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Sample records for differentiate medial meniscal

  1. 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

  2. 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

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

    PubMed

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

    2011-06-01

    Medial meniscal posterior root avulsion (MMRA) leads to deleterious alteration of medial joint compartment loading profiles and increased risk of medial degenerative changes. Surgical repair restores more normal biomechanics to the knee. Our hypothesis is that MMRA will cause medial meniscal (MM) extrusion and gap formation between the root attachment site and MM. Meniscal root repair will restore the ability of the meniscus to resist extrusion, and reduce gap formation at the defect. Seven fresh frozen human cadaveric knees were dissected and mechanically loaded using a servo-hydraulic load frame (MTS ®) with 0 and 1800 N. The knees were tested under three conditions: native, avulsed, and repaired. Four measurements were obtained: meniscal displacement anteriorly, medially, posteriorly, and gap distance between the root attachment site and MM after transection and repair. The medial displacement of the avulsed MM (3.28 mm) was significantly greater (p < 0.001) than the native knee (1.60mm) and repaired knee (1.46 mm). Gap formation is significantly larger in the avulsed compared to repaired state at 0 (p < 0.02) and 1800N (p < 0.02) and also larger with loading in both avulsed (p < 0.05) and repaired (p < 0.02) conditions. Therefore, MMRA results in MM extrusion from the joint and gap formation between the MM root and the MM. Subsequent surgical repair reduces meniscal displacement and gap formation at the defect. PMID:20684881

  4. 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

  5. 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

  6. Free medial meniscal fragment which mimics the dislocated bucket-handle tear on MRI.

    PubMed

    Türkmen, Faik; Korucu, Ismail Hakkı; Sever, Cem; Demirayak, Mehmet; Goncü, Gani; Toker, Serdar

    2014-01-01

    The bucket-handle meniscal tear is a specific type of meniscal injuries which has specific signs on MRI. An attached fragment displaced away from the meniscus with any type of tear causes bucket-handle tear of the meniscus. Magnetic resonance imaging (MRI) is the most commonly used diagnostic tool for meniscal injuries. We present a case of free medial meniscal fragment which mimics the dislocated bucket-handle tear on MRI. The presence of "fragment within the intercondylar notch sign" and "the absence of the bow tie sign" may be an indication of a free meniscal fragment. This should be considered during diagnosis. PMID:25002980

  7. Displaced Medial and Lateral Bucket Handle Meniscal Tears With Intact ACL and PCL.

    PubMed

    Boody, Barrett S; Omar, Imran M; Hill, James A

    2015-08-01

    Bucket handle lesions are vertical longitudinal tears in the meniscus that may displace centrally into the respective medial or lateral compartment, frequently causing mechanical symptoms, including pain, perceived instability, and mechanical locking. Bucket handle meniscal tears are most commonly from a traumatic etiology and are frequently found with concomitant anterior cruciate ligament (ACL) injuries. Multiple imaging signs and associations have been described for the diagnosis of bucket handle meniscus tears, including coronal truncation, absent bow tie sign, double posterior cruciate ligament (PCL), double ACL, displacement of the bucket handle fragment, and disproportionate posterior horn signs. Among meniscal pathology encountered on magnetic resonance imaging or during arthroscopy, bucket handle meniscal tears are infrequent occurrences. Furthermore, the occurrence of displaced medial and lateral bucket handle tears found on imaging and during arthroscopy is very uncommon and is only sparsely reported in the literature. When displaced medial and lateral bucket handle meniscal segments are visualized within the intercondylar notch along with the ACL and PCL, the radiologic findings are referred to as the "quadruple cruciate" sign or the "Jack and Jill lesion." Of the few case reports described in the literature, only one noted displaced medial and lateral bucket handle meniscus tears with an intact ACL and PCL. The current case report outlines a similar rare case of the quadruple cruciate sign: displaced medial and lateral bucket handle meniscal tears located within the intercondylar notch and an intact ACL and PCL. PMID:26270763

  8. 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

  9. Bilateral atraumatic medial meniscal tears in a 17-year-old rower.

    PubMed

    Taylor, Taryn Lise; Frankovich, Renata; Rumball, Jane

    2009-01-01

    Meniscal injury produces disability in a large portion of the population, and sports injuries are a common cause. Atraumatic meniscal tears may occur after repetitive low-energy loading. Rowing is a highly technical sport and very demanding on an athlete's body. There are numerous reports on patellofemoral and iliotibial band friction syndrome in rowers but there is an extremely low incidence of meniscal tears reported in these athletes. This is a unique case report of a young adolescent athlete who suffered bilateral medical meniscal tears during sporting activity. Rowing is a low impact sport making this an unusual occurrence, especially in a young individual. This case report highlights the importance of considering all training activities when trying to isolate the mechanism of injury in an athlete. PMID:21686387

  10. ‘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

  11. Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis

    PubMed Central

    Yu, De-Gang; Nie, Shao-Bo; Liu, Feng-Xiang; Wu, Chuan-Long; Tian, Bo; Wang, Wen-Gang; Wang, Xiao-Qing; Zhu, Zhen-An; Mao, Yuan-Qing

    2015-01-01

    Background: The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA). However, the characteristics of subchondral bone alterations remain unresolved. The present study aimed to observe the dynamic alterations in the microarchitecture, mineralization, and mechanical properties of subchondral bone during the progression of OA. Methods: A medial meniscal tear (MMT) operation was performed in 128 adult Sprague Dawley rats to induce OA. At 2, 4, 8, and 12 weeks following the MMT operation, cartilage degeneration was evaluated using toluidine blue O staining, whereas changes in the microarchitecture indices and tissue mineral density (TMD), mineral-to-collagen ratio, and intrinsic mechanical properties of subchondral bone plates (BPs) and trabecular bones (Tbs) were measured using micro-computed tomography scanning, confocal Raman microspectroscopy and nanoindentation testing, respectively. Results: Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction. Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV, trabecular number, connectivity density and trabecular thickness [Tb.Th], and increased trabecular spacing (Tb.Sp) at 2 and 4 weeks) to bone accretion late (increased BV/TV, Tb.Th and thickness of subchondral bone plate, and reduced Tb.Sp at 8 and 12 weeks). The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks. The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction. Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction. The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks. Conclusion: The microarchitecture, mineralization and mechanical properties of

  12. The Relationship between Meniscal Tears and Meniscal Position

    PubMed Central

    Allen, Deborah M.; Li, Ling; Crema, Michel D.; Marra, Monica D.; Guermazi, Ali; Wyman, Brad T.; Le Graverand, Marie-Pierre Hellio; Englund, Martin; Brandt, Kenneth D.; Hunter, David J.

    2010-01-01

    Objective: To investigate how different types of meniscal tears predispose to different patterns of meniscal position in subjects with and without symptomatic knee osteoarthritis (OA). Methods: A cross-sectional analysis of 161 women participating in an observational study to evaluate knee OA progression was performed using baseline MRI data. Meniscal morphologic features were scored in three separate locations. Meniscal position measures were determined for extrusion and proportion of coverage. Analysis was performed using multiple linear regression models treating each tear type as an individual variable with a binary response. Results: Complex tears, cysts and maceration of the medial meniscus were associated with more medial (p=0.0004, p=0.004, p <0.0001, respectively) and anterior extrusion (p =0.03, p=0.03, p<0.0001, respectively) than normal menisci. Horizontal tears of the lateral meniscus had more lateral (p=0.005) and anterior extrusion (p<0.0001) than normal menisci. Anterior and body tears of the medial meniscus were associated with more anterior extrusion (p=0.0006, p=0.01, respectively), whereas meniscal body tears alone had more medial extrusion than normal menisci (p= 0.0002). Meniscal body tears of the lateral meniscus had more lateral extrusion than normal menisci (p=0.01). Conclusion: Anterior horn and meniscal body tears and the more severe macerated and complex tear types predisposed to more medial meniscal extrusion. Laterally, only meniscal body and horizontal tears significantly affected extrusion, potentially reflecting a lower overall prevalence of lateral meniscal tears. These results may have important implications in identifying tear types associated with more meniscal dysfunction, with the ultimate goal of identifying those at greatest risk for knee OA progression. PMID:22870457

  13. Meniscal Ramp Lesions

    PubMed Central

    Chahla, Jorge; Dean, Chase S.; Moatshe, Gilbert; Mitchell, Justin J.; Cram, Tyler R.; Yacuzzi, Carlos; LaPrade, Robert F.

    2016-01-01

    Meniscal ramp lesions are more frequently associated with anterior cruciate ligament (ACL) injuries than previously recognized. Some authors suggest that this entity results from disruption of the meniscotibial ligaments of the posterior horn of the medial meniscus, whereas others support the idea that it is created by a tear of the peripheral attachment of the posterior horn of the medial meniscus. Magnetic resonance imaging (MRI) scans have been reported to have a low sensitivity, and consequently, ramp lesions often go undiagnosed. Therefore, to rule out a ramp lesion, an arthroscopic evaluation with probing of the posterior horn of the medial meniscus should be performed. Several treatment options have been reported, including nonsurgical management, inside-out meniscal repair, or all-inside meniscal repair. In cases of isolated ramp lesions, a standard meniscal repair rehabilitation protocol should be followed. However, when a concomitant ACL reconstruction (ACLR) is performed, the rehabilitation should follow the designated ACLR postoperative protocol. The purpose of this article was to review the current literature regarding meniscal ramp lesions and summarize the pertinent anatomy, biomechanics, diagnostic strategies, recommended treatment options, and postoperative protocol. PMID:27504467

  14. Double Meniscal Ossicle, the First Description: CT and MRI Findings—Different Etiologies

    PubMed Central

    Kumar, Puneeth; Dey, Amit Kumar; Mittal, Kartik; Sharma, Rajaram; Hira, Priya

    2015-01-01

    We present a case of 2 ossicles in the medial meniscus with emphasis on MRI and CT findings. Meniscal ossicle is a rare entity and is quite uncommon on the medial side. By showing the typical signal characteristics and intrameniscal location, MRI can be helpful in distinguishing this from other more clinically significant abnormalities. It should be kept as differential from synovial chondromatosis or sesamoid bones like fabella as management is different for all of these entities. PMID:26788396

  15. Double Meniscal Ossicle, the First Description: CT and MRI Findings-Different Etiologies.

    PubMed

    Kumar, Puneeth; Dey, Amit Kumar; Mittal, Kartik; Sharma, Rajaram; Hira, Priya

    2015-01-01

    We present a case of 2 ossicles in the medial meniscus with emphasis on MRI and CT findings. Meniscal ossicle is a rare entity and is quite uncommon on the medial side. By showing the typical signal characteristics and intrameniscal location, MRI can be helpful in distinguishing this from other more clinically significant abnormalities. It should be kept as differential from synovial chondromatosis or sesamoid bones like fabella as management is different for all of these entities. PMID:26788396

  16. 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.

  17. Amino acid racemization reveals differential protein turnover in osteoarthritic articular and meniscal cartilages

    PubMed Central

    Stabler, Thomas V; Byers, Samuel S; Zura, Robert D; Kraus, Virginia Byers

    2009-01-01

    Introduction Certain amino acids within proteins have been reported to change from the L form to the D form over time. This process is known as racemization and is most likely to occur in long-lived low-turnover tissues such as normal cartilage. We hypothesized that diseased tissue, as found in an osteoarthritic (OA) joint, would have increased turnover reflected by a decrease in the racemized amino acid content. Methods Using high-performance liquid chromatography methods, we quantified the L and D forms of amino acids reported to racemize in vivo on a biological timescale: alanine, aspartate (Asp), asparagine (Asn), glutamate, glutamine, isoleucine, leucine (Leu), and serine (Ser). Furthermore, using a metabolically inactive control material (tooth dentin) and a control material with normal metabolism (normal articular cartilage), we developed an age adjustment in order to make inferences about the state of protein turnover in cartilage and meniscus. Results In the metabolically inactive control material (n = 25, ages 13 to 80 years) and the normal metabolizing control material (n = 19, ages 17 to 83 years), only Asp + Asn (Asx), Ser, and Leu showed a significant change (increase) in racemization with age (P < 0.01). The age-adjusted proportions of racemized to total amino acid (D/D+L expressed as a percentage of the control material) for Asx, Ser, and Leu when compared with the normal articular cartilage control were 97%, 74%, and 73% in OA meniscal cartilage and 97%, 70%, and 78% in OA articular cartilage. We also observed lower amino acid content in OA articular and meniscal cartilages compared with normal articular cartilage as well as a loss of total amino acids with age in the OA meniscal but not the OA articular cartilage. Conclusions These data demonstrate comparable anabolic responses for non-lesioned OA articular cartilage and OA meniscal cartilage but an excess of catabolism over anabolism for the meniscal cartilage. PMID:19267899

  18. Meniscal Repair

    PubMed Central

    Yoon, Kyoung Ho

    2014-01-01

    The meniscus has several important roles, such as transmission of the load, absorption of the shock in the knee joint, acting as a secondary anteroposterior stabilizer of the knee joint, and contributing to proprioception of the knee joint. Degenerative changes of the knee joint develop in the long-term follow-up even after partial meniscectomy. Thus, there has been growing interest in meniscal repair. In addition, with increased understanding of the important roles of the meniscal root and advancement of diagnostic methods, efforts have been made to ensure preservation of the meniscal roots. In this review article, we will discuss operative techniques and clinical outcomes of arthroscopic repair of the meniscus and the meniscal root and postoperative rehabilitation and complications as well. PMID:24944971

  19. Meniscal ossification.

    PubMed

    Mine, Takatomo; Taguchi, Tosihiko; Ihara, Koichiro; Tanaka, Hiroshi; Moriwaki, Tohru; Kawai, Shinya

    2003-02-01

    Meniscal ossicles are rare in the human knee. We present one case. A 57-year-old taxi driver complained of right knee pain and swelling with radiographic findings of a meniscal ossicle. Arthroscopic inspection showed a degenerative and horizontal tear and calcium deposit at the middle and posterior thirds of lateral discoid meniscus. His lateral discoid meniscus, containing the ossicle, was removed. He was asymptomatic at a 3-year follow-up. PMID:12579140

  20. Repair of avascular meniscal injuries using juvenile meniscal fragments: an in vitro organ culture study.

    PubMed

    Dai, Zhu; Li, Kanghua; Chen, Zhiwei; Liao, Ying; Yang, Lezhong; Liu, Chunlei; Ding, Wenjun

    2013-10-01

    We investigated whether the implantation of juvenile allograft and minced meniscal fragments could improve the healing of avascular meniscal injuries, which cannot heal spontaneously. Concentric cylindrical explants were excised from the inner two-thirds of swine medial menisci. The inner cylinder consisted of a "sandwich" structure, with minced juvenile meniscal fragments, juvenile meniscal columns, minced mature meniscal fragments, or mature meniscal columns implanted in the middle. The explants were cultured in vitro for 2, 4, or 6 weeks. Interfacial meniscal repair was assessed by histology, immunohistochemistry, biomechanical testing, and confocal laser scanning microscopy. Histology and confocal microscopy results revealed that tissue repair and cell accumulation at the interface were best at all time points in the juvenile meniscal fragments group, followed by the juvenile columns, minced mature fragments, and mature columns groups, respectively. At 6 weeks, the implantation of juvenile allograft and minced meniscal fragments increased the shear strength, peak force, and energy to failure in the peripheral interface. Picosirius red/polarized light microscopy and immunohistochemistry results showed concurrent expression of type I and II collagen in the interfacial repair tissue. In conclusion, implantation of juvenile allograft and minced meniscal fragments could increase the healing of avascular meniscal injury in vitro. PMID:23813750

  1. Induction of meniscal regeneration in dogs using a novel biomaterial.

    PubMed

    Cook, J L; Tomlinson, J L; Kreeger, J M; Cook, C R

    1999-01-01

    A unique biomaterial, porcine small intestinal submucosa, was used to construct grafts for implantation into surgically created medial meniscal defects in dogs. Five dogs received grafts and two were left untreated as controls. All dogs were evaluated at 4, 8, and 12 weeks by means of lameness scoring, force plate analysis, and ultrasonography. Twelve weeks after implantation the dogs were sacrificed and the replacement tissue was evaluated for gross and histologic appearance, amount, glycosaminoglycan content, and type II collagen immunoreactivity. Four weeks after instrumentation, both groups had lameness scores that were significantly higher than preoperative scores, but at the 8- and 12-week evaluations, scores for the grafted dogs were not different from preoperative values. The ultrasonographic appearance of replacement tissue in grafted defects resembled normal meniscus. In the untreated defects, only unorganized tissue was present. In control dogs, replacement tissue resembled fibrous tissue and cartilage erosions were visible on the medial femoral condyles. In four of the five grafted dogs, replacement tissue was grossly indistinguishable from normal meniscus. The amount of tissue in the defect was significantly greater for the grafted dogs. Histologically, replacement tissue in control dogs was composed of vascularized connective tissue with no evidence of chondroid differentiation. Replacement tissue in grafted dogs closely resembled normal meniscal tissue with respect to chondroid differentiation, collagen content, and zonal architecture. Porcine small intestinal submucosa appeared to have beneficial effects on meniscal regeneration. PMID:10496586

  2. High resolution MRI evaluation of meniscal volume and anthropometric correlations.

    PubMed

    Narvy, Steven J; Asami, Danny K; Solomon, Thomas C; Burke, Wendy S; Colletti, Patrick M; Vangsness, C Thomas

    2015-09-01

    The purpose of this study was to digitally determine meniscal volumes, and compare them with linear and surface area anthropometric measurements to evaluate these measurements for meniscal allograft sizing. Eighteen subjects (10 male and 8 female; mean age 37.5 years) underwent 3.0 T knee magnetic resonance imaging (MRI) of the dominant leg. The following morphometric measurements were evaluated: medial meniscal volume (MMV), lateral meniscal volume (LMV), tibial plateau width (TPW), width of the femoral condyles (WFC), and tibial plateau surface area (TPSA). MMV and LMV were compared to TPW, WFC, and TPSA. Meniscal volume and TPW were correlated to height and body-mass index (BMI) and stratified by gender. Statistical analysis included coefficient of determination (r(2)) between MRI-based MMV, LMV, TPW, TPSA, WFC, height, BMI, and gender. Significance was set at the P = 0.05 level. The mean MMV was 2275 mm(3) and the mean LMV was 2102 mm(3). TPW correlated well with meniscal volumes (r(2) > 0.62). WFC and TPSA correlated with meniscal volumes in the range of 0.40 < r(2) < 0.61. Height, BMI, and gender correlated poorly with total meniscal volume and TPW with values of r(2) < 0.44. Medial and lateral menisci have statistically similar volumes. TPW had the greatest utility for volumetric meniscal sizing. MRI-based TPW can be considered as a statistically accurate measurement for determining meniscal volumes and meniscal size. PMID:26118625

  3. 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

  4. Arthroscopic revisions in failed meniscal surgery.

    PubMed

    Spahn, Gunter

    2003-01-01

    The aim of this study was to classify meniscal tear forms as found in 195 revision arthroscopies. Interval between primary arthroscopy and revision was 7.8+/-5.6 month. All patients were available for control after 1 year. In 174 knees the lesion was located in the medial meniscus and in 21 knees in the lateral meniscus. In the medial meniscus an unstable posterior meniscal horn was seen in 93 knees followed by incomplete horizontal tear and meniscal destruction in 37. Flap tear, circumferential tear, and failed meniscal repair were also seen. In the lateral meniscus destruction of a discoid meniscus, instability near the popliteal hiatus, and various tear forms were seen with nearly equal frequency. Postoperatively Lysholm score increased significantly in both groups. Most meniscal tears, found in revision arthroscopy, are caused by an insufficient primary operation. A diligent analysis of the tear form is absolutely necessary. An adequate radical resection technique to establish a smooth meniscal crest is indispensable. PMID:12904905

  5. Evaluation of three approaches to meniscal release.

    PubMed

    Austin, B; Montgomery, R D; Wright, J; Bellah, J R; Tonks, C

    2007-01-01

    Three approaches to medial meniscal release (MMR) were compared using 48 canine cadaver stifles. The approaches included a caudomedial arthrotomy approach, a blind stab incision based on anatomic landmarks, and an arthroscopic guided approach. The cranial cruciate ligament was intact in all specimens. The time required to perform the meniscal release and joint capsule closure was recorded, as well as completeness and location of the meniscal transection. Damage to the caudal cruciate ligament, femoral cartilage, and medial collateral ligament were recorded. The mini-arthrotomy was 81% successful in accomplishment of MMR with a 4% rate of iatrogenic damage. The blind technique was 56% successful in the accomplishment of MMR with a 4% rate of iatrogenic damage. The arthroscopic guided approach was 62.5% successful in accomplishment of MMR, with a 10% rate of iatrogenic damage. Accomplishment and iatrogenic damage rates were not significantly different among procedures (p > 0.05). Significantly less time was required to perform the blind technique, and significantly greater time was required to perform the arthroscopic guided technique (p > 0.05). Significant differences were not noted among the procedures regarding the ability to accomplish the meniscal release or damage surrounding structures. None of the evaluated approaches for meniscal release resulted in a complete and accurate meniscal release for over 81% of the time. PMID:17546208

  6. Meniscal Root Tear Repair: Why, When and How?

    PubMed Central

    Bonasia, Davide Edoardo; Pellegrino, Pietro; D’Amelio, Andrea; Cottino, Umberto; Rossi, Roberto

    2015-01-01

    The integrity of the meniscal root insertions is fundamental to preserve correct knee kinematics and avoid degenerative changes of the knee. Injuries to the meniscal attachments can lead to meniscal extrusion, decreased contact surface, increased cartilage stress, and ultimately articular degeneration. Recent and well designed studies have clarified the anatomy and biomechanics of the medial and lateral meniscal roots. Although the treatment of meniscal root tears is still controversial, many different techniques have been described for root repair. The goal of this review is to summarize the existing knowledge regarding meniscal root tears, including anatomy, biomechanics and imaging. In addition, the most common surgical techniques, together with the clinical outcomes, are described. PMID:26330993

  7. Arthroscopic Decompression for a Giant Meniscal Cyst.

    PubMed

    Ohishi, Tsuyoshi; Suzuki, Daisuke; Matsuyama, Yukihiro

    2016-01-01

    The authors report the case of a giant medial meniscal cyst in an osteoarthritic knee of an 82-year-old woman that was successfully treated with only arthroscopic cyst decompression. The patient noticed a painful mass on the medial side of the right knee that had been gradually growing for 5 years. Magnetic resonance imaging showed an encapsulated large medial cystic mass measuring 80×65×40 mm that was adjacent to the medial meniscus. An accompanying horizontal tear was also detected in the middle and posterior segments of the meniscus. The medial meniscus was resected up to the capsular attachment to create bidirectional flow between the joint and the cyst with arthroscopic surgery. Magnetic resonance imaging performed 14 months postoperatively showed that the cyst had completely disappeared, and no recurrence was observed during a 2-year follow-up period. An excellent result could be obtained by performing limited meniscectomy to create a channel leading to the meniscal cyst, even though the cyst was large. Among previously reported cases of meniscal cysts, this case is the largest to be treated arthroscopically without open excision. PMID:26726987

  8. Meniscal Root Tears: Identification and Repair.

    PubMed

    Doherty, David B; Lowe, Walter R

    2016-01-01

    Intact menisci are capable of converting the axial load of tibiofemoral contact into hoop stress that protects the knee joint. Total meniscectomy leads to rapid degeneration of the knee. Strong clinical and biomechanical data show meniscal root tears and avulsions are the functional equivalent of total meniscectomy. Lateral root tears commonly occur with knee ligament sprains and tears. Medial root tears are generally more chronic, and can be caused by preexisting knee arthritis. Meniscal root repair is indicated when there is identification of a meniscal root tear in a knee with minimal to no arthritis. Chronic root tears in the setting of osteoarthritis are treated conservatively. Meniscal root tears can acutely occur with cruciate ligament tears, can exaggerate symptoms of instability, and will have negative ramifications on outcomes of anterior cruciate ligament reconstruction if not addressed concomitantly. In this review, we describe the importance of the menisci for knee joint longevity through anatomy and biomechanics, the diagnostic workup, and ultimately a transosseous technique for repair of meniscal root tears and avulsions. PMID:27004274

  9. Meniscal mineralisation in little spotted cats

    PubMed Central

    2013-01-01

    Background The aim of this study was to evaluate the stifle joints of little spotted cats in captivity using radiographic and CT studies. The hypothesis was that these animals would have meniscal mineralisation that could be detectable by imaging studies. Twelve intact little spotted cats (Leopardus tigrinus), 2 females and 10 males, aged from 1.5 to 11.11 years old and weighing 1.9–3.05 kg were studied. These animals, which were living in the Quinzinho de Barros Municipal Zoo, had no symptoms or known disease processes at the time of the study. The plain radiographs and computed tomography (CT) scans of both stifle joints were performed under general anaesthesia. Sequential transverse images were acquired on a spiral scanner. Results No signs of articular disease were observed in any of the animals. Radiographically, the meniscal mineralisation was detected as an oval radiopacity in the cranial compartment on the mediolateral projection, located within the area of the medial meniscus. On craniocaudal projection, the mineralisation was more difficult to visualise. In one of the animals, it was not possible to identify the meniscal mineralisation in either of the stifle joints. Using CT, meniscal mineralisation was best identified in the transverse plane images. Conclusions Meniscal mineralisation appears to be a normal anatomic feature in little spotted cats. PMID:23506083

  10. Low-field Mri and arthroscopy of meniscal lesions in ten dogs with experimentally induced cranial cruciate ligament insufficiency.

    PubMed

    Martig, Sandra; Konar, Martin; Schmökel, Hugo G; Rytz, Ueli; Spreng, David; Scheidegger, Jürg; Höhl, Birgit; Kircher, Patrick R; Boisclair, Julie; Lang, Johann

    2006-01-01

    Little is known about the magnetic resonance imaging (MRI) appearance of canine meniscal lesions. The aim of this study is to describe the MR appearance of meniscal lesions in dogs with experimentally induced cranial cruciate ligament (CCL) deficiency. The pilot study revealed dogs weighing approximately 10 kg to be too small for meniscal evaluation on low-field MRI. In the main study, dogs weighing approximately 35 kg were used. The left CCL was transected and low-field MRI was performed regularly until 13 months post-surgery. Normal menisci were defined as grade 0. Intrameniscal lesions not reaching any surface corresponded to grade 1 if focal and to grade 2 if linear or diffuse. Grade 3 lesions consisted in linear tears penetrating a meniscal surface. Grade 4 lesions included complex signal changes or meniscal distortion. Between 2 and 13 months post-surgery, all dogs developed grade 4 lesions in the medial meniscus. Most of them corresponded to longitudinal or bucket handle tears on arthroscopy and necropsy. Two dogs showed grade 3 lesions reaching the tibial surface of the lateral meniscus on MRI but not in arthroscopy. Such tears are difficult to evaluate arthroscopically; MRI provides more accurate information about the tibial meniscal surface. Grades 1 and 2 lesions could not be differentiated from presumably normal menisci with our imaging technique. An MRI grading system better adapted to canine lesions has yet to be developed. MRI is a helpful tool for the diagnosis of complete tears in the canine meniscus, especially in larger dogs. PMID:17153058

  11. The potential of optical coherence tomography for diagnosing meniscal pathology

    NASA Astrophysics Data System (ADS)

    Hang-Yin Ling, Carrie; Pozzi, Antonio; Thieman, Kelley M.; Tonks, Catherine A.; Guo, Shuguang; Xie, Huikai; Horodyski, MaryBeth

    2010-04-01

    Meniscal tears are often associated with anterior cruciate ligament (ACL) injury and may lead to pain and discomfort in humans. Maximal preservation of meniscal tissue is highly desirable to mitigate the progression of osteoarthritis. Guidelines of which meniscal tears are amenable to repair and what part of damaged tissues should be removed are elusive and lacking consensus. Images of microstructural changes in meniscus would potentially guide the surgeons to manage the meniscal tears better, but the resolution of current diagnostic techniques is limited for this application. In this study, we demonstrated the feasibility of using optical coherence tomography (OCT) for the diagnosis of meniscal pathology. Torn medial menisci were collected from dogs with ACL insufficiency. The torn meniscus was divided into three tissue samples and scanned by OCT and scanning electron microscopy (SEM). OCT and SEM images of torn menisci were compared. Each sample was evaluated for gross and microstructural abnormalities and reduction or loss of birefringence from the OCT images. The abnormalities detected with OCT were described for each type of tear. OCT holds promise in non-destructive and fast assessment of microstructural changes and tissue birefringence of meniscal tears. Future development of intraoperative OCT may help surgeons in the decision making of meniscal treatment.

  12. Differential effects of GDF5 on the medial and lateral rat ventral mesencephalon.

    PubMed

    Clayton, Kevin B; Sullivan, Aideen M

    2007-11-12

    Growth/differentiation factor 5 (GDF5) is a member of the transforming growth factor-beta (TGF-beta) superfamily that has potent neurotrophic and protective effects on dopaminergic neurones and is expressed in the developing rat substantia nigra (the ventral mesencephalon; VM). GDF5 has the potential to be used in the treatment of Parkinson's disease (PD), a neurodegenerative disorder characterised by the selective degeneration of nigrostriatal dopaminergic neurones. One therapy being explored for PD involves transplantation of fetal VM tissue into the striatum in order to replace lost dopaminergic neurones. The majority of transplantation studies have used transplants incorporating the whole VM. The principal location of dopaminergic neurones in the E14 rat VM is in the medial VM. In the present study, the effects of GDF5 on cultures prepared from medial, lateral and whole E14 rat VM tissue were compared. GDF5 treatment increased the number of dopaminergic neurones in whole and lateral, but not in medial, VM cultures, whereas it increased total cell number in medial, but not in whole or lateral, VM cultures. RT-PCR studies showed that the receptors for GDF5 were differentially expressed in E14 VM; the expression of BMPR-IB and Ror2 was low in medial but high in lateral VM tissue. This study suggests that GDF5 increases the number of dopaminergic neurones in whole VM cultures by acting on BMPR-IB and Ror2-expressing cells in the lateral VM. PMID:17935884

  13. Time Interval between Trauma and Arthroscopic Meniscal Repair Has No Influence on Clinical Survival.

    PubMed

    van der Wal, Robert J P; Thomassen, Bregje J W; Swen, Jan-Willem A; van Arkel, Ewoud R A

    2016-07-01

    Arthroscopic meniscal repair is the gold standard for longitudinal peripheral meniscal tears. The time interval between trauma and meniscal repair remains controversial. The aim of this study was to evaluate failure rates and clinical outcome of arthroscopic meniscal repair in relation to chronicity of injury. A total of 238 meniscal repairs were performed in 234 patients. Anterior cruciate ligament (ACL) was reconstructed in almost all ACL-deficient knees (130 out of 133). Time interval between injury and repair was divided into acute (< 2 weeks), subacute (> 2 to < 12 weeks), and chronic (> 12 weeks). Patients completed postal questionnaires to evaluate clinical outcome and failure rates. Study instruments included Lysholm, Knee injury and Osteoarthritis Outcome Score (KOOS), and Tegner scoring systems. At a median follow-up of 41 months (interquartile range [IQR], 34-53 months) 55 medial and 10 lateral meniscal repairs failed (overall failure rate, 27%). There was a significant higher failure rate for medial meniscal repair (p < 0.05) and ACL-deficient knees without ACL reconstruction. Functional outcome scores showed only significant differences on the KOOS subscale "function in daily living" (95% confidence interval, 1.05-15.27, p < 0.05). No significant difference was found for any interval between trauma and repair. The interval between trauma and arthroscopic meniscal repair has no influence on the failure rate. Differences in survival rate of meniscal repair are more dependent on location of the lesion and ACL status, rather than chronicity of injury. PMID:26516071

  14. Effect of Microfracture on Meniscal Tear Healing in a Goat (Capra hircus) Model.

    PubMed

    Howarth, William R; Brochard, Kevin; Campbell, Scot E; Grogan, Brian F

    2016-03-01

    Meniscal injuries are an extremely common cause of knee pain. Meniscal repairs performed with concomitant anterior cruciate ligament reconstruction appear to heal at a higher rate than meniscal repairs performed in isolation. This may be due in part to the release of marrow elements into the knee and the time of meniscal repair. In cases of isolated meniscal repair, some orthopedic surgeons use microfracture to release marrow elements into the joint as an adjunct to enhance meniscal healing. This study evaluated rates of meniscal tear healing with or without the performance of microfracture in a goat (Capra hircus) model. Forty castrated young adult male goats underwent either a horizontal or a longitudinal 1.0-cm meniscal tear with or without microfracture. All procedures were performed open, in a bloodless field. Meniscal tears were created in the peripheral half of the body of the medial meniscus. The goats were euthanized at 6 months, and meniscal tears were analyzed and classified as complete healing, partial healing, or no healing by direct visualization. A probe was used as an aid to evaluate and classify the meniscal tears. Twenty (87%) of 23 goat meniscal tears showed at least partial healing when performed with concomitant microfracture. Only 5 (29%) of 17 menisci showed any healing in goats that did not receive microfracture. This difference in healing rates was statistically significant (P<.001). Fifteen (65%) meniscal tears accomplished with microfracture were completely healed, whereas only 2 (12%) menisci showed complete healing without microfracture (P<.001). The results of this study suggest that the release of bone marrow elements into the knee by microfracture improves meniscal healing rates. [Orthopedics. 2016; 39(2):105-110.]. PMID:26811956

  15. 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

  16. Meniscal injury: II. Management.

    PubMed

    Greis, Patrick E; Holmstrom, Michael C; Bardana, Davide D; Burks, Robert T

    2002-01-01

    Meniscal repair is a viable alternative to resection in many clinical situations. Repair techniques traditionally have utilized a variety of suture methods, including inside-out and outside-in techniques. Bioabsorbable implants permit all-inside arthroscopic repairs. The success of meniscal repair depends on appropriate meniscal bed preparation and surgical technique and is also influenced by biologic factors such as tear rim width and associated ligamentous injury. Successful repair in >80% of cases has been reported in conjunction with anterior cruciate ligament reconstruction. Success rates are lower for isolated repairs. Complications related to repair include neurologic injury, postoperative loss of motion, recurrence of the tear, and infection. Meniscal allograft transplantation may provide a treatment option when meniscus salvage is not possible or when a previous total meniscectomy has been done. PMID:12041939

  17. Cellular repopulation of deep-frozen meniscal autografts: an experimental study in the dog.

    PubMed

    Arnoczky, S P; DiCarlo, E F; O'Brien, S J; Warren, R F

    1992-01-01

    This study evaluated the cellular repopulation of deep-frozen meniscal autografts. Medial menisci of adult dogs were excised, deep-frozen in liquid nitrogen (-196 degrees C) for 10 min, and orthotopically reimplanted into the joint. Deep-freezing was found to effectively kill all the cells within the meniscus as determined by the absence of Na(2)35SO4 incorporation. Following orthotopic replacement within the knee joint, menisci were repopulated with cells that seemed to originate from the adjacent synovium. These cells migrated over the surface of the meniscus and began to invade the deeper layers of the tissue. However, even after 6 months, the central core of the meniscus remained acellular. While the new cells appeared to modulate into cells that are similar in appearance to meniscal fibrochondrocytes, the exact phenotypic expression of these newly differentiated cells has yet to be determined. Histological alterations, as manifested by a loss of normal orientation of the collagen architecture of the superficial layers of the meniscus; was evident at 6 months and suggests that a remodeling phenomenon may be associated with the cellular repopulation. While biomaterial studies have not been carried out on these specimens, the morphologic alterations observed in the collagen orientation would suggest a possible alteration in the material properties of the repopulated meniscus. The clinical implication of this study is that the structural remodeling associated with the cellular repopulation of deep-frozen meniscal allografts may make the transplanted meniscus more susceptible to injury. PMID:1466700

  18. External Perturbation of the Trunk in Standing Humans Differentially Activates Components of the Medial Back Muscles

    PubMed Central

    Moseley, G Lorimer; Hodges, Paul W; Gandevia, S C

    2003-01-01

    During voluntary arm movements, the medial back muscles are differentially active. It is not known whether differential activity also occurs when the trunk is perturbed unpredictably, when the earliest responses are initiated by short-latency spinal mechanisms rather than voluntary commands. To assess this, in unpredictable and self-initiated conditions, a weight was dropped into a bucket that was held by the standing subject (n= 7). EMG activity was recorded from the deep (Deep MF), superficial (Sup MF) and lateral (Lat MF) lumbar multifidus, the thoracic erector spinae (ES) and the biceps brachii. With unpredictable perturbations, EMG activity was first noted in the biceps brachii, then the thoracic ES, followed synchronously in the components of the multifidus. During self-initiated perturbations, background EMG in the Deep MF increased two- to threefold, and the latency of the loading response decreased in six out of the seven subjects. In Sup MF and Lat MF, this increase in background EMG was not observed, and the latency of the loading response was increased. Short-latency reflex mechanisms do not cause differential action of the medial back muscles when the trunk is loaded. However, during voluntary tasks the central nervous system exerts a ‘tuned response’, which involves discrete activity in the deep and superficial components of the medial lumbar muscles in a way that varies according to the biomechanical action of the muscle component. PMID:12562944

  19. Advances in Meniscal Tissue Engineering

    PubMed Central

    Longo, Umile Giuseppe; Loppini, Mattia; Forriol, Francisco; Romeo, Giovanni; Maffulli, Nicola; Denaro, Vincenzo

    2012-01-01

    Meniscal tears are the most common knee injuries and have a poor ability of healing. In the last few decades, several techniques have been increasingly used to optimize meniscal healing. Current research efforts of tissue engineering try to combine cell-based therapy, growth factors, gene therapy, and reabsorbable scaffolds to promote healing of meniscal defects. Preliminary studies did not allow to draw definitive conclusions on the use of these techniques for routine management of meniscal lesions. We performed a review of the available literature on current techniques of tissue engineering for the management of meniscal tears. PMID:25098366

  20. Arthroscopic Repair of Posterior Meniscal Root Tears

    PubMed Central

    Matheny, Lauren; Moulton, Samuel G.; Dean, Chase S.; LaPrade, Robert F.

    2016-01-01

    Objectives: The purpose of this study was to compare subjective clinical outcomes in patients requiring arthroscopic transtibial pullout repair for posterior meniscus root tears of the medial and lateral menisci. We hypothesized that improvement in function and activity level would be similar among patients undergoing lateral and medial meniscal root repairs. Methods: This study was IRB approved. All patients who underwent posterior meniscal root repair by a single orthopaedic surgeon were included in this study. Detailed operative data were documented at surgery. Patients completed a subjective questionnaire, including Lysholm score, Tegner activity scale, WOMAC, SF-12 and patient satisfaction with outcome, which were collected preoperatively and at a minimum of two years postoperatively. Failure was defined as any patient who underwent revision meniscal root repair or partial meniscectomy following the index surgery. Results: There were 50 patients (16 females, 34 males) with a mean age of 37.8 years (range, 16.6-65.7) and a mean BMI of 27.3 (range, 20.5-49.2) included in this study. Fifteen patients underwent lateral meniscus root repair and 35 patients underwent medial meniscus root repair. Three patients who underwent lateral meniscus root repair required revision meniscus root repair surgery, while no patients who underwent medial meniscus root repair required revision surgery (p=0.26). There was a significant difference in preoperative and postoperative Lysholm score (53 vs. 78) (p<0.001), Tegner activity scale (2.0 vs. 4.0) (p=0.03), SF-12 physical component subscale (38 vs. 50) (p=0.001) and WOMAC (36 vs. 8) (p<0.001) for the total population. Median patient satisfaction with outcome was 9 (range, 1-10). There was no significant difference in mean age between lateral and medial root repair groups (32 vs. 40) (p=0.12) or gender (p=0.19). There was no significant difference in gender between lateral and medial root repair groups (p=0.95). There was a

  1. MRI imaging of displaced meniscal tears: Report of a case highlighting new potential pitfalls of the MRI signs

    PubMed Central

    Prasad, Abhishek; Brar, Rahat; Rana, Shaleen

    2014-01-01

    Magnetic resonance imaging (MRI) has been found to be an excellent imaging tool for meniscal injuries. Various MRI signs have been described to detect displaced meniscal injuries, specifically the bucket-handle tears. Although these signs are quite helpful in diagnosing meniscal tears, various pitfalls have also been reported for these signs. Double anterior cruciate ligament (ACL) sign refers to presence of a linear hypointense soft tissue anterior to the ACL, which represented the flipped bucket-handle tear of the meniscus. Disproportional posterior horn and flipped meniscus signs represent asymmetrically thickened horns of the menisci due to overlying displaced meniscal fragments. We report a case wherein MRI of the knee showed tear and displacement of the medial patellofemoral ligament (MPFL) and vastus medialis complex, medial collateral ligament (MCL), and posterior cruciate ligament (PCL) mimicking these signs. To our knowledge, internally displaced MPFL and MCLs have not been described as mimics for displaced meniscal fragments. PMID:25114394

  2. Characterization of Meniscal Pathology Using Molecular and Proteomic Analyses.

    PubMed

    Roller, Brandon L; Monibi, Farrah; Stoker, Aaron M; Bal, B Sonny; Stannard, James P; Cook, James L

    2015-12-01

    The meniscus is a complex tissue and is integral to knee joint health and function. Although the meniscus has been studied for years, a relatively large amount of basic science data on meniscal health and disease are unavailable. Genomic and proteomic analyses of meniscal pathology could greatly improve our understanding of etiopathogenesis and the progression of meniscal disease, yet these analyses are lacking in the current literature. Therefore, the objective of this study was to use microarray and proteomic analyses to compare aged-normal and pathologic meniscal tissues. Meniscal tissue was collected from the knees of five patient groups (n = 3/group). Cohorts included patients undergoing meniscectomy with or without articular cartilage pathology, patients undergoing total knee arthroplasty with mild or moderate-severe osteoarthritis, and aged-normal controls from organ donors. Tissue sections were collected from the white/white and white/red zones of posterior medial menisci. Expression levels were compared between pathologic and control menisci to identify genes of interest (at least a ×1.5 fold change in expression levels between two or more groups) using microarray analysis. Proteomics analysis was performed using mass spectrometry to identify proteins of interest (those with possible trends identified between the aged-normal and pathologic groups). The microarray identified 157 genes of interest. Genes were categorized into the following subgroups: (1) synthesis, (2) vascularity, (3) degradation and antidegradation, and (4) signaling pathways. Mass spectrometry identified 173 proteins of interest. Proteins were further divided into the following categories: (1) extracellular matrix (ECM) proteins; (2) proteins associated with vascularity; (3) degradation and antidegradation proteins; (4) cytoskeleton proteins; (5) glycolysis pathway proteins; and (6) signaling proteins. These data provide novel molecular and biochemical information for the

  3. BIORESORBABLE POLYMERIC MENISCAL PROSTHESIS: STUDY IN RABBITS

    PubMed Central

    Cardoso, Tulio Pereira; de Rezende Duek, Eliana Aparecida; Amatuzzi, Marco Martins; Caetano, Edie Benedito

    2015-01-01

    Objective: To induce growth of a neomeniscus into the pores of a prosthesis in order to protect the knee joint cartilage. Methods: 70 knees of 35 New Zealand rabbits were operated. The rabbits were five to seven months old, weighed 2 to 3.8 kilograms, and 22 were male and 13 were female. Each animal underwent medial meniscectomy in both knees during a single operation. A bioabsorbable polymeric meniscal prosthesis composed of 70% polydioxanone and 30% L-lactic acid polymer was implanted in one side. The animals were sacrificed after different postoperative time intervals. The femoral condyles and neomeniscus were subjected to histological analysis. Histograms were used to measure the degradation and absorption of the prosthesis, the growth of meniscal tissue in the prosthesis and the degree of degradation of the femoral condyle joint cartilage. Results: The data obtained showed that tissue growth histologically resembling a normal meniscus occurred, with gradual absorption of the prosthesis, and the percentages of chondrocytes on the control side and prosthesis side. Conclusion: Tissue growth into the prosthesis pores that histologically resembled the normal rabbit meniscus was observed. The joint cartilage of the femoral condyles on the prosthesis side presented greater numbers of chondrocytes in all its layers. PMID:27022549

  4. Arthroscopic meniscal repair and needle aspiration for meniscal tear with meniscal cyst.

    PubMed

    Lu, Ko-Hsiu

    2006-12-01

    Treatment of patients with meniscal cysts of the meniscus usually requires surgery. Arthroscopic partial meniscectomy of the involved torn meniscus with intra-articular cyst drainage has become the accepted intervention. However, if the meniscal tear is peripheral, a lot of healthy meniscal tissue is needlessly sacrificed with subtotal meniscectomy. Moreover, the meniscal cyst is not a true cyst, so it may be treated more conservatively after the underlying disease has been corrected. We report a case of a meniscal cyst arising from the anterior segment of the lateral torn meniscus that was arthroscopically repaired with an outside-in technique. With the use of a 19-gauge long needle to penetrate the peripheral rim inframeniscally, a nonabsorbable No. 3-0 nylon suture was passed into the joint and brought out suprameniscally to loop the meniscal fragment. The second suture was passed and was used to secure the meniscal rim and fragment by the same means approximately 8 to 10 mm from the first one. Then the cyst was aspirated. A good result was obtained, and no recurrence of the cyst or mechanical problems occurred after a follow-up of 14 months. PMID:17157745

  5. The effect of axial and abaxial release on meniscal displacement in the dog.

    PubMed

    Kennedy, S C; Dunning, D; Bischoff, M G; Kuriashkin, I V; Pijanowski, G J; Schaeffer, D J

    2005-01-01

    The meniscal release (MR) is used to minimize meniscal pathology after Tibial Plateau Leveling Osteotomy (TPLO) surgery. The purposes of this study were: (i) to describe meniscal orientation in a unaltered cadaveric canine stifle, a cruciate deficient stifle, TPLO repaired stifle with and without the MR using magnetic resonance imaging; (ii) to determine if the abaxial release is equivalent to the axial release in its ability to affect caudal pole displacement in a TPLO repaired stifle and (iii) to evaluate with MRI the effect of MR on the femorotibiol articular cartilage contact area in a TPLO repaired stifle. Briefly, cadaver limbs were placed into a jig designed to mimic a weight-bearing stance at 140 degrees and 90 degrees at the stifle. The limbs were sequentially evaluated from the unaltered state; after cranial cruciate ligament transection; after TPLO stabilization; and finally after a meniscal release. No significant difference was found between the intrameniscal area (IMA) of the abaxial and axial meniscal releases although there was an increase in the IMA after the meniscal release compared to the IMA in the normal, cranial cruciate ligament deficient stifle, and TPLO stabilized stifle. In the abaxial release, a meniscal remnant remained in situ and provided a space effect between the femur and the tibial plateau. This is in contrast to the axial meniscal release, where the entire caudal pole of the medial meniscus relocated caudolaterally and consequently permitted more direct femorotibial contact. Overall, however, there was evidence of caudal pole compression of the medial meniscus throughout the MRI series which was ameliorated by either of the MR procedures. PMID:16594391

  6. The arthroscopic anatomy of symptomatic meniscal lesions.

    PubMed

    Dandy, D J

    1990-07-01

    The anatomy of 1000 symptomatic meniscus lesions is described and related to the age of the patients. All symptomatic lesions found during the study period were treated by arthroscopic surgery. Meniscal lesions were commoner in the right knee (56.5%) and 81% of the patients were men. Of the medial meniscus tears, 75% were vertical and 23% horizontal. Vertical tears of the medial meniscus occurred most often in the fourth decade and horizontal tears in the fifth. There were 22% type I, 37% type II and 31% type III vertical tears; 62% of type I tears and 23% of type II tears had locked fragments. Superior flaps were six times more common than inferior flaps. Of all medial meniscus fragments, 6% were inverted; 51% of these were flaps and the rest ruptured bucket-handle fragments. Of the lateral meniscus lesions 54% were vertical tears, 15% oblique, 15% myxoid, 4% were inverted and 5% were lesions of discoid menisci. The commonest pattern of tear in the lateral compartment (27%) was a vertical tear involving half the length and half the width of the meniscus. PMID:2380218

  7. Meniscal repair using the Polysorb Meniscal Stapler XLS.

    PubMed

    Oberlander, Michael A; Chisar, Michael A

    2005-09-01

    We present our technique of repair of meniscal tears in 11 patients using a newly designed stapler, the Polysorb Meniscal Stapler XLS (USS Sports Medicine, Norwalk, CT), to increase the effectiveness and ease of repair of tears in the vascular zone while limiting potential complications. The low-profile stapler comes with a reloadable pistol grip device and a disposable straight or 15 degrees upcurved shaft with a single preloaded 10-mm staple. Standard anteromedial and anterolateral portals were used, along with a superomedial portal for inflow. The portal was enlarged slightly to facilitate introduction of the cannula or the stapler directly into the knee. The nose of the stapler was applied to the superior surface of the inner edge of the meniscal tear. The sharp points on the tip of the nose were used to manipulate the inner edge and coapt the tear site. Firm pressure was applied to the meniscal tissue, and the nose of the stapler was embedded in the inner edge of the meniscus no more than 2 to 3 mm from the tear (as measured along the meniscal surface). The handle was pulled slowly as the staple engaged the meniscal tissue. This step was repeated every 3 to 4 mm to ensure ideal tear stabilization. PMID:16171646

  8. Analysis of Zfhx1a mutant mice reveals palatal shelf contact independent medial edge epithelial differentiation during palate fusion

    PubMed Central

    Jin, Jiu-Zhen; Li, Qun; Higashi, Yujiro; Darling, Douglas S.; Ding, Jixiang

    2008-01-01

    Cleft palate is a common birth defect that involves disruptions in multiple developmental steps such as growth, differentiation, elevation and fusion. Medial edge epithelial (MEE) differentiation is essential for palate fusion. An important question is that the MEE differentiation during fusion is induced by palate shelf contact or is programmed intrinsically by the palate shelf itself. Here, we report that the loss of Zfhx1a function in mice leads to a cleft palate phenotype that is mainly due to a delay in palate elevation. Zfhx1a encodes a transcription regulatory protein that modulates several signaling pathways including those activated by members of the TGF-β superfamily. Loss of Zfhx1a function in mice leads to a complete cleft palate with 100% penetrance. Zfhx1a mutant palatal shelves display normal cell differentiation and proliferation and are able to fuse in an in vitro culture system. The only defect detected was a 24–48 hour delay in palatal shelf elevation. Using the Zfhx1a mutant as a model, we studied the relationship between medial edge epithelial differentiation and palate contact/adhesion. We found that down regulation of Jag2 expression in the medial edge epithelial cells, a key differentiation event establishing palate fusion competence is independent of palate contact/adhesion. Moreover, the expression of several key factors essential for fusion, such as TGF-β3 and MMP13, are also down regulated at stage E16.5 in a contact independent manner, suggesting that differentiation of the medial edge epithelium is largely programmed through an intrinsic mechanism within the palate shelf. PMID:18470539

  9. Meniscal injuries in basketball players.

    PubMed

    Zedde, Pietro; Mela, Federico; Del Prete, Fabio; Masia, Francesco; Manunta, Andrea F

    2014-01-01

    Basketball is a highly competitive sport in which the knee joint is constantly subject to physical stresses. Basketball-related traumatic injuries are the result of specific technical movements. Even though basketball is not considered a contact sport, injuries in basketball players are due both to athletes' handling of the ball and to their intense physical interaction during games. Nowadays, traumatic meniscal injuries are constantly on the increase, especially in young athletes, and they are generally the result of compressive forces together with knee flexion rotation. Recognition of the great importance of meniscal biomechanics and of the functional role of the meniscus has resulted in the adoption of an increasingly preserving approach, also in the light of the effects, in terms of articular degeneration, of removing meniscal tissue. Even though recent decades have seen considerable developments in arthroscopic meniscectomy techniques, geared at preserving as much meniscal tissue as possible, basketball players undergoing this treatment often present, in the long run, clinical symptomatology severe enough to compromise their participation in competitive sport. Hence the treatment of meniscal injuries in athletes has become more and more preserving in recent years, through recourse to surgical techniques such as meniscal repair, biological replacement implantation and donor meniscus implantation, which allow pain relief, return to competitive activities and stable long-term results, slowing down arthritic progression. Therefore, considering the increasing number of meniscal injuries in basketball players, which can jeopardize their sporting careers, great importance is now attached to early diagnosis and to the correct choice of meniscal injury treatment in these athletes. PMID:25750909

  10. Stable Meniscal Tears Left In Situ at the Time of Arthroscopic Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    PubMed

    Rothermich, Marcus A; Cohen, Jared A; Wright, Rick

    2016-04-01

    Meniscal tears can be incidentally encountered at the time of anterior cruciate ligament (ACL) reconstruction. In these cases, the surgeon has several treatment options that include benign neglect, debridement, trephination, and repair. The authors performed a systematic review of the literature studying the various treatment options for meniscal tears discovered at the time of ACL reconstruction. This systematic review included eight articles that had relevant data regarding benign neglect compared with debridement, trephination, or repair of incidentally encountered meniscal tears. Combined data from these studies resulted in a total of 646 meniscal tears treated with benign neglect with follow-up information available. Importantly, there were differences in reoperation rates between medial and lateral meniscal tears left in situ. However, stable medial and lateral meniscal tears treated with benign neglect did not have different subjective or objective outcomes than those treated with surgical intervention. This systematic review concludes that when stable meniscal tears are encountered at the time of arthroscopic ACL reconstruction, benign neglect can be used for a successful outcome. PMID:25927355

  11. Factors Predicting Meniscal Allograft Transplantation Failure

    PubMed Central

    Parkinson, Ben; Smith, Nicholas; Asplin, Laura; Thompson, Peter; Spalding, Tim

    2016-01-01

    Background: Meniscal allograft transplantation (MAT) is performed to improve symptoms and function in patients with a meniscal-deficient compartment of the knee. Numerous studies have shown a consistent improvement in patient-reported outcomes, but high failure rates have been reported by some studies. The typical patients undergoing MAT often have multiple other pathologies that require treatment at the time of surgery. The factors that predict failure of a meniscal allograft within this complex patient group are not clearly defined. Purpose: To determine predictors of MAT failure in a large series to refine the indications for surgery and better inform future patients. Study Design: Cohort study; Level of evidence, 3. Methods: All patients undergoing MAT at a single institution between May 2005 and May 2014 with a minimum of 1-year follow-up were prospectively evaluated and included in this study. Failure was defined as removal of the allograft, revision transplantation, or conversion to a joint replacement. Patients were grouped according to the articular cartilage status at the time of the index surgery: group 1, intact or partial-thickness chondral loss; group 2, full-thickness chondral loss 1 condyle; and group 3, full-thickness chondral loss both condyles. The Cox proportional hazards model was used to determine significant predictors of failure, independently of other factors. Kaplan-Meier survival curves were produced for overall survival and significant predictors of failure in the Cox proportional hazards model. Results: There were 125 consecutive MATs performed, with 1 patient lost to follow-up. The median follow-up was 3 years (range, 1-10 years). The 5-year graft survival for the entire cohort was 82% (group 1, 97%; group 2, 82%; group 3, 62%). The probability of failure in group 1 was 85% lower (95% CI, 13%-97%) than in group 3 at any time. The probability of failure with lateral allografts was 76% lower (95% CI, 16%-89%) than medial allografts at

  12. Catecholamine receptors differentially mediate impulsive choice in the medial prefrontal and orbitofrontal cortex.

    PubMed

    Pardey, Margery C; Kumar, Natasha N; Goodchild, Ann K; Cornish, Jennifer L

    2013-02-01

    Impulsivity is characteristic of several mental health disorders and is largely mediated by the prefrontal cortex subregions: the medial prefrontal cortex (mPFC) and the orbitofrontal cortex (OFC). Dopamine (DA) and norepinephrine (NE) are known to modulate activity of the prefrontal cortex, however their direct role in impulsive choice is not known. The aim of the present study was to investigate the effect of microinjecting DA or NE compounds in the mPFC or OFC on impulsive choice as measured by a delayed reinforcement (DR) task in male Wistar Kyoto rats. Following training in the DR task, rats were pretreated with DA D(1) and D(2) receptor antagonists (SCH23390 3 μg/side, raclopride 3 or 6 μg/side) or NE α(1) and α(2) receptor agonists (phenylephrine 0.1 or 0.3 μg/side, guanfacine 1 or 3 μg/side, respectively) into the mPFC or OFC and the effect on impulsive behavior was assessed. Pretreatment with raclopride into the mPFC or OFC significantly increased impulsive choice, however only pretreatment with SCH23390 into the mPFC, and not the OFC, significantly increased impulsive choice. Pretreatment with the NE receptor agonists had no effect on impulsive choice. This study suggests that DA receptors, but not NE receptors, differentially mediate impulsive choice in sub-regions of the prefrontal cortex. PMID:23135240

  13. Differentiation of human pluripotent stem cells into Medial Ganglionic Eminence vs. Caudal Ganglionic Eminence cells.

