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Sample records for differentiate medial meniscal

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

    PubMed Central

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

    2015-01-01

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

  2. Ultrasound assessment of medial meniscal extrusion: a validation study using MRI as reference standard.

    PubMed

    Nogueira-Barbosa, Marcello H; Gregio-Junior, Everaldo; Lorenzato, Mario M; Guermazi, Ali; Roemer, Frank W; Chagas-Neto, Francisco A; Crema, Michel D

    2015-03-01

    OBJECTIVE. The purpose of this article is to validate both semiquantitative and quantitative ultrasound assessment of medial meniscal extrusion using MRI assessment as the reference standard. SUBJECTS AND METHODS. Ninety-three consecutive patients with chronic knee pain referred for knee MRI were evaluated by ultrasound and MRI on the same day. Two musculoskeletal radiologists assessed meniscal extrusion on ultrasound and MRI separately and independently and graded it semiquantitatively as follows: 0 (< 2 mm), 1 (≥ 2 mm and < 4 mm), and 2 (≥ 4 mm). Agreement between the ultrasound and MRI evaluations was determined using weighted kappa statistics. Intraclass correlation coefficients were used to evaluate agreement using the absolute values of extrusion (quantitative assessment). We further evaluated the diagnostic performance of ultrasound for the detection of medial meniscal extrusion using MRI as the reference standard. RESULTS. For semiquantitative grading, agreement between ultrasound and MRI was moderate for reader 1 (κ = 0.57) and substantial for reader 2 (κ = 0.64). Substantial agreement was found for both readers (intraclass correlation coefficients, 0.73 and 0.70) when comparing quantitative assessment of meniscal extrusion between ultrasound and MRI. Ultrasound showed excellent sensitivity (95% and 96% for each reader) and good specificity (82% and 70% for each reader) in the detection of meniscal extrusion. CONCLUSION. Ultrasound assessment of meniscal extrusion is reliable and can be used for both quantitative and semiquantitative assessment, exhibiting excellent diagnostic performance for the detection of meniscal extrusion compared with MRI.

  3. Pressure distributions on the medial tibial plateau after medial meniscal surgery and tibial plateau levelling osteotomy in dogs.

    PubMed

    Pozzi, A; Litsky, A S; Field, J; Apelt, D; Meadows, C; Johnson, K A

    2008-01-01

    To evaluate the effect of medial meniscal release (MMR) and medial, caudal pole hemimeniscectomy (MCH) on pressure distribution in the cranial cruciate ligament (CCL) deficient canine stifle, and with tibial plateau levelling osteotomy (TPLO). Twelve adult dogs. In experiment one, six pairs of cadaveric canine stifles with an intact CCL were axially loaded with a servo-hydraulic material testing machine and pressure distributions were mapped and quantified using pressure sensitive films. Axial loading of each joint was then repeated following MMR, and again after MCH. In experiment two, six pairs of cadaveric canine stifles with or without TPLO were tested before and after CCL transection, and each MMR and MCH procedure using the same methods of experiment 1. In experiment one, MMR and MCH had significant effects on the pressure distribution resulting in a 2.5-fold increase in the percentage of surface area with pressure higher than 10 MPa. In experiment two, CCL transection resulted in a significant change in pressure distribution only in the stifle without TPLO (P<0.05). Both MMR and MCH resulted in a 1.7-fold increase in the percentage of area with peak pressure in the stifle with TPLO (P<0.05). Meniscal surgery results in a change in pressure distribution and magnitude within the medial compartment of the stifle. Compromised function of the meniscus by either MMR or MCH result in stress concentration which may predispose to osteoarthritis.

  4. Arthroscopically assisted medial meniscal allograft transplantation using a modified bone plug to facilitate passage: surgical technique.

    PubMed

    Kim, Jin Goo; Lee, Yong Seuk; Lee, Soo Won; Kim, Young Jae; Kong, Doo Hwan; Ko, Min Soo

    2009-07-01

    This article describes a novel medial meniscal allograft transplantation method that permits easy passage of posterior bone plugs and facilitates bone-to-bone healing. With this method, an anterior bone plug with a long cylindrical shape is prepared, and the posterior bone plug is prepared using only a 2-mm deep, flat bone shell containing cancellous material with 6 baseball Ethibond stitches placed around it. The graft is divided into 3 portions, and boundaries of each are marked. Using a posteromedial portal, the posterior bony bed is prepared directly, and the exact anatomic location is visualized. This modified method facilitates graft passage as well as bone-to-bone healing.

  5. Arthroscopic or conservative treatment of degenerative medial meniscal tears: a prospective randomised trial.

    PubMed

    Herrlin, Sylvia; Hållander, Maria; Wange, Peter; Weidenhielm, Lars; Werner, Suzanne

    2007-04-01

    In this prospective randomised study two treatments after non-traumatic medial meniscal tear diagnosed with radiological examination and magnetic resonance imaging were compared; arthroscopic partial meniscectomy followed by supervised exercise or supervised exercise alone. The aim was to evaluate knee function and physical activity. Ninety patients (mean age 56 years) were evaluated using the Knee Injury and Osteoarthritis Outcome Score, the Lysholm Knee Scoring Scale, the Tegner Activity Scale and a Visual Analogue Scale for knee pain prior to the intervention, after 8 weeks of exercise and after 6 months. According to the outcome scores arthroscopic partial medial meniscectomy combined with exercise did not lead to greater improvement than exercise alone. After the intervention both groups reported decreased knee pain, improved knee function and a high satisfaction (P<0.0001). Forty-one per cent of the patients returned to their pre-injury activity level after 6 months. In conclusion, when evaluated with outcome scores, arthroscopic partial medial meniscectomy followed by supervised exercise was not superior to supervised exercise alone in terms of reduced knee pain, improved knee function and improved quality of life.

  6. Biomechanical evaluation of knee kinematics after anatomic single- and anatomic double-bundle ACL reconstructions with medial meniscal repair.

    PubMed

    Lorbach, Olaf; Kieb, Matthias; Domnick, Christoph; Herbort, Mirco; Weyers, Imke; Raschke, Michael; Engelhardt, Martin

    2015-09-01

    To evaluate knee laxity after anatomic ACL reconstruction with additional suture repair of a medial meniscus tear. 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 (aTTPS) using a robotic/universal force moment sensor testing system. Subsequently, the ACL was resected following the creation of a standardized tear of the medial meniscus, a standard meniscus repair and an ACL reconstruction using an anatomic single-bundle (6) or an anatomic double-bundle technique (6). Knee kinematics were determined following every sub-step. Significant increase of aTT in the ACL-deficient knee was found (p ≤ 0.001) with a further increase in the ACL-deficient knee with additional medial meniscal rupture (p ≤ 0.001). ACL reconstructions significantly decreased aTT compared with the ACL and meniscus-ruptured knee. No significant differences were seen between the intact knee and the ACL-reconstructed knee with additional meniscal repair (p < 0.05). In response to a simulated pivot shift, aTTPS in the intact knee significantly increased in the ACL-deficient knee and meniscus-ruptured knee (p = 0.005). No significant differences in knee kinematics were found between SB as well as DB ACL reconstruction with additional medial meniscal repair compared with the intact knee. Comparison of SB versus DB ACL reconstruction did not reveal any significant differences in a simulated Lachman test or simulated pivot shift test (n.s.). aTT as well as aTTPS significantly increased with ACL deficiency compared with the intact knee; additional medial meniscal rupture further increased aTT. Anatomic ACL reconstruction with medial meniscal repair did not reveal significant differences in knee kinematics compared with the intact knee. Comparison of anatomic SB versus DB ACL reconstruction with additional repair of the medial meniscus did not show

  7. In vivo Cartilage Strain Increases Following Medial Meniscal Tear and Correlates with Synovial Fluid Matrix Metalloproteinase Activity

    PubMed Central

    Carter, Teralyn E.; Taylor, Kevin A.; Spritzer, Charles E.; Utturkar, Gangadhar M.; Taylor, Dean C.; Moorman, Claude T.; Garrett, William E.; Guilak, Farshid; McNulty, Amy L.; DeFrate, Louis E.

    2015-01-01

    Meniscal tears are common injuries, and while partial meniscectomy is a frequent treatment option, general meniscus loss is a risk factor for the development of osteoarthritis. The goal of this study was to measure the in vivo tibiofemoral cartilage contact patterns in patients with meniscus tears in relation to biomarkers of cartilage catabolism in the synovial fluid of these joints. A combination of magnetic resonance imaging and biplanar fluoroscopy was used to determine the in vivo motion and cartilage contact mechanics of the knee. Subjects with isolated medial meniscus tears were analyzed while performing a quasi-static lunge, and the contralateral uninjured knee was used as a control. Synovial fluid was collected from the injured knee and matrix metalloproteinase (MMP) activity, sulfated glycosaminoglycan, cartilage oligomeric matrix protein, prostaglandin E2, and the collagen type II cleavage biomarker C2C were measured. Contact strain in the medial compartment increased significantly in the injured knees compared to contralateral control knees. In the lateral compartment, the contact strain in the injured knee was significantly increased only at the maximum flexion angle (105°). The average cartilage strain at maximum flexion positively correlated with total MMP activity in the synovial fluid. These findings show that meniscal injury leads to loss of normal joint function and increased strain of the articular cartilage, which correlated to elevated total MMP activity in the synovial fluid. The increased strain and total MMP activity may reflect, or potentially contribute to, the early development of osteoarthritis that is observed following meniscal injury. PMID:25801424

  8. Isolation, Characterization, and Multipotent Differentiation of Mesenchymal Stem Cells Derived from Meniscal Debris

    PubMed Central

    Fu, Weili; Xie, Xing; Li, Qi; Chen, Gang; Zhang, Chenghao; Tang, Xin

    2016-01-01

    This study aimed to culture and characterize mesenchymal stem cells derived from meniscal debris. Cells in meniscal debris from patients with meniscal injury were isolated by enzymatic digestion, cultured in vitro to the third passage, and analyzed by light microscopy to observe morphology and growth. Third-passage cultures were also analyzed for immunophenotype and ability to differentiate into osteogenic, adipogenic, and chondrogenic lineages. After 4-5 days in culture, cells showed a long fusiform shape and adhered to the plastic walls. After 10–12 days, cell clusters and colonies were observed. Third-passage cells showed uniform morphology and good proliferation. They expressed CD44, CD90, and CD105 but were negative for CD34 and CD45. Cultures induced to differentiate via osteogenesis became positive for Alizarin Red staining as well as alkaline phosphatase activity. Cultures induced to undergo adipogenesis were positive for Oil Red O staining. Cultures induced to undergo chondrogenesis were positive for staining with Toluidine Blue, Alcian Blue, and type II collagen immunohistochemistry, indicating cartilage-specific matrix. These results indicate that the cells we cultured from meniscal debris are mesenchymal stem cells capable of differentiating along three lineages. These stem cells may be valuable source for meniscal regeneration. PMID:28044083

  9. Magnetic resonance imaging in knee synovitis: clinical utility in differentiating asymptomatic and symptomatic meniscal tears.

    PubMed

    Troupis, John M; Batt, Michael Jethro; Pasricha, Sundeep Singh; Saddik, Daniel

    2015-02-01

    It is well documented that meniscal tears may be found frequently by MRI as an incidental finding in asymptomatic knees. We aim to review the literature regarding the ability of MRI to differentiate between asymptomatic and symptomatic meniscal tears. Ovid MEDLINE, MEDLINE inProcess, Cochrane reviews, Web of Science, Embase and CINAHL were systematically searched. A total of 1251 publications were screened based on their titles, abstracts and full texts, of which 1213 publications were excluded because they did not address the relationship between synovitis and meniscal tears, were case reports or reviews, concerned atypical patient populations or reported surgical research. Of the 38 retained publications, only two reported results specific to perimeniscal synovitis, while 36 discussed less specific but relevant findings. The small number of heterogeneous results describing perimeniscal synovitis precluded meta-analysis. In the symptomatic knee, identification of the likelihood of a meniscal tear contributing to the patient's pain is of significance to the orthopaedic surgeon. In our literature review, we have identified that localised synovitis and displacement of the meniscus are two features that may assist in identifying the subgroup of patients that may benefit from meniscal intervention.

  10. Sensitivities of medial meniscal motion and deformation to material properties of articular cartilage, meniscus and meniscal attachments using design of experiments methods.

    PubMed

    Yao, Jiang; Funkenbusch, Paul D; Snibbe, Jason; Maloney, Mike; Lerner, Amy L

    2006-06-01

    This study investigated the role of the material properties assumed for articular cartilage, meniscus and meniscal attachments on the fit of a finite element model (FEM) to experimental data for meniscal motion and deformation due to an anterior tibial loading of 45 N in the anterior cruciate ligament-deficient knee. Taguchi style L18 orthogonal arrays were used to identify the most significant factors for further examination. A central composite design was then employed to develop a mathematical model for predicting the fit of the FEM to the experimental data as a function of the material properties and to identify the material property selections that optimize the fit. The cartilage was modeled as isotropic elastic material, the meniscus was modeled as transversely isotropic elastic material, and meniscal horn and the peripheral attachments were modeled as noncompressive and nonlinear in tension spring elements. The ability of the FEM to reproduce the experimentally measured meniscal motion and deformation was most strongly dependent on the initial strain of the meniscal horn attachments (epsilon(1H)), the linear modulus of the meniscal peripheral attachments (E(P)) and the ratio of meniscal moduli in the circumferential and transverse directions (E(theta)E(R)). Our study also successfully identified values for these critical material properties (epsilon(1H) = -5%, E(P) = 5.6 MPa, E(theta)E(R) = 20) to minimize the error in the FEM analysis of experimental results. This study illustrates the most important material properties for future experimental studies, and suggests that modeling work of meniscus, while retaining transverse isotropy, should also focus on the potential influence of nonlinear properties and inhomogeneity.

  11. Self-Reduction of Displaced Bucket-Handle Medial Meniscal Tear in a 71-Year-Old Patient: A Case Report.

    PubMed

    Ciminero, Matthew L; Huntley, Samuel R; Ghasem, Alexander D; Pitcher, John D

    2015-12-01

    Bucket-handle meniscal tears are rare in geriatric patients. Displaced bucket-handle meniscal tears are usually treated operatively. Due to the rarity of these tears in elderly patients and conflicting evidence regarding the use of arthroscopy versus conservative treatment, it is valuable to report the clinical presentation, treatment, and outcome of these injuries in elderly patients. We describe a 71-year-old man who presented with an acute, displaced, magnetic resonance imaging (MRI)-confirmed right medial meniscal bucket-handle tear with mild effusion and no signs of degenerative joint disease. On physical examination, the patient was unable to fully extend the right leg due to locking of the knee. At 2-month follow-up, MRI showed mild degenerative changes and an anatomically reduced tear. At 6-month follow-up, the patient reported normal, pain-free knee function, and MRI showed the tear healing in anatomic position with minimal inferior surface changes and no effusion. He returned to his pain-free baseline level of physical activity. Upon review of the English literature, this 71-year-old patient is an exceptional case and one of the oldest patients reported to have sustained a displaced medial meniscal bucket-handle tear treated successfully with nonoperative means. Two reported cases of spontaneously reduced meniscal bucket-handle tears were found in the English literature, although both cases were seen in much younger males and involved the lateral meniscus. This case suggests that in elderly patients with displaced medial meniscus bucket-handle tears that reduce spontaneously, the physician can safely and efficaciously use conservative, nonoperative management to achieve restoration of baseline knee function and anatomic meniscal healing while avoiding the risks of arthroscopic surgery. Surgical intervention for reduction without repair may be an available option, but no literature is present to direct care; however, complete documentation as in the

  12. 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

  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. Oxford phase III meniscal bearing fracture: case report.

    PubMed

    Lim, Hong-Chul; Shon, Won-Yong; Kim, Seung-Ju; Bae, Ji-Hoon

    2014-01-01

    Meniscal bearing fracture is a rare complication of phase III Oxford unicompartmental knee replacement (UKR). We report a case of a meniscal bearing fracture that occurred 7 years after phase III Oxford medial UKR. The meniscal bearing showed uneven delamination of the polyethylene in the thinnest articular surface and an impingement lesion. This lesion initiated a fatigue crack that propagated to cause failure of the meniscal bearing. This is the first report of a meniscal bearing fracture without a posterior marker wire.

  15. Trabecular Bone Structure and Spatial Differences in Articular Cartilage MR Relaxation Times in Individuals with Posterior Horn Medial Meniscal Tears

    PubMed Central

    Kumar, Deepak; Schooler, Joseph; Zuo, Jin; McCulloch, Charles E.; Nardo, Lorenzo; Link, Thomas M.; Li, Xiaojuan; Majumdar, Sharmila

    2012-01-01

    Objective To analyze knee trabecular bone structure and spatial cartilage T1ρ and T2 relaxation times using 3-T MRI in subjects with and without tears of posterior horn of medial meniscus (PHMM). Design 3-T MRI from 59 subjects (> 18 years), were used to evaluate PHMM tears based on modified WORMS scoring; and to calculate apparent trabecular bone - volume over total bone volume fraction (app. BV/TV), number (app. Tb.N), separation (app. Tb.Sp) and thickness (app. Tb.Th) for overall femur/tibia and medial/lateral femur/tibia; and relaxation times for deep and superficial layers of articular cartilage. A repeated measures analysis using GEE was performed to compare trabecular bone and cartilage relaxation time parameters between people with (n = 35) and without (n= 24) PHMM tears, while adjusting for age and knee OA presence. Results Subjects with PHMM tears had lower app. BV./TV and app. Tb.N, and greater app. Tb.Th, and app. Tb.Sp. They also had higher T1ρ times in the deep cartilage layer for lateral tibia and medial femur and higher T2 relaxation times for the deep cartilage layer across all compartments. Conclusions PHMM tears are associated with differences in underlying trabecular bone and deep layer of cartilage. Overload of subchondral bone can lead to its sclerosis and stress shielding of trabecular bone leading to the resorptive changes observed in this study. The results underline the importance of interactions of trabecular bone and cartilage in the pathogenesis of knee OA in people with PHMM tears. PMID:23047010

  16. Nerve growth factor inhibition with tanezumab influences weight-bearing and subsequent cartilage damage in the rat medial meniscal tear model

    PubMed Central

    LaBranche, Timothy P; Bendele, Alison M; Omura, Brian C; Gropp, Kathryn E; Hurst, Susan I; Bagi, Cedo M; Cummings, Thomas R; Grantham, Lonnie E; Shelton, David L; Zorbas, Mark A

    2017-01-01

    Objective To investigate whether the effects of nerve growth factor (NGF) inhibition with tanezumab on rats with medial meniscal tear (MMT) effectively model rapidly progressive osteoarthritis (RPOA) observed in clinical trials. Methods Male Lewis rats underwent MMT surgery and were treated weekly with tanezumab (0.1, 1 or 10 mg/kg), isotype control or vehicle for 7, 14 or 28 days. Gait deficiency was measured to assess weight-bearing on the operated limb. Joint damage was assessed via histopathology. A second arm, delayed onset of treatment (starting 3–8 weeks after MMT surgery) was used to control for analgesia early in the disease process. A third arm, mid-tibial amputation, evaluated the dependency of the model on weight-bearing. Results Gait deficiency in untreated rats was present 3–7 days after MMT surgery, with a return to normal weight-bearing by days 14–28. Prophylactic treatment with tanezumab prevented gait deficiency and resulted in more severe cartilage damage. When onset of treatment with tanezumab was delayed to 3–8 weeks after MMT surgery, there was no increase in cartilage damage. Mid-tibial amputation completely prevented cartilage damage in untreated MMT rats. Conclusions These data suggest that analgesia due to NGF inhibition during the acute injury phase is responsible for increased voluntary weight-bearing and subsequent cartilage damage in the rat MMT model. This model failed to replicate the hypotrophic bone response observed in tanezumab-treated patients with RPOA. PMID:27381034

  17. New observations on meniscal cysts.

    PubMed

    Anderson, Jada Jean; Connor, Gregory F; Helms, Clyde A

    2010-12-01

    The purpose of this study was to determine the incidence of meniscal cysts, assess the frequency of various magnetic resonance (MR) imaging characteristics, and emphasize radiographic observations not commonly reported. A total of 2,095 consecutive knee MR imaging reports from a 22 month period were retrospectively reviewed for the presence of meniscal cysts. Two musculoskeletal radiologists reviewed the cases where cysts were reported. A meniscal cyst was considered present if abnormally increased signal was identified within an enlarged meniscus (i.e., intrameniscal cyst) or if a loculated fluid-intensity lesion with a clear connection to the adjacent meniscus was identified (i.e., parameniscal cyst). Presence or absence of a meniscal tear, intrameniscal and parameniscal signal intensity, patient age, sex, location of meniscal cyst, presence of discoid meniscus, and size of the parameniscal cyst component were recorded. All knee imaging examinations were performed on a 1.5T MR unit. Imaging findings were correlated with arthroscopic reports when available. A total of 167 cases (8.0%) of meniscal cysts were diagnosed in 161 patients. Of the 167 cysts, 69 (41.3%) were located in the lateral meniscus and 98 (58.7%) in the medial meniscus. In 6 patients (3.7%), meniscal cysts were present in both menisci of the same knee. Twelve (7.2%) meniscal cysts were associated with discoid menisci. Ninety-seven (57.8%) meniscal cysts were associated with meniscal tears. Of the total number of meniscal cysts, 104 (62.3%) had a parameniscal cyst. An isolated intrameniscal cyst was present in 63 (37.7%) cases. One hundred (96%) of the parameniscal cyst components were isointense to fluid on T2-weighted FSE images. All cysts exhibited abnormal intrameniscal signal. Only 14 (8.4%) of the intrameniscal components were isointense to fluid on T2-weighted FSE images. The arthroscopic reports of 88 of the 161 (54.7%) patients were available for review and correlation. A tear extending to

  18. Incidence of meniscal injury in cats with cranial cruciate ligament ruptures

    PubMed Central

    Ruthrauff, Cassandra M.; Glerum, Leigh E.; Gottfried, Sharon D.

    2011-01-01

    This retrospective study evaluated the incidence of meniscal injury in cats with cranial cruciate ligament (CCL) ruptures. Medical records for cats diagnosed with CCL ruptures treated by a lateral fabellotibial suture (LFS) were reviewed for signalment, history, physical examination and surgical findings. Ninety-five cats (98 stifles) met the inclusion criteria. The incidence of meniscal injuries in feline CCL deficient stifles was 67%. Isolated medial meniscal injuries were found in 55 stifles (56%), isolated lateral meniscal injuries were found in 5 stifles (5%), and lateral and medial meniscal injuries were found in 6 stifles (6%). There was no correlation between the presence of a meniscal injury and age, breed, sex, weight, duration of lameness, presence of concurrent medial patellar luxation, degree of degenerative joint disease, or presenting side of lameness. Given the high rate of meniscal pathology in cats with CCL ruptures, exploratory surgery for meniscal assessment and concurrent stifle stabilization should be considered in feline patients. PMID:22467966

  19. 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

  20. The Mediolateral Excursion of the Meniscal Bearing during Flexion and Extension of the Knee after Medial Mobile-Bearing Unicompartmental Knee Arthroplasty.

    PubMed

    Lee, Seung-Yup; Bae, Ji-Hoon; Suh, Dong-Won; Kim, Han-Ju; Lim, Hong-Chul

    2017-02-01

    This mediolateral excursion of the bearing during knee motion is supposed to be caused by external rotation of the tibia during knee extension. However, to our knowledge, there is no published clinical evidence supporting these hypotheses. The current study aimed to evaluate the mediolateral excursion of the bearing during flexion-extension motion of the knee after medial unicompartmental knee arthroplasty (UKA). In 52 knees, varus/valgus (F-VarVal) or rotational position (F-Rot) of the femoral component and relative location of the bearing were measured with the standing anteroposterior and modified axial view, respectively. We adopted the modified axial radiographs that are simple to assess the bearing position in the flexed knee. The modified axial view showed excellent inter- and intraobserver agreements. F-Rot in the modified axial view and CT showed a high agreement in terms of validity (r = 0.98; p < 0.0001). On average, the bearing showed more medial position in extension than flexion of the knee. No correlation was found between the femoral component positions (F-VarVal and F-Rot) and mediolateral bearing excursion (p = 0.68 and 0.80, respectively). In conclusion, coronal location of bearing according to flexion-extension of the knee is not influenced by the coronal and axial alignment of the femoral component. With simple radiographic method, more medial position of the bearing according to flexion-extension of the knee. Our method could be used to assess axial rotation of the femoral component and spin-out phenomenon of the bearing following the medial UKA.

  1. Hyperelastic properties of human meniscal attachments.

    PubMed

    Abraham, Adam C; Moyer, John T; Villegas, Diego F; Odegard, Gregory M; Haut Donahue, Tammy L

    2011-02-03

    Meniscal attachments are ligamentous tissues anchoring the menisci to the underlying subchondral bone. Currently little is known about the behavior of meniscal attachments, with only a few studies quantitatively documenting their properties. The objective of this study was to quantify and compare the tensile mechanical properties of human meniscal attachments in the transverse direction, curve fit experimental Cauchy stress-stretch data to evaluate the hyperelastic behavior, and couple these results with previously obtained longitudinal data to generate a more complete constitutive model. Meniscal attachment specimens were tested using a uniaxial tension test with the collagen fibers oriented perpendicular to the loading axis. Tests were run until failure and load-optical displacement data was recorded for each test. The medial posterior attachment was shown to have a significantly greater elastic modulus (6.42±0.78 MPa) and ultimate stress (1.73±0.32 MPa) when compared to the other three attachments. The Mooney-Rivlin material model was selected as the best fit for the transverse data and used in conjunction with the longitudinal data. A novel computational approach to determining the transition point between the toe and linear regions is presented for the hyperelastic stress-stretch curves. Results from piece-wise non-linear longitudinal curve fitting correlate well with previous linear elastic and SEM findings. These data can be used to advance the design of meniscal replacements and improve knee joint finite element models. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. HYPERELASTIC PROPERTIES OF HUMAN MENISCAL ATTACHMENTS

    PubMed Central

    Abraham, Adam C.; Moyer, John T.; Villegas, Diego F.; Odegard, Gregory M.; Donahue, Tammy L. Haut

    2010-01-01

    Meniscal attachments are ligamentous tissues anchoring the menisci to the underlying subchondral bone. Currently little is known about the behavior of meniscal attachments, with only a few studies quantitatively documenting their properties. The objective of this study was to quantify and compare the tensile mechanical properties of human meniscal attachments in the transverse direction, curve fit experimental Cauchy stress-stretch data to evaluate the hyperelastic behavior, and couple those results with previously obtained longitudinal data to generate a more complete constitutive model. Meniscal attachment specimens were tested using a uniaxial tension test with the collagen fibers oriented perpendicular to the loading axis. Tests were run until failure and load-optical displacement data was recorded for each test. The medial posterior attachment was shown to have a significantly greater elastic modulus (5.38±0.77 MPa) and ultimate stress (1.73±0.32 MPa) when compared to the other three attachments. The Mooney-Rivlin material model was selected as the best fit for the transverse data and used in conjunction with the longitudinal data. A novel computational approach to determining the transition point between the toe and linear regions is presented for the hyperelastic stress stretch curves. Results from piece-wise non-linear longitudinal curve fitting correlate well with previous linear elastic and SEM findings. These data can be used to advance the design of meniscal replacements and improve knee joint finite element models. PMID:20980006

  3. Is radiographic measurement of bony landmarks reliable for lateral meniscal sizing?

    PubMed

    Yoon, Jung-Ro; Kim, Taik-Seon; Lim, Hong-Chul; Lim, Hyung-Tae; Yang, Jae-Hyuk

    2011-03-01

    The accuracy of meniscal measurement methods is still in debate. The authors' protocol for radiologic measurements will provide reproducible bony landmarks, and this measurement method of the lateral tibial plateau will correlate with the actual anatomic value. Controlled laboratory study. Twenty-five samples of fresh lateral meniscus with attached proximal tibia were obtained during total knee arthroplasty. Each sample was obtained without damage to the meniscus and bony attachment sites. The inclusion criterion was mild to moderate osteoarthritis in patients with mechanical axis deviation of less than 15°. Knees with lateral compartment osteoarthritic change or injured or degenerated menisci were excluded. For the lateral tibial plateau length measurements, the radiographic beam was angled 10° caudally at neutral rotation, which allowed differentiation of the lateral plateau cortical margins from the medial plateau. The transition points were identified and used for length measurement. The values of length were then compared with the conventional Pollard method and the anatomic values. The width measurement was done according to Pollard's protocol. For each knee, the percentage deviation from the anatomic dimension was recorded. Intraobserver error and interobserver error were calculated. The deviation of the authors' radiographic length measurements from anatomic dimensions was 1.4 ± 1.1 mm. The deviation of Pollard's radiographic length measurements was 4.1 ± 2.0 mm. With respect to accuracy-which represents the frequency of measurements that fall within 10% of measurements-the accuracy of authors' length was 98%, whereas for Pollard's method it was 40%. There was a good correlation between anatomic meniscal dimensions and each radiologic plateau dimensions for lateral meniscal width (R(2) = .790) and the authors' lateral meniscal length (R(2) = .823) and fair correlation for Pollard's lateral meniscal length (R(2) = .660). The reliability of each

  4. Mechanical properties and morphological analysis of the transitional zone between meniscal body and ligamentous meniscal attachments.

    PubMed

    Freutel, M; Scholz, N B; Seitz, A M; Ignatius, A; Dürselen, L

    2015-06-01

    In recent years, an increasing number of studies reporting on meniscal root tears have been published. While the meniscus and its ligamentous meniscal attachments have been studied before, little is known about the transitional zone between these two structures. Therefore, the aim of this study was to mechanically and morphologically characterize the transitional zone between meniscus and its meniscal attachments. Dumbbell-shaped specimens were obtained from the transitional zone between meniscus and its meniscal attachments of 6 knee joints. Samples were divided into tibial and central layers of the anterior lateral (AL), anterior medial (AM), posterior lateral (PL) and posterior medial (PM) transitional region. Testing was performed to obtain the dissipated energy during hysteresis as well as the linear modulus (Elin), the maximum strain (εmax), the maximum engineering stress (σmax,eng) and location of rupture during tensile test to failure. Two additional knee joints were used to investigate morphological differences between meniscus, transitional zone and meniscal attachments in 8µm transverse slices. The central layer of the AL, AM and PL dissipated up to 48% less energy than the tibial layer. Elin was highest in the tibial layer of the PM with 107.4±61.1MPa and lowest in the central layer of the PL with 56.0±20.5MPa. The maximum strain was higher in the central layer than in the tibial layer at the AL, AM, and PL locations. The average σmax,eng was 12.7±9.9MPa over all location and layers. 78% of the samples ruptured during tensile test to failure in the transitional zone. The morphological evaluation showed a smooth transitional zone with a transitional curve which was either linear or bell-shaped. The strength found in the transitional zone was lower than in the meniscus and the meniscal attachments, which corresponds well to clinical findings.

  5. 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.

  6. 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

    2016-01-01

    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.

  7. [Consequences of arthroscopic meniscal resection].

    PubMed

    Faunø, P; Nielsen, A B

    1993-10-18

    The functional and radiological consequences of arthroscopic meniscal resection were assessed in an 8.5 years follow up of 136 patients. Twenty three percent had undergone re-arthroscopy. Function related pain in the operated knee was reported by 44% of the patients. Radiological degenerative changes appeared in significantly more of the operated knees than in the knees not operated. The combination of varus knees and resection of the medial meniscus or valgus knees and lateral resection was associated with significantly more degenerative changes than after resection in knees with normal alignment. Resection of flap tears was associated with more re-operations and more function related knee pain than resection of bucket-handle lesions.

  8. The accuracy of joint line tenderness by physical examination in the diagnosis of meniscal tears.

    PubMed

    Eren, Osman Tuğrul

    2003-10-01

    The purpose of this study was to document the accuracy of joint line tenderness in the diagnosis of meniscal tears. Prospective cohort study. There were 104 male recruits (age range, 18 to 20 years; mean, 19.2 years) with suspected meniscal lesions who underwent arthroscopy. A thorough history and physical examination was performed on each patient by a physician with 4 years' experience on arthroscopic knee surgery. Twenty-six (25%) patients sustained injuries while in the Turkish Army, and 78 patients (75%) sustained injuries before they came to the army. On physical examination, assessment of joint line tenderness at the lateral and medial joint lines was performed with the patient's knee flexed 90 degrees. The accuracy, sensitivity, specificity, and positive and negative predictive values of joint line tenderness for medial and lateral sides were calculated based on arthroscopic findings. In 104 knees, the diagnosis was correct in 71 (68%) and incorrect in 33 (32%) knees. A total of 37 medial meniscal tears and 27 lateral meniscal tears were identified at arthroscopy. Other pathology included 11 anterior cruciate ligament (ACL) tears, 5 medial femoral chondral lesions, 4 chondromalacia patellae, and 1 medial plica. No discernable abnormalities were seen in 21 knees. A preoperative diagnosis of a medial meniscal tear was made in 54 knees and 32 were confirmed at arthroscopy. A lateral meniscus tear was suspected in 27 knees and confirmed in 25. Five medial meniscus and 2 lateral meniscus tears were seen at arthroscopy. These had not been suspected with tenderness over the joint line. The accuracy of the test was lower with the presence of ACL lesions and condromalacia patella. I concluded that joint line tenderness as a test for lateral meniscal tears is accurate (96%), sensitive (89%), and specific (97%). However, for medial meniscal tears, rates are lower.

