocampus, and few projections to parahippocampal structures including the entorhinal cortex. It is well established that the nucleus reuniens of the midline thalamus is the major source of thalamic afferents to the hippocampus. Since the medial prefrontal cortex also distributes to nucleus reuniens, we examined medial prefrontal connections with populations of nucleus reuniens neurons projecting to hippocampus. We used a combined anterograde and retrograde tracing procedure at the light and electron microscopic levels. Specifically, we made Phaseolus vulgaris-leuccoagglutinin (PHA-L) injections into the medial prefrontal cortex and Fluorogold injections into the hippocampus (CA1/subiculum) and examined termination patterns of anterogradely PHA-L labeled fibers on retrogradely FG labeled cells of nucleus reuniens. At the light microscopic level, we showed that fibers from the medial prefrontal cortex form multiple putative synaptic contacts with dendrites of hippocampally projecting neurons throughout the extent of nucleus reuniens. At ultrastructural level, we showed that medial prefrontal cortical fibers form asymmetric contacts predominantly with dendritic shafts of hippocampally projecting reuniens cells. These findings indicate that nucleus reuniens represents a critical link between the medial prefrontal cortex and the hippocampus. We discuss the possibility that nucleus reuniens gates the flow of information between the medial prefrontal cortex and hippocampus dependent upon attentive/arousal states of the organism. PMID:17292803

  5. Partial spread OFDM

    NASA Astrophysics Data System (ADS)

    Elghariani, Ali; Zoltowski, Michael D.

    2012-05-01

    In this paper, partial spread OFDM system has been presented and its performance has been studied when different detection techniques are employed, such as minimum mean square error (MMSE), grouped Maximum Likelihood (ML) and approximated integer quadratic programming (IQP) techniques . The performance study also includes applying two different spreading matrices, Hadamard and Vandermonde. Extensive computer simulation have been implemented and important results show that partial spread OFDM system improves the BER performance and the frequency diversity of OFDM compared to both non spread and full spread systems. The results from this paper also show that partial spreading technique combined with suboptimal detector could be a better solution for applications that require low receiver complexity and high information detectability.

  6. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-17

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  7. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  8. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    2001-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  9. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-24

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  10. Oxygen partial pressure sensor

    DOEpatents

    Dees, D.W.

    1994-09-06

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured. 1 fig.