    PubMed

    Ahn, Sandra; Kim, Tae-Gon; Kim, Kwang-Soo; Chung, Sangmi

    2016-05-15

    Human pluripotent stem cells (PSCs) represent an opportunity to study human development in vitro, to model diseases in a dish, to screen drugs as well as to provide an unlimited and ethically unimpeded source of therapeutic cells. Cortical GABAergic interneurons, which are generated from Medial Ganglionic Eminence (MGE) cells and Caudal Ganglionic Eminence (CGE) cells during embryonic development, regulate cortical neural networks by providing inhibitory inputs. Their malfunction, resulting in failure to intricately regulate neural circuit balance, has been implicated in brain diseases, such as schizophrenia, autism and epilepsy. In this study, using combinatorial and temporal modulation of developmentally relevant dorsoventral and rostrocaudal signaling pathways, we efficiently generated MGE cells vs. CGE cells from human PSCs, which predominantly generate Parvalbumin-expressing or Somatostatin-expressing interneurons vs. Calretinin-expressing interneurons, respectively. Efficient generation of specific differentiated progenies of hPSCs as shown in this study will be a pivotal step to realize the full potential of hPSCs for regenerative medicine, developmental studies, disease modeling, bioassay, and drug screening. PMID:26364591

  14. Left and right 6-hydroxydopamine lesions of the medial prefrontal cortex differentially affect voluntary ethanol consumption.

    PubMed

    Nielsen, D M; Crosley, K J; Keller, R W; Glick, S D; Carlson, J N

    1999-03-27

    Dopaminergic projections to the medial prefrontal cortex (mPFC) were unilaterally lesioned with 6-hydroxydopamine (6-OHDA) to examine how dopamine (DA) asymmetry in the mPFC influences voluntary ethanol consumption. Differences in nucleus accumbens (NAS) DA neurotransmission have been related to individual differences in locomotor activity and in the rewarding efficacy of ethanol. Therefore, differences in locomotor activity were used to further characterize the effects of unilateral mPFC 6-OHDA lesions on ethanol consumption. Male Long Evans rats were assessed for high versus low levels of spontaneous locomotor activity. DA terminals in the left or right mPFC were unilaterally lesioned with 6-OHDA, resulting in an average DA depletion of 54% and 50%, respectively. After a minimum seven-day recovery period, preference for a 10% ethanol solution vs. water was determined in a 24-h 2-bottle home-cage free-choice paradigm. Left mPFC 6-OHDA lesions increased and right lesions decreased ethanol consumption. These differential effects of left and right lesions were primarily attributable to rats exhibiting low locomotor activity prior to surgery. The present data suggest that right greater than left cortical DA asymmetry in combination with low endogenous NAS DA (predicted by low locomotor activity levels) may increase the vulnerability to abuse ethanol. PMID:10095012

  15. Diagnostic accuracy of magnetic resonance imaging for meniscal tears in dogs affected with naturally occuring cranial cruciate ligament rupture.

    PubMed

    Blond, Laurent; Thrall, Donald E; Roe, Simon C; Chailleux, Nadege; Robertson, Ian D

    2008-01-01

    A stifle magnetic resonance (MR) imaging protocol was developed based on the appearance of the cruciate ligaments and menisci in normal dogs. Proton density images were subjectively considered to have the highest likelihood of detecting a meniscal lesion. Following this initial evaluation, the accuracy of high-field MR imaging to detect meniscal tears in dogs was evaluated in 11 dogs suffering from naturally occurring cranial cruciate ligament rupture. Dogs underwent MR imaging of the affected stifle before surgery. MR imaging and surgical findings were assessed independently, and then compared. Five tears of the medial meniscus were correctly diagnosed with MR imaging and 19 normal menisci were accurately characterized as such, based on MR images. In one medial meniscus, changes consistent with meniscal degeneration were seen on MR images but this was not seen at surgery. With regard to the lateral meniscus, one false positive diagnosis of a tear was made and this likely represented a normal variation. One other lateral meniscus had changes consistent with meniscal degeneration but, as with the similar lesion seen in the medial meniscus, this was not confirmed surgically. The global sensitivity of MR imaging for the diagnosis of a meniscal tear was 100% and the specificity was 94%. High-field MR imaging is a reliable method to diagnose meniscal tears preoperatively and this may be useful in selecting the surgical approach to clinically abnormal joints and may decrease the need for arthrotomy. PMID:18833948

  16. Differential Effects of Stress on Microglial Cell Activation in Male and Female Medial Prefrontal Cortex

    PubMed Central

    Bollinger, Justin L.; Bergeon Burns, Christine M.; Wellman, Cara L.

    2016-01-01

    Susceptibility to stress-linked psychological disorders, including post-traumatic stress disorder and depression, differs between men and women. Dysfunction of medial prefrontal cortex (mPFC) has been implicated in many of these disorders. Chronic stress affects mPFC in a sex-dependent manner, differentially remodeling dendritic morphology and disrupting prefrontally mediated behaviors in males and females. Chronic restraint stress induces microglial activation, reflected in altered microglial morphology and immune factor expression, in mPFC in male rats. Unstressed females exhibit increased microglial ramification in several brain regions compared to males, suggesting both heightened basal activation and a potential for sex-dependent effects of stress on microglial activation. Therefore, we assessed microglial density and ramification in the prelimbic region of mPFC, and immune-associated genes in dorsal mPFC in male and female rats following acute or chronic restraint stress. Control rats were left unstressed. On the final day of restraint, brains were collected for either qPCR or visualization of microglia using Iba-1 immunohistochemistry. Microglia in mPFC were classified as ramified, primed, reactive, or amoeboid, and counted stereologically. Expression of microglia-associated genes (MHCII, CD40, IL6, CX3CL1, and CX3CR1) was also assessed using qPCR. Unstressed females showed a greater proportion of primed to ramified microglia relative to males, alongside heightened CX3CL1-CX3CR1 expression. Acute and chronic restraint stress reduced the proportion of primed to ramified microglia and microglial CD40 expression in females, but did not significantly alter microglial activation in males. This sex difference in microglial activation could contribute to the differential effects of stress on mPFC structure and function in males versus females. PMID:26441134

  17. Differential effects of stress on microglial cell activation in male and female medial prefrontal cortex.

    PubMed

    Bollinger, Justin L; Bergeon Burns, Christine M; Wellman, Cara L

    2016-02-01

    Susceptibility to stress-linked psychological disorders, including post-traumatic stress disorder and depression, differs between men and women. Dysfunction of medial prefrontal cortex (mPFC) has been implicated in many of these disorders. Chronic stress affects mPFC in a sex-dependent manner, differentially remodeling dendritic morphology and disrupting prefrontally mediated behaviors in males and females. Chronic restraint stress induces microglial activation, reflected in altered microglial morphology and immune factor expression, in mPFC in male rats. Unstressed females exhibit increased microglial ramification in several brain regions compared to males, suggesting both heightened basal activation and a potential for sex-dependent effects of stress on microglial activation. Therefore, we assessed microglial density and ramification in the prelimbic region of mPFC, and immune-associated genes in dorsal mPFC in male and female rats following acute or chronic restraint stress. Control rats were left unstressed. On the final day of restraint, brains were collected for either qPCR or visualization of microglia using Iba-1 immunohistochemistry. Microglia in mPFC were classified as ramified, primed, reactive, or amoeboid, and counted stereologically. Expression of microglia-associated genes (MHCII, CD40, IL6, CX3CL1, and CX3CR1) was also assessed using qPCR. Unstressed females showed a greater proportion of primed to ramified microglia relative to males, alongside heightened CX3CL1-CX3CR1 expression. Acute and chronic restraint stress reduced the proportion of primed to ramified microglia and microglial CD40 expression in females, but did not significantly alter microglial activation in males. This sex difference in microglial activation could contribute to the differential effects of stress on mPFC structure and function in males versus females. PMID:26441134

  18. Diagnosing Snapping Sartorius Tendon Secondary to a Meniscal Cyst Using Dynamic Ultrasound Avoids Incorrect Surgical Procedure

    PubMed Central

    Douglas, Robert J.; Martin, David

    2013-01-01

    We describe a case of painful snapping in the medial aspect of the knee of a 40-year-old man, following a knee hyperflexion injury. Dynamic real-time ultrasonography determined that the snapping was due to the distal tendon of sartorius passing over a medial meniscal cyst. The patient subsequently underwent arthroscopic decompression of the cyst instead of an inappropriate hamstring tendon harvest procedure, with complete resolution of symptoms. PMID:24198995

  19. Differential roles of medial prefrontal subregions in the regulation of drug seeking.

    PubMed

    Moorman, David E; James, Morgan H; McGlinchey, Ellen M; Aston-Jones, Gary

    2015-12-01

    The prefrontal cortex plays an important role in shaping cognition and behavior. Many studies have shown that medial prefrontal cortex (mPFC) plays a key role in seeking, extinction, and reinstatement of cocaine seeking in rodent models of relapse. Subregions of mPFC appear to play distinct roles in these behaviors, such that the prelimbic cortex (PL) is proposed to drive cocaine seeking and the infralimbic cortex (IL) is proposed to suppress cocaine seeking after extinction. This dichotomy of mPFC function may be a general attribute, as similar dorsal-ventral distinctions exist for expression vs. extinction of fear conditioning. However, other results indicate that the role of mPFC neurons in reward processing is more complex than a simple PL-seek vs. IL-extinguish dichotomy. Both PL and IL have been shown to drive and inhibit drug seeking (and other types of behaviors) depending on a range of factors including the behavioral context, the drug-history of the animal, and the type of drug investigated. This heterogeneity of findings may reflect multiple subcircuits within each of these PFC areas supporting unique functions. It may also reflect the fact that the mPFC plays a multifaceted role in shaping cognition and behavior, including those overlapping with cocaine seeking and extinction. Here we discuss research leading to the hypothesis that dorsal and ventral mPFC differentially control drug seeking and extinction. We also present recent results calling the absolute nature of a PL vs. IL dichotomy into question. Finally, we consider alternate functions for mPFC that correspond less to response execution and inhibition and instead incorporate the complex cognitive behavior for which the mPFC is broadly appreciated. PMID:25529632

  20. Axial alignment of the lower limb in patients with isolated meniscal tear.

    PubMed

    Habata, T; Ishimura, M; Ohgushi, H; Tamai, S; Fujisawa, Y

    1998-01-01

    Meniscal tears do not always result from trauma. To elucidate other factors responsible for meniscal tears, we evaluated the axial alignment of the lower limb in 385 patients (385 menisci) with isolated meniscal tear who were examined between 1972 and 1994. The patients were aged 50 years or less and had no ulceration or defect of articular cartilage of the knee when examined arthroscopically. Of the 385 menisci, 90 were lateral complete discoid; 110, lateral incomplete discoid; 68, lateral semilunar; and 117, medial semilunar. Patients in each of these four groups were divided into four subgroups according to sex and whether there was an obvious history of trauma. The so-called Mikulicz's mechanical axis of the affected side was utilized to evaluate the alignment. The axial alignment of the lower limb was normal in the patients with isolated tears of lateral complete discoid meniscus, lateral incomplete discoid, or lateral semilunar. It appeared that the axial alignment of the lower limb did not have a relationship with the occurrence of these tears. Patients with isolated tears of medial semilunar meniscus without obvious trauma, showed varus deformity of the knee. This deformity appeared to be closely related to the presence of medial meniscal tear. PMID:9654560

  1. Meniscal Transplantation and its Effect on Osteoarthritis Risk

    PubMed Central

    Smith, N. A.; Achten, J.; Parsons, N.; Wright, D.; Parkinson, B.; Thompson, P.; Hutchinson, C. E.; Spalding, T.; Costa, M. L.

    2015-01-01

    Objectives Subtotal or total meniscectomy in the medial or lateral compartment of the knee results in a high risk of future osteoarthritis. Meniscal allograft transplantation has been performed for over thirty years with the scientifically plausible hypothesis that it functions in a similar way to a native meniscus. It is thought that a meniscal allograft transplant has a chondroprotective effect, reducing symptoms and the long-term risk of osteoarthritis. However, this hypothesis has never been tested in a high-quality study on human participants. This study aims to address this shortfall by performing a pilot randomised controlled trial within the context of a comprehensive cohort study design. Methods Patients will be randomised to receive either meniscal transplant or a non-operative, personalised knee therapy program. MRIs will be performed every four months for one year. The primary endpoint is the mean change in cartilage volume in the weight-bearing area of the knee at one year post intervention. Secondary outcome measures include the mean change in cartilage thickness, T2 maps, patient-reported outcome measures, health economics assessment and complications. Results This study is expected to report its findings in 2016. Cite this article: Bone Joint Res 2015;4:93–8 PMID:26036203

  2. 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

  3. Differential efferent projections of the anterior, posteroventral, and posterodorsal subdivisions of the medial amygdala in mice

    PubMed Central

    Pardo-Bellver, Cecília; Cádiz-Moretti, Bernardita; Novejarque, Amparo; Martínez-García, Fernando; Lanuza, Enrique

    2012-01-01

    The medial amygdaloid nucleus (Me) is a key structure in the control of sociosexual behavior in mice. It receives direct projections from the main and accessory olfactory bulbs (AOB), as well as an important hormonal input. To better understand its behavioral role, in this work we investigate the structures receiving information from the Me, by analysing the efferent projections from its anterior (MeA), posterodorsal (MePD) and posteroventral (MePV) subdivisions, using anterograde neuronal tracing with biotinylated and tetrametylrhodamine-conjugated dextranamines. The Me is strongly interconnected with the rest of the chemosensory amygdala, but shows only moderate projections to the central nucleus and light projections to the associative nuclei of the basolateral amygdaloid complex. In addition, the MeA originates a strong feedback projection to the deep mitral cell layer of the AOB, whereas the MePV projects to its granule cell layer. The Me (especially the MeA) has also moderate projections to different olfactory structures, including the piriform cortex (Pir). The densest outputs of the Me target the bed nucleus of the stria terminalis (BST) and the hypothalamus. The MeA and MePV project to key structures of the circuit involved in the defensive response against predators (medial posterointermediate BST, anterior hypothalamic area, dorsomedial aspect of the ventromedial hypothalamic nucleus), although less dense projections also innervate reproductive-related nuclei. In contrast, the MePD projects mainly to structures that control reproductive behaviors [medial posteromedial BST, medial preoptic nucleus, and ventrolateral aspect of the ventromedial hypothalamic nucleus], although less dense projections to defensive-related nuclei also exist. These results confirm and extend previous results in other rodents and suggest that the medial amygdala is anatomically and functionally compartmentalized. PMID:22933993

  4. Physicians’ accuracy and interrator reliability for the diagnosis of unstable meniscal tears in patients having osteoarthritis of the knee

    PubMed Central

    Dervin, Geoffrey F.; Stiell, Ian G.; Wells, George A.; Rody, Kelly; Grabowski, Jenny

    2001-01-01

    Objective To determine clinicians’ accuracy and reliability for the clinical diagnosis of unstable meniscus tears in patients with symptomatic osteoarthritis of the knee. Design A prospective cohort study. Setting A single tertiary care centre. Patients One hundred and fifty-two patients with symptomatic osteoarthritis of the knee refractory to conservative medical treatment were selected for prospective evaluation of arthroscopic débridement. Intervention Arthroscopic débridement of the knee, including meniscal tear and chondral flap resection, without abrasion arthroplasty. Outcome measures A standardized assessment protocol was administered to each patient by 2 independent observers. Arthroscopic determination of unstable meniscal tears was recorded by 1 observer who reviewed a video recording and was blinded to preoperative data. Those variables that had the highest interobserver agreement and the strongest association with meniscal tear by univariate methods were entered into logistic regression to model the best prediction of resectable tears. Results There were 92 meniscal tears (77 medial, 15 lateral). Interobserver agreement between clinical fellows and treating surgeons was poor to fair (κ < 0.4) for all clinical variables except radiographic measures, which were good. Fellows and surgeons predicted unstable meniscal tear preoperatively with equivalent accuracy of 60%. Logistic regression modelling revealed that a history of swelling and a ballottable effusion were negative predictors. A positive McMurray test was the only positive predictor of unstable meniscal tear. “Mechanical” symptoms were not reliable predictors in this prospective study. The model was 69% accurate for all patients and 76% for those with advanced medial compartment osteoarthritis defined by a joint space height of 2 mm or less. Conclusions This study underscored the difficulty in using clinical variables to predict unstable medial meniscal tears in patients with pre

  5. Comparison of meniscal fibrochondrocyte and synoviocyte bioscaffolds toward meniscal tissue engineering in the dog.

    PubMed

    Ballard, George A; Warnock, Jennifer J; Bobe, Gerd; Duesterdieck-Zellmer, Katja F; Baker, Lindsay; Baltzer, Wendy I; Ott, Jesse

    2014-10-01

    Tissue engineering is a promising field of study toward curing the meniscal deficient stifle; however the ideal cell type for this task is not known. We describe here the extraction of synoviocytes and meniscal fibrochondrocytes from arthroscopic debris from six dogs, which were cultured as tensioned bioscaffolds to synthesize meniscal-like fibrocartilage sheets. Despite the diseased status of the original tissues, synoviocytes and meniscal fibrochondrocytes had high viability at the time of removal from the joint. Glycosaminoglycan and collagen content of bioscaffolds did not differ. Meniscal fibrochondrocyte bioscaffolds contained more type II collagen, but collagen deposition was disorganized, with only 30-40% of cells viable. The collagen of synoviocyte bioscaffolds was organized into sheets and bands and 80-90% of cells were viable. Autologous, diseased meniscal fibrochondrocytes and synoviocytes are plausible cell sources for future meniscal tissue engineering research, however cell viability of meniscal fibrochondrocytes in the tensioned bioscaffolds was low. PMID:24856453

  6. Fast presurgical magnetic resonance imaging of meniscal tears and concurrent subchondral bone marrow lesions. Study of dogs with naturally occurring cranial cruciate ligament rupture.

    PubMed

    Olive, J; d'Anjou, M-A; Cabassu, J; Chailleux, N; Blond, L

    2014-01-01

    Meniscal tears and subchondral bone marrow lesions have both been described in dogs with cranial cruciate ligament rupture, but their possible concurrence has not been evaluated. In a population of 14 dogs exhibiting signs of stifle pain with surgically confirmed cranial cruciate ligament rupture, a short presurgical 1.5T magnetic resonance (MR) imaging protocol including dorsal proton density, dorsal T1-weighted gradient recalled echo, and sagittal fat-saturated dual echo sequences was tested to further investigate these features and illustrate meniscal tears. Interobserver agreement for detection of medial meniscal tears (k=0.83) and bone marrow lesions (k=0.87) was excellent. Consensus MR reading allowed detection of nine out of 12 surgically confirmed medial meniscal tears and there was no false positive. All dogs had cruciate ligament enthesis-related bone marrow lesions in the tibia, femur or both bones. Additionally, among the 12 dogs with confirmed medial meniscal tears, subchondral bone marrow lesions were present in the caudomedial (9 dogs) and caudoaxial (11 dogs) regions of the tibial plateau, resulting in odds ratios (13.6, p=0.12, and 38.3, p=0.04, respectively) that had large confidence intervals due to the small group size of this study. The other two dogs had neither tibial bone marrow lesions in these locations nor medial meniscal tears. These encouraging preliminary results warrant further investigation using this clinically realistic preoperative MR protocol. As direct diagnosis of meniscal tears remained challenging in dogs even with high-field MR, identification of associated signs such as subchondral bone marrow lesions might indirectly allow suspicion of an otherwise unrecognized meniscal tear. PMID:24226972

  7. 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

  8. Meniscal Allograft Transplantation: State of the Art.

    PubMed

    Trentacosta, Natasha; Graham, William C; Gersoff, Wayne K

    2016-06-01

    Meniscal allograft transplantation has evolved over the years to provide a state-of-the-art technique for the sports medicine surgeon to utilize in preserving contact mechanics and function of the knee in irreparable meniscal pathology. However, this procedure continues to spark considerable debate on proper tissue processing techniques, acceptable indications, methods of implantation, and potential long-term outcomes. PMID:27135295

  9. The Effect of Perioperative Ketorolac on the Clinical Failure Rate of Meniscal Repair

    PubMed Central

    Proffen, Benedikt L.; Nielson, Jason H.; Zurakowski, David; Micheli, Lyle J.; Curtis, Christine; Murray, Martha M.

    2014-01-01

    Background: There has been recent interest in the effect of nonsteroidal anti-inflammatory medications on musculoskeletal healing. No studies have yet addressed the effect of these medications on meniscal healing. Hypothesis: The administration of ketorolac in the perioperative period will result in higher rates of meniscal repair clinical failure. Study design: Cohort study; Level of evidence, 3. Methods: A total of 110 consecutive patients underwent meniscal repair at our institution between August 1998 and July 2001. Three patients were lost to follow-up, and the remaining 107 (mean age, 15.9 ± 4.4 years) had a minimum 5-year follow-up (mean follow-up, 5.5 years). Thirty-two patients (30%) received ketorolac perioperatively. The primary outcome measure was reoperation for continued symptoms of meniscal pathology. Asymptomatic patients were evaluated by the International Knee Documentation Committee (IKDC) Subjective Knee Form, Short Form–36 (SF-36) Health Survey, and Knee Outcome Osteoarthritis Score (KOOS). Results: Kaplan-Meier survivorship revealed no difference in reoperation rates with and without the administration of perioperative ketorolac (P = .95). There was an overall failure rate of 35% (37/107 patients), with a 34% failure rate in patients receiving ketorolac (11/32 patients). Multivariable Cox regression confirmed that age, duration of symptoms, meniscal tear type, fixation technique, concurrent anterior cruciate ligament repair, and ketorolac usage did not have an impact on the rate of failure (P > .05 for all; ketorolac use, P > .50). Female sex (P = .04) and medial location (P = .01) were predictive of an increased risk for reoperation. Conclusion: Failure of meniscal repair was not altered with the administration of perioperative ketorolac. Further work studying the effects of longer term anti-inflammatory use after meniscal repair is necessary before stating that this class of medications has no effect on meniscal healing. Clinical

  10. Meniscal injury: I. Basic science and evaluation.

    PubMed

    Greis, Patrick E; Bardana, Davide D; Holmstrom, Michael C; Burks, Robert T

    2002-01-01

    The patient with meniscal injury may present with pain, swelling, or mechanical symptoms and often requires surgical intervention for symptom resolution. Treatment of such injuries relies on understanding the gross and microanatomic features of the meniscus that are important in maintaining meniscal function. The ability of the meniscus to participate in load bearing, shock absorption, joint lubrication, and joint stability depends on the maintenance of its structural integrity. The diagnosis of meniscal injury often can be made by clinical evaluation utilizing the history, physical examination, and plain radiographs. Magnetic resonance imaging can be useful in confirming the diagnosis when clinical findings are inconclusive. Treatment depends on tear pattern, vascularity, and an assessment of tissue quality. Surgical decision making for the treatment of meniscal injury is based on patient factors and understanding of the meniscal structure, function, and pathology. PMID:12041938

  11. Differential neuronal changes in medial prefrontal cortex, basolateral amygdala and nucleus accumbens after postweaning social isolation.

    PubMed

    Wang, Yu-Chun; Ho, Ue-Cheung; Ko, Meng-Ching; Liao, Chun-Chieh; Lee, Li-Jen

    2012-04-01

    The mesocorticolimbic system contains dopamine (DA)-producing neurons in the ventral tegmental area (VTA) and their projection targets, including the medial prefrontal cortex (mPFC), amygdala (AMY) and nucleus accumbens (NAc). Disruption of this system might attribute to mental illnesses. In the present study, we adopted the postweaning social isolation paradigm to model neuropsychiatric disorders and studied the functional and structural changes of the mesocorticolimbic system. After 8-9 weeks of isolation, rats exhibited hyperlocomotor activity and impaired sensorimotor gating compared to group-reared controls. However, the number of tyrosine hydroxylase-positive VTA neurons and the volume of VTA were not affected. Comparing with group-reared controls, the DA levels in the isolation-reared were not altered in the VTA, mPFC and NAc but decreased in the AMY. In the structural aspect, dendritic features of layer II/III pyramidal mPFC neurons; pyramidal neurons in the basolateral nucleus of amygdala (BLA) and medium spiny neurons in the core region of the NAc (NAcc) were examined. Interestingly, the neuronal changes were region-specific. The mPFC neurons had reduced dendritic complexity, spine density and elongated terminal branches. The BLA neurons had extensive dendritic arbors with short branches but unchanged spine density. The NAcc neurons had reduced total dendritic length but the segment length and spine density remained the same. Together, the results demonstrated the structural and functional changes in the mesocorticolimbic DA system of socially isolated rats. These changes may account for the behavioral impairments in these rats and attribute to the susceptibility to mental disorders related to schizophrenia and depression. PMID:22002740

  12. Diagnostic accuracy of Magnetic Resonance Imaging in assessment of Meniscal and ACL tear: Correlation with arthroscopy

    PubMed Central

    Yaqoob, Jamal; Alam, Muhammad Shahbaz; Khalid, Nadeem

    2015-01-01

    Objective: To determine the diagnostic accuracy of magnetic resonance imaging (MRI) in injuries related to anterior cruciate ligament and menisci and compare its effectiveness with that of arthroscopy. Methods: This retrospective cross-sectional study was conducted in the department of Radiology & Medical Imaging of Dallah Hospital, Riyadh, Kingdom of Saudi Arabia from September 2012 to March 2014. Fifty four patients (including 30 men and 24 women) with internal derangement of knee referred from the orthopedic consulting clinics underwent MR imaging followed by arthroscopic evaluation. The presence of meniscal and ligamentous abnormality on the imaging was documented by two trained radiologist. Findings were later compared with arthroscopic findings. Results: The sensitivity, specificity and accuracy of MR imaging for menisci and ACL injury were calculated: 100% sensitivity, 88.4% specificity, 90% positive predictive value, 100% negative predictive value, and 94.4% accuracy were noted for medial meniscal injury. Similarly, MR had sensitivity of 85.7%, specificity of 95%, positive predictive value of 85.7%, negative predictive value of 95%, and accuracy of 92.5% for lateral meniscal injuries. Likewise, anterior cruciate ligament had 91.6% sensitivity, 95.2% specificity, 84.6% positive predictive value, 97.5% negative predictive value, and 94.4% accuracy. Conclusion: MRI is extremely helpful in identifying meniscal and anterior cruciate ligaments tears. MR imaging has high negative predictive value making it better choice as screening tool compared to diagnostic arthroscopic evaluation in most patients with soft tissue trauma to knee. PMID:26101472

  13. Effects of observer on the diagnostic accuracy of low-field MRI for detecting canine meniscal tears.

    PubMed

    Böttcher, Peter; Armbrust, Laura; Blond, Laurent; Brühschwein, Andreas; Gavin, Patrick R; Gielen, Ingrid; Hecht, Silke; Jurina, Konrad; Kneissl, Sibylle; Konar, Martin; Pujol, Esteban; Robinson, Andrew; Schaefer, Susan L; Theyse, Lars F H; Wigger, Antje; Ludewig, Eberhard

    2012-01-01

    Low-field MRI (lfMRI) has become increasingly accepted as a method for diagnosing canine meniscal tears in clinical practice. However, observer effects on diagnostic accuracy have not been previously reported. In this study, 50 consecutive stifle joints with clinical and radiologic evidence of cranial cruciate ligament insufficiency were investigated by lfMRI and arthroscopy. Fifteen observers who had varying levels of experience and who were unaware of arthroscopic findings independently reviewed lfMRI studies and recorded whether lateral and medial meniscal tears were present. Diagnostic accuracy (sensitivity, specificity, positive (PPV) and negative predictive value (NPV)) was determined for each observer and median values were calculated for all observers, using arthroscopy as the reference standard. Interrater agreement was determined based on intraclass correlation coefficient (ICC) analysis. Observer level of experience was compared with diagnostic sensitivity and specificity using correlation analysis. Based on pooled data for all observers, median sensitivity, specificity, PPV, and NPV for lfMRI diagnosis of lateral meniscal tears were 0.00, 0.94, 0.05, and 0.94, respectively. Median sensitivity, specificity, PPV, and NPV for medial meniscal tears were 0.74, 0.89, 0.83, and 0.79, respectively. Interrater agreement for all menisci was fair (0.51). Menisci were less consistently scored as having no tears (ICC = 0.13) than those scored as having tears (ICC = 0.50). No significant correlations between observer experience and diagnostic sensitivity/specificity were identified. Findings indicated that the accuracy of lfMRI for diagnosing canine meniscal tears was poor to fair and observer-dependent. Future studies are needed to develop standardized and widely accepted lfMRI criteria for diagnosing meniscal tears. PMID:22897385

  14. Extinction and Retrieval + Extinction of Conditioned Fear Differentially Activate Medial Prefrontal Cortex and Amygdala in Rats.

    PubMed

    Lee, Hongjoo J; Haberman, Rebecca P; Roquet, Rheall F; Monfils, Marie-H

    2015-01-01

    Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a footshock) leads to associative learning such that the tone alone comes to elicit a conditioned response (e.g., freezing). We have previously shown that an extinction session that occurs within the reconsolidation window (termed retrieval + extinction) attenuates fear responding and prevents the return of fear in Pavlovian fear conditioning (Monfils et al., 2009). To date, the mechanisms that explain the different behavioral outcomes between standard extinction and retrieval + extinction remain poorly understood. Here we sought to examine the differential temporal engagement of specific neural systems by these two approaches using Arc catFISH (cellular compartment analysis of temporal activity using fluorescence in situ hybridization (FISH)). Our results demonstrate that extinction and retrieval + extinction lead to differential patterns of expression, suggesting that they engage different networks. These findings provide insight into the neural mechanisms that allow extinction during reconsolidation to prevent the return of fear in rodents. PMID:26834596

  15. Extinction and Retrieval + Extinction of Conditioned Fear Differentially Activate Medial Prefrontal Cortex and Amygdala in Rats

    PubMed Central

    Lee, Hongjoo J.; Haberman, Rebecca P.; Roquet, Rheall F.; Monfils, Marie-H.

    2016-01-01

    Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a footshock) leads to associative learning such that the tone alone comes to elicit a conditioned response (e.g., freezing). We have previously shown that an extinction session that occurs within the reconsolidation window (termed retrieval + extinction) attenuates fear responding and prevents the return of fear in Pavlovian fear conditioning (Monfils et al., 2009). To date, the mechanisms that explain the different behavioral outcomes between standard extinction and retrieval + extinction remain poorly understood. Here we sought to examine the differential temporal engagement of specific neural systems by these two approaches using Arc catFISH (cellular compartment analysis of temporal activity using fluorescence in situ hybridization (FISH)). Our results demonstrate that extinction and retrieval + extinction lead to differential patterns of expression, suggesting that they engage different networks. These findings provide insight into the neural mechanisms that allow extinction during reconsolidation to prevent the return of fear in rodents. PMID:26834596

  16. FUNCTIONAL EVOLUTION OF MENISCAL REPAIR USING ABSORBABLE IMPLANTS

    PubMed Central

    Júnior, Waldo Lino

    2015-01-01

    To evaluate the functional evolution of knees after repair of longitudinal meniscal rupture with absorbable arrow implant. Methods: Between June 1997 and February 2001, 23 patients with a mean age of 26.3 years were evaluated. The mean follow-up time was 72.87 months (45-96). We performed 19 medial and 4 lateral meniscal repairs. The patients were pre and postoperatively evaluated regarding joint function according to the Lysholm scale, and, postoperatively, according to IKDC. Results: For better understanding, the 23 treated cases were divided into three groups. Twenty one had ACL injuries, eleven of whom were submitted to ligament reconstruction (Group I). All these 11 cases were regarded as satisfactory. The remaining 10 cases of the 21 with ACL lesion were not submitted to ligament reconstruction (Group II). Of these, 5 evolved satisfactorily, not requiring ligament reconstruction. The remaining five evolved with complaint of ligament instability, being all submitted to reconstruction. Four of these had an integral meniscus and one presented a failure of the medial meniscus. The remaining two cases who did not present ACL injury (Group III), one patient evolved satisfactorily and one developed a failure of the lateral meniscus. According to the Lysholm scale, preoperative mean score was 57.53 and the postoperative mean score was 86.95, evidencing a statistically significant improvement (Wilcoxon p < 0.01). The non-parametric ANOVA was employed for ordinal data with repeated measurements to assess pre- and postoperative measurements, considering Groups I and II. We assessed knee stabilization and found no statistically significant difference between Groups I and II (p = 0.648). Even if there were differences between the two groups, both had the same behavior. On postoperative assessment with IKDC, 4 patients were grade A, 13 were grade B, and 6 were grade C. Two C results were caused by a meniscal rupture. Conclusion: Of the 23 patients, only two presented known

  17. Clinical and arthroscopic features of meniscal tears and a search for the role of infection in histologically confirmed meniscal mucoid degeneration.

    PubMed

    Boya, Hakan; Pinar, Halit; Gülay, Zeynep; Oktay, Gülgün; Ozer, Erdener

    2004-07-01

    Mucoid degeneration (MD) of the meniscus has received little attention. The pathology deserves special interest as it may lead to loss of the meniscus even in very young individuals. The cause of MD and the clinical features of meniscal tears due to that pathology have not been understood. This study analyzed the age profile and the role of trauma in patients with torn menisci with MD, examined meniscal tear patterns and clinical features, and investigated the role of bacterial infection in causing MD. Meniscal samples obtained from 27 consecutive patients during arthroscopic resection of torn menisci considered to be due to MD (typical yellow color) underwent pathological investigation. The samples were scored according to the light microscopic criteria of Copenhaver; 24 menisci (23 patients) with stage 2-3 MD comprised the study group. Magnetic resonance imaging obtained in 11 patients typically revealed increased intrasubstance signal intensity that extended to at least one of the meniscal surfaces. Pieces of resected meniscal tissue were also subject to PCR investigation to search for presence of bacteria. Of the 24 knees 21 (87%) had no history of trauma. Mean Tegner activity level was 4 (1 and 7). Mean duration of symptoms was 11.6 months (1-36). Pain was the most frequent symptom ( n=22). Joint line tenderness and McMurray's test (pain and/or clicking) were present in 22 and 16 knees, respectively. Medial meniscus was affected in 16 and lateral meniscus in 8. Meniscal cyst and incomplete discoid meniscus was present in 5 and 2 of the lateral menisci. All of the torn menisci were degenerated and yellow in color. The most common tear patterns were radial and/or flap, and longitudinal-horizontal tears. PCR study revealed no bacteria. Mucoid degeneration of the meniscus does not seem to be related to the aging process. Clinical findings of torn such menisci are insidious compared to traumatic tears. Lack of history of trauma may delay the diagnosis. Bacterial

  18. 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.

  19. Kinetic study of the replacement of porcine small intestinal submucosa grafts and the regeneration of meniscal-like tissue in large avascular meniscal defects in dogs.

    PubMed

    Cook, J L; Tomlinson, J L; Arnoczky, S P; Fox, D B; Reeves Cook, C; Kreeger, J M

    2001-06-01

    Porcine small intestinal submucosa (SIS) was used to replace large, avascular defects in the medial menisci of dogs. Twelve dogs received SIS grafts and 3 dogs were left untreated as controls. Dogs were evaluated at 4, 8, and 12 weeks by means of lameness scoring and ultrasonography. Dogs were sacrificed at 1, 6, or 12 weeks after implantation, and the tissue at the site of meniscal resection was evaluated for gross and histologic appearance, cross-sectional and surface area, and collagen types I and II. The femoral and tibial condyles were assessed for articular cartilage damage. Control dogs were significantly more lame than grafted dogs 8 and 12 weeks after instrumentation. Grafted dogs' replacement tissue appeared meniscal-like when evaluated grossly and ultrasonographically 12 weeks after instrumentation. The amount of replacement tissue was significantly greater in both cross-sectional and surface area for grafted dogs than for controls at all time points. Histologically, the SIS biomaterial could be identified in all grafted dogs at 1 week post-implantation, but in none at 6 weeks post-implantation. Subjectively, grafted dogs' replacement tissue was histologically superior to that of controls with respect to tissue type, organization, and architecture. Collagen types I and II immunoreactivity in grafted menisci were similar to that of normal menisci. Control dogs had significantly more articular cartilage damage than grafted dogs. SIS appears to induce regeneration of meniscal-like tissue in large, avascular meniscal defects in dogs, resulting in superior clinical function and articular cartilage protection compared to ungrafted controls. PMID:11429152

  20. Rehabilitation of meniscal injury and surgery.

    PubMed

    Cavanaugh, John T

    2014-12-01

    Meniscal cartilage plays an essential role in the function and biomechanics of the knee joint. The meniscus functions in load bearing, load transmission, shock absorption, joint stability, joint lubrication, and joint congruity. Individuals today are increasingly more active in later decades of life. Although the incidence of meniscal pathology is difficult to estimate, this increased exposure to athletic activity increases the risk of injury to these structures. Hede and coworkers reported the mean annual incidence of meniscus tears as 9.0 in males and 4.2 in females per 10,000 inhabitants. Tears were found to be more common in the third, fourth, and fifth decades of life. It has become clearer in recent decades that meniscal excision leads to articular cartilage degeneration. Degenerative changes have been found to be directly proportional to the amount of meniscus removed. Therefore, it has been generally recognized that the amount of meniscal tissue removed should be minimized, repaired, or replaced. Whether a meniscal lesion is treated conservatively or surgically, the rehabilitation program will play an important role in the functional outcome. This article will discuss these programs and the various treatment strategies employed. PMID:25390473

  1. Meniscal allograft transplantation in rabbit.

    PubMed

    Vilela, Liana M; Del Carlo, Ricardo J; Melo Filho, Edson V; Favarato, Lukiya S C; Duarte, Tatiana S; Pontes, Kelly C S; Cunha, Daise N Q

    2015-01-01

    This study evaluated the technique for meniscal allograft transplantation using allografts preserved in glycerin 98% in rabbits. Euthanasia was performed at 70 days to compare the transplanted (TM1 to TM16) versus the contralateral meniscus (OM1 to OM16). Sixteen menisci, 8 transplanted and 8 contralateral, were submitted to gross examination, histomorphometric analysis for identification and quantification of cellular type, and for quantification and distribution of collagen fibers. A revascularization study was conducted in all of the other samples. Lengths of the OM varied from 0.9 to 1.0 cm and two TM were smaller. All TM were completely attached to the synovial membrane, except for one case that presented partial fixation. Both, TM and OM had similar amounts of chondrocytes, fibroblasts and fibrocytes, and at the horns, chondrocytes were predominant. The collagen fibers in TM were well organized throughout the body, and disorganized at the horns. These fibers in OM were organized. The amounts of collagen type I and III, and the vascularization of the perimeniscal tissue and of the edge were similar in OM and TM. These results demonstrated graft integration and thus this transplantation technique and preservation method may be recommended. PMID:26648544

  2. Glutaraldehyde-cross-linked meniscal allografts: mechanical properties.

    PubMed

    Wisnewski, P J; Powers, D L; Kennedy, J M

    1988-01-01

    Removal of a severely damaged medial meniscus has been shown to lead to degradation of the articular cartilage and formation of degenerative arthritis. To counter this degenerative effect, meniscal prostheses, including glutaraldehyde-cross-linked allografts, have been evaluated in dogs. The purpose of this research was to quantify the mechanical properties of both fresh and glutaraldehyde-cross-linked canine medial menisci. Mechanical properties quantified were tensile strength, tensile modulus, and compressive stiffness. In addition, water content of compressive test samples was measured. Analysis of variance showed significantly lower tensile strength and tensile modulus and significantly higher compressive stiffness for the glutaraldehyde-cross-linked menisci, as compared to fresh specimens. Measurement of the weight percentage of water in fresh and cross-linked samples revealed no significant differences in water content. When implanted into a joint, the increased compressive stiffness could increase the peripheral tensile load. Due to the decreased tensile strength in this region, the prosthetic meniscus could be susceptible to peripheral tears. PMID:3155295

  3. The clinical value of magnetic resonance imaging in the evaluation of meniscal disorders.

    PubMed

    Raunest, J; Oberle, K; Loehnert, J; Hoetzinger, H

    1991-01-01

    This prospective double-blind study was designed to evaluate the capability of magnetic resonance imaging to serve as a diagnostic tool in patients who have a clinically suspected disorder of the meniscus. The imaging studies provided a diagnostic accuracy of 72 per cent, a sensitivity of 88 per cent, and a specificity of 57 per cent. The positive and negative predictive values were 66 and 83 per cent. The diagnostic sensitivity was 94 per cent for lesions of the medial meniscus; this value differed significantly from that of 78 per cent for lesions of the lateral meniscus (p less than 0.05). The 37 per cent specificity for lesions of the medial meniscus was extremely low compared with the rate of 69 per cent for lesions of the lateral meniscus (p less than 0.01). In the intermediate part of the meniscus, the diagnostic sensitivity was 37 per cent on the medial side and 23 per cent on the lateral side; these values were significantly less than the average of 74 per cent for the other meniscal segments (p less than 0.001). The imaging studies provided an over-all accuracy of 67 per cent in the detection of degeneration of the meniscus, 78 per cent in the identification of meniscal tears, and 82 per cent in the delineation of postoperative lesions. PMID:1985979

  4. Meniscal allograft transplantation: rationale for treatment.

    PubMed

    Smith, N A; Costa, M L; Spalding, T

    2015-05-01

    The anatomy and microstructure of the menisci allow the effective distribution of load across the knee. Meniscectomy alters the biomechanical environment and is a potent risk factor for osteoarthritis. Despite a trend towards meniscus-preserving surgery, many tears are irreparable, and many repairs fail. Meniscal allograft transplantation has principally been carried out for pain in patients who have had a meniscectomy. Numerous case series have reported a significant improvement in patient-reported outcomes after surgery, but randomised controlled trials have not been undertaken. It is scientifically plausible that meniscal allograft transplantation is protective of cartilage, but this has not been established clinically to date. PMID:25922450

  5. Meniscal allograft transplant in a 16-year-old male soccer player: A case report

    PubMed Central

    Menta, Roger; Howitt, Scott

    2014-01-01

    Meniscal allograft transplantation (MAT) is a relatively new procedure that has gained popularity in the last couple of decades as a possible alternative to a meniscectomy to provide significant pain relief, improve function, and prevent the early onset of degenerative joint disease (DJD). As of present, evidence is limited and conflicting on the success of such procedures. In this case, a 16-year old male athlete underwent numerous surgical procedures to correct a left anterior cruciate ligament (ACL) rupture with associated medial and lateral meniscal damage that occurred as a result of a non-contact mechanism of injury. Following multiple procedures, including repair of both menisci and follow-up partial meniscectomy of the lateral meniscus, the patient continued to experience symptoms on the left lateral knee, making him a candidate for MAT. This case is used to highlight what a MAT is, what makes someone a candidate for this type of procedure, the current evidence surrounding the success of this intervention, and some rehabilitation considerations following surgery. The role of chiropractors and primary clinicians is to ensure that young athletes undergo early intervention to offset any degenerative changes that would be associated with sustained meniscal lesions. PMID:25550669

  6. Meniscal allograft transplant in a 16-year-old male soccer player: A case report.

    PubMed

    Menta, Roger; Howitt, Scott

    2014-12-01

    Meniscal allograft transplantation (MAT) is a relatively new procedure that has gained popularity in the last couple of decades as a possible alternative to a meniscectomy to provide significant pain relief, improve function, and prevent the early onset of degenerative joint disease (DJD). As of present, evidence is limited and conflicting on the success of such procedures. In this case, a 16-year old male athlete underwent numerous surgical procedures to correct a left anterior cruciate ligament (ACL) rupture with associated medial and lateral meniscal damage that occurred as a result of a non-contact mechanism of injury. Following multiple procedures, including repair of both menisci and follow-up partial meniscectomy of the lateral meniscus, the patient continued to experience symptoms on the left lateral knee, making him a candidate for MAT. This case is used to highlight what a MAT is, what makes someone a candidate for this type of procedure, the current evidence surrounding the success of this intervention, and some rehabilitation considerations following surgery. The role of chiropractors and primary clinicians is to ensure that young athletes undergo early intervention to offset any degenerative changes that would be associated with sustained meniscal lesions. PMID:25550669

  7. Meniscal injuries: Detection using MR imaging

    SciTech Connect

    Reicher, M.A.; Hartzman, S.; Duckwiler, G.R.; Bassett, L.W.; Anderson, L.J.; Gold, R.H.

    1986-06-01

    Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a sole-noid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears.

  8. Macroscopic and Histological Evaluations of Meniscal Allograft Transplantation Using Gamma Irradiated Meniscus: A Comparative in Vivo Animal Study

    PubMed Central

    Zhang, Jin; Song, Guan-Yang; Chen, Xing-Zuo; Li, Yue; Li, Xu; Zhou, Jun-Lin

    2015-01-01

    Background: Many studies suggest that the gamma irradiation decreases allograft strength in a dose-dependent manner. However, no study has demonstrated that this decrease in strength translates into higher failure rate in meniscal allograft transplantation (MAT). The aim of this study was to investigate the effects of gamma irradiation on macroscopic and histological alterations of transplanted meniscal tissue and joint cartilage after MAT. Methods: Medial total meniscectomies were performed on the right knees of 60 New Zealand white rabbits. All meniscal allografts were divided into three groups (20 in each group) and then sterilized with 0 Mrad, 1.5 Mrad, or 2.5 Mrad of gamma irradiation. For each group, 5 menisci were randomly chosen for scanning electron microscopic (SEM) analysis and the remaining 15 were prepared for MAT surgeries. Forty-five right knees received MAT surgeries (0 Mrad group, 1.5 Mrad group, 2.5 Mrad group, 15 in each group), whereas the remaining 15 only received medial meniscectomy (Meni group). The left knees of the Meni group were chosen as the Sham group (n = 15). All the rabbits were sacrificed at week 24 postoperatively. Cartilage of the medial compartment of each group was evaluated macroscopically using the International Cartilage Repair Society (ICRS) score and then histologically using the Mankin score based on the Masson Trichrome staining. Results: The SEM analysis confirmed that the meniscal collagen fibers would be significantly damaged as the dose of gamma irradiation increased. At week 24, the overall scores of macroscopic evaluations of the transplanted meniscal tissue showed no significant differences among the three groups receiving MAT surgeries, except for 2 in the 2.5 Mrad group presented partial radial tears at midbody. The ICRS scores and the Mankin scores showed the lowest in the Sham group and the highest in the Meni group (P < 0.05). For the three groups receiving MAT surgeries, the 2.5 Mrad group showed significant

  9. Meniscus maturation in the swine model: changes occurring along with anterior to posterior and medial to lateral aspect during growth.

    PubMed

    Di Giancamillo, Alessia; Deponti, Daniela; Addis, Alessandro; Domeneghini, Cinzia; Peretti, Giuseppe M

    2014-10-01

    The meniscus plays important roles in knee function and mechanics and is characterized by a heterogeneous matrix composition. The changes in meniscus vascularization observed during growth suggest that the tissue-specific composition may be the result of a maturation process. This study has the aim to characterize the structural and biochemical variations that occur in the swine meniscus with age. To this purpose, menisci were collected from young and adult pigs and divided into different zones. In study 1, both lateral and medial menisci were divided into the anterior horn, the body and the posterior horn for the evaluation of glycosaminoglycans (GAGs), collagen 1 and 2 content. In study 2, the menisci were sectioned into the inner, the intermediate and the outer zones to determine the variations in the cell phenotype along with the inner-outer direction, through gene expression analysis. According to the results, the swine meniscus is characterized by an increasing enrichment in the cartilaginous component with age, with an increasing deposition in the anterior horn (GAGs and collagen 2; P < 0.01 both); moreover, this cartilaginous matrix strongly increases in the inner avascular and intermediate zone, as a consequence of a specific differentiation of meniscal cells towards a cartilaginous phenotype (collagen 2, P < 0.01). The obtained data add new information on the changes that accompany meniscus maturation, suggesting a specific response of meniscal cells to the regional mechanical stimuli in the knee joint. PMID:25216283

  10. 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

  11. 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

  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 cast immobilization on meniscal healing. An experimental study in the dog.

    PubMed

    Dowdy, P A; Miniaci, A; Arnoczky, S P; Fowler, P J; Boughner, D R

    1995-01-01

    A 1.5-cm longitudinal, full-thickness incision was made in the vascularized portion of the medial meniscus in 20 adult dogs and anatomically repaired. Postoperatively, the animals were either placed in a long leg cast (N = 9) or mobilized immediately (N = 11). The animals were sacrificed at 2 weeks (6 dogs), 4 weeks (6 dogs), or 10 weeks (8 dogs). Five medial menisci from the nonoperated side were used as controls. Collagen content was measured using a digital image analysis system, and the collagen percentage in the repair tissue in each postoperative treatment group was compared. In the 2-week and 4-week groups, there was no statistically significant difference in the percentage of collagen between those animals immobilized versus those that had early mobilization. The animals in the 10-week group that were mobilized had a significantly greater collagen percentage in the healing meniscal incision than those that were cast immobilized (44.6% +/- 10% versus 27.0% +/- 11%, P < 0.0001). There was no significant difference in the collagen percentages between the mobilized 10-week group and the contralateral control menisci group. All other menisci had a decreased collagen percentage compared with the controls. Prolonged immobilization decreases collagen formation in healing menisci. Thus, our results suggest that patients undergoing isolated meniscal repair either be immediately mobilized after surgery or immobilized for short periods only. PMID:8600741

  14. An arthroscopic analysis of lateral meniscal variants and a comparison with MRI findings.

    PubMed

    Kim, Yong-Goo; Ihn, Joo-Chul; Park, Seong-Ki; Kyung, Hee-Soo

    2006-01-01

    We reviewed 164 consecutive cases (158 patients) of arthroscopic examinations for lateral meniscal variants during the last 10 years. We classified lateral meniscal variants into four types by arthroscopic appearance, into six tear patterns by modifying O'Connor's classification, and compared magnetic resonance images (MRI) with arthroscopic findings. Regarding the four types, 131 cases were complete, 25 cases were incomplete, 4 cases were Wrisberg, and 4 cases were ring-shaped meniscus. The six tear patterns were as follows: 33 simple horizontal, 21 combined horizontal, 37 longitudinal, 27 central, 14 complex, and 12 radial tear. Among the 31 knees with a central tear or ring-shaped meniscus, we reviewed 25 MR images. Fifteen (60%) MRI findings were interpreted to represent a bucket-handle (displaced) tear of the normal C-shaped meniscus; 7(28%) MRI findings, a discoid meniscal tear; and the remaining 3(12%) MRI findings, a simple meniscal tear. Moreover, all ring-shaped menisci were interpreted as a displaced lateral meniscal tear on the MRI findings. Twelve patients (13 knees, 7.9%) had osteochondritis dissecans: Nine patients (10 knees) of them had a central tear, two patients (2 knees) of them had a simple horizontal tear of the discoid meniscus, and one patient (1 knee) had a ring-shaped meniscus. Twenty three patients (92.6%) with a central tear of the discoid meniscus did not have any traumatic events. For the differential diagnosis of a central tear or a ring-shaped meniscus from a bucket-handle tear of the normal C-shaped meniscus, we should take a careful history, in particular any traumatic events, we should also consider the possibility of misinterpreting the MR images though these images can provide additional information about associated abnormalities and probe carefully in the arthroscopic operations. PMID:15905996

  15. [Meniscal transplantation with a synovial pedicle--an animal experiment].