  9. [Assessment of the relationship between trauma and meniscal lesions].

    PubMed

    Weber, M

    1994-04-01

    Until the 1930s all meniscal lesions were considered to be of traumatic origin. The efforts of Magnus and his pupils led to a more differentiated medicolegal interpretation of wear and tear of the meniscus and classification of at least some types of meniscal lesions as nontraumatic in the sense of accident insurance. This caused controversy, continuing to the present day, as to whether trauma or degeneration is essential for a meniscal tear. This debate can now be closed. Numerous investigations of meniscus pathology have proved that the isolated, essentially traumatic meniscal tear does not exist. Only if the viscoelastic properties of meniscus tissue are changed may indirect force cause a rupture. There is no longer any reason to follow principles for the assessment of meniscus damage differing from those for tendon or intervertebral disc lesions. Only penetrating joint injuries or joint fractures may lead to a direct meniscal lesion (corresponding to penetrating spine trauma or vertebral body fracture with concomitant disc lesion). Separation of the meniscus from its insertion is the analog of discoligamentous spinal trauma. Post-traumatic meniscus degeneration due to joint instability is equivalent to the instability of the motion segment with intervertebral disc degeneration. Isolated meniscal tears and isolated intervertebral disc ruptures cannot be caused by indirect force. The conventional, inconsistently applied criteria to distinguish traumatic and degenerative meniscal lesions are no longer necessary.

  10. A statistically-augmented computational platform for evaluating meniscal function

    PubMed Central

    Guo, Hongqiang; Santner, Thomas J.; Chen, Tony; Wang, Hongsheng; Brial, Caroline; Gilbert, Susannah L.; Koff, Matthew F.; Lerner, Amy L.; Maher, Suzanne A.

    2015-01-01

    Meniscal implants have been developed in an attempt to provide pain relief and prevent pathological degeneration of articular cartilage. However, as yet there has been no systematic and comprehensive analysis of the effects of the meniscal design variables on meniscal function across a wide patient population, and there are no clear design criteria to ensure the functional performance of candidate meniscal implants. Our aim was to develop a statistically-augmented, experimentally-validated, computational platform to assess the effect of meniscal properties and patient variables on knee joint contact mechanics during the activity of walking. Our analysis used Finite Element Models (FEMs) that represented the geometry, kinematics as based on simulated gait and contact mechanics of three laboratory tested human cadaveric knees. The FEMs were subsequently programmed to represent prescribed meniscal variables (circumferential and radial/axial moduli - Ecm, Erm, stiffness of the meniscal attachments - Slpma, Slamp) and patient variables (varus/valgus alignment – VVA, and articular cartilage modulus - Ec). The contact mechanics data generated from the FEM runs were used as training data to a statistical interpolator which estimated joint contact data for untested configurations of input variables. Our data suggested that while Ecm and Erm of a meniscus are critical in determining knee joint mechanics in early and late stance (peak 1 and peak 3 of the gait cycle), for some knees that have greater laxity in the mid-stance phase of gait, the stiffness of the articular cartilage, Ec, can influence force distribution across the tibial plateau. We found that the medial meniscus plays a dominant load-carrying role in the early stance phase and less so in late stance, while the lateral meniscus distributes load throughout gait. Joint contact mechanics in the medial compartment are more sensitive to Ecm than those in the lateral compartment. Finally, throughout stance, varus

  11. A statistically-augmented computational platform for evaluating meniscal function.

    PubMed

    Guo, Hongqiang; Santner, Thomas J; Chen, Tony; Wang, Hongsheng; Brial, Caroline; Gilbert, Susannah L; Koff, Matthew F; Lerner, Amy L; Maher, Suzanne A

    2015-06-01

    Meniscal implants have been developed in an attempt to provide pain relief and prevent pathological degeneration of articular cartilage. However, as yet there has been no systematic and comprehensive analysis of the effects of the meniscal design variables on meniscal function across a wide patient population, and there are no clear design criteria to ensure the functional performance of candidate meniscal implants. Our aim was to develop a statistically-augmented, experimentally-validated, computational platform to assess the effect of meniscal properties and patient variables on knee joint contact mechanics during the activity of walking. Our analysis used Finite Element Models (FEMs) that represented the geometry, kinematics as based on simulated gait and contact mechanics of three laboratory tested human cadaveric knees. The FEMs were subsequently programmed to represent prescribed meniscal variables (circumferential and radial/axial moduli-Ecm, Erm, stiffness of the meniscal attachments-Slpma, Slamp) and patient variables (varus/valgus alignment-VVA, and articular cartilage modulus-Ec). The contact mechanics data generated from the FEM runs were used as training data to a statistical interpolator which estimated joint contact data for untested configurations of input variables. Our data suggested that while Ecm and Erm of a meniscus are critical in determining knee joint mechanics in early and late stance (peak 1 and peak 3 of the gait cycle), for some knees that have greater laxity in the mid-stance phase of gait, the stiffness of the articular cartilage, Ec, can influence force distribution across the tibial plateau. We found that the medial meniscus plays a dominant load-carrying role in the early stance phase and less so in late stance, while the lateral meniscus distributes load throughout gait. Joint contact mechanics in the medial compartment are more sensitive to Ecm than those in the lateral compartment. Finally, throughout stance, varus

  12. Relationship between meniscal integrity and risk factors for cartilage degeneration.

    PubMed

    Arno, Sally; Bell, Christopher P; Xia, Ding; Regatte, Ravinder R; Krasnokutsky, Svetlana; Samuels, Jonathan; Oh, Cheongeun; Abramson, Steven; Walker, Peter S

    2016-08-01

    The purpose of this study was to use MRI to determine if a loss of meniscal intra-substance integrity, as determined by T2* relaxation time, is associated with an increase of Kellgren-Lawrence (KL) grade, and if this was correlated with risk factors for cartilage degeneration, namely meniscal extrusion, contact area and anterior-posterior (AP) displacement. Eleven symptomatic knees with a KL 2 to 4 and 11 control knees with a KL 0 to 1 were studied. A 3 Tesla MRI scanner was used to scan all knees at 15° of flexion. With a 222N compression applied, a 3D SPACE sequence was obtained, followed by a spin echo 3D T2* mapping sequence. Next, an internal tibial torque of 5Nm was added and a second 3D SPACE sequence obtained. The MRI scans were post-processed to evaluate meniscal extrusion, contact area, AP displacement and T2* relaxation time. KL grade was correlated with T2* relaxation time for both the anterior medial meniscus (r=0.79, p<0.001) and the posterior lateral meniscus (r=0.55, p=0.009). In addition, T2* relaxation time was found to be correlated with risk factors for cartilage degeneration. The largest increases in meniscal extrusion and decreases in contact area were noted for those with meniscal tears (KL 3 to 4). All patients with KL 3 to 4 indicated evidence of meniscal tears. This suggests that a loss of meniscal integrity, in the form of intra-substance degeneration, is correlated with risk factors for cartilage degeneration. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Avulsion of both posterior meniscal roots associated with acute rupture of the anterior cruciate ligament.

    PubMed

    Mariani, Pier Paolo; Iannella, Germano; Cerullo, Guglielmo; Giacobbe, Marco

    2015-09-01

    A rare case of acute avulsion of both posterior meniscal roots concomitant with an acute anterior cruciate ligament (ACL) tear in a professional soccer player is described. While avulsion of the lateral meniscal root has been extensively reported in association with ACL injuries, medial root avulsion has never been reported in association with acute ACL. A review of the video documentation of the match accident revealed the exact mechanism of injury was a forceful external rotation of the standing limb.

  14. Meniscal ossification. II. The normal pattern in the tiger knee.

    PubMed

    Ganey, T M; Ogden, J A; Abou-Madi, N; Colville, B; Zdyziarski, J M; Olsen, J H

    1994-04-01

    Examination of knee menisci of Bengal tigers revealed ossicles within the cartilaginous anterior horn of each medial meniscus. This ossification was not evident in the neonatal animal, but was present in animals aged 20 months or older. The ossicle appeared prior to the completion of skeletal maturation at the knee, and was composed of normal remodeling trabecular bone. While most animals had a single, variably sized ossicle, multiple ossicles also occurred. The meniscal cartilage apposed to the femoral articulation exhibited a distinct columnar pattern in the region of the ossicle, in contrast to the non-columnar pattern throughout the bulk of the meniscus, including the ossicle side apposed to the tibial plateau. In this particular large mammalian species medial meniscal ossification appears to be a normal anatomical variation that progressively develops following birth, and may serve as a model for the phylogenetic (developmental) theory of etiology.

  15. Results of arthroscopic meniscal repair

    PubMed Central

    Orlowski, María Belén; Arroquy, Damián; Chahla, Jorge; Guiñazú, Jorge; Bisso, Martín Carboni; Vilaseca, Tomás

    2017-01-01

    Objectives: Currently the arthroscopic treatment of meniscal pathology has become one of the most common procedures in orthopedic practice and although in most cases meniscectomy is done, meniscal sutures are the treatment of choice when a reparable lesion is diagnosed, especially in young patients. It has been reported that the meniscal repair leads to a lower incidence of developing degenerative changes in the long-term when compared with meniscectomy and nonsurgical treatment of meniscal injuries. The aim of this study was to determine the success rate of meniscal repair achieved in our sports medicine practice. Methods: Between 2006 and 2015, 62 meniscal tears in 58 patients with a mean age of 31 years (range 15-58) were repaired. Mean follow-up was 52 months (range 6-120 months). In 16 patients (28%) was associated with arthroscopic ACL reconstruction. The repair techniques used included outside-in sutures, inside-out sutures, all-inside sutures and a combination of techniques. Failure of the repair was defined by the requirement for repeat knee arthroscopy and partial or subtotal meniscectomy. The indication of arthroscopic revision was based on the presence of mechanical symptoms, after the suture. Results: Failure of meniscus repair occurred in four patients (failure rate: 6.45%), one case was associated with ACL reconstruction (failure rate: 6.25%) and 3 had undergone isolated meniscal suture (failure rate: 8%). The average time for the reoperation was 15 months (4-24). We had no intraoperative complications. Conclusion: The reported failure rate of meniscal repair in stable knees varies between 12% and 43%, with reports that demonstrate a clinical success rate of 100%. In this study, we obtained a success rate of 93.5%. These results are slightly higher than those in the literature, which can be attributed to careful selection of patients and the fact that clinical success tends to be better than the assessed arthroscopically. In summary, we consider the

  16. 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

  17. Epidemiology of isolated meniscal injury and its effect on performance in athletes from the National Basketball Association.

    PubMed

    Yeh, Peter C; Starkey, Chad; Lombardo, Stephen; Vitti, Gary; Kharrazi, F Daniel

    2012-03-01

    The current incidence and outcomes of meniscal injury have not been quantified in professional athletes. To describe the incidence, risk, amount of time lost, and effect on performance for isolated meniscal injury in athletes from the National Basketball Association (NBA). Demographic factors predicting the risk of meniscal tears and the effect of injury in return to play were also investigated. Descriptive epidemiology study. A centralized database was queried to identify meniscal injuries occurring in the NBA over 21 seasons. The frequency of injury, time lost, game exposures, and incidence, rate, and risk were calculated. The preinjury and postinjury player efficiency rating (PER) was used to identify changes in player performance. We identified 129 isolated meniscal tears in NBA athletes during a 21-season span. From this number, 77 (59.7%) involved the lateral meniscus and 52 (40.3%) the medial meniscus. Injuries occurred more frequently in games. The lateral meniscus had a statistically significant higher injury rate. Both left and right knees were equally affected. The number of days missed for lateral meniscal tears and medial meniscal tears was 43.8 ± 35.7 days and 40.9 ± 29.7 days, respectively, and was not statistically different. There was a significant inverse relationship between age and rate of lateral meniscal tears, with lateral meniscal tears more likely to occur up to age 30 years; beyond that medial meniscal tears were more common. Players with a body mass index (BMI) greater than 25 had a significantly increased risk of meniscal tears compared with players with a BMI less than 25, specifically with an increased risk of lateral meniscal tears. Twenty-five players (19.4%) did not return to play. For those who did, upon returning to competition, there was no statistical change in PER from their preinjury status, and the mean number of seasons completed was 4.1 ± 3.7 seasons. The lateral meniscus is more frequently torn than the medial meniscus

  18. Bone Plug Versus Suture-Only Fixation of Meniscal Grafts

    PubMed Central

    Wang, Hongsheng; Gee, Albert O.; Hutchinson, Ian D.; Stoner, Kirsten; Warren, Russell F.; Chen, Tony O.; Maher, Suzanne A.

    2014-01-01

    Background Meniscus allograft transplantation (MAT) is primarily undertaken to relieve the symptoms associated with meniscal deficiencies. However, its ability to restore normal knee joint contact mechanics under physiological loads is still unclear. Purpose To quantify the dynamic contact mechanics associated with 2 commonly used fixation techniques in MAT of the medial compartment: transosseous suture fixation via bone plugs and suture-only fixation at the horns. Study Design Controlled laboratory study. Methods Physiological loads to mimic gait were applied across 7 human cadaveric knees on a simulator. A sensor placed on the medial tibial plateau recorded dynamic contact stresses under the following conditions: (1) intact meniscus, (2) MAT using transosseous suture fixation via bone plugs at the anterior and posterior horns, (3) MAT using suture-only fixation, and (4) total medial meniscectomy. A “remove-replace” procedure was performed to place the same autograft for both MAT conditions to minimize the variability in graft size, geometry, and material property and to isolate the effects of the fixation technique. Contact stress, contact area, and weighted center of contact stress (WCoCS) were quantified on the medial plateau throughout the stance phase. Results Knee joint contact mechanics were sensitive to the meniscal condition primarily during the first half of the gait cycle. After meniscectomy, the mean peak contact stress increased from 4.2 ± 1.2 MPa to 6.2 ± 1.0 MPa (P = .04), and the mean contact area decreased from 546 ± 132 mm2 to 192 ± 122 mm2 (P = .01) compared with the intact meniscus during early stance (14% of the gait cycle). After MAT, the mean contact stress significantly decreased with bone plug fixation (5.0 ± 0.7 MPa) but not with suture-only fixation (5.9 ± 0.7 MPa). Both fixation techniques partially restored the contact area, but bone plug fixation restored it closer to the intact condition. The location of WCoCS in the

  19. Time dependent properties of bovine meniscal attachments: stress relaxation and creep.

    PubMed

    Maes, Jason A; Haut Donahue, T L

    2006-01-01

    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 [Chen, M.I., Branch, T.P., et al., 1996. Is it important to secure the horns during lateral meniscal transplantation? A cadaveric study. Arthroscopy 12(2), 174-181; Alhalki, M.M., et al., 1999. How three methods for fixing a medial meniscal autograft affect tibial contact mechanics. American Journal of Sports Medicine 27(3), 320-328; Haut Donahue, T.L., et al., 2003. How the stiffness of meniscal attachments and meniscal material properties affect tibio-femoral contact pressure computed using a validated finite element model of the human knee joint. Journal of Biomechanics 36(1), 19-34]. The complex loading environment in the knee lends itself to different loading environments for each meniscal attachment. We hypothesize that the creep and stress relaxation characteristics of the horn attachments will be different for the anterior versus posterior, and medial versus lateral attachments. To test this hypothesis, the stress relaxation and creep characteristics of the meniscal horn attachments were determined. The stress relaxation properties of load/stress at the end of the test, and the load/stress relaxation rate demonstrated no significant statistical differences between the attachments. Unlike the stress relaxation properties, the creep properties demonstrated some significant differences amongst the attachments. The normalized displacement at the end of the test, normalized creep rate and strain creep rate for the lateral anterior attachment were significantly different than those of the medial posterior attachment (p<0.05). The two anterior attachments had significantly different strains at the end of the test, as well as significantly different creep strain rates (p<0.05). The two attachments of the medial meniscus revealed no significant differences between any of the

  20. Incidence and risk factors associated with meniscal injuries among active-duty US military service members.

    PubMed

    Jones, Jennifer C; Burks, Robert; Owens, Brett D; Sturdivant, Rodney X; Svoboda, Steven J; Cameron, Kenneth L

    2012-01-01

    Few population-based studies have examined the incidence of meniscal injuries, and limited information is available on the influence of patient's demographic and occupational factors. To examine the incidence of meniscal injuries and the influence of demographic and occupational factors among active-duty US service members between 1998 and 2006. Cohort study. Using the International Classification of Diseases (9th revision) codes 836.0 (medial meniscus), 836.1 (lateral meniscus), and 836.2 (meniscus unspecified), we extracted injury data from the Defense Medical Surveillance System to identify all acute meniscal injuries among active-duty military personnel. Active-duty military personnel serving in all branches of military service during the study period. Incidence rate (IR) per 1000 person-years at risk and crude and adjusted rates by strata for age, sex, race, rank, and service. During the study period, 100201 acute meniscal injuries and 12115606 person-years at risk for injury were documented. The overall IR was 8.27 (95% confidence interval [CI] = 8.22, 8.32) per 1000 person-years. Main effects were noted for all demographic and occupational variables (P < .001), indicating that age, sex, race, rank, and service were associated with the incidence of meniscal injuries. Men were almost 20% more likely to experience an acute meniscal injury than were women (incidence rate ratio = 1.18, 95% CI = 1.15, 1.20). The rate of meniscal injury increased with age; those older than 40 years of age experienced injuries more than 4 times as often as those under 20 years of age (incidence rate ratio = 4.25, 95% CI=4.08,4.42). The incidence of meniscal injury was substantially higher in this study than in previously reported studies. Male sex, increasing age, and service in the Army or Marine Corps were factors associated with meniscal injuries.

  1. 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

  2. Meniscal ossicles in large non-domestic cats.

    PubMed

    Walker, Michael; Phalan, David; Jensen, James; Johnson, James; Drew, Mark; Samii, Valerie; Henry, George; McCauley, Jessica

    2002-01-01

    Radiographs of the stifles of 6 species of 34 large, non-domestic cats were reviewed foremost for the presence of meniscal ossicles and then for the presence of the other potential four sesamoids. The animals in the review included 12 lions, 7 tigers, 7 cougars, 3 leopards, 3 bobcats, and 2 jaguars. Fluoroscopy, arthrography, computed tomography, necropsy, and histology were also used to evaluate the stifles of one tiger after euthanasia. Ossicles were found in the region of the cranial horn of the medial meniscus in most of the lions, tigers, leopards, and jaguars. These ossicles were found in half of the cougars but in none of the bobcats. Among the large, non-domestic cats, meniscal ossicles had been reported previously only in Bengal tigers. The lions, tigers, and leopards having meniscal ossicles appeared to have a lateral but often not a medial fabella of the gastrocnemius muscle, an observation previously unreported. Popliteal sesamoids and patellas were present in all the skeletally mature cats.

  3. Internal pressure of human meniscal root attachments during loading

    PubMed Central

    Abraham, Adam C.; Villegas, Diego F.; Kaufman, Kenton R.; Donahue, Tammy L. Haut

    2014-01-01

    This study investigated the internal fluid pressure of human cadaver meniscal root attachments. A pressure micro-sensor was implanted inside each attachment site. Tibiofemoral joints were compressed to 2x body weight at various flexion angles and pressure recorded for 20 minutes. The anterior cruciate ligament (ACL) was then transected and joints retested. Lastly, a longitudinal incision of the lateral posterior horn was made and the joint retested. Ramp pressure was defined as the pressure when 2x body weight was reached, and equilibrium pressure was recorded at the end of the hold period. The medial posterior attachment was subjected to greater ramp pressure than the medial anterior (p=0.002) and greater equilibrium pressure than all other root attachment sites (p<0.001). Flexion angle had a significant effect on pressure as full extension was greatest at ramp (p=0.040). Transection of the ACL decreased ramp pressure in the lateral posterior attachment (p=0.025) and increased equilibrium pressure (p=0.031) in the medial posterior attachment. The results suggest that repair strategies should be developed which reconstruct the medial posterior attachments to be sufficient to withstand large pressures. Furthermore, since meniscal pressure is highest at full extension, this fact should be considered when prescribing rehabilitation following repair of an attachment. PMID:23775981

  4. Cystic hematoma formation following use of a biodegradable arrow for meniscal repair.

    PubMed

    Hechtman, K S; Uribe, J W

    1999-03-01

    This is a case report of a cystic hematoma formation following the use of a biodegradable arrow for repair of a medial meniscus tear. A literature search found no previous report of this complication. Open hematoma debridement and arrow removal were effective in the treatment of this complication following all-inside meniscal repair with a biodegradable arrow.

  5. Value of modern sonography in the assessment of meniscal lesions.

    PubMed

    Wareluk, Pawel; Szopinski, Kazimierz T

    2012-09-01

    The aim of this prospective study was to assess the accuracy of modern ultrasonography in diagnostic imaging of meniscal tears. One hundred and sixty menisci were evaluated in 80 patients (42 females, 38 males, mean age=36.2 years, range=16-70 years). Inclusion criteria for the study were twofold: clinical suspicion of meniscal injury and clinical indication for arthroscopy. Knee examination was performed with the Voluson 730 Expert ultrasound system (General Electric). After sonographic examination, all patients underwent arthroscopic procedures within 1-4 days. The final diagnosis of meniscal tears was taken from surgical reports. The overall sensitivity, specificity, positive predictive value and negative predictive value of sonographic examination in the assessment of meniscal tears amounted to 85.4%, 85.7%, 67.3% and 94.4%, respectively. The statistical parameters were not statistically different in medial and lateral menisci. Age, sex, body mass index (BMI), weight, physical activity, mechanism on injury, and time lapse from injury did not have a statistically significant impact on the usefulness of ultrasonography. The highest sensitivity (>90%) was obtained in medial menisci and in patients with a BMI>25. The highest specificity (>90%) was obtained in lateral menisci, in patients after twisting injuries, in sports injuries, and in recent injuries (time lapse from the injury <1 month). The positive predictive value (PPV) of sonographic examination was higher than 90% only in recent injuries (<1 month), however, the negative predictive value of ultrasound is high, being less than 90% in males with lesions of lateral menisci and in sequelae of sports injuries.

  6. Differential involvement of the medial prefrontal cortex across variants of contextual fear conditioning.

    PubMed

    Heroux, Nicholas A; Robinson-Drummer, Patrese A; Sanders, Hollie R; Rosen, Jeffrey B; Stanton, Mark E

    2017-08-01

    The context preexposure facilitation effect (CPFE) is a contextual fear conditioning paradigm in which learning about the context, acquiring the context-shock association, and retrieving/expressing contextual fear are temporally dissociated into three distinct phases. In contrast, learning about the context and the context-shock association happens concurrently in standard contextual fear conditioning (sCFC). By infusing the GABAA receptor agonist muscimol into medial prefrontal cortex (mPFC) in adolescent Long-Evans rats, the current set of experiments examined the functional role of the mPFC in each phase of the CPFE and sCFC. In the CPFE, the mPFC is necessary for the following: acquisition and/or consolidation of context memory (Experiment 1), reconsolidation of a context memory to include shock (Experiment 2), and expression of contextual fear memory during a retention test (Experiment 3). In contrast to the CPFE, inactivation of the mPFC prior to conditioning in sCFC has no effect on acquisition, consolidation, or retention of a contextual fear memory (Experiment 4). Interestingly, the mPFC is not required for acquiring a context-shock association (measured by post-shock freezing) in the CPFE or sCFC (Experiment 2b and 4). Taken together, these results indicate that the mPFC is differentially recruited across stages of learning and variants of contextual fear conditioning (CPFE versus sCFC). More specifically, separating out learning about the context and the context-shock association necessitates activation of the medial prefrontal cortex during early learning and/or consolidation. © 2017 Heroux et al.; Published by Cold Spring Harbor Laboratory Press.

  7. The medial prefrontal and orbitofrontal cortices differentially regulate dopamine system function.

    PubMed

    Lodge, Daniel J

    2011-05-01

    The prefrontal cortex (PFC) is essential for top-down control over higher-order executive function. In this study we demonstrate that the medial prefrontal cortex (mPFC) and orbitofrontal cortex (OFC) differentially regulate VTA dopamine neuron activity, and furthermore, the pattern of activity in the PFC drastically alters the dopamine neuron response. Thus, although single-pulse activation of the mPFC either excites or inhibits equivalent numbers of dopamine neurons, activation of the OFC induces a primarily inhibitory response. Moreover, activation of the PFC with a pattern that mimics spontaneous burst firing of pyramidal neurons produces a strikingly different response. Specifically, burst-like activation of the mPFC induces a massive increase in dopamine neuron firing, whereas a similar pattern of OFC activation largely inhibits dopamine activity. Taken together, these data demonstrate that the mPFC and OFC differentially regulate dopamine neuron activity, and that the pattern of cortical activation is critical for determining dopamine system output.

  8. A case report of semitendinosus tendon autograft for reconstruction of the meniscal wall supporting a collagen implant

    PubMed Central

    2013-01-01

    Purpose Describe the evolution of the reconstruction of meniscal rim with semitendinosus tendon in a patient with knee pain after a subtotal meniscectomy and absence of meniscal wall. Method 32 years old male with a six-month history of the left knee pain after a subtotal meniscectomy. The MRI indicated a small internal meniscal remainder without posterior horn attachment. Taking this absence as a relative contraindication for implant and meniscal transplantation, the reconstruction of a new meniscal wall with semitendinosus tendon autograft was considered. A collagen meniscal implant was attached to the new wall five months later. Results After two years the patient referred only non specific discomfort with full pain relief in the medial compartment. The MRI revealed integration of implants without significant degenerative changes compared to previous images. Conclusions This staged technique was designed to restore medial meniscus-like biologic tissue in a symptomatic patient following arthroscopic subtotal meniscectomy with a significant loss of the peripheral meniscus rim. Symptomatic improvement was obtained at two years follow-up. PMID:23557091

  9. 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.

  10. A model for the differentiation between grid and conjunctive units in medial entorhinal cortex.

    PubMed

    Si, Bailu; Treves, Alessandro

    2013-12-01

    The multiple layers of medial entorhinal cortex (mEC) contain cells that differ in selectivity, connectivity, and cellular properties. Grid cells in layer II and in the deeper layers express triangular grid patterns in the environment. The firing rate of the conjunctive cells found in layer III and below, on the other hand, show grid-by-head direction tuning. In this study, we model the differentiation between grid and conjunctive cells in a network with self-organized connections. Arranged into distinct "layers", the model grid units and conjunctive units develop, with a similar time course, grid fields resulting from firing rate adaptation and competitive learning. Grid alignment in both layers is delayed with respect to the formation of triangular grids. A common grid orientation among conjunctive units is produced, in the model, by head-direction modulated collateral interactions, while the grids of grid units inherit the same orientation through connections from conjunctive units. Grid units as well as conjunctive units share a similar spacing but show a random distribution of spatial phases. Grid units however carry more spatial information than conjunctive units, thus providing better inputs for the hippocampus to form spatial memories. Copyright © 2013 Wiley Periodicals, Inc.

  11. MR diagnosis of meniscal tears of the knee: analysis of error patterns.

    PubMed

    Van Dyck, Pieter; Gielen, Jan; D'Anvers, Jan; Vanhoenacker, Filip; Dossche, Lieven; Van Gestel, Jozef; Parizel, Paul M

    2007-11-01

    Despite high accuracy of magnetic resonance imaging (MRI) for diagnosing meniscal tears, MR findings do not always agree with surgical findings. We performed a blinded, retrospective study to analyze the nature and frequency of errors in the MR diagnosis of meniscal tears. Medical records of 100 consecutive patients who underwent MR and arthroscopy of the knee at our institution were reviewed. Twelve patients underwent prior meniscal surgery. Twenty-three patients had 27 discrepancies between MR and surgical findings. These were independently reviewed by two additional musculoskeletal radiologists in a double blinded fashion. Original incorrect diagnoses were categorized as either unavoidable, interpretation error or equivocal for meniscal tear. MR accuracy was 88% for the medial and 85% for the lateral meniscus. Of 27 incorrect MR diagnoses, 12 (44%) were unavoidable, 10 (37%) equivocal and 5 (19%) interpretation errors. Of the 67 medial meniscal tears, 12 (18%) were missed. Eight (67%) of these 12 were categorized as equivocal, including three postoperative menisci. Of 30 lateral tears, 12 (40%) were missed, 7 (58%) of which were categorized as unavoidable. Of these 12, 11 (92%) showed fraying of the inner edge, which was shaved at arthroscopy (n = 8) or had stable tear treated conservatively (n = 3). There were three false-positive diagnoses, all occuring in the lateral meniscus, two of which were unavoidable and one interpretation error. Of all missed lateral meniscal tears, most are unavoidable and related to confusion between what represents fraying and what represents a tear. Unavoidable false-positive diagnoses are infrequent and may be related to incomplete arthroscopic evaluation. Subtle or equivocal findings still make MR diagnosis difficult, even for experienced radiologists.

  12. 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

  13. 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.

  14. 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

    2015-12-02

    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.

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

    PubMed Central

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

    2014-01-01

    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

  16. Differential effects of aging and Alzheimer's disease on medial temporal lobe cortical thickness and surface area.

    PubMed

    Dickerson, Bradford C; Feczko, Eric; Augustinack, Jean C; Pacheco, Jenni; Morris, John C; Fischl, Bruce; Buckner, Randy L

    2009-03-01

    The volume of parcellated cortical regions is a composite measure related to both thickness and surface area. It is not clear whether volumetric decreases in medial temporal lobe (MTL) cortical regions in aging and Alzheimer's disease (AD) are due to thinning, loss of surface area, or both, nor is it clear whether aging and AD differ in their effects on these properties. Participants included 28 Younger Normals, 47 Older Normals, and 29 patients with mild AD. T1-weighted MRI data were analyzed using a novel semi-automated protocol (presented in a companion article) to delineate the boundaries of entorhinal (ERC), perirhinal (PRC), and posterior parahippocampal (PPHC) cortical regions and calculate their mean thickness, surface area, and volume. Compared to Younger Normals, Older Normals demonstrated moderately reduced ERC and PPHC volumes, which were due primarily to reduced surface area. In contrast, the expected AD-related reduction in ERC volume was produced by a large reduction in thickness with minimal additional effect (beyond that of aging) on surface area. PRC and PPHC also showed large AD-related reductions in thickness. Of all these MTL morphometric measures, ERC and PRC thinning were the best predictors of poorer episodic memory performance in AD. Although the volumes of MTL cortical regions may decrease with both aging and AD, thickness is relatively preserved in normal aging, while even in its mild clinical stage, AD is associated with a large degree of thinning of MTL cortex. These differential morphometric effects of aging and AD may reflect distinct biologic processes and ultimately may provide insights into the anatomic substrates of change in memory-related functions of MTL cortex.

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

    PubMed

    Sanchez, M A; Dominguez, R

    1995-01-01

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

  18. Effects of suture site or penetration depth on anchor location in all-inside meniscal repair.

    PubMed

    Uchida, Ryohei; Mae, Tatsuo; Hiramatsu, Kunihiko; Iuchi, Ryo; Kinugasa, Kazutaka; Shino, Konsei; Yoshikawa, Hideki; Nakata, Ken

    2016-12-01

    To evaluate the effects of suture site or penetration depth on anchor location in all-inside meniscal repair. Eight fresh-frozen cadaveric knees were evaluated after meniscal repair using eight FasT-Fix360 (FF360) devices (Smith & Nephew Endoscopy, Andover, MA) (16 anchors) for each knee. The penetration depth was 14mm, the distance same from the periphery to insertion point, in four knees (Group A) and that in the remaining four knees (Group B) was 18mm. The anchor location in two groups was evaluated after attentive dissection. Of 32 anchors for the medial meniscus, 94% were on the capsule, including the superficial medial collateral ligament (sMCL) in both groups. For the lateral meniscus, 47% anchors in Group A and 44% anchors in Group B were on the capsule. Total three anchors were over the lateral collateral ligament (LCL), whereas 15 anchors were behind the popliteus tendon (POP). Although all three anchors settled in the subcutaneous fat were in Group B, no significant difference was observed in anchor location between two groups. Secure fixation to thin membranous tissue can be achieved for the medial meniscal repair using FF360, while some were located in/on bunchy LCL or POP in lateral meniscal repair. Only anchors with additional four-millimeter penetration depth were in the subcutaneous fat, although there was no effect of the penetration depth to anchor location. Clinically, for lateral meniscal repair, penetrating toward POP/LCL should be avoided and four-millimeter deeper penetration depth might be a risk for the subcutaneous irritation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Biomechanics of the meniscus-meniscal ligament construct of the knee.