    PubMed

    Fukushima, K

    1993-12-01

    The effect of a meniscal transplantation with a synovial pedicle in the avascular portion of the meniscus was investigated in an animal model. An inner (free edge side) half of the middle segment of the medial meniscus, about 6 mm in length, of an adult dog was resected, and a half thickness of the remaining outer (peripheral) meniscus was advanced with a synovial pedicle to fill in the resected portion and sutured with 6-0 interrupted Nylon sutures. As a control, the same procedure without the synovial pedicle was performed for comparison. Twenty-four dogs were treated with synovial pedicle and 13 without. The treated meniscus was excised every four weeks postoperatively up to 32 weeks for gross observation and histological examination. The histological findings at the junction between the advanced meniscus and the remaining meniscus in the group with the synovial pedicle were as follows: 1) At eight to 20 weeks, vascular proliferation and fibroblasts formation were present. 2) At 24 weeks, the vascularity decreased and the junction was filled with collagen fibers. 3) At 32 weeks, the junction was almost completely repaired with chondrocytes. In contrast, in the group without the synovial pedicle, the junction was connected with fibrous tissue, but with no chondrocytes even at 32 weeks. This enhancement of the meniscus repair with the synovial pedicle was considered to be due to reparative ability of the synovial cells, neovascularization through the synovium and viability of the advanced meniscus.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7508485

  16. Lateral Meniscal Allograft Transplantation: The Bone Trough Technique.

    PubMed

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

    2016-04-01

    The lateral meniscus plays a critical role in the stability and health of the knee. Treating patients who have undergone a total lateral meniscectomy or functional equivalent is challenging, especially young and active patients. Current literature regarding meniscal tears supports that repair should be the first surgical option. Moreover, it is recommended to preserve as much meniscal tissue as possible. In cases in which a total or functional meniscectomy is a pre-existing condition, a lateral meniscal allograft transplantation is a possible option. The purpose of this surgical technique description was to detail the method of lateral meniscal allograft transplantation using a bone trough. PMID:27462536

  17. A Porcine Animal Model for Early Meniscal Degeneration – Analysis of Histology, Gene Expression and Magnetic Resonance Imaging Six Months after Resection of the Anterior Cruciate Ligament

    PubMed Central

    Kreinest, Michael; Reisig, Gregor; Ströbel, Philipp; Dinter, Dietmar; Attenberger, Ulrike; Lipp, Peter; Schwarz, Markus

    2016-01-01

    Background/Objective The menisci of the mammalian knee joint balance the incongruence between femoral condyle and tibial plateau and thus menisci absorb and distribute high loads. Degeneration processes of the menisci lead to pain syndromes in the knee joint. The origin of such degenerative processes on meniscal tissue is rarely understood and may be described best as an imbalance of anabolic and catabolic metabolism. A standardized animal model of meniscal degeneration is needed for further studies. The aim of the current study was to develop a porcine animal model with early meniscal degeneration. Material and Methods Resection of the anterior cruciate ligament (ACLR) was performed on the left knee joints of eight Göttingen minipigs. A sham operation was carried out on the right knee joint. The grade of degeneration was determined 26 weeks after the operation using histology and magnetic resonance imaging (MRI). Furthermore, the expression of 14 genes which code for extracellular matrix proteins, catabolic matrix metalloproteinases and inflammation mediators were analyzed. Results Degenerative changes were detected by a histological analysis of the medial meniscus after ACLR. These changes were not detected by MRI. In terms of their gene expression profile, these degenerated medial menisci showed a significantly increased expression of COL1A1. Conclusion This paper describes a new animal model for early secondary meniscal degeneration in the Göttingen minipig. Histopathological evidence of the degenerative changes could be described. This early degenerative changes could not be seen by NMR imaging. PMID:27434644

  18. Quantitative differences in the histology of the attachment zones of the meniscal horns in the knee joint of man.

    PubMed Central

    Benjamin, M; Evans, E J; Rao, R D; Findlay, J A; Pemberton, D J

    1991-01-01

    The attachment zones of the meniscal horns of 7 dissecting room cadavers were examined by routine histology. All the knees were devoid of gross pathological change and no discoid menisci were included. Significant differences are reported in the thickness of the zones of uncalcified fibrocartilage and cortical calcified tissue (calcified fibrocartilage and underlying lamellar bone) and in the percentage of bone:bone marrow. There was a thicker zone of uncalcified fibrocartilage and a greater quantity of calcified tissue at the horns of the lateral than the medial meniscus. The differences in uncalcified fibrocartilage were largely attributable to the posterior horns, but the variations in calcified tissue mainly reflected differences between the anterior horns. It is suggested that the greater mobility of the lateral meniscus and the blending of its anterior horn with the anterior cruciate ligament are important factors accounting for the quantitative differences in the meniscal attachment zones. Images Fig. 2 Fig. 3 PMID:1769887

  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. Transplantation of Achilles Tendon Treated With Bone Morphogenetic Protein 7 Promotes Meniscus Regeneration in a Rat Model of Massive Meniscal Defect

    PubMed Central

    Ozeki, Nobutake; Muneta, Takeshi; Koga, Hideyuki; Katagiri, Hiroki; Otabe, Koji; Okuno, Makiko; Tsuji, Kunikazu; Kobayashi, Eiji; Matsumoto, Kenji; Saito, Hirohisa; Saito, Tomoyuki; Sekiya, Ichiro

    2013-01-01

    Objective This study was undertaken to examine whether bone morphogenetic protein 7 (BMP-7) induces ectopic cartilage formation in the rat tendon, and whether transplantation of tendon treated with BMP-7 promotes meniscal regeneration. Additionally, we analyzed the relative contributions of host and donor cells on the healing process after tendon transplantation in a rat model. Methods BMP-7 was injected in situ into the Achilles tendon of rats, and the histologic findings and gene profile were evaluated. Achilles tendon injected with 1 μg of BMP-7 was transplanted into a meniscal defect in rats. The regenerated meniscus and articular cartilage were evaluated at 4, 8, and 12 weeks. Achilles tendon from LacZ-transgenic rats was transplanted into the meniscal defect in wild-type rats, and vice versa. Results Injection of BMP-7 into the rat Achilles tendon induced the fibrochondrocyte differentiation of tendon cells and changed the collagen gene profile of tendon tissue to more closely approximate meniscal tissue. Transplantation of the rat Achilles tendon into a meniscal defect increased meniscal size. The rats that received the tendon treated with BMP-7 had a meniscus matrix that exhibited increased Safranin O and type II collagen staining, and showed a delay in articular cartilage degradation. Using LacZ-transgenic rats, we determined that the regeneration of the meniscus resulted from contribution from both donor and host cells. Conclusion Our findings indicate that BMP-7 induces ectopic cartilage formation in rat tendons. Transplantation of Achilles tendon treated with BMP-7 promotes meniscus regeneration and prevents cartilage degeneration in a rat model of massive meniscal defect. Native cells in the rat Achilles tendon contribute to meniscal regeneration. PMID:23897174

  1. Assessment of tibial rotation and meniscal movement using kinematic magnetic resonance imaging

    PubMed Central

    2014-01-01

    Objective This work aimed to assess tibial rotations, meniscal movements, and morphological changes during knee flexion and extension using kinematic magnetic resonance imaging (MRI). Methods Thirty volunteers with healthy knees were examined using kinematic MRI. The knees were imaged in the transverse plane with flexion and extension angles from 0° to 40° and 40° to 0°, respectively. The tibial interior and exterior rotation angles were measured, and the meniscal movement range, height change, and side movements were detected. Results The tibia rotated internally (11.55° ± 3.20°) during knee flexion and rotated externally (11.40° ± 3.0°) during knee extension. No significant differences were observed between the internal and external tibial rotation angles (P > 0.05), between males and females (P > 0.05), or between the left and right knee joints (P > 0.05). The tibial rotation angle with a flexion angle of 0° to 24° differed significantly from that with a flexion angle of 24° to 40° (P < 0.01). With knee flexion, the medial and lateral menisci moved backward and the height of the meniscus increased. The movement range was greater in the anterior horn than in the posterior horn and greater in the lateral meniscus than in the medial meniscus (P < 0.01). During backward movements of the menisci, the distance between the anterior and posterior horns decreased, with the decrease more apparent in the lateral meniscus (P < 0.01). The side movements of the medial and lateral menisci were not obvious, and a smaller movement range was found than that of the forward and backward movements. Conclusion Knee flexion and extension facilitated internal and external tibial rotations, which may be related to the ligament and joint capsule structure and femoral condyle geometry. PMID:25142267

  2. Muscarinic receptor subtypes differentially control synaptic input and excitability of cerebellum-projecting medial vestibular nucleus neurons.

    PubMed

    Zhu, Yun; Chen, Shao-Rui; Pan, Hui-Lin

    2016-04-01

    Neurons in the vestibular nuclei have a vital function in balance maintenance, gaze stabilization, and posture. Although muscarinic acetylcholine receptors (mAChRs) are expressed and involved in regulating vestibular function, it remains unclear how individual mAChR subtypes regulate vestibular neuronal activity. In this study, we determined which specific subtypes of mAChRs control synaptic input and excitability of medial vestibular nucleus (MVN) neurons that project to the cerebellum. Cerebellum-projecting MVN neurons were labeled by a fluorescent retrograde tracer and then identified in rat brainstem slices. Quantitative PCR analysis suggested that M2 and M3 were the possible major mAChR subtypes expressed in the MVN. The mAChR agonist oxotremorine-M significantly reduced the amplitude of glutamatergic excitatory post-synaptic currents evoked by stimulation of vestibular primary afferents, and this effect was abolished by the M2-preferring antagonist AF-DX 116. However, oxotremorine-M had no effect on GABA-mediated spontaneous inhibitory post-synaptic currents of labeled MVN neurons. Furthermore, oxotremorine-M significantly increased the firing activity of labeled MVN neurons, and this effect was blocked by the M3-preferring antagonist J104129 in most neurons tested. In addition, AF-DX 116 reduced the onset latency and prolonged the excitatory effect of oxotremorine-M on the firing activity of labeled MVN neurons. Our findings suggest that M3 is the predominant post-synaptic mAChR involved in muscarinic excitation of cerebellum-projecting MVN neurons. Pre-synaptic M2 mAChR regulates excitatory glutamatergic input from vestibular primary afferents, which in turn influences the excitability of cerebellum-projecting MVN neurons. This new information has important therapeutic implications for treating vestibular disorders with mAChR subtype-selective agents. Medial vestibular nucleus (MVN) neurons projecting to the cerebellum are involved in balance control. We

  3. The Use of Blood Vessel–Derived Stem Cells for Meniscal Regeneration and Repair

    PubMed Central

    OSAWA, AKI; HARNER, CHRISTOPHER D.; GHARAIBEH, BURHAN; MATSUMOTO, TOMOYUKI; MIFUNE, YUTAKA; KOPF, SEBASTIAN; INGHAM, SHEILA J. M.; SCHREIBER, VERENA; USAS, ARVYDAS; HUARD, JOHNNY

    2015-01-01

    Purpose Surgical repairs of tears in the vascular region of the meniscus usually heal better than repairs performed in the avascular region; thus, we hypothesized that this region might possess a richer supply of vascular-derived stem cells than the avascular region. Methods In this study, we analyzed 6 menisci extracted from aborted human fetuses and 12 human lateral menisci extracted from adult human subjects undergoing total knee arthroplasty. Menisci were immunostained for CD34 (a stem cell marker) and CD146 (a pericyte marker) in situ, whereas other menisci were dissected into two regions (peripheral and inner) and used to isolate meniscus-derived cells by flow cytometry. Cell populations expressing CD34 and CD146 were tested for their multi-lineage differentiation potentials, including chondrogenic, osteogenic, and adipogenic lineages. Fetal peripheral meniscus cells were transplanted by intracapsular injection into the knee joints of an athymic rat meniscal tear model. Rat menisci were extracted and histologically evaluated after 4 wk posttransplantation. Results Immunohistochemistry and flow cytometric analyses demonstrated that a higher number of CD34- and CD146-positive cells were found in the peripheral region compared with the inner region. The CD34- and CD146-positive cells isolated from the vascular region of both fetal and adult menisci demonstrated multilineage differentiation capacities and were more potent than cells isolated from the inner (avascular) region. Fetal CD34- and CD146-positive cells transplanted into the athymic rat knee joint were recruited into the meniscal tear sites and contributed to meniscus repair. Conclusions The vascularized region of the meniscus contains more stem cells than the avascular region. These meniscal-derived stem cells were multi-potent and contributed to meniscal regeneration. PMID:23247715

  4. 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

  5. Differential role of temporoparietal junction and medial prefrontal cortex in causal inference in autism: an independent component analysis.

    PubMed

    Murdaugh, Donna L; Nadendla, Kavita D; Kana, Rajesh K

    2014-05-01

    Neuroimaging studies have consistently identified a network of brain regions responsible for making inferences of others' mental states. This network includes the medial prefrontal cortex (MPFC), posterior superior temporal sulcus (pSTS) at the temporoparietal junction (TPJ), and temporal poles. Although TPJ and MPFC are key nodes of the Theory of Mind (ToM) network, their relative functional roles are still debated. This study sought to examine the contribution of these regions in causal attribution and to explore the nature of the ToM network in people with autism spectrum disorders (ASD). Participants watched a series of comic strip vignettes in the MRI scanner, and identified the most logical ending to each vignette, which sometimes required intentional causal attribution. Independent component analysis was done to isolate temporally correlated brain networks. The functional networks for intentional causality included the TPJ and MPFC, with an increased contribution of TPJ. There was also a significant group difference in the TPJ, with reduced response in participants with ASD. These results suggest an increased role of TPJ in intentional causality. In addition, the reduced response in ASD in TPJ may reflect their difficulties in social cognition. PMID:24695086

  6. Joint degeneration following meniscal allograft transplantation in a canine model: mechanical properties and semiquantitative histology of articular cartilage.

    PubMed

    Elliott, Dawn M; Jones, Relief; Setton, Lori A; Scully, Sean P; Vail, T Parker; Guilak, Farshid

    2002-03-01

    This study examined the hypothesis that meniscal allograft transplantation serves a "chondroprotective" role and prevents the histological and biomechanical changes of the articular cartilage following meniscectomy. Skeletally mature mongrel dogs underwent total medial meniscectomy and received either a fresh meniscal allograft ( n=10) or no further treatment ( n=10). Semiquantitative histology and biomechanical analysis of the femoral articular cartilage was used to assess cartilage pathology 12 weeks following surgery. Histological analysis showed significant changes in cartilage structure that did not differ between the meniscectomy and allograft transplantation groups. Similarly, the tensile modulus of the surface zone cartilage was significantly lower than that in unoperated controls following either meniscectomy or allograft transplantation. A significant correlation was observed between the biomechanical and histological changes, suggesting that degenerative changes in cartilage structure and mechanical function are interrelated. Our findings do not support the hypothesis that meniscal allograft transplantation provides chondroprotection of the femoral condyle and also suggest that it does not lead to increased degenerative changes. PMID:11914769

  7. Timing of Anterior Cruciate Ligament Reconstruction and Incidence of Meniscal and Chondral Injury within the Knee

    PubMed Central

    Razi, Mohammad; Salehi, Shahin; Dadgostar, Haleh; Cherati, Afsaneh Safar; Moghaddam, Ahmad Bagheri; Tabatabaiand, Seyyed Mehdi; Dodaran, Masoud Solaymani

    2013-01-01

    Background: To review a single-surgeon series of 616 athletic patients with anterior cruciate ligament reconstructions in order to evaluate the relationship between the timing of the reconstruction and the incidence of meniscal and chondral injuries. Methods: Six group of patients were categorized based on the time interval from their injury to surgery in the following manner: <3 months, 3-6 months, 6-9 months, 9-18 months, 18-36 months, and >36 months. The presence of meniscal tears was documented and chondral pathology was scored based on the Outerbridge classification. Results: Incidence of medial meniscus tear was significantly higher in patients undergoing reconstruction after 3 months from their injury (P = 0.032). The opportunity of patients with chondral pathology was recorded to be significantly higher in the groups operated on after 6 months from their injuries time (P = 0.008). Conclusions: Considering the effect of time on the rate of having meniscus injury and chondral pathology, reducing the time between the injury and surgery could improve the long-term health outcomes in this population. PMID:23717779

  8. Meniscal fixation with an absorbable staple. An experimental study in dogs.

    PubMed

    Koukoubis, T D; Glisson, R R; Feagin, J A; Seaber, A V; Schenkman, D; Korompilias, A V; Stahl, D L

    1997-01-01

    An absorbable staple for meniscal fixation was developed and evaluated in an in vivo canine study. The staple consisted of two rigid barbed legs, made of a copolymer of polyglycolic acid and polylactic acid, connected by a flexible suture made of the same absorbable material. The staple was developed for arthroscopic use, eliminating the risk of nerve or vascular injuries associated with suture fixation. Eighty-two mongrel dogs underwent meniscal repair in this study, which was performed in two sequential parts. An incision was made in the medial meniscus at the peripheral third and was fixed with either the staple or with a single 3-0 PDS suture. The animals from the first part of the study, in which the biocompatibility of a prototype staple design, was evaluated were sacrificed at 3 days, 2 weeks, 6 weeks, 3 months, and 9 months. Those from the second part of the study, in which an improved staple design of the same material, was evaluated were sacrificed at 6 weeks, 4 months, and 1 year. The operated menisci were either examined histologically or were mechanically tested for tensile strength. Absorption of the staple began by 3 months and was almost complete by 1 year. Mechanically, the staple provided greater tensile strength augmentation of the meniscus than suture fixation for up to 4 months. In the long term, there was no difference between the staple and suture in enhancement of healing. PMID:9127849

  9. The potential of optical coherence tomography in meniscal tear characterization

    NASA Astrophysics Data System (ADS)

    Ling, Hang-yin; Guo, Shuguang; Thieman, Kelley M.; Wise, Brent T.; Pozzi, Antonio; Xie, Huikai; Horodyski, MaryBeth

    2009-02-01

    Meniscal tear is one of the most common knee injuries leading to pain and discomfort. Partial and total meniscectomies have been widely used to treat the avascular meniscal injuries in which tears do not heal spontaneously. However, the meniscectomies would cause an alteration of the tibiofemoral contact mechanics resulting in progressive osteoarthritis (OA). To mitigate the progression of OA, maximal preservation of meniscal tissue is recommended. The clinical challenge is deciding which meniscal tears are amenable to repair and which part of damaged tissues should be removed. Current diagnosis techniques such as arthroscopy and magnetic resonance imaging can provide macrostructural information of menisci, but the microstructural changes that occur prior to the observable meniscal tears cannot be identified by these techniques. Serving as a nondestructive optical biopsy, optical coherence tomography (OCT), a newly developed imaging modality, can provide high resolution, cross-sectional images of tissues and has been shown its capabilty in arthroscopic evaulation of articular cartilage. Our research was to demonstrate the potential of using OCT for nondestructive characterization of the histopathology of different types of meniscal tears from clinical cases in dogs, providing a fundamental understanding of the failure mechanism of meniscal tears. First, cross-sectional images of torn canine menisci obtained from the OCT and scanning electronic microscopy (SEM) were be compared. By studying the organization of collegan fibrils in torn menisci from the SEM images, the feasibility of using OCT to characterize the organization of collegan fibrils was elucidated. Moreover, the crack size of meniscal tears was quantatitively measured from the OCT images. Changes in the crack size of the tear may be useful for understanding the failure mechanism of meniscal tears.

  10. Differential Responses to a Visual Self-Motion Signal in Human Medial Cortical Regions Revealed by Wide-View Stimulation

    PubMed Central

    Wada, Atsushi; Sakano, Yuichi; Ando, Hiroshi

    2016-01-01

    Vision is important for estimating self-motion, which is thought to involve optic-flow processing. Here, we investigated the fMRI response profiles in visual area V6, the precuneus motion area (PcM), and the cingulate sulcus visual area (CSv)—three medial brain regions recently shown to be sensitive to optic-flow. We used wide-view stereoscopic stimulation to induce robust self-motion processing. Stimuli included static, randomly moving, and coherently moving dots (simulating forward self-motion). We varied the stimulus size and the presence of stereoscopic information. A combination of univariate and multi-voxel pattern analyses (MVPA) revealed that fMRI responses in the three regions differed from each other. The univariate analysis identified optic-flow selectivity and an effect of stimulus size in V6, PcM, and CSv, among which only CSv showed a significantly lower response to random motion stimuli compared with static conditions. Furthermore, MVPA revealed an optic-flow specific multi-voxel pattern in the PcM and CSv, where the discrimination of coherent motion from both random motion and static conditions showed above-chance prediction accuracy, but that of random motion from static conditions did not. Additionally, while area V6 successfully classified different stimulus sizes regardless of motion pattern, this classification was only partial in PcM and was absent in CSv. This may reflect the known retinotopic representation in V6 and the absence of such clear visuospatial representation in CSv. We also found significant correlations between the strength of subjective self-motion and univariate activation in all examined regions except for primary visual cortex (V1). This neuro-perceptual correlation was significantly higher for V6, PcM, and CSv when compared with V1, and higher for CSv when compared with the visual motion area hMT+. Our convergent results suggest the significant involvement of CSv in self-motion processing, which may give rise to its

  11. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    SciTech Connect

    Pawelec, K. M. E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E.; Wardale, R. J. E-mail: jw626@cam.ac.uk

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  12. Mechanoreceptors in the Anterior Horn of the Equine Medial Meniscus: an Immunohistochemical Approach.

    PubMed

    Nemery, E; Gabriel, A; Grulke, S; Piret, J; Toppets, V; Antoine, N

    2016-04-01

    Lameness due to stifle and especially meniscal lesions is frequent in equine species. In humans, mechanoreceptors involved in proprioceptive function are well studied. Given the high incidence of meniscal injuries in horses, and the lack of information concerning them in equine menisci, our objective was to study these corpuscles in six healthy anterior horns of the equine medial meniscus, which is the most common localisation reported for equine meniscal injuries. Immunohistochemical stainings were performed using antibodies against high molecular weight neurofilaments and glial fibrillary acidic proteins. From a purely fundamental point of view, our work highlights for the first time the presence of Ruffini, Pacini and Golgi corpuscles in equine meniscus. They were found, isolated or in clusters and always located at the vicinity of blood vessels, at the level of the anterior horn of the equine medial meniscus. This morphological approach could serve as a basis for clinical studies, to evaluate the impact of these corpuscles on the poor sportive prognosis in equine meniscal tears. PMID:25904399

  13. Biomechanical Evaluation of Knee Kinematics after ACL Reconstructions in Anatomic SB and DB - Technique with Additional Medial Meniscus Suture

    PubMed Central

    Lorbach, Olaf; Herbort, Mirco; Engelhardt, Martin; Kieb, Matthias

    2013-01-01

    Objectives: Biomechanical evaluation of knee laxity after single- and double-bundle ACL reconstruction with additional medial meniscus suture. Methods: Kinematics of the intact knee were determined in 12 human cadaver specimens in response to a 134-N anterior tibial load (aTT) and a combined rotatory load of 10 Nm valgus and 4 Nm internal tibial rotation using a robotic/universal force moment sensor testing system. Subsequently, the ACL was resected following the creation of a bucket-handle tear of the medial meniscus. A standard repair of the medial meniscus was performed using 3 inside-out horizontal sutures. Finally, The ACL was reconstructed using an anatomic single-bundle (6) or double-bundle technique (6). Knee kinematics were determined following every sub-step. Results: Significant increase of aTT in the ACL-deficient knee was found with significant increase in the ACL-deficient knee with additional medial meniscal injury (p=.003; p=.009). ACL reconstructions significantly decreased aTT compared to the ACL-deficient knee. No significant differences were found between the intact knee and the ACL reconstructed knee with additional meniscal repair. In response to a simulated pivot shift, aTT in the intact knee significantly increased in the ACL-deficient knee as well as in the meniscus injured/meniscus-sutured knee (p=.003;p=.007). No significant differences were found between the ACL-deficient and ACL reconstructed knee with additional meniscal repair. SB as well as DB ACL reconstruction with additional medial meniscal repair restored knee kinematics compared to the intact knee. Comparison of SB versus DB ACL reconstruction did not reveal any significant differences neither in a simulated Lachman test nor in response to a simulated pivot shift (p=.05). Conclusion: aTT as well as aTT in response to a combined rotatory load significantly increased with ACL deficiency compared to the intact knee, additional medial meniscal injury further increased aTT. Anatomic

  14. 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

  15. Meniscal regeneration with copolymeric collagen scaffolds. In vitro and in vivo studies evaluated clinically, histologically, and biochemically.

    PubMed

    Stone, K R; Rodkey, W G; Webber, R; McKinney, L; Steadman, J R

    1992-01-01

    We sought to create a regeneration template for the meniscal cartilage of the knee to induce complete meniscal regeneration, and to develop the technique for implanting the prosthetic appliance in vivo. We designed a resorbable collagen-based scaffold and conducted in vitro and in vivo studies. In vivo, the scaffold was implanted in the knees of immature swine and mature canines and evaluated clinically, histologically, and biochemically. Because the canine stifle joint meniscus is more clinically relevant to the human meniscus, this paper emphasizes those results. We studied 24 mixed breed dogs (14 males and 10 females) with an average weight of 25.5 kg (range, 20 to 35) that were obtained from a USDA-licensed supplier. The dogs were deemed clinically and radiographically skeletally mature. None of the dogs had a preexisting knee joint abnormality. All dogs underwent an 80% subtotal resection of the medial meniscus bilaterally. A collagen template was implanted in one stifle (N = 24). The contralateral side served as a control: 12 dogs had a total resection alone and the other 12 dogs had an immediate replantation of the autologous meniscus. Results were tabulated at 3, 6, 9, and 12 months. At final evaluation, before the animals were euthanized, the results were submitted for statistical analysis as well as histologic and biochemical analyses. The results demonstrated that a copolymeric collagen-based scaffold can be constructed that is compatible with meniscal fibrochondrocyte growth in vitro and in vivo, that does not inhibit meniscal regeneration in an immature pig, and that may induce regeneration of the meniscus in the mature dog.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1558234

  16. Meniscal replacement using a cryopreserved allograft. An experimental study in the dog.

    PubMed

    Arnoczky, S P; Warren, R F; McDevitt, C A

    1990-03-01

    The medial menisci of 14 adult dogs were replaced using a cryopreserved meniscal allograft. The morphology and metabolic activity of the transplanted allografts were then evaluated using routine histology, a vascular-injection (Spalteholz) technique, and autoroentgenography (Na2(35)SO4 incorporation) at various intervals, from two weeks to six months postoperatively. After transplantation, the allografts retained their normal gross appearance and healed to the capsular tissues of the host by fibrovascular scar tissue. Histologically, the grafts demonstrated a decrease in the number of metabolically active cells after transplantation but had a normal cellular distribution and Na2(35)SO4 uptake by three months. The allografts appeared to function normally after transplantation. Although some degenerative changes were noted in the tibial articular cartilage not covered by the meniscus, the cartilage beneath the allograft appeared normal. PMID:2302876

  17. 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

  18. Arthroscopic Saucerization and Repair of Discoid Lateral Meniscal Tear.

    PubMed

    Fields, Logan K; Caldwell, Paul E

    2015-04-01

    Meniscal tears are among the most commonly diagnosed knee injuries and often require surgical intervention. Understanding the types of meniscal tears and treatment options is paramount to caring for the young athlete. Sports medicine and arthroscopic physicians now recognize that meniscal preservation in the young athlete is essential to the long-term health and function of the knee. Although uncommon, the discoid lateral meniscus is more prone to injury because of its increased thickness and lack of blood supply. Because of the abnormal development, the peripheral attachments are frequently absent and instability often persists after a partial meniscectomy. If the instability is unrecognized during the initial treatment, a recurrence of pain and mechanical symptoms is likely and a subsequent subtotal meniscectomy may be the only treatment option. With increased awareness, arthroscopic saucerization accompanied by arthroscopically assisted inside-out meniscal repair is a preferable treatment option with an excellent outcome. PMID:26052498

  19. Arthroscopic Saucerization and Repair of Discoid Lateral Meniscal Tear

    PubMed Central

    Fields, Logan K.; Caldwell, Paul E.

    2015-01-01

    Meniscal tears are among the most commonly diagnosed knee injuries and often require surgical intervention. Understanding the types of meniscal tears and treatment options is paramount to caring for the young athlete. Sports medicine and arthroscopic physicians now recognize that meniscal preservation in the young athlete is essential to the long-term health and function of the knee. Although uncommon, the discoid lateral meniscus is more prone to injury because of its increased thickness and lack of blood supply. Because of the abnormal development, the peripheral attachments are frequently absent and instability often persists after a partial meniscectomy. If the instability is unrecognized during the initial treatment, a recurrence of pain and mechanical symptoms is likely and a subsequent subtotal meniscectomy may be the only treatment option. With increased awareness, arthroscopic saucerization accompanied by arthroscopically assisted inside-out meniscal repair is a preferable treatment option with an excellent outcome. PMID:26052498

  20. Differential contributions of subregions of medial temporal lobe to memory system in amnestic mild cognitive impairment: insights from fMRI study.

    PubMed

    Chen, Jiu; Duan, Xujun; Shu, Hao; Wang, Zan; Long, Zhiliang; Liu, Duan; Liao, Wenxiang; Shi, Yongmei; Chen, Huafu; Zhang, Zhijun

    2016-01-01

    Altered function of the medial temporal lobe (MTL) is a valuable indicator of conversion from amnestic mild cognitive impairment (aMCI) to Alzheimer's disease. This study is to delineate the functional circuitry of multiple subdivisions of parahippocampal gyrus and hippocampus (HIP) and to examine how this knowledge contributes to a more principled understanding of the contributions of its subregions to memory in aMCI. The functional connectivity (FC) analysis was performed in 85 aMCI and 129 healthy controls. The aMCI demonstrated the distinct disruptive patterns of the MTL subregional connectivity with the whole-brain. The right entorhinal cortex (ERC) and perirhinal cortex (PRC) showed increased connectivity with the left inferior and middle occipital gyrus, respectively, which potentially indicated a compensatory mechanism. Furthermore, the right altered MTL subregional FC was associated with episodic memory performance in aMCI. These results provide novel insights into the heterogeneous nature of its large-scale connectivity in MTL subregions in memory system underlying the memory deficits in aMCI. It further suggests that altered FC of MTL subregions is associated with the impairment of the differential encoding stages of memories and the functional changes in the specific right HIP-ERC-PRC-temporal circuitry may contribute to the impairment of episodic memory in aMCI. PMID:27184985

  1. Differential contributions of subregions of medial temporal lobe to memory system in amnestic mild cognitive impairment: insights from fMRI study

    PubMed Central

    Chen, Jiu; Duan, Xujun; Shu, Hao; Wang, Zan; Long, Zhiliang; Liu, Duan; Liao, Wenxiang; Shi, Yongmei; Chen, Huafu; Zhang, Zhijun

    2016-01-01

    Altered function of the medial temporal lobe (MTL) is a valuable indicator of conversion from amnestic mild cognitive impairment (aMCI) to Alzheimer’s disease. This study is to delineate the functional circuitry of multiple subdivisions of parahippocampal gyrus and hippocampus (HIP) and to examine how this knowledge contributes to a more principled understanding of the contributions of its subregions to memory in aMCI. The functional connectivity (FC) analysis was performed in 85 aMCI and 129 healthy controls. The aMCI demonstrated the distinct disruptive patterns of the MTL subregional connectivity with the whole-brain. The right entorhinal cortex (ERC) and perirhinal cortex (PRC) showed increased connectivity with the left inferior and middle occipital gyrus, respectively, which potentially indicated a compensatory mechanism. Furthermore, the right altered MTL subregional FC was associated with episodic memory performance in aMCI. These results provide novel insights into the heterogeneous nature of its large-scale connectivity in MTL subregions in memory system underlying the memory deficits in aMCI. It further suggests that altered FC of MTL subregions is associated with the impairment of the differential encoding stages of memories and the functional changes in the specific right HIP-ERC-PRC-temporal circuitry may contribute to the impairment of episodic memory in aMCI. PMID:27184985

  2. Diagnosis of ligamentous and meniscal pathologies in patients with anterior cruciate ligament injury: comparison of magnetic resonance imaging and arthroscopic findings

    PubMed Central

    Sayampanathan, Andrew Arjun; Koh, Thean-Howe Bryan; Tan, Hwee-Chye Andrew

    2015-01-01

    Background Magnetic resonance imaging (MRI) is routinely used to diagnose or support clinical diagnoses for meniscal or ligamentous injuries prior to offering patients arthroscopic treatment. However, the sensitivity of MRI for the detection of meniscal injury is not yet 100%. Sportsmen have occasionally returned to play with undiagnosed meniscal lesions on the basis of a normal MRI examination. This study was designed to assess the diagnostic parameters of MRI in patients with acute anterior cruciate ligament (ACL) injury. Methods MRI and arthroscopic findings of 320 patients with acute ACL injury were included in this retrospective review. Patients belonged to a single surgeon from a high volume tertiary healthcare institution. All patients had either a MRI or an arthroscopic diagnosis of an acute ACL injury of one knee or both. All patients underwent therapeutic arthroscopy by the senior author routinely as part of arthroscopy-aided ACL reconstruction. Arthroscopic findings were the diagnostic reference based on which the positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity and concordance strength of association of MRI were calculated for ACL, posterior cruciate ligament (PCL), medial meniscus (MM) and lateral meniscus (LM) injuries. Results MRI was most accurate in diagnosing cruciate ligament injuries with a PPV approaching 100%. The PPV of MRI in diagnosing meniscal injuries was approximately 60%. MRI was almost 100% sensitive and specific in diagnosing ACL injuries and 82% sensitive and 100% specific in diagnosing PCL injuries. Conversely, MRI was 77% sensitive and 90% specific in diagnosing MM injuries; and 57% sensitive and 95% specific in diagnosing LM injuries. Conclusions MRI remains the gold standard for diagnosing soft tissue injuries of the knee. However, there is a false positive rate ranging from 6% to 11% for meniscal tears. PMID:26605289

  3. Outcome of repaired unstable meniscal tears in children and adolescents

    PubMed Central

    2012-01-01

    Background Unstable meniscal tears are rare injuries in skeletally immature patients. Loss of a meniscus increases the risk of subsequent development of degenerative changes in the knee. This study deals with the outcome of intraarticular meniscal repair and factors that affect healing. Parameters of interest were type and location of the tear and also the influence of simultaneous reconstruction of a ruptured ACL. Methods We investigated the outcome of 25 patients (29 menisci) aged 15 (4–17) years who underwent surgery for full thickness meniscal tears, either as isolated lesions or in combination with ACL ruptures. Intraoperative documentation followed the IKDC 2000 standard. Outcome measurements were the Tegner score (pre- and postoperatively) and the Lysholm score (postoperatively) after an average follow-up period of 2.3 years, with postoperative arthroscopy and MRT in some cases. Results 24 of the 29 meniscal lesions healed (defined as giving an asymptomatic patient) regardless of location or type. 4 patients re-ruptured their menisci (all in the pars intermedia) at an average of 15 months after surgery following a new injury. Mean Lysholm score at follow-up was 95, the Tegner score deteriorated, mean preoperative score: 7.8 (4–10); mean postoperative score: 7.2 (4–10). Patients with simultaneous ACL reconstruction had a better outcome. Interpretation All meniscal tears in the skeletally immature patient are amenable to repair. All recurrent meniscal tears in our patients were located in the pars intermedia; the poorer blood supply in this region may give a higher risk of re-rupture. Simultaneous ACL reconstruction appears to benefit the results of meniscal repair. PMID:22616744

  4. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers.

    PubMed

    Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker; Alkjær, Tine; Koblauch, Henrik; Simonsen, Erik Bruun; Helweg-Larsen, Karin; Thygesen, Lau Caspar

    2016-01-01

    Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain, and previous results may be sensitive to reporting and selection bias. We examined the relation between meniscal lesions and cumulative exposure to heavy lifting in a prospective register-based study with complete follow-up and independent information on exposure and outcome. We established a cohort of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time hospital diagnosis or surgery of a meniscal lesion. Baggage handlers had a higher incidence of meniscal lesions than the referents. Within baggage handlers spline regression showed that the incidence rate ratio was 1.91 (95% confidence interval: 1.29-2.84) after five years as a baggage handler and then decreased slowly to reach unity after approximately 30 years, adjusted for effects of potential confounders. This relation between baggage handling and meniscal lesions was present for work on the apron which involves lifting in a kneeling or squatting position, but not in the baggage hall, which only involves lifting in standing positions. The results support that long-term heavy lifting in a kneeling or squatting position is a risk factor for the development of symptomatic

  5. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers

    PubMed Central

    Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker; Alkjær, Tine; Koblauch, Henrik; Simonsen, Erik Bruun; Helweg-Larsen, Karin; Thygesen, Lau Caspar

    2016-01-01

    Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain, and previous results may be sensitive to reporting and selection bias. We examined the relation between meniscal lesions and cumulative exposure to heavy lifting in a prospective register-based study with complete follow-up and independent information on exposure and outcome. We established a cohort of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time hospital diagnosis or surgery of a meniscal lesion. Baggage handlers had a higher incidence of meniscal lesions than the referents. Within baggage handlers spline regression showed that the incidence rate ratio was 1.91 (95% confidence interval: 1.29–2.84) after five years as a baggage handler and then decreased slowly to reach unity after approximately 30 years, adjusted for effects of potential confounders. This relation between baggage handling and meniscal lesions was present for work on the apron which involves lifting in a kneeling or squatting position, but not in the baggage hall, which only involves lifting in standing positions. The results support that long-term heavy lifting in a kneeling or squatting position is a risk factor for the development of symptomatic

  6. Differential methylation of genes in the medial prefrontal cortex of developing and adult rats following exposure to maltreatment or nurturing care during infancy

    PubMed Central

    Blaze, Jennifer; Scheuing, Lisa; Roth, Tania L.

    2013-01-01

    Quality of maternal care in infancy is an important contributing factor in the development of behavior and psychopathology. One way maternal care could affect behavioral trajectories is through environmentally-induced epigenetic alterations within brain regions known to play prominent roles in cognition, emotion regulation, and stress responsivity. Whereas such research has largely focused on the hippocampus or hypothalamus, the prefrontal cortex (PFC) has only begun to receive attention. The current study was designed to determine whether exposure to maltreatment or nurturing care is associated with differential methylation of candidate gene loci (bdnf and reelin) within the medial PFC (mPFC) of developing and adult rats. Using a within-litter design, infant male and female rats were exposed to an adverse or nurturing caregiving environment outside their homecage for 30 minutes per day during the first postnatal week. Additional littermates remained with their biological caregiver within the homecage during the manipulations. We observed that infant rats subjected to caregiver maltreatment emitted more audible and ultrasonic vocalizations than littermates subjected to nurturing care either within or outside of the homecage. While we found no maltreatment-induced changes in bdnf DNA methylation present in infancy, sex-specific alterations were present in the mPFC of adolescents and adults that had been exposed to maltreatment. Furthermore, while maltreated-females showed differences in reelin DNA methylation that were transient, males exposed to maltreatment and both males and females exposed to nurturing care outside the homecage showed differences in reelin methylation that emerged by adulthood. Our results demonstrate the ability of infant-caregiver interactions to epigenetically mark genes known to play a prominent role in cognition and psychiatric disorders within the mPFC. Furthermore, our data indicate the remarkable complexity of alterations that can occur

  7. Growth differentiation factor-15 promotes glutamate release in medial prefrontal cortex of mice through upregulation of T-type calcium channels

    PubMed Central

    Liu, Dong-Dong; Lu, Jun-Mei; Zhao, Qian-Ru; Hu, Changlong; Mei, Yan-Ai

    2016-01-01

    Growth differentiation factor-15 (GDF-15) has been implicated in ischemic brain injury and synapse development, but its involvement in modulating neuronal excitability and synaptic transmission remain poorly understood. In this study, we investigated the effects of GDF-15 on non-evoked miniature excitatory post-synaptic currents (mEPSCs) and neurotransmitter release in the medial prefrontal cortex (mPFC) in mice. Incubation of mPFC slices with GDF-15 for 60 min significantly increased the frequency of mEPSCs without effect on their amplitude. GDF-15 also significantly elevated presynaptic glutamate release, as shown by HPLC. These effects were blocked by dual TGF-β type I receptor (TβRI) and TGF-β type II receptor (TβRII) antagonists, but not by a TβRI antagonist alone. Meanwhile, GDF-15 enhanced pERK level, and inhibition of MAPK/ERK activity attenuated the GDF-15-induced increases in mEPSC and glutamate release. Blocking T-type calcium channels reduced the GDF-15 induced up-regulation of synaptic transmission. Membrane-protein extraction and use of an intracellular protein-transport inhibitor showed that GDF-15 promoted CaV3.1 and CaV3.3 α-subunit expression by trafficking to the membrane. These results confirm previous findings in cerebellar granule neurons, in which GDF-15 induces its neurobiological effects via TβRII and activation of the ERK pathway, providing novel insights into the mechanism of GDF-15 function in cortical neurons. PMID:27353765

  8. Treatment of meniscal tears: An evidence based approach

    PubMed Central

    Mordecai, Simon C; Al-Hadithy, Nawfal; Ware, Howard E; Gupte, Chinmay M

    2014-01-01

    Treatment options for meniscal tears fall into three broad categories; non-operative, meniscectomy or meniscal repair. Selecting the most appropriate treatment for a given patient involves both patient factors (e.g., age, co-morbidities and compliance) and tear characteristics (e.g., location of tear/age/reducibility of tear). There is evidence suggesting that degenerative tears in older patients without mechanical symptoms can be effectively treated non-operatively with a structured physical therapy programme as a first line. Even if these patients later require meniscectomy they will still achieve similar functional outcomes than if they had initially been treated surgically. Partial meniscectomy is suitable for symptomatic tears not amenable to repair, and can still preserve meniscal function especially when the peripheral meniscal rim is intact. Meniscal repair shows 80% success at 2 years and is more suitable in younger patients with reducible tears that are peripheral (e.g., nearer the capsular attachment) and horizontal or longitudinal in nature. However, careful patient selection and repair technique is required with good compliance to post-operative rehabilitation, which often consists of bracing and non-weight bearing for 4-6 wk. PMID:25035825

  9. The association of meniscal status, lower extremity alignment, and body mass index with chondrosis at the time of revision Anterior Cruciate Ligament reconstruction

    PubMed Central

    Brophy, Robert H.; Haas, Amanda K.; Huston, Laura J.; Nwosu, Sam K.; Wright, Rick W.

    2015-01-01

    Background Knees undergoing revision ACL reconstruction (rACLR) have a high prevalence of articular cartilage lesions. Hypothesis The purpose of this study was to test the hypothesis that the prevalence of chondrosis at the time of rACLR is associated with meniscus status and lower extremity alignment. Study design Cross sectional study. Methods Data from the prospective Multicenter ACL Revision Study (MARS) cohort was reviewed to identify patients with pre-operative lower extremity alignment films. Lower extremity alignment was defined by the weight bearing line (WBL) as a percentage of the tibial plateau width, while the chondral and meniscal status of each weight bearing compartment was recorded at the time of surgery. Multivariable proportional odds models were constructed and adjusted for relevant factors in order to examine which risk factors were independently associated with the degree of medial and lateral compartment chondrosis. Results The cohort included 246 patients with lower extremity alignment films at the time of rACLR. Average (SD) patient age was 26.9 (9.5) years with a BMI of 26.4 (4.6). The medial compartment had more chondrosis (Grade 2/3: 42%, Grade 4: 6.5%) than the lateral compartment (Grade 2/3: 26%, Grade 4: 6.5%). Disruption of the meniscus was noted in 35% of patients on the medial side and 16% in the lateral side. The average (SD) WBL was measured to be 0.43 (0.13). Medial compartment chondrosis was associated with BMI (p=0.025), alignment (p=0.002), and medial meniscus status (p=0.001). None of the knees with the WBL lateral to 0.625 had Grade 4 chondrosis in the medial compartment. Lateral compartment chondrosis was significantly associated with age (p=0.013) and lateral meniscus status (p<0.001). Subjects with ‘intact’ menisci were found to decrease their odds of having chondrosis by 64–84%. Conclusions The status of articular cartilage in the tibiofemoral compartments at the time of rACLR is related to meniscal status. Lower

  10. The use of PRP in ligament and meniscal healing.

    PubMed

    Braun, Hillary J; Wasterlain, Amy S; Dragoo, Jason L

    2013-12-01

    Platelet-rich plasma (PRP) has become a popular treatment for acute and chronic soft tissue injuries. Although the majority of research has focused on its use in tendinopathy, PRP may have potential in meniscus and ligament healing. Some level II studies support a possible benefit for anterior cruciate ligament (ACL) allograft maturation, and preliminary animal studies point to a potential role for PRP in primary ACL repair. However, randomized controlled trials have not demonstrated a benefit of PRP for ACL tendon allograft-tunnel integration. To date, 2 studies document the use of PRP for meniscal applications, but this field is largely unexplored. With respect to ligament and meniscal applications, the current literature suggests PRP may be promising for primary ACL repair in skeletally immature patients, ACL graft maturation, and repair of meniscal tears in the avascular zone. PMID:24212368

  11. Regeneration of meniscal cartilage with use of a collagen scaffold. Analysis of preliminary data.

    PubMed

    Stone, K R; Steadman, J R; Rodkey, W G; Li, S T

    1997-12-01

    A collagen scaffold was designed for use as a template for the regeneration of meniscal cartilage and was tested in ten patients in an initial, Food and Drug Administration-approved, clinical feasibility trial. The goal of the study was to evaluate the implantability and safety of the scaffold as well as its ability to support tissue ingrowth. The study was based on the findings of in vitro and in vivo investigations in dogs that had demonstrated cellular ingrowth and tissue regeneration through the scaffold. Nine patients remained in the study for at least thirty-six months, and one patient voluntarily withdrew after three months for personal reasons. The collagen scaffold was found to be implantable and to be safe over the three-year period. Histologically, it supported regeneration of tissue in meniscal defects of various sizes. No adverse immunological reactions were noted on sequential serological testing. On second-look arthroscopy, performed either three or six months after implantation, gross and histological evaluation revealed newly formed tissue replacing the implant as it was resorbed. At thirty-six months, the nine patients reported a decrease in the symptoms. According to a scale that assigned 1 point for strenuous activity and 5 points for an inability to perform sports activity, the average score was 1.5 points before the injury, 3.0 points after the injury and before the operation, and 2.4 points at six months postoperatively, 2.2 points at twelve months, 2.0 points at twenty-four months, and 1.9 points at thirty-six months. According to a scale that assigned 0 points for no pain and 3 points for severe pain, the average pain score was 2.2 points preoperatively and 0.6 point thirty-six months postoperatively. One patient, who had had a repair of a bucket-handle tear of the medial meniscus and augmentation with the collagen scaffold, had retearing of the cartilage nineteen months after implantation. Another patient had debridement because of an

  12. Arthroscopic Meniscal Allograft Transplantation With Soft-Tissue Fixation Through Bone Tunnels

    PubMed Central

    Spalding, Tim; Parkinson, Ben; Smith, Nick A.; Verdonk, Peter

    2015-01-01

    Meniscal allograft transplantation improves clinical outcomes for patients with symptomatic meniscus-deficient knees. We describe an established arthroscopic technique for meniscal allograft transplantation without the need for bone fixation of the meniscal horns. After preparation of the meniscal bed, the meniscus is parachuted into the knee through a silicone cannula and the meniscal horns are fixed with sutures through bone tunnels. The body of the meniscus is then fixed with a combination of all-inside and inside-out sutures. This technique is reliable and reproducible and has clinical outcomes comparable with those of bone plug fixation techniques. PMID:26900554

  13. Arthroscopic Meniscal Allograft Transplantation With Soft-Tissue Fixation Through Bone Tunnels.

    PubMed

    Spalding, Tim; Parkinson, Ben; Smith, Nick A; Verdonk, Peter

    2015-10-01

    Meniscal allograft transplantation improves clinical outcomes for patients with symptomatic meniscus-deficient knees. We describe an established arthroscopic technique for meniscal allograft transplantation without the need for bone fixation of the meniscal horns. After preparation of the meniscal bed, the meniscus is parachuted into the knee through a silicone cannula and the meniscal horns are fixed with sutures through bone tunnels. The body of the meniscus is then fixed with a combination of all-inside and inside-out sutures. This technique is reliable and reproducible and has clinical outcomes comparable with those of bone plug fixation techniques. PMID:26900554

  14. Advances and Prospects in Tissue-Engineered Meniscal Scaffolds for Meniscus Regeneration

    PubMed Central

    Guo, Weimin; Liu, Shuyun; Zhu, Yun; Yu, Changlong; Lu, Shibi; Yuan, Mei; Gao, Yue; Huang, Jingxiang; Yuan, Zhiguo; Peng, Jiang; Wang, Aiyuan; Wang, Yu; Chen, Jifeng; Zhang, Li; Sui, Xiang; Xu, Wenjing; Guo, Quanyi

    2015-01-01

    The meniscus plays a crucial role in maintaining knee joint homoeostasis. Meniscal lesions are relatively common in the knee joint and are typically categorized into various types. However, it is difficult for inner avascular meniscal lesions to self-heal. Untreated meniscal lesions lead to meniscal extrusions in the long-term and gradually trigger the development of knee osteoarthritis (OA). The relationship between meniscal lesions and knee OA is complex. Partial meniscectomy, which is the primary method to treat a meniscal injury, only relieves short-term pain; however, it does not prevent the development of knee OA. Similarly, other current therapeutic strategies have intrinsic limitations in clinical practice. Tissue engineering technology will probably address this challenge by reconstructing a meniscus possessing an integrated configuration with competent biomechanical capacity. This review describes normal structure and biomechanical characteristics of the meniscus, discusses the relationship between meniscal lesions and knee OA, and summarizes the classifications and corresponding treatment strategies for meniscal lesions to understand meniscal regeneration from physiological and pathological perspectives. Last, we present current advances in meniscal scaffolds and provide a number of prospects that will potentially benefit the development of meniscal regeneration methods. PMID:26199629

  15. Meniscal tears in the ACL-deficient knee: correlation between meniscal tears and the timing of ACL reconstruction.

    PubMed

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Mikalef, Petros; Ziogas, Evangelos; Voulgaropoulos, Harilaos

    2007-12-01

    Despite the fact that anterior cruciate ligament reconstruction (ACLR) is a common procedure, no clear guideline regarding the timing of reconstruction has been established. We hypothesized that there is a point in post injury period, after which significant increase in meniscal tears occurs. The purpose of this study was to derive a guideline in order to reduce the rate of secondary meniscal tears in the ACL-deficient knee. A total of 451 patients were retrospectively studied and divided into six groups according to the time from injury to ACLR: (a) 105 patients had undergone ACLR within 1.5 months post injury, (b) 93 patients within 1.5-3 months, (c) 72 patients within fourth to sixth month, (d) 56 patients within seventh to twelfth month, (e) 45 patients within the second year and (f) 80 patients within the third to fifth year. The presence of meniscal tears was noted at the time of ACL reconstruction and then recorded and statistically analysed. Fifty-three (50.5%) patients from group a, 46 (49.5%) from group b, 39 (54.2%) from group c, 31 (68.9%) from group d, 28 (62.2%) from group e and 54 (67.5%) from group f had meniscal tear requiring treatment. The statistical analysis demonstrated that the earliest point of significantly higher incidence of meniscal tears was in patients undergoing ACLR more than 3 months post injury. Therefore, ACLR should be carried out within the first 3 months post injury in order to minimise the risk of secondary meniscal tears. PMID:17899001

  16. Glutaraldehyde-cross-linked meniscal allografts: clinical, gross, and histological results.

    PubMed

    Powers, D L; Davenport, M E; Wisnewski, P J

    1988-01-01

    Osteoarthritic changes in the knee are often a late result of total meniscectomy. In cases of total resection, availability of a prosthetic meniscus might limit development of these changes. The objective of this research was to evaluate a glutaraldehyde-cross-linked medial meniscus as a morphologically and biologically compatible prosthesis in a canine model. Medial and lateral menisci were harvested from donor dogs, frozen in saline, and cross-linked with glutaraldehyde. Five host animals were selected and matched with donors. Glutaraldehyde-cross-linked medial menisci were implanted bilaterally in the stifle joints and one glutaraldehyde cross-linked lateral meniscus was implanted subcutaneously. Clinical results showed asymptomatic limb and joint usage during the 12 postoperative weeks. Gross and histological evaluations indicated acceptable biocompatibility. The subcutaneous implants were encapsulated with a thin fibrous tissue capsule that was only mildly inflamed. Within the joints, the anterior attachment and periphery were maintained in position by their sutures; however, there was dehiscence of the posterior suture in all cases. The articulating surfaces of the implants were intact. There was an initial loss in the quantity of proteoglycans following glutaraldehyde treatment, with significant recovery after implantation into the joints. There were significant degenerative changes (loss of proteoglycans and fibrillation) in the articular cartilage on the femoral condyle and tibial plateau most likely a result of the posterior attachment failure. It was concluded that glutaraldehyde-cross-linked meniscal allografts showed an acceptable degree of histocompatibility. However, failure of the posterior attachment interfered with testing the efficacy of the prosthesis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3155294

  17. Glutamate Receptor Antagonist Infusions into the Basolateral and Medial Amygdala Reveal Differential Contributions to Olfactory vs. Context Fear Conditioning and Expression

    ERIC Educational Resources Information Center

    Walker, David L.; Paschall, Gayla Y.; Davis, Michael

    2005-01-01

    The basolateral amygdala's involvement in fear acquisition and expression to visual and auditory stimuli is well known. The involvement of the basolateral and other amygdala areas in fear acquisition and expression to stimuli of other modalities is less certain. We evaluated the contribution of the basolateral and medial amygdala to olfactory and…

  18. NR2A- and NR2B-Containing NMDA Receptors in the Prelimbic Medial Prefrontal Cortex Differentially Mediate Trace, Delay, and Contextual Fear Conditioning

    ERIC Educational Resources Information Center

    Gilmartin, Marieke R.; Kwapis, Janine L.; Helmstetter, Fred J.