    PubMed

    Masouros, S D; McDermott, I D; Amis, A A; Bull, A M J

    2008-12-01

    The menisci of the knee act primarily to redistribute contact force across the tibio-femoral articulation. This meniscal function is achieved through a combination of the material, geometry and attachments of the menisci. The main ligaments that attach the menisci to the tibia (insertional ligaments, deep medial collateral ligament), the femur (meniscofemoral ligaments, deep medial collateral ligament) and each other (the anterior intermeniscal ligament) are the means by which the contact force between tibia and femur is distributed into hoop stresses in the menisci to reduce contact pressure at the joint. This means that the functional biomechanics of the menisci cannot be considered in isolation and should be considered as the functional biomechanics of the meniscus-meniscal ligament construct. This article presents the current knowledge on the anatomy and functional biomechanics of the meniscus and its associated ligaments. Much is known about the function of the meniscus-meniscal ligament construct; however, there still remain significant gaps in the literature in terms of the properties of the anterior intermeniscal ligament and its function, the properties of the insertional ligaments, and the most appropriate ways to reconstruct meniscal function surgically.

  20. Directionality derived from differential sensitivity to monaural and binaural cues in the cat's medial geniculate body.

    PubMed

    Samson, F K; Barone, P; Irons, W A; Clarey, J C; Poirier, P; Imig, T J

    2000-09-01

    Azimuth tuning of high-frequency neurons in the primary auditory cortex (AI) is known to depend on binaural disparity and monaural spectral (pinna) cues present in broadband noise bursts. Single-unit response patterns differ according to binaural interactions, strength of monaural excitatory input from each ear, and azimuth sensitivity to monaural stimulation. The latter characteristic has been used as a gauge of neural sensitivity to monaural spectral directional cues. Azimuth sensitivity may depend predominantly on binaural disparity cues, exclusively on monaural spectral cues, or on both. The primary goal of this study was to determine whether each cortical response pattern corresponds to a similar pattern in the medial geniculate body (MGB) or whether some patterns are unique to the cortex. Single-unit responses were recorded from the ventral nucleus (Vn) and lateral part of the posterior group of thalamic nuclei (Po), tonotopic subdivisions of the MGB. Responses to free-field presentation of noise bursts that varied in azimuth and sound pressure level were obtained using methods identical to those used previously in field AI. Many units were azimuth sensitive, i.e., they responded well at some azimuths, and poorly, if at all, at others. These were studied further by obtaining responses to monaural noise stimulation, approximated by reversible plugging of one ear. Monaural directional (MD) cells were sensitive to the azimuth of monaural noise stimulation, whereas binaural directional (BD) cells were either insensitive to its azimuth or monaurally unresponsive. Thus BD and MD cells show differential sensitivity to monaural spectral cues. Monaural azimuth sensitivity could not be used to interpret the spectral sensitivity of predominantly binaural cells that exhibited strong binaural facilitation because they were either unresponsive or poorly responsive to monaural stimulation. The available evidence suggests that some such cells are sensitive to spectral cues

  1. Comparative Study of Collagen versus Synthetic-Based Meniscal Scaffolds in Treating Meniscal Deficiency in Young Active Population

    PubMed Central

    Bulgheroni, Erica; Grassi, Alberto; Campagnolo, Monica; Bulgheroni, Paolo; Mudhigere, Abhishek; Gobbi, Alberto

    2016-01-01

    Purpose: The aim of this study was to compare the effectiveness of 2 different meniscal scaffolds in treating patients with irreparable partial medial meniscal tear and patients complaining of pain in the medial compartment of the knee due to a previous partial medial meniscectomy. Based on previous studies, we hypothesized that both the scaffolds are effective in improving clinical outcomes in these patient populations. Material and Methods: Twenty-eight patients underwent collagen-based medial meniscus implantation (CMI-Menaflex) and 25 with a second-generation scaffold (Actifit). All patients were assessed with Lysholm, Tegner scale, and MRI evaluation—preoperatively, at 6 months, at 12 moths, and followed-up for a minimum of 2 years. Second look arthroscopy and concomitant biopsy were performed in 7 and 12 patients of CMI and Actifit groups, respectively. Results: The CMI group at final follow-up showed improvement in Lysholm score from 58.4 ± 17.3 to 94.5 ± 6.0, while the Actifit group showed improvement from 67.0 ± 15.7 to 90.3 ± 13.1; the improvement was statistically significant in both the groups but intergroup difference was not statistically significant (P = 0.1061). Tegner Activity Scale score improved in both the groups, but intergroup difference was not statistically significant (P = 0.5918). MRI evaluation showed in situ scaffold and no progression of degenerative arthritis in both the groups at final follow-up. Histological evaluation showed more fibrous tissue with blood vessels in the CMI group and the Actift group showed avascular cartilaginous features. Conclusion: Both the scaffolds are effective in improving patients’ symptoms and joint function at short-term follow-up. PMID:26958315

  2. Incidence and Risk Factors Associated with Meniscal Injuries Among Active-Duty US Military Service Members

    PubMed Central

    Jones, Jennifer C.; Burks, Robert; Owens, Brett D.; Sturdivant, Rodney X.; Svoboda, Steven J.; Cameron, Kenneth L.

    2012-01-01

    Context: Few population-based studies have examined the incidence of meniscal injuries, and limited information is available on the influence of patient's demographic and occupational factors. Objective: To examine the incidence of meniscal injuries and the influence of demographic and occupational factors among active-duty US service members between 1998 and 2006. Design: Cohort study. Setting: Using the International Classification of Diseases (9th revision) codes 836.0 (medial meniscus), 836.1 (lateral meniscus), and 836.2 (meniscus unspecified), we extracted injury data from the Defense Medical Surveillance System to identify all acute meniscal injuries among active-duty military personnel. Patients or Other Participants: Active-duty military personnel serving in all branches of military service during the study period. Main Outcome Measure(s): Incidence rate (IR) per 1000 person-years at risk and crude and adjusted rates by strata for age, sex, race, rank, and service. Results: During the study period, 100201 acute meniscal injuries and 12115606 person-years at risk for injury were documented. The overall IR was 8.27 (95% confidence interval [CI] = 8.22, 8.32) per 1000 person-years. Main effects were noted for all demographic and occupational variables (P< .001), indicating that age, sex, race, rank, and service were associated with the incidence of meniscal injuries. Men were almost 20% more likely to experience an acute meniscal injury than were women (incidence rate ratio = 1.18, 95% CI = 1.15, 1.20). The rate of meniscal injury increased with age; those older than 40 years of age experienced injuries more than 4 times as often as those under 20 years of age (incidence rate ratio = 4.25,95% CI = 4.08, 4.42). Conclusions: The incidence of meniscal injury was sub-stantially higher in this study than in previously reported studies. Male sex, increasing age, and service in the Army or Marine Corps were factors associated with meniscal injuries. PMID:22488232

  3. Cartilage morphology at 2-3 years following anterior cruciate ligament reconstruction with or without concomitant meniscal pathology.

    PubMed

    Wang, Xinyang; Wang, Yuanyuan; Bennell, Kim L; Wrigley, Tim V; Cicuttini, Flavia M; Fortin, Karine; Saxby, David J; Van Ginckel, Ans; Dempsey, Alasdair R; Grigg, Nicole; Vertullo, Christopher; Feller, Julian A; Whitehead, Tim; Lloyd, David G; Bryant, Adam L

    2017-02-01

    To examine differences in cartilage morphology between young adults 2-3 years post-anterior cruciate ligament reconstruction (ACLR), with or without meniscal pathology, and control participants. Knee MRI was performed on 130 participants aged 18-40 years (62 with isolated ACLR, 38 with combined ACLR and meniscal pathology, and 30 healthy controls). Cartilage defects, cartilage volume and bone marrow lesions (BMLs) were assessed from MRI using validated methods. Cartilage defects were more prevalent in the isolated ACLR (69 %) and combined group (84 %) than in controls (10 %, P < 0.001). Furthermore, the combined group showed higher prevalence of cartilage defects on medial femoral condyle (OR 4.7, 95 % CI 1.3-16.6) and patella (OR 7.8, 95 % CI 1.5-40.7) than the isolated ACLR group. Cartilage volume was lower in both ACLR groups compared with controls (medial tibia, lateral tibia and patella, P < 0.05), whilst prevalence of BMLs was higher on lateral tibia (P < 0.001), with no significant differences between the two ACLR groups for either measure. Cartilage morphology was worse in ACLR patients compared with healthy controls. ACLR patients with associated meniscal pathology have a higher prevalence of cartilage defects than ACLR patients without meniscal pathology. The findings suggest that concomitant meniscal pathology may lead to a greater risk of future OA than isolated ACLR. III.

  4. High meniscal slope angle as a risk factor for meniscal allograft extrusion.

    PubMed

    Łuczkiewicz, P; Daszkiewicz, K; Chróścielewski, J; Witkowski, W; Kuik, L

    2017-04-01

    A meniscal graft extrusion is still an unresolved problem that affects most patients after a meniscal transplantation. Despite the advances in surgical techniques, together with the improved methods for a meniscal allograft sizing, success is only observed in up to 75% of patients after they experience a meniscal allograft transplantation. Because a meniscal extrusion is associated with a cartilage deterioration and the progression of osteoarthritis there is a great interest in how to prevent this phenomenon. The crucial factor for the minimisation of a meniscal allograft extrusion is by perfectly matching the implant. Most methods for a meniscal allograft sizing only focus on assessing the length and the width of the meniscus. Even though there is some evidence that there is a relationship between the shape of the meniscus in a cross-sectional plane and the meniscal extrusion, any of the planning methods do not take this factor into consideration. Although there is a large variability of meniscus shapes in cross-section, we hypothesise that by taking the meniscal slope into account during surgical planning, as well as performing the correct adjustments of this particular parameter, we can diminish the risk of a meniscal allograft extrusion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Incidence and Characteristics of Meniscal Injuries in Cadets at a Military School, 2013-2015.

    PubMed

    Ma, Ji Zheng; Cui, Shu Fang; Hu, Fei; Lu, Qiu Ju; Li, Wei

    2016-11-01

    Meniscal injury is common among military service members.  To examine the incidence and characteristics of meniscal injuries in cadets at a single military institution between 2013 and 2015.  Cohort study.  Meniscal-injury data were collected at the Center of Rehabilitation Training, the People's Liberation Army University of Science and Technology.  A total of 2479 cadets participating in physical activities between 2013 and 2015.  Injury rates, injury proportions by body mass index, risk ratios (RRs), and injury proportion ratios were reported with 95% confidence intervals (CIs).  The overall incidence rate was 10.08 (95% CI = 6.84, 14.84) per 1000 person-years. A multiple-comparisons test revealed differences in the relative injury rate in overweight or obese cadets versus normal-weight cadets and underweight cadets (χ(2) = 8.98, P = .01). No differences were found between injured normal-weight cadets and underweight cadets (P = .66, RR = 1.39, 95% CI = 0.32, 6.06) or between injured overweight or obese cadets and injured underweight cadets (P = .24, RR = 0.42, 95% CI = 0.09, 1.91). The absolute injury rate was higher for overweight and obese cadets compared with normal-weight cadets (P < .01, RR = 0.30, 95% CI = 0.13, 0.69). The overall proportional distribution for patterns of injury was 2:1 (medial to lateral) for meniscal injuries. Grade 2 injuries were the most common.  The high frequency and level of severity of meniscal injuries may negatively affect the readiness and health of cadets. High body mass index was a risk factor for meniscal injury.

  6. [Meniscal repair in patients with chronic lesions].

    PubMed

    Ponce de León, José Clemente Ibarra; Sierra Suárez, Luis; Almazán Díaz, Arturo; Cruz López, Francisco; Pérez Jiménez, Francisco Xavier; Encalada Díaz, Iván; León Hernández, Saúl Renán; Angulo Gutiérrez, Maritza

    2008-01-01

    To analyze the subjective and objective outcome of arthroscopic meniscal repair in patients with chronic meniscal lesions. A group of patients that underwent arthroscopic meniscal repair of chronic tears with a minimum follow-up of six months was retrospectively evaluated. Physical examination oriented at finding persistent meniscal lesions was performed. IKDC, Lysholm and Tegner scores were applied, and a control magnetic resonance imaging (MRI) was performed. Twenty seven menisci in 25 patients were repaired. There were 21 male and 4 female patients with a mean age of 29.6 +/- 8.2 years (20-45). Mean time from lesion to surgery was 25.24 +/- 26 months (6-120). 27. There was significant improvement in all parameters evaluated in 21 patients. Four patients were found to have signs and symptoms of persistent meniscal tears. Abnormal increased signal intensity in the repaired menisci was observed by MRI in all patients, not correlating with clinical findings. Short-term success rate of 85% was obtained with arthroscopic repair of chronic meniscal lesions in this study, which supports the fact that a long period of time before surgery does not necessarily lead to failure. It is valid to perform a meniscal repair in patients with chronic tears as long as the proper surgical technique and an adequate rehabilitation protocol are used.

  7. Percutaneous Partial Medial Collateral Ligament Release (PPMCLR) Does Not Result in Residual Medial Collateral Laxity (MCL)

    PubMed Central

    Hinton, M. Alan

    2015-01-01

    Objectives: The intra-articular posterior medial knee can be difficult to approach during arthroscopy. This is especially true for medial meniscal tears, medial meniscal repairs or medial meniscal transplantation. Various methods and instruments have been proposed to help with this approach. PPMCLR is one of these methods. This study found that this is a safe technique and does not result in measurable laxity of the MCL. Methods: 50 consecutive patients took part in the study. The patients were then randomized into a control or partial percutaneous release group (25 in each group). Prior to arthroscopy each patient had standardized 30 degree valgus stress radiograph performed. The MCL was stressed with the Telos Stress Device GA/III at 30 degrees of flexion; utilizing 150 Newton's of stress. The stress radiographs were measured independently for the maximal separation at the medial compartment. At six weeks the stress radiographs were repeated and the results again recorded. The postoperative care for each group was the same. Results: The results were then statistically evaluated using the, finding no radiographic evidence of residual laxity P<.005. There was also no difference in the control and PPMCLR group p<.0005. No patient complained of residual laxity. Patient follow up will be discussed. Conclusion: PPMCLR is an effective and safe method to reach the intra-articular posterior aspect of the knee during arthroscopy. PPMCLR does not result in measurable laxity of the MCL.

  8. Diagnosis and Management of Meniscal Injury.

    PubMed

    Babu, Jacob; Shalvoy, Robert M; Behrens, Steve B

    2016-10-04

    Meniscal injury is a common cause for presentation to the emergency department or primary care physician's office. Meniscal injuries can be the result of a forceful, twisting event in a young athlete's knee or it can insidiously present in the older patient. Many patients with meniscal pathology appropriately undergo conservative management with a primary care physician while some may need referral to an orthopedist for operative intervention. Arthroscopic surgery to address the menisci is the most frequently performed procedure on the knee and one of the most regularly performed surgeries in orthopedic surgery.1 The purpose of this paper is to help elucidate the diagnosis and management of meniscal pathology resulting in knee pain. [Full article available at http://rimed.org/rimedicaljournal-2016-10.asp].

  9. Meta-Analytic Connectivity Modeling Reveals Differential Functional Connectivity of the Medial and Lateral Orbitofrontal Cortex

    PubMed Central

    Zald, David H.; McHugo, Maureen; Ray, Kimberly L.; Glahn, David C.; Eickhoff, Simon B.; Laird, Angela R.

    2014-01-01

    The orbitofrontal cortex (OFC) is implicated in a broad range of behaviors and neuropsychiatric disorders. Anatomical tracing studies in nonhuman primates reveal differences in connectivity across subregions of the OFC, but data on the connectivity of the human OFC remain limited. We applied meta-analytic connectivity modeling in order to examine which brain regions are most frequently coactivated with the medial and lateral portions of the OFC in published functional neuroimaging studies. The analysis revealed a clear divergence in the pattern of connectivity for the medial OFC (mOFC) and lateral OFC (lOFC) regions. The lOFC showed coactivations with a network of prefrontal regions and areas involved in cognitive functions including language and memory. In contrast, the mOFC showed connectivity with default mode, autonomic, and limbic regions. Convergent patterns of coactivations were observed in the amygdala, hippocampus, striatum, and thalamus. A small number of regions showed connectivity specific to the anterior or posterior sectors of the OFC. Task domains involving memory, semantic processing, face processing, and reward were additionally analyzed in order to identify the different patterns of OFC functional connectivity associated with specific cognitive and affective processes. These data provide a framework for understanding the human OFC's position within widespread functional networks. PMID:23042731

  10. 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

  11. Chondroprotective effects of a polycarbonate-urethane meniscal implant: histopathological results in a sheep model.

    PubMed

    Zur, Gal; Linder-Ganz, Eran; Elsner, Jonathan J; Shani, Jonathan; Brenner, Ori; Agar, Gabriel; Hershman, Elliott B; Arnoczky, Steven P; Guilak, Farshid; Shterling, Avi

    2011-02-01

    injury or loss of the meniscus generally leads to degenerative osteoarthritic changes in the knee joint. However, few surgical options exist for meniscal replacement. The goal of this study was to examine the ability of a non-degradable, anatomically shaped artificial meniscal implant, composed of Kevlar-reinforced polycarbonate-urethane (PCU), to prevent progressive cartilage degeneration following complete meniscectomy. the artificial meniscus was implanted in the knees of mature female sheep following total medial meniscectomy, and the animals were killed at 3- and 6-months post-surgery. Macroscopic analysis and semi-quantitative histological analysis were performed on the cartilage of the operated knee and unoperated contralateral control joint. the PCU implants remained well secured throughout the experimental period and showed no signs of wear or changes in structural or material properties. Histological analysis showed relatively mild cartilage degeneration that was dominated by loss of proteoglycan content and cartilage structure. However, the total osteoarthritis score did not significantly differ between the control and operated knees, and there were no differences in the severity of degenerative changes between 3 and 6 months post-surgery. current findings provide preliminary evidence for the ability of an artificial PCU meniscal implant to delay or prevent osteoarthritic changes in knee joint following complete medial meniscectomy.

  12. Arthroscopic meniscal allograft transplantation without bone plugs.

    PubMed

    Alentorn-Geli, Eduard; Seijas Vázquez, Roberto; García Balletbó, Montserrat; Álvarez Díaz, Pedro; Steinbacher, Gilbert; Cuscó Segarra, Xavier; Rius Vilarrubia, Marta; Cugat Bertomeu, Ramón

    2011-02-01

    Partial or total meniscectomy are common procedures performed at Orthopedic Surgery departments. Despite providing a great relief of pain, it has been related to early onset knee osteoarthritis. Meniscal allograft transplantation has been proposed as an alternative to meniscectomy. The purposes of this study were to describe an arthroscopic meniscal allograft transplantation without bone plugs technique and to report the preliminary results. All meniscal allograft transplantations performed between 2001 and 2006 were approached for eligibility, and a total of 35 patients (involving 37 menisci) were finally engaged in the study. Patients were excluded if they had ipsilateral knee ligament reconstruction or cartilage repair surgery before meniscal transplantation or other knee surgeries after the meniscal transplantation. Scores on Lysholm, Subjective IKDC Form, and Visual Analogue Scale (VAS) scale for pain were obtained at a mean follow-up of 38.6 months and compared to pre-operative data. Data on chondral lesions were obtained during the arthroscopic procedure and through imaging (radiographs and MRI) studies pre-operatively. Two graft failures out of 59 transplants (3.4%) were found. Daily life accidents were responsible for all graft failures. Significant improvements for Lysholm, Subjective IKDC Form, and VAS for pain scores following the meniscal allograft transplantation were found (P < 0.0001). Controlling for chondral lesion, there was no significant interactions for Lysholm (n.s.), Subjective IKDC Form (n.s.), and VAS for pain scores (n.s.). This study demonstrated that an arthroscopic meniscal allograft transplantation without bone plugs improved knee function and symptoms after a total meniscectomy. Improvements were observed independently of the degree of chondral lesion.

  13. 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.

  14. The contribution of 3D quantitative meniscal and cartilage measures to variation in normal radiographic joint space width-Data from the Osteoarthritis Initiative healthy reference cohort.

    PubMed

    Roth, Melanie; Wirth, Wolfgang; Emmanuel, Katja; Culvenor, Adam G; Eckstein, Felix

    2017-02-01

    To explore to what extent three-dimensional measures of the meniscus and femorotibial cartilage explain the variation in medial and lateral femorotibial radiographic joint space width (JSW), in healthy men and women. The right knees of 87 Osteoarthritis Initiative healthy reference participants (no symptoms, radiographic signs or risk factors of osteoarthritis; 37 men, 50 women; age 55.0±7.6; BMI 24.4±3.1) were assessed. Quantitative measures of subregional femorotibial cartilage thickness and meniscal position and morphology were computed from segmented magnetic resonance images. Minimal and medial/lateral fixed-location JSW were determined from fixed-flexion radiographs. Correlation and regression analyses were used to explore the contribution of demographic, cartilage and meniscal parameters to JSW in healthy subjects. The correlation with (medial) minimal JSW was somewhat stronger for cartilage thickness (0.54≤r≤0.67) than for meniscal (-0.31≤r≤0.50) or demographic measures (-0.15≤r≤0.48), in particular in men. In women, in contrast, the strength of the correlations of cartilage thickness and meniscal measures with minimal JSW were in the same range. Fixed-location JSW measures showed stronger correlations with cartilage thickness (r≥0.68 medially; r≥0.59 laterally) than with meniscal measures (r≤|0.32| medially; r≤|0.32| laterally). Stepwise regression models revealed that meniscal measures added significant independent information to the total variance explained in minimal JSW (adjusted multiple r(2)=58%) but not in medial or lateral fixed-location JSW (r(2)=60/51%, respectively). In healthy subjects, minimal JSW was observed to reflect a combination of cartilage and meniscal measures, particularly in women. Fixed-location JSW, in contrast, was found to be dominated by variance in cartilage thickness in both men and women, with somewhat higher correlations between cartilage and JSW in the medial than lateral femorotibial compartment. The

  15. 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.

  16. Meniscal extrusion promotes knee osteoarthritis structural progression: protective effect of strontium ranelate treatment in a phase III clinical trial.

    PubMed

    Roubille, Camille; Martel-Pelletier, Johanne; Raynauld, Jean-Pierre; Abram, François; Dorais, Marc; Delorme, Philippe; Pelletier, Jean-Pierre

    2015-03-23

    To evaluate the impact of meniscal extrusion (Ext) on knee osteoarthritis (OA) structural progression and on response to strontium ranelate (SrRan) treatment at 36 months in patients with (+) or without (-) Ext, in association (+) or not (-) with bone marrow lesions (BML) in the medial compartment using X-rays (JSW) and qMRI. Patients from the qMRI substudy of the SEKOIA trial (SrRan 1 g/day, n = 113; SrRan 2 g/day, n = 105; placebo, n = 112) were stratified based on whether meniscal extrusion and/or BML were present or not in the medial compartment. In the placebo group, Ext+ patients (n = 26) had more JSW loss (p = 0.002) and cartilage volume loss in the global knee (p = 0.034) and plateau (p = 0.005), and medial compartment (p = 0.0005) than Ext- patients (n = 86). Ext-BML+ patients (n = 18) demonstrated more JSW loss (p = 0.003) and cartilage volume loss in the global (p = 0.020) and medial femur (p = 0.055) than Ext-BML- (n = 68). Compared to Ext+ BML- (n = 14), Ext+ BML+ patients (n = 12) had more cartilage volume loss in the global femur (p = 0.028), with no change in JSW. The JSW loss (p = 0.0004) and cartilage volume loss (global knee, p = 0.033, medial compartment, p = 0.0005) were greater when Ext and BML were simultaneously present in the medial compartment. SrRan 2 g/day treatment demonstrated a reduction in OA knee structural progression with qMRI, but not with JSW, in which less cartilage volume loss was found in the plateaus (p = 0.007) in Ext+ patients (n = 15), and in the medial plateau (p = 0.046) in patients in whom both Ext and BML were co-localized. The findings of this study are novel and could have an impact on future strategies regarding clinical trials. Indeed, data first argue for a combined, cumulative effect of meniscal extrusion and bone marrow lesions on cartilage loss and, secondly, they showed that SrRan may have protective

  17. Differential Expression and Function of Nicotinic Acetylcholine Receptors in Subdivisions of Medial Habenula

    PubMed Central

    Shih, Pei-Yu; Engle, Staci E.; Oh, Gyeon; Deshpande, Purnima; Puskar, Nyssa L.; Lester, Henry A.

    2014-01-01

    Neuronal nAChRs in the medial habenula (MHb) to the interpeduncular nucleus (IPN) pathway are key mediators of nicotine's aversive properties. In this paper, we report new details regarding nAChR anatomical localization and function in MHb and IPN. A new group of knock-in mice were created that each expresses a single nAChR subunit fused to GFP, allowing high-resolution mapping. We find that α3 and β4 nAChR subunit levels are strong throughout the ventral MHb (MHbV). In contrast, α6, β2, β3, and α4 subunits are selectively found in some, but not all, areas of MHbV. All subunits were found in both ChAT-positive and ChAT-negative cells in MHbV. Next, we examined functional properties of neurons in the lateral and central part of MHbV (MHbVL and MHbVC) using brain slice patch-clamp recordings. MHbVL neurons were more excitable than MHbVC neurons, and they also responded more strongly to puffs of nicotine. In addition, we studied firing responses of MHbVL and MHbVC neurons in response to bath-applied nicotine. Cells in MHbVL, but not those in MHbVC, increased their firing substantially in response to 1 μm nicotine. Additionally, MHbVL neurons from mice that underwent withdrawal from chronic nicotine were less responsive to nicotine application compared with mice withdrawn from chronic saline. Last, we characterized rostral and dorsomedial IPN neurons that receive input from MHbVL axons. Together, our data provide new details regarding neurophysiology and nAChR localization and function in cells within the MHbV. PMID:25031416

  18. Epitrochlear cat scratch disease: unique imaging features allowing differentiation from other soft tissue masses of the medial arm.

    PubMed

    Bernard, Stephanie A; Walker, Eric A; Carroll, John F; Klassen-Fischer, Mary; Murphey, Mark D

    2016-09-01

    Evaluate anatomic and imaging features of epitrochlear regional adenopathy secondary to cat scratch disease (CSD) to assist differentiation of CSD from other soft tissue masses at the elbow. Retrospective review of 24 confirmed cases of CSD. Patient demographics, clinical presentation and radiographic (R; n = 10), CT (n = 3), ultrasound (US; n = 5), and MR (n = 21) images were reviewed. Lesion location, size, number of masses, and intrinsic characteristics on R/CT/US/MR and presence of soft tissue inflammatory changes or adjacent bone or joint involvement were established through the consensus interpretation by four musculoskeletal radiologists. The average patient age was 18.6 years. Mass location was anterior and superficial to the medial intermuscular septum (100 %) with the masses posterior or posteromedial to the basilic vein (92 %). Three or fewer lymph nodes were involved in 92 %. Masses were noncalcified with adjacent inflammatory change (R = 90 %, CT = 100 %). US showed hypoechoic soft tissue echogenicity masses with defined to minimally irregular margins (80 %) and preserved central hilar hypervascularity on Doppler (100 % of cases). On MR, masses were T1 isointense (62 %), T2 isointense (54 %), intermediate signal on T2 images with fat suppression (55 %), and had perilesional inflammatory changes (95 %), perilesional fluid collections (38 %), adjacent muscle edema (81 %), hyperintense cental hilar vascular enhancement (65 %) and occasional preserved central hilar fat (14 %). Cat scratch disease is suggested by the characteristic location of a medial epitrochlear mass superficial to the brachial fascia and posterior to the basilic vein with surrounding inflammatory changes and preservation of hilar vascular architecture, hilar enhancement and occasional hilar fat.

  19. Calcium deposition in osteoarthritic meniscus and meniscal cell culture.

    PubMed

    Sun, Yubo; Mauerhan, David R; Honeycutt, Patrick R; Kneisl, Jeffrey S; Norton, H James; Zinchenko, Natalia; Hanley, Edward N; Gruber, Helen E

    2010-01-01

    Calcium crystals exist in the knee joint fluid of up to 65% of osteoarthritis (OA) patients and the presence of these calcium crystals correlates with the radiographic evidence of hyaline cartilaginous degeneration. This study sought to examine calcium deposition in OA meniscus and to investigate OA meniscal cell-mediated calcium deposition. The hypothesis was that OA meniscal cells may play a role in pathological meniscal calcification. Studies were approved by our human subjects Institutional Review Board. Menisci were collected during joint replacement surgeries for OA patients and during limb amputation surgeries for osteosarcoma patients. Calcium deposits in menisci were examined by alizarin red staining. Expression of genes involved in biomineralization in OA meniscal cells was examined by microarray and real-time RT-PCR. Cell-mediated calcium deposition in monolayer culture of meniscal cells was examined using an ATP-induced (45)calcium deposition assay. Calcium depositions were detected in OA menisci but not in normal menisci. The expression of several genes involved in biomineralization including ENPP1 and ANKH was upregulated in OA meniscal cells. Consistently, ATP-induced calcium deposition in the monolayer culture of OA meniscal cells was much higher than that in the monolayer culture of control meniscal cells. Calcium deposition is common in OA menisci. OA meniscal cells calcify more readily than normal meniscal cells. Pathological meniscal calcification, which may alter the biomechanical properties of the knee meniscus, is potentially an important contributory factor to OA.

  20. Calcium deposition in osteoarthritic meniscus and meniscal cell culture

    PubMed Central

    2010-01-01

    Introduction Calcium crystals exist in the knee joint fluid of up to 65% of osteoarthritis (OA) patients and the presence of these calcium crystals correlates with the radiographic evidence of hyaline cartilaginous degeneration. This study sought to examine calcium deposition in OA meniscus and to investigate OA meniscal cell-mediated calcium deposition. The hypothesis was that OA meniscal cells may play a role in pathological meniscal calcification. Methods Studies were approved by our human subjects Institutional Review Board. Menisci were collected during joint replacement surgeries for OA patients and during limb amputation surgeries for osteosarcoma patients. Calcium deposits in menisci were examined by alizarin red staining. Expression of genes involved in biomineralization in OA meniscal cells was examined by microarray and real-time RT-PCR. Cell-mediated calcium deposition in monolayer culture of meniscal cells was examined using an ATP-induced 45calcium deposition assay. Results Calcium depositions were detected in OA menisci but not in normal menisci. The expression of several genes involved in biomineralization including ENPP1 and ANKH was upregulated in OA meniscal cells. Consistently, ATP-induced calcium deposition in the monolayer culture of OA meniscal cells was much higher than that in the monolayer culture of control meniscal cells. Conclusions Calcium deposition is common in OA menisci. OA meniscal cells calcify more readily than normal meniscal cells. Pathological meniscal calcification, which may alter the biomechanical properties of the knee meniscus, is potentially an important contributory factor to OA. PMID:20353559

  1. 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

  2. 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.

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

    PubMed

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

    2016-05-01

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

  4. 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

  5. The infralimbic and prelimbic medial prefrontal cortices have differential functions in the expression of anxiety-like behaviors in mice.

    PubMed

    Suzuki, Satoshi; Saitoh, Akiyoshi; Ohashi, Masanori; Yamada, Misa; Oka, Jun-Ichiro; Yamada, Mitsuhiko

    2016-05-01

    The medial prefrontal cortex is a heterogeneous cortical structure composed of several nuclei, including the prelimbic (PL) and infralimbic (IL) cortices. We previously demonstrated in mice that PL activation with the sodium channel activator veratrine induces anxiety-like behaviors. However, the role of IL in the regulation of anxiety-like behaviors remained unclear. Therefore, in the present study, we investigated the role of the IL in the regulation of anxiety-like behaviors using pharmacological activation model with veratrine, and compared it with the role of the PL. Extracellular glutamate levels were measured by in vivo microdialysis-HPLC with an electrochemical detector, and behaviors were assessed using the open field test. In this study, extracellular glutamate levels rose significantly after perfusion of veratrine in the IL and PL. Interestingly, the PL activation produced anxiety-like behaviors, whereas the activation of the IL produced no anxiety-like behavior in mice. Although the IL is adjacent to the PL, these two regions of the brain have differential functions in the expression of anxiety-like behaviors.