    2013-01-01

    Activation of "N"-methyl-D-aspartate receptors (NMDAR) in the prelimbic medial prefrontal cortex (PL mPFC) is necessary for the acquisition of both trace and contextual fear memories, but it is not known how specific NR2 subunits support each association. The NR2B subunit confers unique properties to the NMDAR and may differentially…

  19. Anomalous insertion of the medial meniscus into the anterior cruciate ligament: the MR appearance.

    PubMed

    Cha, J-G; Min, K-D; Han, J-K; Hong, H-S; Park, S-J; Park, J-S; Paik, S-H

    2008-01-01

    The aim of this study was to determine the characteristic MR findings of the anomalous insertion of the medial meniscus (AIMM) into the anterior cruciate ligament (ACL), and to document potential pitfalls in its interpretation. We reviewed 1326 consecutive knee arthroscopic studies to identify patients with an AIMM. 30 knees of 26 patients (4 females, 22 males; average age, 31.3 years; range, 14-50 years) were included in this study. We evaluated the presence of an AIMM and analysed the MR findings, including the ACL attachment sites of the AIMMs, the absence of the transverse ligament, meniscal tears and a discoid meniscus. AIMMs were detected by MR imaging in 16 knees of 18 patients (60%, 18/30). The AIMMs showed a linear band with low signal intensity on T2 weighted sagittal images running parallel to the ACL. The AIMMs were inserted into the lower portion of the ACL in eight knees, the middle portion in five knees, and the intercondylar notch in five knees. Meniscal tears (10 medial, 10 lateral) were found in 20 knees of 16 patients. Six knees of five patients showed a discoid meniscus. 15 knees of 14 patients showed no transverse ligament on MR imaging. An AIMM has the potential to be misinterpreted as a meniscal tear, ACL tear or infrapatellar plica on knee MR imaging. Familiarity with the characteristic MR findings can aid in the detection of an AIMM into the ACL. PMID:17971476

  20. Diagnostic performance of 3D TSE MRI versus 2D TSE MRI of the knee at 1.5 T, with prompt arthroscopic correlation, in the detection of meniscal and cruciate ligament tears*

    PubMed Central

    Chagas-Neto, Francisco Abaeté; Nogueira-Barbosa, Marcello Henrique; Lorenzato, Mário Müller; Salim, Rodrigo; Kfuri-Junior, Maurício; Crema, Michel Daoud

    2016-01-01

    Objective To compare the diagnostic performance of the three-dimensional turbo spin-echo (3D TSE) magnetic resonance imaging (MRI) technique with the performance of the standard two-dimensional turbo spin-echo (2D TSE) protocol at 1.5 T, in the detection of meniscal and ligament tears. Materials and Methods Thirty-eight patients were imaged twice, first with a standard multiplanar 2D TSE MR technique, and then with a 3D TSE technique, both in the same 1.5 T MRI scanner. The patients underwent knee arthroscopy within the first three days after the MRI. Using arthroscopy as the reference standard, we determined the diagnostic performance and agreement. Results For detecting anterior cruciate ligament tears, the 3D TSE and routine 2D TSE techniques showed similar values for sensitivity (93% and 93%, respectively) and specificity (80% and 85%, respectively). For detecting medial meniscal tears, the two techniques also had similar sensitivity (85% and 83%, respectively) and specificity (68% and 71%, respectively). In addition, for detecting lateral meniscal tears, the two techniques had similar sensitivity (58% and 54%, respectively) and specificity (82% and 92%, respectively). There was a substantial to almost perfect intraobserver and interobserver agreement when comparing the readings for both techniques. Conclusion The 3D TSE technique has a diagnostic performance similar to that of the routine 2D TSE protocol for detecting meniscal and anterior cruciate ligament tears at 1.5 T, with the advantage of faster acquisition. PMID:27141127

  1. Cranial cruciate ligament repair in dogs with and without meniscal lesions treated by different minimally invasive methods.

    PubMed

    Ertelt, J; Fehr, M

    2009-01-01

    The goal of this study was to evaluate different minimally invasive surgical options as therapy for cranial cruciate ligament rupture and resulting meniscal injuries. In this study, 81 stifle joints of dogs with complete or partial rupture of the cranial cruciate ligament were treated with minimally invasive surgery at the Small Animal Clinic of the University of Veterinary Medicine in Hannover. The patients were divided into three groups depending on intraoperative diagnosis and the surgical technique applied. The dogs in group I (n = 26) had an isolated rupture of the cranial cruciate ligament (CCLR), while those in groups II (n = 26) and III (n = 29) also had an injury of the medial meniscus. Resection of the damaged meniscal part was performed by arthroscopically guided partial meniscectomy (AGPM) on the dogs in group II, while minimally invasive medial arthrotomy (MIMA) was used on the dogs of group III. All of the stifles were stabilized with a modified lateral imbrication technique using a braided, synthetic, absorbable suture material (Panacryl). Six months after surgery 76.5% of all patients were examined clinically and 74.1% radiographically for evaluation of the success of the different treatment techniques. At this examination, there were no signs of lameness in 42.1% of group I (CCLR), 65.0% of group II (AGPM) and 87.0% of group III (MIMA). Upon palpation, 75.8% of these stifle joints were found to be stable. Radiographic evaluations did not show any indication of progression of gonarthrosis in 73.3% of all stifle joints examined here. PMID:19151866

  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. The sensitivity of cartilage contact pressures in the knee joint to the size and shape of an anatomically shaped meniscal implant.

    PubMed

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

    2015-06-01

    Since meniscal geometry affects the cartilage contact pressures, it is essential to carefully define the geometry of the synthetic meniscal implant that we developed. Recently, six independent modes of size- and shape-related geometry variation were identified through 3D statistical shape modeling (SSM) of the medial meniscus. However, this model did not provide information on the functional importance of these geometry characteristics. Therefore, in this study finite element simulations were performed to determine the influence of anatomically-based meniscal implant size and shape variations on knee cartilage contact pressures. Finite element simulations of the knee joint were performed for a total medial meniscectomy, an allograft, the average implant geometry, six implant sizes and ten shape variations. The geometries of the allograft and all implant variations were based on the meniscus SSM. Cartilage contact pressures and implant tensile strains were evaluated in full extension under 1200N of axial compression. The average implant induced cartilage peak pressures intermediate between the allograft and meniscectomy and also reduced the cartilage area subjected to pressures >5MPa compared to the meniscectomy. The smaller implant sizes resulted in lower cartilage peak pressures and compressive strains than the allograft, yet high implant tensile strains were observed. Shape modes 2, 3 and 6 affected the cartilage contact stresses but to a lesser extent than the size variations. Shape modes 4 and 5 did not result in changes of the cartilage stress levels. The present study indicates that cartilage contact mechanics are more sensitive to implant size than to implant shape. Down-sizing the implant resulted in more favorable contact mechanics, but caused excessive material strains. Further evaluations are necessary to balance cartilage contact pressures and material strains to ensure cartilage protection and longevity of the implant. PMID:25766390

  4. Meniscal repair using a flap of synovium. An experimental study in the dog.

    PubMed

    Kobuna, Y; Shirakura, K; Niijima, M

    1995-01-01

    The healing process of longitudinal lesions in the avascular region of the meniscus was investigated in 42 menisci from 21 dogs. A longitudinal incision was made in the avascular portion of the medial menisci of 21 dogs. In one knee, a flap of synovium was sutured into the wound, and in the other, the wound was sutured as a control. Animals were killed after 1 to 12 weeks, and the menisci were removed and examined by gross inspection, light microscopy, and microangiography. In the control knees, no healing had occurred. In 19 of 21 knees in which a synovial pedicle was used, the suture site did not open at any of the postoperative weeks. The longitudinal lesion was repaired with fibrovascular tissue at 6 weeks, and the vessels over the femoral surface of the menisci and an inner portion of the menisci had reached the suture site. The healing of meniscal lesion occurred due to the use of the vascularized synovial pedicle flap and the neovascularization from the parameniscal area. PMID:7634014

  5. Automatic CAD of meniscal tears on MR imaging: a morphology-based approach

    NASA Astrophysics Data System (ADS)

    Ramakrishna, Bharath; Liu, Weimin; Safdar, Nabile; Siddiqui, Khan; Kim, Woojin; Juluru, Krishna; Chang, Chein-I.; Siegel, Eliot

    2007-03-01

    Knee-related injuries, including meniscal tears, are common in young athletes and require accurate diagnosis and appropriate surgical intervention. Although with proper technique and skill, confidence in the detection of meniscal tears should be high, this task continues to be a challenge for many inexperienced radiologists. The purpose of our study was to automate detection of meniscal tears of the knee using a computer-aided detection (CAD) algorithm. Automated segmentation of the sagittal T1-weighted MR imaging sequences of the knee in 28 patients with diagnoses of meniscal tears was performed using morphologic image processing in a 3-step process including cropping, thresholding, and application of morphological constraints. After meniscal segmentation, abnormal linear meniscal signal was extracted through a second thresholding process. The results of this process were validated by comparison with the interpretations of 2 board-certified musculoskeletal radiologists. The automated meniscal extraction algorithm process was able to successfully perform region of interest selection, thresholding, and object shape constraint tasks to produce a convex image isolating the menisci in more than 69% of the 28 cases. A high correlation was also noted between the CAD algorithm and human observer results in identification of complex meniscal tears. Our initial investigation indicates considerable promise for automatic detection of simple and complex meniscal tears of the knee using the CAD algorithm. This observation poses interesting possibilities for increasing radiologist productivity and confidence, improving patient outcomes, and applying more sophisticated CAD algorithms to orthopedic imaging tasks.

  6. Meniscal tears and discoid meniscus in children: diagnosis and treatment.

    PubMed

    Kramer, Dennis E; Micheli, Lyle J

    2009-11-01

    The incidence of traumatic meniscal tears in children is on the rise, likely because of increased sports participation and more accurate diagnostic modalities. The increased vascularity of the developing meniscus is believed to enable greater healing potential. Meniscal tears in children are often amenable to repair, and excellent clinical results have been reported. Knee size must be considered when determining the optimal method of repair. Discoid menisci represent a spectrum of morphologic abnormalities and instability of the lateral meniscus. Highly unstable variants often present with the classic "snapping knee syndrome," whereas stable variants may remain asymptomatic until a tear develops. Asymptomatic discoid menisci should be observed, whereas symptomatic discoid menisci are best treated with saucerization and repair. Early to midterm reports on saucerization and repair of discoid lateral meniscus in children are promising. PMID:19880680

  7. All-inside arthroscopic suturing technique for meniscal ruptures.

    PubMed

    Darabos, Nikica; Dovzak-Bajs, Ivana; Bilić, Vide; Darabos, Anela; Popović, Iva; Cengić, Tomislav

    2012-03-01

    The most frequent indication for surgical treatment of the knee is lesion of the meniscus. The "all inside" arthroscopic technique with bioresorptive material for meniscus lesion is becoming the most popular treatment. This prospective study included 10 patients with posterior meniscal horn lesion operatively treated at Sports Traumatology Department. The "all inside" technique was performed by intra-articular application of bioresorptive pins-Darts sticks or Meniscus Viper and bioresorptive string. Patients were followed up for 2-6 months postoperatively and graded according to the IKDC 2000 scale. All surgical treatments showed satisfactory results. Young patients with acute longitudinal peripheral lesion-posterior horn lesions, in the red-red or red-white meniscal zone, 1-2 centimeters long are most appropriate for this type of treatment. In these patients, this technique proved to be superior and free from the risk of neurovascular damage. For better authentication of this conclusion, additional prospective randomized studies should be performed. PMID:22920001

  8. Chondromatosis within a meniscal cyst of the knee.

    PubMed

    Hasegawa, Y; Ishimura, M; Tamai, S; Fujisawa, Y

    1995-02-01

    A 32-year-old man complained of left gonalgia for 2 years and noticed a soft part tumor on the lateral side of his left knee. Roentgenograms showed some small calcified shadows at the same site of the tumor. Arthroscopy revealed a lateral meniscus to be an incomplete discoid with degenerative tears. At the operation, a multilocular soft part tumor was noticed in continuity with the lateral meniscus macroscopically. Small, loose bodies and gelatinous fluid were found in the cavity of the tumor. Histologically loose bodies were chondroma and the soft part tumor was meniscal cyst. The meniscal cyst wall contained hyaline cartilagenous tissue. Therefore it was thought that chondroma originated from the cyst wall. PMID:7727004

  9. 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

  10. Osteochondral and Meniscal Allograft Transplantation in the Football (Soccer) Player

    PubMed Central

    Williams, Riley J.; Gersoff, Wayne K.; Bugbee, William D.

    2012-01-01

    Knee injuries are common in football, frequently involving damage to the meniscus and articular cartilage. These injuries can cause significant disability, result in loss of playing time, and predispose players to osteoarthritis. Osteochondral allografting is an increasingly popular treatment option for osteoarticular lesions in athletes. Osteochondral allografts provide mature, orthotopic hyaline cartilage on an osseous scaffold that serves as an attachment vehicle, which is rapidly replaced via creeping substitution, leading to reliable graft integration that allows for simplified rehabilitation and accelerated return to sport. The indications for meniscal replacement in football players are currently still evolving. Meniscus allografts offer potential functional, analgesic, and chondroprotective benefits in the meniscectomized knee. In the player at the end of his or her professional/competitive career, meniscal allografts can play a role in averting progression of chondropenia and facilitating knee function and an active lifestyle. This article is intended to present a concise overview of the limited published results for osteochondral and meniscal allografting in the athletic population and to provide a practical treatment algorithm that is of relevance to the clinician as well as the patient/football player, based on current consensus of opinion. PMID:26069605

  11. Meniscal allograft transplantation: preoperative assessment, surgical considerations, and clinical outcomes.

    PubMed

    Mascarenhas, Randy; Yanke, Adam B; Frank, Rachel M; Butty, Davietta C; Cole, Brian J

    2014-12-01

    The purpose of this review is to characterize the preoperative assessment of meniscal allograft transplantation (MAT) candidates, to detail MAT surgical techniques, and to evaluate current clinical outcome data on MAT. The MAT candidate is typically less than 50 years old and has a history of knee injury, previous meniscus surgery, and persistent pain. Physical exam generally reveals knee pain with joint line tenderness with normal radiographs and magnetic resonance imaging demonstrating the postmeniscectomized state. There are several common surgical techniques used for transplantation, with fixation achieved through sutures, bony fixation, or a combination of the two. Concomitant procedures such as anterior cruciate ligament reconstruction, osteotomy, and other cartilage procedures are commonly performed. The available short- and long-term studies of clinical outcomes of MAT are variable and difficult to effectively compare due to heterogeneity of the study population and available treatment techniques. In addition, there are no published randomized controlled trials. However, recent reviews and cohort studies of clinical outcomes following MAT have shown that whether performed in isolation or performed with concomitant articular cartilage, realignment, or soft tissue reconstruction procedures MAT outcomes have been acceptable with the majority of studies reporting improved clinical outcomes regardless of the scoring system employed. MAT has proven to be a safe and effective technique in reducing knee pain and improving function in the symptomatic meniscal deficient knee. Evaluation of long-term clinical outcomes is necessary as is evaluation of meniscal replacement alternatives. PMID:24951950

  12. Meniscal Allograft Transplantation A Comprehensive Historical and Current Review.

    PubMed

    Hannon, Michael G; Ryan, Michael K; Strauss, Eric J

    2015-06-01

    Throughout the history of orthopaedics, our understanding of the function and necessity of the meniscus has significantly evolved, and with it, our techniques of treating, repairing, preserving, and replacing it have progressed in parallel. Currently, it is known that a meniscus deficiency is a predisposing factor to the development of degenerative changes of the knee. Thus, it is incumbent upon the surgeon to preserve the meniscus to the extent that biology will allow. Unfortunately, circumstances arise when the meniscus cannot be preserved, and young patients afflicted by irreparable meniscus deficiency may be potential candidates for a meniscus transplant. Though its indications are limited and its execution technically complex, meniscal allograft transplant has been shown to provide good subjective outcomes and is a potentially joint preserving surgery. This paper provides a comprehensive and historical review of the meniscus, a brief review of meniscus anatomy and biomechanics, and commentary on the role of meniscal allograft transplant for the treatment of meniscal deficiency, including patient selection, graft selection and sizing, surgical technique, and outcomes. PMID:26517162

  13. PHYSICAL EXAMINATIONS FOR DIAGNOSING MENISCAL INJURIES: CORRELATION WITH SURGICAL FINDINGS

    PubMed Central

    Gobbo, Ricardo da Rocha; Rangel, Victor de Oliveira; Karam, Francisco Consoli; Pires, Luiz Antônio Simões

    2015-01-01

    Objective: A set of five maneuvers for meniscal injuries (McMurray, Apley, Childress and Steinmann 1 and 2) was evaluated and their sensitivity, specificity, accuracy and likelihood were calculated. The same methods were applied to each test individually. Methods: One hundred and fifty-two patients of both sexes who were going to undergo videoarthroscopy on the knee were examined blindly by one of five residents at this hospital, without knowledge of the clinical data and why the patient was going to undergo an operation. This examination was conducted immediately before the videoarthroscopy and its results were recorded in an electronic spreadsheet. The set of maneuvers was considered positive when one was positive. In the individual analysis, it was enough for the test to be positive. Results: The analysis showed that the set of five meniscal tests presented sensitivity of 89%, specificity of 42%, accuracy of 75%, positive likelihood of 1.53 and negative likelihood of 0.26. Individually, the tests presented accuracy of between 48% and 53%. Conclusion: The set of maneuvers for meniscal injuries presented a good accuracy and significant value, especially for ruling out injury. Individually, the tests had less diagnostic value, although the Apley test had better specificity. PMID:27047833

  14. Structured three-dimensional co-culture of mesenchymal stem cells with meniscus cells promotes meniscal phenotype without hypertrophy.

    PubMed

    Cui, Xiaofeng; Hasegawa, Akihiko; Lotz, Martin; D'Lima, Darryl

    2012-09-01

    Menisci play a crucial role in weight distribution, load bearing, shock absorption, lubrication, and nutrition of articular cartilage within the knee joint. Damage to the meniscus typically does not heal spontaneously due to its partial avascular nature. Partial or complete meniscectomy is a common clinical treatment of the defective meniscus. However, this procedure ultimately leads to osteoarthritis due to increased mechanical stress to the articular cartilage. Meniscus tissue engineering offers a promising solution for partial or complete meniscus deficiency. Mesenchymal stem cells (MSC) have the potential to differentiate into meniscal fibrochondrocyte as well as deliver trophic effects to the differentiated cells. This study tested the feasibility of using MSC co-cultured with mature meniscal cells (MC) for meniscus tissue engineering. Structured cell pellets were created using MC and MSC at varying ratios (100:0, 75:25, 50:50, 25:75, and 0:100) and cultured with or without transforming growth factor-beta 3 supplemented chondrogenic media for 21 days. The meniscal and hypertrophic gene expression, gross appearance and structure of the pellets, meniscus extracellular matrix (ECM), histology and immunohistochemistry of proteoglycan and collagen were evaluated. Co-culture of MC with MSC at 75:25 demonstrated highest levels of collagen type I and glycosaminoglycans (GAG) production, as well as the lowest levels of hypertrophic genes, such as COL10A1 and MMP13. All co-culture conditions showed better meniscus ECM production and hypertrophic inhibition as compared to MSC culture alone. The collagen fiber bundles observed in the co-cultures are important to produce heterogenic ECM structure of meniscus. In conclusion, co-culturing MC and MSC is a feasible and efficient approach to engineer meniscus tissue with enhanced ECM production without hypertrophy. PMID:22422555

  15. 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)

  16. 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

  17. Differential relationships between D1 and D2 dopamine receptor expression in the medial preoptic nucleus and sexually-motivated song in male European starlings (Sturnus vulgaris).

    PubMed

    DeVries, M S; Cordes, M A; Stevenson, S A; Riters, L V

    2015-08-20

    Converging data in songbirds support a central role for the medial preoptic nucleus (POM) in motivational aspects of vocal production. Recent data suggest that dopamine in the POM plays a complex modulatory role in the production of sexually-motivated song and that an optimal level of dopamine D1 receptor stimulation is required to facilitate singing behavior. To further explore this possibility, we used quantitative real-time PCR to examine relationships between mRNA expression of D1 as well as D2 receptors in the POM (and also the lateral septum and Area X) and sexually-motivated singing behavior in male European starlings. Results showed that both males with the highest and lowest D1 expression in the POM sang significantly less than males with intermediate levels of expression. Furthermore, singing behavior rose linearly in association with increasing levels of D1 expression in POM but dropped abruptly, such that individuals with D1 expression values higher than the mean sang very little. Analysis of birds with low and intermediate levels of D1 expression in POM revealed strong positive correlations between D1 expression and song but negative relationships between D2 receptor expression and song. These findings support prior work suggesting an optimal level of POM D1 receptor stimulation best facilitates sexually-motivated singing behavior. Results also suggest that D2 receptors may work in opposition to D1 receptors in POM to modify vocal production. PMID:26079111

  18. Noradrenergic signaling in the medial prefrontal cortex and amygdala differentially regulates vicarious trial-and-error in a spatial decision-making task.

    PubMed

    Amemiya, Seiichiro; Kubota, Natsuko; Umeyama, Nao; Nishijima, Takeshi; Kita, Ichiro

    2016-01-15

    In uncertain choice situations, we deliberately search and evaluate possible options before taking an action. Once we form a preference regarding the current situation, we take an action more automatically and with less deliberation. In rats, the deliberation process can be seen in vicarious trial-and-error behavior (VTE), which is a head-orienting behavior toward options at a choice point. Recent neurophysiological findings suggest that VTE reflects the rat's thinking about future options as deliberation, expectation, and planning when rats feel conflict. VTE occurs depending on the demand: an increase occurs during initial learning, and a decrease occurs with progression in learning. However, the brain circuit underlying the regulation of VTE has not been thoroughly examined. In situations in which VTE often appears, the medial prefrontal cortex (mPFC) and the amygdala (AMY) are crucial for learning and decision making. Our previous study reported that noradrenaline regulates VTE. Here, to investigate whether the mPFC and AMY are involved in regulation of VTE, we examined the effects of local injection of clonidine, an alpha2 adrenergic autoreceptor agonist, into either region in rats during VTE and choice behavior during a T-maze choice task. Injection of clonidine into either region impaired selection of the advantageous choice in the task. Furthermore, clonidine injection into the mPFC suppressed occurrence of VTE in the early phase of the task, whereas injection into the AMY inhibited the decrease in VTE in the later phase and thus maintained a high level of VTE throughout the task. These results suggest that the mPFC and AMY play a role in the increase and decrease in VTE, respectively, and that noradrenergic mechanisms mediate the dynamic regulation of VTE over experiences. PMID:26341318

  19. Targeted transplantation of iron oxide-labeled, adipose-derived mesenchymal stem cells in promoting meniscus regeneration following a rabbit massive meniscal defect

    PubMed Central

    QI, YIYING; YANG, ZHIGAO; DING, QIANHAI; ZHAO, TENGFEI; HUANG, ZHONGMING; FENG, GANG

    2016-01-01

    Repair of a massive meniscal defect remains a challenge in the clinic. However, targeted magnetic cell delivery, an emerging technique, may be useful in its treatment. The present study aimed to determine the effect of targeted intra-articular injection of superparamagnetic iron oxide (SPIO)-labeled adipose-derived mesenchymal stem cells (ASCs) in a rabbit model of a massive meniscal defect. ASCs may be directly labeled and almost 100% of the ASCs were labeled with SPIO after 24 h; these SPIO-labeled ASCs may be orientated by magnet. The centrifuged SPIO-labeled ASCs precipitations may be detected by magnetic resonance imaging (MRI). The anterior half of the medial meniscus of 18 New Zealand Rabbits was excised. After 7 days, the rabbits were randomized to injections of 2×106 SPIO-labeled ASCs, 2×106 unlabeled ASCs or saline. Permanent magnets were fixed to the outside of the operated joints for one day, and after 6 and 12 weeks, the knee joints were examined using MRI, gross and histological observation, and Prussian blue staining. Marked hypointense artifacts caused by SPIO-positive cells in the meniscus were detected using MRI. Histological observation revealed that the anterior portion of the meniscus was similar to the native tissue, demonstrating typical fibrochondrocytes surrounded by richer extracellular matrix in the SPIO-ASCs group. Collagen-rich matrix bridging the interface and the neo-meniscus integrated well with its host meniscus. Furthermore, degenerative changes occurred in all groups, but intra-articular injection of SPIO-ASCs or ASCs alleviated these degenerative changes. Prussian blue staining indicated that the implanted ASCs were directly associated with the regenerated tissue. Overall, targeted intra-articular delivery of SPIO-ASCs promoted meniscal regeneration whilst providing protective effects from osteoarthritic damage. PMID:26893631

  20. Trace Fear Conditioning Differentially Modulates Intrinsic Excitability of Medial Prefrontal Cortex–Basolateral Complex of Amygdala Projection Neurons in Infralimbic and Prelimbic Cortices

    PubMed Central

    Song, Chenghui; Ehlers, Vanessa L.

    2015-01-01

    Neuronal activity in medial prefrontal cortex (mPFC) is critical for the formation of trace fear memory, yet the cellular mechanisms underlying these memories remain unclear. One possibility involves the modulation of intrinsic excitability within mPFC neurons that project to the basolateral complex of amygdala (BLA). The current study used a combination of retrograde labeling and in vitro whole-cell patch-clamp recordings to examine the effect of trace fear conditioning on the intrinsic excitability of layer 5 mPFC–BLA projection neurons in adult rats. Trace fear conditioning significantly enhanced the intrinsic excitability of regular spiking infralimbic (IL) projection neurons, as evidenced by an increase in the number of action potentials after current injection. These changes were also associated with a reduction in spike threshold and an increase in h current. In contrast, trace fear conditioning reduced the excitability of regular spiking prelimbic (PL) projection neurons, through a learning-related decrease of input resistance. Interestingly, the amount of conditioned freezing was (1) positively correlated with excitability of IL-BLA projection neurons after conditioning and (2) negatively correlated with excitability of PL-BLA projection neurons after extinction. Trace fear conditioning also significantly enhanced the excitability of burst spiking PL-BLA projection neurons. In both regions, conditioning-induced plasticity was learning specific (observed in conditioned but not in pseudoconditioned rats), flexible (reversed by extinction), and transient (lasted <10 d). Together, these data suggest that intrinsic plasticity within mPFC–BLA projection neurons occurs in a subregion- and cell-type-specific manner during acquisition, consolidation, and extinction of trace fear conditioning. SIGNIFICANCE STATEMENT Frontal lobe-related function is vital for a variety of important behaviors, some of which decline during aging. This study involves a novel

  1. Differential Local Connectivity and Neuroinflammation Profiles in the Medial Prefrontal Cortex and Hippocampus in the Valproic Acid Rat Model of Autism.

    PubMed

    Codagnone, Martín Gabriel; Podestá, María Fernanda; Uccelli, Nonthué Alejandra; Reinés, Analía

    2015-01-01

    Autism spectrum disorders (ASD) are a group of developmental disabilities characterized by impaired social interaction, communication deficit and repetitive and stereotyped behaviors. Neuroinflammation and synaptic alterations in several brain areas have been suggested to contribute to the physiopathology of ASD. Although the limbic system plays an important role in the functions found impaired in ASD, reports on these areas are scarce and results controversial. In the present study we searched in the medial prefrontal cortex (mPFC) and hippocampus of rats exposed to the valproic acid (VPA) model of ASD for early structural and molecular changes, coincident in time with the behavioral alterations. After confirming delayed growth and maturation in VPA rats, we were able to detect decreased exploratory activity and social interaction at an early time point (postnatal day 35). In mPFC, although typical cortical column organization was preserved in VPA animals, we found that interneuronal space was wider than in controls. Hippocampal CA3 (cornu ammonis 3) pyramidal layer and the granular layer of the dentate gyrus both showed a disorganized spatial arrangement in VPA animals. Neuronal alterations were accompanied with increased tomato lectin and glial fibrillary acidic protein (GFAP) immunostainings both in the mPFC and hippocampus. In the latter region, the increased GFAP immunoreactivity was CA3 specific. At the synaptic level, while mPFC from VPA animals showed increased synaptophysin (SYN) immunostaining, a SYN deficit was found in all hippocampal subfields. Additionally, both the mPFC and the hippocampus of VPA rats showed increased neuronal cell adhesion molecule (NCAM) immunostaining together with decreased levels of its polysialylated form (PSA-NCAM). Interestingly, these changes were more robust in the CA3 hippocampal subfield. Our results indicate that exploratory and social deficits correlate with region-dependent neuronal disorganization and reactive

  2. In Vitro Repair of Meniscal Radial Tear Using Aligned Electrospun Nanofibrous Scaffold.

    PubMed

    Shimomura, Kazunori; Bean, Allison C; Lin, Hang; Nakamura, Norimasa; Tuan, Rocky S

    2015-07-01

    Radial tears of the meniscus represent one of the most common injuries of the knee, and result in loss of biomechanical meniscal function. However, there have been no established, effective treatments for radial meniscal tears. Nanofibrous materials produced by electrospinning have shown high promise in the engineering of soft musculoskeletal tissues. The goal of our study is to apply these technologies to develop a functional cell-seeded scaffold as a potential, new surgical method to enhance meniscal radial repair. Cylinder-shaped explants were excised from the inner avascular region of bovine meniscus and a radial tear was created in the center of the explant. The torn site was wrapped with either nanofibrous scaffold alone or scaffold seeded with meniscal fibrochondrocytes (MFC). A control group was prepared as explants without scaffolds or cells. The composite constructs in each group were cultured in vitro for 4 and 8 weeks, and these were then assessed histologically and mechanically. Histological analysis showed partial repair of the radial tear was observed with adherence between scaffold and native meniscal tissue in either the scaffold alone or cell-seeded scaffold group. Only the cell-seeded scaffold exhibited significant positive Picrosirius red staining and Safranin O staining. Mechanical testing of the repaired meniscus showed that the load-to-failure and stiffness values were significantly improved in the cell-seeded group. These results demonstrated the applicability of the MFC-seeded nanofibrous scaffold for meniscal radial tear repair based on both histological and mechanical analyses. In particular, the highly adhesive property of the cell-seeded scaffold to the meniscal tissue should be beneficial in helping to preserve the meniscal function by stabilizing meniscal fibers. PMID:25813386

  3. In Vitro Repair of Meniscal Radial Tear Using Aligned Electrospun Nanofibrous Scaffold

    PubMed Central

    Shimomura, Kazunori; Bean, Allison C.; Lin, Hang; Nakamura, Norimasa

    2015-01-01

    Radial tears of the meniscus represent one of the most common injuries of the knee, and result in loss of biomechanical meniscal function. However, there have been no established, effective treatments for radial meniscal tears. Nanofibrous materials produced by electrospinning have shown high promise in the engineering of soft musculoskeletal tissues. The goal of our study is to apply these technologies to develop a functional cell-seeded scaffold as a potential, new surgical method to enhance meniscal radial repair. Cylinder-shaped explants were excised from the inner avascular region of bovine meniscus and a radial tear was created in the center of the explant. The torn site was wrapped with either nanofibrous scaffold alone or scaffold seeded with meniscal fibrochondrocytes (MFC). A control group was prepared as explants without scaffolds or cells. The composite constructs in each group were cultured in vitro for 4 and 8 weeks, and these were then assessed histologically and mechanically. Histological analysis showed partial repair of the radial tear was observed with adherence between scaffold and native meniscal tissue in either the scaffold alone or cell-seeded scaffold group. Only the cell-seeded scaffold exhibited significant positive Picrosirius red staining and Safranin O staining. Mechanical testing of the repaired meniscus showed that the load-to-failure and stiffness values were significantly improved in the cell-seeded group. These results demonstrated the applicability of the MFC-seeded nanofibrous scaffold for meniscal radial tear repair based on both histological and mechanical analyses. In particular, the highly adhesive property of the cell-seeded scaffold to the meniscal tissue should be beneficial in helping to preserve the meniscal function by stabilizing meniscal fibers. PMID:25813386

  4. Meniscal Repair of Degenerative Horizontal Cleavage Tears Using Fibrin Clots

    PubMed Central

    Kamimura, Tamiko; Kimura, Masashi

    2014-01-01

    Background: Presently, the treatment options available for patients with horizontal degenerative cleavage tears of the meniscus are limited. These tears are considered an indication for partial or subtotal meniscectomy because when the tear is located within an avascular area, it is difficult to induce healing. However, meniscectomy is not ideal because it disrupts the normal anatomical structure and function of the meniscus. Purpose: To examine the clinical and arthroscopic outcomes following meniscal repair of degenerative horizontal cleavage tears using fibrin clots. Study Design: Case series; Level of evidence, 4. Methods: Vertical sutures were placed in the meniscal tear, and the cleft was filled with fibrin clots before the sutures were tightened. We repaired 18 menisci in 18 consecutive eligible patients using a previously described technique. Three patients with anterior cruciate ligament (ACL) injury who underwent simultaneous ACL reconstruction and 5 patients who did not undergo follow-up arthroscopy within 12 months were excluded. The remaining 10 menisci in 10 patients were evaluated in this study. The mean age of the patients was 35.8 ± 16.5 years, and the mean postoperative follow-up time was 40.8 ± 5.4 months. Pre- and postoperative Lysholm scores, International Knee Documentation Committee (IKDC) subjective scores, and Tegner activity levels were compared. The arthroscopy findings were evaluated at a mean postoperative time of 6.7 ± 2.9 months. Results: The mean Lysholm score improved significantly from 69.3 ± 16.3 points preoperatively to 95.4 ± 3.6 points postoperatively (P < .005). The mean IKDC subjective score also improved significantly from 26.5% ± 19.0% preoperatively to 87.8% ± 7.5% postoperatively (P < .001). The Tegner activity level recovered to the preinjury level in 6 patients and to 1 level below the preinjury level in 4 patients. The follow-up arthroscopies showed complete healing in 7 patients (70%) and incomplete healing in

  5. Unusual Presentation of Synovial Sarcoma as Meniscal Cyst: A Case Report

    PubMed Central

    Jamshidi, Khodamorad; Yahyazadeh, Hooman; Bagherifard, Abolfazl

    2015-01-01

    Periarticular cyst and cystic soft tissue lesion around the knee are common. Synovial sarcoma is a rare and malignant soft tissue tumor accounting for approximately 5% of soft tissue sarcoma. A case is presented where a lesion adjacent to the joint line of the knee was diagnosed clinically and on imaging as a meniscal cyst. MRI signal was homogenous and no concomitant meniscal tears were seen. The tissue diagnosis was monophasic synovial sarcoma. PMID:26550597

  6. In vitro synthesis of tensioned synoviocyte bioscaffolds for meniscal fibrocartilage tissue engineering

    PubMed Central

    2013-01-01

    Background Meniscal injury is a common cause of lameness in the dog. Tissue engineered bioscaffolds may be a treatment option for meniscal incompetency, and ideally would possess meniscus- like extracellular matrix (ECM) and withstand meniscal tensile hoop strains. Synovium may be a useful cell source for meniscal tissue engineering because of its natural role in meniscal deficiency and its in vitro chondrogenic potential. The objective of this study is to compare meniscal -like extracellular matrix content of hyperconfluent synoviocyte cell sheets (“HCS”) and hyperconfluent synoviocyte sheets which have been tensioned over wire hoops (tensioned synoviocyte bioscaffolds, “TSB”) and cultured for 1 month. Results Long term culture with tension resulted in higher GAG concentration, higher chondrogenic index, higher collagen concentration, and type II collagen immunoreactivity in TSB versus HCS. Both HCS and TSB were immunoreactive for type I collagen, however, HCS had mild, patchy intracellular immunoreactivity while TSB had diffuse moderate immunoreactivity over the entire bisocaffold. The tissue architecture was markedly different between TSB and HCS, with TSB containing collagen organized in bands and sheets. Both HCS and TSB expressed alpha smooth muscle actin and displayed active contractile behavior. Double stranded DNA content was not different between TSB and HCS, while cell viability decreased in TSB. Conclusions Long term culture of synoviocytes with tension improved meniscal- like extra cellular matrix components, specifically, the total collagen content, including type I and II collagen, and increased GAG content relative to HCS. Future research is warranted to investigate the potential of TSB for meniscal tissue engineering. PMID:24299420

  7. NANOINDENTATION OF THE INSERTIONAL ZONES OF HUMAN MENISCAL ATTACHMENTS INTO UNDERLYING BONE

    PubMed Central

    Hauch, K.N.; Oyen, M.L.; Odegard, G.M.; Haut Donahue, T. L.

    2009-01-01

    The fibrocartilagenous knee menisci are situated between the femoral condyles and tibia plateau and are primarily anchored to the tibia by means of four attachments at the anterior and posterior horns. Strong fixation of meniscal attachments to the tibial plateau provide resistance to extruding forces of the meniscal body, allowing the menisci to assist in load transmission from the femur to the tibia. Clinically, tears and ruptures of the meniscal attachments and insertion to bone are rare. While it has been suggested that the success of a meniscal replacement is dependent on several factors, one of which is the secure fixation and firm attachment of the replacement to the tibial plateau, little is known about the material properties of meniscal attachments and the transition in material properties from the meniscus to subchondral bone. The objective of this study was to use nanoindentation to investigate the transition from meniscal attachment into underlying subchondral bone through uncalcified and calcified fibrocartilage. Nanoindentation tests were performed on both the anterior and posterior meniscal insertions to measure the instantaneous elastic modulus and elastic modulus at infinite time. The elastic moduli were found to increase in a bi-linear fashion from the external ligamentous attachment to the subchondral bone. The elastic moduli for the anterior attachments were consistently larger than those for the matching posterior attachments at similar indentation locations. These results show that there is a gradient of stiffness from the superficial zones of the insertion close to the ligamentous attachment into the deeper zones of the bone. This information will be useful in the continued development of successful meniscal replacements and understanding of fixation of the replacements to the tibial plateau. PMID:19627840

  8. A new hydrogel for the conservative treatment of meniscal lesions: a randomized controlled study

    PubMed Central

    ZORZI, CLAUDIO; RIGOTTI, STEFANO; SCREPIS, DANIELE; GIORDAN, NICOLA; PIOVAN, GIANLUCA

    2015-01-01

    Purpose this study aimed to investigate the efficacy of intra-articular (IA) administration of a hydrogel formulation obtained from a hyaluronic acid (HA) derivative (HYADD4®) in the management of meniscal tears and in meniscal tear repair. Methods fifty subjects with degenerative meniscal tears were enrolled into this single-site, observer-blind, parallel-group study. Clinical evaluations were performed at baseline and after 14, 30 and 60 days. Clinical outcomes included: pain reduction (Visual Analog Scale), improvement of knee functionality (WOMAC questionnaire), reduction in length and depth of the meniscal lesion (MRI-confirmed) and SF-36 questionnaire scores. Local tolerability and safety were also investigated. Results a significant reduction in VAS pain (p< 0.001) in favor of HYADD4® was recorded at day 14 and maintained at all the follow-up assessments. Data on knee functionality were in line with the VAS pain assessment results. A significant reduction in length and depth of the meniscal lesion, assessed using MRI, was found in the HYADD4® group compared to the control group (p<0.001). Conclusions the results of this study may indicate a new treatment option in the conservative management of patients complaining of pain due to meniscal tears. The MRI data suggest that the hydrogel formulation of HA used in this study may also play a role in the healing process of the lesion. Level of evidence Level I, prospective randomized clinical trial. PMID:26889470

  9. 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

  10. Assessment of regeneration in meniscal lesions by use of mesenchymal stem cells derived from equine bone marrow and adipose tissue.

    PubMed

    González-Fernández, Maria L; Pérez-Castrillo, Saúl; Sánchez-Lázaro, Jaime A; Prieto-Fernández, Julio G; López-González, Maria E; Lobato-Pérez, Sandra; Colaço, Bruno J; Olivera, Elías R; Villar-Suárez, Vega

    2016-07-01

    OBJECTIVE To assess the ability to regenerate an equine meniscus by use of a collagen repair patch (scaffold) seeded with mesenchymal stem cells (MSCs) derived from bone marrow (BM) or adipose tissue (AT). SAMPLE 6 female Hispano-Breton horses between 4 and 7 years of age; MSCs from BM and AT were obtained for the in vitro experiment, and the horses were subsequently used for the in vivo experiment. PROCEDURES Similarities and differences between MSCs derived from BM or AT were investigated in vitro by use of cell culture. In vivo assessment involved use of a meniscus defect and implantation on a scaffold. Horses were allocated into 2 groups. In one group, defects in the medial meniscus were treated with MSCs derived from BM, whereas in the other group, defects were treated with MSCs derived from AT. Defects were created in the contralateral stifle joint but were not treated (control samples). RESULTS Both types of MSCs had universal stem cell characteristics. For in vivo testing, at 12 months after treatment, treated defects were regenerated with fibrocartilaginous tissue, whereas untreated defects were partially repaired or not repaired. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that MSCs derived from AT could be a good alternative to MSCs derived from BM for use in regenerative treatments. Results also were promising for a stem cell-based implant for use in regeneration in meniscal lesions. IMPACT FOR HUMAN MEDICINE Because of similarities in joint disease between horses and humans, these results could have applications in humans. PMID:27347833

  11. Percutaneous injections of Platelet rich plasma for treatment of intrasubstance meniscal lesions

    PubMed Central

    Blanke, Fabian; Vavken, Patrick; Haenle, Maximilian; von Wehren, Lutz; Pagenstert, Geert; Majewski, Martin

    2015-01-01

    Summary Introduction management of intrasubstance meniscal lesions is still controversial. Intrasubstance meniscal lesions can lead to reduced sports activity and meniscal rupture. Physical therapy is often not satisfactory. Therefore new treatment methods are requested. Platelet Rich Plasma (PRP) has the ability to regenerate tissue; this was proved in several experimental studies. Whether percutaneous injections of PRP are effective in intrasubstance meniscal lesions is unknown. We hypothesize that percutaneous PRP injections lead to pain relief and halt of progression on MRI over 6 months in patients with grade 2 meniscal lesions. Materials and methods ten recreational athletes with intrasubstance meniscal lesions (grade II according to Reicher) proven by MR-Imaging (MRI) were treated by percutaneous injections of PRP in the affected meniscal area. Three sequential injections in seven day intervals were performed in every patient. All injections were performed with image converter. Follow-up MRI was done six months after last injection in every patient. Level of sports activity and amount of pain at athletic loads according to numeric rating scale (NRS-11) were noted in each patient before injections and at the time of follow up MRI after six months. The t-test was used to determine statistical differences. Results four of ten patients (40%) showed decrease of meniscal lesion in follow up MRI after six months. Nine of ten patients (90%) complained about short episodes of heavy pain after the injections with average NRS-Score of 7.9 at daily loads after the last injection. Six of ten patients (60%) showed Improvement of NRS-Score at final follow up. Average NRS-Score improved significantly (p=0.027) from 6.9 before injections to 4.5 six month after treatment. Six of ten patients (60%) reported increase of sports activity compared to the situation before injections. In four patients (40%) additional surgical treatment was necessary because of persistent knee pain

  12. Meniscal Scaffolds - Preclinical Evidence to Support their Use: A Systematic Review.

    PubMed

    Di Matteo, Berardo; Perdisa, Francesco; Gostynska, Natalia; Kon, Elizaveta; Filardo, Giuseppe; Marcacci, Maurilio

    2015-01-01

    Arthroscopic meniscal treatment is the most common procedure performed in the orthopedic practice. Current management of meniscal pathology relies on different therapeutic options, ranging from selective meniscectomy, suturing, and to meniscal replacement by using either allografts or scaffolds. The progresses made in the field of regenerative medicine and biomaterials allowed to develop several meniscal substitutes, some of those currently used in the clinical practice. Before reaching the clinical application, these devices necessarily undergo accurate testing in the animal model: the aim of the present manuscript is to systematically review the scientific evidence derived by animal model results for the use of meniscal scaffolds, in order to understand the current state of research in this particular field and to identify the trends at preclinical level that may influence in the near future the clinical practice. Thirty-four papers were included in the present analysis. In 12 cases the meniscal scaffolds were used with cells to further stimulate tissue regeneration. With the exception of some negative reports regarding dacron-based scaffolds, the majority of the trials highlighted that biomaterials and bio-engineered scaffolds are safe and could play a beneficial role in stimulating meniscal healing and in chondral protection. With regard to the benefits of cell augmentation, the evidence is limited to a small number of studies and no conclusive evidence is available. However, preclinical evidence seems to suggest that cells could enhance tissue regeneration with respect to the use of biomaterials alone, and further research should confirm the translational potential of cell-based approach. PMID:26157531

  13. Meniscal Scaffolds - Preclinical Evidence to Support their Use: A Systematic Review

    PubMed Central

    Di Matteo, Berardo; Perdisa, Francesco; Gostynska, Natalia; Kon, Elizaveta; Filardo, Giuseppe; Marcacci, Maurilio

    2015-01-01

    Arthroscopic meniscal treatment is the most common procedure performed in the orthopedic practice. Current management of meniscal pathology relies on different therapeutic options, ranging from selective meniscectomy, suturing, and to meniscal replacement by using either allografts or scaffolds. The progresses made in the field of regenerative medicine and biomaterials allowed to develop several meniscal substitutes, some of those currently used in the clinical practice. Before reaching the clinical application, these devices necessarily undergo accurate testing in the animal model: the aim of the present manuscript is to systematically review the scientific evidence derived by animal model results for the use of meniscal scaffolds, in order to understand the current state of research in this particular field and to identify the trends at preclinical level that may influence in the near future the clinical practice. Thirty-four papers were included in the present analysis. In 12 cases the meniscal scaffolds were used with cells to further stimulate tissue regeneration. With the exception of some negative reports regarding dacron-based scaffolds, the majority of the trials highlighted that biomaterials and bio-engineered scaffolds are safe and could play a beneficial role in stimulating meniscal healing and in chondral protection. With regard to the benefits of cell augmentation, the evidence is limited to a small number of studies and no conclusive evidence is available. However, preclinical evidence seems to suggest that cells could enhance tissue regeneration with respect to the use of biomaterials alone, and further research should confirm the translational potential of cell-based approach. PMID:26157531

  14. Association Between Previous Meniscal Surgery and the Incidence of Chondral Lesions at Revision Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Brophy, Robert H.; Wright, Rick W.; David, Tal S.; McCormack, Robert G.; Sekiya, Jon K.; Svoboda, Steven J.; Huston, Laura J.; Haas, Amanda K.; Steger-May, Karen

    2013-01-01

    Background Knees undergoing revision anterior cruciate ligament (ACL) reconstruction typically have more intra-articular injuries than do knees undergoing primary reconstruction. Hypothesis Previous partial meniscectomy (PM) is associated with a higher rate of chondral lesions at revision ACL reconstruction, whereas previous meniscal repair (MR) is not associated with a higher rate of chondral lesions at revision ACL reconstruction, compared with knees undergoing revision ACL with no previous meniscal surgery. Study design Cohort study (Prevalence); Level of evidence, 2. Methods Data from a multicenter cohort was reviewed to determine the history of prior meniscal surgery (PM/MR) and the presence of grade II/III/IV chondral lesions at revision ACL reconstruction. The association between previous meniscal surgery and the incidence of chondral lesions was examined. Patient age was included as a covariate to determine if surgery type contributes predictive information independent of patient age. Results The cohort included 725 ACL revision surgeries. Chondrosis was associated with patient age (P < .0001) and previous meniscal surgery (P < .0001). After adjusting for patient age, knees with previous PM were more likely to have chondrosis than knees with previous MR (P = .003) or no previous meniscal surgery (P < .0001). There was no difference between knees without previous meniscal surgery and knees with previous MR (P = .7). Previous partial meniscectomy was associated with a higher rate of chondrosis in the same compartment compared with knees without previous meniscal surgery (P < .0001) and knees with previous MR (P ≤ .03). Conclusion The status of articular cartilage at the time of revision ACL reconstruction relates to previous meniscal surgery independent of the effect of patient age. Previous partial meniscectomy is associated with a higher incidence of articular cartilage lesions, whereas previous meniscal repair is not. Although this association may

  15. Role of computer aided detection (CAD) integration: case study with meniscal and articular cartilage CAD applications

    NASA Astrophysics Data System (ADS)

    Safdar, Nabile; Ramakrishna, Bharath; Saiprasad, Ganesh; Siddiqui, Khan; Siegel, Eliot

    2008-03-01

    Knee-related injuries involving the meniscal or articular cartilage are common and require accurate diagnosis and surgical intervention when appropriate. With proper techniques and experience, confidence in detection of meniscal tears and articular cartilage abnormalities can be quite high. However, for radiologists without musculoskeletal training, diagnosis of such abnormalities can be challenging. In this paper, the potential of improving diagnosis through integration of computer-aided detection (CAD) algorithms for automatic detection of meniscal tears and articular cartilage injuries of the knees is studied. An integrated approach in which the results of algorithms evaluating either meniscal tears or articular cartilage injuries provide feedback to each other is believed to improve the diagnostic accuracy of the individual CAD algorithms due to the known association between abnormalities in these distinct anatomic structures. The correlation between meniscal tears and articular cartilage injuries is exploited to improve the final diagnostic results of the individual algorithms. Preliminary results from the integrated application are encouraging and more comprehensive tests are being planned.