  6. GFAP expression in astrocytes of suprachiasmatic nucleus and medial preoptic area are differentially affected by malnutrition during rat brain development.

    PubMed

    Mendonça, João Esmeraldo Frota; Vilela, Maria Cristina Ramos; Bittencourt, Heitor; Lapa, Raíssa Maria; Oliveira, Francisco Gilberto; Alessio, Maria Luíza Martins; Guedes, Rubem Carlos Araújo; De Oliveira Costa, Miriam Stela Maris; Da Costa, Belmira Lara da Silveira Andrade

    2004-08-01

    The aim of the present study was investigate, in young rats, the effects of malnutrition on astrocyte distribution of two hypothalamic regions, the circadian pacemaker suprachiasmatic nucleus (SCN) and the medial preoptic area (MPA). Control rats were born from mothers fed on commercial diet since gestation and malnourished rats from mothers fed on multideficient diet, from the beginning of gestation (GLA group) or from the onset of lactation (LA group). After weaning, pups received ad libitum the same diet as their mothers, and were maintained under a 12/12 h light/dark cycle. The animals were analyzed either at 30-33, or 60-63 days of life. Brain coronal sections (50 microm) were processed to visualize glial fibrillary acidic protein (GFAP) immunoreactivity. Compared to control rats, both malnourished groups of 30 and 60 days exhibited a reduced number of GFAP-immunoreactive astrocytes in the SCN. The total GFAP-immunoreactive area in the SCN of the GLA group differed from the control group at both age ranges analyzed. The GFAP expression as measured by the relative optical density (ROD) exhibited a 50-60% reduction in the MPA in both malnourished groups, compared to controls. The results suggest that malnutrition early in life leads to alterations in gliogenesis or glial cell proliferation in both nuclei, being these alterations greater in the MPA. Compensatory plasticity mechanisms in the GFAP-expression seem to be developed in the astrocyte differentiation process in the SCN, especially when the malnutrition is installed from the lactation.

  7. Differential role of gonadal hormones on kainic acid-induced neurodegeneration in medial amygdaloid nucleus of female and male rats.

    PubMed

    Pereno, G L; Beltramino, C A

    2009-10-20

    Sex hormones contribute to modulating brain functions throughout the life span. It has been suggested that estrogen prevents neuronal loss in different areas of the CNS such as the hippocampus. However there are less consistent data on its effects on the amygdala. Kainic acid (KA) is used to produce seizures that mimic those of temporal lobe epilepsy in humans. At high doses in animal models, KA induces neurotoxicity, particularly in the medial amygdaloid nuclei (MeA). It is uncertain whether the gonadal hormones are protective or not against this neurotoxicity in the MeA. Here we show that a single dose of KA induces neurodegeneration in the subnuclei of the MeA of rats with different degrees of intensity in males and females. A differential neuroprotective effect of the gonadal hormones was also observed. In diestrous rats, massive neuronal death similar to that in the ovariectomized females was detected. MeA neurons of proestrous rats, like the ovariectomized treated with estrogen, were significantly less affected by the KA. Testosterone produced a mild neuroprotective action, but dihydrotestosterone did not protect. A similar pattern was observed in all male groups. Together, the results indicate that estrogen protects MeA neurons from KA neurotoxicity. Androgens are only partially neuroprotective, with this effect being found only in testosterone, probably through its conversion to estrogen by aromatase.

  8. Differential displacement of the human soleus and medial gastrocnemius aponeuroses during isometric plantar flexor contractions in vivo.

    PubMed

    Bojsen-Møller, Jens; Hansen, Philip; Aagaard, Per; Svantesson, Ulla; Kjaer, Michael; Magnusson, S Peter

    2004-11-01

    The human triceps surae muscle-tendon complex is a unique structure with three separate muscle compartments that merge via their aponeuroses into the Achilles tendon. The mechanical function and properties of these structures during muscular contraction are not well understood. The purpose of the study was to investigate the extent to which differential displacement occurs between the aponeuroses of the medial gastrocnemius (MG) and soleus (Sol) muscles during plantar flexion. Eight subjects (mean +/- SD; age 30 +/- 7 yr, body mass 76.8 +/- 5.5 kg, height 1.83 +/- 0.06 m) performed maximal isometric ramp contractions with the plantar flexor muscles. The experiment was performed in two positions: position 1, in which the knee joint was maximally extended, and position 2, in which the knee joint was maximally flexed (125 degrees ). Plantarflexion moment was assessed with a strain gauge load cell, and the corresponding displacement of the MG and Sol aponeuroses was measured by ultrasonography. Differential shear displacement of the aponeurosis was quantified by subtracting displacement of Sol from that of MG. Maximal plantar flexion moment was 36% greater in position 1 than in position 2 (132 +/- 20 vs. 97 +/- 11 N.m). In position 1, the displacement of the MG aponeurosis at maximal force exceeded that of the Sol (12.6 +/- 1.7 vs. 8.9 +/- 1.5 mm), whereas in position 2 displacement of the Sol was greater than displacement of the MG (9.6 +/- 1.0 vs. 7.9 +/- 1.2 mm). The amount and "direction" of shear between the aponeuroses differed significantly between the two positions across the entire range of contraction, indicating that the Achilles tendon may be exposed to intratendinous shear and stress gradients during human locomotion.

  9. Arthroscopically assisted meniscal allograft transplantation with and without combined anterior cruciate ligament reconstruction.

    PubMed

    Yoldas, Erol A; Sekiya, Jon K; Irrgang, James J; Fu, Freddie H; Harner, Christopher D

    2003-05-01

    The menisci provide a vital role in load transmission across the knee joint as well as contribute to knee stability, particularly in the ACL-deficient knee. Loss of the meniscus, in part or in total, significantly alters joint function and predisposes the articular cartilage to degenerative changes, which has been well documented both clinically and radiographically. This study examined clinical and patient-reported outcomes following meniscal allograft transplantation with and without combined ACL reconstruction in a select group of 31 patients with complaints of pain and/or instability (34 meniscal allografts); 11 underwent isolated meniscal transplantation and 20 meniscal transplantation combined with ACL reconstruction. Bony fixation was performed with bone plugs for medial transplants and using a bone bridge for lateral transplants. All patients completed several knee-specific and general measures of health-related quality of life and underwent a comprehensive physical examination. Flexion weightbearing PA radiographs at latest follow-up were compared to those obtained preoperatively. Mean follow-up was 2.9 years (range 2-5.5 years). The Activities of Daily Living and Sports Activities Scale scores were 86+/-11 and 78+/-16, respectively, and the average Lysholm score was 84+/-14. There were no significant differences in these scores based upon which meniscus (medial or lateral) was transplanted, concurrent ACL reconstruction, or the degree of chondrosis at arthroscopy. SF-36 scores indicated that patients were functioning at a level similar to the age- and sex-matched population. Twenty-two patients stated they were greatly improved, 8 were somewhat improved, 1 was without change. All but one patient reported that knee function and level of activity were normal or nearly normal. The average loss of motion compared to the noninvolved side was 3 degrees for extension and 9 degrees for flexion. All but one patient had a negative or 1+ Lachman's test. The

  10. Association Between Meniscal and Chondral Lesions and Timing of Anterior Cruciate Ligament Reconstruction

    PubMed Central

    de Campos, Gustavo Constantino; Nery, Wilton; Teixeira, Paulo Eduardo Portes; Araujo, Paulo Henrique; Alves, Wilson de Mello

    2016-01-01

    Background: Rupture of the anterior cruciate ligament (ACL) is a common sports injury and is known to be associated with an increased risk of knee osteoarthritis. Several studies have indicated that the risk of additional injuries to the menisci and articular cartilage increases with delays in the treatment of ACL tears. However, no consensus has been reached regarding the ideal timing for ACL reconstruction in terms of preventing secondary lesions. Purpose: To determine how the time elapsed between an ACL lesion and its reconstruction affects the incidence of meniscal and chondral lesions. Study Design: Case series; Level of evidence, 4. Methods: Medical records of 764 patients who underwent primary ACL reconstruction were reviewed. Data from arthroscopic findings that included information about meniscal lesions and full-thickness articular cartilage lesions at the time of surgery were collected. The association between time elapsed between ACL lesion and reconstruction surgery and incidence of articular cartilage and meniscal lesions was analyzed by chi-square or Fisher exact test. The risk of secondary lesion was calculated by odds ratios (ORs) obtained from simple logistic regression analysis. Results: A positive correlation was observed between time after injury and the presence of any articular lesions (P = .003), cartilage lesions (P = .01), and medial meniscus lesions (P < .001). When analyzing the risk of secondary lesion relative to the reference period (<2 months), it was observed that the odds of finding any articular injury at the time of ACL reconstruction increased when the time from ACL injury to surgery was between 12 and 24 months (OR = 2.62) and >24 months (OR = 5.88). Furthermore, the odds of lesions on the medial meniscus increased when the timing between injury and surgery was 6 to 12 months (OR = 2.71) and continued to increase when the timing was 12 to 24 months (OR = 3.78) and >24 months (OR = 9.07). Conclusion: Associated articular lesions

  11. Tensile forces at the porcine anterior meniscal horn attachment.

    PubMed

    Stärke, Christian; Kopf, Sebastian; Gröbel, Karl-Heinz; Becker, Roland

    2009-12-01

    Tibiofemoral compression causes circumferential tension in the knee meniscus, which is transferred to the tibial bone at the anterior and posterior attachments. The objective of the study was to measure the resulting tensile forces at the horn attachment in a porcine model. The anterior horn attachment of the porcine medial meniscus (n = 10) was separated from the surrounding bone with a core reamer. A force transducer was installed such that tensile forces acting upon the now mobile horn attachment could be measured. The tibiofemoral joint was loaded in compression, starting at a preload of 30 N, with three 150-N increments, giving 180, 330, and 480 N load. Flexion angles of 0, 30, and 60 degrees were investigated. The average resultant tension at the horn attachment was 26.3, 40.6, and 55.4 N with full extension, 29.2, 47.8, and 62.2 N at 30 degrees flexion and 30.1, 49.6, and 68.1 N at 60 degrees flexion. The tibiofemoral compression had a significant effect on the tension (p < 0.001), whereas no influence of the flexion angle was found (p = 0.291). The study demonstrates that tibiofemoral compressive loads cause considerable tensile forces at the anterior meniscal horn attachment. The data are of interest for models of the repair or replacement of the knee menisci.

  12. Regional and depth variability of porcine meniscal mechanical properties through biaxial testing.

    PubMed

    Kahlon, A; Hurtig, M B; Gordon, K D

    2015-01-01

    The menisci in the knee joint undergo complex loading in-vivo resulting in a multidirectional stress distribution. Extensive mechanical testing has been conducted to investigate the tissue properties of the knee meniscus, but the testing conditions do not replicate this complex loading regime. Biaxial testing involves loading tissue along two different directions simultaneously, which more accurately simulates physiologic loading conditions. The purpose of this study was to report mechanical properties of meniscal tissue resulting from biaxial testing, while simultaneously investigating regional variations in properties. Ten left, fresh porcine joints were obtained, and the medial and lateral menisci were harvested from each joint (twenty menisci total). Each menisci was divided into an anterior, middle and posterior region; and three slices (femoral, deep and tibial layers) were obtained from each region. Biaxial and constrained uniaxial testing was performed on each specimen, and Young's moduli were calculated from the resulting stress strain curves. Results illustrated significant differences in regional mechanical properties, with the medial anterior (Young's modulus (E)=11.14 ± 1.10 MPa), lateral anterior (E=11.54 ± 1.10 MPa) and lateral posterior (E=9.0 ± 1.2 MPa) regions exhibiting the highest properties compared to the medial central (E=5.0 ± 1.22 MPa), medial posterior (E=4.16 ± 1.13 MPa) and lateral central (E=5.6 ± 1.20 MPa) regions. Differences with depth were also significant on the lateral meniscus, with the femoral (E=12.7 ± 1.22 MPa) and tibial (E=8.6 ± 1.22 MPa) layers exhibiting the highest Young's moduli. This data may form the basis for future modeling of meniscal tissue, or may aid in the design of synthetic replacement alternatives.

  13. Diagnostic value of the clinical investigation in acute meniscal tears combined with anterior cruciate ligament injury using arthroscopic findings as golden standard.

    PubMed

    Speziali, A; Placella, G; Tei, M M; Georgoulis, A; Cerulli, G

    2016-04-01

    The main purpose of our study was to evaluate the accuracy of clinical investigation for meniscal tears associated with ACL injuries. We hypothesized that combined ACL injury can decrease the accuracy of clinical examination in acute onset. One hundred and thirty-seven patients with a mean age of 28.5 years (from 12 to 55) were prospectively examined for acute combined ACL and meniscal injuries, between March and November 2012 at our department. For meniscal tears, clinical examination was performed using McMurray test, Apley test and medial and lateral joint line tenderness. The diagnoses of ACL tear were made using Lachman test, jerk test and pivot-shift test, anterior drawer test and KT-2000 side-to-side difference. Each patient was examined using X-ray and MRI. All the patients underwent arthroscopic surgery performed by the same surgeon within 6 weeks after the injury. Finally, using the arthroscopic findings as gold standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of clinical investigation and MRI were evaluated. The specificity of clinical investigation was 63.5 and 46.0 % and the sensitivity was 74.4 and 77.3 % for the medial meniscus and the lateral meniscus, respectively. Overall, the accuracy of the clinical investigation was 70.3 % for the MM and 65.5 % for the lateral meniscus. The accuracy of MRI investigation was 76.4 and 69.5 % for medial and lateral meniscus, respectively. In combined acute ACL injury and meniscal tears, we have found a decreased accuracy of the clinical investigation. The remnants of the torn ACL and the synovitis increased the rate of false positives, and it could simulate meniscal tears. However, clinical investigation can provide sufficient information for the treatment decision and MRI can be avoided as a routine diagnostic tool. Level II, prospective study.

  14. Development and Preliminary Validation of a Meniscal Symptom Index

    PubMed Central

    Niu, Nina N.; Losina, Elena; Martin, Scott D.; Wright, John; Solomon, Daniel H.; Katz, Jeffrey N.

    2010-01-01

    Objective In diagnosing symptomatic meniscal tear, clinicians often query patients with a “checklist” of symptoms such as “popping” or “catching.” There has been little research on the reliability or diagnostic value of these terms. Methods We developed questions to elicit the presence of 11 “checklist” symptoms associated with meniscal tear and administered a survey with both “checklist” and expanded descriptions to study subjects. We examined reliability of checklist and expanded versions of each item. Validity was evaluated in relation to the clinical diagnosis of symptomatic meniscal tear, which consisted of the clinical impression of the treating orthopedic surgeon based upon physical exam, history and MRI. We developed a Meniscal Symptom Index, calculated as the sum of those expanded descriptive items that were independently associated with symptomatic meniscal tear in multivariate logistic regression. Results 300 individuals (mean age 52 ± 12 years, 66% female) completed the survey. 121 had symptomatic meniscal tear. Test-retest reliability was higher for expanded descriptions than for checklist items. The Meniscal Symptom Index consisted of 4 expanded items: localized pain, clicking, catching, and giving way. Among subjects with none of these symptoms, 16% (95% CI 2 – 30%) had symptomatic meniscal tear, whereas among those with all 4 symptoms, 76% (95% CI 63 – 88%) had symptomatic meniscal tear (p-value for trend = 0.0001). Conclusion Clinicians should use expanded symptom definitions when querying patients about meniscal symptoms. A newly-developed Meniscal Symptom Index holds promise as a diagnostic tool and merits further validation. PMID:20862684

  15. The Urgent Need for Evidence in Arthroscopic Meniscal Surgery.

    PubMed

    Monk, Paul; Garfjeld Roberts, Patrick; Palmer, Antony J R; Bayliss, Lee; Mafi, Reza; Beard, David; Hopewell, Sally; Price, Andrew

    2017-03-01

    Arthroscopic surgery of the knee is one of the most frequently performed orthopaedic procedures. One-third of these procedures are performed for meniscal injuries. It is essential that this commonly performed surgery be supported by robust evidence. To compare the effectiveness of arthroscopic surgery for meniscal injuries in all populations. Systematic review. An online search was conducted for randomized controlled trials (RCTs) and systematic reviews (SRs) that compared treatment options for meniscal injury. The following databases (inception to April 2015) were included in the search: CENTRAL; MEDLINE; EMBASE; NHS Evidence; National Guideline Clearing House, Database of Abstracts of Reviews of Effects, Health Technology Assessment; ISRCTN; Clinicaltrials.gov ; WHO trials platform. Only studies whose participants were selected on the basis of meniscal injury were included; no restrictions were placed on patient demographics. Two independent reviewers applied AMSTAR (A Measurement Tool to Assess Systematic Reviews) criteria for SRs and the Cochrane Collaboration risk-of-bias tool for RCTs. Nine RCTs and 8 SRs were included in the review. No difference was found between arthroscopic meniscal debridement compared with nonoperative management as a first-line treatment strategy for patients with knee pain and a degenerative meniscal tear (mean difference: Knee injury and Osteoarthritis Outcome Score, 1.6 [95% CI, -2.2 to 5.2], pain visual analog scale, -0.06 [95% CI, -0.28 to 0.15]). Some evidence was found to indicate that patients with resistant mechanical symptoms who initially fail nonoperative management may benefit from meniscal debridement No studies compared meniscal repair with meniscectomy or nonoperative management. Initial evidence suggested that meniscal transplant might be favorable in certain patient groups. Further evidence is required to determine which patient groups have good outcomes from each intervention. Given the current widespread use of

  16. 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

  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

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

    2016-01-01

    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. 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. 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. 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.

  18. Differential modulation of feline defensive rage behavior in the medial hypothalamus by 5-HT1A and 5-HT2 receptors.

    PubMed

    Hassanain, M; Bhatt, S; Siegel, A

    2003-08-15

    Previous studies have established that the expression of defensive rage behavior in the cat is mediated over reciprocal pathways that link the medial hypothalamus and the dorsolateral quadrant of the midbrain periaqueductal gray matter (PAG). The present study was designed to determine the roles played by 5-HT(1A) and 5-HT(2C) receptors in the medial hypothalamus on the expression of defensive rage behavior elicited from electrical stimulation of the PAG. Monopolar stimulating electrodes were placed in the midbrain PAG from which defensive rage behavior could be elicited by electrical stimulation. During the course of this study, defensive rage was determined by measuring the latency of the "hissing" component of this behavior. Cannula-electrodes were implanted into sites within the medial hypothalamus from which defensive rage behavior could also be elicited by electrical stimulation in order that serotonergic compounds could be microinjected into behaviorally identifiable regions of the hypothalamus at a later time. Microinjections of the 5-HT(1A) receptor agonist 8-OHDPAT (0.1, 1.0 and 3.0 nmol) into the medial hypothalamus suppressed PAG-elicited hissing in a dose-dependent manner. Administration of the 5-HT(1A) antagonist p-MPPI (3.0 nmol) blocked the suppressive effects of 8-OHDPAT upon hissing. The suppressive effects of 8-OHDPAT were specific to defensive rage behavior because this drug (3 nmol) facilitated quiet biting attack. Microinjections of the 5-HT(2C) receptor agonist (+/-)-DOI hydrochloride into the medial hypothalamus (0.5, 1.0, and 3.0 nmol) facilitated the occurrence of PAG-elicited hissing in a dose-dependent manner. In turn, these facilitating effects were blocked by pretreatment with the selective 5-HT(2) antagonist, LY-53,857, which was microinjected into the same medial hypothalamic site. The findings of this study provide evidence that activation of 5-HT(1A) and 5-HT(2) receptors within the medial hypothalamus exert differential modulatory

  19. 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

  20. Novel organ-slice culturing system to simulate meniscal repair: Proof of concept using a synovium-based pool of meniscoprogenitor cells.

    PubMed

    Hunziker, Ernst B; Lippuner, Kurt; Keel, Marius J B; Shintani, Nahoko

    2016-09-01

    Meniscal injuries can occur secondary to trauma or be instigated by the changes in knee-joint function that are associated with aging, osteo- and rheumatoid arthritis, disturbances in gait, and obesity. Sixty percent of persons over 50 years of age manifest signs of meniscal pathology. The surgical and arthroscopic measures that are currently implemented to treat meniscal deficiencies bring only transient relief from pain and effect but a temporary improvement in joint function. Although tissue-engineering-based approaches to meniscal repair are now being pursued, an appropriate in-vitro model has not been conceived. The aim of this study was to develop an organ-slice culturing system to simulate the repair of human meniscal lesions in vitro. The model consists of a ring of bovine meniscus enclosing a chamber that represents the defect and reproduces its sequestered physiological microenvironment. The defect, which is closed with a porous membrane, is filled with fragments of synovial tissue, as a source of meniscoprogenitor cells, and a fibrin-embedded, calcium-phosphate-entrapped depot of the meniscogenic agents BMP-2 and TGF-β1. After culturing for 2 to 6 weeks, the constructs were evaluated histochemically and histomorphometrically, as well as immunohistochemically, for the apoptotic marker caspase 3 and collagen types I and II. Under the defined conditions, the fragments of synovium underwent differentiation into meniscal tissue, which bonded with the parent meniscal wall. Both the parent and the neoformed meniscal tissue survived the duration of the culturing period without significant cell losses. The concept on which the in-vitro system is based was thus validated. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1588-1596, 2016.

  1. Selective serotonin receptor stimulation of the medial nucleus accumbens causes differential effects on food intake and locomotion.

    PubMed

    Pratt, Wayne E; Blackstone, Kaitlin; Connolly, Megan E; Skelly, Mary Jane

    2009-10-01

    Substantial evidence suggests that pharmacological manipulations of neural serotonin pathways influence ingestive behaviors. Despite the known role of the nucleus accumbens in directing appetitive and consummatory behavior, there has been little examination of the influences that serotonin receptors may play in modulating feeding within nucleus accumbens circuitry. In these experiments, the authors examined the effects of bilateral nucleus accumbens infusions of the 5-HT1/7 receptor agonist 5-CT (at 0.0, 0.5, 1.0, or 4.0 microg/0.5 microl/side), the 5-HT receptor agonist EMD 386088 (at 0.0, 1.0, and 4.0 microg/0.5 microl/side), or the 5-HT2C preferential agonist RO 60-0175 (at 0.0, 2.0, or 5.0 microg/0.5 microl/side) on food intake and locomotor activity in the rat. Intra-accumbens infusions of 5-CT caused a dose-dependent reduction of food intake and rearing behavior, both in food-restricted animals given 2-hr free access to Purina Protab RMH 3000 Chow, as well as in nondeprived rats offered 2-hr access to a highly palatable fat/sucrose diet. In contrast, stimulation of 5-HT receptors with EMD 386088 caused a dose-dependent increase of intake under both feeding conditions, without affecting measures of locomotion. Infusions of the moderately selective 5-HT2C receptor agonist RO 60-0175 had no effects on feeding or locomotor measures in food-restricted animals, but did reduce intake of the fat/sucrose in nonrestricted animals at the 2.0 microg, but not the 5.0 microg dose. Intra-accumbens infusions of selective antagonists for the 5-HT (SB 269970), 5-HT (SB 252585), and 5-HT2C (RS 102221) receptors did not affect locomotion, and demonstrated no lasting changes in feeding for any of the groups tested. These data are the first to suggest that the activation of different serotonin receptor subtypes within the feeding circuitry of the medial nucleus accumbens differentially influence consummatory behavior.

  2. Sports injury, occupational physical activity, joint laxity, and meniscal damage.

    PubMed

    Baker, Paul; Coggon, David; Reading, Isabel; Barrett, David; McLaren, Magnus; Cooper, Cyrus

    2002-03-01

    To investigate the risk factors for meniscal damage, an important determinant of knee osteoarthritis. We studied 243 men and women aged 20-59 years in whom the diagnosis of a meniscal tear was confirmed for the first time at arthroscopy, over a 25 month period, in 2 British hospitals. Each case was compared with one or 2 community controls, matched by age and sex, who were registered with the same general practitioner. Information on exposure to risk factors was obtained by a structured questionnaire and physical examination. Meniscal tear was strongly associated with participation in sports during the 12 months preceding the onset of symptoms; the risk was particularly high for soccer (OR 3.7; 95% CI 2.1-6.6). Higher body mass index and occupational kneeling (OR 3.8; 95% CI 1.3-11.0) and squatting (OR 2.9; 95% CI 1.0-8.0) were associated with an increased risk of degenerative meniscal lesions, after adjustment for social class, joint laxity, and sports participation. Joint laxity was associated with degenerative meniscal lesions independently of occupational physical activity, sports, and obesity. Our results confirm the importance of sporting activities entailing knee torsion in acute meniscal tear. They also point to a role for occupational activity, adiposity, and joint laxity in the pathogenesis of degenerative meniscal lesions. Modifying these mechanical risk factors may serve to reduce the risk of meniscal injury and may also help to prevent later knee osteoarthritis.

  3. 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

  4. Comparison of Medial and Lateral Meniscus Root Tears.

    PubMed

    Koo, Ji Hyun; Choi, Sang-Hee; Lee, Seung Ah; Wang, Joon Ho

    2015-01-01

    The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients' ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29-71 years) and 30 years (range: 14-62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is common in

  5. 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.

  6. Arthroscopic trans-portal deep medial collateral ligament pie-crusting release.

    PubMed

    Atoun, Ehud; Debbi, Ronen; Lubovsky, Omri; Weiler, Andreas; Debbi, Eytan; Rath, Ehud

    2013-02-01

    Arthroscopic treatments of meniscal injuries of the knee are among the most common orthopaedic procedures performed. Adequate visualization of the posterior horn of the medial meniscus might be challenging, especially in patients with tight medial compartments. In these cases instrument manipulation in an attempt to reach the posterior horn of the meniscus can cause an iatrogenic chondral injury because of the narrow medial joint space. A transcutaneous medial collateral ligament (MCL) pie-crusting release facilitates expansion of the medial joint space in a case of a tight medial compartment. Nevertheless, it might cause injury to the superficial MCL, infection, and pain and injury to the saphenous nerve because of multiple needle punctures of the skin. We describe an inside-out, arthroscopic deep MCL pie-crusting release, which allows access to the medial meniscus through the anterior approach to provide good visualization of the footprint and sufficient working space.

  7. 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.

  8. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    NASA Astrophysics Data System (ADS)

    Pawelec, K. M.; Best, S. M.; Cameron, R. E.; Wardale, R. J.

    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.

  9. Anterolateral ligament abnormalities in patients with acute anterior cruciate ligament rupture are associated with lateral meniscal and osseous injuries.

    PubMed

    Van Dyck, Pieter; Clockaerts, Stefan; Vanhoenacker, Filip M; Lambrecht, Valérie; Wouters, Kristien; De Smet, Eline; Gielen, Jan L; Parizel, Paul M

    2016-10-01

    To determine the frequency of anterolateral ligament (ALL) injury in patients with acute anterior cruciate ligament (ACL) rupture and to analyse its associated injury patterns. Ninety patients with acute ACL rupture for which MRI was obtained within 8 weeks after the initial trauma were retrospectively identified. Two radiologists assessed the status of the ALL on MRI by consensus. The presence or absence of an ALL abnormality was compared with the existence of medial and lateral meniscal tears diagnosed during arthroscopy. Associated collateral ligament and osseous injuries were documented with MRI. Forty-one of 90 knees (46 %) demonstrated ALL abnormalities on MRI. Of 49 knees with intact ALL, 15 (31 %) had a torn lateral meniscus as compared to 25 torn lateral menisci in 41 knees (61 %) with abnormal ALL (p = 0.008). Collateral ligament (p ≤ 0.05) and osseous injuries (p = 0.0037) were more frequent and severe in ALL-injured as compared with ALL-intact knees. ALL injuries are fairly common in patients with acute ACL rupture and are statistically significantly associated with lateral meniscal, collateral ligament and osseous injuries. • ALL injuries are fairly common in patients with acute ACL rupture. • ALL injuries are highly associated with lateral meniscal and osseous injuries. • MRI assessment of ACL-injured knees should include evaluation of the ALL.

  10. Differential recruitment of the hippocampus, medial prefrontal cortex, and the human motion complex during path integration in humans.

    PubMed

    Wolbers, Thomas; Wiener, Jan M; Mallot, Hanspeter A; Büchel, Christian

    2007-08-29

    Path integration, the ability to sense self-motion for keeping track of changes in orientation and position, constitutes a fundamental mechanism of spatial navigation and a keystone for the development of cognitive maps. Whereas animal path integration is predominantly supported by the head-direction, grid, and place cell systems, the neural foundations are not well understood in humans. Here we used functional magnetic resonance imaging and a virtual rendition of a triangle completion paradigm to test whether human path integration recruits a cortical system similar to that of rodents and nonhuman primates. Participants traveled along two legs of a triangle before pointing toward the starting location. In accordance with animal models, stronger right hippocampal activation predicted more accurate updating of the starting location on a trial-by-trial basis. Moreover, between-subjects fluctuations in response consistency were negatively correlated with bilateral hippocampal and medial prefrontal activation, and bilateral recruitment of the human motion complex (hMT+) covaried with individual path integration capability. Given that these effects were absent in a perceptual control task, the present study provides the first evidence that visual path integration is related to the dynamic interplay of self-motion processing in hMT+, higher-level spatial processes in the hippocampus, and spatial working memory in medial prefrontal cortex.

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

    PubMed Central

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

    2014-01-01

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

  12. Comparison of postoperative magnetic resonance imaging and second-look arthroscopy for evaluating meniscal allograft transplantation.

    PubMed

    Kim, Jong-Min; Kim, Jong-Min; Jeon, Byeong-Sam; Lee, Chang-Rack; Lim, Sung-Joon; Kim, Kyung-Ah; Bin, Seong-Il

    2015-05-01

    The aim of this study was to compare the magnetic resonance imaging (MRI) evaluation of transplanted meniscal allograft with second-look arthroscopy and evaluate the sensitivity, specificity, and accuracy of MRI for assessing graft status. From 1996 to 2012, among 290 knees that underwent meniscal allograft transplantation and received follow-up examination for more than 1 year, those knees that underwent second-look arthroscopy were reviewed. Patients with no postoperative MRI and patients with a time gap between postoperative MRI and second-look arthroscopy of more than 3 months were excluded. Anatomically, the meniscus was divided into 3 segments: anterior one-third, mid body, and posterior one-third. Each part of the meniscus was evaluated using both methods. Grade 3 MRI signal intensity was diagnosed as a meniscal tear radiologically. By use of second-look arthroscopy as the standard, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of postoperative MRI were assessed in each segment of the grafts. Twenty knees were retrospectively enrolled. The specificity, PPV, and accuracy for the anterior one-third were lower than those for the mid body and posterior one-third (specificity of 35.3% v 91.7% and 90%, respectively; PPV of 21.4% v 87.5% and 90.9%, respectively; and accuracy of 45% v 90% and 95%, respectively). However, the sensitivity and NPV were similar among the anterior one-third, mid body, and posterior one-third (sensitivity of 100%, 87.5%, and 100%, respectively; and NPV of 100%, 91.7%, and 100%, respectively). There were no significant differences in the comparison between the diagnostic MRI values of lateral grafts and medial grafts. Of 5 cases that showed grade 3 signal at only the anterior one-third section, 60% had no clinical signs. There were no graft tears in any cases. The anterior one-third of grafts showed low specificity, PPV, and accuracy of postoperative MRI compared with the mid

  13. Readability of Online Sources Regarding Meniscal Tears.

    PubMed

    Hodax, Jonathan D; Baird, Grayson L; McBride, Trevor; Owens, Brett D

    2017-09-01

    Meniscal injuries are extremely common, with an incidence of 8.3 per 1,000 person/years in young, active individuals. Patients often turn to the internet to glean information about their injuries, and even to guide decision making about treatment. Much research has been done demonstrating that a reading level of eighth grade or lower is appropriate for accurately communicating written information to patients, yet medical practitioners often fail to meet this requirement. To better examine the information patients receive about meniscal injuries, we set out to evaluate the reading level and content of three commonly used search terms on the three search engines with the largest market share. The authors examined the keywords "meniscus tear," "meniscus tear treatment," and "knee pain meniscus" on the three highest market share search engines. The top 10 results from each search were included, and redundancies identified. Unique Web sites were evaluated for source, word count, reading level, and content including advertisements, diagrams, photographs, nonoperative and operative options, and accurate medical information. A total of 23 unique Web sites were identified in our search, including 13 public education sources, 6 academic institutions, and 4 private physicians/groups. Average grade levels of articles ranged from 9.4 to 14.2 (mean, 11.14; standard deviation [SD] 1.46), and Flesch-Kincaid reading ease scores ranged from 23.9 to 68.7 (mean, 55.31; SD, 10.11). Pages from public sources required the highest level of readability (11.6, 95% confidence interval [CI]: 9.8-13.2), which was significantly higher than private (11.0, 95% CI: 9.3, 12.7]) and academic (10.9, 95% CI: 8.9-12.9), p = 0.007 and p = 0.002, respectively. Further efforts to make appropriate health information available to patients are needed. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  14. Inactivation of the dorsal hippocampus or the medial prefrontal cortex impairs retrieval but has differential effect on spatial memory reconsolidation.