  16. Review of Meniscal Allograft Transplantation Focusing on Long-term Results and Evaluation Methods.

    PubMed

    Lee, Bum-Sik; Kim, Jong-Min; Sohn, Dong-Wook; Bin, Seong-Il

    2013-03-01

    With recognition of the biomechanical role of the meniscus, such as load distribution and joint stability in the knee joint, there has been a shift in the treatment of meniscal tears from open total meniscectomy to preservation of the meniscal functions as much as possible with symptomatic relief. Recently, technical development of meniscal surgery, with advanced arthroscopic equipment and instruments, enables biological reconstruction of load bearing functions in the meniscus deficient knee through allograft tissue transplantation as well as repair of torn menisci. Meniscal allograft transplantation (MAT) has been considered as one of the few viable treatment options for the young meniscectomized knees based on various animal experiments and clinical studies. Still, there is insufficient evidence for the long-term chondroprotective effect of human MAT. Some long-term follow-up studies showed that the technique resulted in graft degeneration, deformation, and tear, and structural changes in the remodeling process in early MAT cases, disrupting functional restoration of the original meniscus. Nevertheless, advanced outcomes are documented in some recent studies. The purpose of this article is to review the mid- and long-term follow-up results of MAT and to improve understanding of MAT with evaluation methods of meniscal transplants using magnetic resonance imaging or second-look arthroscopy. PMID:23508067

  17. Lateral meniscal variant with absence of the posterior coronary ligament.

    PubMed

    Neuschwander, D C; Drez, D; Finney, T P

    1992-09-01

    We reviewed the cases of 3468 patients who had had arthroscopy of the knee between January 1976 and December 1988. Twenty-six patients (0.8 per cent) had a partial or a complete discoid lateral meniscus, and seven (0.2 per cent) had the Wrisberg-variant-type lateral meniscus. Of the seven patients, six had operative stabilization of the meniscus and one had a partial lateral meniscectomy because of an irreparable complex tear. Subjective, objective, and radiographic evaluations were performed on the patients who had had stabilization of the meniscus. According to the scale of Tegner and Lysholm, the result was excellent in four patients, good in one, and fair in one. None of the six patients had a tear of the sutured meniscus after an average follow-up of thirty-two months (range, twenty-four to forty months). Two patients had progressive symptoms attributable to osteoarthrosis, but the changes in the articular cartilage had been present at the time of the index procedure. None of the seven Wrisberg-variant-type menisci demonstrated a true discoid shape of the meniscus. We therefore classified this lesion as a lateral meniscal variant with absence of the posterior coronary ligament. PMID:1400547

  18. Repairing Posteromedial Meniscocapsular Separation: A Technique Using Inside-Out Meniscal Repair Needles

    PubMed Central

    Joshi, Anant; Usman, Sajeer; Sabnis, Bhushan; Kini, Abhishek

    2016-01-01

    Posteromedial meniscocapsular separation of the knee has received renewed interest, with many articles describing a high incidence in association with anterior cruciate ligament injury. Various techniques have been described to address these lesions using all-inside meniscal repair sutures or using rotator cuff repair instruments through the posteromedial portal. Most orthopaedic surgeons are accustomed to using the “inside-out” meniscal repair technique with a double-armed suture. This technique is cost-effective and, in our opinion, more efficient in repairing such tears. We present our technique of repairing peripheral meniscocapsular lesions using an inside-out meniscal repair system. We believe that this technique is easily reproducible, is less time-consuming, and ensures a good “bite” of the capsular tissue, producing a robust repair. PMID:27073773

  19. Large lateral meniscal ganglion cyst extending into the intercondylar fossa of the knee.

    PubMed

    Jäger, Alwin; Eberhardt, Christian; Hailer, Nils P

    2004-07-01

    We report the case of a 31-year-old, otherwise healthy man with a large intra-articular meniscal ganglion cyst (27.7 x 13.5 mm) originating from the dorsal horn of the lateral meniscus. Clinically, the patient presented with knee pain in a squatting position. Magnetic resonance imaging revealed a large intra-articular cyst in the posterior compartment. At arthroscopic surgery, the ganglion cyst was found in the intercondylar space posteriorly to the posterior cruciate ligament. After removal of the ganglion cyst, a horizontal tear in the dorsal horn of the lateral meniscus was revealed and treated by partial meniscectomy. To our knowledge, a meniscal ganglion cyst originating from the lateral meniscus and extending into the joint is an extremely rare event, with only two previous reported cases. We review the current literature on the pathogenesis, distribution, and treatment of meniscal ganglion cysts. PMID:15243414

  20. Probabilistic Approach for Determining the Material Properties of Meniscal Attachments In Vivo Using Magnetic Resonance Imaging and a Finite Element Model.

    PubMed

    Kang, Kyoung-Tak; Kim, Sung-Hwan; Son, Juhyun; Lee, Young Han; Chun, Heoung-Jae

    2015-12-01

    The material properties of in vivo meniscal attachments were evaluated using a probabilistic finite element (FE) model and magnetic resonance imaging (MRI). MRI scans of five subjects were collected at full extension and 30°, 60°, and 90° flexion. One subject with radiographic evidence of no knee injury and four subjects with Kellgren-Lawrence score of 1 or 2 (two each) were recruited. Isovoxel sagittal three-dimensional cube sequences of the knee were acquired in extension and flexion. Menisci movement in flexion was investigated using sensitivity analysis based on the Monte Carlo method in order to generate a subject-specific FE model to evaluate significant factors. The material properties of horn attachment in the five-subject FE model were optimized to minimize the differences between meniscal movements in the FE model and MR images in flexion. We found no significant difference between normal and patient knees in flexion with regard to movement of anterior, posterior, medial, and lateral menisci or changes in height morphology. At 90° flexion, menisci movement was primarily influenced by posterior horn stiffness, followed by anterior horn stiffness, the transverse ligament, and posterior cruciate ligament. The optimized material properties model predictions for menisci motion were more accurate than the initial material properties model. The results of this approach suggest that the material properties of horn attachment, which affects the mobile characteristics of menisci, could be determined in vivo. Thus, this study establishes a basis for a future design method of attachment for tissue-engineered replacement menisci. PMID:26402397

  1. Multiple injections of leukoreduced platelet rich plasma reduce pain and functional impairment in a canine model of ACL and meniscal deficiency.

    PubMed

    Cook, James L; Smith, Patrick A; Bozynski, Chantelle C; Kuroki, Keiichi; Cook, Cristi R; Stoker, Aaron M; Pfeiffer, Ferris M

    2016-04-01

    Platelet rich plasma (PRP) is used to treat many musculoskeletal disorders. We used a canine model to determine the effects of multiple intra-articular injections of leukoreduced PRP (ACP) on anterior cruciate ligament healing, meniscal healing, and progression of osteoarthritis (OA). With Animal Care and Use Committee (ACUC) approval, 12 dogs underwent partial ACL transection and meniscal release in one knee. At weeks 1, 2, 3, 6, and 8 after insult, dogs were treated with intra-articular injections (2 ml) of either ACP (n = 6) or saline (n = 6). Dogs were assessed over 6 months to determine comfortable range of motion (CROM), lameness, pain, effusion, kinetics, and radiographic and arthroscopic assessments. At 6-month endpoint, dogs were assessed for ACL material properties and histopathology. Saline-treated dogs had significantly (p < 0.04) more CROM loss, significantly (p < 0.01) more pain, significantly (p < 0.05) more severe lameness, significantly (p < 0.05) lower function, and significantly (p < 0.05) lower %Total Pressure Index in affected hindlimbs compared to ACP-treated dogs. Radiographic OA increased significantly (p < 0.01) over time within each group. Arthroscopically, saline-treated knees showed moderate to severe synovitis, further ACL disruption, and medial compartment cartilage loss, and ACP-treated knees showed evidence of ACL repair and less severe synovitis. ACL material properties in ACP-treated knees were closer to normal than in saline-treated knees, however, the differences were not statistically significant. ACL histopathology was significantly (p< 0.05) less severe in ACP-treated knees compared to saline-treated knees. Five intra-articular injections of leukoreduced PRP had beneficial effects for ACL healing, improved range of motion, decreased pain, and improved limb function for up to 6 months in this model. PMID:26403590

  2. 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

  3. [THE EVOLUTION IN TREATING MENISCAL TEARS--FROM RESECTION TO SUTURING].

    PubMed

    Stahl, Ido; Shapira, Jackob; Peskin, Bezalel; Hous, Nir; Norman, Doron; Falah, Mazen

    2016-05-01

    The meniscus has an important biomechanical role in the normal function of the knee including load bearing, shock absorption and joint stability. Tears of the meniscus are one of the common sports injuries. The knowledge that total meniscectomy causes early development of degenerative changes has raised the prevalence of meniscal tear repair in order to preserve as much as possible of the meniscal tissue. The type of tear (degenerative of traumatic), shape and location have a critical effect on healing ability after suture of the tear and thus will determine the treatment plan. PMID:27526563

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

    PubMed

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

    2006-11-01

    Although several quantitative magnetic resonance (MR) diagnostic criteria for discoid lateral meniscus (DLM) have been described, there are no criteria by which to estimate the size of the medial meniscus. We define a medial meniscus that exceeds the normal size as a "large medial meniscus" (LMM), and the purpose of this study is to establish the quantitative MR diagnostic criteria for LMM. The MR imaging findings of 96 knees with arthroscopically confirmed intact semilunar lateral meniscus (SLM), 18 knees with intact DLM, 105 knees with intact semilunar medial meniscus (SMM) and 4 knees with torn LMM were analyzed. The following three quantitative parameters were measured: (a) meniscal width (MW): the minimum MW on the coronal slice; (b) ratio of the meniscus to the tibia (RMT): the ratio of minimum MW to maximum tibial width on the coronal slice; (c) continuity of the anterior and posterior horns (CAPH): the number of consecutive 5-mm-thick sagittal slices showing continuity between the anterior horn and the posterior horn of the meniscus on sagittal slices. Using logistic discriminant analysis between intact SLM and DLM groups and using descriptive statistics of intact SLM and SMM groups, the cutoff values used to discriminate LMM from SMM were calculated by MW and RMT. Moreover, the efficacy of these cutoff values and three slices of the cutoff values for CAPH were estimated in the medial meniscus group. "MW> or =11 mm" and "RMT> or =15%" were determined to be effective diagnostic criteria for LMM, while three of four cases in the torn LMM group were true positives and specificity was 99% in both criteria. When "CAPH> or =3 slices" was used as a criterion, three of four torn LMM cases were true positives and specificity was 93%. PMID:17071338

  5. The Role of Cells in Meniscal Guided Tissue Regeneration

    PubMed Central

    Jülke, Henriette; Mainil-Varlet, Pierre; Jakob, Roland P.; Brehm, Walter; Schäfer, Birgit

    2015-01-01

    Objective: Successful repair of defects in the avascular zone of meniscus remains a challenge in orthopedics. This proof of concept study aimed to investigate a guided tissue regeneration approach for treatment of tears in meniscus avascular zone in a goat model. Design: Full-depth longitudinal tear was created in the avascular zone of the meniscus and sutured. In the two treatment groups, porcine collagen membrane was wrapped around the tear without (CM) or with injection of expanded autologous chondrocytes (CM+cells), whereas in the control group the tear remained only sutured. Gait recovery was evaluated during the entire follow-up period. On explantation at 3 and 6 months, macroscopic gross inspection assessed healing of tears, degradation of collagen membrane, potential signs of inflammation, and osteoarthritic changes. Microscopic histology scoring criteria were developed to evaluate healing of tears, the cellular response, and the inflammatory response. Results: Gait recovery suggested protective effect of collagen membrane and was supported by macroscopical evaluation where improved tear healing was noted in both treated groups. Histology scoring in CM compared to suture group revealed an increase in tear margins contact, newly formed connective tissue between margins, and cell formations surrounded with new matrix after 3 months yet not maintained after 6 months. In contrast, in the CM+cells group these features were observed after 3 and 6 months. Conclusions: A transient, short-term guided tissue regeneration of avascular meniscal tears occurred upon application of collagen membrane, whereas addition of expanded autologous chondrocytes supported more sustainable longer term tear healing. PMID:26069707

  6. 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 ...

  7. 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

  8. Experimental study on thermal welding for the knee meniscal white zone.

    PubMed

    Imakiire, Naoaki; Kotani, Akihiro; Ishii, Yoshiaki

    2003-01-01

    It is difficult to repair tears of the meniscus at the white zone by suturing. We considered that there might be an optimal tissue welding temperature when thermally welding the meniscal white zone, so we conducted a thermal welding experiment using bovine and human menisci. The samples prepared after thermal welding were investigated by measuring the tensile strength, analyzing the histological findings of the welded portion and the meniscal parenchyma, and conducting biochemical analyses. In the experiment using human menisci, histological findings were investigated using transmission electron microscopy (TEM). As the findings on the welded tissue in the white zone of the bovine meniscus indicated positive results at 63 degrees C and 69 degrees C, the experiments using human meniscal white zone were conducted at these two temperatures. The highest tensile strength after thermal welding of the human meniscal white zone was 101.4 +/- 2.6 g/cm(2) at 63 degrees C. Although there were no significant differences in the amount of pyridinoline per unit collagen weight [Pyr/Hpr (%)] in the human meniscus after thermal welding between the control group and various temperature groups (55 degrees C, 63 degrees C, 69 degrees C, 75 degrees C), the amount of pyridinoline per unit of collagen weight tended to decline as the welding temperature increased. According to the TEM findings, the internal structure of the nuclei of the cells was preserved in the 63 degrees C group, whereas cells were denatured inside the nuclei in the 69 degrees C group. They exhibited necrosis, making cell regeneration difficult. Therefore, it seems feasible that thermal welding at 63 degrees C can repair tears in the human meniscal white zone. PMID:14557935

  9. ISAKOS classification of meniscal tears-illustration on 2D and 3D isotropic spin echo MR imaging.

    PubMed

    Wadhwa, Vibhor; Omar, Hythem; Coyner, Katherine; Khazzam, Michael; Robertson, William; Chhabra, Avneesh

    2016-01-01

    Magnetic Resonance Imaging is modality of choice for the non-invasive evaluation of meniscal tears. Accurate and uniform documentation of meniscal pathology is necessary for optimal multi-disciplinary communication, to guide treatment options and for validation of patient outcomes studies. The increasingly used ISAKOS arthroscopic meniscus tear classification system has been shown to provide sufficient interobserver reliability among the surgeons. However, the terminology is not in common use in the radiology world. In this article, the authors discuss the MR imaging appearances of meniscal tears based on ISAKOS classification on 2D and multiplanar 3D isotropic spin echo imaging techniques and illustrate the correlations of various meniscal pathologies with relevant arthroscopic images. PMID:26724644

  10. Large regional differences in incidence of arthroscopic meniscal procedures in the public and private sector in Denmark

    PubMed Central

    Hare, Kristoffer Borbjerg; Vinther, Jesper Høeg; Lohmander, L Stefan; Thorlund, Jonas Bloch

    2015-01-01

    Objectives A recent study reported a large increase in the number of meniscal procedures from 2000 to 2011 in Denmark. We examined the nation-wide distribution of meniscal procedures performed in the private and public sector in Denmark since different incentives may be present and the use of these procedures may differ from region to region. Setting We included data on all patients who underwent an arthroscopic meniscal procedure performed in the public or private sector in Denmark. Participants Data were retrieved from the Danish National Patient Register on patients who underwent arthroscopic meniscus surgery as a primary or secondary procedure in the years 2000 to 2011. Hospital identification codes enabled linkage of performed procedures to specific hospitals. Primary and secondary outcome measures Yearly incidence of meniscal procedures per 100 000 inhabitants was calculated with 95% CIs for public and private procedures for each region. Results Incidence of meniscal procedures increased at private and at public hospitals. The private sector accounted for the largest relative and absolute increase, rising from an incidence of 1 in 2000 to 98 in 2011. In 2011, the incidence of meniscal procedures was three times higher in the Capital Region than in Region Zealand. Conclusions Our study identified a large increase in the use of meniscal procedures in the public and private sector in Denmark. The increase was particularly conspicuous in the private sector as its proportion of procedures performed increased from 1% to 32%. Substantial regional differences were present in the incidence and trend over time of meniscal procedures. PMID:25712820

  11. Meniscal suture. An experimental study in the dog.

    PubMed

    Kawai, Y; Fukubayashi, T; Nishino, J

    1989-06-01

    A longitudinal tear was made and then sutured in the peripheral quarter of the medial meniscus of 43 dogs. The sutured menisci were examined using histologic and microangiographic techniques at regular intervals during a 12-week period. Biomechanical tests were also performed. The healing process was promoted not only by the synovial blood supply but also by the peripheral blood supply. Even at the end of 12 weeks, the healing tissue was mainly composed of fibrous tissue, but chondrocytelike cells were also found. The tensile forces were calculated and compared with the opposite leg. The maximum tensile strength reached 80% of that of the opposite side at the end of the 12-week period. PMID:2656029

  12. 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

  13. 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

  14. Relevance of history of injury to the diagnosis of meniscal tears.

    PubMed Central

    Burnett, R.; Allum, R. L.

    1993-01-01

    A consecutive series of 217 arthroscopic meniscectomies has been reviewed in order to investigate the incidence of significant meniscal lesions without obvious precipitating injury. There were 10 bucket handle tears out of 117 (9%) with a mean age of 32 years with no significant injury; 18 flap tears out of 69 (26%) with a mean age of 40 years; and 7 out of 19 (37%) radial tears with a mean age of 36 years also had no significant injury. This study indicates that the absence of a history of injury in the young patient with a symptomatic knee does not exclude significant meniscal tears, such as a bucket handle, and therefore has implications for history taking and diagnosis. PMID:8379621

  15. An unusual case of vascular abnormality mimicking a lateral meniscal cyst.

    PubMed

    Vergis, A; Maletius, W; Messner, K

    1995-10-01

    An unusual case of a vascular abnormality mimicking a lateral meniscal cyst is reported. The patient was a 31-year-old active sportsman who presented with intermittent pain over the lateral aspect of the left knee joint line, occurring only during activities involving twisting motions such as playing soccer. He did not experience local tenderness or swelling, clicking, locking, or giving way. The magnetic resonance imaging, which was done after a diagnostic arthroscopy with normal intra-articular findings, showed a cyst formation of approximately 4-mm diameter adjacent to the lateral meniscus periphery, but no meniscal tissue degeneration. Exactly at the preoperatively marked site of most intensive pain sensation during twisting motions, surgical exposure showed a venous-aneurysm-like tumor, which was removed. The operation resulted in complete relief of symptoms and undisturbed sporting activities including soccer. PMID:8534307

  16. The role of meniscal tissue in joint protection in early osteoarthritis.

    PubMed

    Verdonk, Rene; Madry, Henning; Shabshin, Nogah; Dirisamer, Florian; Peretti, Giuseppe M; Pujol, Nicolas; Spalding, Tim; Verdonk, Peter; Seil, Romain; Condello, Vincenzo; Di Matteo, Berardo; Zellner, Johannes; Angele, Peter

    2016-06-01

    It is widely accepted that partial meniscectomy leads to early onset of osteoarthritis (OA). A strong correlation exists between the amount and location of the resected meniscus and the development of degenerative changes in the knee. On the other hand, osteoarthritic changes of the joint alter the structural and functional integrity of meniscal tissue. These alterations might additionally compromise the limited healing capacity of the meniscus. In young, active patients without cartilage damage, meniscus therapy including partial meniscectomy, meniscus suture, and meniscus replacement has proven beneficial effects in long-term studies. Even in an early osteoarthritic milieu, there is a relevant regenerative potential of the meniscus and the surrounding cartilage. This potential should be taken into account, and meniscal surgery can be performed with the correct timing and the proper indication even in the presence of early OA. PMID:27085362

  17. Synovial chemokine expression and relationship with knee symptoms in patients with meniscal tears

    PubMed Central

    Nair, Anjali; Gan, Justin; Bush-Joseph, Charles; Verma, Nikhil; Tetreault, Matthew W.; Saha, Kanta; Margulis, Arkady; Fogg, Louis; Scanzello, Carla R.

    2015-01-01

    Objective In patients with knee OA, synovitis is associated with knee pain and symptoms. We previously identified synovial mRNA expression of a set of chemokines (CCL19, IL-8, CCL5, XCL-1, CCR7) associated with synovitis in patients with meniscal tears but without radiographic OA. CCL19 and CCR7 were also associated with knee symptoms. This study sought to validate expression of these chemokines and association with knee symptoms in more typical patients presenting for meniscal arthroscopy, many who have pre-existing OA. Design Synovial biopsies and fluid (SF) were collected from patients undergoing meniscal arthroscopy. Synovial mRNA expression was measured using quantitative RT-PCR. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was administered preoperatively. Regression analyses determined if associations between chemokine mRNA levels and KOOS scores were independent of other factors including radiographic OA. CCL19 in SF was measured by ELISA, and compared to patients with advanced knee OA and asymptomatic organ donors. Results 90% of patients had intra-operative evidence of early cartilage degeneration. CCL19, IL-8, CCL5, XCL1, CCR7 transcripts were detected in all patients. Synovial CCL19 mRNA levels independently correlated with KOOS Activities of Daily Living scores (95% CI [-8.071, -0.331], p= 0.036), indicating higher expression was associated with more knee-related dysfunction. SF CCL19 was detected in 7 of 10 patients, compared to 4 of 10 asymptomatic donors. Conclusion In typical patients presenting for meniscal arthroscopy, synovial CCL19 mRNA expression was associated with knee-related difficulty with activities of daily living, independent of other factors including presence of radiographic knee OA. PMID:25724256

  18. Financial impact of radiological reports on medical-legal evaluation of compensation for meniscal lesions.

    PubMed

    Lelario, M; Ciuffreda, P; Lupo, P; Bristogiannis, C; Vinci, R; Stoppino, L P; De Filippo, M; Macarini, L

    2013-08-01

    To evaluate any discrepancy between radiological reports for clinical purposes and for medicolegal purposes and to quantify its economic impact on repayments made by private insurance companies for meniscal injuries of the knee. The medical records obtained pertaining to 108 knee injury patients (mean age 43.3 years) assessed over a period of 12 months were analysed. Clinical medical reports, aimed at assessing the lesion, and medicolegal reports, drawn up with a view to quantifying compensation, were compared. Unlike reports for clinical purposes in reports for medicolegal purposes, in the evaluation of meniscal lesions, in addition to morphological features of lesions, chronological, topographical, severity and exclusion criteria were applied. To estimate the economic impact resulting from the biological damage, we consulted an actuarial table based on the 9-point minor incapacity classification system. Meniscal lesions not compatible with a traumatic event and therefore not eligible for an insurance payout were found in 56 patients. Of these, 37 failed exclusion criteria, while 19 failed to meet chronological criteria. This difference resulted in a reduction in compensation made by private insurance companies with savings estimated with a saving between euro 203,715.41 and euro 622,315.39. The use of a clinical report for medicolegal purposes can be a source of valuation error, as chronological and/or dynamic information regarding the trauma mechanism may be lacking. Therefore, the use of a full radiological appraisal allows a better damage's assessment and an adequate compensation for injuries. PMID:23949935

  19. Radiofrequency stimulation for potential healing of meniscal injuries in the avascular zone.

    PubMed

    Lee, Christopher S; Tasto, James P; Healey, Robert M; Sano, Sakae; Amiel, David

    2014-12-01

    We conducted this study to evaluate the effect of radiofrequency (RF) stimulation with suture repair on the healing of tears in the meniscal white-white zone. Fifty-four New Zealand white rabbits underwent surgically induced meniscal injuries within the white-white region. RF was applied using a 0.8-mm TOPAZ MicroDebrider RF wand (ArthroCare) at level 4 for 500 milliseconds. Rabbits were sacrificed at 28 and 84 days for gross and histologic analysis by 3 blinded observers and at 9, 28, and 84 days for biochemical examination. Biochemical analyses included evaluation of cell proliferation (3H-thymidine), as well as mitogenic (IGF-1, bFGF) and angiogenic (VEGF, αV) factors. Of specimens repaired with RF combined with suture, 19 (58%) showed a degree of gross morphologic and histologic healing. No significant healing was seen in specimens with either no repair or repair with suture alone. We observed a 40% increase in cellular proliferation when RF supplementation was used (P<.05). With regards to mitogenic and angiogenic markers (IGF-1, bFGF, VEGF, and αV), there was a significant increase in groups treated with RF at 9 and 28 days (P>0.05). RF supplementation of avascular zone meniscal repairs may lead to an increased healing response. PMID:25490015

  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. 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

  2. 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

  3. Automated discovery of meniscal tears on MR imaging: a novel high-performance computer-aided detection application for radiologists

    NASA Astrophysics Data System (ADS)

    Ramakrishna, Bharath; Safdar, Nabile; Siddiqui, Khan; Kim, Woojin; Liu, Weimin; Saiprasad, Ganesh; Chang, Chein-I.; Siegel, Eliot

    2008-03-01

    Knee-related injuries including meniscal tears are common in both young athletes and the aging population and require accurate diagnosis and surgical intervention when appropriate. With proper techniques and radiologists' experienced skills, confidence in detection of meniscal tears can be quite high. However, for radiologists without musculoskeletal training, diagnosis of meniscal tears can be challenging. This paper develops a novel computer-aided detection (CAD) diagnostic system for automatic detection of meniscal tears in the knee. Evaluation of this CAD system using an archived database of images from 40 individuals with suspected knee injuries indicates that the sensitivity and specificity of the proposed CAD system are 83.87% and 75.19%, respectively, compared to the mean sensitivity and specificity of 77.41% and 81.39%, respectively obtained by experienced radiologists in routine diagnosis without using the CAD. The experimental results suggest that the developed CAD system has great potential and promise in automatic detection of both simple and complex meniscal tears of knees.

  4. 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

  5. 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

  6. 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

  7. Growth factor treated tensioned synoviocyte neotissues: towards meniscal bioscaffold tissue engineering.

    PubMed

    Warnock, J J; Bobe, G; Duesterdieck-Zellmer, K F; Spina, J; Ott, J; Baltzer, W I; Bay, B K

    2014-04-01

    Meniscal injury is a common cause of osteoarthritis, pain, and disability in dogs and humans, but tissue-engineered bioscaffolds could be a treatment option for meniscal deficiency. The objective of this study was to compare meniscus-like matrix histology, composition, and biomechanical properties of autologous tensioned synoviocyte neotissues (TSN) treated with fetal bovine serum (TSNfbs) or three chondrogenic growth factors (TSNgf). Fourth passage canine synoviocytes from 10 dogs were grown in hyperconfluent monolayer culture, formed into TSN, and then cultured for 3 weeks with 17.7% FBS or three human recombinant TSNgf (bFGF, TGF-β1, and IGF-1). Cell viability was determined with laser microscopy. Histological architecture and the composition of fibrocartilage matrix were evaluated in TSN by staining tissues for glycosaminoglycan (GAG), α-smooth muscle actin, and collagen 1 and 2; quantifying the content of GAG, DNA, and hydroxyproline; and measuring the gene expression of collagens type 1α and 2α, the GAG aggrecan, and transcription factor Sry-type Homeobox Protein-9 (SOX9). Biomechanical properties were determined by materials testing force-deformation curves. The TSN contained components and histological features of mensical fibrocartilage extracellular matrix. Growth factor-treated TSN had higher DNA content but lower cell viability than TSNfbs. TSNgf had greater fibrocartilage-like matrix content (collagen 2 and GAG content with increased collagen 2α and SOX9 gene expression). Additionally, TSNgf collagen was more organized histologically and so had greater tensile biomechanical properties. The results indicate the potential of TSN when cultured with growth factors as implantable bioscaffolds for the treatment of canine meniscal deficiency. PMID:24559744

  8. A history of meniscal surgery: from ancient times to the twenty-first century.

    PubMed

    Di Matteo, B; Moran, C J; Tarabella, V; Viganò, A; Tomba, P; Marcacci, M; Verdonk, R

    2016-05-01

    The science and surgery of the meniscus have evolved significantly over time. Surgeons and scientists always enjoy looking forward to novel therapies. However, as part of the ongoing effort at optimizing interventions and outcomes, it may also be useful to reflect on important milestones from the past. The aim of the present manuscript was to explore the history of meniscal surgery across the ages, from ancient times to the twenty-first century. Herein, some of the investigations of the pioneers in orthopaedics are described, to underline how their work has influenced the management of the injured meniscus in modern times. Level of evidence V. PMID:26231150

  9. 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

  10. 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

  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. Using a statistically calibrated biphasic finite element model of the human knee joint to identify robust designs for a meniscal substitute.

    PubMed

    Leatherman, Erin R; Guo, Hongqiang; Gilbert, Susannah L; Hutchinson, Ian D; Maher, Suzanne A; Santner, Thomas J

    2014-07-01

    This paper describes a methodology for selecting a set of biomechanical engineering design variables to optimize the performance of an engineered meniscal substitute when implanted in a population of subjects whose characteristics can be specified stochastically. For the meniscal design problem where engineering variables include aspects of meniscal geometry and meniscal material properties, this method shows that meniscal designs having simultaneously large radial modulus and large circumferential modulus provide both low mean peak contact stress and small variability in peak contact stress when used in the specified subject population. The method also shows that the mean peak contact stress is relatively insensitive to meniscal permeability, so the permeability used in the manufacture of a meniscal substitute can be selected on the basis of manufacturing ease or cost. This is a multiple objective problem with the mean peak contact stress over the population of subjects and its variability both desired to be small. The problem is solved by using a predictor of the mean peak contact stress across the tibial plateau that was developed from experimentally measured peak contact stresses from two modalities. The first experimental modality provided computed peak contact stresses using a finite element computational simulator of the dynamic tibial contact stress during axial dynamic loading. A small number of meniscal designs with specified subject environmental inputs were selected to make computational runs and to provide training data for the predictor developed below. The second experimental modality consisted of measured peak contact stress from a set of cadaver knees. The cadaver measurements were used to bias-correct and calibrate the simulator output. Because the finite element simulator is expensive to evaluate, a rapidly computable (calibrated) Kriging predictor was used to explore extensively the contact stresses for a wide range of meniscal engineering

  13. 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

  14. 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

  15. Changes in rates of arthroscopy due to degenerative knee disease and traumatic meniscal tears in Finland and Sweden

    PubMed Central

    Mattila, Ville M; Sihvonen, Raine; Paloneva, Juha; Felländer-Tsai, Li

    2016-01-01

    Background and purpose Knee arthroscopy is commonly performed to treat degenerative knee disease symptoms and traumatic meniscal tears. We evaluated whether the recent high-quality randomized control trials not favoring arthroscopic surgery for degenerative knee disease affected the procedure incidence and trends in Finland and Sweden. Patients and methods We conducted a bi-national registry-based study including all adult (aged ≥18 years) inpatient and outpatient arthroscopic surgeries performed for degenerative knee disease (osteoarthritis (OA) and degenerative meniscal tears) and traumatic meniscal tears in Finland between 1997 and 2012, and in Sweden between 2001 and 2012. Results In Finland, the annual number of operations was 16,389 in 1997, reached 20,432 in 2007, and declined to 15,018 in 2012. In Sweden, the number of operations was 9,944 in 2001, reached 11,711 in 2008, and declined to 8,114 in 2012. The knee arthroscopy incidence for OA was 124 per 105 person-years in 2012 in Finland and it was 51 in Sweden. The incidence of knee arthroscopies for meniscal tears coded as traumatic steadily increased in Finland from 64 per 105 person-years in 1997 to 97 per 105 person-years in 2012, but not in Sweden. Interpretation The incidence of arthroscopies for degenerative knee disease declined after 2008 in both countries. Remarkably, the incidence of arthroscopy for degenerative knee disease and traumatic meniscal tears is 2 to 4 times higher in Finland than in Sweden. Efficient implementation of new high-quality evidence in clinical practice could reduce the number of ineffective surgeries. PMID:26122621

  16. Bovine meniscal tissue exhibits age- and interleukin-1 dose-dependent degradation patterns and composition-function relationships.

    PubMed

    Ling, Carrie H-Y; Lai, Janice H; Wong, Ivan J; Levenston, Marc E

    2016-05-01

    Despite increasing evidence that meniscal degeneration is an early event in the development of knee osteoarthritis, relatively little is known regarding the sequence or functional implications of cytokine-induced meniscal degradation or how degradation varies with age. This study examined dose-dependent patterns of interleukin-1 (IL-1)-induced matrix degradation in explants from the radially middle regions of juvenile and adult bovine menisci. Tissue explants were cultured for 10 days in the presence of 0, 1.25, 5, or 20 ng/ml recombinant human IL-1α. Juvenile explants exhibited immediate and extensive sulfated glycosaminoglycan (sGAG) loss and subsequent collagen release beginning after 4-6 days, with relatively little IL-1 dose-dependence. Adult explants exhibited a more graded response to IL-1, with dose-dependent sGAG release and a lower fraction of sGAG released (but greater absolute release) than juvenile explants. In contrast to juvenile explants, adult explants exhibited minimal collagen release over the 10-day culture. Compressive and shear moduli reflected the changes in explant composition, with substantial decreases for both ages but a greater relative decrease in juvenile tissue. Dynamic moduli exhibited stronger dependence on explant sGAG content for juvenile tissue, likely reflecting concomitant changes to both proteoglycan and collagen tissue components. The patterns of tissue degradation suggest that, like in articular cartilage, meniscal proteoglycans may partially protect collagen from cell-mediated degeneration. A more detailed view of functional changes in meniscal tissue mechanics with degeneration will help to establish the relevance of in vitro culture models and will advance understanding of how meniscal degeneration contributes to overall joint changes in early stage osteoarthritis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:801-811, 2016. PMID:26519862

  17. 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

  18. Chondroblastoma of the Medial Malleolus: A Case Report of A Rare Tumor at an Extremely Uncommon Site

    PubMed Central

    Tiwari, Mukesh; Chaturvedi, Hemant; Patel, Vaibhav; Matti, Rajarshi

    2016-01-01

    Introduction: Tumors of the medial malleolus are rare. Chondrogenic tumors of the medial malleolus are extremely rare. Chondroblastoma of the medial malleolus has not been reported previously in the English literature. The purpose is to present a rare tumor occurring at an unusual site and its successful management. Case Presentation: We report a case of a 30 years old female with chondroblastoma of the medial malleolus with its clinical features, radiographic features, differential diagnosis, and management at an unusual site. Treatment comprised of an open biopsy followed by aggressive curettage, phenolization and bone cement. Symptoms resolved after treatment with resumption of normal activities and no signs of recurrence at 1 year follow-up. Conclusion: This case appears to be the first reported case of chondroblastoma occurring at medial malleolus. The present case report will increase the awareness of this rare tumor occurring at this unusual site thereby avoiding any chance of misdiagnosis. PMID:27299121

  19. Morphometric Differences between the Medial and Lateral Meniscus in Healthy Men – A Three-Dimensional Analysis Using Magnetic Resonance Imaging

    PubMed Central

    Bloecker, K.; Wirth, W.; Hudelmaier, M.; Burgkart, R.; Frobell, R.; Eckstein, F.

    2012-01-01

    The objective of this work was to characterize tibial plateau coverage and morphometric differences of the medial (MM) and lateral meniscus (LM) in a male reference cohort using three-dimensional imaging. Coronal multiplanar reconstructions of a sagittal double-echo steady state with water excitation magnetic resonance sequence (slice thickness: 1.5 mm, and in-plane resolution: 0.37 × 0.70 mm) were analyzed in 47 male participants without symptoms, signs or risk factors of knee osteoarthritis of the reference cohort of the Osteoarthritis Initiative. The medial and lateral tibial (LT) plateau cartilage area and the tibial, femoral and external surfaces of the MM and LM were manually segmented throughout the entire knee. This process was assisted by parallel inspection of a coronal intermediately weighted turbo spin echo sequence. Measures of tibial coverage, meniscus size, and meniscus position were computed three-dimensionally for the total menisci, the body, and the anterior and the posterior horn. The LM was found to cover a significantly greater (p < 0.001) proportion of the LT plateau (59 ± 6.8%) than the MM of the medial plateau (50 ± 5.5%). Whereas the volume of both menisci was similar (2.444 vs. 2.438 ml; p = 0.92), the LM displayed larger tibial and femoral surface areas (p < 0.05) and a smaller maximal (7.2 ± 1.0 vs. 7.7 ± 1.1 mm; p < 0.01) and mean thickness (2.7 ± 0.3 vs. 2.8 ± 0.3 mm; p < 0.001) than the medial one. Also, the LM displayed less (physiological) extrusion than the medial one. These data may guide strategies for meniscal tissue engineering and transplantation aiming to restore normal joint conditions. PMID:21709397

  20. 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

  1. 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

  2. Repair of articular cartilage and meniscal tears by photoactive dyes: in-vivo study

    NASA Astrophysics Data System (ADS)

    Judy, Millard M.; Jackson, Robert W.; Nosir, Hany R.; Matthews, James Lester; Lewis, David E.; Utecht, Ronald E.; Yuan, Dongwu

    1996-12-01

    We describe healing results of our 6 month study of a repair procedure which evokes the healing response in meniscal tears and partial thickness defects in articular cartilage by a non-thermal tissue sparing photochemical weld using 1,8-naphthalimide dyes. Welds of incisional flaps in adult sheep meniscus and femoral articular cartilage were made using the dye MBM Gold 012011012 at 12 mM in PBS, 457.9nm Argon ion laser radiation at 800 mW/cm2, 7.5 minutes with approximately 1 kg/cm2 externally applied pressure. Gross appearance of tissues in all welded knees appeared normal. Hematoxylin and eosin stained sections disclosed close bonding of welded areas and continuing healing response as cellular recruitment.

  3. The effects of lasers and electrosurgical devices on human meniscal tissue.

    PubMed

    Sherk, H H; Black, J D; Prodoehl, J A; Diven, J

    1995-01-01

    The purpose of this study was to evaluate the effects of various laser wavelengths on human meniscal tissue in vitro and to compare them with the effects of electrosurgical devices. The carbon dioxide (CO2) laser produced the best cutting and ablating effects among the infrared lasers, although the contact neodymium:yttrium-aluminum-garnet (Nd:YAG) and holmium:YAG (Ho:YAG)lasers were nearly as satisfactory, offering the additional advantage of fiberoptic capability and the ability to be used in saline. The free-beam Nd:YAG laser and coagulation mode electrosurgical device produced unacceptably severe thermal changes. The excimer laser at 308 nm produced the best tissue effect and caused no detectable adjacent thermal change in the tissue. PMID:7641430

  4. Dissociated Roles for the Lateral and Medial Septum in Elemental and Contextual Fear Conditioning

    ERIC Educational Resources Information Center

    Calandreau, Ludovic; Jaffard, Robert; Desmedt, Aline

    2007-01-01

    Extensive evidence indicates that the septum plays a predominant role in fear learning, yet the direction of this control is still a matter of debate. Increasing data suggest that the medial (MS) and lateral septum (LS) would be differentially required in fear conditioning depending on whether a discrete conditional stimulus (CS) predicts, or not,…

  5. Dissociable Contributions within the Medial Temporal Lobe to Encoding of Object-Location Associations

    ERIC Educational Resources Information Center

    Sommer, Tobias; Rose, Michael; Glascher, Jan; Wolbers, Thomas; Buchel, Christian

    2005-01-01

    The crucial role of the medial temporal lobe (MTL) in episodic memory is well established. Although there is little doubt that its anatomical subregions--the hippocampus, peri-, entorhinal and parahippocampal cortex (PHC)--contribute differentially to mnemonic processes, their specific functions in episodic memory are under debate. Data from…

  6. Thickness of the Meniscal Lamellar Layer: Correlation with Indentation Stiffness and Comparison of Normal and Abnormally Thick Layers by Using Multiparametric Ultrashort Echo Time MR Imaging.

    PubMed

    Choi, Ja-Young; Biswas, Reni; Bae, Won C; Healey, Robert; Im, Michael; Statum, Sheronda; Chang, Eric Y; Du, Jiang; Bydder, Graeme M; D'Lima, Darryl; Chung, Christine B

    2016-07-01

    Purpose To determine the relationship between lamellar layer thickness on ultrashort echo time (UTE) magnetic resonance (MR) images and indentation stiffness of human menisci and to compare quantitative MR imaging values between two groups with normal and abnormally thick lamellar layers. Materials and Methods This was a HIPAA-compliant, institutional review board-approved study. Nine meniscal pieces were obtained from seven donors without gross meniscal pathologic results (mean age, 57.4 years ± 14.5 [standard deviation]). UTE MR imaging and T2, UTE T2*, and UTE T1ρ mapping were performed. The presence of abnormal lamellar layer thickening was determined and thicknesses were measured. Indentation testing was performed. Correlation between the thickness and indentation stiffness was assessed, and mean quantitative MR imaging values were compared between the groups. Results Thirteen normal lamellar layers had mean thickness of 232 μm ± 85 and indentation peak force of 1.37 g ± 0.87. Four abnormally thick lamellar layers showed mean thickness of 353.14 μm ± 98.36 and peak force 0.72 g ± 0.31. In most cases, normal thicknesses showed highly positive correlation with the indentation peak force (r = 0.493-0.912; P < .001 to .05). However, the thickness in two abnormal lamellar layers showed highly negative correlation (r = -0.90, P < .001; and r = -0.23, P = .042) and no significant correlation in the others. T2, UTE T2*, and UTE T1ρ values in abnormally thick lamellar layers were increased compared with values in normal lamellar layers, although only the UTE T2* value showed significant difference (P = .010). Conclusion Variation of lamellar layer thickness in normal human menisci was evident on two-dimensional UTE images. In normal lamellar layers, thickness is highly and positively correlated with surface indentation stiffness. UTE T2* values may be used to differentiate between normal and abnormally thickened lamellar layers. (©) RSNA, 2016. PMID:26829523

  7. The place of arthrography in the diagnosis and management of meniscal injuries--a 6-year review.

    PubMed Central

    Evans, S E; Chandy, J; Aldridge, M J

    1991-01-01

    Four hundred and eighty-seven consecutive knee arthrograms, performed over a 6-year period, are reviewed. Their accuracy is compared with arthroscopy and, where appropriate, with arthrotomy. The increasing accuracy of arthrography has resulted in the acceptance of this method of imaging as a useful and accurate means of examining meniscal injuries in the knee. This has led to far fewer surgical procedures and an overall saving of resources. PMID:2013891

  8. Mass media-led antismoking campaign can remove the education gap in quitting behavior.

    PubMed Central

    Macaskill, P; Pierce, J P; Simpson, J M; Lyle, D M

    1992-01-01

    This study investigated whether the effective mass media-led antismoking campaigns in Australia had the traditional differential effect across educational levels. Our population surveys included random samples of 12,851 people before the campaign and 11,609 several years after the campaign had started. No statistically significant differences were found in quitting across education levels in three of the four subgroups. Mass media-led antismoking campaigns may play an important role in getting the antismoking message to the less educated. PMID:1536344

  9. Fibrochondrogenic potential of synoviocytes from osteoarthritic and normal joints cultured as tensioned bioscaffolds for meniscal tissue engineering in dogs

    PubMed Central

    Bobe, Gerd; Duesterdieck-Zellmer, Katja F.

    2014-01-01

    Meniscal tears are a common cause of stifle lameness in dogs. Use of autologous synoviocytes from the affected stifle is an attractive cell source for tissue engineering replacement fibrocartilage. However, the diseased state of these cells may impede in vitro fibrocartilage formation. Synoviocytes from 12 osteoarthritic (“oaTSB”) and 6 normal joints (“nTSB”) were cultured as tensioned bioscaffolds and compared for their ability to synthesize fibrocartilage sheets. Gene expression of collagens type I and II were higher and expression of interleukin-6 was lower in oaTSB versus nTSB. Compared with nTSB, oaTSB had more glycosaminoglycan and alpha smooth muscle staining and less collagen I and II staining on histologic analysis, whereas collagen and glycosaminoglycan quantities were similar. In conclusion, osteoarthritic joint—origin synoviocytes can produce extracellular matrix components of meniscal fibrocartilage at similar levels to normal joint—origin synoviocytes, which makes them a potential cell source for canine meniscal tissue engineering. PMID:25289180

  10. 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

  11. 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

  12. 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

  13. 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

  14. Meniscal Allograft Transplantation Does Not Prevent or Delay Progression of Knee Osteoarthritis

    PubMed Central

    Byttebier, Paul; Eeckhoudt, Annelies; Victor, Jan

    2016-01-01

    Background Meniscal tears are common knee injuries. Meniscal allograft transplantation (MAT) has been advocated to alleviate symptoms and delay osteoarthritis (OA) after meniscectomy. We investigated (1) the long-term outcome of MAT as a treatment of symptomatic meniscectomy, (2) most important factors affecting survivorship and (3) OA progression. Methods From 1989 till 2013, 329 MAT were performed in 313 patients. Clinical and radiographic results and MAT survival were evaluated retrospectively. Failure was defined as conversion to knee arthroplasty (KA) or total removal of the MAT. Results Mean age at surgery was 33 years (15–57); 60% were males. No-to-mild cartilage damage was found in 156 cases, moderate-to-severe damage in 130. Simultaneous procedures in 118 patients included cartilage procedures, osteotomy or ACL-reconstruction. At a mean follow-up of 6.8 years (0.2–24.3years), 5 patients were deceased and 48 lost (14.6%), 186 MAT were in situ (56.5%) whilst 90 (27.4%) had been removed, including 63 converted to a KA (19.2%). Cumulative allograft survivorship was 15.1% (95% CI:13.9–16.3) at 24.0 years. In patients <35 years at surgery, survival was significantly better (24.1%) compared to ≥35 years (8.0%) (p = 0.017). In knees with no-to-mild cartilage damage more allografts survived (43.0%) compared to moderate-to-severe damage (6.6%) (p = 0.003). Simultaneous osteotomy significantly deteriorated survival (0% at 24.0 years) (p = 0.010). 61% of patients underwent at least one additional surgery (1–11) for clinical symptoms after MAT. Consecutive radiographs showed significant OA progression at a mean of 3.8 years (p<0.0001). Incremental Kellgren-Lawrence grade was +1,1 grade per 1000 days (2,7yrs). Conclusions MAT did not delay or prevent tibiofemoral OA progression. 19.2% were converted to a knee prosthesis at a mean of 10.3 years. Patients younger than 35 with no-to-mild cartilage damage may benefit from MAT for relief of symptoms (survivorship

  15. 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

  16. 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,…

  17. [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

  18. 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

  19. 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…

  20. Biomedical-grade, high mannuronic acid content (BioMVM) alginate enhances the proteoglycan production of primary human meniscal fibrochondrocytes in a 3-D microenvironment

    PubMed Central

    Rey-Rico, Ana; Klich, Angelique; Cucchiarini, Magali; Madry, Henning

    2016-01-01

    Alginates are important hydrogels for meniscus tissue engineering as they support the meniscal fibrochondrocyte phenotype and proteoglycan production, the extracellular matrix (ECM) component chiefly responsible for its viscoelastic properties. Here, we systematically evaluated four biomedical- and two nonbiomedical-grade alginates for their capacity to provide the best three-dimensional (3-D) microenvironment and to support proteoglycan synthesis of encapsulated human meniscal fibrochondrocytes in vitro. Biomedical-grade, high mannuronic acid alginate spheres (BioLVM, BioMVM) were the most uniform in size, indicating an effect of the purity of alginate on the shape of the spheres. Interestingly, the purity of alginates did not affect cell viability. Of note, only fibrochondrocytes encapsulated in BioMVM alginate produced and retained significant amounts of proteoglycans. Following transplantation in an explant culture model, the alginate spheres containing fibrochondrocytes remained in close proximity with the meniscal tissue adjacent to the defect. The results reveal a promising role of BioMVM alginate to enhance the proteoglycan production of primary human meniscal fibrochondrocytes in a 3-D hydrogel microenvironment. These findings have significant implications for cell-based translational studies aiming at restoring lost meniscal tissue in regions containing high amounts of proteoglycans. PMID:27302206

  1. Isolated tear of the tendon to the medial head of gastrocnemius presenting as a painless lump in the calf

    PubMed Central

    Watura, Christopher; Harries, William

    2009-01-01

    We report on a case of isolated tear of the medial head of gastrocnemius tendon. The patient presented with a painless lump in the right calf and denied any prior history of trauma or strain to the leg. A longitudinal split of the tendon was demonstrated at ultrasound and magnetic resonance imaging (MRI). There were no other abnormalities and the gastrocnemius muscle was normal. There are no reports in the literature of isolated gastrocnemius tendon tear. To date the calf muscle complex injury described in this area is tearing of the medial head of gastrocnemius muscle, sometimes referred to as “tennis leg”. We conclude that an isolated tear of the tendon to the medial head of gastrocnemius should be considered in the differential diagnosis of a lump or swelling in the upper medial area of the calf and we recommend ultrasound or MRI as the investigations of choice. PMID:21687013

  2. 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

  3. 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

  4. 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

  5. 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

  6. AN ALTERNATIVE APPROACH TO THE TREATMENT OF MENISCAL PATHOLOGIES: A CASE SERIES ANALYSIS OF THE MULLIGAN CONCEPT “SQUEEZE” TECHNIQUE

    PubMed Central

    Richmond, Amy; Sanchez, Belinda; Stevenson, Valerie; Baker, Russell T.; May, James; Nasypany, Alan; Reordan, Don

    2016-01-01

    ABSTRACT Background Partial meniscectomy does not consistently produce the desired positive outcomes intended for meniscal tears lesions; therefore, a need exists for research into alternatives for treating symptoms of meniscal tears. The purpose of this case series was to examine the effect of the Mulligan Concept (MC) “Squeeze” technique in physically active participants who presented with clinical symptoms of meniscal tears. Description of Cases The MC “Squeeze” technique was applied in five cases of clinically diagnosed meniscal tears in a physically active population. The Numeric Pain Rating Scale (NRS), the Patient Specific Functional Scale (PSFS), the Disability in the Physically Active (DPA) Scale, and the Knee injury and Osteoarthritis Outcomes Score (KOOS) were administered to assess participant pain level and function. Outcomes Statistically significant improvements were found on cumulative NRS (p ≤ 0.001), current NRS (p ≤ 0.002), PSFS (p ≤ 0.003), DPA (p ≤ 0.019), and KOOS (p ≤ 0.002) scores across all five participants. All participants exceeded the minimal clinically important difference (MCID) on the first treatment and reported an NRS score and current pain score of one point or less at discharge. The MC “Squeeze” technique produced statistically and clinically significant changes across all outcome measures in all five participants. Discussion The use of the MC “Squeeze” technique in this case series indicated positive outcomes in five participants who presented with meniscal tear symptoms. Of importance to the athletic population, each of the participants continued to engage in sport activity as tolerated unless otherwise required during the treatment period. The outcomes reported in this case series exceed those reported when using traditional conservative therapy and the return to play timelines for meniscal tears treated with partial meniscectomies. Levels of Evidence Level 4 PMID:27525181

  7. Guanfacine promotes neuronal survival in medial prefrontal cortex under hypobaric hypoxia.

    PubMed

    Kauser, H; Sahu, S; Panjwani, U

    2016-04-01

    High altitude hypobaric hypoxia (HH) affects prefrontal cognitive and executive functions. Guanfacine, alpha 2A adrenoceptor agonist ameliorates the neurological outcomes of high altitude exposure and associated prefrontal neurodegeneration. However, the molecular mechanism underlying the neuroprotective effect of guanfacine following HH remains elusive. Altered balance of pro and anti-apoptotic proteins have been implicated in the beneficial effect of guanfacine to enhance neuronal survival. We examined the effects of guanfacine on expression of some key neurotropic and cytoskeletal proteins following HH. Male rats were exposed to simulated altitude of 7620 m and received an intramuscular injection of either saline or guanfacine at a dose of 1mg/kg for 7 consecutive days. Differential expression of desired proteins was evaluated in layer II of medial prefrontal cortex (PFC) by biochemical and immunohistochemical assays. Guanfacine treatment significantly increased the expression of BDNF in layer II of the medial PFC during normoxia and HH. Moreover, there was a negative correlation of this neurotropic factor with neurodegeneration of pyramidal cells present in this layer of medial PFC. We found a significant decrease in Caspase3 and Bax while a significant increase in Bcl2 with guanfacine treatment during HH. Further, change in Bax to Bcl2 ratio was in correlation with Caspase3 expression in layer II of the medial PFC, indicating that Caspase3 is responsible for Bcl2 cleavage and hence modulation of apoptosis. Guanfacine treatment induced a marked and significant increase in MAP2 and Spinophilin expression in dendritic arbors and spines respectively. Interestingly, alteration in these cytoskeletal proteins was accompanied by simultaneous changes in morphological parameters of dendrites in layer II of medial PFC. Guanfacine modulates the neurotropic, cytoskeletal, pro and anti-apoptotic protein expression in medial PFC under HH and therefore serve as a

  8. 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

  9. 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

  10. 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

  11. [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

  12. 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.

  13. 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

  14. 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

  15. Wrisberg variant of the discoid lateral meniscus with flipped meniscal fragments simulating bucket-handle tear: MRI and arthroscopic correlation.

    PubMed

    Yue, Brian W; Gupta, Anil K; Moorman, Claude T; Garrett, William E; Helms, Clyde A

    2011-08-01

    An MRI diagnosis of the Wrisberg variant discoid lateral meniscus should be considered in patients presenting with an anteriorly flipped posterior horn fragment without a definable peripheral rim. We present four cases discovered on arthroscopy that were thought to resemble bucket-handle tears on preoperative MRI. Posterior hypermobility poses a surgical challenge as excessive debridement without careful attention to underlying meniscal morphology may lead to further instability. Although this diagnosis can be difficult to make on MRI, alerting the orthopedic surgeon preoperatively may influence repair technique and meniscus conservation. PMID:21340450

  16. Intra-articular Patterns of Bucket Handle Meniscal Tears and Its Relation to Reducibility

    PubMed Central

    Lim, Hong Chul; Bae, Ji-Hoon; Kim, Taik-Sun; Yang, Jae-Hyuk; Park, Sung-Chul

    2012-01-01

    Background The purpose of this study was to assess the intra-articular patterns in the rotational deformities of bucket handle meniscal tears (BHMTs) based on arthroscopic findings and their clinical relevance. Methods From 2004 to 2009, 42 patients with a BHMT diagnosed by magnetic resonance imaging underwent arthroscopic surgery. The arthroscopic data (all procedures were recorded) were evaluated retrospectively, and BHMTs were classified according to the rotational directions of centrally displaced fragments. To assess the reliability of the agreement in this classification, 2 orthopedic surgeons re-classified BHMTs, 1 week after first trial. Intra- and interobserver reliabilities were assessed using kappa statistics. In addition, we address specific tear patterns, associated anterior cruciate ligament injury, medio-lateral difference, reducibility, chronicity, and reparability. Results Most of the tears could be categorized into one of 3 morphologic patterns. Of the tears, 4.8% could not be categorized. BHMTs were classified, based on the rotational directions of centrally displaced fragments, as follows; the upward rotation group (type 1), the downward rotation group (type 2) and the reverse group (type 3). The most common intra-articular pattern was type 1 (29 patients, 69%). The occurrence of the other patterns was: type 2 in 7 patients (16.7%), type 3 in 4 patients (9.5%); we were not able to make a classification of type in 2 patients (4.8%). Intra-observer reliability was 0.86 in terms of kappa statistics, which implies almost perfect agreement. Mean interobserver reliability (0.73) showed substantial agreement. Type 1 and 2 tears were easily reduced, whereas all type 3 tears (4/4) needed additional procedures to achieve reduction. Conclusions Based on arthroscopic findings, we describe a comprehensive BHMT classification scheme that encompasses 95.2% of all tears. Tear type was correlated with reducibility. PMID:22662298

  17. 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

  18. Investigation of the Regenerative Capacity of an Acellular Porcine Medial Meniscus for Tissue Engineering Applications

    PubMed Central

    Ingram, Joanne; Fisher, John; Ingham, Eileen

    2011-01-01

    Previously, we have described the development of an acellular porcine meniscal scaffold. The aims of this study were to determine the immunocompatibility of the scaffold and capacity for cellular attachment and infiltration to gain insight into its potential for meniscal repair and replacement. Porcine menisci were decellularized by exposing the tissue to freeze–thaw cycles, incubation in hypotonic tris buffer, 0.1% (w/v) sodium dodecyl sulfate in hypotonic buffer plus protease inhibitors, nucleases, hypertonic buffer followed by disinfection using 0.1% (v/v) peracetic, and final washing in phosphate-buffered saline. In vivo immunocompatibility was assessed after implantation of the acellular meniscal scaffold subcutaneously into galactosyltransferase knockout mice for 3 months in comparison to fresh and acellular tissue treated with α-galactosidase (negative control). The cellular infiltrates in the explants were assessed by histology and characterized using monoclonal antibodies against: CD3, CD4, CD34, F4/80, and C3c. Static culture was used to assess the potential of acellular porcine meniscal scaffold to support the attachment and infiltration of primary human dermal fibroblasts and primary porcine meniscal cells in vitro. The explants were surrounded by capsules that were more pronounced for the fresh meniscal tissue compared to the acellular tissues. Cellular infiltrates compromised mononuclear phagocytes, CD34-positive cells, and nonlabeled fibroblastic cells. T-lymphocytes were sparse in all explanted tissue types and there was no evidence of C3c deposition. The analysis revealed an absence of a specific immune response to all of the implanted tissues. Acellular porcine meniscus was shown to be capable of supporting the attachment and infiltration of primary human fibroblasts and primary porcine meniscal cells. In conclusion, acellular porcine meniscal tissue exhibits excellent immunocompatibility and potential for cellular regeneration in the longer

  19. The effect of hip joint muscle exercise on muscle strength and balance in the knee joint after meniscal injury.

    PubMed

    Park, Sun Ja; Kim, Young Mi; Kim, Ha Roo

    2016-04-01

    [Purpose] This study aimed to evaluate the effect of hip muscle strengthening on muscle strength and balance in the knee joint after a meniscal injury. [Subjects and Methods] This randomized control study enrolled 24 patients who had undergone arthroscopic treatment after a meniscal injury and began a rehabilitative exercise program 8 weeks after surgery. Subjects were divided into 2 groups of 12 subjects each: gluteus medius resistance exercise group and control group. This study investigated muscle strength and balance in the knee joint flexor, extensor, and abductor during an 8-week period. [Results] Measurements of knee extensor muscle strength revealed no significant difference between the control group and the experimental group. Measurements of abductor muscle strength, however, identified a significant difference between the 2 groups. The groups did not differ significantly with regard to balance measurements. [Conclusion] The results of this study suggest that this subject should be approached in light of the correlation between the hip abductor and injury to the lower extremities. PMID:27190461

  20. The effect of hip joint muscle exercise on muscle strength and balance in the knee joint after meniscal injury

    PubMed Central

    Park, Sun Ja; Kim, Young Mi; Kim, Ha Roo

    2016-01-01

    [Purpose] This study aimed to evaluate the effect of hip muscle strengthening on muscle strength and balance in the knee joint after a meniscal injury. [Subjects and Methods] This randomized control study enrolled 24 patients who had undergone arthroscopic treatment after a meniscal injury and began a rehabilitative exercise program 8 weeks after surgery. Subjects were divided into 2 groups of 12 subjects each: gluteus medius resistance exercise group and control group. This study investigated muscle strength and balance in the knee joint flexor, extensor, and abductor during an 8-week period. [Results] Measurements of knee extensor muscle strength revealed no significant difference between the control group and the experimental group. Measurements of abductor muscle strength, however, identified a significant difference between the 2 groups. The groups did not differ significantly with regard to balance measurements. [Conclusion] The results of this study suggest that this subject should be approached in light of the correlation between the hip abductor and injury to the lower extremities. PMID:27190461

  1. Pilot Study of Response Inhibition and Error Processing in the Posterior Medial Prefrontal Cortex in Healthy Youth

    ERIC Educational Resources Information Center

    Fitzgerald, Kate Dimond; Zbrozek, Christopher D.; Welsh, Robert C.; Britton, Jennifer C.; Liberzon, Israel; Taylor, Stephan F.

    2008-01-01

    Background: Recent neuroimaging work suggests that inhibitory and error processing in healthy adults share overlapping, but functionally distinct neural circuitries within the posterior medial frontal cortex (pMFC); however, it remains unknown whether the pMFC is differentially engaged by response inhibition compared to error commission in the…

  2. A novel hypothesis: the application of platelet-rich plasma can promote the clinical healing of white-white meniscal tears.

    PubMed

    Wei, Li-Cheng; Gao, Shu-Guang; Xu, Mai; Jiang, Wei; Tian, Jian; Lei, Guang-Hua

    2012-08-01

    The white-white tears (meniscus lesion completely in the avascular zone) are without blood supply and theoretically cannot heal. Basal research has demonstrated that menisci are unquestionably important in load bearing, load redistribution, shock absorption, joint lubrication and the stabilization of the knee joint. It has been proven that partial or all-meniscusectomy results in an accelerated degeneration of cartilage and an increased rate of early osteoarthritis. Knee surgeons must face the difficult decision of removing or, if possible, retaining the meniscus; if it is possible to retain the meniscus, surgeons must address the difficulties of meniscal healing. Some preliminary approaches have progressed to improve meniscal healing. However, the problem of promoting meniscal healing in the avascular area has not yet been resolved. The demanding nature of the approach as well as its low utility and efficacy has impeded the progress of these enhancement techniques. Platelet-rich plasma (PRP) is a platelet concentration derived from autologous blood. In recent years, PRP has been used widely in preclinical and clinical applications for bone regeneration and wound healing. Therefore, we hypothesize that the application of platelet-rich plasma for white-white meniscal tears will be a simple and novel technique of high utility in knee surgery. PMID:22847210

  3. Content representation in the human medial temporal lobe.

    PubMed

    Liang, Jackson C; Wagner, Anthony D; Preston, Alison R

    2013-01-01

    Current theories of medial temporal lobe (MTL) function focus on event content as an important organizational principle that differentiates MTL subregions. Perirhinal and parahippocampal cortices may play content-specific roles in memory, whereas hippocampal processing is alternately hypothesized to be content specific or content general. Despite anatomical evidence for content-specific MTL pathways, empirical data for content-based MTL subregional dissociations are mixed. Here, we combined functional magnetic resonance imaging with multiple statistical approaches to characterize MTL subregional responses to different classes of novel event content (faces, scenes, spoken words, sounds, visual words). Univariate analyses revealed that responses to novel faces and scenes were distributed across the anterior-posterior axis of MTL cortex, with face responses distributed more anteriorly than scene responses. Moreover, multivariate pattern analyses of perirhinal and parahippocampal data revealed spatially organized representational codes for multiple content classes, including nonpreferred visual and auditory stimuli. In contrast, anterior hippocampal responses were content general, with less accurate overall pattern classification relative to MTL cortex. Finally, posterior hippocampal activation patterns consistently discriminated scenes more accurately than other forms of content. Collectively, our findings indicate differential contributions of MTL subregions to event representation via a distributed code along the anterior-posterior axis of MTL that depends on the nature of event content. PMID:22275474

  4. Simultaneous bicompartmental bucket-handle meniscal tears with intact anterior cruciate ligament: a case report

    PubMed Central

    2010-01-01

    Introduction Bucket handle tear of the menisci is a common type of lesion resulting from injury to the knee joint. Bucket handle injury of both menisci in almost all cases is associated with a lesion to either the anterior or the posterior cruciate ligament of the knee joint. We describe a case of acute bucket-handle tear of the medial and lateral menisci with intact anterior and posterior cruciate ligaments in a dancer. To the best of our knowledge, there are no previous reports of this type of injury in the literature. Case presentation A 28-year-old Caucasian Greek woman presented to the emergency department after sustaining an injury to her right knee during dancing. An MRI evaluation demonstrated tears in both menisci of the right knee, while the anterior and posterior cruciate ligaments were found to be intact. A partial medial and lateral meniscectomy was then performed. At a follow-up examination six months after her injury, clinical tests demonstrated that our patient's right knee was stable, had a full range of motion and had no tenderness. She was satisfied with the outcome of the operation and returned to her pre-injury activities. Conclusion We present the first case in the literature that describes a combined bucket-handle injury of both the medial and lateral menisci with an intact anterior cruciate ligament. The clinical examination of the anterior cruciate ligament was unremarkable, with no signs of deficiency or rupture. The posterior cruciate ligament was also intact. On magnetic resonance imaging, the ligaments were visualised as intact in all their length. These findings were confirmed by arthroscopic evaluation. PMID:20181059

  5. Development and Characterization of UHMWPE Fiber-Reinforced Hydrogels For Meniscal Replacement

    NASA Astrophysics Data System (ADS)

    Holloway, Julianne Leigh

    Meniscal tears are the most common orthopedic injuries to the human body. The current treatment of choice, however, is a partial meniscectomy that leads to osteoarthritis proportional to the amount of tissue removed. As a result, there is a significant clinical need to develop materials capable of restoring the biomechanical contact stress distribution to the knee after meniscectomy and preventing the onset of osteoarthritis. In this work, a fiber-reinforced hydrogel-based synthetic meniscus was developed that allows for tailoring of the mechanical properties and molding of the implant to match the size, shape, and property distribution of the native tissue. Physically cross-linked poly(vinyl alcohol) (PVA) hydrogels were reinforced with ultrahigh molecular weight polyethylene (UHMWPE) fibers and characterized in compression (0.1-0.8 MPa) and tension (0.1-250 MPa) showing fine control over mechanical properties within the range of the human meniscus. Morphology and crystallinity analysis of PVA hydrogels showed increases in crystallinity and PVA densification, or phase separation, with freeze-thaw cycles. A comparison of freeze-thawed and aged, physically cross-linked hydrogels provided insight on both crystallinity and phase separation as mechanisms for PVA gelation. Results indicated both mechanisms independently contributed to hydrogel modulus for freeze-thawed hydrogels. In vitro swelling studies were performed using osmotic solutions to replicate the swelling pressure present in the knee. Minimal swelling was observed for hydrogels with a PVA concentration of 30-35 wt%, independently of hydrogel freeze-thaw cycles. This allows for independent tailoring of hydrogel modulus and pore structure using freeze-thaw cycles and swelling behavior using polymer concentration to match a wide range of properties needed for various soft tissue applications. The UHMWPE-PVA interface was identified as a significant weakness. To improve interfacial adhesion, a novel

  6. 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

  7. Medial HOXA genes demarcate haematopoietic stem cell fate during human development.

    PubMed

    Dou, Diana R; Calvanese, Vincenzo; Sierra, Maria I; Nguyen, Andrew T; Minasian, Arazin; Saarikoski, Pamela; Sasidharan, Rajkumar; Ramirez, Christina M; Zack, Jerome A; Crooks, Gay M; Galic, Zoran; Mikkola, Hanna K A

    2016-06-01

    Pluripotent stem cells (PSCs) may provide a potential source of haematopoietic stem/progenitor cells (HSPCs) for transplantation; however, unknown molecular barriers prevent the self-renewal of PSC-HSPCs. Using two-step differentiation, human embryonic stem cells (hESCs) differentiated in vitro into multipotent haematopoietic cells that had the CD34(+)CD38(-/lo)CD90(+)CD45(+)GPI-80(+) fetal liver (FL) HSPC immunophenotype, but exhibited poor expansion potential and engraftment ability. Transcriptome analysis of immunophenotypic hESC-HSPCs revealed that, despite their molecular resemblance to FL-HSPCs, medial HOXA genes remained suppressed. Knockdown of HOXA7 disrupted FL-HSPC function and caused transcriptome dysregulation that resembled hESC-derived progenitors. Overexpression of medial HOXA genes prolonged FL-HSPC maintenance but was insufficient to confer self-renewal to hESC-HSPCs. Stimulation of retinoic acid signalling during endothelial-to-haematopoietic transition induced the HOXA cluster and other HSC/definitive haemogenic endothelium genes, and prolonged HSPC maintenance in culture. Thus, medial HOXA gene expression induced by retinoic acid signalling marks the establishment of the definitive HSPC fate and controls HSPC identity and function. PMID:27183470

  8. 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

  9. 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

  10. 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

  11. Free synovium promotes meniscal healing. Synovium, muscle and synthetic mesh compared in dogs.

    PubMed

    Shirakura, K; Niijima, M; Kobuna, Y; Kizuki, S

    1997-02-01

    We studied the effect of free synovium on the healing of tears in the avascular portion of the menisci in dogs. A longitudinal incision was made in the medial meniscus. In 35 dogs, a free graft of synovium was inserted into the tear and sutured. In 10 dogs, a free graft of quadriceps muscle was used. In 10 dogs, a Dacron mesh was inserted. In the contralateral knee, the tear was sutured without implantation as a control. 2, 4, 6, 8, and 12 weeks after the operation, the menisci were dissected. 11 of the 35 with free synovium were healed. The menisci with muscle grafts, those with Dacron mesh and those in the control group did not heal. Histology showed that tears were repaired with fibrous tissue. Microangiography showed that capillaries grew from the periphery, but they did not reach the tear. PMID:9057568

  12. 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.

  13. Applying Electrospun Gelatin/Poly(lactic acid-co-glycolic acid) Bilayered Nanofibers to Fabrication of Meniscal Tissue Engineering Scaffold.

    PubMed

    Li, Peng; Zhang, Weiguo; Yu, Hongquan; Zheng, Lianjie; Yang, Liang; Liu, Gang; Sheng, Chenchen; Gui, Haoran; Ni, Shuo; Li, Pengsheng; Shi, Feng

    2016-05-01

    The menisci are fibrocartilaginous tissues composed primarily of an interlacing network of collagen fibers with nanoscale diameter. Electrospinning is a suitable process of producing nanoscale fibers that mimic collagen fibers. In this study, a bilayered scaffold (group B), which consists of a gelatin nanofiber mesh and a PLGA nanofiber mesh, has been fabricated through an electrospinning method. At the same time, we electrospun pure PLGA fibrous mesh (group A) and gelatin/PLGA composite fibrous mesh (group C) as control groups. In order to compare all scaffold morphologies, the scaffolds were imaged by SEM and some parameters were measured and analyzed as following: Diameters of fibrils are from the smallest of less than average 0.14 μm for group C to the biggest of nearly average 0.38 μm for group B. The scaffolds pore diameters are from average 4.9 μm for group A to average 11.2 μm for group B. Porosity rates show that the group B has the highest porosity rate at about 91%. The scaffolds' properties were compared and analyzed, including hydrophilicity property (water contact angle) and mechanical properties (tensile strength). The results of water contact angle showed the group B is the most hydrophil among the groups. The results of tensile strength showed the tensile strength of group C is the weakest among the groups. All the results showed significant differences between the groups. Finally, in vitro, the meniscal cells derived from New Zealand white rabbits menisci were seeded in the scaffolds. We observed the cells proliferation behavior in the scaffolds. All above demonstrates that a bi-layered gelatin/PLGA scaffold reveals not only concurrent effects of mechanics and cytocompatibility in a fibrous context, but also a promising scaffold for future meniscal repair strategies. PMID:27483813

  14. 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

  15. Basket-Weave Technique for Medial Patellofemoral Ligament Reconstruction.

    PubMed

    Kodkani, Pranjal S

    2015-06-01

    The anatomy of the medial patellofemoral ligament (MPFL) has been well defined, with parts of its uppermost fibers having a soft-tissue insertion onto the vastus intermedius. Bone tunnels and implants on the patellar side therefore cannot replicate this anatomic construct precisely. Because of implants and tunnels, complications have been reported with bone tunnel fracture. Similarly, on the femoral side, rigid fixation with implants can result in over-constraint with compromised results. Moreover, bone tunnels cannot be used in skeletally immature cases. To overcome issues related to bone tunneling and implants, as well as to reconstruct the MPFL in a precise anatomic manner, an all-soft-tissue fixation technique was devised. Bony landmarks were used as reference points instead of radiologic markers to achieve a more precise construct and to eliminate intraoperative radiography. Hamstring graft was used to reconstruct the MPFL. Special suturing techniques were used to achieve optimal graft fixation with minimal suture knots. A special tissue elevator-suture passer device was designed to facilitate graft passage and ease in performing the procedure. This technique permits differential tensioning, and therefore one achieves stability throughout the range of motion. PMID:26258044

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

    PubMed

    Wang, Wei-Chun; Giovanello, Kelly S

    2016-06-01

    Considerable neuropsychological and neuroimaging work indicates that the medial temporal lobes are critical for both item and relational memory retrieval. However, there remain outstanding issues in the literature, namely the extent to which medial temporal lobe regions are differentially recruited during incidental and intentional retrieval of item and relational information, and the extent to which aging may affect these neural substrates. The current fMRI study sought to address these questions; participants incidentally encoded word pairs embedded in sentences and incidental item and relational retrieval were assessed through speeded reading of intact, rearranged, and new word-pair sentences, while intentional item and relational retrieval were assessed through old/new associative recognition of a separate set of intact, rearranged, and new word pairs. Results indicated that, in both younger and older adults, anterior hippocampus and perirhinal cortex indexed incidental and intentional item retrieval in the same manner. In contrast, posterior hippocampus supported incidental and intentional relational retrieval in both age groups and an adjacent cluster in posterior hippocampus was recruited during both forms of relational retrieval for older, but not younger, adults. Our findings suggest that while medial temporal lobe regions do not differentiate between incidental and intentional forms of retrieval, there are distinct roles for anterior and posterior medial temporal lobe regions during retrieval of item and relational information, respectively, and further indicate that posterior regions may, under certain conditions, be over-recruited in healthy aging. © 2016 Wiley Periodicals, Inc. PMID:26928884

  17. Maturational alterations in constitutive activity of medial prefrontal cortex kappa-opioid receptors in Wistar rats.

    PubMed

    Sirohi, Sunil; Walker, Brendan M

    2015-11-01

    Opioid receptors can display spontaneous agonist-independent G-protein signaling (basal signaling/constitutive activity). While constitutive κ-opioid receptor (KOR) activity has been documented in vitro, it remains unknown if KORs are constitutively active in native systems. Using [(35) S] guanosine 5'-O-[gamma-thio] triphosphate coupling assay that measures receptor functional state, we identified the presence of medial prefrontal cortex KOR constitutive activity in young rats that declined with age. Furthermore, basal signaling showed an age-related decline and was insensitive to neutral opioid antagonist challenge. Collectively, the present data are first to demonstrate age-dependent alterations in the medial prefrontal cortex KOR constitutive activity in rats and changes in the constitutive activity of KORs can differentially impact KOR ligand efficacy. These data provide novel insights into the functional properties of the KOR system and warrant further consideration of KOR constitutive activity in normal and pathophysiological behavior. Opioid receptors exhibit agonist-independent constitutive activity; however, kappa-opioid receptor (KOR) constitutive activity has not been demonstrated in native systems. Our results confirm KOR constitutive activity in the medial prefrontal cortex (mPFC) that declines with age. With the ability to presynaptically inhibit multiple neurotransmitter systems in the mPFC, maturational or patho-logical alterations in constitutive activity could disrupt corticofugal glutamatergic pyramidal projection neurons mediating executive function. Regulation of KOR constitutive activity could serve as a therapeutic target to treat compromised executive function. PMID:26257334

  18. Study of the Clinical Outcome between Traumatic and Degenerative (non-traumatic) Meniscal Tears after Arthroscopic Surgery: A 4-Years Follow-up Study

    PubMed Central

    Ghislain, Nietiayurk Aminake; Wei, Ji-Nan

    2016-01-01

    Introduction The meniscus is a biconcave fibrocartilage in the knee joint interpose between the femoral condyles and tibial plateau; the meniscus has functions in load bearing, load transmission, shock absorption joint stability, joint lubrication, and joint congruity. Aim The aim of this study is to provide orthopeadic surgeon a base of reference in the choice of the optimal course of management for meniscal tears. Materials and Methods One hundred and seventeen patients met the criteria of inclusion for the present study. Patients were divided in two groups T and NT according to the presence of distinct previous traumatic events to the knees. Two subgroups were formed in each groups T and NT respectively at a mean follow up of 1 and 4 years. Postoperative clinical outcome were assessed using Lysholm scores and Rand SF-36 survey. Results One hundred and seventeen patients were included in the present study with 60(51.28%) patients in the traumatic group and 57(48.71%) in the degenerative group. 95(81.19%) patients in total were satisfied with their health status at end of follow up. The mean value of Lysholm scores at 1 year were respectively 85.25±8.78 for traumatic group and 86.38±12.14 for non-traumatic group and at 4 years were respectively 92.63±7.31 for traumatic group and 72.90±20.77 for non-traumatic group. According to Rand SF-36 health, traumatic group showed better improvements compare to non-traumatic group between 1 and 4 years after arthroscopic meniscus surgery. Conclusion A total of 95(81.19%) patients in total were satisfied with their health status at follow up, however, we found that arthroscopy as a treatment for meniscal tear have a relatively better mid-term clinical outcome for traumatic meniscal tears compare to non-traumatic/degenerative meniscal tears. PMID:27190905

  19. 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

  20. 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

  1. 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

  2. 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

  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. 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

  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. Transcriptomic Signature of the SHATTERPROOF2 Expression Domain Reveals the Meristematic Nature of Arabidopsis Gynoecial Medial Domain.

    PubMed

    Villarino, Gonzalo H; Hu, Qiwen; Manrique, Silvia; Flores-Vergara, Miguel; Sehra, Bhupinder; Robles, Linda; Brumos, Javier; Stepanova, Anna N; Colombo, Lucia; Sundberg, Eva; Heber, Steffen; Franks, Robert G

    2016-05-01

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

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

    PubMed Central

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

    2016-01-01

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

  8. 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

  9. 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

  10. 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

  11. Mechanical evaluation of poly(vinyl alcohol)-based fibrous composites as biomaterials for meniscal tissue replacement.

    PubMed

    Holloway, Julianne L; Lowman, Anthony M; Palmese, Giuseppe R

    2010-12-01

    In this study, poly(vinyl alcohol) (PVA) hydrogels were reinforced with ultrahigh molecular weight polyethylene (UHMWPE) and PP fibers and evaluated as potential nondegradable meniscal replacements. An investigation of hydrogel and composite mechanical properties indicates that fiber-reinforced PVA hydrogels could replicate the unique anisotropic modulus distribution present in the native meniscus; the most commonly damaged orthopedic tissue. More specifically, fibrous reinforcement successfully increased the tensile modulus of the biomaterial from 0.23±0.02MPa without any reinforcement to 258.1±40.1MPa at 29vol.% UHMWPE. Additionally, the molecular weight between cross-links, bound water and the microstructure of the PVA hydrogels were evaluated as a function of freeze-thaw cycles and polymer concentration to lend insight into the processes occurring during synthesis. These results suggest the presence of multiple mechanisms as causes for increasing hydrogel modulus with freeze-thaw cycling, including hydrogen bonding between amorphous and/or crystalline regions, and the formation of highly concentrated regions of mostly amorphous PVA chains. It is possible that the formation of regions with highly concentrated amounts of PVA increases the load-bearing ability of the hydrogels. PMID:20601243

  12. CT Arthrography and Virtual Arthroscopy in the Diagnosis of the Anterior Cruciate Ligament and Meniscal Abnormalities of the Knee Joint

    PubMed Central

    Lee, Whal; Kim, Ho Sung; Kim, Seok Jung; Kim, Hyung Ho; Chung, Jin Wook; Kang, Heung Sik; Choi, Ja-Young

    2004-01-01

    Objective To determine the diagnostic accuracy of CT arthrography and virtual arthroscopy in the diagnosis of anterior cruciate ligament and meniscus pathology. Materials and Methods Thirty-eight consecutive patients who underwent CT arthrography and arthroscopy of the knee were included in this study. The ages of the patients ranged from 19 to 52 years and all of the patients were male. Sagittal, coronal, transverse and oblique coronal multiplanar reconstruction images were reformatted from CT arthrography. Virtual arthroscopy was performed from 6 standard views using a volume rendering technique. Three radiologists analyzed the MPR images and two orthopedic surgeons analyzed the virtual arthroscopic images. Results The sensitivity and specificity of CT arthrography for the diagnosis of anterior cruciate ligament abnormalities were 87.5%-100% and 93.3-96.7%, respectively, and those for meniscus abnormalities were 91.7%-100% and 98.1%, respectively. The sensitivity and specificity of virtual arthroscopy for the diagnosis of anterior cruciate ligament abnormalities were 87.5% and 83.3-90%, respectively, and those for meniscus abnormalities were 83.3%-87.5% and 96.1-98.1%, respectively. Conclusion CT arthrography and virtual arthroscopy showed good diagnostic accuracy for anterior cruciate ligament and meniscal abnormalities. PMID:15064559

  13. Rab43 regulates the sorting of a subset of membrane protein cargo through the medial Golgi.

    PubMed

    Cox, John V; Kansal, Rita; Whitt, Michael A

    2016-06-01

    To evaluate the role of cytoplasmic domains of membrane-spanning proteins in directing trafficking through the secretory pathway, we generated fluorescently tagged VSV G tsO45 with either the native G tail (G) or a cytoplasmic tail derived from the chicken AE1-4 anion exchanger (G(AE)). We previously showed that these two proteins progressed through the Golgi with distinct kinetics. To investigate the basis for the differential sorting of G and G(AE), we analyzed the role of several Golgi-associated small GTP-binding proteins and found that Rab43 differentially regulated their transport through the Golgi. We show that the expression of GFP-Rab43 arrested the anterograde transport of G(AE) in a Rab43-positive medial Golgi compartment. GFP-Rab43 expression also inhibited the acquisition of endoH-resistant sugars and the surface delivery of G(AE), as well as the surface delivery of the AE1-4 anion exchanger. In contrast, GFP-Rab43 expression did not affect the glycosylation or surface delivery of G. Unexpectedly, down-regulation of endogenous Rab43 using small interfering RNA resulted in an increase in the accumulation of G(AE) on the cell surface while having minimal effect on the surface levels of G. Our data demonstrate that Rab43 regulates the sorting of a subset of membrane-spanning cargo as they progress through the medial Golgi. PMID:27053659

  14. Different involvement of subregions within dorsal premotor and medial frontal cortex for pro- and antisaccades.

    PubMed

    Cieslik, Edna C; Seidler, Isabelle; Laird, Angela R; Fox, Peter T; Eickhoff, Simon B

    2016-09-01

    The antisaccade task has been widely used to investigate cognitive action control. While the general network for saccadic eye movements is well defined, the exact location of eye fields within the frontal cortex strongly varies between studies. It is unknown whether this inconsistency reflects spatial uncertainty or is the result of different involvement of subregions for specific aspects of eye movement control. The aim of the present study was to examine functional differentiations within the frontal cortex by integrating results from neuroimaging studies analyzing pro- and antisaccade behavior using meta-analyses. The results provide evidence for a differential functional specialization of neighboring oculomotor frontal regions, with lateral frontal eye fields (FEF) and supplementary eye field (SEF) more often involved in prosaccades while medial FEF and anterior midcingulate cortex (aMCC) revealed consistent stronger involvement for antisaccades. This dissociation was furthermore mirrored by functional connectivity analyses showing that the lateral FEF and SEF are embedded in a motor output network, while medial FEF and aMCC are integrated in a multiple demand network. PMID:27211526

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  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. 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

  6. 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

  7. 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

  8. 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

  9. Culture of equine fibroblast-like synoviocytes on synthetic tissue scaffolds towards meniscal tissue engineering: a preliminary cell-seeding study

    PubMed Central

    Fox, Derek B.; Stoker, Aaron M.; Beatty, Mark; Cockrell, Mary; Janicek, John C.; Cook, James L.

    2014-01-01

    Introduction. Tissue engineering is a new methodology for addressing meniscal injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage formation, however, favorable in vitro culture conditions for synovium must be established in order to achieve this goal. The objective of this study was to determine cellularity, cell distribution, and extracellular matrix (ECM) formation of equine fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application in synovium-based meniscal tissue engineering. Scaffolds included open-cell poly-L-lactic acid (OPLA) sponges and polyglycolic acid (PGA) scaffolds cultured in static and dynamic culture conditions, and PGA scaffolds coated in poly-L-lactic (PLLA) in dynamic culture conditions. Materials and Methods. Equine FLS were seeded on OPLA and PGA scaffolds, and cultured in a static environment or in a rotating bioreactor for 12 days. Equine FLS were also seeded on PGA scaffolds coated in 2% or 4% PLLA and cultured in a rotating bioreactor for 14 and 21 days. Three scaffolds from each group were fixed, sectioned and stained with Masson’s Trichrome, Safranin-O, and Hematoxylin and Eosin, and cell numbers and distribution were analyzed using computer image analysis. Three PGA and OPLA scaffolds from each culture condition were also analyzed for extracellular matrix (ECM) production via dimethylmethylene blue (sulfated glycosaminoglycan) assay and hydroxyproline (collagen) assay. PLLA coated PGA scaffolds were analyzed using double stranded DNA quantification as areflection of cellularity and confocal laser microscopy in a fluorescent cell viability assay. Results. The highest cellularity occurred in PGA constructs cultured in a rotating bioreactor, which also had a mean sulfated glycosaminoglycan content of 22.3 µg per scaffold. PGA constructs cultured in static conditions had the lowest cellularity. Cells had difficulty adhering to OPLA and the PLLA coating of PGA

  10. 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

  11. 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

  12. 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

  13. Effectiveness and biocompatibility of a novel biological adhesive application for repair of meniscal tear on the avascular zone

    NASA Astrophysics Data System (ADS)

    Inoue, Takahito; Taguchi, Tetsushi; Imade, Shinji; Kumahashi, Nobuyuki; Uchio, Yuji

    2012-12-01

    We have investigated the effectiveness and safety of a newly developed biological adhesive for repair of meniscal tear. The adhesive was composed of disuccinimidyl tartrate (DST) as a crosslinker and human serum albumin (HSA) as a hardener. To determine adequate concentration, bonding strength was measured using a tensiometer 5 min after applying the adhesive on the avascular zone tear of porcine meniscus; it was compared with the strengths of commercially available cyanoacrylate-based and fibrin-based adhesives. In vivo examination was performed using Japanese white rabbits, creating longitudinal tears on the avascular zone of meniscus and applying DST-HSA adhesive. Three months after operation the rabbits were sacrificed and tension test and histological evaluation were performed. Bonding strength was measured in three porcine meniscus groups: (i) only suturing, (ii) suturing after applying the adhesive on surface and (iii) suturing using an adhesive-soaked suture. The optimum concentrations were 0.1 mmol of DST and 42 w/v% of HAS. Bonding strength was greatest with cyanoacrylate-based adhesive, followed by DST-HSA adhesive, and fibrin-based adhesive. No inflammation was observed in the synovium or surrounding tissues 3 months after using the DST-HSA adhesive. Bonding strength was greatest with DST-HSA adhesive-soaked suturing group (77 ± 6 N), followed by suturing only group (61 ± 5 N) and surface adhesive application group (60 ± 8 N). The newly developed DST-HSA adhesive is considered safe and may be effective in enforcement of bonding of avascular zone tear of the meniscus.

  14. Effects of Platelet-Rich Plasma Composition on Anabolic and Catabolic Activities in Equine Cartilage and Meniscal Explants

    PubMed Central

    McIlwraith, C. Wayne; Rodkey, William G.; Frisbie, David D.; Steadman, J.Richard

    2012-01-01

    Objective: To evaluate the effects of single- and double-spin preparations of platelet-rich plasma (PRP) on anabolic and catabolic activities of cartilage and meniscal explants in vitro. Methods: Single- and double-spin PRP was prepared using laboratory processing or commercial kits. The cellular contents were quantified, and each PRP was mixed in equal quantities with cell culture medium and added to cartilage or meniscus explant cultures, with or without interleukin 1 β (IL-1β). Extracellular matrix synthesis was quantified over 24 hours via 35S-sulfate and 3H-proline incorporation, while gene expression of catabolic enzymes was evaluated using real-time PCR. Results: The platelet concentration in single-spin laboratory PRP was 59% higher than blood. Platelet and white blood cell concentrations in single-spin laboratory and kit PRP were not significantly different, while the double-spin kit resulted in approximately 2.5-fold higher platelet and approximately 400-fold higher white blood cell concentrations. In cartilage cultures without IL-1β, radiolabel incorporation in single-spin PRP cultures was significantly higher than in double-spin cultures. Similar results were obtained for 35S-sulfate incorporation in meniscus cultures without IL-1β. In IL-1β, radiolabel incorporation was largely similar among all PRPs. After 24 hours of culture, ADAMTS-4 gene expression in cartilage was lowest for single-spin PRP, while expression in the double-spin kit was not significantly different from double-spin laboratory PRP in which platelets were concentrated 6-fold. Conclusions This study suggests that single-spin PRP preparations may be the most advantageous for intra-articular applications and that double-spin systems should be considered with caution. PMID:26069637

  15. 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

  16. 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

  17. 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.

  18. 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…

  19. 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

  20. 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…

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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…

  6. 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…

  7. 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

  8. 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

  9. 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

  10. Behavior-dependent short-term assembly dynamics in the medial prefrontal cortex.

    PubMed

    Fujisawa, Shigeyoshi; Amarasingham, Asohan; Harrison, Matthew T; Buzsáki, György

    2008-07-01

    Although short-term plasticity is believed to play a fundamental role in cortical computation, empirical evidence bearing on its role during behavior is scarce. Here we looked for the signature of short-term plasticity in the fine-timescale spiking relationships of a simultaneously recorded population of physiologically identified pyramidal cells and interneurons, in the medial prefrontal cortex of the rat, in a working memory task. On broader timescales, sequentially organized and transiently active neurons reliably differentiated between different trajectories of the rat in the maze. On finer timescales, putative monosynaptic interactions reflected short-term plasticity in their dynamic and predictable modulation across various aspects of the task, beyond a statistical accounting for the effect of the neurons' co-varying firing rates. Seeking potential mechanisms for such effects, we found evidence for both firing pattern-dependent facilitation and depression, as well as for a supralinear effect of presynaptic coincidence on the firing of postsynaptic targets. PMID:18516033

  11. Use of foot orthoses and calf stretching for individuals with medial tibial stress syndrome.

    PubMed

    Loudon, Janice K; Dolphino, Martin R

    2010-02-01

    Use of orthotics and calf stretching may alleviate symptoms in runners with medial tibial stress syndrome (MTSS). The objective of this study was to determine which patients with MTSS have a positive response to off-the-shelf foot orthoses and calf stretching based on selected clinical tests to establish a clinical prediction rule. This prospective cohort/predictive validity study enrolled 23 women and men aged 22 to 44 years with symptoms of MTSS. Interventions included off-the-shelf basic foot orthotics and calf stretching. Fifteen of the 23 runners had a 50% reduction of pain in 3 weeks of intervention. Duration was a significant factor that differentiated groups. Although an initial treatment for runners with MTSS may include off-the-shelf orthotics and calf stretching, this regimen should be only one component of an individualized rehabilitation program. PMID:20400435

  12. Defining the Value of Future Research to Identify the Preferred Treatment of Meniscal Tear in the Presence of Knee Osteoarthritis

    PubMed Central

    Losina, Elena; Dervan, Elizabeth E.; Paltiel, A. David; Dong, Yan; Wright, R. John; Spindler, Kurt P.; Mandl, Lisa A.; Jones, Morgan H.; Marx, Robert G.; Safran-Norton, Clare E.; Katz, Jeffrey N.

    2015-01-01

    Background Arthroscopic partial meniscectomy (APM) is extensively used to relieve pain in patients with symptomatic meniscal tear (MT) and knee osteoarthritis (OA). Recent studies have failed to show the superiority of APM compared to other treatments. We aim to examine whether existing evidence is sufficient to reject use of APM as a cost-effective treatment for MT+OA. Methods We built a patient-level microsimulation using Monte Carlo methods and evaluated three strategies: Physical therapy (‘PT’) alone; PT followed by APM if subjects continued to experience pain (‘Delayed APM’); and ‘Immediate APM’. Our subject population was US adults with symptomatic MT and knee OA over a 10 year time horizon. We assessed treatment outcomes using societal costs, quality-adjusted life years (QALYs), and calculated incremental cost-effectiveness ratios (ICERs), incorporating productivity costs as a sensitivity analysis. We also conducted a value-of-information analysis using probabilistic sensitivity analyses. Results Calculated ICERs were estimated to be $12,900/QALY for Delayed APM as compared to PT and $103,200/QALY for Immediate APM as compared to Delayed APM. In sensitivity analyses, inclusion of time costs made Delayed APM cost-saving as compared to PT. Improving efficacy of Delayed APM led to higher incremental costs and lower incremental effectiveness of Immediate APM in comparison to Delayed APM. Probabilistic sensitivity analyses indicated that PT had 3.0% probability of being cost-effective at a willingness-to-pay (WTP) threshold of $50,000/QALY. Delayed APM was cost effective 57.7% of the time at WTP = $50,000/QALY and 50.2% at WTP = $100,000/QALY. The probability of Immediate APM being cost-effective did not exceed 50% unless WTP exceeded $103,000/QALY. Conclusions We conclude that current cost-effectiveness evidence does not support unqualified rejection of either Immediate or Delayed APM for the treatment of MT+OA. The amount to which society would be

  13. 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…

  14. 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…

  15. MTA index: a simple 2D-method for assessing atrophy of the medial temporal lobe using clinically available neuroimaging

    PubMed Central

    Menéndez-González, Manuel; López-Muñiz, Alfonso; Vega, José A.; Salas-Pacheco, José M.; Arias-Carrión, Oscar

    2014-01-01

    Background and purpose: Despite a strong correlation to severity of AD pathology, the measurement of medial temporal lobe atrophy (MTA) is not being widely used in daily clinical practice as a criterion in the diagnosis of prodromal and probable AD. This is mainly because the methods available to date are sophisticated and difficult to implement for routine use in most hospitals—volumetric methods—or lack objectivity—visual rating scales. In this pilot study we aim to describe a new, simple and objective method for measuring the rate of MTA in relation to the global atrophy using clinically available neuroimaging and describe the rationale behind this method. Description: This method consists of calculating a ratio with the area of 3 regions traced manually on one single coronal MRI slide at the level of the interpeduncular fossa: (1) the medial temporal lobe (MTL) region (A); (2) the parenchima within the medial temporal region, that includes the hippocampus and the parahippocampal gyrus—the fimbria taenia and plexus choroideus are excluded—(B); and (3) the body of the ipsilateral lateral ventricle (C). Therefrom we can compute the ratio “Medial Temporal Atrophy index” at both sides as follows: MTAi = (A − B)× 10/C. Conclusions: The MTAi is a simple 2D-method for measuring the relative extent of atrophy in the MTL in relation to the global brain atrophy. This method can be useful for a more accurate diagnosis of AD in routine clinical practice. Further studies are needed to assess the usefulness of MTAi in the diagnosis of early AD, in tracking the progression of AD and in the differential diagnosis of AD with other dementias. PMID:24715861

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

    Background: Few studies have evaluated the effect of existing articular cartilage damage and sex on joint space measurements after isolated degenerative medial meniscus tears. Purpose: To determine what factors affected joint space width and narrowing in patients after removal of isolated degenerative medial meniscus tears. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 62 patients (15 women and 47 men) with all ligaments intact, no previous surgery to either knee, and an isolated degenerative medial meniscus tear removed in 1 knee were examined. The mean age at examination was 58.2 years at a mean follow-up of 9.4 years (range, 4-20 years). Subjective results were obtained with the International Knee Documentation Committee (IKDC) knee survey. Radiographs were taken using 45° weightbearing posteroanterior views. Midpoint and perceived minimum joint space width of the medial and lateral compartments of both knees were measured to the nearest 0.1 mm by 2 observers at different times, and they were blinded as to the previous measurements (Pearson intra- and interclass correlations, >0.93). Joint space narrowing was found by calculating the difference in joint space width between knees. Percentage of normal joint space loss was calculated by dividing joint space narrowing by the joint space width in the contralateral knee. Other factors considered were patient sex and Outerbridge grading of articular cartilage. Results: Women had a mean 1.5 mm less normal joint space width than men in the involved and noninvolved knees (P < .01). Mean joint space narrowing was 0.7 mm for both measurements. The mean ± standard deviation narrowing was 0.4 ± 1.2 mm for patients with grade 0-2 damage and 1.1 ± 1.3 for patients with grade 3-4 damage (P = .04). Five women (33%) and 3 men (6%) had narrowing of >50% of the normal joint space as measured in the noninjured knee (P = .016). The mean IKDC total score was 66.1 points for women, which was statistically

  9. 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

  10. Meniscal allograft transplantation

    MedlinePlus

    ... the outside (lateral meniscus). When a meniscus is torn, it is commonly removed by knee arthroscopy . Some ... or nearly all of the meniscus cartilage is torn or has to be removed. The new meniscus ...

  11. Meniscal tears (image)

    MedlinePlus

    ... the shock-absorbing cartilage in the knee. The meniscus is a C-shaped fibrous cartilage that is ... joints forming a buffer between the bones. The meniscus also serves as a shock-absorption system, assists ...

  12. Meniscal allograft transplantation

    MedlinePlus

    Meniscus transplant; Surgery - knee - meniscus transplant; Surgery - knee - cartilage; Arthroscopy - knee - meniscus transplant ... you are a good candidate for a meniscus transplant, x-rays of your knee are usually taken ...

  13. Brachial branches of the medial antebrachial cutaneous nerve: A case report with its clinical significance and a short review of the literature.

    PubMed

    Stylianos, Kapetanakis; Konstantinos, Giatroudakis; Pavlos, Pavlidis; Aliki, Fiska

    2016-01-01

    The medial antebrachial cutaneous nerve (MACN) is a branch of the brachial plexus with a great variation within its branches. Knowledge of these variations is critical to neurologists, hand surgeons, plastic surgeons, and vascular surgeons. The aim of this study was to search for variations of the MACN and to discuss their clinical significance. For this study, six arm cadavers from three fresh cadavers were dissected and examined to find and study possible anatomical variations of the MACN. The authors report a rare case of a variation of the MACN, in which there are four brachial cutaneous branches, before the separation to anterior (volar) and posterior (ulnar) branch, that provide sensory innervation to the medial, inferior half of the arm, in the area that is commonly innervated from the medial brachial cutaneous nerve. To our knowledge, this is the first documented case of this nerve variation. This variation should be taken into serious consideration for the differential diagnosis of patients with complaints of hypoesthesia, pain, and paresthesia and for the surgical operations in the medial part of the arm. PMID:27365965

  14. Brachial branches of the medial antebrachial cutaneous nerve: A case report with its clinical significance and a short review of the literature

    PubMed Central

    Stylianos, Kapetanakis; Konstantinos, Giatroudakis; Pavlos, Pavlidis; Aliki, Fiska

    2016-01-01

    The medial antebrachial cutaneous nerve (MACN) is a branch of the brachial plexus with a great variation within its branches. Knowledge of these variations is critical to neurologists, hand surgeons, plastic surgeons, and vascular surgeons. The aim of this study was to search for variations of the MACN and to discuss their clinical significance. For this study, six arm cadavers from three fresh cadavers were dissected and examined to find and study possible anatomical variations of the MACN. The authors report a rare case of a variation of the MACN, in which there are four brachial cutaneous branches, before the separation to anterior (volar) and posterior (ulnar) branch, that provide sensory innervation to the medial, inferior half of the arm, in the area that is commonly innervated from the medial brachial cutaneous nerve. To our knowledge, this is the first documented case of this nerve variation. This variation should be taken into serious consideration for the differential diagnosis of patients with complaints of hypoesthesia, pain, and paresthesia and for the surgical operations in the medial part of the arm. PMID:27365965

  15. Developmental and comparative aspects of posterior medial thalamocortical innervation of barrel cortex in mice and rats

    PubMed Central

    Kichula, Elizabeth A.; Huntley, George W.

    2016-01-01

    The thalamocortical projection to rodent barrel cortex consists of inputs from the ventral posterior medial (VPM) and posterior medial (POm) nuclei that terminate in largely non-overlapping territories in and outside of layer IV. This projection in both rats and mice has been used extensively to study development and plasticity of highly-organized synaptic circuits. Whereas the VPM pathway has been well characterized in both rats and mice, organization of the POm pathway has only been described in rats, and no studies have focused exclusively on the development of the POm projection. Here, using transport of PHA-L or carbocyanine dyes, we characterize the POm thalamocortical innervation of adult mouse barrel cortex and describe its early postnatal development in both mice and rats. In adult mice, POm inputs form a dense plexus in layer Va that extends uniformly underneath layer IV barrels and septa. Innervation of layer IV is very sparse; a clear septal innervation pattern is evident only at the layer IV/Va border. This pattern differs subtly from that described previously in rats. Developmentally, in both species, POm axons are present in barrel cortex at birth, where in mice, they occupy layer IV as it differentiates. In contrast, in rats, POm axons do not enter layer IV until 1–2 days after its emergence from the cortical plate. In both species, arbors undergo progressive and directed growth. However, no layer IV septal innervation pattern emerges until several days after the cytoarchitectonic appearance of barrels and well after the emergence of whisker-related clusters of VPM thalamocortical axons. The mature pattern resolves earlier in rats than in mice. Taken together, these data reveal anatomical differences between mice and rats in development and organization of POm inputs to barrel cortex, with implications for species differences in the nature and plasticity of lemniscal and paralemniscal information processing. PMID:18496871

  16. 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

  17. 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

  18. 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

  19. Whole genome expression profiling of the medial and lateral substantia nigra in Parkinson's disease.

    PubMed

    Moran, L B; Duke, D C; Deprez, M; Dexter, D T; Pearce, R K B; Graeber, M B

    2006-03-01

    We have used brain tissue from clinically well-documented and neuropathologically confirmed cases of sporadic Parkinson's disease to establish the transcriptomic expression profile of the medial and lateral substantia nigra. In addition, the superior frontal cortex was analyzed in a subset of the same cases. DNA oligonucleotide microarrays were employed, which provide whole human genome coverage. A total of 570 genes were found to be differentially regulated at a high level of significance. A large number of differentially regulated expressed sequence tags were also identified. Levels of mRNA sequences encoded by genes of key interest were validated by means of quantitative real-time polymerase chain reaction (PCR). Comparing three different normalization procedures, results based on the recently published GeneChip Robust Multi Array algorithm were found to be the most accurate predictor of real-time PCR results. Several new candidate genes which map to PARK loci are reported. In addition, the DNAJ family of chaperones is discussed in the context of Parkinson's disease pathogenesis. PMID:16344956

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. Osteoarthritis prevention and meniscus regeneration induced by transplantation of mesenchymal stem cell sheet in a rat meniscal defect model

    PubMed Central

    QI, YIYING; CHEN, GUANGNAN; FENG, GANG

    2016-01-01

    Transplantation of mesenchymal stem cells (MSCs) is a potential therapy for meniscus regeneration. However, when using single cell suspension injection, there is frequently a significant loss of cells, with only a small percentage of cells remaining at the target site. This issue may be solved with the use of MSC sheets. In the present study, we investigated whether the use of MSC sheets were able to regenerate the meniscus effectively in a rat meniscectomized model. The anterior half of the medial meniscus in 10 rats was excised and an MSC sheet was transplanted in the MSC sheet treatment group, while untreated rats served as the control. After 4 and 8 weeks, the knee joints were examined by gross and histological observation. Histological observation revealed that the anterior portion of meniscus was similar to the native tissue, showing typical fibrochondrocytes surrounded by richer extracellular matrix in the MSC sheet group. In addition, predominant collagen-rich matrix bridging the interface was observed and the neo-meniscus integrated well with its host meniscus. Furthermore, degenerative changes of tibial plateau and femoral condyle occurred in the two groups. MSC sheet transplantation alleviated the degenerative changes efficiently. In conclusion, transplantation of MSC sheets may efficiently promote meniscus regeneration, as well as inhibit the progression of osteoarthritis in knee joints. PMID:27347022

  16. 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

  17. 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

  18. Evaluation of age estimation in forensic medicine by examination of medial clavicular ossification from thin-slice computed tomography images.

    PubMed

    Gurses, Murat Serdar; Inanir, Nursel Turkmen; Gokalp, Gokhan; Fedakar, Recep; Tobcu, Eren; Ocakoglu, Gokhan

    2016-09-01

    Forensic age estimation, a recent topic of research in forensic medicine, is of primary importance to criminal and civil law. Previous studies indicate that the observation of medial clavicular ossification allows for age discrimination along the completed 18th and 21st years of life. Experts recommend that the Schmeling and Kellinghaus methods be used together. In this study, we used these staging methods to retrospectively analyze 725 case studies (385 males, 340 females) of thin-slice computed tomography (CT) images, ranging from 0.6 to 1 mm in thickness, from individuals aged 10 to 35 years. Stage 1 was found at 18 years of age maximum for males, whereas it was found at 17 years of age for females. Stage 2a was found at 18 years of age maximum for both genders. Stage 3c was initially observed at 18 years for both genders. Stage 4 was initially found at 21 years for males and 20 years for females. Stage 5 was initially observed at 25 years for both genders. Of note, stage 3c was found close to 19 years of age for both genders (18.92 years for male, 18.99 years for female), and it may be employed to differentiate along the age majority cutoff. The data obtained from our study were consistent with previous studies. We believe that such a comprehensive database will greatly contribute to future studies focusing on medial clavicular ossification based on thin-slice CT. Moreover, we also recommend that if medial clavicular ossification based on CT is to be examined for forensic age estimation, both methods should be employed together. PMID:27352083

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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…

  13. 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

  14. [Non-dislocated osteoporotic insufficiency fracture of the medial femoral neck. SPECT/CT makes the diagnostic difference].

    PubMed

    Rieger, B; Friederich, N F; Rasch, H; Hirschmann, M T

    2014-04-01

    Osteoporotic fragility fractures of the femoral neck are the most common type of fractures in the elderly and are associated with a high mortality. Most frequently these fractures are due to falls but spontaneous onset has also been described. In these patients the insufficient quantity and quality of the osteoporotic bone finally leads to the development of a fragility or insufficiency fracture. In some cases of nondisplaced insufficiency fractures the diagnosis cannot be established by conventional radiographs alone and magnetic resonance imaging (MRI), single proton emission computed tomography (SPECT) or SPECT/CT are considered as diagnostic adjuncts. We report the case of an 83-year-old patient who had complained of ongoing weight-bearing pelvic pain for over 6 months. There was no history of trauma. The clinical conventional radiographs as well as CT could not elucidate the cause of the problems. To differentiate between lumbal and hip pain a SPECT/CT was performed and the diagnosis of a medial femoral neck insufficiency fracture was established. In the delayed phase a band-like increased tracer uptake within the medial femoral neck was observed. The SPECT/CT procedure is a promising diagnostic alternative for geriatric patients and can be particularly recommended in cases of persistent unclear pelvic or lumbar spine pain in the elderly. PMID:23949134

  15. 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

  16. 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

  17. The development of performance-monitoring function in the posterior medial frontal cortex

    PubMed Central

    Fitzgerald, Kate Dimond; Perkins, Suzanne C.; Angstadt, Mike; Johnson, Timothy; Stern, Emily R.; Welsh, Robert C.; Taylor, Stephan F.

    2009-01-01

    Background Despite its critical role in performance-monitoring, the development of posterior medial prefrontal cortex (pMFC) in goal-directed behaviors remains poorly understood. Performance monitoring depends on distinct, but related functions that may differentially activate the pMFC, such as monitoring response conflict and detecting errors. Developmental differences in conflict- and error-related activations, coupled with age-related changes in behavioral performance, may confound attempts to map the maturation of pMFC functions. To characterize the development of pMFC-based performance monitoring functions, we segregated interference and error-processing, while statistically controlling for performance. Methods Twenty-one adults and 23 youth performed an event-related version of the Multi-Source Interference Task during functional magnetic resonance imaging (fMRI). Linear modeling of interference and error contrast estimates derived from the pMFC were regressed on age, while covarying for performance. Results Interference- and error-processing were associated with robust activation of the pMFC in both youth and adults. Among youth, interference- and error-related activation of the pMFC increased with age, independent of performance. Greater accuracy associated with greater pMFC activity during error commission in both groups. Discussion Increasing pMFC response to interference and errors occurs with age, likely contributing to the improvement of performance monitoring capacity during development. PMID:19913101

  18. Social predisposition dependent neuronal activity in the intermediate medial mesopallium of domestic chicks (Gallus gallus domesticus).