    PubMed

    Rossato, Janine I; Köhler, Cristiano A; Radiske, Andressa; Bevilaqua, Lia R M; Cammarota, Martín

    2015-11-01

    Active memories can incorporate new information through reconsolidation. However, the notion that memory retrieval is necessary for reconsolidation has been recently challenged. Non-reinforced retrieval induces hippocampus and medial prefrontal cortex (mPFC)-dependent reconsolidation of spatial memory in the Morris water maze (MWM). We found that the effect of protein synthesis inhibition on this process is abolished when retrieval of the learned spatial preference is hindered through mPFC inactivation but not when it is blocked by deactivation of dorsal CA1. Our results do not fully agree with the hypothesis that retrieval is unneeded for reconsolidation. Instead, they support the idea that a hierarchic interaction between the hippocampus and the mPFC controls spatial memory in the MWM, and indicate that this cortex is sufficient to retrieve the information essential to reconsolidate the spatial memory trace, even when the hippocampus is inactivated.

  15. Differential expression of voltage-gated K+ currents in medial septum/diagonal band complex neurons exhibiting distinct firing phenotypes.

    PubMed

    Garrido-Sanabria, Emilio R; Perez-Cordova, Miriam G; Colom, Luis V

    2011-08-01

    The medial septum/diagonal band complex (MSDB) controls hippocampal excitability, rhythms and plastic processes. Medial septal neuronal populations display heterogeneous firing patterns. In addition, some of these populations degenerate during age-related disorders (e.g. cholinergic neurons). Thus, it is particularly important to examine the intrinsic properties of theses neurons in order to create new agents that effectively modulate hippocampal excitability and enhance memory processes. Here, we have examined the properties of voltage-gated, K(+) currents in electrophysiologically-identified neurons. These neurons were taken from young rat brain slices containing the MS/DB complex. Whole-cell, patch recordings of outward currents were obtained from slow firing, fast-spiking, regular-firing and burst-firing neurons. Slow firing neurons showed depolarization-activated K(+) current peaks and densities larger than in other neuronal subtypes. Slow firing total current exhibited an inactivating A-type current component that activates at subthreshold depolarization and was reliably blocked by high concentrations of 4-AP. In addition, slow firing neurons expressed a low-threshold delayed rectifier K(+) current component with slow inactivation and intermediate sensitivity to tetraethylammonium. Fast-spiking neurons exhibited the smaller I(K) and I(A) current densities. Burst and regular firing neurons displayed an intermediate firing phenotype with I(K) and I(A) current densities that were larger than the ones observed in fast-spiking neurons but smaller than the ones observed in slow-firing neurons. In addition, the prevalence of each current differed among electrophysiological groups with slow firing and regular firing neurons expressing mostly I(A) and fast spiking and bursting neurons exhibiting mostly delayer rectifier K(+) currents with only minimal contributions of the I(A). The pharmacological or genetic modulations of these currents constitute an important target

  16. Learning an Operant Conditioning Task Differentially Induces Gliogenesis in the Medial Prefrontal Cortex and Neurogenesis in the Hippocampus

    PubMed Central

    Rapanelli, Maximiliano; Frick, Luciana Romina; Zanutto, Bonifacio Silvano

    2011-01-01

    Circuit modification associated with learning and memory involves multiple events, including the addition and remotion of newborn cells trough adulthood. Adult neurogenesis and gliogenesis were mainly described in models of voluntary exercise, enriched environments, spatial learning and memory task; nevertheless, it is unknown whether it is a common mechanism among different learning paradigms, like reward dependent tasks. Therefore, we evaluated cell proliferation, neurogenesis, astrogliogenesis, survival and neuronal maturation in the medial prefrontal cortex (mPFC) and the hippocampus (HIPP) during learning an operant conditioning task. This was performed by using endogenous markers of cell proliferation, and a bromodeoxiuridine (BrdU) injection schedule in two different phases of learning. Learning an operant conditioning is divided in two phases: a first phase when animals were considered incompletely trained (IT, animals that were learning the task) when they performed between 50% and 65% of the responses, and a second phase when animals were considered trained (Tr, animals that completely learned the task) when they reached 100% of the responses with a latency time lower than 5 seconds. We found that learning an operant conditioning task promoted cell proliferation in both phases of learning in the mPFC and HIPP. Additionally, the results presented showed that astrogliogenesis was induced in the medial prefrontal cortex (mPFC) in both phases, however, the first phase promoted survival of these new born astrocytes. On the other hand, an increased number of new born immature neurons was observed in the HIPP only in the first phase of learning, whereas, decreased values were observed in the second phase. Finally, we found that neuronal maturation was induced only during the first phase. This study shows for the first time that learning a reward-dependent task, like the operant conditioning, promotes neurogenesis, astrogliogenesis, survival and neuronal

  17. Posteromedial meniscal tears may be missed during anterior cruciate ligament reconstruction.

    PubMed

    Peltier, Adrien; Lording, Timothy D; Lustig, Sébastien; Servien, Elvire; Maubisson, Laurent; Neyret, Philippe

    2015-04-01

    This study aimed to assess the benefit of using an arthroscopic intercondylar view and a posterior medial viewing portal during anterior cruciate ligament (ACL) reconstruction in the diagnosis of posterior horn of the medial meniscus (PHMM) tears. A secondary objective was to determine clinical and radiological risk factors for the PHMM. Forty-one patients undergoing isolated ACL reconstruction were prospectively evaluated. At ACL reconstruction, the PHMM was assessed using a standard 30° arthroscope in 3 sequential stages: a "classic" anterolateral portal view, an intercondylar view, and a view through a posteromedial portal. Thirty-nine patients were included (12 female patients and 27 male patients). A posteromedial tear of the medial meniscus was found in 17 patients using the anterolateral portal view. The intercondylar view identified 4 new additional lesions and extensions of 3 previously identified lesions. The posteromedial portal view identified 6 new lesions and 5 extensions of known lesions compared with the anterolateral portal view. Two lesions seen through the posteromedial portal were not identified by either the anterolateral portal view or the intercondylar view. Tears of the PHMM may be underdiagnosed by intraoperative assessment using only an anterolateral portal view during ACL reconstruction. The intercondylar view combined with a posteromedial portal aids in the diagnosis of PHMM tears and should be considered in routine ACL reconstruction to assess meniscal status, particularly when the interval from injury to surgery is prolonged. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  18. Nociceptive and sympathetic innervations in the abaxial part of the cranial horn of the equine medial meniscus: an immunohistochemical approach.

    PubMed

    Nemery, Elodie; Gabriel, Annick; Piret, Joëlle; Antoine, Nadine

    2016-12-01

    In athletic horses, diseases leading to lameness are of great importance due to the loss of performance and the resultant economic concerns. Although stifle lesions are frequent in the hindlimb, due to the large size and complexity of the joint, and although meniscal tears have been identified as the most common soft tissue injuries in this joint, little is known about the mechanism that causes the painful sensation and thus the lameness. The aim of our study was to highlight any peripheral fibres involved in meniscal nociception in five macroscopically sound cranial horns of the equine medial meniscus, which has been one of the most common sites reported for equine meniscal injuries. Immunohistochemical stainings were performed using antibodies against Substance P in order to identify nociceptive fibres; against tyrosine hydroxylase for detecting postganglionic sympathetic fibres; and against glial fibrillary acidic proteins in order to identify Schwann cells. Our work highlights for the first time the presence of nociceptive and sympathetic fibres in equine menisci. They were found in the abaxial part of the cranial horn of the equine medial meniscus. This study suggests that when the abaxial part is injured, the meniscus itself could be the source of pain. These findings could provide a better understanding of the clinical presentation of horses with meniscal injury and contribute towards improving therapeutic strategies to alleviate pain in cases of equine meniscal injury. © 2016 Anatomical Society.

  19. 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

  20. Satb1 is an activity-modulated transcription factor required for the terminal differentiation and connectivity of medial ganglionic eminence-derived cortical interneurons.

    PubMed

    Close, Jennie; Xu, Han; De Marco García, Natalia; Batista-Brito, Renata; Rossignol, Elsa; Rudy, Bernardo; Fishell, Gord

    2012-12-05

    Although previous work identified transcription factors crucial for the specification and migration of parvalbumin (PV)-expressing and somatostatin (SST)-expressing interneurons, the intrinsic factors required for the terminal differentiation, connectivity, and survival of these cell types remain uncharacterized. Here we demonstrate that, within subpopulations of cortical interneurons, Satb1 (special AT-rich binding protein) promotes terminal differentiation, connectivity, and survival in interneurons that express PV and SST. We find that conditional removal of Satb1 in mouse interneurons results in the loss of a majority of SST-expressing cells across all cortical layers, as well as some PV-expressing cells in layers IV and VI, by postnatal day 21. SST-expressing cells initially migrate to the cortex in Satb1 mutant mice, but receive reduced levels of afferent input and begin to die during the first postnatal week. Electrophysiological characterization indicates that loss of Satb1 function in interneurons results in a loss of functional inhibition of excitatory principal cells. These data suggest that Satb1 is required for medial ganglionic eminence-derived interneuron differentiation, connectivity, and survival.

  1. 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

  2. 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

  3. The Role of ΔFosB in the Medial Preoptic Area: Differential Effects of Mating and Cocaine History

    PubMed Central

    McHenry, Jenna A.; Robison, Christopher L.; Bell, Genevieve A.; Bolaños-Guzmán, Carlos A.; Vialou, Vincent V.; Nestler, Eric J.; Hull, Elaine M.

    2016-01-01

    The transcription factor deltaFosB (ΔFosB) is induced in the nucleus accumbens (NAc) by repeated exposure to drugs of abuse and natural rewards. Less is known about its role in other brain areas. Here, we compared the effects of mating versus cocaine history on induction of ΔFosB in the medial preoptic area (MPOA), an integral site for reproductive behavior, and in the NAc. ΔFosB immunoreactivity (ir) was increased in the MPOA of previously naïve and experienced male rats that mated the day before euthanasia, compared to unmated controls and experienced males with recent mating abstinence. Western immunoblots confirmed that the 35–37-kDa isoform of ΔFosB was increased more in recently mated males. Conversely, previous plus recent cocaine did not increase ΔFosB-ir in the MPOA, despite an increase in the NAc. Next, a viral vector expressing ΔFosB, its dominant negative antagonist ΔJunD, or green fluorescent protein (GFP) control, were microinjected bilaterally into the MPOA. ΔFosB overexpression impaired copulation and promoted female-directed aggression, compared to ΔJunD and control males. These data suggest that ΔFosB in the mPOA is expressed in an experience-dependent manner and affects systems that coordinate mating and aggression. PMID:27657309

  4. Medial canthus retiform hemangioendothelioma

    PubMed Central

    Al-Faky, Yasser H; Al-Mosallam, Abdul Rahman; Al-Rikabi, Ammar C; Al-Sohaibani, Mohammed O

    2014-01-01

    Retiform hemangioendothelioma (RH) is a distinct entity in the spectrum of vascular tumors with a high local recurrence rate. It is considered a low-grade, well-differentiated cutaneous angiosarcoma with low metastatic potential. We report here for the first time a case of medial canthus recurrent RH. It may be helpful in our practice to include RH as a differential diagnosis of eyelid lesions. It is noteworthy that the progressive course and recurrence tendency of RH might be misdiagnosed as angiosarcoma or basal cell carcinoma (BCC), if not expected and carefully evaluated by the pathologist. PMID:24817752

  5. Muscarinic Receptor Subtypes Differentially Control Synaptic Input and Excitability of Cerebellum-Projecting Medial Vestibular Nucleus Neurons

    PubMed Central

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

    2016-01-01

    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 is 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 postsynaptic 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 postsynaptic 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 postsynaptic mAChR involved in muscarinic excitation of cerebellum-projecting MVN neurons. Presynaptic 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. PMID:26823384

  6. Absence of lateral gastrocnemius activity and differential motor unit behavior in soleus and medial gastrocnemius during standing balance.

    PubMed

    Héroux, Martin E; Dakin, Christopher J; Luu, Billy L; Inglis, John Timothy; Blouin, Jean-Sébastien

    2014-01-15

    In a standing position, the vertical projection of the center of mass passes in front of the ankle, which requires active plantar-flexor torque from the triceps surae to maintain balance. We recorded motor unit (MU) activity in the medial (MG) and lateral (LG) gastrocnemius muscle and the soleus (SOL) in standing balance and voluntary isometric contractions to understand the effect of functional requirements and descending drive from different neural sources on motoneuron behavior. Single MU activity was recorded in seven subjects with wire electrodes in the triceps surae. Two 3-min standing balance trials and several ramp-and-hold contractions were performed. Lateral gastrocnemius MU activity was rarely observed in standing. The lowest thresholds for LG MUs in ramp contractions were 20-35 times higher than SOL and MG MUs (P < 0.001). Compared with MUs from the SOL, MG MUs were intermittently active (P < 0.001), had higher recruitment thresholds (P = 0.022), and greater firing rate variability (P < 0.001); this difference in firing rate variability was present in standing balance and isometric contractions. In SOL and MG MUs, both recruitment of new MUs (R(2) = 0.59-0.79, P < 0.01) and MU firing rates (R(2) = 0.05-0.40, P < 0.05) were associated with anterior-posterior and medio-lateral torque in standing. Our results suggest that the two heads of the gastrocnemius may operate in different ankle ranges with the larger MG being of primary importance when standing, likely due to its fascicle orientation. These differences in MU discharge behavior were independent of the type of descending neural drive, which points to a muscle-specific optimization of triceps surae motoneurons.

  7. Absence of lateral gastrocnemius activity and differential motor unit behavior in soleus and medial gastrocnemius during standing balance

    PubMed Central

    Héroux, Martin E.; Dakin, Christopher J.; Luu, Billy L.; Inglis, John Timothy

    2013-01-01

    In a standing position, the vertical projection of the center of mass passes in front of the ankle, which requires active plantar-flexor torque from the triceps surae to maintain balance. We recorded motor unit (MU) activity in the medial (MG) and lateral (LG) gastrocnemius muscle and the soleus (SOL) in standing balance and voluntary isometric contractions to understand the effect of functional requirements and descending drive from different neural sources on motoneuron behavior. Single MU activity was recorded in seven subjects with wire electrodes in the triceps surae. Two 3-min standing balance trials and several ramp-and-hold contractions were performed. Lateral gastrocnemius MU activity was rarely observed in standing. The lowest thresholds for LG MUs in ramp contractions were 20–35 times higher than SOL and MG MUs (P < 0.001). Compared with MUs from the SOL, MG MUs were intermittently active (P < 0.001), had higher recruitment thresholds (P = 0.022), and greater firing rate variability (P < 0.001); this difference in firing rate variability was present in standing balance and isometric contractions. In SOL and MG MUs, both recruitment of new MUs (R2 = 0.59–0.79, P < 0.01) and MU firing rates (R2 = 0.05–0.40, P < 0.05) were associated with anterior-posterior and medio-lateral torque in standing. Our results suggest that the two heads of the gastrocnemius may operate in different ankle ranges with the larger MG being of primary importance when standing, likely due to its fascicle orientation. These differences in MU discharge behavior were independent of the type of descending neural drive, which points to a muscle-specific optimization of triceps surae motoneurons. PMID:24311748

  8. Differential Contribution of Kainate Receptors to EPSCs in Superficial Layer Neurons of the Rat Medial Entorhinal Cortex

    PubMed Central

    West, Peter J.; Dalpé-Charron, Alexandre; Wilcox, Karen S.

    2009-01-01

    Although in situ hybridization studies have revealed the presence of kainate receptor (KAR) mRNA in neurons of the rat medial entorhinal cortex (mEC), the functional presence and roles of these receptors are only beginning to be examined. To address this deficiency, whole cell voltage clamp recordings of locally evoked EPSCs were made from mEC layer II and III neurons in combined entorhinal cortex -hippocampal brain slices. Three types of neurons were identified by their electroresponsive membrane properties, locations, and morphologies: stellate-like “Sag” neurons in layer II (S), pyramidal-like “No Sag” neurons in layer III (NS), and “Intermediate Sag” neurons with varied morphologies and locations (IS). Non-NMDA EPSCs in these neurons were composed of two components, and the slow decay component in NS neurons had larger amplitudes and contributed more to the combined EPSC than did those observed in S and IS neurons. This slow component was mediated by KARs and was characterized by its resistance to either GYKI 52466 (100 μM) or NBQX (1 μM), relatively slow decay kinetics, and sensitivity to CNQX (10–50 μM). KAR mediated EPSCs in pyramidal-like NS neurons contributed significantly more to the combined non-NMDA EPSC than did those from S and IS neurons. Layer III neurons of the mEC are selectively susceptible to degeneration in human temporal lobe epilepsy (TLE) and animal models of TLE such as kainate-induced status epilepticus. Characterizing differences in the complement of postsynaptic receptors expressed in injury prone versus injury resistant mEC neurons represents an important step toward understanding the vulnerability of layer III neurons seen in TLE. PMID:17395391

  9. New Complication Associated With All-Inside Meniscal Repair Device

    PubMed Central

    Warth, Lucian C.; Bollier, Matthew J.; Hoffman, Douglas F.; Cummins, Justin S.; Hall, Mederic M.

    2016-01-01

    Background: The importance of meniscal preservation has become widely accepted, and meniscal repair techniques have evolved over recent years. With new techniques come new complications, which are critical to recognize. Purpose: To describe a new complication of foreign body reaction from a nonabsorbable suture anchor associated with improper placement of the all-inside meniscal device. Study Design: Case series; Level of evidence, 4. Methods: This study was a retrospective review of 3 patients who developed pain associated with a foreign body reaction from a misplaced all-inside meniscal device. Results: All patients had a delayed diagnosis (6 months to 8 years) and negative magnetic resonance imaging (MRI). Diagnostic ultrasound identified the misplaced suture with foreign body reaction and was used to guide a diagnostic injection of local anesthetic prior to surgical intervention. Intraoperative ultrasound guidance was utilized to precisely localize and excise the suture material and associated reactive tissue. Conclusion: Foreign body reaction from a misplaced all-inside meniscal device is a previously unreported complication. Diagnosis is challenging as MRI and arthroscopy can be unrevealing. Diagnostic ultrasound was able to identify the foreign body reaction, confirm the diagnosis by facilitating diagnostic local anesthetic injection, and guide surgical excision. Sonographic evaluation should be considered in patients presenting with ongoing knee pain after all-inside meniscus repair. PMID:27635413

  10. Meniscal Transplants and Scaffolds: A Systematic Review of the Literature

    PubMed Central

    Dangelmajer, Sean; Familiari, Filippo; Simonetta, Roberto; Kaymakoglu, Mehmet; Huri, Gazi

    2017-01-01

    The reported incidence of meniscal tears is approximately 61 per 100,000. In instances where preservation of the native meniscus is no longer a feasible option, meniscal allograft transplantation (MAT) and implants or scaffolds may be considered. The goal of this review was to compare the success and failure rates of two techniques, MAT and meniscal scaffolds, and make an inference which treatment is more preferable at the present time and future. Studies that met inclusion criteria were assessed for technique used, type of transplant used, number of procedures included in the study, mean age of patients, mean follow-up time, number of failures, failure rate, and reported reoperation rate. Fifteen studies for the MAT group and 7 studies for the meniscal scaffold group were identified. In this selection of studies, the average failure rate in the MAT group was 18.7% and average reoperation rate was 31.3%. The average failure rate in the meniscal scaffold group was 5.6%, and average reoperation rate was 6.9%. It appears that although MAT is associated with high reoperation and failure rates, the limited number of studies on both MAT and scaffolds and mainly short-term results of scaffold studies make it difficult to make an objective comparison. PMID:28231642

  11. 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

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

    PubMed

    Kurzweil, Peter R; Kelley, Steven T

    2006-06-01

    The medial side is one of the most commonly injured areas of the knee. The anatomy, diagnosis, and treatment of medial collateral ligament and posteromedial corner (PMC) injuries can be challenging. Understanding the mechanism of injury and performing a thorough physical examination and radiographic evaluation is essential. Frequently, there are concomitant meniscal and other ligament injuries associated with medial-side injuries. Correct identification of all injured structures is important, as missed diagnoses can lead to significant disability. Unrecognized PMC injuries have been implicated in anteromedial rotary instability and failed anterior cruciate ligament reconstructions. Valgus stress testing is the cornerstone for the identification of medial-side knee injuries. Coronal sequences from magnetic resonance imaging are the most useful tool to view the medial collateral ligament and posteromedial structures. Stress x-rays and ultrasound may also be helpful. Thorough physical examination and imaging of injuries to the PMC should dictate the appropriate treatment for optimal results.

  13. Differential Gene Expression in the Developing Lateral Geniculate Nucleus and Medial Geniculate Nucleus Reveals Novel Roles for Zic4 and Foxp2 in Visual and Auditory Pathway Development

    PubMed Central

    Horng, Sam; Kreiman, Gabriel; Ellsworth, Charlene; Page, Damon; Blank, Marissa; Millen, Kathleen; Sur, Mriganka

    2010-01-01

    Primary sensory nuclei of the thalamus process and relay parallel channels of sensory input into the cortex. The developmental processes by which these nuclei acquire distinct functional roles are not well understood. To identify novel groups of genes with a potential role in differentiating two adjacent sensory nuclei, we performed a microarray screen comparing perinatal gene expression in the principal auditory relay nucleus, the medial geniculate nucleus (MGN), and principal visual relay nucleus, the lateral geniculate nucleus (LGN). We discovered and confirmed groups of highly ranked, differentially expressed genes with qRT-PCR and in situ hybridization. A functional role for Zic4, a transcription factor highly enriched in the LGN, was investigated using Zic4-null mice, which were found to have changes in topographic patterning of retinogeniculate projections. Foxp2, a transcriptional repressor expressed strongly in the MGN, was found to be positively regulated by activity in the MGN. These findings identify roles for two differentially expressed genes, Zic4 and Foxp2, in visual and auditory pathway development. Finally, to test whether modality-specific patterns of gene expression are influenced by extrinsic patterns of input, we performed an additional microarray screen comparing the normal MGN to “rewired” MGN, in which normal auditory afferents are ablated and novel retinal inputs innervate the MGN. Data from this screen indicate that rewired MGN acquires some patterns of gene expression that are present in the developing LGN, including an upregulation of Zic4 expression, as well as novel patterns of expression which may represent unique processes of cross-modal plasticity. PMID:19864579

  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. Biological Knee Reconstruction With Concomitant Autologous Chondrocyte Implantation and Meniscal Allograft Transplantation

    PubMed Central

    Ogura, Takahiro; Bryant, Tim; Minas, Tom

    2016-01-01

    Background: Treating articular cartilage defects and meniscal deficiency is challenging. Although some short- to mid-term follow-up studies report good clinical outcomes after concurrent autologous chondrocyte implantation (ACI) and meniscal allograft transplantation (MAT), longer follow-up is needed. Purpose: To evaluate mid- to long-term outcomes after combined ACI with MAT. Study Design: Case series; Level of evidence, 4. Methods: We performed a retrospective review of prospectively gathered data from patients who had undergone ACI with MAT between 1999 and 2013. A single surgeon treated 18 patients for symptomatic full-thickness chondral defects with meniscal deficiency. One patient was lost to follow-up. Thus, 17 patients (18 knees; mean age, 31.7 years) were evaluated over a mean 7.9-year follow-up (range, 2-16 years). A mean 1.8 lesions per knee were treated over a total surface area of 7.6 cm2 (range, 2.3-21 cm2) per knee. Seventeen lateral and 1 medial MATs were performed. Survival was analyzed using the Kaplan-Meier method. The modified Cincinnati Knee Rating Scale, Western Ontario and McMaster Universities Osteoarthritis Index, visual analog scale, and Short Form–36 were used to evaluate clinical outcomes. Patients also self-reported knee function and satisfaction. Standard radiographs were scored for Kellgren-Lawrence (K-L) grade. Results: Both 5- and 10-year survival rates were 75%. Outcomes for 6 knees were considered failures. Of the 6 failures, 4 knees were converted to arthroplasty and the other 2 knees underwent biological revision surgery. Of the 12 successfully operated knees, all clinical measures significantly improved postoperatively. Ten patients representing 11 of the 12 knees rated outcomes for their knees as good or excellent, and 1 rated their outcome as fair. Eight patients representing 9 of the 12 knees were satisfied with the procedure. There was no significant osteoarthritis progression based on K-L grading from preoperatively to a

  16. The Oxford Medial Partial Knee Replacement. The rationale for a femur first technique.

    PubMed

    Shakespeare, David; Waite, Jon

    2012-12-01

    The Oxford Medial Partial Knee Replacement (PKR) has been in clinical use for more than 20 years. The current surgical technique requires a number of judgements to be made, and even in the most experienced hands surgery can be challenging. We present an alternative surgical technique, which we believe addresses the unpredictability of the current method. The technique is based on precise femoral positioning prior to tibial resection. A prospective series of 125 Oxford Medial PKRs was performed using this new technique and a radiographical analysis was performed. We used meniscal thickness, meniscal position and femoral position as measures of reproducibility of the procedure. Variability in meniscal thickness has been minimised with a 3mm meniscal bearing used in 21 knees (15%), 4mm (the target thickness) in 73 knees (59%) and 5mm in 30 knees (24%). The mean meniscal position relative to the tibial tray upright was 2mm (SD 1mm). Femoral component position relative to the tibial tray, which defines the excursion of the meniscus was also assessed. Mean coronal plane alignment was 2° of valgus (SD 2.8). Mean flexion/extension was 3.8° (SD 3.1). The mean rotation was 10° internal (SD 5°). We believe this new technique makes this procedure more reproducible, and should be considered as a viable alternative to the current recommended technique. It may be a better technique for those surgeons who are relatively inexperienced with this prosthesis. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. 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

  18. 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

  19. Arthroscopic outside-in meniscal repair through a needle hole.

    PubMed

    Laupattarakasem, Wiroon; Sumanont, Sermsak; Kesprayura, Suraphol; Kasemkijwattana, Channarong

    2004-07-01

    This article describes an alternative method for outside-in repair of a longitudinal meniscal tear through a needle hole, which will produce an almost negligible cutaneous scar. The procedure is performed under arthroscopic set-up using an 18-gauge needle preloaded with appropriate suture material. Insert the needle twice through the same cutaneous entry hole to form a mattress loop across the torn meniscal segments. The first insertion penetrates both segments and forms a loop. The second insertion then engages the outer segment and forms another loop. Draw the free end of this second loop into the joint and feed it into the first loop. Pull the first loop out from the joint together with the trapped portion near the free end, until the whole suture becomes a vertical mattress. Finally, tie a slipknot and several half hitches to close the meniscal gap under the stitch. In a large bucket-handle tear, stitches should be started at the middle and then alternating anteriorly and posteriorly 3 to 4 mm apart. To ensure that no significant extracapsular structures are trapped in each stitch, a 13-gauge needle can be used as a cannula sheath. This technique is economical and technically safe and simple for reparable meniscal lesions, including the posterior horn.

  20. Meniscal root tears: from basic science to ultimate surgery.

    PubMed

    Papalia, Rocco; Vasta, Sebastiano; Franceschi, Francesco; D'Adamio, Stefano; Maffulli, Nicola; Denaro, Vincenzo

    2013-01-01

    In meniscal root tears (MRTs), the disruption of collagen fibers that provide hoop strength results in extrusion of the menisci, altering their biomechanical properties. Clinical diagnosis is difficult, but magnetic resonance imaging usually allows to identify the lesion. Located into the vascularized zone of the meniscus, management is preferentially arthroscopic, aimed at repairing the lesions with arthroscopic transosseous sutures or suture anchors. PubMed, Cochrane Library, Google Scholar and Ovid Medline were searched in July 2012 to find literature on MRT tears. We reviewed the literature on biomechanics, imaging features and current treatments of these tears. Twenty-seven appropriate articles were identified and included in the study: 6 biomechanical studies, 11 imaging-based investigations for diagnosis, 1 study on clinical diagnosis and 9 studies about treatment. MRTs are infrequent, accounting for 10.1% of all arthroscopic meniscectomies. When the damage occurs to the roots, the transmission of the circumferential hoop tension is impaired and, consequently, the menisci tend to be displaced anteriorly and posteriorly, altering the biomechanics and possibly the kinematics of the knee. Although the importance of the integrity of the meniscal roots is well established, their diagnosis and treatment are still controversial. Biomechanical and clinical studies demonstrate that surgical repair of acute, traumatic meniscal root injuries fully restores the biomechanical features of the menisci, leading to pain relief and functional improvement. The current available surgical techniques for the meniscal root repair (suture anchors and pullout repair) are comparable. Level of evidence IV.

  1. Meniscal Transplantation and its Effect on Osteoarthritis Risk: an abridged protocol for the MeTEOR study: a comprehensive cohort study incorporating a pilot randomised controlled trial.

    PubMed

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

    2015-06-01

    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. 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. This study is expected to report its findings in 2016. Cite this article: Bone Joint Res 2015;4:93-8. ©2015 The British Editorial Society of Bone & Joint Surgery.

  2. 3D geometry analysis of the medial meniscus--a statistical shape modeling approach.

    PubMed

    Vrancken, A C T; Crijns, S P M; Ploegmakers, M J M; O'Kane, C; van Tienen, T G; Janssen, D; Buma, P; Verdonschot, N

    2014-10-01

    The geometry-dependent functioning of the meniscus indicates that detailed knowledge on 3D meniscus geometry and its inter-subject variation is essential to design well functioning anatomically shaped meniscus replacements. Therefore, the aim of this study was to quantify 3D meniscus geometry and to determine whether variation in medial meniscus geometry is size- or shape-driven. Also we performed a cluster analysis to identify distinct morphological groups of medial menisci and assessed whether meniscal geometry is gender-dependent. A statistical shape model was created, containing the meniscus geometries of 35 subjects (20 females, 15 males) that were obtained from MR images. A principal component analysis was performed to determine the most important modes of geometry variation and the characteristic changes per principal component were evaluated. Each meniscus from the original dataset was then reconstructed as a linear combination of principal components. This allowed the comparison of male and female menisci, and a cluster analysis to determine distinct morphological meniscus groups. Of the variation in medial meniscus geometry, 53.8% was found to be due to primarily size-related differences and 29.6% due to shape differences. Shape changes were most prominent in the cross-sectional plane, rather than in the transverse plane. Significant differences between male and female menisci were only found for principal component 1, which predominantly reflected size differences. The cluster analysis resulted in four clusters, yet these clusters represented two statistically different meniscal shapes, as differences between cluster 1, 2 and 4 were only present for principal component 1. This study illustrates that differences in meniscal geometry cannot be explained by scaling only, but that different meniscal shapes can be distinguished. Functional analysis, e.g. through finite element modeling, is required to assess whether these distinct shapes actually influence

  3. 3D geometry analysis of the medial meniscus – a statistical shape modeling approach

    PubMed Central

    Vrancken, A C T; Crijns, S P M; Ploegmakers, M J M; O'Kane, C; van Tienen, T G; Janssen, D; Buma, P; Verdonschot, N

    2014-01-01

    The geometry-dependent functioning of the meniscus indicates that detailed knowledge on 3D meniscus geometry and its inter-subject variation is essential to design well functioning anatomically shaped meniscus replacements. Therefore, the aim of this study was to quantify 3D meniscus geometry and to determine whether variation in medial meniscus geometry is size- or shape-driven. Also we performed a cluster analysis to identify distinct morphological groups of medial menisci and assessed whether meniscal geometry is gender-dependent. A statistical shape model was created, containing the meniscus geometries of 35 subjects (20 females, 15 males) that were obtained from MR images. A principal component analysis was performed to determine the most important modes of geometry variation and the characteristic changes per principal component were evaluated. Each meniscus from the original dataset was then reconstructed as a linear combination of principal components. This allowed the comparison of male and female menisci, and a cluster analysis to determine distinct morphological meniscus groups. Of the variation in medial meniscus geometry, 53.8% was found to be due to primarily size-related differences and 29.6% due to shape differences. Shape changes were most prominent in the cross-sectional plane, rather than in the transverse plane. Significant differences between male and female menisci were only found for principal component 1, which predominantly reflected size differences. The cluster analysis resulted in four clusters, yet these clusters represented two statistically different meniscal shapes, as differences between cluster 1, 2 and 4 were only present for principal component 1. This study illustrates that differences in meniscal geometry cannot be explained by scaling only, but that different meniscal shapes can be distinguished. Functional analysis, e.g. through finite element modeling, is required to assess whether these distinct shapes actually influence

  4. 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

  5. Three single loops enhance the biomechanical behavior of the transtibial pull-out technique for posterior meniscal root repair.