    PubMed

    Mayer, Uwe; Rosa-Salva, Orsola; Lorenzi, Elena; Vallortigara, Giorgio

    2016-09-01

    Species from phylogenetically distant animal groups, such as birds and primates including humans, share early experience-independent social predispositions that cause offspring, soon after birth, to attend to and learn about conspecifics. One example of this phenomenon is provided by the behaviour of newly-hatched visually-naïve domestic chicks that preferentially approach a stimulus resembling a conspecific (a stuffed fowl) rather than a less naturalistic object (a scrambled version of the stuffed fowl). However, the neuronal mechanisms underlying this behaviour are mostly unknown. Here we analysed chicks' brain activity with immunohistochemical detection of the transcription factor c-Fos. In a spontaneous choice test we confirmed a significant preference for approaching the stuffed fowl over a texture fowl (a fowl that was cut in small pieces attached to the sides of a box in scrambled order). Comparison of brain activation of a subgroup of chicks that approached either one or the other stimulus revealed differential activation in an area relevant for imprinting (IMM, intermediate medial mesopallium), suggesting that a different level of plasticity is associated with approach to naturalistic and artificial stimuli. c-Fos immunoreactive neurons were present also in the intermediate layers of the optic tectum (a plausible candidate for processing early social predispositions) showing a trend similar to the results for the IMM. PMID:27173429

  19. Viral-mediated Labeling and Transplantation of Medial Ganglionic Eminence (MGE) Cells for In Vivo Studies

    PubMed Central

    Vogt, Daniel; Wu, Pei-Rung; Sorrells, Shawn F.; Arnold, Christine; Alvarez-Buylla, Arturo; Rubenstein, John L. R.

    2015-01-01

    GABAergic cortical interneurons, derived from the embryonic medial and caudal ganglionic eminences (MGE and CGE), are functionally and morphologically diverse. Inroads have been made in understanding the roles of distinct cortical interneuron subgroups, however, there are still many mechanisms to be worked out that may contribute to the development and maturation of different types of GABAergic cells. Moreover, altered GABAergic signaling may contribute to phenotypes of autism, schizophrenia and epilepsy. Specific Cre-driver lines have begun to parcel out the functions of unique interneuron subgroups. Despite the advances in mouse models, it is often difficult to efficiently study GABAergic cortical interneuron progenitors with molecular approaches in vivo. One important technique used to study the cell autonomous programming of these cells is transplantation of MGE cells into host cortices. These transplanted cells migrate extensively, differentiate, and functionally integrate. In addition, MGE cells can be efficiently transduced with lentivirus immediately prior to transplantation, allowing for a multitude of molecular approaches. Here we detail a protocol to efficiently transduce MGE cells before transplantation for in vivo analysis, using available Cre-driver lines and Cre-dependent expression vectors. This approach is advantageous because it combines precise genetic manipulation with the ability of these cells to disperse after transplantation, permitting greater cell-type specific resolution in vivo. PMID:25938985

  20. Valence-based age differences in medial prefrontal activity during impression formation.

    PubMed

    Cassidy, Brittany S; Leshikar, Eric D; Shih, Joanne Y; Aizenman, Avigael; Gutchess, Angela H

    2013-01-01

    Reports of age-related changes to medial prefrontal cortex (mPFC) activity during socio-cognitive tasks have shown both age-equivalence and under recruitment. Emotion work illustrates selective mPFC response dependent on valence, such that negative emotional images evoke increased ventral mPFC activity for younger adults, while older adults recruit vmPFC more for positive material. By testing whether this differential age-related response toward valenced material is also present for the social task of forming impressions, we may begin to understand inconsistencies regarding when age differences are present vs. absent in the literature. Using fMRI, participants intentionally formed impressions of positive and negative face-behavior pairs in anticipation of a memory task. Extending previous findings to a social task, valence-based reversals were present in dorsal and ventral mPFC, and posterior cingulate cortex. Younger adults elicited increased activity when forming negative impressions, while older adults had more recruitment when forming positive impressions. This suggests an age-related shift toward emphasizing positive social information may be reflected in the recruitment of regions supporting forming impressions. Overall, the results indicate an age-related shift in neural response to socio-cognitive stimuli that is valence dependent rather than a general age-related reduction in activity, in part informing prior inconsistencies within the literature. PMID:23998453

  1. Adaptation to cognitive context and item information in the medial temporal lobes

    PubMed Central

    Diana, Rachel A.; Yonelinas, Andrew P.; Ranganath, Charan

    2012-01-01

    The medial temporal lobes (MTL) play an essential role in episodic memory, and accumulating evidence indicates that two MTL subregions—the perirhinal (PRc) and parahippocampal (PHc) cortices—might have different functions. According to the binding of item and context theory (Eichenbaum et al., 2007; Diana et al., 2007), PRc is involved in processing item information, the target of memory encoding, whereas PHc is involved in processing context information, peripheral information that identifies the circumstances of the episode. Here, we used functional magnetic resonance imaging (fMRI) adaptation to test the roles of different MTL subregions in the processing of item and context information. Participants were scanned while viewing a series of objects. Each object was presented with a unique semantic encoding question that elicited a salient cognitive context. The object picture, the encoding question, both, or neither were immediately repeated. We found that PRc activity was sensitive to repetition of the object but not the encoding question whereas PHc activity was sensitive to repetition of the encoding question but not the object. These data are consistent with the idea that the PRc and PHc are differentially involved in the representation of item and context information and additionally suggest that the role of the PHc extends to nonspatial, cognitive context information. PMID:22846335

  2. Chronic stress-like syndrome as a consequence of medial site subthalamic stimulation in Parkinson's disease.

    PubMed

    Růžička, Filip; Jech, Robert; Nováková, Lucie; Urgošík, Dušan; Bezdíček, Ondřej; Vymazal, Josef; Růžička, Evžen

    2015-02-01

    Considering the functional organization of the subthalamic nucleus (STN), we hypothesized that subthalamic deep brain stimulation (STN-DBS) in Parkinson's disease might have a differential impact on the hypothalamic-pituitary-adrenal axis in relation to the position of active stimulating contact within the STN. In addition, we searched for any STN-DBS-related morning plasma cortisol changes in association with postoperative anxiety and weight gain. A plasma cortisol measurement was performed on the day of initiation of bilateral STN-DBS and repeated after 1 and 17 months in twenty patients with advanced Parkinson's disease. The body weight change and anxiety scores following the implantation were assessed as well. The electrode positions in the STN were determined on T1-weighted magnetic resonance images. After initiation of stimulation, cortisol levels significantly decreased and the cortisol changes after 1 and 17 months strongly correlated with the position of active contact in the subthalamic area. Patients with at least one contact located more medially in the STN experienced a significantly greater decrease of cortisol than those with one or both active contacts more laterally. Furthermore, the lower cortisol levels were strongly associated with higher trait anxiety and weight gain. These changes mimicked the effects of chronic stress and suggest the disturbing impact of STN-DBS on limbic and motivational systems. PMID:25554999

  3. Optochemical dissection of T-box gene-dependent medial floor plate development

    PubMed Central

    Payumo, Alexander Y.; Walker, Whitney J.; McQuade, Lindsey E.; Yamazoe, Sayumi; Chen, James K.

    2015-01-01

    In addition to their cell-autonomous roles in mesoderm development, the zebrafish T-box transcription factors no tail a (ntla) and spadetail (spt/tbx16) are required for medial floor plate (MFP) formation. Posterior MFP cells are completely absent in zebrafish embryos lacking both Ntla and Spt function, and genetic mosaic analyses have shown that the two T-box genes promote MFP development in a non-cell-autonomous manner. Based on these observations, it has been proposed that Ntla/Spt-dependent mesoderm-derived signals are required for the induction of posterior but not anterior MFP cells. To investigate the mechanisms by which Ntla and Spt regulate MFP development, we have used photoactivatable caged morpholinos (cMOs) to silence these T-box genes with spatiotemporal control. We find that posterior MFP formation requires Ntla or Spt activity during early gastrulation, specifically in lateral margin-derived cells that converge toward the midline during epiboly and somitogenesis. Nodal signaling-dependent MFP specification is maintained in the absence of Ntla and Spt function; however midline cells in ntla;spt morphants exhibit aberrant morphogenetic movements, resulting in their anterior mislocalization. Our findings indicate that Ntla and Spt do not differentially regulate MFP induction along the anterior-posterior axis; rather, the T-box genes act redundantly within margin-derived cells to promote the posterior extension of MFP progenitors. PMID:25781211

  4. 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

  5. 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

  6. Humeral Head Arthroplasty and Meniscal Allograft Resurfacing of the Glenoid: A Concise Follow-up of a Previous Report and Survivorship Analysis.

    PubMed

    Bois, Aaron J; Whitney, Ian J; Somerson, Jeremy S; Wirth, Michael A

    2015-10-01

    The two to five-year results of humeral head arthroplasty and lateral meniscal allograft resurfacing of the glenoid in patients fifty-five years of age or younger were previously reported by the senior author (M.A.W.). The purpose of the present study was to report the survival rate, clinical findings, and radiographic results of the original thirty shoulders (thirty patients) followed for a mean duration of 8.3 years (range, five to twelve years). The scores on the visual analog scale for pain, American Shoulder and Elbow Surgeons scoring system, and Simple Shoulder Test were significantly improved at the latest follow-up evaluation compared with the preoperative findings (p < 0.001). Radiographic indices of posterior subluxation did not significantly increase from the immediate postoperative imaging to the latest radiographs, while the glenohumeral joint space demonstrated a gradual decrease. Nine (30%) of thirty shoulders were known to have undergone a reoperation. The present study demonstrated that biological glenoid resurfacing combined with hemiarthroplasty can provide significant improvement in shoulder function and pain relief in young patients with glenohumeral arthritis; however, mid-term follow-up at a mean of over eight years demonstrated a high reoperation rate. PMID:26446964

  7. Nicotine Dependence Reveals Distinct Responses from Neurons and Their Resident Nicotinic Receptors in Medial Habenula.

    PubMed

    Shih, Pei-Yu; McIntosh, J Michael; Drenan, Ryan M

    2015-12-01

    Nicotinic acetylcholine receptors (nAChRs) are the molecular target of nicotine. nAChRs in the medial habenula (MHb) have recently been shown to play a role in nicotine dependence, but it is not clear which nAChR subtypes or MHb neuron types are most important. To identify MHb nAChRs and/or cell types that play a role in nicotine dependence, we studied these receptors and cells with brain slice electrophysiology using both acute and chronic nicotine application. Cells in the ventroinferior (MHbVI) and ventrolateral MHb (MHbVL) subregions expressed functional nAChRs with different pharmacology. Further, application of nicotine to cells in these subregions led to different action potential firing patterns. The latter result was correlated with a differing ability of nicotine to induce nAChR desensitization. Chronic nicotine caused functional upregulation of nAChRs selectively in MHbVI cells, but did not change nAChR function in MHbVL. Importantly, firing responses were also differentially altered in these subregions following chronic nicotine. MHbVI neurons treated chronically with nicotine exhibited enhanced basal pacemaker firing but a blunted nicotine-induced firing response. MHbVL neurons did not change their firing properties in response to chronic nicotine. Together, these results suggest that acute and chronic nicotine differentially affect nAChR function and output of cells in MHb subregions. Because the MHb extensively innervates the interpeduncular nucleus, an area critical for both affective and somatic signs of withdrawal, these results could reflect some of the neurophysiological changes thought to occur in the MHb to the interpeduncular nucleus circuit in human smokers. PMID:26429939

  8. Hypoactive medial prefrontal cortex functioning in adults reporting childhood emotional maltreatment.

    PubMed

    van Harmelen, Anne-Laura; van Tol, Marie-José; Dalgleish, Tim; van der Wee, Nic J A; Veltman, Dick J; Aleman, André; Spinhoven, Philip; Penninx, Brenda W J H; Elzinga, Bernet M

    2014-12-01

    Childhood emotional maltreatment (CEM) has adverse effects on medial prefrontal cortex (mPFC) morphology, a structure that is crucial for cognitive functioning and (emotional) memory and which modulates the limbic system. In addition, CEM has been linked to amygdala hyperactivity during emotional face processing. However, no study has yet investigated the functional neural correlates of neutral and emotional memory in adults reporting CEM. Using functional magnetic resonance imaging, we investigated CEM-related differential activations in mPFC during the encoding and recognition of positive, negative and neutral words. The sample (N = 194) consisted of patients with depression and/or anxiety disorders and healthy controls (HC) reporting CEM (n = 96) and patients and HC reporting no abuse (n = 98). We found a consistent pattern of mPFC hypoactivation during encoding and recognition of positive, negative and neutral words in individuals reporting CEM. These results were not explained by psychopathology or severity of depression or anxiety symptoms, or by gender, level of neuroticism, parental psychopathology, negative life events, antidepressant use or decreased mPFC volume in the CEM group. These findings indicate mPFC hypoactivity in individuals reporting CEM during emotional and neutral memory encoding and recognition. Our findings suggest that CEM may increase individuals' risk to the development of psychopathology on differential levels of processing in the brain; blunted mPFC activation during higher order processing and enhanced amygdala activation during automatic/lower order emotion processing. These findings are vital in understanding the long-term consequences of CEM. PMID:24493840

  9. Visuo-spatial memory deficits following medial temporal lobe damage: A comparison of three patient groups.

    PubMed

    Esfahani-Bayerl, Nazli; Finke, Carsten; Braun, Mischa; Düzel, Emrah; Heekeren, Hauke R; Holtkamp, Martin; Hasper, Dietrich; Storm, Christian; Ploner, Christoph J

    2016-01-29

    The contributions of the hippocampal formation and adjacent regions of the medial temporal lobe (MTL) to memory are still a matter of debate. It is currently unclear, to what extent discrepancies between previous human lesion studies may have been caused by the choice of distinct patient models of MTL dysfunction, as disorders affecting this region differ in selectivity, laterality and mechanisms of post-lesional compensation. Here, we investigated the performance of three distinct patient groups with lesions to the MTL with a battery of visuo-spatial short-term memory tasks. Thirty-one subjects with either unilateral damage to the MTL (postsurgical lesions following resection of a benign brain tumor, 6 right-sided lesions, 5 left) or bilateral damage (10 post-encephalitic lesions, 10 post-anoxic lesions) performed a series of tasks requiring short-term memory of colors, locations or color-location associations. We have shown previously that performance in the association task critically depends on hippocampal integrity. Patients with postsurgical damage of the MTL showed deficient performance in the association task, but performed normally in color and location tasks. Patients with left-sided lesions were almost as impaired as patients with right-sided lesions. Patients with bilateral post-encephalitic lesions showed comparable damage to MTL sub-regions and performed similarly to patients with postsurgical lesions in the association task. However, post-encephalitic patients showed additional impairments in the non-associative color and location tasks. A strikingly similar pattern of deficits was observed in post-anoxic patients. These results suggest a distinct cerebral organization of associative and non-associative short-term memory that was differentially affected in the three patient groups. Thus, while all patient groups may provide appropriate models of medial temporal lobe dysfunction in associative visuo-spatial short-term memory, additional deficits in

  10. Location and tension of the medial palpebral ligament.

    PubMed

    Hwang, Kun; Huan, Fan; Nam, Yong Seok; Han, Seung Ho; Kim, Dae Joong

    2013-11-01

    The aim of this study was to elucidate the precise anatomic location and tension of the medial palpebral ligament (MPL). Eleven hemifaces of 10 fresh Korean adult cadavers were used in this study. Nine specimens were used for measurement of dissection and tension, and 2 were used for histologic study. Measurements of tensile strength of each part of the MPL and Horner muscle were performed using a force gauge.The MPL consisted of 2 layers in all specimens dissected. The superficial layer of the palpebral ligament (SMPL) was observed from the anterior lacrimal crest to the upper and lower tarsal plates. The deep layer of the palpebral ligament (DMPL) lay from the anterior lacrimal crest to the posterior lacrimal crest, covering the lacrimal sac. The Horner muscle was observed at the posterior lacrimal crest just lateral to the attachment of the DMPL and ran laterally to the tarsal plate deep to the SMPL. The SMPL began at 4.5 ± 2.3 mm lateral to the nasomaxillary suture line to the upper and lower tarsal plates. Its transverse length was 9.6 ± 1.5 mm, and vertical width was 2.4 ± 0.7 mm, and its thickness was 4.5 ± 2.3 mm. The transverse length of the DMPL was 3.7 ± 0.4 mm, and its vertical width was 2.9 ± 1.3 mm, with a thickness of 0.3 ± 0.1 mm. The transverse length of the Horner muscle was 7.6 ± 1.9 mm, and its vertical width was 4.06 ± 1.5 mm, with a thickness of 0.4 ± 0.1 mm. The tensile strength of the SMPL was 13.4 ± 3.2 N, that of the DMPL was 4.1 ± 1.7 N, and that for Horner muscle was 9.0 ± 3.1 N. The tensile strength of the SMPL was significantly higher than that of the DMPL (P = 0.003).We reconfirmed that the MPL consisted of 2 layers: superficial layer and deep layer. Our results might be of use in surgeries of the medial canthi. PMID:24220420

  11. Manual Planimetry of the Medial Temporal Lobe Versus Automated Volumetry of the Hippocampus in the Diagnosis of Alzheimer's Disease

    PubMed Central

    Suárez-Sanmartin, Esther; García, Ciara; Martínez-Camblor, Pablo; Westman, Eric; Simmons, Andy

    2016-01-01

    Introduction: Though a disproportionate rate of atrophy in the medial temporal lobe (MTA) represents a reliable marker of Alzheimer’s disease (AD) pathology, measurement of the MTA is not currently widely used in daily clinical practice. This is mainly because the methods available to date are sophisticated and difficult to implement in clinical practice (volumetric methods), are poorly explored (linear and planimetric methods), or lack objectivity (visual rating). Here, we aimed to compare the results of a manual planimetric measure (the yearly rate of absolute atrophy of the medial temporal lobe, 2D-yrA-MTL) with the results of an automated volumetric measure (the yearly rate of atrophy of the hippocampus, 3D-yrA-H). Methods: A series of 1.5T MRI studies on 290 subjects in the age range of 65–85 years, including patients with AD (n = 100), mild cognitive impairment (MCI) (n = 100), and matched controls (n = 90) from the AddNeuroMed study, were examined by two independent subgroups of researchers: one in charge of volumetric measures and the other in charge of planimetric measures. Results: The means of both methods were significantly different between AD and the other two diagnostic groups. In the differential diagnosis of AD against controls, 3D-yrA-H performed significantly better than 2D-yrA-MTL while differences were not statistically significant in the differential diagnosis of AD against MCI. Conclusion: Automated volumetry of the hippocampus is superior to manual planimetry of the MTL in the diagnosis of AD. Nevertheless, the 2D-yrAMTL is a simpler method that could be easily implemented in clinical practice when volumetry is not available.  PMID:27433401

  12. Medial Calcar Support and Radiographic Outcomes of Plate Fixation for Proximal Humeral Fractures

    PubMed Central

    Lin, Shih-Jie; Tsai, Yao-Hung; Yang, Tien-Yu; Shen, Shih-Hsun; Huang, Kuo-Chin; Lee, Mel S.

    2015-01-01

    Plate fixation remains one of the most popular surgical procedures for treating proximal humeral fractures (PHFx); however, substantial rates of complications have been reported in the literature. The objectives of the study were to examine how medial calcar support (MCS) affects the radiographic outcomes and to determine the prognostic factors predicting treatment failure. We performed a retrospective cohort study of 89 adult patients who had PHFx and were treated with plate fixation at our institution in 2007–2011. The enrolled patients were separated into two groups according to disruption of medial calcar. Our results revealed an increased rate of poor radiographic outcomes in patients with disrupted medial calcar. Osteonecrosis of the humeral head and redisplacement were the two radiographic outcomes which had a positive causality with disruption of medial calcar (P = 0.008 and 0.050, resp.). Deficient medial calcar, inadequate reduction, diabetes mellitus, chronic kidney disease, and chronic liver disease were all significant predictors for the development of osteonecrosis in patients after PHFx surgery. Inadequate reduction was also a predictor for redisplacement. We confirmed that the restoration of medial calcar as well as comorbid conditions plays key roles in treatment of patients having PHFx with disrupted medial calcar. PMID:25692132

  13. Medial amygdaloid suppression of predatory attack behavior in the cat: II. Role of a GABAergic pathway from the medial to the lateral hypothalamus.

    PubMed

    Han, Y; Shaikh, M B; Siegel, A

    1996-04-15

    The medial amygdala is known to powerfully suppress predatory attack behavior elicited by electrical stimulation of the lateral hypothalamus of the cat. In the preceding paper, it was shown that the initial limb of a pathway subserving suppression of predatory attack from the medial amygdala to the lateral hypothalamus projects to the ventromedial hypothalamus and its functions are mediated by substance P. The present study tested the hypothesis that the second limb of the pathway subserving medial amygdaloid suppression of predatory attack behavior projects from the medial to lateral hypothalamus and its functions are mediated by GABA. Cannula electrodes were implanted into the lateral hypothalamus for elicitation of predatory attack behavior as well as for the microinfusion of GABA compounds. Monopolar stimulating electrodes were implanted into sites within the medial amygdala from which subseizure levels of stimulation could suppress predatory attack behavior. Initially, the effects of dual stimulation of the medial amygdala and lateral hypothalamus upon response latencies for predatory attack were compared with single stimulation of the lateral hypothalamus alone. Dual stimulation was shown to significantly suppress predatory attack elicited from the lateral hypothalamus. Then, the GABAA receptor antagonist, bicuculline, was microinjected into sites within the lateral hypothalamus from which predatory attack was elicited in doses of 0.015, 0.075 and 0.15 nmol and paired trials of single and dual stimulation were again repeated in a manner identical to that applied prior to drug administration. Drug infusion produced a blockade of medial amygdaloid suppression of predatory attack in a time- and dose-dependent manner. Conversely, microinfusions of the GABAA receptor agonist, muscimol (10, 25 and 50 pmol), into the same lateral hypothalamic 'attack' site in the absence of medial amygdaloid stimulation suppressed predatory attack, thus simulating the effects of

  14. Correlating Function and Imaging Measures of the Medial Longitudinal Fasciculus

    PubMed Central

    Sakaie, Ken; Takahashi, Masaya; Remington, Gina; Wang, Xiaofeng; Conger, Amy; Conger, Darrel; Dimitrov, Ivan; Jones, Stephen; Frohman, Ashley; Frohman, Teresa; Sagiyama, Koji; Togao, Osamu

    2016-01-01

    Objective To test the validity of diffusion tensor imaging (DTI) measures of tissue injury by examining such measures in a white matter structure with well-defined function, the medial longitudinal fasciculus (MLF). Injury to the MLF underlies internuclear ophthalmoparesis (INO). Methods 40 MS patients with chronic INO and 15 healthy controls were examined under an IRB-approved protocol. Tissue integrity of the MLF was characterized by DTI parameters: longitudinal diffusivity (LD), transverse diffusivity (TD), mean diffusivity (MD) and fractional anisotropy (FA). Severity of INO was quantified by infrared oculography to measure versional disconjugacy index (VDI). Results LD was significantly lower in patients than in controls in the medulla-pons region of the MLF (p < 0.03). FA was also lower in patients in the same region (p < 0.0004). LD of the medulla-pons region correlated with VDI (R = -0.28, p < 0.05) as did FA in the midbrain section (R = 0.31, p < 0.02). Conclusions This study demonstrates that DTI measures of brain tissue injury can detect injury to a functionally relevant white matter pathway, and that such measures correlate with clinically accepted evaluation indices for INO. The results validate DTI as a useful imaging measure of tissue integrity. PMID:26800522

  15. Human Medial Frontal Cortex Mediates Unconscious Inhibition of Voluntary Action

    PubMed Central

    Sumner, Petroc; Nachev, Parashkev; Morris, Peter; Peters, Andrew M.; Jackson, Stephen R.; Kennard, Christopher; Husain, Masud

    2007-01-01

    Summary Within the medial frontal cortex, the supplementary eye field (SEF), supplementary motor area (SMA), and pre-SMA have been implicated in the control of voluntary action, especially during motor sequences or tasks involving rapid choices between competing response plans. However, the precise roles of these areas remain controversial. Here, we study two extremely rare patients with microlesions of the SEF and SMA to demonstrate that these areas are critically involved in unconscious and involuntary motor control. We employed masked-prime stimuli that evoked automatic inhibition in healthy people and control patients with lateral premotor or pre-SMA damage. In contrast, our SEF/SMA patients showed a complete reversal of the normal inhibitory effect—ocular or manual—corresponding to the functional subregion lesioned. These findings imply that the SEF and SMA mediate automatic effector-specific suppression of motor plans. This automatic mechanism may contribute to the participation of these areas in the voluntary control of action. PMID:17553420

  16. The Necessity of the Medial Temporal Lobe for Statistical Learning

    PubMed Central

    Schapiro, Anna C.; Gregory, Emma; Landau, Barbara; McCloskey, Michael; Turk-Browne, Nicholas B.

    2014-01-01

    The sensory input that we experience is highly patterned, and we are experts at detecting these regularities. Although the extraction of such regularities, or statistical learning (SL), is typically viewed as a cortical process, recent studies have implicated the medial temporal lobe (MTL), including the hippocampus. These studies have employed fMRI, leaving open the possibility that the MTL is involved but not necessary for SL. Here, we examined this issue in a case study of LSJ, a patient with complete bilateral hippocampal loss and broader MTL damage. In Experiments 1 and 2, LSJ and matched control participants were passively exposed to a continuous sequence of shapes, syllables, scenes, or tones containing temporal regularities in the co-occurrence of items. In a subsequent test phase, the control groups exhibited reliable SL in all conditions, successfully discriminating regularities from recombinations of the same items into novel foil sequences. LSJ, however, exhibited no SL, failing to discriminate regularities from foils. Experiment 3 ruled out more general explanations for this failure, such as inattention during exposure or difficulty following test instructions, by showing that LSJ could discriminate which individual items had been exposed. These findings provide converging support for the importance of the MTL in extracting temporal regularities. PMID:24456393

  17. Developmental Differences in Medial Temporal Lobe Function During Memory Encoding

    PubMed Central

    Ghetti, Simona; DeMaster, Dana M.; Yonelinas, Andrew P.; Bunge, Silvia A.

    2010-01-01

    The ability to recollect details about past events improves during childhood. Most researchers favor the view that this improvement depends largely on the development of the prefrontal cortex (PFC), which is thought to have a protracted course of development relative to the medial temporal lobes (MTL). The primary goal of the present study was to test the hypothesis that the development of detail recollection is also associated with changes in MTL function. We collected functional magnetic resonance imaging (fMRI) data during an incidental encoding task in 80 participants, divided equally across four age groups: 8-year-olds, 10- to 11-year-olds, 14-year-olds, and young adults. Developmental differences in MTL activation profiles were observed. 14-year-olds and adults engaged regions of the hippocampus and posterior parahippocampal gyrus selectively for subsequent detail recollection, whereas 8- and 10- to 11-year-olds did not. In 8-year-olds, these regions were recruited indiscriminately for detail recollection and item recognition, and in 10- to 11-year-olds, activation in these regions did not consistently predict subsequent memory. These results suggest changes in the functional organization of the MTL, such that the hippocampus and posterior parahippocampal gyrus become increasingly specialized for recollection; these changes may be in part responsible for long-term memory improvements during childhood. PMID:20631183

  18. Morphometric Correlation of Impulsivity in Medial Prefrontal Cortex

    PubMed Central

    Cho, Sang Soo; Pellecchia, Giovanna; Aminian, Kelly; Ray, Nicola; Segura, Barbara; Obeso, Ignacio

    2014-01-01

    Impulsivity is a complex behaviour composed of different domains encompassing behavioural disinhibition, risky decision-making and delay discounting abnormalities. To investigate regional brain correlates between levels of individual impulsivity and grey matter volume, we performed voxel-based morphometric correlation analysis in 34 young, healthy subjects using impulsivity scores measured with Barratt Impulsivity Scale-11 and computerized Kirby’s delay discounting task. The VBM analysis showed that impulsivity appears to be reliant on a network of cortical (medial prefrontal cortex and dorsolateral prefrontal cortex) and subcortical (ventral striatum) structures emphasizing the importance of brain networks associated with reward related decision-making in daily life as morphological biomarkers for impulsivity in a normal healthy population. While our results in healthy volunteers may not directly extend to pathological conditions, they provide an insight into the mechanisms of impulsive behaviour in patients with abnormalities in prefrontal/frontal-striatal connections, such as in drug abuse, pathological gambling, ADHD and Parkinson’s disease. PMID:23274773

  19. Structural development and dorsoventral maturation of the medial entorhinal cortex

    PubMed Central

    Ray, Saikat; Brecht, Michael

    2016-01-01

    We investigated the structural development of superficial-layers of medial entorhinal cortex and parasubiculum in rats. The grid-layout and cholinergic-innervation of calbindin-positive pyramidal-cells in layer-2 emerged around birth while reelin-positive stellate-cells were scattered throughout development. Layer-3 and parasubiculum neurons had a transient calbindin-expression, which declined with age. Early postnatally, layer-2 pyramidal but not stellate-cells co-localized with doublecortin – a marker of immature neurons – suggesting delayed functional-maturation of pyramidal-cells. Three observations indicated a dorsal-to-ventral maturation of entorhinal cortex and parasubiculum: (i) calbindin-expression in layer-3 neurons decreased progressively from dorsal-to-ventral, (ii) doublecortin in layer-2 calbindin-positive-patches disappeared dorsally before ventrally, and (iii) wolframin-expression emerged earlier in dorsal than ventral parasubiculum. The early appearance of calbindin-pyramidal-grid-organization in layer-2 suggests that this pattern is instructed by genetic information rather than experience. Superficial-layer-microcircuits mature earlier in dorsal entorhinal cortex, where small spatial-scales are represented. Maturation of ventral-entorhinal-microcircuits – representing larger spatial-scales – follows later around the onset of exploratory behavior. DOI: http://dx.doi.org/10.7554/eLife.13343.001 PMID:27036175

  20. Stochastic interpolation model of the medial superior olive neural circuit.

    PubMed

    Sanda, Pavel; Marsalek, Petr

    2012-01-24

    This article presents a stochastic model of binaural hearing in the medial superior olive (MSO) circuit. This model is a variant of the slope encoding models. First, a general framework is developed describing the elementary neural operations realized on spike trains in individual parts of the circuit and how the neurons converging onto the MSO are connected. Random delay, coincidence detection of spikes, divergence and convergence of spike trains are operations implemented by the following modules: spike generator, jitter generator, and coincidence detector. Subsequent processing of spike trains computes the sound azimuth in the circuit. The circuit parameters that influence efficiency of slope encoding are studied. In order to measure the overall circuit performance the concept of an ideal observer is used instead of a detailed model of higher relays in the auditory pathway. This makes it possible to bridge the gap between psychophysical observations in humans and recordings taken of small rodents. Most of the results are obtained through numerical simulations of the model. PMID:21920505

  1. Medial PFC Damage Abolishes the Self-reference Effect

    PubMed Central

    Philippi, Carissa L.; Duff, Melissa C.; Denburg, Natalie L.; Tranel, Daniel; Rudrauf, David

    2012-01-01

    Functional neuroimaging studies suggest that the medial PFC (mPFC) is a key component of a large-scale neural system supporting a variety of self-related processes. However, it remains unknown whether the mPFC is critical for such processes. In this study, we used a human lesion approach to examine this question. We administered a standard trait judgment paradigm [Kelley, W. M., Macrae, C. N., Wyland, C. L., Caglar, S., Inati, S., & Heatherton, T. F. Finding the self? An event-related fMRI study. Journal of Cognitive Neuroscience, 14, 785–794, 2002] to patients with focal brain damage to the mPFC. The self-reference effect (SRE), a memory advantage conferred by self-related processing, served as a measure of intact self-processing ability. We found that damage to the mPFC abolished the SRE. The results demonstrate that the mPFC is necessary for the SRE and suggest that this structure is important for self-referential processing and the neural representation of self. PMID:21942762

  2. The role of the medial prefrontal cortex in social categorization.

    PubMed

    Molenberghs, Pascal; Morrison, Samantha

    2014-03-01

    Group membership is an important aspect of our everyday behavior. Recently, we showed that existing relevant in-group labels increased activation in the medial prefrontal cortex (MPFC) compared with out-group labels, suggesting a role of the MPFC in social categorization. However, the question still remains whether this increase in MPFC activation for in-group representation is solely related with previous experience with the in-group. To test this, we randomly assigned participants to a red or blue team and in a subsequent functional magnetic resonance imaging experiment they categorized red and blue team words as belonging to either the in-group or the out-group. Results showed that even under these minimal conditions increased activation was found in the MPFC when participants indicated that they belonged to a group, as compared with when they did not. This effect was found to be associated with the level of group identification. These results confirm the role of MPFC in social categorization. PMID:23175678

  3. Decoding Representations of Scenes in the Medial Temporal Lobes

    PubMed Central

    Bonnici, Heidi M; Kumaran, Dharshan; Chadwick, Martin J; Weiskopf, Nikolaus; Hassabis, Demis; Maguire, Eleanor A

    2012-01-01

    Recent theoretical perspectives have suggested that the function of the human hippocampus, like its rodent counterpart, may be best characterized in terms of its information processing capacities. In this study, we use a combination of high-resolution functional magnetic resonance imaging, multivariate pattern analysis, and a simple decision making task, to test specific hypotheses concerning the role of the medial temporal lobe (MTL) in scene processing. We observed that while information that enabled two highly similar scenes to be distinguished was widely distributed throughout the MTL, more distinct scene representations were present in the hippocampus, consistent with its role in performing pattern separation. As well as viewing the two similar scenes, during scanning participants also viewed morphed scenes that spanned a continuum between the original two scenes. We found that patterns of hippocampal activity during morph trials, even when perceptual inputs were held entirely constant (i.e., in 50% morph trials), showed a robust relationship with participants' choices in the decision task. Our findings provide evidence for a specific computational role for the hippocampus in sustaining detailed representations of complex scenes, and shed new light on how the information processing capacities of the hippocampus may influence the decision making process. © 2011 Wiley Periodicals, Inc. PMID:21656874

  4. Medial prefrontal cortex subserves diverse forms of self-reflection.

    PubMed

    Jenkins, Adrianna C; Mitchell, Jason P

    2011-01-01

    The ability to think about oneself--to self--reflect--is one of the defining features of the human mind. Recent research has suggested that this ability may be subserved by a particular brain region: the medial prefrontal cortex (MPFC). However, although humans can contemplate a variety of different aspects of themselves, including their stable personality traits, current feelings, and physical attributes, no research has directly examined the extent to which these different forms of self-reflection are subserved by common mechanisms. To address this question, participants were scanned using functional magnetic resonance imaging (fMRI) while making judgments about their own personality traits, current mental states, and physical attributes as well as those of another person. Whereas some brain regions responded preferentially during only one form of self-reflection, a robust region of MPFC was engaged preferentially during self-reflection across all three types of judgment. These results suggest that--although dissociable--diverse forms of self-referential thought draw on a shared cognitive process subserved by MPFC. PMID:20711940

  5. Theta synchronizes the activity of medial prefrontal neurons during learning.

    PubMed

    Paz, Rony; Bauer, Elizabeth P; Paré, Denis

    2008-07-01

    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 remain unclear. Because the hippocampus projects to the mPFC, we tested whether theta oscillations contribute to synchronize mPFC neurons during learning. Thus, we obtained field (LFP) and unit recordings from multiple mPFC sites during the acquisition of a trace-conditioning task, where a visual conditioned stimulus (CS) predicted reward delivery. In quiet waking, the activity of mPFC neurons was modulated by theta oscillations. During conditioning, CS presentation caused an increase in mPFC theta power that augmented as the CS gained predictive value for reward delivery. This increased theta power coincided with a transient theta phase locking at distributed mPFC sites, an effect that was also manifest in the timing of mPFC unit activity. Overall, these results show that theta oscillations contribute to synchronize neuronal activity at distributed mPFC sites, suggesting that the hippocampus, by generating a stronger theta source during learning, can synchronize mPFC activity, in turn facilitating rhinal transfer of its activity to the neocortex. PMID:18612069

  6. Medial Patellofemoral Ligament Reconstruction in Skeletally Immature Patients

    PubMed Central

    Yercan, Hüseyin Serhat; Kale, Gürler; Erkan, Serkan; Özalp, Taçkın; Okcu, Güvenir

    2014-01-01

    Objectives: To evaluate the clinical outcome after medial patellofemoral ligament (MPFL) reconstruction for patellofemoral instability in skeletally immature patients. Methods: Study participants were 8 patients ( median age, 10 years; range, 5-14 and one male , others female) who had suffered from persistent patellofemoral instability. Our technique preserves femoral and patellar insertion anatomy of MPFL using a free semitendinosus autograft, together with tenodesis to the adductor magnus tendon thus sparing the open physis of distal femur and the patellar attachment of MPFL. The clinical results were evaluated preoperatively and the final follow-up period using the Kujala patellofemoral score. Patellar shift, tilt and height were measured preoperatively and on the latest follow-up on plain radiographs. Results: At average 42 months follow-up ( range, 16 to 56), %80 of patients were satisfied with the treatment. Redislocation or instability symptoms occurred in two patients. No apprehension signs or redislocations were seen in the remanining six patients. A significant improvement (p‹0.05) in Kujala score (from 36 to 77) was found. Patellar shift & tilt decreased to anatomic values in six patients but patella alta persisted. Conclusion: The result of this study show that MPFL reconstruction with our technique seems to be an effective treatment for recurrent and habitual patellofemoral dislocation in skeletally immature patients; leading to significant increases in stability and functionality.

  7. Bilateral superior rectus transposition for congenital exotropia associated with anomalous medial rectus muscles.

    PubMed

    Kodsi, Sylvia R

    2015-10-01

    Superior rectus transposition to the lateral rectus insertion without inferior rectus transposition has been used to correct esotropic deviations secondary to Duane syndrome and abducens nerve palsy. This is usually combined with an augmented posterior fixation suture of the superior rectus muscle to the lateral rectus muscle and ipsilateral medial rectus recession. We report a child with a large-angle congenital exotropia who was found to have anomalous medial rectus muscles bilaterally. Bilateral superior rectus transposition to the medial rectus insertion with bilateral lateral rectus recessions achieved good ocular alignment in primary position. PMID:26486030

  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. Discoid medial meniscus with a horizontal cleavage tear: a juvenile who suffered for 3 years.

    PubMed

    Chen, Jingqing; Gao, Shijun; Chen, Baicheng

    2012-09-01

    It is very rare to see medial discoid meniscus, and there have been only 82 knees in 61 cases reported to date. The investigators found discoid medial meniscus with horizontal cleavage tear in a 13-year-old juvenile who had been injured while playing basketball, and endured for 3 years. Both magnetic resonance images and the arthroscopic findings were presented. Saucerization of the torn discoid medial meniscus was performed successfully, and the clinical outcomes were satisfying according to the follow-up of 14 months. PMID:21912338

  10. Comparison of fMRI BOLD response patterns by electrical stimulation of the ventroposterior complex and medial thalamus of the rat.

    PubMed

    Yang, Pai-Feng; Chen, You-Yin; Chen, Der-Yow; Hu, James W; Chen, Jyh-Horng; Yen, Chen-Tung

    2013-01-01

    The objective of this study was to compare the functional connectivity of the lateral and medial thalamocortical pain pathways by investigating the blood oxygen level-dependent (BOLD) activation patterns in the forebrain elicited by direct electrical stimulation of the ventroposterior (VP) and medial (MT) thalamus. An MRI-compatible stimulation electrode was implanted in the VP or MT of α-chloralose-anesthetized rats. Electrical stimulation was applied to the VP or MT at various intensities (50 µA to 300 µA) and frequencies (1 Hz to 12 Hz). BOLD responses were analyzed in the ipsilateral forelimb region of the primary somatosensory cortex (iS1FL) after VP stimulation and in the ipsilateral cingulate cortex (iCC) after MT stimulation. When stimulating the VP, the strongest activation occurred at 3 Hz. The stimulation intensity threshold was 50 µA and the response rapidly peaked at 100 µA. When stimulating the MT, The optimal frequency for stimulation was 9 Hz or 12 Hz, the stimulation intensity threshold was 100 µA and we observed a graded increase in the BOLD response following the application of higher intensity stimuli. We also evaluated c-Fos expression following the application of a 200-µA stimulus. Ventroposterior thalamic stimulation elicited c-Fos-positivity in few cells in the iS1FL and caudate putamen (iCPu). Medial thalamic stimulation, however, produced numerous c-Fos-positive cells in the iCC and iCPu. The differential BOLD responses and c-Fos expressions elicited by VP and MT stimulation indicate differences in stimulus-response properties of the medial and lateral thalamic pain pathways. PMID:23826146

  11. Comparison of fMRI BOLD Response Patterns by Electrical Stimulation of the Ventroposterior Complex and Medial Thalamus of the Rat

    PubMed Central

    Yang, Pai-Feng; Chen, You-Yin; Chen, Der-Yow; Hu, James W.; Chen, Jyh-Horng; Yen, Chen-Tung

    2013-01-01

    The objective of this study was to compare the functional connectivity of the lateral and medial thalamocortical pain pathways by investigating the blood oxygen level-dependent (BOLD) activation patterns in the forebrain elicited by direct electrical stimulation of the ventroposterior (VP) and medial (MT) thalamus. An MRI-compatible stimulation electrode was implanted in the VP or MT of α-chloralose-anesthetized rats. Electrical stimulation was applied to the VP or MT at various intensities (50 µA to 300 µA) and frequencies (1 Hz to 12 Hz). BOLD responses were analyzed in the ipsilateral forelimb region of the primary somatosensory cortex (iS1FL) after VP stimulation and in the ipsilateral cingulate cortex (iCC) after MT stimulation. When stimulating the VP, the strongest activation occurred at 3 Hz. The stimulation intensity threshold was 50 µA and the response rapidly peaked at 100 µA. When stimulating the MT, The optimal frequency for stimulation was 9 Hz or 12 Hz, the stimulation intensity threshold was 100 µA and we observed a graded increase in the BOLD response following the application of higher intensity stimuli. We also evaluated c-Fos expression following the application of a 200-µA stimulus. Ventroposterior thalamic stimulation elicited c-Fos-positivity in few cells in the iS1FL and caudate putamen (iCPu). Medial thalamic stimulation, however, produced numerous c-Fos-positive cells in the iCC and iCPu. The differential BOLD responses and c-Fos expressions elicited by VP and MT stimulation indicate differences in stimulus-response properties of the medial and lateral thalamic pain pathways. PMID:23826146

  12. Where the brain grows old: decline in anterior cingulate and medial prefrontal function with normal aging.

    PubMed

    Pardo, José V; Lee, Joel T; Sheikh, Sohail A; Surerus-Johnson, Christa; Shah, Hemant; Munch, Kristin R; Carlis, John V; Lewis, Scott M; Kuskowski, Michael A; Dysken, Maurice W

    2007-04-15

    Even healthy adults worry about declines in mental efficiency with aging. Subjective changes in mental flexibility, self-regulation, processing speed, and memory are often cited. We show here that focal decreases in brain activity occur with normal aging as measured with fluorodeoxyglucose and positron emission tomography. The largest declines localize to a medial network including the anterior cingulate/medial prefrontal cortex, dorsomedial thalamus, and sugenual cingulate/basal forebrain. Declining metabolism in this network correlates with declining cognitive function. The medial prefrontal metabolic changes with aging are similar in magnitude to the hypometabolism found in Mild Cognitive Impairment or Alzheimer's disease. These results converge with data from healthy elderly indicating dysfunction in the anterior attention system. The interaction of attention in the anterior cingulate cortex with memory in the medial temporal lobe may explain the global impairment that defines dementia. Despite the implications for an aging population, the neurophysiologic mechanisms of these metabolic decreases remain unknown. PMID:17321756

  13. Unilateral Resection of the Anterior Medial Temporal Lobe Impairs Odor Identification and Valence Perception

    PubMed Central

    Juran, Stephanie A.; Lundström, Johan N.; Geigant, Michael; Kumlien, Eva; Fredrikson, Mats; Åhs, Fredrik; Olsson, Mats J.

    2016-01-01

    The anterior medial temporal lobe (TL), including the amygdala, has been implicated in olfactory processing, e.g., coding for intensity and valence, and seems also involved in memory. With this background, the present study evaluated whether anterior medial TL-resections in TL epilepsy affected intensity and valence ratings, as well as free and cued identification of odors. These aspects of odor perception were assessed in 31 patients with unilateral anterior medial TL-resections (17 left, 14 right) and 16 healthy controls. Results suggest that the anterior medial TL is in particular necessary for free, but also cued, odor identification. TL resection was also found to impair odor valence, but not intensity ratings. Left resected patients rated nominally pleasant and unpleasant odors as more neutral suggesting a special role for the left anterior TL in coding for emotional saliency in response to odors. PMID:26779109

  14. Medial thigh pain: An unusual presentation of giant calculi in sigmoid neobladder

    PubMed Central

    Abrol, Nitin; Gupta, Narmada; Kumar, Rajeev

    2011-01-01

    Calculi in a neobladder usually present with irritative lower urinary tract symptoms, flank pain, and haematuria. We report a case of giant stones in a sigmoid neobladder, who presented with medial thigh pain. PMID:21814323

  15. Open reduction of medial epicondyle fractures: operative tips for technical ease.

    PubMed

    Kamath, Atul F; Cody, Stephanie R; Hosalkar, Harish S

    2009-08-01

    In the pediatric population, medial humeral epicondylar fractures account for nearly 12% of all elbow fractures. There is ongoing debate about the surgical management of medial epicondyle fracture cases. Our technique in the operative management of medial epicondyle fractures uses the external application of an Esmarch bandage, as well as provisional fixation with needle rather than K-wire fixation. This technique decreases the need for soft-tissue release and, therefore, theoretically, maintains soft-tissue vascularity of the small fracture fragments. Moreover, it preserves the soft-tissue tension medially. It involves the use of a bandage that is universally available in orthopedic operating rooms, including those in developing nations. It is easy to apply by either the principal or assisting surgeon. With practice, it cuts down operative time and can help substitute for an assistant. This relatively simple operative technique makes for a more seamless operative process, improved reduction, and key preservation of soft-tissue vascularity. PMID:19506930

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

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

  17. Unilateral Resection of the Anterior Medial Temporal Lobe Impairs Odor Identification and Valence Perception.

    PubMed

    Juran, Stephanie A; Lundström, Johan N; Geigant, Michael; Kumlien, Eva; Fredrikson, Mats; Åhs, Fredrik; Olsson, Mats J

    2015-01-01

    The anterior medial temporal lobe (TL), including the amygdala, has been implicated in olfactory processing, e.g., coding for intensity and valence, and seems also involved in memory. With this background, the present study evaluated whether anterior medial TL-resections in TL epilepsy affected intensity and valence ratings, as well as free and cued identification of odors. These aspects of odor perception were assessed in 31 patients with unilateral anterior medial TL-resections (17 left, 14 right) and 16 healthy controls. Results suggest that the anterior medial TL is in particular necessary for free, but also cued, odor identification. TL resection was also found to impair odor valence, but not intensity ratings. Left resected patients rated nominally pleasant and unpleasant odors as more neutral suggesting a special role for the left anterior TL in coding for emotional saliency in response to odors. PMID:26779109

  18. Medial prefrontal cortex stimulation modulates the processing of conditioned fear

    PubMed Central

    Guhn, Anne; Dresler, Thomas; Andreatta, Marta; Müller, Laura D.; Hahn, Tim; Tupak, Sara V.; Polak, Thomas; Deckert, Jürgen; Herrmann, Martin J.

    2014-01-01

    The extinction of conditioned fear depends on an efficient interplay between the amygdala and the medial prefrontal cortex (mPFC). In rats, high-frequency electrical mPFC stimulation has been shown to improve extinction by means of a reduction of amygdala activity. However, so far it is unclear whether stimulation of homologues regions in humans might have similar beneficial effects. Healthy volunteers received one session of either active or sham repetitive transcranial magnetic stimulation (rTMS) covering the mPFC while undergoing a 2-day fear conditioning and extinction paradigm. Repetitive TMS was applied offline after fear acquisition in which one of two faces (CS+ but not CS−) was associated with an aversive scream (UCS). Immediate extinction learning (day 1) and extinction recall (day 2) were conducted without UCS delivery. Conditioned responses (CR) were assessed in a multimodal approach using fear-potentiated startle (FPS), skin conductance responses (SCR), functional near-infrared spectroscopy (fNIRS), and self-report scales. Consistent with the hypothesis of a modulated processing of conditioned fear after high-frequency rTMS, the active group showed a reduced CS+/CS− discrimination during extinction learning as evident in FPS as well as in SCR and arousal ratings. FPS responses to CS+ further showed a linear decrement throughout both extinction sessions. This study describes the first experimental approach of influencing conditioned fear by using rTMS and can thus be a basis for future studies investigating a complementation of mPFC stimulation to cognitive behavioral therapy (CBT). PMID:24600362

  19. [Medial posteroventral pallidotomy for the treatment of Parkinson's disease].