    PubMed

    Camarda, Lawrence; Pitarresi, Giuseppe; Lauria, Michele; Fazzari, Federico; D'Arienzo, Michele

    2017-07-03

    To investigate the effect of applying an additional suture to enhance the biomechanical behavior of the suture-meniscus construct used during the transtibial pull-out repair technique. A total of 20 fresh-frozen porcine tibiae with intact medial menisci were used. In one half of all specimens (N = 10), two non-absorbable sutures were passed directly over the meniscal root from the tibia side of the meniscus to the femoral side (2SS). In other ten specimens, three sutures were passed over the meniscal root (3SS). All specimens were subjected to cyclic loading followed by load-to-failure testing. Displacement of the construct was recorded at 100, 500, and 1000 cycles. Further, stiffness (500-1000 cycles) and ultimate load and modes of failure of the suture-meniscus construct were also recorded. There was no statistically significant difference between the Group 2SS and Group 3SS at the 1st (1.6 ± 0.7 vs 1.4 ± 0.4 mm) and the 100th cycle (2 ± 0.7 vs 1.8 ± 0.4 mm). At 500 and 1000 cycles, the 2SS fixation technique resulted in significantly more displacement than the 3SS fixation technique (2.8 ± 0.6 vs 2.3 ± 0.5 mm; 3.1 ± 0.7 vs 2.5 ± 0.5 mm) (p < 0.05). No differences between two groups were noted concerning ultimate load to failure and stiffness (500-1000 cycles). Three single sutures technique provided superior biomechanical properties compared with the two single sutures technique during the conducted fatigue tests. Applying three simple stitches during meniscal root repair might be beneficial for healing of the posterior meniscal root, potentially reducing the post-operative immobilization time.

  6. Differential involvement of prelimbic and infralimbic medial prefrontal cortex in discrete cue-induced reinstatement of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) seeking in rats.

    PubMed

    Ball, Kevin T; Slane, Mylissa

    2012-12-01

    The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) is a widely abused drug, particularly in adolescent and young adult populations. Although it was shown that MDMA-associated cues reinstate extinguished MDMA seeking in an animal relapse model, there is little information regarding the neural mechanisms underlying this behavior. Because the medial prefrontal cortex (mPFC) plays an important role in relapse to cocaine and methamphetamine seeking, we tested the effects of lidocaine inactivation of prelimbic (PL) and infralimbic (IL) subregions of mPFC on cue-induced relapse to MDMA seeking. Rats were trained to respond for MDMA infusions (0.50 mg/kg/infusion, i.v.) paired with a discrete cue in daily 2-h sessions. Responding was reinforced contingent on a modified fixed ratio 5 schedule of reinforcement. Cue-induced reinstatement tests were conducted after responding was extinguished in the absence of MDMA and the conditioned cues. Prior to reinstatement tests, rats received bilateral microinjections of either lidocaine (100 μg/0.5 μl/side) or physiological saline (0.5 μl/side) delivered to either PL or IL mPFC. Microinjections of lidocaine into PL completely blocked reinstatement of MDMA-seeking behavior compared with saline microinjections into the same region. Lidocaine microinjections did not, however, have an effect on food-maintained responding, ruling out a nonspecific disruption of motor performance. Conversely, lidocaine inactivation of IL had no effect on reinstatement of MDMA seeking or food-maintained responding. Our results provide direct support for PL activation in reinstatement of MDMA-seeking behavior. Moreover, akin to cocaine seeking, there appears to be differential involvement of PL and IL subregions in this behavior.

  7. Anatomical Knee Variants in Discoid Lateral Meniscal Tears

    PubMed Central

    Chen, Xu-Xu; Li, Jian; Wang, Tao; Zhao, Yang; Kang, Hui

    2017-01-01

    Background: Discoid lateral meniscus was a common meniscal dysplasia and was predisposed to tear. There were some anatomical knee variants in patients with discoid lateral meniscus. The aim of this study was to analyze the relationship between anatomical knee variants and discoid lateral meniscal tears. Methods: There were totally 125 cases of discoid lateral meniscus enrolled in this study from February 2008 to December 2013. Eighty-seven patients who underwent arthroscopic surgery for right torn discoid lateral meniscus were enrolled in the torn group. An additional 38 patients who were incidentally identified as having intact discoid lateral menisci on magnetic resonance imaging (MRI) findings were included in the control group. All patients were evaluated for anatomical knee variants on plain radiographs, including lateral joint space distance, height of the lateral tibial spine, height of the fibular head, obliquity of the lateral tibial plateau, squaring of the lateral femoral condyle, cupping of the lateral tibial plateau, lateral femoral condylar notch, and condylar cutoff sign. The relationship between anatomical variants and meniscal tear was evaluated. These anatomical variants in cases with complete discoid meniscus were also compared with those in cases with incomplete discoid meniscus. Results: There were no significant differences between the two groups in lateral joint space distance (P = 0.528), height of the lateral tibial spine (P = 0.927), height of the fibular head (P = 0.684), obliquity of the lateral tibial plateau (P = 0.672), and the positive rates of squaring of the lateral femoral condyle (P = 0.665), cupping of the lateral tibial plateau (P = 0.239), and lateral femoral condylar notch (P = 0.624). The condylar cutoff sign was significantly different between the two groups, with the prominence ratio in the torn group being smaller than that in the control group (0.74 ± 0.11 vs. 0.81 ± 0.04, P = 0.049). With the decision value of the

  8. Selective serotonin receptor stimulation of the medial nucleus accumbens differentially affects appetitive motivation for food on a progressive ratio schedule of reinforcement.

    PubMed

    Pratt, Wayne E; Schall, Megan A; Choi, Eugene

    2012-03-09

    Previously, we reported that stimulation of selective serotonin (5-HT) receptor subtypes in the nucleus accumbens shell differentially affected consumption of freely available food. Specifically, activation of 5-HT(6) receptors caused a dose-dependent increase in food intake, while the stimulation of 5-HT(1/7) receptor subtypes decreased feeding [34]. The current experiments tested whether similar pharmacological activation of nucleus accumbens serotonin receptors would also affect appetitive motivation, as measured by the amount of effort non-deprived rats exerted to earn sugar reinforcement. Rats were trained to lever press for sugar pellets on a progressive ratio 2 schedule of reinforcement. Across multiple treatment days, three separate groups (N=8-10) received bilateral infusions of the 5-HT(6) agonist EMD 386088 (at 0.0, 1.0 and 4.0 μg/0.5 μl/side), the 5-HT(1/7) agonist 5-CT (at 0, 0.5, 1.0, or 4.0 μg/0.5 μl/side), or the 5-HT(2C) agonist RO 60-0175 fumarate (at 0, 2.0, or 5.0 μg/0.5 μl/side) into the anterior medial nucleus accumbens prior to a 1-h progressive ratio session. Stimulation of 5-HT(6) receptors caused a dose-dependent increase in motivation as assessed by break point, reinforcers earned, and total active lever presses. Stimulation of 5-HT(1/7) receptors increased lever pressing at the 0.5 μg dose of 5-CT, but inhibited lever presses and break point at 4.0 μg/side. Injection of the 5-HT(2C) agonist had no effect on motivation within the task. Collectively, these experiments suggest that, in addition to their role in modulating food consumption, nucleus accumbens 5-HT(6) and 5-HT(1/7) receptors also differentially regulate the appetitive components of food-directed motivation.

  9. Selective serotonin receptor stimulation of the medial nucleus accumbens differentially affects appetitive motivation for food on a progressive ratio schedule of reinforcement

    PubMed Central

    Pratt, Wayne E.; Schall, Megan A.; Choi, Eugene

    2012-01-01

    Previously, we reported that stimulation of selective serotonin (5-HT) receptor subtypes in the nucleus accumbens shell differentially affected consumption of freely available food. Specifically, activation of 5-HT6 receptors caused a dose-dependent increase in food intake, while the stimulation of 5-HT1/7 receptor subtypes decreased feeding [34]. The current experiments tested whether similar pharmacological activation of nucleus accumbens serotonin receptors would also affect appetitive motivation, as measured by the amount of effort non-deprived rats exerted to earn sugar reinforcement. Rats were trained to lever press for sugar pellets on a progressive ratio 2 schedule of reinforcement. Across multiple treatment days, three separate groups (N = 8–10) received bilateral infusions of the 5-HT6 agonist EMD 386088 (at 0.0, 1.0 and 4.0 μg/0.5 μl/side), the 5-HT1/7 agonist 5-CT (at 0, 0.5, 1.0, or 4.0 μg/0.5 μl/side), or the 5-HT2C agonist RO 60-0175 fumarate (at 0, 2.0, or 5.0 μg/0.5 μl/side) into the anterior medial nucleus accumbens prior to a 1-hr progressive ratio session. Stimulation of 5-HT6 receptors caused a dose-dependent increase in motivation as assessed by break point, reinforcers earned, and total active lever presses. Stimulation of 5-HT1/7 receptors increased lever pressing at the 0.5 μg dose of 5-CT, but inhibited lever presses and break point at 4.0 μg/side. Injection of the 5- HT2C agonist had no effect on motivation within the task. Collectively, these experiments suggest that, in addition to their role in modulating food consumption, nucleus accumbens 5-HT6 and 5-HT1/7 receptors also differentially regulate the appetitive components of food-directed motivation. PMID:22306095

  10. The relation between chondromalacia patella and meniscal tear and the sulcus angle/ trochlear depth ratio as a powerful predictor.

    PubMed

    Resorlu, Hatice; Zateri, Coskun; Nusran, Gurdal; Goksel, Ferdi; Aylanc, Nilufer

    2017-01-01

    To investigate the relation between chondromalacia patella and the sulcus angle/trochlear depth ratio as a marker of trochlear morphology. In addition, we also planned to show the relationship between meniscus damage, subcutaneous adipose tissue thickness as a marker of obesity, patellar tilt angle and chondromalacia patella. Patients with trauma, rheumatologic disease, a history of knee surgery and patellar variations such as patella alba and patella baja were excluded. Magnetic resonance images of the knees of 200 patients were evaluated. Trochlear morphology from standardized levels, patellar tilt angle, lateral/medial facet ratio, subcutaneous adipose tissue thickness from 3 locations and meniscus injury were assessed by two specialist radiologists. Retropatellar cartilage was normal in 108 patients (54%) at radiological evaluation, while chondromalacia patella was determined in 92 (46%) cases. Trochlear sulcus angle and prepatellar subcutaneous adipose tissue thickness were significantly high in patients with chondromalacia patella, while trochlear depth and lateral patellar tilt angle were low. The trochlear sulcus angle/trochlear depth ratio was also high in chondromalacia patella and was identified as an independent risk factor at regression analysis. Additionally, medial meniscal tear was observed in 35 patients (38%) in the chondromalacia patella group and in 27 patients (25%) in the normal group, the difference being statistically significant (P = 0.033). An increased trochlear sulcus angle/trochlear depth ratio is a significant predictor of chondromalacia patella. Medial meniscus injury is more prevalent in patients with chondromalacia patella in association with impairment in knee biomechanics and the degenerative process.

  11. 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.

  12. Understanding the different physical examination tests for suspected meniscal tears.

    PubMed

    Shrier, Ian; Boudier-Revéret, Mathieu; Fahmy, Kamal

    2010-01-01

    Meniscal tears are common in sport medicine practice. Many articles and textbooks discuss the relative validity of the different components of the physical examination with respect to their sensitivity, specificity, and positive/negative predictive values as if they were diagnostic tests. In this article, we demonstrate why this approach is limited, including the heterogeneous nature of meniscal tear pathology (e.g., posterior vs anterior). Therefore, in this article, we categorize all the published tests in the literature with regards to the mechanism underlying a positive test. We believe our approach provides the clinician with additional tools to diagnose tears. Future research should explore predictive models based on the different components accounting for heterogeneous pathology and different patient contexts.

  13. Future directions. Collagen-based prostheses for meniscal regeneration.

    PubMed

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

    1990-03-01

    Prosthetic meniscal replacement offers the ability to stabilize the meniscectomized knee and provide prophylaxis against early degenerative arthritis. Since prosthetic meniscal replacement may be performed in the setting of normal articular cartilage, a prosthesis will be required to match the exact joint configuration, induce the same lubricity, produce the same coefficient of friction, and absorb and dampen the same joint forces (without incurring significant creep or abrasion) as does the normal meniscus. This feat is currently beyond the capabilities of artificial materials alone. Alternatively, collagen-based prostheses acting as resorbable regeneration templates offer the possibility of inducing regrowth of new menisci. This paper presents a summary of hypotheses, considerations, and laboratory evidence for the use of collagen-based, resorbable matrices as regeneration templates.

  14. Radiographic identification of the anterior and posterior root attachments of the medial and lateral menisci.

    PubMed

    James, Evan W; LaPrade, Christopher M; Ellman, Michael B; Wijdicks, Coen A; Engebretsen, Lars; LaPrade, Robert F

    2014-11-01

    Anatomic root placement is necessary to restore native meniscal function during meniscal root repair. Radiographic guidelines for anatomic root placement are essential to improve the accuracy and consistency of anatomic root repair and to optimize outcomes after surgery. To define quantitative radiographic guidelines for identification of the anterior and posterior root attachments of the medial and lateral menisci on anteroposterior (AP) and lateral radiographic views. Descriptive laboratory study. The anterior and posterior roots of the medial and lateral menisci were identified in 12 human cadaveric specimens (average age, 51.3 years; age range, 39-65 years) and labeled using 2-mm radiopaque spheres. True AP and lateral radiographs were obtained, and 2 raters independently measured blinded radiographs in relation to pertinent landmarks and radiographic reference lines. On AP radiographs, the anteromedial and posteromedial roots were, on average, 31.9 ± 5.0 mm and 36.3 ± 3.5 mm lateral to the edge of the medial tibial plateau, respectively. The anterolateral and posterolateral roots were, on average, 37.9 ± 5.2 mm and 39.3 ± 3.8 mm medial to the edge of the lateral tibial plateau, respectively. On lateral radiographs, the anteromedial and anterolateral roots were, on average, 4.8 ± 3.7 mm and 20.5 ± 4.3 mm posterior to the anterior margin of the tibial plateau, respectively. The posteromedial and posterolateral roots were, on average, 18.0 ± 2.8 mm and 19.8 ± 3.5 mm anterior to the posterior margin of the tibial plateau, respectively. The intrarater and interrater intraclass correlation coefficients (ICCs) were >0.958, demonstrating excellent reliability. The meniscal root attachment sites were quantitatively and reproducibly defined with respect to anatomic landmarks and superimposed radiographic reference lines. The high ICCs indicate that the measured radiographic relationships are a consistent means for evaluating meniscal root positions. This study

  15. Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells

    DTIC Science & Technology

    2016-09-01

    understanding of the molecular and cellular events that underlie tissue repair is essential for addressing pathologies associated with injury, disease and...aging in the musculoskeletal system. Little information exists about resident stem cell populations in the mouse meniscus, a model increasingly used to...for meniscal pathologies . Analysis of meniscus derived-stem cells in an animal model such as the mouse will allow for detailed studies of their

  16. 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

  17. Articular cartilage scores in cranial cruciate ligament-deficient dogs with or without bucket handle tears of the medial meniscus.

    PubMed

    Kaufman, Kathryn; Beale, Brian S; Thames, Howard D; Saunders, W Brian

    2017-01-01

    To compare articular cartilage scores in cranial cruciate ligament (CCL)-deficient dogs with or without concurrent bucket handle tears (BHT) of the medial meniscus. Retrospective case series. Client-owned dogs treated with arthroscopy and tibial plateau leveling osteotomy or extracapsular repair for complete CCL rupture (290 stifles from 264 dogs). Medical records and arthroscopic images were reviewed. Medial femoral condyle (MFC) and medial tibial plateau (MTP) cartilage was scored using the modified Outerbridge scale. Periarticular osteophytosis (PAO) and injury to the medial meniscus were recorded. Data were analyzed using Student's t-tests, Wilcoxon rank-sum test, and Fisher's exact test for changes in the stifle based on meniscal condition, body weight, and duration of lameness. PAO, MFC, and MTP articular cartilage scores were not significantly different in dogs with or without BHT. There were no significant differences in MFC or MTP scores when dogs were evaluated based on bodyweight and the presence or absence of a BHT. However, PAO formation was significantly increased in dogs weighing >13.6 kg and concurrent meniscal injury vs. dogs weighing <13.6 kg and concurrent meniscal injury (P < .001). Significantly more stifles with chronic lameness (40 of 89; 44.9%) had the highest PAO score of 2 reported compared to only 42 of 182 stifles (23.1%) with acute lameness (P < .001). The presence of a BHT of the medial meniscus was not associated with more severe arthroscopic articular cartilage lesions in the medial joint compartment at the time of surgery. © 2016 The American College of Veterinary Surgeons.

  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. 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…

  20. 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…

  1. 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…

  2. Return to Sports After Athletes Undergo Meniscal Surgery: A Systematic Review.

    PubMed

    Lee, Yong Seuk; Lee, O-Sung; Lee, Seung Hoon

    2017-10-05

    The aim of this systematic review was to determine the time to and rate of the return to sports (RTS) after meniscal surgery and to compare these values among the different types of meniscal surgeries. Systematic review. The MEDLINE, EMBASE, and Cochrane databases were searched. Studies that met the following criteria were included: (1) English article, (2) full-text available, (3) study on athletes, and (4) primary outcome is RTS after meniscal surgery, such as meniscectomy, meniscal repair, and meniscal allograft transplantation (MAT). Eleven articles were included in the final analysis. Most players returned to the preinjury activity level from 7 to 9 weeks after partial meniscectomy. After meniscal repair, 81% to 88.9% of athletes returned to sports. The time to RTS after isolated meniscal repair was on average 5.6 months, and the time to RTS was longer for athletes who required concurrent anterior cruciate ligament reconstruction (ACLR). After MAT, 67% to 85.7% of athletes returned to sports, and the time to RTS ranged from 7.6 to 16.5 months. The shortest time to RTS and the highest RTS rate were observed after partial meniscectomy. The time to RTS was shorter, and the RTS rate was higher after meniscal repair than after MAT. Concurrent procedures such as ACLR prolonged the time to RTS, but it had no effect on the RTS rate and the level of sports activity at the time of RTS.

  3. Serotonin 5-HT1A and 5-HT2/1C receptors in the midbrain periaqueductal gray differentially modulate defensive rage behavior elicited from the medial hypothalamus of the cat.

    PubMed

    Shaikh, M B; De Lanerolle, N C; Siegel, A

    1997-08-15

    evidence that activation of 5-HT1A and 5-HT2/1C receptors within the midbrain PAG differentially modulate the expression of defensive rage behavior elicited from the medial hypothalamus of the cat.

  4. Impact of disease treatments on the progression of knee osteoarthritis structural changes related to meniscal extrusion: Data from the OAI progression cohort.

    PubMed

    Roubille, Camille; Martel-Pelletier, Johanne; Abram, François; Dorais, Marc; Delorme, Philippe; Raynauld, Jean-Pierre; Pelletier, Jean-Pierre

    2015-12-01

    In the perspective of personalized management of osteoarthritis (OA), a clinically relevant concern is the impact of meniscal extrusion (Ext) on response to treatment. This study aimed at determining the effects of conventional OA pharmacological treatments and those of the combination of glucosamine and chondroitin sulfate (Glu/CS) on knee structural changes in the presence or absence of Ext, using data from the progression cohort of the Osteoarthritis Initiative. In this longitudinal study, knee OA participants were stratified based on whether (+) or not (-) they received analgesics/NSAIDs (+ and -analgesics/NSAIDs) and/or Glu/CS (+ and -Glu/CS) for 24 consecutive months and on the presence (Ext+) or absence (Ext-) of medial meniscal extrusion at baseline. The main outcomes were knee structural changes including the loss of joint space width (JSW) and cartilage volume loss measured by quantitative MRI. In both - and +analgesics/NSAIDs groups (n = 300 each), the Ext+ participants had more-advanced disease at baseline (T0) and more JSW loss and cartilage volume loss in the medial compartment (p ≤ 0.003, univariate; p ≤ 0.049, multivariate analyses) at both 12 (T12) and 24 (T24) months compared to Ext- participants. In the -analgesics/NSAIDs group, Ext+ participants taking Glu/CS had significantly less cartilage volume loss in the medial plateau at T24 (p ≤ 0.010, univariate and multivariate analyses). In the +analgesics/NSAIDs group at T24, Ext- participants taking Glu/CS had less cartilage volume loss in the global (p ≤ 0.002, univariate and multivariate analyses) and medial and lateral plateaus (p = 0.034 and p = 0.013, respectively, multivariate analysis). No significant difference in JSW loss was found between the groups. This study is the first to demonstrate, using qMRI, that meniscal extrusion can modify the response to Glu/CS treatment in knee OA patients, depending on the severity of the disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Arthroscopic meniscal suture with the "double-loop technique".

    PubMed

    Wageck, J M; Rockett, P R

    1997-02-01

    A new personal technique of arthroscopic meniscal suture in which the knots are all inside the knees, fixed only in the meniscus is presented. Using a new tool, a flexible double-loop allows the suture in the posterior horn of the meniscus to pass the suture from the anterior portal to the posterior portal without the necessity of large posterior incision to protect the vascular-nervous plexus. This paper presents the indication and the technique, as well as a variety of possible knots and their advantages.

  6. Endoscopic Resection of Medial Extra-articular Cysts of the Knee.

    PubMed

    Lui, Tun Hing

    2017-04-01

    Although most of the parameniscal cysts are very small and asymptomatic, some of them can present with a painful mass or snapping knee. Because parameniscal cysts are almost always associated with horizontal meniscal tears, arthroscopic partial meniscectomy of the involved part of meniscus and intra-articular cyst drainage has become the most accepted procedure. However, arthroscopic cyst decompression through partial meniscectomy to the meniscocapsular junction to expose the communication between the cyst and the knee joint may sacrifice some of the healthy parts of the meniscus especially when meniscal tear is peripheral. Moreover, internal drainage may not be an adequate treatment for a cyst larger than 5 cm in size or a multiloculated cyst. The excision of the cyst is a more appropriate treatment option in these situations. The purpose of this Technical Note is to describe the details of endoscopic resection of medial extra-articular cysts of the knee. This technique is indicated in symptomatic medial extra-articular cysts of the knee with peripheral or no tear of the medial meniscus, especially if the cysts are large and multiloculated.

  7. Biomechanical and immunohistochemical properties of meniscal cartilage after high hydrostatic pressure treatment.

    PubMed

    Naal, Florian D; Schauwecker, Johannes; Steinhauser, Erwin; Milz, Stefan; von Knoch, Fabian; Mittelmeier, Wolfram; Diehl, Peter

    2008-10-01

    Meniscal allograft processing procedures, in particular gamma irradiation, deteriorate the biomechanical and biological properties of the transplanted tissue. High hydrostatic pressure (HHP) treatment, widely used in food technology to inactivate microorganisms while preserving natural compounds, might serve as a gentle alternative to gamma irradiation in the processing of meniscal allografts. We therefore investigated the effects of HHP treatment on the biomechanical and immunohistochemical properties of meniscal cartilage. Specimens of bovine menisci were treated with HHP for 10 min (20 degrees C) at 300 MPa and 600 MPa. Untreated control samples were left at room temperature and ambient pressure. We performed repetitive cycling indentation-tests to assess the biomechanical properties-in particular the viscoelastic behavior-of HHP treated and untreated meniscal specimens. Immunohistochemical analysis for collagens type I, II, and III and for the proteoglycans versican, aggrecan and for link-protein was performed by immunolabeling cross-sections of untreated and at 600 MPa HHP treated specimens. Comparing untreated and HHP treated meniscal specimens there were no significant differences for all tested biomechanical parameters. All cross-sections of untreated and HHP treated specimens stained positive for the collagens and proteoglycans. We demonstrated that meniscal cartilage can be treated by HHP at levels as high as 600 MPa without affection of the biomechanical and immunochistochemical properties. Therefore, HHP treatment might serve as a gentle alternative to gamma irradiation in the processing of meniscal allografts. Further research is necessary to verificate the present results in vivo. (c) 2008 Wiley Periodicals, Inc.

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

    PubMed Central

    Kise, Nina Jullum; 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 supervised

  9. Scaffolds for partial meniscal replacement: an updated systematic review.

    PubMed

    Papalia, Rocco; Franceschi, Francesco; Diaz Balzani, Lorenzo; D'Adamio, Stefano; Maffulli, Nicola; Denaro, Vincenzo

    2013-01-01

    Meniscectomy, a most common orthopaedic procedure, results in increased contact area of the articular surfaces of tibia and femur leading to early osteoarthritis. We systematically review the literature on clinical outcomes following partial meniscal replacement using different scaffolds. We performed a comprehensive search of Medline, CINAHL, Embase and the Cochrane Central Registry of Controlled Trials. The reference lists of the selected articles were then examined by hand. Only studies focusing on investigation of clinical outcomes on patients undergoing a partial meniscal replacement using a scaffold were selected. We then evaluated the methodological quality of each article using the Coleman methodology score (CMS), a 10 criteria scoring list assessing the methodological quality of the selected studies (CMS). Fifteen studies were included, all prospective studies, but only 2 were randomized controlled trials. Biological scaffolds were involved in 12 studies, 2 studies investigated synthetic scaffolds, whereas 1 remaining article presented data from the use of both classes of device. The mean modified CMS was 64.6. Several demographic and biomechanical factors could influence the outcomes of this treatment modality. Partial replacement using both classes of scaffolds achieves significant and encouraging improved clinical results when compared with baseline values or with controls when present, without no adverse reaction related to the device. There is a need for more and better designed randomized trials, to confirm with a stronger level of evidence the promising preliminary results achieved by the current research.

  10. 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

  11. Quantitative Magnetic Resonance Imaging Detects Changes in Meniscal Volume in Vivo After Partial Meniscectomy

    PubMed Central

    Bowers, Megan E.; Tung, Glenn A.; Oksendahl, Heidi L.; Hulstyn, Michael J.; Fadale, Paul D.; Machan, Jason T.; Fleming, Braden C.

    2010-01-01

    Background Quantifying changes in meniscal volume in vivo before and after partial meniscectomy (PM) could help elucidate the mechanisms involved in osteoarthritis development after meniscal injury and its surgical treatment. Purpose/Hypothesis To determine whether quantitative MRI (qMRI) could detect the immediate reduction in meniscal volume created by PM, while ruling out changes in unresected structures. We hypothesized that qMRI would be reliable for determining meniscal volume within the repeated images of unresected menisci. Additionally, we expected no significant difference in volume between the uninjured menisci of the injured knees and the same menisci of the uninjured knees. Study Design Controlled laboratory study. Methods Ten subjects with meniscal tears were evaluated with 3T MRI before and after arthroscopic PM. Manual segmentation was used to create models of the menisci and to determine the pre- and post-operative meniscal volumes for each subject. The responsiveness and reliability of qMRI for determining meniscal volume in vivo were evaluated using these measurements. We expected a decrease in volume of the resected menisci, but not in the uninjured menisci, after surgery. Results The mean pre-operative volume of the injured menisci was significantly greater than the mean post-operative volume (2896±277mm3 vs. 2480±277mm3; p=0.000). There was no significant difference between the mean pre- and post-operative volumes of the uninjured menisci (2687±256mm3 vs. 2694±256mm3; p=1.000). Conclusions Manual segmentation demonstrated a significant reduction in the volume of the surgically resected menisci after PM, but no significant change in the volume of unresected meniscal tissue, indicating that the manual segmentation method is responsive. Clinical Relevance This approach offers a novel, reliable method to study the relationship between the volume of meniscal tissue removed during PM and subsequent patient outcomes during long-term clinical

  12. Quantitative magnetic resonance imaging detects changes in meniscal volume in vivo after partial meniscectomy.

    PubMed

    Bowers, Megan E; Tung, Glenn A; Oksendahl, Heidi L; Hulstyn, Michael J; Fadale, Paul D; Machan, Jason T; Fleming, Braden C

    2010-08-01

    Quantifying changes in meniscal volume in vivo before and after partial meniscectomy (PM) could help elucidate the mechanisms involved in osteoarthritis development after meniscal injury and its surgical treatment. Purpose/ To determine whether quantitative magnetic resonance imaging (qMRI) can detect the immediate reduction in meniscal volume created by PM, while ruling out changes in unresected structures. We hypothesized that qMRI would be reliable for determining meniscal volume within the repeated images of unresected menisci. Additionally, we expected no significant difference in volume between the uninjured menisci of the injured knees and the same menisci of the uninjured knees. Cohort study (Diagnosis); Level of evidence, 2. Ten subjects with meniscal tears were evaluated with 3-T MRI before and after arthroscopic PM. Manual segmentation was used to create models of the menisci and to determine the preoperative and postoperative meniscal volumes for each subject. The responsiveness and reliability of qMRI for determining meniscal volume in vivo were evaluated using these measurements. We expected a decrease in volume of the resected menisci, but not in the uninjured menisci, after surgery. The mean preoperative volume of the injured menisci was significantly greater than the mean postoperative volume (2896 +/- 277 vs 2480 +/- 277 mm(3); P = .000). There was no significant difference between the mean preoperative and postoperative volumes of the uninjured menisci (2687 +/- 256 vs 2694 +/- 256 mm(3); P = 1.000). Manual segmentation demonstrated a significant reduction in the volume of the surgically resected menisci after PM, but no significant change in the volume of unresected meniscal tissue, indicating that the manual segmentation method is responsive. This approach offers a novel, reliable method to study the relationship between the volume of meniscal tissue removed during PM and subsequent patient outcomes during long-term clinical studies.

  13. Medial Collateral Ligament (MCL) Injuries

    MedlinePlus

    ... of Healthy Breakfasts Shyness Medial Collateral Ligament (MCL) Injuries KidsHealth > For Teens > Medial Collateral Ligament (MCL) Injuries ... Treatment Coping With an MCL Injury About MCL Injuries A torn medial collateral ligament (MCL) is a ...

  14. Medial canthal support structures: the medial retinaculum: a review.

    PubMed

    Kang, Hyera; Takahashi, Yasuhiro; Nakano, Takashi; Asamoto, Ken; Ikeda, Hiroshi; Kakizaki, Hirohiko

    2015-04-01

    The medial canthus is supported by several structures with a complicated 3-dimensional arrangement in a narrow space. Although the medial canthal tendon occupies a major portion of the area, the medial canthal support structures include the following entities: Horner's muscle, the medial rectus capsulopalpebral fascia including the medial check ligament, the medial horn of the levator aponeurosis, the medial horn supporting ligament, the medial horn of the lower eyelid retractors, the preseptal part of the orbicularis oculi muscle, and 3 variations of the Lockwood's ligament. We named the composite of these structures the "medial retinaculum," which is similar to the "lateral retinaculum" of the lateral canthus. Profound comprehension and consideration of the medial retinaculum warrants safe and effective surgery in the medial canthal region.