    PubMed

    Krauss, J K; Grossman, R G; Lai, E C; Schwartz, K; Jankovic, J

    1997-01-01

    Stereotactic medial posteroventral pallidotomy for treatment of Parkinson's disease attracts increasing attention. We report on the preliminary results of 12 patients at 1 year after microelectrode-guided unilateral pallidotomy. The primary indications were severe bradykinesia and levodopa-induced dyskinesias. After radiofrequency lesioning all patients had immediate improvement of contralateral parkinsonian signs. Postoperative magnetic resonance imaging confirmed the localization of the lesions. At the 1-year follow-up, all patients had sustained benefit. The global improvement was rated as moderate in six cases, and as marked in six other cases. The mean values of various subscores of the Unified Parkinson's Disease Rating Scale (UPDRS) showed highly significant changes in the "off" state (pre/postoperatively): UPDRS Motor score (60.3/31). UPDRS Activities of Daily Living (ADL) score (33.2/18.3), gait/postural stability score (13.8/7.0), and subscores for contralateral rigidity (4.9/2.1), tremor (7.1/1.4) and bradykinesia (11.6/5.3). There was also significant improvement of ipsilateral bradykinesia and rigidity. Furthermore, we found significant changes of the mean values of the UPDRS ADL and motor "on" scores, an increase of the percentage of "on" time with reduced on-off fluctuations, and a decrease of the percentage of levodopa-induced dyskinesias, with marked improvement or complete abolition of contralateral dyskinesias in particular. The preoperative levodopa regimen was maintained, in general, or only slightly modified, if necessary. Two patients had transient complications: one patient suffered postoperative pneumonia and altered mental status; another patient displayed mild Broca's aphasia secondary to a small stroke involving the dorsal thalamus and the adjacent white matter. There were no persistent side effects at the 1-year follow-up. Contemporary unilateral pallidotomy is an effective and promising therapeutical option for surgical treatment of

  20. Noradrenergic control of error perseveration in medial prefrontal cortex.

    PubMed

    Caetano, Marcelo S; Jin, Lu E; Harenberg, Linda; Stachenfeld, Kimberly L; Arnsten, Amy F T; Laubach, Mark

    2012-01-01

    The medial prefrontal cortex (mPFC) plays a key role in behavioral variability, action monitoring, and inhibitory control. The functional role of mPFC may change over the lifespan due to a number of aging-related issues, including dendritic regression, increased cAMP signaling, and reductions in the efficacy of neuromodulators to influence mPFC processing. A key neurotransmitter in mPFC is norepinephrine. Previous studies have reported aging-related changes in the sensitivity of mPFC-dependent tasks to noradrenergic agonist drugs, such as guanfacine. Here, we assessed the effects of yohimbine, an alpha-2 noradrenergic antagonist, in cohorts of younger and older rats in a classic test of spatial working memory (using a T-maze). Older rats (23-29 mo.) were impaired by a lower dose of yohimbine compared to younger animals (5-10 mo.). To determine if the drug acts on alpha-2 noradrenergic receptors in mPFC and if its effects are specific to memory-guided performance, we made infusions of yohimbine into mPFC of a cohort of young rats (6 mo.) using an operant delayed response task. The task involved testing rats in blocks of trials with memory- and stimulus-guided performance. Yohimbine selectively impaired memory-guided performance and was associated with error perseveration. Infusions of muscimol (a GABA-A agonist) at the same sites also selectively impaired memory-guided performance, but did not lead to error perseveration. Based on these results, we propose several potential interpretations for the role for the noradrenergic system in the performance of delayed response tasks, including the encoding of previous response locations, task rules (i.e., using a win-stay strategy instead of a win-shift strategy), and performance monitoring (e.g., prospective encoding of outcomes). PMID:23293590

  1. Disconnection Between Amygdala and Medial Prefrontal Cortex in Psychotic Disorders.

    PubMed

    Mukherjee, Prerona; Sabharwal, Amri; Kotov, Roman; Szekely, Akos; Parsey, Ramin; Barch, Deanna M; Mohanty, Aprajita

    2016-07-01

    Distracting emotional information impairs attention more in schizophrenia (SCZ) than in never-psychotic individuals. However, it is unclear whether this impairment and its neural circuitry is indicative generally of psychosis, or specifically of SCZ, and whether it is even more specific to certain SCZ symptoms (eg, deficit syndrome). It is also unclear if this abnormality contributes to impaired behavioral performance and real-world functioning. Functional imaging data were recorded while individuals with SCZ, bipolar disorder with psychosis (BDP) and no history of psychotic disorders (CON) attended to identity of faces while ignoring their emotional expressions. We examined group differences in functional connectivity between amygdala, involved in emotional evaluation, and sub-regions of medial prefrontal cortex (MPFC), involved in emotion regulation and cognitive control. Additionally, we examined correlation of this connectivity with deficit syndrome and real-world functioning. Behaviorally, SCZ showed the worst accuracy when matching the identity of emotional vs neutral faces. Neurally, SCZ showed lower amygdala-MPFC connectivity than BDP and CON. BPD did not differ from CON, neurally or behaviorally. In patients, reduced amygdala-MPFC connectivity during emotional distractors was related to worse emotional vs neutral accuracy, greater deficit syndrome severity, and unemployment. Thus, reduced amygdala-MPFC functional connectivity during emotional distractors reflects a deficit that is specific to SCZ. This reduction in connectivity is associated with worse clinical and real-world functioning. Overall, these findings provide support for the specificity and clinical utility of amygdala-MPFC functional connectivity as a potential neural marker of SCZ. PMID:26908926

  2. Medial Prefrontal Cortex: Adding Value to Imagined Scenarios

    PubMed Central

    Lin, Wen-Jing; Horner, Aidan J.; Bisby, James A.; Burgess, Neil

    2016-01-01

    The medial prefrontal cortex (mPFC) is consistently implicated in the network supporting autobiographical memory. Whereas more posterior regions in this network have been related to specific processes, such as the generation of visuospatial imagery or the association of items and contexts, the functional contribution of the mPFC remains unclear. However, the involvement of mPFC in estimation of value during decision-making suggests that it might play a similar role in memory. We investigated whether mPFC activity reflects the subjective value of elements in imagined scenarios. Participants in an MRI scanner imagined scenarios comprising a spatial context, a physiological state of need (e.g., thirst), and two items that could be congruent (e.g., drink) or incongruent (e.g., food) with the state of need. Memory for the scenarios was tested outside the scanner. Our manipulation of subjective value by imagined need was verified by increased subjective ratings of value for congruent items and improved subsequent memory for them. Consistent with our hypothesis, fMRI signal in mPFC reflected the modulation of an item’s subjective value by the imagined physiological state, suggesting the mPFC selectively tracked subjective value within our imagination paradigm. Further analyses showed uncorrected effects in non-mPFC regions, including increased activity in the insula when imagining states of need, the caudate nucleus when imagining congruent items, and the anterior hippocampus/amygdala when imagining subsequently remembered items. We therefore provide evidence that the mPFC plays a role in constructing the subjective value of the components of imagined scenarios and thus potentially in reconstructing the value of components of autobiographical recollection. PMID:26042501

  3. Medial Frontal White and Gray Matter Contributions to General Intelligence

    PubMed Central

    Bouix, Sylvain; Kubicki, Marek

    2014-01-01

    The medial orbitofrontal cortex (mOFC) and rostral anterior cingulate cortex (rACC) are part of a wider neural network that plays an important role in general intelligence and executive function. We used structural brain imaging to quantify magnetic resonance gray matter volume and diffusion tensor white matter integrity of the mOFC-rACC network in 26 healthy participants who also completed neuropsychological tests of intellectual abilities and executive function. Stochastic tractography, the most effective Diffusion Tensor Imaging method for examining white matter connections between adjacent gray matter regions, was employed to assess the integrity of mOFC-rACC pathways. Fractional anisotropy (FA), which reflects the integrity of white matter connections, was calculated. Results indicated that higher intelligence correlated with greater gray matter volumes for both mOFC and rACC, as well as with increased FA for left posterior mOFC-rACC connectivity. Hierarchical regression analyses revealed that DTI-derived FA of left posterior mOFC-rACC uniquely accounted for 29%–34% of the variance in IQ, in comparison to 11%–16% uniquely explained by gray matter volume of the left rACC. Together, left rACC gray matter volume and white matter connectivity between left posterior mOFC and rACC accounted for up to 50% of the variance in general intelligence. This study is to our knowledge the first to examine white matter connectivity between OFC and ACC, two gray matter regions of interests that are very close in physical proximity, and underscores the important independent contributions of variations in rACC gray matter volume and mOFC-rACC white matter connectivity to individual differences in general intelligence. PMID:25551572

  4. Medial olivocochlear efferent reflex inhibition of human cochlear nerve responses.

    PubMed

    Lichtenhan, J T; Wilson, U S; Hancock, K E; Guinan, J J

    2016-03-01

    Inhibition of cochlear amplifier gain by the medial olivocochlear (MOC) efferent system has several putative roles: aiding listening in noise, protection against damage from acoustic overexposure, and slowing age-induced hearing loss. The human MOC reflex has been studied almost exclusively by measuring changes in otoacoustic emissions. However, to help understand how the MOC system influences what we hear, it is important to have measurements of the MOC effect on the total output of the organ of Corti, i.e., on cochlear nerve responses that couple sounds to the brain. In this work we measured the inhibition produced by the MOC reflex on the amplitude of cochlear nerve compound action potentials (CAPs) in response to moderate level (52-60 dB peSPL) clicks from five, young, normal hearing, awake, alert, human adults. MOC activity was elicited by 65 dB SPL, contralateral broadband noise (CAS). Using tympanic membrane electrodes, approximately 10 h of data collection were needed from each subject to yield reliable measurements of the MOC reflex inhibition on CAP amplitudes from one click level. The CAS produced a 16% reduction of CAP amplitude, equivalent to a 1.98 dB effective attenuation (averaged over five subjects). Based on previous reports of efferent effects as functions of level and frequency, it is possible that much larger effective attenuations would be observed at lower sound levels or with clicks of higher frequency content. For a preliminary comparison, we also measured MOC reflex inhibition of DPOAEs evoked from the same ears with f2's near 4 kHz. The resulting effective attenuations on DPOAEs were, on average, less than half the effective attenuations on CAPs. PMID:26364824

  5. Visualization of the medial forebrain bundle using diffusion tensor imaging

    PubMed Central

    Hana, Ardian; Hana, Anisa; Dooms, Georges; Boecher-Schwarz, Hans; Hertel, Frank

    2015-01-01

    Diffusion tensor imaging is a technique that enables physicians the portrayal of white matter tracts in vivo. We used this technique in order to depict the medial forebrain bundle (MFB) in 15 consecutive patients between 2012 and 2015. Men and women of all ages were included. There were six women and nine men. The mean age was 58.6 years (39–77). Nine patients were candidates for an eventual deep brain stimulation. Eight of them suffered from Parkinson‘s disease and one had multiple sclerosis. The remaining six patients suffered from different lesions which were situated in the frontal lobe. These were 2 metastasis, 2 meningiomas, 1 cerebral bleeding, and 1 glioblastoma. We used a 3DT1-sequence for the navigation. Furthermore T2- and DTI- sequences were performed. The FOV was 200 × 200 mm2, slice thickness 2 mm, and an acquisition matrix of 96 × 96 yielding nearly isotropic voxels of 2 × 2 × 2 mm. 3-Tesla-MRI was carried out strictly axial using 32 gradient directions and one b0-image. We used Echo-Planar-Imaging (EPI) and ASSET parallel imaging with an acceleration factor of 2. b-value was 800 s/mm2. The maximal angle was 50°. Additional scanning time was < 9 min. We were able to visualize the MFB in 12 of our patients bilaterally and in the remaining three patients we depicted the MFB on one side. It was the contralateral side of the lesion. These were 2 meningiomas and one metastasis. Portrayal of the MFB is possible for everyday routine for neurosurgical interventions. As part of the reward circuitry it might be of substantial importance for neurosurgeons during deep brain stimulation in patients with psychiatric disorders. Surgery in this part of the brain should always take the preservation of this white matter tract into account. PMID:26581828

  6. Noradrenergic control of error perseveration in medial prefrontal cortex

    PubMed Central

    Caetano, Marcelo S.; Jin, Lu E.; Harenberg, Linda; Stachenfeld, Kimberly L.; Arnsten, Amy F. T.; Laubach, Mark

    2013-01-01

    The medial prefrontal cortex (mPFC) plays a key role in behavioral variability, action monitoring, and inhibitory control. The functional role of mPFC may change over the lifespan due to a number of aging-related issues, including dendritic regression, increased cAMP signaling, and reductions in the efficacy of neuromodulators to influence mPFC processing. A key neurotransmitter in mPFC is norepinephrine. Previous studies have reported aging-related changes in the sensitivity of mPFC-dependent tasks to noradrenergic agonist drugs, such as guanfacine. Here, we assessed the effects of yohimbine, an alpha-2 noradrenergic antagonist, in cohorts of younger and older rats in a classic test of spatial working memory (using a T-maze). Older rats (23–29 mo.) were impaired by a lower dose of yohimbine compared to younger animals (5–10 mo.). To determine if the drug acts on alpha-2 noradrenergic receptors in mPFC and if its effects are specific to memory-guided performance, we made infusions of yohimbine into mPFC of a cohort of young rats (6 mo.) using an operant delayed response task. The task involved testing rats in blocks of trials with memory- and stimulus-guided performance. Yohimbine selectively impaired memory-guided performance and was associated with error perseveration. Infusions of muscimol (a GABA-A agonist) at the same sites also selectively impaired memory-guided performance, but did not lead to error perseveration. Based on these results, we propose several potential interpretations for the role for the noradrenergic system in the performance of delayed response tasks, including the encoding of previous response locations, task rules (i.e., using a win-stay strategy instead of a win-shift strategy), and performance monitoring (e.g., prospective encoding of outcomes). PMID:23293590

  7. Detached Anterior Horn of the Medial Meniscus Mimicking a Parameniscal Cyst

    PubMed Central

    Fukuta, Shoji; Tsutsui, Takahiko; Matsuura, Tetsuya; Suzue, Naoto; Hamada, Daisuke; Goto, Tomohiro; Sairyo, Koichi

    2015-01-01

    We report a case of a detached anterior horn of the medial meniscus with anterior knee pain. Preoperative magnetic resonance images of the knee were initially interpreted as a parameniscal cyst. Arthroscopic examination revealed subluxation of the anterior horn of the medial meniscus due to detachment from its anterior tibial insertion. Arthroscopic fixation with a suture anchor was successful and the cystic lesion was no longer visible on postoperative images. PMID:26550510

  8. Stimulation of the medial plantar nerve for complex regional pain syndrome.

    PubMed

    Mobbs, Ralph J; Lazarro, Amanda

    2010-11-01

    We describe a 47-year old male with complex regional pain syndrome II in the distribution of the medial plantar nerve following metatarsal fracture, which was treated with peripheral nerve stimulation. Using a new technique of nerve stimulation with a percutaneous-type electrode, the patient experienced sustained relief at 12 months follow-up. To our knowledge, this is the first report of peripheral neurostimulation effectively managing pain for the medial plantar nerve. PMID:20708936

  9. Functional dissociation between lateral and medial entorhinal cortex in memory processes in mice.

    PubMed

    Gauthier, M; Destrade, C; Soumireu-Mourat, B

    1983-07-01

    The effects of lesions of the medial or the lateral entorhinal cortex in mice were examined on acquisition, retention and extinction of an operant-conditioning task in a Skinner box. Compared with the control animals, lesions in the medial entorhinal had no behavioral effects whereas lesions in the lateral entorhinal enhanced retention and increased resistance to extinction but did not change acquisition of this task. These results suggest a functional dissociation between the two parts of the entorhinal cortex. PMID:6882517

  10. Endoscopic endonasal versus transfacial approach for blowout fractures of the medial orbital wall.

    PubMed

    Pagnoni, Mario; Giovannetti, Filippo; Amodeo, Giulia; Priore, Paolo; Iannetti, Giorgio

    2015-05-01

    In the last decades, the introduction of computed tomography has allowed an increase in the number of diagnosed fractures of the medial orbital wall. To repair medial wall fractures, many surgical techniques have been proposed (1), each one with its advantages and disadvantages. In this study, we compared endoscopic endonasal and transcutaneous reduction approaches in terms of surgery time and clinical outcome. Between 2001 and 2005, 81 patients with orbital wall fractures were treated at our department. Among these 81 patients, 24 (29.63%) were affected by a medial orbital fracture. Patients with fracture to both floor and medial walls underwent floor reduction by a transcutaneous subpalpebral approach (n = 9, 11.1%), whereas patients with isolated medial wall fracture underwent medial wall reduction by a transcutaneous subpalpebral approach using alloplastic implants (n = 8, 9.88%) or were treated by endoscopic approach (n = 5, 6.17%). After surgery, oculomotor function improved in all 22 patients. None of the patients had complications. Computed tomography revealed a well-consolidated site of fracture in both endoscopic endonasal and transcutaneous approaches. The average operating time for endoscopic endonasal and transfacial approach was 50 and 45 minutes, respectively. In this paper, the author proposed a results comparison between the endoscopic approach and the transcutaneous one. PMID:25974823

  11. [Anatomical variants of the medial calcaneal nerve and the Baxter nerve in the tarsal tunnel].

    PubMed

    Martín-Oliva, X; Elgueta-Grillo, J; Veliz-Ayta, P; Orosco-Villaseñor, S; Elgueta-Grillo, M; Viladot-Perice, R

    2013-01-01

    The tarsal tunnel is composed of the posterior border of the medial malleoulus, the posterior aspect of the talus and the medial aspect of the calcaneus. The medial calcaneal nerve emerges from the posterior aspect of the posterior tibial nerve in 75% of cases and from the lateral plantar nerve in the remaining 25%. Finally, the medial calcaneal nerve ends as a single terminal branch in 79% of cases and in numerous terminal branches in the remaining 21%. To describe the anatomical variants of the posterior tibial nerve and its terminal branches. To describe the steps for tarsal tunnel release. To describe Baxter nerve release. The anatomical variants of the posterior tibial nerve and its terminal branches within the tarsal tunnel were studied. Then the Lam technique was performed; it consists of: 1) opening of the laciniate ligament, 2) opening of the fascia over the abductor hallucis muscle, 3) exoneurolysis of the posterior tibial nerve and its terminal branches, identifying the emergence and pathway of the medial calcaneal branch, the lateral plantar nerve and its Baxter nerve branch and the medial plantar nerve. Baxter nerve was found in 100% of cases. In 100% of cases in our series the nerve going to the abductor digiti minimi muscle of the foot was found; 87.5% of cases had two terminal branches. The dissections proved that a crucial step was the release of the distal tarsal tunnel. PMID:24701749

  12. Dual role of medial A10 dopamine neurons in affective encoding.

    PubMed

    Liu, Zhong-Hua; Shin, Rick; Ikemoto, Satoshi

    2008-11-01

    Increasing evidence suggests that the activation of medial A10 neurons mediates positive affective encoding. However, little is known about the functions of the inhibition of midbrain dopamine neurons. Here we show evidence suggesting that the inhibition of medial A10 neurons mediates a negative affective state, leading to negative affective encoding, whereas blunting the activation of medial A10 neurons disrupts positive affective encoding involving food reward. We used a microinjection procedure, in which the D(2) dopamine receptor agonist quinpirole was administered into the cell body region of the dopamine neurons, a procedure that reduces dopamine cell firing. Microinjections of quinpirole into the posteromedial ventral tegmental area, but not its more lateral counterparts, led to conditioned place aversion. Quinpirole administration to this site also decreased food intake and basal dopamine concentration in the ventromedial striatum, a major projection area of medial A10 neurons. In addition, moderate quinpirole doses that did not lead to conditioned place aversion or disrupt food intake abolished food-conditioned place preference, suggesting that blunting dopamine impulse activity in response to food reward disrupts positive affective encoding in associated external stimuli. Our data support the hypothesis that activation of medial A10 dopamine neurons mediates a positive affective state, leading to positive affective encoding, while their inhibition mediates a negative affective state, leading to negative affective encoding. Together with previous findings, we propose that medial A10 neurons are an important component of the mechanism via which animals learn to avoid negative incentive stimuli. PMID:18256592

  13. In Vivo Measurement of Rotator Cuff Tear Tension: Medial Versus Lateral Footprint Position.

    PubMed

    Dierckman, Brian D; Wang, David W; Bahk, Michael S; Burns, Joseph P; Getelman, Mark H

    2016-01-01

    We conducted a study to evaluate in vivo tension applied to the rotator cuff tendon positioned at the medial versus lateral footprint during arthroscopic rotator cuff repair. We evaluated 20 consecutive patients who underwent arthroscopic rotator cuff repair. During repair, a grasper was inserted through a lateral portal, and a digital weigh scale was attached. The tendon was grasped and translated to the medial footprint, and tension recorded. After a relaxation period, the tendon edge was translated to the lateral footprint, and tension recorded. Mean (SD) tension was 0.41 (0.33) pound when tendons were positioned at the medial footprint and 2.21 (1.20) pounds when they were positioned at the lateral footprint, representing a 5.4-fold difference (P < .0001). For smaller tears (≤20 mm anterior-posterior), 7.6 times less tension was applied to the tendons when pulled to the medial versus lateral footprint. For larger tears, 4.1 times less tension was applied to the tendons when pulled to the medial versus lateral footprint. This study demonstrated a significant, 5.4-fold increase in tension when the tendon edge was reduced to the lateral as opposed to the medial footprint in vivo. PMID:26991588

  14. Intralaminar and medial thalamic influence on cortical synchrony, information transmission and cognition

    PubMed Central

    Saalmann, Yuri B.

    2014-01-01

    The intralaminar and medial thalamic nuclei are part of the higher-order thalamus, which receives little sensory input, and instead forms extensive cortico-thalamo-cortical pathways. The large mediodorsal thalamic nucleus predominantly connects with the prefrontal cortex, the adjacent intralaminar nuclei connect with fronto-parietal cortex, and the midline thalamic nuclei connect with medial prefrontal cortex and medial temporal lobe. Taking into account this connectivity pattern, it is not surprising that the intralaminar and medial thalamus has been implicated in a variety of cognitive functions, including memory processing, attention and orienting, as well as reward-based behavior. This review addresses how the intralaminar and medial thalamus may regulate information transmission in cortical circuits. A key neural mechanism may involve intralaminar and medial thalamic neurons modulating the degree of synchrony between different groups of cortical neurons according to behavioral demands. Such a thalamic-mediated synchronization mechanism may give rise to large-scale integration of information across multiple cortical circuits, consequently influencing the level of arousal and consciousness. Overall, the growing evidence supports a general role for the higher-order thalamus in the control of cortical information transmission and cognitive processing. PMID:24847225

  15. Medial Amygdala Lesions Selectively Block Aversive Pavlovian–Instrumental Transfer in Rats

    PubMed Central

    McCue, Margaret G.; LeDoux, Joseph E.; Cain, Christopher K.

    2014-01-01

    Pavlovian conditioned stimuli (CSs) play an important role in the reinforcement and motivation of instrumental active avoidance (AA). Conditioned threats can also invigorate ongoing AA responding [aversive Pavlovian–instrumental transfer (PIT)]. The neural circuits mediating AA are poorly understood, although lesion studies suggest that lateral, basal, and central amygdala nuclei, as well as infralimbic prefrontal cortex, make key, and sometimes opposing, contributions. We recently completed an extensive analysis of brain c-Fos expression in good vs. poor avoiders following an AA test (Martinez et al., 2013, Learning and Memory). This analysis identified medial amygdala (MeA) as a potentially important region for Pavlovian motivation of instrumental actions. MeA is known to mediate defensive responding to innate threats as well as social behaviors, but its role in mediating aversive Pavlovian–instrumental interactions is unknown. We evaluated the effect of MeA lesions on Pavlovian conditioning, Sidman two-way AA conditioning (shuttling) and aversive PIT in rats. Mild footshocks served as the unconditioned stimulus in all conditioning phases. MeA lesions had no effect on AA but blocked the expression of aversive PIT and 22 kHz ultrasonic vocalizations in the AA context. Interestingly, MeA lesions failed to affect Pavlovian freezing to discrete threats but reduced freezing to contextual threats when assessed outside of the AA chamber. These findings differentiate MeA from lateral and central amygdala, as lesions of these nuclei disrupt Pavlovian freezing and aversive PIT, but have opposite effects on AA performance. Taken together, these results suggest that MeA plays a selective role in the motivation of instrumental avoidance by general or uncertain Pavlovian threats. PMID:25278858

  16. Sex and laterality differences in medial amygdala neurons and astrocytes of adult mice.

    PubMed

    Pfau, Daniel R; Hobbs, Nicholas J; Breedlove, S Marc; Jordan, Cynthia L

    2016-08-15

    The posterodorsal aspect of the medial amygdala (MePD) in rats is sexually dimorphic, being larger and containing more and larger neurons in males than in females. It is also highly lateralized, with the right MePD larger than the left in both sexes, but with the smaller left MePD actually containing more and larger neurons than the larger right. Astrocytes are also strikingly sexually differentiated, with male-biased numbers and lateralized favoring the right in the rat MePD. However, comparable information is scant for mice where genetic tools offer greater experimental power. Hence, we examined the MePD from adult male and female C57Bl/6(J) mice. We now report that the MePD is larger in males than in females, with the MePD in males containing more astrocytes and neurons than in females. However, we did not find sex differences in astrocyte complexity or overall glial number nor effects of laterality in either measure. While the mouse MePD is generally less lateralized than in rats, we did find that the sex difference in astrocyte number is only on the right because of a significant lateralization in females, with significantly fewer astrocytes on the right than the left but only in females. A sex difference in neuronal soma size favoring males was also evident, but only on the left. Sex differences in the number of neurons and astrocytes common to both rodent species may represent core morphological features that critically underlie the expression of sex-specific behaviors that depend on the MePD. J. Comp. Neurol. 524:2492-2502, 2016. © 2016 Wiley Periodicals, Inc. PMID:26780286

  17. Surgical results of the slipped medial rectus muscle after hang back recession surgery

    PubMed Central

    Duranoglu, Yasar; Ilhan, Hatice Deniz; Guler Alis, Meryem

    2014-01-01

    AIM To analyze the surgical results of a slipped medial rectus muscle (MRM) after hang back recession surgery for esotropia. METHODS Twenty-one patients who underwent re-exploration for diagnosed slipped muscle after hang back recession surgery were included in this retrospective study. Dynamic magnetic resonance imaging was performed to identify the location of the slipped muscle. Ocular motility was evaluated with assessment with prism and cover test in gaze at cardinal positions. The operations were performed by the same consultant. Intraoperative forced duction test was performed under general anesthesia. The empty sheath of the slipped MRM was resected and the muscle was advanced to the original insertion site in all patients. RESULTS The average age of 21 patients who had consecutive exotropia with a slipped MRM at the time of presentation was 17.4±5.4y (5-50y). The average duration between the first operation and the diagnosis of the slipped muscle was 25mo (12 to 36mo). The mean follow up after the corrective surgery was 28mo. The mean preoperative adduction limitation in the field of action of the slipped muscle was -2.26 (ranging from -1 to -4). All patients had full adduction postoperatively. CONCLUSION The diagnosis of the slipped muscle should be confirmed during the strabismus surgery. The slipped muscle may be caused due to insufficient suture and excessive rubbing of the eye. When divergent strabismus is observed after the recession of the MRM, a slipped muscle should be considered in the differential diagnosis. PMID:25540761

  18. 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

  19. A SEX COMPARISON OF THE ANATOMY AND FUNCTION OF THE MAIN OLFACTORY BULB-MEDIAL AMYGDALA PROJECTION IN MICE

    PubMed Central

    Kang, Ningdong; McCarthy, Elizabeth A.; Cherry, James A.; Baum, Michael J.

    2010-01-01

    We previously reported that some main olfactory bulb (MOB) mitral/tufted (M/T) cells send a direct projection to the ‘vomeronasal’ amygdala in female mice and selectively respond to volatile male mouse urinary odors. We asked whether MOB M/T cells that project to the vomeronasal amygdala exist in male mice and whether there is a sexually dimorphic response of these neurons to volatile male urinary pheromones. Gonadectomized male and female mice received bilateral injections of the retrograde tracer, Cholera toxin-B (CTb) into the medial amygdala (Me), which is part of the vomeronasal amygdala. All subjects were then treated with estradiol benzoate and progesterone before being exposed to volatile male urinary odors whereupon they were sacrificed 90 min later. Sections of the MOB were immunostained for Fos protein and/or CTb. Male mice, like females, displayed a small population of MOB M/T cells that project to the Me. While the general localization of these cells was similar in the two sexes, there were statistically significant sex differences in the percentage of MOB M/T cells in the anterior and posterior medial segments of the MOB that were retrogradely labeled by CTb. Male urinary volatiles stimulated equivalent, significant increases in Fos expression by MOB M/T neurons projecting to the Me in the two sexes. By contrast, in the same mice exposure to male urinary volatiles stimulated a significant increase in Fos expression by mitral cells in the accessory olfactory bulb (AOB) only in female subjects. Thus any sexually dimorphic behavioral or neuroendocrine responses to male urinary volatiles likely depend on the differential processing of these odor inputs in the AOB and/or other downstream forebrain structures after their detection by the main olfactory system. PMID:21070839

  20. Structural reorganization of pyramidal neurons in the medial prefrontal cortex of alcohol dependent rats is associated with altered glial plasticity

    PubMed Central

    Kim, Airee; Zamora-Martinez, Eva R.; Edwards, Scott; Mandyam, Chitra D.

    2014-01-01

    In rodents, chronic intermittent ethanol vapor exposure (CIE) produces alcohol dependence, alters the activity of pyramidal neurons and decreases the number of glial progenitors in the medial prefrontal cortex (mPFC). Adult male Wistar rats were exposed to CIE and were injected with mitotic markers to label and phenotype proliferating cells to test the hypothesis that CIE produces concurrent alterations in the structure of pyramidal neurons and the cell cycle kinetics and developmental stages of glial progenitors in the mPFC. Medial prefrontal cortical tissue was processed for Golgi-Cox staining, immunohistochemistry and Western blotting analysis. CIE increased dendritic arborization and spine densities within basal and apical dendrites of pyramidal neurons via aberrant reorganization of actin cytoskeleton-associated molecules. CIE concomitantly increased expression of total NR2B subunits without affecting phosphorylation of NR2B at Tyr-1472 or levels of PSD-95. CIE reduced the length of S phase of the cell cycle of glial progenitors and reduced proliferation and differentiation of progenitors into bHLH transcription factor Olig2-expressing premyelinating oligodendrocyte progenitor cells (OPCs). CIE also produced a corresponding hyperphosphorylation of Olig2, and reduced expression of myelin basic protein. Our findings demonstrate that CIE-induced alterations in OPCs and myelin-related proteins are associated with profound alterations in the structure of pyramidal neurons. In sum, our results not only provide evidence that alcohol dependence leads to pathological changes in the mPFC, which may in part define a cellular basis for cognitive impairments associated with alcoholism, but also show dependence-associated morphological changes in the PFC at the single neuron level. PMID:24667898

  1. Structural reorganization of pyramidal neurons in the medial prefrontal cortex of alcohol dependent rats is associated with altered glial plasticity.

    PubMed

    Kim, Airee; Zamora-Martinez, Eva R; Edwards, Scott; Mandyam, Chitra D

    2015-01-01

    In rodents, chronic intermittent ethanol vapor exposure (CIE) produces alcohol dependence, alters the activity of pyramidal neurons and decreases the number of glial progenitors in the medial prefrontal cortex (mPFC). Adult male Wistar rats were exposed to CIE and were injected with mitotic markers to label and phenotype proliferating cells to test the hypothesis that CIE produces concurrent alterations in the structure of pyramidal neurons and the cell cycle kinetics and developmental stages of glial progenitors in the mPFC. Medial prefrontal cortical tissue was processed for Golgi-Cox staining, immunohistochemistry and Western blotting analysis. CIE increased dendritic arborization and spine densities within basal and apical dendrites of pyramidal neurons via aberrant reorganization of actin cytoskeleton-associated molecules. CIE concomitantly increased the expression of total NR2B subunits without affecting phosphorylation of NR2B at Tyr-1472 or levels of PSD-95. CIE reduced the length of S-phase of the cell cycle of glial progenitors and reduced proliferation and differentiation of progenitors into bHLH transcription factor Olig2-expressing premyelinating oligodendrocyte progenitor cells (OPCs). CIE also produced a corresponding hyperphosphorylation of Olig2, and reduced expression of myelin basic protein. Our findings demonstrate that CIE-induced alterations in OPCs and myelin-related proteins are associated with profound alterations in the structure of pyramidal neurons. In sum, our results not only provide evidence that alcohol dependence leads to pathological changes in the mPFC, which may in part define a cellular basis for cognitive impairments associated with alcoholism, but also show dependence-associated morphological changes in the PFC at the single neuron level. PMID:24667898

  2. CONTRIBUTION TO THE ANATOMICAL STUDY OF THE CORTICOPERIOSTEAL FLAP OF THE MEDIAL FEMORAL CONDYLE

    PubMed Central

    Andrade, Rômulo Guimarães; Bufáiçal, Henrique Gubert; Oliveira, Leandro Alves de; Souza, Fabiano Inácio de; Kuwae, Mário Yoshihide; Teixeira da Silva, João Alírio

    2015-01-01

    Objective: to perform the anatomical study, in cadavers, of the corticoperiosteal flap of the medial femoral condyle, based on the medial genicular artery, evaluating challenges in dissection and the topographic patterns. Materials and methods: fifteen limbs from eight cadavers were studied, ages ranging from 19 to 74 years old. They were placed at supine position, and a longitudinal incision on the medial face of the lower part of the thigh was performed, exposing medial vastus and sartorius muscles, with descendent genicular vessels being also exposed. The distance between the descendent genicular artery and the medial articular line of the knee, the diameter of the vessel, the length of the pedicle, and the presence of the fasciocutaneous branch and its location were analyzed. Results: the distance between the origin of the descendent genicular artery and the medial articular line of the knee ranged from 11.2cm to 14.5cm, with an average of 12.63cm. The mean artery diameter was 2.5mm (from 2.25mm to 2.75mm). The distance between the descendent genicular artery and the fasciocutaneous branch ranged from 1.0 to 1.5cm. The mean length of the vascular pedicle was 7.01cm, ranging from 5.6cm to 8.6cm. Conclusion: the corticoperiosteal flap of the medial femoral condyle of the knee is easy to dissect, presents a constant vascular pedicle, with average length of 7.0cm and diameter of 2.5mm, enabling it to be indicated for microsurgical transplants. PMID:27004187

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

    PubMed

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

    2015-02-26

    Understanding degeneration of biological and prosthetic knee joints requires knowledge of the in-vivo loading environment during activities of daily living. Musculoskeletal models can estimate medial/lateral tibiofemoral compartment contact forces, yet anthropometric differences between individuals make accurate predictions challenging. We developed a full-body OpenSim musculoskeletal model with a knee joint that incorporates subject-specific tibiofemoral alignment (i.e. knee varus-valgus) and geometry (i.e. contact locations). We tested the accuracy of our model and determined the importance of these subject-specific parameters by comparing estimated to measured medial and lateral contact forces during walking in an individual with an instrumented knee replacement and post-operative genu valgum (6°). The errors in the predictions of the first peak medial and lateral contact force were 12.4% and 11.9%, respectively, for a model with subject-specific tibiofemoral alignment and contact locations determined through radiographic analysis, vs. 63.1% and 42.0%, respectively, for a model with generic parameters. We found that each degree of tibiofemoral alignment deviation altered the first peak medial compartment contact force by 51N (r(2)=0.99), while each millimeter of medial-lateral translation of the compartment contact point locations altered the first peak medial compartment contact force by 41N (r(2)=0.99). The model, available at www.simtk.org/home/med-lat-knee/, enables the specification of subject-specific joint alignment and compartment contact locations to more accurately estimate medial and lateral tibiofemoral contact forces in individuals with non-neutral alignment. PMID:25595425

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2016-01-01

    With the high prevalence of pediatric obesity there is a need for structured physical activity during childhood. However, altered tibiofemoral loading during physical activity in obese children likely contribute to their increased risk of orthopedic disorders of the knee. The goal of this study was to determine the effects of pediatric obesity and walking duration on medial and lateral tibiofemoral contact forces. We collected experimental biomechanics data during treadmill walking at 1 m•s(-1) for 20 min in 10 obese and 10 healthy-weight 8-12 year-olds. We created subject-specific musculoskeletal models using radiographic measures of tibiofemoral alignment and centers-of-pressure, and predicted medial and lateral tibiofemoral contact forces at the beginning and end of each trial. Obesity and walking duration affected tibiofemoral loading. At the beginning of the trail, the average percent of the total load passing through the medial compartment during stance was 85% in the obese children and 63% in the healthy-weight children; at the end of the trial, the medial distribution was 90% in the obese children and 72% in the healthy-weight children. Medial compartment loading rates were 1.78 times greater in the obese participants. The medial compartment loading rate increased 17% in both groups at the end compared to the beginning of the trial (p = 0.001). We found a strong linear relationship between body-fat percentage and the medial-lateral load distribution (r(2) = 0.79). Altered tibiofemoral loading during walking in obese children may contribute to their increased risk of knee pain and pathology. PMID:26271943

  6. Detecting emotion in others: increased insula and decreased medial prefrontal cortex activation during emotion processing in elite adventure racers.

    PubMed

    Thom, Nathaniel J; Johnson, Douglas C; Flagan, Taru; Simmons, Alan N; Kotturi, Sante A; Van Orden, Karl F; Potterat, Eric G; Swain, Judith L; Paulus, Martin P

    2014-02-01

    Understanding the neural processes that characterize elite performers is a first step to develop a neuroscience model that can be used to improve performance in stressful circumstances. Adventure racers are elite athletes that operate in small teams in the context of environmental and physical extremes. In particular, awareness of team member's emotional status is critical to the team's ability to navigate high-magnitude stressors. Thus, this functional magnetic resonance imaging (fMRI) study examined the hypothesis that adventure racers would show altered emotion processing in brain areas that are important for resilience and social awareness. Elite adventure racers (n = 10) were compared with healthy volunteers (n = 12) while performing a simple emotion face-processing (modified Hariri) task during fMRI. Across three types of emotional faces, adventure racers showed greater activation in right insula, left amygdala and dorsal anterior cingulate. Additionally, compared with healthy controls adventure racers showed attenuated right medial prefrontal cortex activation. These results are consistent with previous studies showing elite performers differentially activate neural substrates underlying interoception. Thus, adventure racers differentially deploy brain resources in an effort to recognize and process the internal sensations associated with emotions in others, which could be advantageous for team-based performance under stress. PMID:23171614

  7. Differential central projections of vestibular afferents in pigeons

    NASA Technical Reports Server (NTRS)

    Dickman, J. D.; Fang, Q.

    1996-01-01

    The question of whether a differential distribution of vestibular afferent information to central nuclear neurons is present in pigeons was studied using neural tracer compounds. Discrete tracing of afferent fibers innervating the individual semicircular canal and otolith organs was produced by sectioning individual branches of the vestibular nerve that innervate the different receptor organs and applying crystals of horseradish peroxidase, or a horseradish peroxidase/cholera toxin mixture, or a biocytin compound for neuronal uptake and transport. Afferent fibers and their terminal distributions within the brainstem and cerebellum were visualized subsequently. Discrete areas in the pigeon central nervous system that receive primary vestibular input include the superior, dorsal lateral, ventral lateral, medial, descending, and tangential vestibular nuclei; the A and B groups; the intermediate, medial, and lateral cerebellar nuclei; and the nodulus, the uvula, and the paraflocculus. Generally, the vertical canal afferents projected heavily to medial regions in the superior and descending vestibular nuclei as well as the A group. Vertical canal projections to the medial and lateral vestibular nuclei were observed but were less prominent. Horizontal canal projections to the superior and descending vestibular nuclei were much more centrally located than those of the vertical canals. A more substantial projection to the medial and lateral vestibular nuclei was seen with horizontal canal afferents compared to vertical canal fibers. Afferents innervating the utricle and saccule terminated generally in the lateral regions of all vestibular nuclei in areas that were separate from the projections of the semicircular canals. In addition, utricular fibers projected to regions in the vestibular nuclei that overlapped with the horizontal semicircular canal terminal fields, whereas saccular afferents projected to regions that received vertical canal fiber terminations. Lagenar

  8. 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

  9. Radiographic measures of settlement phenomenon in patients with medial compartment knee osteoarthritis.

    PubMed

    Dong, Tianhua; Chen, Wei; Zhang, Fei; Yin, Bing; Tian, Ye; Zhang, Yingze

    2016-06-01

    In this study, we proposed for the first time the theory of "settlement phenomenon" in tibial plateau and carefully explored the role of settlement of tibial plateau in the occurrence and progression of medial compartment knee osteoarthritis (OA) through investigating the relationship between the degree of settlement and the radiographic severity of OA. One hundred twenty-seven patients with knee medial compartment OA were recruited and examined with weight-bearing radiographs of the entire lower limb. The radiographic severity of OA was evaluated using the Kellgren and Lawrence (KL) grading methods. The settlement value, hip-knee-ankle angle, minimum medial joint space width, and condylar plateau angle were measured at the same time. The settlement value increases with the upgrading of KL grades (r = 0.352, P < 0.001) and is significantly correlated with the changes of hip-knee-ankle angle, minimum medial joint space width, and condylar plateau angle (r = -0.527, -0.271, and 0.415, P < 0.001, respectively). These results suggest that the settlement of tibial plateau could be an evaluable indicator of medial compartment knee OA and be used in the early diagnosis and progression of OA. PMID:26712497

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

    NASA Technical Reports Server (NTRS)

    Rigby, David L.

    2004-01-01

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

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

    PubMed Central

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

    2006-01-01

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

  12. The medial-lateral force distribution in the ovine stifle joint during walking.

    PubMed

    Taylor, William R; Poepplau, Berry M; König, Christian; Ehrig, Rainald M; Zachow, Stefan; Duda, Georg N; Heller, Markus O

    2011-04-01

    Knowledge of the load distribution in the knee is essential for understanding the interaction between mechanics and biology in both the healthy and diseased joint. While the sheep stifle joint is a predominant model for better understanding regeneration after injury, little is known about the compartmental force distribution between the medial and lateral condyles. By including sheep specific anatomy and gait analyses, we used computational musculoskeletal analyses to estimate the medial-lateral joint contact force distribution in ovine stifle joints during walking by simplifying the system of equations into a 2D problem that was solved directly. Gait analysis was conducted using bone markers in three female Merino-mix sheep. Joint contact forces were computed with respect to the specific anatomy of the ovine tibia, resulting in low (<0.13 bodyweight) mean anteroposterior shear forces throughout the gait cycle, with mean peak contact forces perpendicular to the tibial plateau of 2.2 times bodyweight. The medial-lateral compartmental load distribution across the tibial condyles was determined and revealed loading predominantly on the medial condyle, bearing approximately 75% of the total load during phases of peak loading. By considering the anatomical characteristics of the ovine stifle joint, together with the dynamic forces during gait, this study provides evidence for predominantly medial loading in sheep, somewhat similar to the distribution reported in man. However, the exact conditions under which the loading in the ovine stifle joint is representative of the human situation will need to be elucidated in further studies. PMID:20957731

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

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

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

  14. [Morphological rationale for medial facetectomy during microsurgical removal of herniated lumbar disks].

    PubMed

    Kushniruk, P I; dreval', O N

    2006-01-01

    The study was undertaken to provide an anatomic and morphological rationale for the use of medial facetectomy in the microsurgical treatment of herniated lumbar disks and to assess the results of performed operations. Morphological studies were conducted on corpses, by comparing coronal and transverse sections of the lumbar spine. The concept "nervous root canal" was used during the study. The detected features of the anatomical and topographic structure of the nervous root canal permitted the substantiation of the necessity and volume of medial facetectomy at different levels. When an approach is applied into the discal area, the highest and least volume of bone resection at medial facetectomy is required at the levels of L3-L4 and L5-S1, respectively. The clinical study involved an analysis of the results of microsurgical treatment of 530 patients with herniated lumbar disks. The analysis of clinical findings revealed that medial facetectomy had been used during 382 (72%) operations. When the operations were performed at different levels, the usage of this technique differs: at the levels of L3-L4, L4-L5, and L5-S1 in 30 (100%), 206 (91%), and 145 (53%) cases, respectively. The data on the usage of medial facetectomy during operations correspond to the revealed specific features of the anatomic and topographic structure of the nervous root canal at each of the operated levels. PMID:16739929

  15. Ankle inversion taping using kinesiology tape for treating medial ankle sprain in an amateur soccer player.

    PubMed

    Lee, Sun-Min; Lee, Jung-Hoon

    2015-07-01

    [Purpose] The purpose of this study was to report the effects of ankle inversion taping using kinesiology tape in a patient with a medial ankle sprain. [Subject] A 28-year-old amateur soccer player suffered a Grade 2 medial ankle sprain during a match. [Methods] Ankle inversion taping was applied to the sprained ankle every day for 2 months. [Results] His symptoms were reduced after ankle inversion taping application for 2 months. The self-reported function score, the reach distances in the Star Excursion Balance Test, and the weight-bearing ankle dorsiflexion were increased. [Conclusion] This study showed that ankle inversion taping using kinesiology tape may be an effective therapy for a patient with a medial ankle sprain. PMID:26311991

  16. Aneurysmal bone cyst of medial cuneiform and a novel surgical technique for mid-foot reconstruction

    PubMed Central

    Sampath Kumar, Venkatesan; Jalan, Divesh; Khan, Shah Alam; Mridha, Asit Ranjan

    2014-01-01

    Aneurysmal bone cyst of the foot is extremely rare and the involvement of medial cuneiform has never been reported in the literature. In this report, we describe a 15-year-old boy who presented with a 6-month history of pain and swelling in his left foot. Radiograph demonstrated a lytic lesion in the medial cuneiform extending on to the middle cuneiform, the navicular bone and the base of the first metatarsal. En bloc resection of the lesion was performed using a dorsal longitudinal incision along the first ray. Tricortical iliac crest graft was harvested and shaped to fill the defect. Two drill holes were made and the tibialis anterior tendon was attached to the graft. Prepared, morcellised allograft was placed along the junction of autograft and host bone. At 1-year follow-up, the patient was pain free, the medial arch of the foot was maintained and the graft had united with the host bone. PMID:24563041

  17. Ankle inversion taping using kinesiology tape for treating medial ankle sprain in an amateur soccer player

    PubMed Central

    Lee, Sun-Min; Lee, Jung-Hoon

    2015-01-01

    [Purpose] The purpose of this study was to report the effects of ankle inversion taping using kinesiology tape in a patient with a medial ankle sprain. [Subject] A 28-year-old amateur soccer player suffered a Grade 2 medial ankle sprain during a match. [Methods] Ankle inversion taping was applied to the sprained ankle every day for 2 months. [Results] His symptoms were reduced after ankle inversion taping application for 2 months. The self-reported function score, the reach distances in the Star Excursion Balance Test, and the weight-bearing ankle dorsiflexion were increased. [Conclusion] This study showed that ankle inversion taping using kinesiology tape may be an effective therapy for a patient with a medial ankle sprain. PMID:26311991

  18. Exertional Compartment Syndrome of the Medial Foot Compartment: Diagnosis and Treatment.

    PubMed

    Izadi, Faye E; Richie Jr, Douglas H

    2014-06-25

    Abstract Exertional compartment syndrome (ECS) in the foot is rarely reported and often confused with plantar fasciitis as a cause of arch pain in the running athlete. We describe a case involving a 19 year old competitive collegiate runner who developed a chronic case of bilateral medial arch pain during training, which was initially diagnosed as plantar fasciitis but failed to respond to conventional treatment. After symptoms began to suggest exertional compartment syndrome, the diagnosis was confirmed by measuring an elevated resting pressure in the medial compartment of both feet. The patient underwent a bilateral medial compartment fasciotomy, which allowed a full return to activity, and has remained pain free after a one year follow up. PMID:24963970

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

    PubMed

    Izadi, Faye E; Richie, Douglas H

    2014-07-01

    Exertional compartment syndrome in the foot is rarely reported and often confused with plantar fasciitis as a cause of arch pain in the running athlete. We describe a case involving a 19-year-old competitive collegiate runner who developed a chronic case of bilateral medial arch pain during training, which was initially diagnosed as plantar fasciitis but failed to respond to conventional treatment. After symptoms began to suggest exertional compartment syndrome, the diagnosis was confirmed by measuring an elevated resting pressure in the medial compartment of both feet. The patient underwent a bilateral medial compartment fasciotomy, which allowed a full return to activity, and has remained pain free after a 1-year follow-up. PMID:25076087

  20. Fornix and medial temporal lobe lesions lead to comparable deficits in complex visual perception.

    PubMed

    Lech, Robert K; Koch, Benno; Schwarz, Michael; Suchan, Boris

    2016-05-01

    Recent research dealing with the structures of the medial temporal lobe (MTL) has shifted away from exclusively investigating memory-related processes and has repeatedly incorporated the investigation of complex visual perception. Several studies have demonstrated that higher level visual tasks can recruit structures like the hippocampus and perirhinal cortex in order to successfully perform complex visual discriminations, leading to a perceptual-mnemonic or representational view of the medial temporal lobe. The current study employed a complex visual discrimination paradigm in two patients suffering from brain lesions with differing locations and origin. Both patients, one with extensive medial temporal lobe lesions (VG) and one with a small lesion of the anterior fornix (HJK), were impaired in complex discriminations while showing otherwise mostly intact cognitive functions. The current data confirmed previous results while also extending the perceptual-mnemonic theory of the MTL to the main output structure of the hippocampus, the fornix. PMID:26994782

  1. Radiographic Relevance of the Distal Medial Cuneiform Angle in Hallux Valgus Assessment.

    PubMed

    Hatch, Daniel J; Smith, Abigail; Fowler, Troy

    2016-01-01

    The angle formed by the distal articular facet of the medial cuneiform has been evaluated and discussed by various investigators. However, no consistent method has been available to radiograph and measure this entity. The wide variability of the angle is not conducive to comparative analysis. Additionally, investigators have noted that the angles observed (obliquity) vary greatly because of changes in radiographic angle, foot position, rotation of the first ray, and declination of the first metatarsal. Recognizing that these variables exist, we propose a reproducible assessment using digital radiography and application of deformity of correction principles. Our results have indicated a mean distal medial cuneiform angle of 20.69° in normal feet, 23.51° with moderate hallux valgus, and 20.41° with severe hallux valgus deformity. The radiograph beam was kept at 15° from the coronal plane. An inverse relationship was found between the distal medial cuneiform angle and bunion severity. This was in contrast to our expected hypothesis. The overall angle of the first metatarsal-medial cuneiform did, however, correlate with the severity of the bunion deformity (p < .000). The obliquity values and intermetatarsal angles changed in direct relationship to the radiographic projection angle. This illustrates the importance of using standardized radiographic projection angles. We conclude that the 1-dimensional standard anteroposterior radiograph with assessment of the distal medial cuneiform angle cannot adequately demonstrate the pathologic features of hallux valgus. A better indicator appears to be the first metatarsal-medial cuneiform angle. This pathologic entity is a 3-dimensional one that incorporates the joint morphology of the first ray, triplane osseous positioning, and soft tissue imbalances. Perhaps, 3-dimensional computed tomography imaging will provide better insight into this entity. PMID:26359620

  2. Ostectomy and Medial Plantar Artery Flap Reconstruction for Charcot Foot Ulceration Involving the Midfoot.

    PubMed

    Sato, Tomoya; Ichioka, Shigeru

    2016-01-01

    Charcot foot is a serious complication of diabetes, characterized by deformity and overlying ulceration. The condition most commonly affects the midfoot. However, little information is available on the use of a medial plantar artery flap to treat diabetic midfoot ulceration. The purpose of the present study was to evaluate the versatility of ostectomy and medial plantar flap reconstruction for midfoot plantar ulceration associated with rocker-bottom deformity secondary to Charcot foot. Four patients underwent ostectomy and medial plantar flap reconstruction. Before flap reconstruction, the devitalized soft tissues and bone were radically resected. After the infection had been controlled, the ulcerated portion was minimally excised, and the bony prominence underlying the ulcer was removed. A medial plantar artery flap was applied to the ulcer. The donor site was covered with a split-thickness skin graft or artificial dermis. In all patients, the ulcers healed and independent ambulation was achieved. However, 1 patient experienced ulcer recurrence, and subsequent infection necessitated a major amputation. Limb salvage is challenging in the setting of deformity and intractable plantar ulceration. The advantages of medial plantar artery flap reconstruction are that tissues with a rich blood supply are used to cover the exposed bone, and the flap can withstand the pressure and shear stress of the patient's body weight. However, a dominant artery in the foot is sacrificed. Therefore, the patency of the dorsalis pedis artery must be confirmed in every patient. The results of the present study have demonstrated that a medial plantar artery can be an effective alternative for diabetic patients with a plantar ulcer secondary to Charcot foot. PMID:26190780

  3. Experience Rate of Elbow Pain and Morphological Abnormality of Humeral Medial Epicondyle among Youth Baseball Players

    PubMed Central

    Kotoura, Yoshihiro; Morihara, Toru; Kida, Yoshikazu; Sukenari, Tsuyoshi; Furukawa, Ryuhei; Kabuto, Yukichi; MInami, Masataka; Onishi, Okihiro; Tsujihara, Takashi; Hojo, Tatsuya; Fujiwara, Hiroyoshi; Kubo, Toshikazu

    2016-01-01

    Objectives: The aim of this study was to investigate the experience rate of elbow pain and to clarify the relationship between morphological abnormality of the humeral medial epicondyle and positions among baseball players in elementary school (ES), junior high school (JHS) and high school (HS). Methods: In this study, 4353 baseball players who participated in our medical screening (2008-2015) were enrolled. There were 1545 players from ES, 1934 players from JHS, and 874 players from HS. We asked them to answer the questionnaire to investigate the experience of elbow pain, and the position they played. Ultrasonography of the humeral medial epicondyle was examined and irregularity, fragmentation, and malunion of the humeral medial epicondyle. The results were analyzed statistically. P < 0.05 was considered significant for all statistical analyses. Results: The experience rates of elbow pain among players in ES, JHS, and HS were 26.0%, 27.0%, and 68.3%. The rates of abnormality of humeral medial epicondyle among players in ES, JHS, and HS were 18.2%, 36.3%, and 39.9% (Table 1). The experience rate of elbow pain among pitchers and catchers was significantly higher than the fielders in ES (Table 2), however, there were no significant differences between positions in JHS and HS (Table 3,4). According to the rate of morphological abnormalities of humeral medial epicondyle, pitchers and catchers were significantly higher than fielders in ES, while only pitchers were significantly higher than the fielders in JHS and HS (Table 2,3,4). Conclusion: The experience rate of elbow pain among baseball players rose as the age increased, and the rate in HS was almost 70%. The rates of morphological abnormality of humeral medial epicondyle among pitchers and catchers were high and the tendency was observed from a young age. The primary prevention of elbow injuries in youth baseball players of all ages should be considered.

  4. Differentiated Staffing.

    ERIC Educational Resources Information Center

    Scobey, Mary-Margaret, Ed.; Fiorino, A. John, Ed.

    This book is a collection of six articles that deal with the concept and the practice of differentiated staffing in education. Included in the collection are articles on the concept itself; on problems, prospects, and the practical implementation of the concept; staff differentiation in a multiunit school; and polemical aspects of differentiated…

  5. Differential games.

    NASA Technical Reports Server (NTRS)

    Varaiya, P. P.

    1972-01-01

    General discussion of the theory of differential games with two players and zero sum. Games starting at a fixed initial state and ending at a fixed final time are analyzed. Strategies for the games are defined. The existence of saddle values and saddle points is considered. A stochastic version of a differential game is used to examine the synthesis problem.

  6. 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

  7. Mechanism of the Rapid Effect of 17β -Estradiol on Medial Amygdala Neurons

    NASA Astrophysics Data System (ADS)

    Nabekura, Junichi; Oomura, Yutaka; Minami, Taketsugu; Mizuno, Yuji; Fukuda, Atsuo

    1986-07-01

    The mechanism by which sex steroids rapidly modulate the excitability of neurons was investigated by intracellular recording of neurons in rat medial amygdala brain slices. Brief hyperpolarization and increased potassium conductance were produced by 17β - estradiol. This effect persisted after elimination of synaptic input and after suppression of protein synthesis. Thus, 17β -estradiol directly changes the ionic conductance of the postsynaptic membrane of medial amygdala neurons. In addition, a greater proportion of the neurons from females than from males responded to 17β -estradiol.

  8. Misdiagnosis of plexiform neurofibroma of the medial plantar nerve: case report.

    PubMed

    D'Orazi, Valerio; Venditto, Teresa; Panunzi, Andrea; Anichini, Silvia; Manzini, Gabriele; Tallarico, Arturo; Bernetti, Andrea; Paoloni, Marco

    2014-09-01

    Plexiform neurofibromas are benign tumors of the peripheral nerve. Diagnosis may be challenging, if they present mimicking other peripheral nerve pathologies. We report the case of a patient who had severe foot pain, which progressively hampered her walking ability, erroneously attributed to recurrent Morton's neuroma. Diagnosis of plexiform neurofibroma of her right medial plantar nerve was made 15 years after the appearance of symptoms. Pain and function recovered after radical neurotomy of the medial plantar nerve. A correct diagnosis is an essential starting point in the treatment of neurofibromas and a misdiagnosis may lead to an inappropriate treatment. PMID:25024003