  15. Relationship between years in the trade and the development of radiographic knee osteoarthritis and MRI-detected meniscal tears and bursitis in floor layers. A cross-sectional study of a historical cohort

    PubMed Central

    Rytter, Søren; Marott, Jacob Louis; Bonde, Jens Peter

    2012-01-01

    Objectives An increased risk of developing knee disorders including radiographic knee osteoarthritis (OA) have been shown among workers with kneeling working demands. There may also be a dose-related association between duration of employment in occupations with kneeling work and development of radiographic knee OA and magnetic resonance imaging (MRI)-detected meniscal tears and bursitis. Design A cross-sectional study of a historical cohort. Setting Members of the trade unions for floor layers and graphic designers in Denmark. Participants 92 male floor layers and 49 graphic designers aged 36–70 years were randomly selected among participants from a clinical and radiographic study of 156 floor layers and 152 graphic designers. Outcome measures Radiographic tibiofemoral (TF) and patellofemoral (PF) knee-OA and MRI-detected meniscal tears and bursitis. Results were adjusted for age, earlier knee traumas, sports activities and body mass index in logistic regression models. Association between TF OA and years in the floor-laying trade was graphically examined by a restricted cubic spline with four knots. Results Increase in number of years with exposure to kneeling work is associated with radiographic TF knee OA with ORs 0.7, 95% CI 0.07 to 4.42; OR 1.89, 95% CI 0.29 to 12.3; OR 4.82, 95% CI 1.38 to 17 for <20 years, 20–30 years and >30 years of kneeling work, respectively. MRI-verified medial meniscal tears was increased among subjects with kneeling work with OR 1.96, 95% CI 0.79 to 4.88 to OR 4.73, 95% CI 1.16 to 19.4 but was not associated with duration of employment. Periarticular bursitis was increased in subjects with <20 years of kneeling working activity. Lateral meniscal tears and PF knee OA were not associated with duration of kneeling working activity or with kneeling work in general. Conclusions The findings suggest a dose–response relationship for radiographic TF knee OA in floor layers with a significant amount of kneeling work and an

  16. Performance of PROMIS for Healthy Patients Undergoing Meniscal Surgery.

    PubMed

    Hancock, Kyle J; Glass, Natalie; Anthony, Chris A; Hettrich, Carolyn M; Albright, John; Amendola, Annunziato; Wolf, Brian R; Bollier, Matthew

    2017-06-07

    The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed as an extensive question bank with multiple health domains that could be utilized for computerized adaptive testing (CAT). In the present study, we investigated the use of the PROMIS Physical Function CAT (PROMIS PF CAT) in an otherwise healthy population scheduled to undergo surgery for meniscal injury with the hypotheses that (1) the PROMIS PF CAT would correlate strongly with patient-reported outcome instruments that measure physical function and would not correlate strongly with those that measure other health domains, (2) there would be no ceiling effects, and (3) the test burden would be significantly less than that of the traditional measures. Patients scheduled to undergo meniscal surgery completed the PROMIS PF CAT, Knee injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale, Short Form-36 (SF-36), and EuroQol-5 Dimension (EQ-5D) questionnaires. Correlations were defined as high (≥0.7), high-moderate (0.61 to 0.69), moderate (0.4 to 0.6), moderate-weak (0.31 to 0.39), or weak (≤0.3). If ≥15% respondents to a patient-reported outcome measure obtained the highest or lowest possible score, the instrument was determined to have a significant ceiling or floor effect. A total of 107 participants were analyzed. The PROMIS PF CAT had a high correlation with the SF-36 Physical Functioning (PF) (r = 0.82, p < 0.01) and KOOS Sport (r = 0.76, p < 0.01) scores; a high-moderate correlation with the KOOS Quality-of-Life (QOL) (r = 0.63, p < 0.01) and EQ-5D (r = 0.62, p < 0.01) instruments; and a moderate correlation with the SF-36 Pain (r = 0.60, p < 0.01), KOOS Symptoms (r = 0.57, p < 0.01), KOOS Activities of Daily Living (ADL) (r = 0.60, p < 0.01), and KOOS Pain (r = 0.60, p < 0.01) scores. The majority (89%) of the patients completed the PROMIS PF CAT after answering only 4 items. The PROMIS PF CAT had no floor or ceiling effects, with 0% of the

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

    PubMed

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

    2017-07-01

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

  18. 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

  19. 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)

  20. [Meniscal injuries of the knee: arthrographic and echographic study].

    PubMed

    Corbetti, F; Tomasella, G

    1989-03-01

    In order to evaluate the diagnostic capabilities of sonography (US) in meniscal lesions of the knee, 65 unquestionable cases of meniscopathy at arthrography were studied with high-resolution US. In 92% of the cases, inhomogeneous echo structure was demonstrated in correspondence with pathological meniscus, with irregular hyperechoic areas and, in some cases, with hyperechoic lines corresponding to the tear. 40% of patients presented with tumefaction and external bulging of the parameniscal region, while in 87% of the cases the articular capsule was thickened. These results confirm that, as reported by some authors, US is a promising method for the study of meniscopathies. We therefore believe that US could nowadays be at least employed as a complement to clinical examination, while its diagnostic capabilities are further assessed through other studies.

  1. Comparable Outcomes After Bucket-Handle Meniscal Repair and Vertical Meniscal Repair Can Be Achieved at a Minimum 2 Years' Follow-up.

    PubMed

    Moatshe, Gilbert; Cinque, Mark E; Godin, Jonathan A; Vap, Alexander R; Chahla, Jorge; LaPrade, Robert F

    2017-08-01

    Meniscal tears can lead to significant pain and disability, necessitating surgical treatment. Nondisplaced vertical tears are usually smaller in size and can be repaired in most cases; however, bucket-handle tears are usually larger and displaced, and the repair of these tears can be challenging. Purpose/Hypothesis: The purpose was to report the outcomes after inside-out vertical mattress suture meniscal repair of bucket-handle tears and to compare these outcomes with those of patients who underwent repair of nondisplaced vertical meniscal tears with a minimum of 2 years' follow-up. The hypothesis was that the outcomes of bucket-handle tear repair would be comparable with those of nondisplaced vertical meniscal tear repair. Cohort study; Level of evidence, 3. Patients who underwent inside-out repair of a bucket-handle meniscal tear or a nondisplaced vertical meniscal tear with a minimum 2 years' follow-up were included in this study. Patients were excluded if they had a diagnosis of a meniscal root tear, underwent a concomitant procedure for a chondral injury, or underwent previous surgical treatment of the same meniscus. Subjective questionnaires were administered preoperatively and postoperatively, including the Lysholm score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Short Form-12 (SF-12) physical component summary (PCS) and mental component summary (MCS), the Tegner activity scale, and patient satisfaction. Thirty-two patients underwent repair for vertical meniscal tears (mean, 7 sutures), while 38 patients underwent repair for bucket-handle meniscal tears (mean, 11 sutures), with a mean follow-up of 3.1 years (range, 2-6 years). There were no significant differences in the preoperative outcome scores between the 2 groups. Significant improvements in patient-reported outcome scores from preoperatively to postoperatively were found in both groups. A direct comparison of the bucket-handle tear group to the vertical tear group

  2. Surgery versus physical therapy for a meniscal tear and osteoarthritis.

    PubMed

    Katz, Jeffrey N; Brophy, Robert H; Chaisson, Christine E; de Chaves, Leigh; Cole, Brian J; Dahm, Diane L; Donnell-Fink, Laurel A; Guermazi, Ali; Haas, Amanda K; Jones, Morgan H; Levy, Bruce A; Mandl, Lisa A; Martin, Scott D; Marx, Robert G; Miniaci, Anthony; Matava, Matthew J; Palmisano, Joseph; Reinke, Emily K; Richardson, Brian E; Rome, Benjamin N; Safran-Norton, Clare E; Skoniecki, Debra J; Solomon, Daniel H; Smith, Matthew V; Spindler, Kurt P; Stuart, Michael J; Wright, John; Wright, Rick W; Losina, Elena

    2013-05-02

    Whether arthroscopic partial meniscectomy for symptomatic patients with a meniscal tear and knee osteoarthritis results in better functional outcomes than nonoperative therapy is uncertain. We conducted a multicenter, randomized, controlled trial involving symptomatic patients 45 years of age or older with a meniscal tear and evidence of mild-to-moderate osteoarthritis on imaging. We randomly assigned 351 patients to surgery and postoperative physical therapy or to a standardized physical-therapy regimen (with the option to cross over to surgery at the discretion of the patient and surgeon). The patients were evaluated at 6 and 12 months. The primary outcome was the difference between the groups with respect to the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical-function score (ranging from 0 to 100, with higher scores indicating more severe symptoms) 6 months after randomization. In the intention-to-treat analysis, the mean improvement in the WOMAC score after 6 months was 20.9 points (95% confidence interval [CI], 17.9 to 23.9) in the surgical group and 18.5 (95% CI, 15.6 to 21.5) in the physical-therapy group (mean difference, 2.4 points; 95% CI, -1.8 to 6.5). At 6 months, 51 active participants in the study who were assigned to physical therapy alone (30%) had undergone surgery, and 9 patients assigned to surgery (6%) had not undergone surgery. The results at 12 months were similar to those at 6 months. The frequency of adverse events did not differ significantly between the groups. In the intention-to-treat analysis, we did not find significant differences between the study groups in functional improvement 6 months after randomization; however, 30% of the patients who were assigned to physical therapy alone underwent surgery within 6 months. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; METEOR ClinicalTrials.gov number, NCT00597012.).

  3. Cartilage Degeneration, Subchondral Mineral and Meniscal Mineral Densities in Hartley and Strain 13 Guinea Pigs.

    PubMed

    Sun, Yubo; Scannell, Brian P; Honeycutt, Patrick R; Mauerhan, David R; H, James Norton; Hanley, Edward N

    2015-01-01

    Osteoarthritis is a joint disease involved in articular cartilage, subchondral bone, meniscus and synovial membrane. This study sought to examine cartilage degeneration, subchondral bone mineral density (BMD) and meniscal mineral density (MD) in male Hartley, female Hartley and female strain 13 guinea pigs to determine the association of cartilage degeneration with subchondral BMD and meniscal MD. Cartilage degeneration, subchondral BMD and meniscal MD in 12 months old guinea pigs were examined with histochemistry, X-ray densitometry and calcium analysis. We found that male Hartley guinea pigs had more severe cartilage degeneration, subchondral BMD and meniscal MD than female Hartley guinea pigs, but not female strain 13 guinea pigs. Female strain 13 guinea pigs had more severe cartilage degeneration and higher subchondral BMD, but not meniscal MD, than female Hartley guinea pigs. These findings indicate that higher subchondral BMD, not meniscal MD, is associated with more severe cartilage degeneration in the guinea pigs and suggest that abnormal subchondral BMD may be a therapeutic target for OA treatment. These findings also indicate that the pathogenesis of OA in the male guinea pigs and female guinea pigs are different. Female strain 13 guinea pig may be used to study female gender-specific pathogenesis of OA.

  4. Signs of knee osteoarthritis common in 620 patients undergoing arthroscopic surgery for meniscal tear.

    PubMed

    Pihl, Kenneth; Englund, Martin; Lohmander, L Stefan; Jørgensen, Uffe; Nissen, Nis; Schjerning, Jeppe; Thorlund, Jonas B

    2017-02-01

    Background and purpose - Recent evidence has questioned the effect of arthroscopic knee surgery for middle-aged and older patients with degenerative meniscal tears with or without concomitant radiographic knee osteoarthritis (OA). We investigated the prevalence of early or more established knee OA and patients' characteristics in a cohort of patients undergoing arthroscopic surgery for a meniscal tear. Patients and methods - 641 patients assigned for arthroscopy on suspicion of meniscus tear were consecutively recruited from February 2013 through January 2015. Of these, 620 patients (mean age 49 (18-77) years, 57% men) with full datasets available were included in the present study. Prior to surgery, patients completed questionnaires regarding onset of symptoms, duration of symptoms, and mechanical symptoms along with the knee injury and osteoarthritis outcome score (KOOS). At arthroscopy, the operating surgeon recorded information about meniscal pathology and cartilage damage. Early or more established knee OA was defined as the combination of self-reported frequent knee pain, cartilage damage, and the presence of degenerative meniscal tissue. Results - 43% of patients (269 of 620) had early or more established knee OA. Of these, a large proportion had severe cartilage lesions with almost half having a severe cartilage lesion in at least 1 knee compartment. Interpretation - Based on a definition including frequent knee pain, cartilage damage, and degenerative meniscal tissue, early or more established knee OA was present in 43% of patients undergoing knee arthroscopy for meniscal tear.

  5. Signs of knee osteoarthritis common in 620 patients undergoing arthroscopic surgery for meniscal tear

    PubMed Central

    Pihl, Kenneth; Englund, Martin; Lohmander, L Stefan; Jørgensen, Uffe; Nissen, Nis; Schjerning, Jeppe; Thorlund, Jonas B

    2017-01-01

    Background and purpose — Recent evidence has questioned the effect of arthroscopic knee surgery for middle-aged and older patients with degenerative meniscal tears with or without concomitant radiographic knee osteoarthritis (OA). We investigated the prevalence of early or more established knee OA and patients’ characteristics in a cohort of patients undergoing arthroscopic surgery for a meniscal tear. Patients and methods — 641 patients assigned for arthroscopy on suspicion of meniscus tear were consecutively recruited from February 2013 through January 2015. Of these, 620 patients (mean age 49 (18–77) years, 57% men) with full datasets available were included in the present study. Prior to surgery, patients completed questionnaires regarding onset of symptoms, duration of symptoms, and mechanical symptoms along with the knee injury and osteoarthritis outcome score (KOOS). At arthroscopy, the operating surgeon recorded information about meniscal pathology and cartilage damage. Early or more established knee OA was defined as the combination of self-reported frequent knee pain, cartilage damage, and the presence of degenerative meniscal tissue. Results — 43% of patients (269 of 620) had early or more established knee OA. Of these, a large proportion had severe cartilage lesions with almost half having a severe cartilage lesion in at least 1 knee compartment. Interpretation — Based on a definition including frequent knee pain, cartilage damage, and degenerative meniscal tissue, early or more established knee OA was present in 43% of patients undergoing knee arthroscopy for meniscal tear. PMID:27798972

  6. Cartilage Degeneration, Subchondral Mineral and Meniscal Mineral Densities in Hartley and Strain 13 Guinea Pigs

    PubMed Central

    Sun, Yubo; Scannell, Brian P; Honeycutt, Patrick R; Mauerhan, David R; H, James Norton; Hanley Jr, Edward N

    2015-01-01

    Osteoarthritis is a joint disease involved in articular cartilage, subchondral bone, meniscus and synovial membrane. This study sought to examine cartilage degeneration, subchondral bone mineral density (BMD) and meniscal mineral density (MD) in male Hartley, female Hartley and female strain 13 guinea pigs to determine the association of cartilage degeneration with subchondral BMD and meniscal MD. Cartilage degeneration, subchondral BMD and meniscal MD in 12 months old guinea pigs were examined with histochemistry, X-ray densitometry and calcium analysis. We found that male Hartley guinea pigs had more severe cartilage degeneration, subchondral BMD and meniscal MD than female Hartley guinea pigs, but not female strain 13 guinea pigs. Female strain 13 guinea pigs had more severe cartilage degeneration and higher subchondral BMD, but not meniscal MD, than female Hartley guinea pigs. These findings indicate that higher subchondral BMD, not meniscal MD, is associated with more severe cartilage degeneration in the guinea pigs and suggest that abnormal subchondral BMD may be a therapeutic target for OA treatment. These findings also indicate that the pathogenesis of OA in the male guinea pigs and female guinea pigs are different. Female strain 13 guinea pig may be used to study female gender-specific pathogenesis of OA. PMID:26401159

  7. Serotonin 1A, 1B, and 7 receptors of the rat medial nucleus accumbens differentially regulate feeding, water intake, and locomotor activity.

    PubMed

    Clissold, Kara A; Choi, Eugene; Pratt, Wayne E

    2013-11-01

    Serotonin (5-HT) signaling has been widely implicated in the regulation of feeding behaviors in both humans and animal models. Recently, we reported that co-stimulation of 5-HT1&7 receptors of the anterior medial nucleus accumbens with the drug 5-CT caused a dose-dependent decrease in food intake, water intake, and locomotion in rats (Pratt et al., 2009). The current experiments sought to determine which of three serotonin receptor subtypes (5-HT1A, 5-HT1B, or 5-HT7) might be responsible for these consummatory and locomotor effects. Food-deprived rats were given 2-h access to rat chow after stimulation of nucleus accumbens 5-HT1A, 5-HT1B, or 5-HT7 receptors, or blockade of the 5-HT1A or 5-HT1B receptors. Stimulation of 5-HT1A receptors with 8-OH-DPAT (at 0.0, 2.0, 4.0, and 8.0 μg/0.5 μl/side) caused a dose-dependent decrease in food and water intake, and reduced rearing behavior but not ambulation. In contrast, rats that received the 5-HT1B agonist CP 93129 (at 0.0, 1.0, 2.0 and 4.0 μg/0.5 μl/side) showed a significant dose-dependent decrease in water intake only; stimulation of 5-HT7 receptors (AS 19; at 0.0, 1.0, and 5.0 μg/0.5 μl/side) decreased ambulatory activity but did not affect food or water consumption. Blockade of 5-HT1A or 5-HT1B receptors had no lasting effects on measures of food consumption. These data suggest that the food intake, water intake, and locomotor effects seen after medial nucleus accumbens injections of 5-CT are due to actions on separate serotonin receptor subtypes, and contribute to growing evidence for selective roles of individual serotonin receptors within the nucleus accumbens on motivated behavior.

  8. Maternal high-fat diet and early life stress differentially modulate spine density and dendritic morphology in the medial prefrontal cortex of juvenile and adult rats.

    PubMed

    Rincel, Marion; Lépinay, Amandine L; Janthakhin, Yoottana; Soudain, Gwenaëlle; Yvon, Sophie; Da Silva, Stéphanie; Joffre, Corinne; Aubert, Agnès; Séré, Alexandra; Layé, Sophie; Theodorou, Vassilia; Ferreira, Guillaume; Darnaudéry, Muriel

    2017-10-11

    The medial prefrontal cortex (mPFC) is a key area for the regulation of numerous brain functions including stress response and cognitive processes. This brain area is also particularly affected by adversity during early life. Using an animal model in rats, we recently demonstrated that maternal exposure to a high-fat diet (HFD) prevents maternal separation (MS)-induced gene expression alterations in the developing PFC and attenuates several long-term deleterious behavioral effects of MS. In the present study, we ask whether maternal HFD could protect mPFC neurons of pups exposed to early life stress by examining dendritic morphology and spine density in juvenile [postnatal day (PND) 21] and adult rats submitted to MS. Dams were fed either a control or an HFD throughout gestation and lactation, and pups were submitted to MS from PND2 to PND14. We report that maternal HFD prevents MS-induced spine loss at PND21 and dendritic atrophy at adulthood. Furthermore, we show in adult MS rats that PFC-dependent memory extinction deficits are prevented by maternal HFD. Finally, perinatal HFD exposure reverses gut leakiness following stress in pups and seems to exert an anti-stress effect in dams. Overall, our work demonstrates that maternal HFD affects the developing brain and suggests that nutrition, possibly through gut-brain interactions, could modulate mPFC sensitivity to early stress.

  9. 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 Central

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

    2015-01-01

    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

  10. 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. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. Differential Activation of Fast-Spiking and Regular-Firing Neuron Populations During Movement and Reward in the Dorsal Medial Frontal Cortex

    PubMed Central

    Insel, Nathan; Barnes, Carol A.

    2015-01-01

    The medial prefrontal cortex is thought to be important for guiding behavior according to an animal's expectations. Efforts to decode the region have focused not only on the question of what information it computes, but also how distinct circuit components become engaged during behavior. We find that the activity of regular-firing, putative projection neurons contains rich information about behavioral context and firing fields cluster around reward sites, while activity among putative inhibitory and fast-spiking neurons is most associated with movement and accompanying sensory stimulation. These dissociations were observed even between adjacent neurons with apparently reciprocal, inhibitory–excitatory connections. A smaller population of projection neurons with burst-firing patterns did not show clustered firing fields around rewards; these neurons, although heterogeneous, were generally less selective for behavioral context than regular-firing cells. The data suggest a network that tracks an animal's behavioral situation while, at the same time, regulating excitation levels to emphasize high valued positions. In this scenario, the function of fast-spiking inhibitory neurons is to constrain network output relative to incoming sensory flow. This scheme could serve as a bridge between abstract sensorimotor information and single-dimensional codes for value, providing a neural framework to generate expectations from behavioral state. PMID:24700585

  12. Organization of food protection behavior is differentially influenced by 192 IgG-saporin lesions of either the medial septum or the nucleus basalis magnocellularis.

    PubMed

    Martin, Megan M; Winter, Shawn S; Cheatwood, Joseph L; Carter, Lynniece A; Jones, Jeana L; Weathered, Scott L; Wagner, Steven J; Wallace, Douglas G

    2008-11-19

    Converging lines of evidence have supported a role for the nucleus basalis magnocellularis (NB) in attentional mechanisms; however, debate continues regarding the role of the medial septum in behavior (MS). Recent studies have supported a role for the septohippocampal system in the online processing of internally generated cues. The current study was designed to investigate a possible double dissociation in rat food protection behavior, a natural behavior that has been shown to depend on external and internal sources of information. The study examined the effects of intraparenchymal injections of 192 IgG-saporin into either the MS or NB on the organization of food protection behavior. NB cholinergic lesions reduced the number of successful food protection behaviors while sparing the temporal organization of food protection behavior. In contrast, MS cholinergic lesions disrupted the temporal organization of food protection behavior while sparing the ability to successfully protect food items. These observations are consistent with a double dissociation of NB and MS cholinergic systems' contributions to processing external and internal sources of information and provide further evidence for the septohippocampal system's involvement in processing internally generated cues.

  13. Neuroeconomics of attention-deficit/hyperactivity disorder: differential influences of medial, dorsal, and ventral prefrontal brain networks on suboptimal decision making?

    PubMed

    Sonuga-Barke, Edmund J S; Fairchild, Graeme

    2012-07-15

    Psychiatric neuroeconomics offers an alternative approach to understanding mental disorders by studying the way disorder-related neurobiological alterations constrain economic agency, as revealed through decisions about choices between future goods. In this article, we apply this perspective to understand suboptimal decision making in attention-deficit/hyperactivity disorder (ADHD) by integrating recent advances in the neuroscience of decision making and studies of the pathophysiology of ADHD. We identify three brain networks as candidates for further study and develop specific hypotheses about how these could be implicated in ADHD. First, we postulate that altered patterns of connectivity within a network linking medial prefrontal cortex and posterior cingulate cortex (i.e., the default mode network) disrupts ordering of utilities, prospection about desired future states, setting of future goals, and implementation of aims. Second, we hypothesize that deficits in dorsal frontostriatal networks, including the dorsolateral prefrontal cortex and dorsal striatum, produce executive dysfunction-mediated impairments in the ability to compare outcome options and make choices. Third, we propose that dopaminergic dysregulation in a ventral frontostriatal network encompassing the orbitofrontal cortex, ventral striatum, and amygdala disrupts processing of cues of future utility, evaluation of experienced outcomes (feedback), and learning of associations between cues and outcomes. Finally, we extend this perspective to consider three contemporary themes in ADHD research.

  14. 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

  15. Medial subluxation of the patella without previous lateral retinacular release.

    PubMed

    Richman, N M; Scheller, A D

    1998-07-01

    This case presented a 17-year-old patient with persistent complaints localized to the right patellofemoral joint. Clinical examination demonstrated increased medial translation of the patella on manual stress. In contrast to previous published reports on medial patellar subluxation, this patient had not undergone prior lateral retinacular release. Arthroscopic examination documented medial tracking of the patella as well as excess medial translation. Imbrication of the patient's lateral patellar retinaculum centralized patella tracking and diminished medial translation on stress testing as observed arthroscopically and clinically. This case illustrates that medial patellar subluxation is a subtle problem that may be overlooked in the patient presenting with patellofemoral complaints and should be included in the differential diagnosis.

  16. Differential role of the dorsal hippocampus, ventro-intermediate hippocampus, and medial prefrontal cortex in updating the value of a spatial goal.

    PubMed

    De Saint Blanquat, Paul; Hok, Vincent; Save, Etienne; Poucet, Bruno; Chaillan, Franck A

    2013-05-01

    Encoding of a goal with a specific value while performing a place navigation task involves the medial prefrontal cortex (mPFC) and the dorsal hippocampus (dHPC), and depends on the coordination between mPFC and the ventro-intermediate hippocampus (vHPC).The present work investigates the contribution of mPFC, dHPC, and vHPC when the rat has to update the value of a goal. Rats were trained to navigate to an uncued goal in order to release a food pellet in a continuous place navigation task. When they had reached criterion performance level in the task, they were subjected to a single "flash session" in which they were exposed to an aversive strobe light during goal visits instead of receiving a food reward. Just before the flash session, the GABA(A) agonist muscimol was injected to temporarily inactivate mPFC, dHPC, or vHPC. The ability to recall the changed value of the goal was tested on the next day. We first demonstrate the aversive effect of the strobe light by showing that rats learn to avoid the goal much more rapidly in the flash session than during a simple extinction session in which goal visits are not rewarded. Furthermore, while dHPC inactivation had no effect on learning and recalling the new goal value, vHPC muscimol injections considerably delayed goal value updating during the flash session, which resulted in a slight deficit during recall. In contrast, mPFC muscimol injections induced faster goal value updating but the rats were markedly impaired on recalling the new goal value on the next day. These results suggest that, contrary to mPFC and dHPC, vHPC is required for updating the value of a goal. In contrast, mPFC is necessary for long-term retention of this updating.

  17. Differential dorsal and ventral medial prefrontal representations of the implicit self modulated by individualism and collectivism: An fMRI study.

    PubMed

    Harada, Tokiko; Li, Zhang; Chiao, Joan Y

    2010-01-01

    Individualism and collectivism, or self-construal style, refer to cultural values that influence how people think about themselves and their relation to the social and physical environment. Recent neuroimaging evidence suggests that cultural values of individualism and collectivism dynamically modulate neural response within cortical midline structures, such as the medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC), during explicit self-evaluation. However, it remains unknown whether cultural priming modulates neural response during self-evaluation due to explicit task demands. Here we investigated how cultural priming of self-construal style affects neural activity within cortical midline structures during implicit self-evaluation in bicultural individuals. Results indicate that ventral MPFC showed relatively less deactivation during implicit evaluation of both self- and father-relevant information as compared to control condition (e.g., information of an unfamiliar person), irrespective of cultural priming. By contrast, dorsal MPFC showed relatively less deactivation during implicit evaluation of father-relevant information, but not self-relevant information, as compared to control condition, only when they were primed with individualism. Furthermore, dorsal MPFC showed relatively less deactivation during implicit evaluation of father-relevant information as compared to self-relevant condition only when they were primed with individualism. Hence, our results indicate that cultural priming modulates neural response within dorsal, but not ventral, portions of MPFC in a stimulus-driven rather than task-driven manner. More broadly, these findings suggest that cultural values dynamically shape neural representations during the evaluation, rather than the detection, of self-relevant information.

  18. The Abused Inhalant Toluene Differentially Modulates Excitatory and Inhibitory Synaptic Transmission in Deep-Layer Neurons of the Medial Prefrontal Cortex

    PubMed Central

    Beckley, Jacob T; Woodward, John J

    2011-01-01

    Volatile organic solvents such as toluene are voluntarily inhaled for their intoxicating effects. Solvent use is especially prevalent among adolescents, and is associated with deficits in a wide range of cognitive tasks including attention, behavioral control, and risk assessment. Despite these findings, little is known about the effects of toluene on brain areas mediating these behaviors. In this study, whole-cell patch-clamp recordings were used to determine the effect toluene on neurons within the medial PFC, a region critically involved in cognitive function. Toluene had no effect on measures of intrinsic excitability, but enhanced stimulus-evoked γ-amino butyric acid A-mediated inhibitory postsynaptic currents (IPSCs). In the presence of tetrodotoxin (TTX) to block action potentials, toluene increased the frequency and amplitude of miniature IPSCs. In contrast, toluene induced a delayed but persistent decrease in evoked or spontaneous AMPA-mediated excitatory postsynaptic currents (EPSCs). This effect was prevented by an intracellular calcium chelator or by the ryanodine receptor and SERCA inhibitors, dantrolene or thapsigargin, respectively, suggesting that toluene may mobilize intracellular calcium pools. The toluene-induced reduction in AMPA EPSCs was also prevented by a cannabinoid receptor (CB1R) antagonist, and was occluded by the CB1 agonist WIN 55,212-2 that itself induced a profound decrease in AMPA-mediated EPSCs. Toluene had no effect on the frequency or amplitude of miniature EPSCs recorded in the presence of TTX. Finally, toluene dose-dependently inhibited N-methyl--aspartate (NMDA)-mediated EPSCs and the magnitude and reversibility of this effect was CB1R sensitive indicating both direct and indirect actions of toluene on NMDA-mediated responses. Together, these results suggest that the effect of toluene on cognitive behaviors may result from its action on inhibitory and excitatory synaptic transmission of PFC neurons. PMID:21430649

  19. 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.

  20. Autophagy protects meniscal cells from glucocorticoids-induced apoptosis via inositol trisphosphate receptor signaling.

    PubMed

    Shen, Chao; Gu, Wen; Cai, Gui-Quan; Peng, Jian-Ping; Chen, Xiao-Dong

    2015-09-01

    Intra-articular injection of glucocorticoids (GCs) has been widely used in the management of osteoarthritis and rheumatoid arthritis. Nevertheless, several studies showed that GCs had toxic effects on chondrocytes as well as synovial cells. Previously we reported the protective role of autophagy in the degeneration of meniscal tissues. However, the effects of GCs on autophagy in the meniscal cells have not been fully elucidated. To investigate whether GCs can regulate autophagy in human meniscal cells, the meniscal cells were cultured in vitro and exposed in the presence of dexamethasone. The levels of apoptosis and autophagy were investigated via flow cytometry as well as western blotting analysis. The changes of the aggrecanases were measured using real-time PCR. The role of autophagy in dexamethasone-induced apoptosis was investigated using pharmacological agents and RNA interference technique. An agonist of inositol 1,4,5-trisphosphate receptor (IP3R) was used to investigate the mechanism of dexamethasone-induced autophagy. The results showed that dexamethasone induced autophagy as well as apoptosis in normal human meniscal cells. Using RNA interference technique and pharmacological agents, our results showed that autophagy protected the meniscal cells from dexamethasone-induced apoptosis. Our results also indicated that dexamethasone increased the mRNA levels of aggrecanases. This catabolic effect of dexamethasone was enhanced by 3-MA, the autophagy inhibitor. Furthermore, our results showed that dexamethasone induced autophagy via suppressing the phosphorylation of IP3R. In summary, our results indicated that autophagy protected meniscal cells from GCs-induced apoptosis via inositol trisphosphate receptor signaling.

  1. 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

  2. Function of the medial meniscus in force transmission and stability.

    PubMed

    Walker, Peter S; Arno, Sally; Bell, Christopher; Salvadore, Gaia; Borukhov, Ilya; Oh, Cheongeun

    2015-06-01

    We studied the combined role of the medial meniscus in distributing load and providing stability. Ten normal knees were loaded in combinations of compressive and shear loading as the knee was flexed over a full range. A digital camera tracked the motion, from which femoral-tibial contacts were determined by computer modelling. Load transmission was determined from the Tekscan for the anterior horn, central body, posterior horn, and the uncovered cartilage in the centre of the meniscus. For the three types of loading; compression only, compression and anterior shear, compression and posterior shear; between 40% and 80% of the total load was transmitted through the meniscus. The overall average was 58%, the remaining 42% being transmitted through the uncovered cartilage. The anterior horn was loaded only up to 30 degrees flexion, but played a role in controlling anterior femoral displacement. The central body was loaded 10-20% which would provide some restraint to medial femoral subluxation. Overall the posterior horn carried the highest percentage of the shear load, especially after 30 degrees flexion when a posterior shear force was applied, where the meniscus was estimated to carry 50% of the shear force. This study added new insights into meniscal function during weight bearing conditions, particularly its role in early flexion, and in transmitting shear forces.

  3. 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

  4. Surgery versus Physical Therapy for a Meniscal Tear and Osteoarthritis

    PubMed Central

    Katz, Jeffrey N.; Brophy, Robert H.; Chaisson, Christine E.; de Chaves, Leigh; Cole, Brian J.; Dahm, Diane L.; Donnell-Fink, Laurel A.; Guermazi, Ali; Haas, Amanda K.; Jones, Morgan H.; Levy, Bruce A.; Mandl, Lisa A.; Martin, Scott D.; Marx, Robert G.; Miniaci, Anthony; Matava, Matthew J.; Palmisano, Joseph; Reinke, Emily K.; Richardson, Brian E.; Rome, Benjamin N.; Safran-Norton, Clare E.; Skoniecki, Debra J.; Solomon, Daniel H.; Smith, Matthew V.; Spindler, Kurt P.; Stuart, Michael J.; Wright, John; Wright, Rick W.; Losina, Elena

    2013-01-01

    BACKGROUND Whether arthroscopic partial meniscectomy for symptomatic patients with a meniscal tear and knee osteoarthritis results in better functional outcomes than nonoperative therapy is uncertain. METHODS We conducted a multicenter, randomized, controlled trial involving symptomatic patients 45 years of age or older with a meniscal tear and evidence of mild-to-moderate osteoarthritis on imaging. We randomly assigned 351 patients to surgery and postoperative physical therapy or to a standardized physical-therapy regimen (with the option to cross over to surgery at the discretion of the patient and surgeon). The patients were evaluated at 6 and 12 months. The primary outcome was the difference between the groups with respect to the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical-function score (ranging from 0 to 100, with higher scores indicating more severe symptoms) 6 months after randomization. RESULTS In the intention-to-treat analysis, the mean improvement in the WOMAC score after 6 months was 20.9 points (95% confidence interval [CI], 17.9 to 23.9) in the surgical group and 18.5 (95% CI, 15.6 to 21.5) in the physical-therapy group (mean difference, 2.4 points; 95% CI, −1.8 to 6.5). At 6 months, 51 active participants in the study who were assigned to physical therapy alone (30%) had undergone surgery, and 9 patients assigned to surgery (6%) had not undergone surgery. The results at 12 months were similar to those at 6 months. The frequency of adverse events did not differ significantly between the groups. CONCLUSIONS In the intention-to-treat analysis, we did not find significant differences between the study groups in functional improvement 6 months after randomization; however, 30% of the patients who were assigned to physical therapy alone underwent surgery within 6 months. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; METEOR ClinicalTrials.gov number, NCT00597012

  5. Study protocol for a randomised controlled trial of meniscal surgery compared with exercise and patient education for treatment of meniscal tears in young adults.

    PubMed

    Skou, Søren Thorgaard; Lind, Martin; Hölmich, Per; Jensen, Hans Peter; Jensen, Carsten; Afzal, Muhammad; Jørgensen, Uffe; Thorlund, Jonas Bloch

    2017-08-21

    Arthroscopic surgery is a very common orthopaedic procedure. While several trials have investigated the effect of knee arthroscopy for middle-aged and older patients with meniscal tears, there is a paucity of trials comparing meniscal surgery with non-surgical treatment for younger adults. The aim of this randomised controlled trial (RCT) is to investigate if early arthroscopic surgery is superior to exercise therapy and education, with the option of later surgery if needed, in improving pain, function and quality of life in younger adults with meniscal tears. This is a protocol for a multicentre, parallel-group RCT conducted at six hospitals across all five healthcare regions in Denmark. 140 patients aged 18-40 years with a clinical history and symptoms consistent with a meniscal tear, verified on MRI, found eligible for meniscal surgery by an orthopaedic surgeon will be randomly allocated to one of two groups (1:1 ratio). Participants randomised to surgery will undergo either arthroscopic partial meniscectomy or meniscal repair followed by standard postsurgical care, while participants allocated to exercise and education will undergo a 12-week individualised, supervised neuromuscular and strengthening exercise programme and patient education. The primary outcome will be difference in change from baseline to 12 months in the mean score on four Knee Injury and Osteoarthritis Outcome Score subscales, covering pain, symptoms, function in sports and recreation and quality of life (Knee Injury and Osteoarthritis Outcome Score (KOOS4)) supported by the individual subscale scores allowing clinical interpretation. Alongside, the RCT an observational cohort will follow patients aged 18-40 years with clinical suspicion of a meniscal tear, but not fully eligible or declining to participate in the trial. Results will be presented in peer-reviewed journals and at international conferences. This study is approved by the Regional Committees on Health Research Ethics for Southern

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

    PubMed

    Song, Chenghui; Ehlers, Vanessa L; Moyer, James R

    2015-09-30

    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

  7. 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

  8. 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

  9. Differential effects of lesions in the subareas of medial prefrontal cortex on the development of behavioral sensitization to amphetamine: the role of environmental context.

    PubMed

    Liao, Ruey-Ming; Lin, Huai-Liu

    2008-12-31

    Based on the notion of the heterogeneity of the medial prefrontal cortex (mPFC), the effects of lesions of the dorsal and ventral subareas of mPFC were examined on the development of behavioral sensitization induced by d-amphetamine (AMP). The first part of this study determined behavioral sensitization to AMP by the use of the rat with intermittent repeated AMP administrations in three types of environmental context including an infrared locomotor activity test-box, the home cage, and a novel third place. In experimental groups, each subject was initially injected with AMP of 0.5 mg/kg as the pretest treatment and then received seven injections of AMP (1 mg/kg) every other day in the context where it was assigned. Following two days of withdrawal, the subject was challenged by AMP of 0.5 mg/kg as the post-test treatment. Behavioral sensitization to AMP on the locomotor activity was determined by the difference between pre- and post-test. The results showed that the most profound locomotor sensitization to AMP appeared in the test box group. A less but significant degree of locomotor sensitization to AMP was observed for the home cage group. A trend of locomotor sensitization to AMP observed in the novel third place group was not statistically confirmed. In the second part of experiment, we then investigated the effects of lesions in the dorsal and ventral mPFC subareas on the development of locomotor sensitization to AMP in the test box and home cage. Results showed that locomotor sensitization was significantly appeared in every sham-operated control group tested in either test box or home cage. Lesions of ventral mPFC significantly inhibited the development of locomotor sensitization to AMP in test box, but not in home cage. Lesions of dorsal mPFC failed to affect AMP locomotor sensitization developed in either test box or home cage. These data indicate that the heterogeneous functions of mPFC subareas involved in the development of behavioral sensitization to

  10. Meniscal Measurements of T1ρ and T2 at MR Imaging in Healthy Subjects and Patients with Osteoarthritis

    PubMed Central

    Rauscher, Isabel; Stahl, Robert; Cheng, Jonathan; Li, Xiaojuan; Huber, Markus B.; Luke, Anthony; Majumdar, Sharmila; Link, Thomas M.

    2008-01-01

    Purpose: To prospectively evaluate differences in T1ρ (T1 relaxation time in the rotating frame) and T2 values in the meniscus at magnetic resonance (MR) imaging in both patients with varying degrees of osteoarthritis (OA) and healthy control subjects. Materials and Methods: The study was institutional review board approved and HIPAA compliant. Written informed consent was obtained from all subjects. T1ρ and T2 measurements were performed at 3.0-T MR imaging in 60 subjects deemed to be healthy (n = 23; mean age, 34.1 years ± 10.0 [standard deviation]; age range, 23–59 years), having mild OA (n = 27; mean age, 52.5 years ± 10.9; age range, 32–69 years), or having severe OA (n = 10; mean age, 61.6 years ± 11.6; age range, 50–86 years). Semiautomatic segmentation was performed to generate T1ρ and T2 maps of the menisci. Clinical findings were assessed by using Western Ontario and McMaster Osteoarthritis (WOMAC) questionnaires. Differences in T1ρ and T2 values between the three subject groups were calculated by using two-tailed t tests (with P < .05 indicating significance), and receiver operating characteristic analyses were performed. Correlations of meniscal T1ρ and T2 values with age, cartilage-derived T1ρ and T2 parameters, and WOMAC scores were calculated. Results: Significant differences between the three subject groups were found: Mean T1ρ values were 14.7 msec ± 5.5, 16.1 msec ± 6.6, and 19.3 msec ± 7.6 for the healthy, mild OA, and severe OA groups, respectively. Mean T2 values were 11.4 msec ± 3.9, 13.5 msec ± 4.7, and 16.6 msec ± 8.2 for the healthy, mild OA, and severe OA groups, respectively. Correlations of meniscal T1ρ and T2 values with subject age (R2 = 0.18, for correlation with T2 only), cartilage-derived parameters (R2 = 0.14–0.29), and WOMAC scores (R2 = 0.11–0.45) were significant. Conclusion: Meniscal T1ρ and T2 values correlate with clinical findings of OA and can be used to differentiate healthy subjects from

  11. Lateral lid lysis for medial lid and medial canthus lacerations.

    PubMed

    Hecht, S D; Dijkstal, D

    1985-02-01

    Techniques are now being used to provide adequate healing time for medial lid and medial canthal full-thickness lacerations. Lateral upper and lower lid lysis allows the needed extended period of healing.

  12. Three-dimensional reconstructed magnetic resonance scans: Accuracy in identifying and defining knee meniscal tears

    PubMed Central

    Kruger, Neil; McNally, Eugene; Al-Ali, Sami; Rout, Raj; Rees, Jonathan L; Price, Andrew J

    2016-01-01

    AIM To determine whether three-dimensional (3D) reconstruction from conventional magnetic resonance imaging (MRI) is able to accurately detect a meniscal tear, and define the configuration. METHODS Thirty-three patients’ 3T MRI scan data were collected and sagittal uni-planar 3D reconstructions performed from the preoperative MRI. There were 24 meniscal tears in 24 patients, and nine controls. All patients had arthroscopic corroboration of MRI findings. Two independent observers prospectively reported on all 33 reconstructions. Meniscal tear presence or absence was noted, and tear configuration subsequently categorised as either radial, bucket-handle, parrot beak, horizontal or complex. RESULTS Identification of control menisci or meniscal tear presence was excellent (Accuracy: observer 1 = 90.9%; observer 2 = 81.8%). Of the tear configurations, bucket handle tears were accurately identified (Accuracy observer 1 and 2 = 80%). The remaining tear configurations were not accurately discernable. CONCLUSION Uni-planar 3D reconstruction from 3T MRI knee scan sequences are useful in identifying normal menisci and menisci with bucket-handle tears. Advances in MRI sequencing and reconstruction software are awaited for accurate identification of the remaining meniscal tear configurations. PMID:27900270

  13. 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.

  14. Assessment of apoptosis and MMP-1, MMP-3 and TIMP-2 expression in tibial hyaline cartilage after viable medial meniscus transplantation in the rabbit

    PubMed Central

    Stasikowska-Kanicka, Olga; Danilewicz, Marian; Fabiś, Jarosław

    2012-01-01

    Introduction The porpuse of this animal study was to assess chondrocyte apoptosis and MMP-1, MMP-3 and TIMP-2 expression in rabbit tibial cartilage 6 months after viable medial meniscal autografts and allografts. Material and methods Twenty white male New Zealand rabbits were chosen for the study. The medial meniscus was excised from 14 animals and stored under tissue culture conditions for 2 weeks, following which t of them were implantated as autografts and 7 as allografts. The control group consisted of 6 animals which underwent arthtrotomy. When the animals were eutanized, the tibial cartilage was used for immunohisochemical examination. Apoptosis (TUNEL method) and MMP-1, MMP-3 and TIMP-2 expression were estimated semiquantatively. Results An increased level of chodrocyte apoptosis in the tibail cartilage was observed after both kinds of transplants (p < 0.05), allografts (1.43 ±0.98) and autografts (0.86 ±0.69); no statistical diferences existed between them. An increased level of metalloproteinases and TIMP-2 expression was obreved only after allografts with statistical differences among the allograft group, the autograft group nad the control group (p < 0.05). Conclusions Our findings suggest that the meniscal graft does not protect the hyaline cartilage against excessive apoptosis. The results of experimantal studies on humans indicate the need to device a method of apoptosis inhibition in the hyaline cartilage to improve long-term results of meniscal transplantation. PMID:23319989

  15. Assessment of apoptosis and MMP-1, MMP-3 and TIMP-2 expression in tibial hyaline cartilage after viable medial meniscus transplantation in the rabbit.

    PubMed

    Zwierzchowski, Tomasz J; Stasikowska-Kanicka, Olga; Danilewicz, Marian; Fabiś, Jarosław

    2012-12-20

    The porpuse of this animal study was to assess chondrocyte apoptosis and MMP-1, MMP-3 and TIMP-2 expression in rabbit tibial cartilage 6 months after viable medial meniscal autografts and allografts. Twenty white male New Zealand rabbits were chosen for the study. The medial meniscus was excised from 14 animals and stored under tissue culture conditions for 2 weeks, following which t of them were implantated as autografts and 7 as allografts. The control group consisted of 6 animals which underwent arthtrotomy. When the animals were eutanized, the tibial cartilage was used for immunohisochemical examination. Apoptosis (TUNEL method) and MMP-1, MMP-3 and TIMP-2 expression were estimated semiquantatively. An increased level of chodrocyte apoptosis in the tibail cartilage was observed after both kinds of transplants (p < 0.05), allografts (1.43 ±0.98) and autografts (0.86 ±0.69); no statistical diferences existed between them. An increased level of metalloproteinases and TIMP-2 expression was obreved only after allografts with statistical differences among the allograft group, the autograft group nad the control group (p < 0.05). Our findings suggest that the meniscal graft does not protect the hyaline cartilage against excessive apoptosis. The results of experimantal studies on humans indicate the need to device a method of apoptosis inhibition in the hyaline cartilage to improve long-term results of meniscal transplantation.

  16. Extra-articular Mimickers of Lateral Meniscal Tears

    PubMed Central

    Barker, Joseph U.; Strauss, Eric J.; Lodha, Sameer; Bach, Bernard R.

    2011-01-01

    Context: Lateral meniscus tears are a common entity seen in sports medicine. Although lateral-side knee pain is often the result of a meniscus injury, several extra-articular pathologies share signs and symptoms with a meniscus tear. It is critical for the clinician to be able to identify and understand extra-articular pathologies that can present similar to a lateral meniscus tear. Evidence Acquisition: Data were collected through a thorough review of the literature conducted through a MEDLINE search for all relevant articles between 1980 and February 2010. Study Type: Clinical review. Results: Common extra-articular pathologies that can mimic lateral meniscal tears include iliotibial band syndrome, proximal tibiofibular joint instability, snapping biceps femoris or popliteus tendons, and peroneal nerve compression syndrome or neuritis. The patient history, physical examination features, and radiographic findings can be used to separate these entities from the more common intra-articular knee pathologies. Conclusions: In treating patients who present with lateral-sided knee pain, clinicians should be able to recognize and treat extra-articular pathologies that can present in a similar fashion as lateral meniscus tears. PMID:23015995

  17. Overlap Between Anterior Cruciate Ligament and Anterolateral Meniscal Root Insertions: A Scanning Electron Microscopy Study.

    PubMed

    Steineman, Brett D; Moulton, Samuel G; Haut Donahue, Tammy L; Fontboté, Cristián A; LaPrade, Christopher M; Cram, Tyler R; Dean, Chase S; LaPrade, Robert F

    2017-02-01

    The anterolateral meniscal root (ALMR) has been reported to intricately insert underneath the tibial insertion of the anterior cruciate ligament (ACL). Previous studies have begun to evaluate the relationship between the insertion areas and the risk of iatrogenic injuries; however, the overlap of the insertions has yet to be quantified in the sagittal and coronal planes. To investigate the insertions of the human tibial ACL and ALMR using scanning electron microscopy (SEM) and to quantify the overlap of the ALMR insertion in the coronal and sagittal planes. Descriptive laboratory study. Ten cadaveric knees were dissected to isolate the tibial ACL and ALMR insertions. Specimens were prepared and imaged in the coronal and sagittal planes. After imaging, fiber directions were examined to identify the insertions and used to calculate the percentage of the ACL that overlaps with the ALMR instead of inserting into bone. Four-phase insertion fibers of the tibial ACL were identified directly medial to the ALMR insertion as they attached onto the tibial plateau. The mean percentage of ACL fibers overlapping the ALMR insertion instead of inserting into subchondral bone in the coronal and sagittal planes was 41.0% ± 8.9% and 53.9% ± 4.3%, respectively. The percentage of insertion overlap in the sagittal plane was significantly higher than in the coronal plane ( P = .02). This study is the first to quantify the ACL insertion overlap of the ALMR insertion in the coronal and sagittal planes, which supplements previous literature on the insertion area overlap and iatrogenic injuries of the ALMR insertion. Future studies should determine how much damage to the ALMR insertion is acceptable to properly restore ACL function without increasing the risk for tears of the ALMR. Overlap of the insertion areas on the tibial plateau has been previously reported; however, the results of this study demonstrate significant overlap of the insertions superior to the insertion sites on the

  18. Meniscal Allograft Transplantation With Soft Tissue in Bone Socket Fixation: Arthroscopic Technique With Technical Pearls.

    PubMed

    Roberson, Troy A; Wyland, Douglas J

    2017-04-01

    Meniscal allograft transplantation may slow the progression of degenerative changes in the meniscus-deficient knee. The current literature suggests patients can experience good early to mid-term satisfaction and patient-reported outcomes with reasonable expectations of return to work. More ambitious applications in athletes have also shown good results although long-term data are lacking. Traditionally, meniscal allograft transplantation has been considered an open procedure with incorporation of bone blocks from the allograft source. However, as arthroscopic techniques have advanced, it has become possible to perform this procedure through a predominantly arthroscopic approach while securing the soft tissue graft in bone tunnels. The current demonstration provides this background and technical pearls for success in arthroscopic meniscal allograft transplantation.

  19. Arthroscopic meniscal transplants in soccer players: outcomes at 2- to 5-year follow-up.

    PubMed

    Alentorn-Geli, Eduard; Vázquez, Roberto Seijas; Díaz, Pedro Alvarez; Cuscó, Xavier; Cugat, Ramón

    2010-09-01

    To assess the midterm effects of meniscal transplants on clinical and functional knee scores and on the return to sports rate in soccer players. Retrospective case series. Department of Orthopaedic Surgery, Clínica del Pilar, Barcelona, Spain. Fifty-nine meniscal transplants in 57 patients between 2001 and 2006 were reviewed. Only soccer players with a history of meniscectomy and no other ipsilateral knee surgeries before or after the meniscal transplant were included in the study. Fifteen patients met inclusion criteria. Main outcomes were obtained from the sample after meniscal transplant and compared with preoperative data, with a mean follow-up of 36 months. A subgroup analysis was performed considering the degree of chondral lesion (no lesions, grade I-II, and grade III-IV). Scores on Lysholm, Subjective International Knee Documentation Committee (IKDC) form, and visual analog scale (VAS) scale for pain and information regarding return to play. One of the 15 patients had a graft failure (6.6%) after a daily life accident. Twelve of the 14 patients included in the analysis (85.7%) returned to play soccer. Patients demonstrated significant improvements for Lysholm (P = 0.006), Subjective IKDC Form (P = 0.001), and VAS for pain (P < 0.0001) scores after the meniscal transplant. Depending on the degree of chondral lesion (subgroup analysis), there were no significant interactions for Lysholm, Subjective IKDC Form, and VAS for pain scores. Arthroscopic meniscal transplants improve knee symptoms and knee function and allow return to play in soccer players, regardless of the degree of chondral lesion.

  20. Arthroscopic Meniscal Transplants in Soccer Players: Outcomes at 2- to 5-Year Follow-up.

    PubMed

    Alentorn-Geli, Eduard; Vázquez, Roberto Seijas; Díaz, Pedro Álvarez; Cuscó, Xavier; Cugat, Ramón

    2010-09-01

    To assess the midterm effects of meniscal transplants on clinical and functional knee scores and on the return to sports rate in soccer players. Retrospective case series. Department of Orthopaedic Surgery, Clínica del Pilar, Barcelona, Spain. Fifty-nine meniscal transplants in 57 patients between 2001 and 2006 were reviewed. Only soccer players with a history of meniscectomy and no other ipsilateral knee surgeries before or after the meniscal transplant were included in the study. Fifteen patients met inclusion criteria. Main outcomes were obtained from the sample after meniscal transplant and compared with preoperative data, with a mean follow-up of 36 months. A subgroup analysis was performed considering the degree of chondral lesion (no lesions, grade I-II, and grade III-IV). Scores on Lysholm, Subjective International Knee Documentation Committee (IKDC) form, and visual analog scale (VAS) scale for pain and information regarding return to play. One of the 15 patients had a graft failure (6.6%) after a daily life accident. Twelve of the 14 patients included in the analysis (85.7%) returned to play soccer. Patients demonstrated significant improvements for Lysholm (P = 0.006), Subjective IKDC Form (P = 0.001), and VAS for pain (P < 0.0001) scores after the meniscal transplant. Depending on the degree of chondral lesion (subgroup analysis), there were no significant interactions for Lysholm, Subjective IKDC Form, and VAS for pain scores. Arthroscopic meniscal transplants improve knee symptoms and knee function and allow return to play in soccer players, regardless of the degree of chondral lesion.

  1. Comparison of knee kinematics between meniscal tear and normal control during a step-down task.

    PubMed

    Nicolas, Roy; Nicolas, Boudreau; François, Vézina; Michel, Tousignant; Nathaly, Gaudreault

    2015-08-01

    Difficulty descending stairs is a common functional complaint reported by patients with meniscal tears. Abnormal knee movement patterns, such as dynamic valgus of the knee or decreased knee flexion during step down, have been reported by clinicians, but 3D knee kinematics descending stairs has never been described in this population. The objective of this study is to compare 3D knee kinematics of individuals with a meniscal tear to that of control individuals during a step-down task. Ten participants (6 men and 4 women) diagnosed with a meniscal tear and eleven healthy participants (3 men and 8 women) were recruited. Three-dimensional knee kinematic data were recorded during five step-down task trials with a VICON™ motion analysis system. The following parameters were extracted from the stance phase period only: maximum angle, minimum knee angle, and range of motion (maximum minus minimum) values for sagittal, frontal, and transverse planes. A group comparison was performed by ANOVA using the velocity of the step-down task as the control variable. Significant reductions in the mean maximum knee flexion angle, knee flexion/extension range of motion, and knee abduction/adduction were observed among the participants with a meniscal tear compared to the control group (mean differences and P values were 4.7°, P=0.02; 5.4°, P=0.02 and 1.6°, P=0.03 respectively). Differences in rotation movement were not significant. This study is the first to describe and compare 3D knee kinematics of persons with a meniscal tear during a step-down task. These findings support that significant kinematic changes occur in the sagittal and frontal plane in individuals with a meniscal tear compared to normal controls. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. [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.

  3. Medial plica syndrome.

    PubMed

    Sznajderman, Tal; Smorgick, Yossi; Lindner, Dror; Beer, Yiftah; Agar, Gabriel

    2009-01-01

    Synovial plicae are membranous inward folds of the synovial lining of the knee joint capsula. Such folds are regularly found in the human knee, but most are asymptomatic and of little clinical consequence. However, they can become symptomatic and cause knee pain. In this review, we will discuss medial plica syndrome. Medial plica irritation of the knee is a common source of anterior knee pain. The main complaint is an intermittent, dull, aching pain in the area medial to the patella above the joint line and in the supramedial patellar area. Pain increases with activity, especially when knee flexion and extension are required. Treatment includes physiotherapy, reducing activity, and rest. In cases that do not respond initially to an exercise program, corticosteroid injections and non-steroidal antiinflammatory medication are given. Results of conservative treatment seem to be more appropriate in young patients with a short duration of symptoms. If conservative treatment fails, surgical treatment using arthroscopy is appropriate. During arthroscopy, excision of the whole plica should be achieved.

  4. 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

  5. Meniscal Allograft Interposition Combined with Proximal Row Carpectomy.

    PubMed

    Steiner, Murphy M; Willsey, Matthew R; Werner, Frederick W; Harley, Brian J; Klein, Shay; Setter, Kevin J

    2017-02-01

    Background Proximal row carpectomy (PRC) is contraindicated in wrists with preexisting arthritis of the proximal capitate or radiolunate fossa. Patients with these conditions frequently pursue wrist arthrodesis with its associated functional limitations. Questions/Purposes The purpose of this study was to evaluate the results of using lateral meniscal allograft interposition (LMAI), in combination with PRC, in patients with symptomatic wrist arthritis. The primary question is whether this allograft will allow wrist function comparable to that in patients having only a PRC. A secondary question was to determine the short-term longevity of the allograft. Patients/Method Between 2006 and 2012, nine wrists underwent PRC with LMAI. Patient demographics and rates of complication or graft failure were determined. During independent clinical exams, functional outcomes were reviewed, patients completed a Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and radiographs were taken. Results Four patients met the inclusion criteria, having clinical follow-up at an average of 4.2 years. DASH scores at the time of follow-up ranged from 9 to 33, with an average of 24. Average radiocapitate joint space in the first postoperative radiograph was 2.8 mm compared with 1.8 mm at the time of final follow-up. No wrists went on to arthrodesis. Conclusion Early outcomes of PRC with LMAI are comparable to those results found in the literature of PRC alone. LMAI with PRC may be a valid short-term option as a motion-preserving procedure in those patients contraindicated to having a PRC alone. Level of Evidence Level IV.

  6. 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

  7. 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.

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

    PubMed

    Kamiński, Jan; Sullivan, Shannon; Chung, Jeffrey M; Ross, Ian B; Mamelak, Adam N; Rutishauser, Ueli

    2017-04-01

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

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

    PubMed Central

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

    2017-01-01

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

  10. A Reduction Method for All-Inside Posterior Horn Meniscal Repair

    PubMed Central

    M. Thompson, Simon; A. Pinczewski, Leo

    2015-01-01

    Obtaining, and maintaining, optimal reduction of a displaced posterior horn can be a difficult and time-consuming procedure. There are many different ways to repair a tear of the meniscus; we describe a quick and simple technique using a readily available meniscal suturing device. PMID:26697298

  11. Stem cell delivery in tissue-specific hydrogel enabled meniscal repair in an orthotopic rat model.

    PubMed

    Yuan, Xiaoning; Wei, Yiyong; Villasante, Aránzazu; Ng, Johnathan J D; Arkonac, Derya E; Chao, Pen-Hsiu Grace; Vunjak-Novakovic, Gordana

    2017-04-04

    Interest in non-invasive injectable therapies has rapidly risen due to their excellent safety profile and ease of use in clinical settings. Injectable hydrogels can be derived from the extracellular matrix (ECM) of specific tissues to provide a biomimetic environment for cell delivery and enable seamless regeneration of tissue defects. We investigated the in situ delivery of human mesenchymal stem cells (hMSCs) in decellularized meniscus ECM hydrogel to a meniscal defect in a nude rat model. First, decellularized meniscus ECM hydrogel retained tissue-specific proteoglycans and collagens, and significantly upregulated expression of fibrochondrogenic markers by hMSCs versus collagen hydrogel alone in vitro. The meniscus ECM hydrogel in turn supported delivery of hMSCs for integrative repair of a full-thickness defect model in meniscal explants after in vitro culture and in vivo subcutaneous implantation. When applied to an orthotopic model of meniscal injury in nude rat, hMSCs in meniscus ECM hydrogel were retained out to eight weeks post-injection, contributing to tissue regeneration and protection from joint space narrowing, pathologic mineralization, and osteoarthritis development, as evidenced by macroscopic and microscopic image analysis. Based on these findings, we propose the use of tissue-specific meniscus ECM-derived hydrogel for the delivery of therapeutic hMSCs to treat meniscal injury.

  12. An evaluation of meniscal collagenous structure using optical projection tomography

    PubMed Central

    2013-01-01

    Background The collagenous structure of menisci is a complex network of circumferentially oriented fascicles and interwoven radially oriented tie-fibres. To date, examination of this micro- architecture has been limited to two-dimensional imaging techniques. The purpose of this study was to evaluate the ability of the three-dimensional imaging technique; optical projection tomography (OPT), to visualize the collagenous structure of the meniscus. If successful, this technique would be the first to visualize the macroscopic orientation of collagen fascicles in 3-D in the meniscus and could further refine load bearing mechanisms in the tissue. OPT is an imaging technique capable of imaging samples on the meso-scale (1-10 mm) at a micro-scale resolution. The technique, similar to computed tomography, takes two-dimensional images of objects from incremental angles around the object and reconstructs them using a back projection algorithm to determine three-dimensional structure. Methods Bovine meniscal samples were imaged from four locations (outer main body, femoral surface, tibial surface and inner main body) to determine the variation in collagen orientation throughout the tissue. Bovine stifles (n = 2) were obtained from a local abattoir and the menisci carefully dissected. Menisci were fixed in methanol and subsequently cut using a custom cutting jig (n = 4 samples per meniscus). Samples were then mounted in agarose, dehydrated in methanol and subsequently cleared using benzyl alcohol benzyl benzoate (BABB) and imaged using OPT. Results Results indicate circumferential, radial and oblique collagenous orientations at the contact surfaces and in the inner third of the main body of the meniscus. Imaging identified fascicles ranging from 80-420 μm in diameter. Transition zones where fascicles were found to have a woven or braided appearance were also identified. The outer-third of the main body was composed of fascicles oriented predominantly in the

  13. Does meniscal pathology alter gait knee biomechanics and strength post-ACL reconstruction?

    PubMed

    Hall, Michelle; Bryant, Adam L; Wrigley, Tim V; Pratt, Clare; Crossley, Kay M; Whitehead, Tim S; Morris, Hayden G; Clark, Ross A; Perraton, Luke G

    2016-05-01

    Individuals following anterior cruciate ligament reconstruction (ACLR) with concomitant meniscal pathology have a higher risk of developing knee osteoarthritis (OA) compared to those with isolated ACLR. Knee extensor weakness and altered dynamic knee joint biomechanics have been suggested to play a role in the development of knee OA following ACLR. This study investigated whether these factors differ in people following ACLR who have concomitant meniscal pathology compared to patients with isolated ACLR. Thirty-three patients with isolated ACLR and 34 patients with ACLR and meniscal pathology underwent strength and gait assessment 12-24 months post-operatively. Primary measures were peak isometric knee extensor torque and knee adduction moment (peak and impulse). Secondary measures included peak knee flexion moment and knee kinematics (sagittal and transverse). There were no between-group differences in knee extensor strength [mean difference (95 % CI) 0.09 (-0.23 to 0.42) Nm/kg, n.s.], peak knee adduction moment [-0.02 (-0.54 to 0.49) Nm/(BW × HT) %, n.s.] or knee adduction moment impulse [0.01 (-0.15 to 0.17) Nm/(BW × HT) %, p = n.s.]. No between-group differences were found for any secondary measures. No evidence was found to suggest that the higher prevalence of OA in patients with ACLR and meniscal pathology compared to patients with isolated ACLR is attributed to reduced knee muscle strength or altered knee joint biomechanics assessed 1-2 years post-surgery. Given that there is a higher incidence of knee OA in patients with concomitant meniscal pathology and ACLR, further investigation is needed so that population-specific rehabilitation protocols can be developed. III.

  14. Variables Associated with Chondral and Meniscal Injuries in Anterior Cruciate Ligament Surgery.

    PubMed

    Cain, E Lyle; Fleisig, Glenn S; Ponce, Brent A; Boohaker, Hikel A; George, Martha P; McGwin, Gerald; Andrews, James R; Lemak, Lawrence J; Clancy, William G; Dugas, Jeffrey R

    2017-09-01

    This article aims to evaluate factors associated with chondral and meniscal lesions in primary and revision anterior cruciate ligament (ACL) reconstructions. ACL reconstructions from 2001 to 2008 at a single institution were retrospectively analyzed. Logistic regression was used to estimate the association between chondral and meniscal injuries and age, gender, tear chronicity, additional ligamentous injuries, sport type, and participation level. Of the 3,040 ACL reconstructions analyzed, 90.4% were primary reconstructions and 9.6% were revisions. Meniscal injuries were significantly lower in the revision group (44.0 vs. 51.9%; p = 0.01), while chondral injuries were significantly higher in the revision group (39.9 vs. 24.0%; p < 0.0001). Inspection of the small subgroup (n = 85) receiving both primary and revision ACL surgery at our center indicated that meniscal injuries at revision were evenly split between menisci with and without previous repairs, whereas the vast majority of Grade III and IV chondral lesions were new. More patients presented for surgery later in the revision group than in the primary group (56.5 vs. 35.3%; p < 0.0001). Male gender, primary reconstruction, and short interval (less than 2 weeks) between injury and surgery were associated with increased likelihood of meniscus tear. Age (greater than 22 years) and long interval (greater than 6 weeks) between injury to surgery and higher sport activity level were associated with chondral lesions. Revision ACL reconstructions are associated with a higher proportion of chondral lesions and a lower proportion of meniscal tears. Early primary and revision ACL construction is recommended to reduce the probability of chondral lesions. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. The accuracy of magnetic resonance imaging (MRI) in detecting meniscal pathology.

    PubMed

    Chambers, S; Cooney, A; Caplan, N; Dowen, D; Kader, D

    2014-01-01

    The purpose of this study was to determine the accuracy of Magnetic Resonance Imaging (MRI) scanning in the detection of meniscal pathology in a district general hospital. We retrospectively analysed a single-surgeon series of 240 knee arthroscopic investigations for all indications. The arthroscopic reports included an outline diagram of the meniscus upon which the surgeon could record his operative findings. 112 of these patients had also had a recent MRI scan. We compared the MRI findings with the arthroscopy findings. 66 patients had a positive MRI scan. 64 of these were found to have a meniscal tear at surgery. 37 MRI scans were reported as "no tear", of which four were found to have a meniscal tear at surgery. Nine MRI scans were descriptive, e.g. "signal change, possible tear", or "tear cannot be ruled out." These tended to correspond with equivocal arthroscopic findings of "degeneration" or "fibrillation". In our series of 112 patients with meniscal pathology, MRI scanning was 90.5% sensitive, 89.5% specific and 90.1% accurate. False positive MRI scans may lead to unnecessary surgery. Patients with negative MRI scans had a mean delay to surgery of 33 weeks compared to 18 weeks for patients with positive MRI scans. Patients with false negative MRI results may wait longer for their surgery. Two of the false negative MRI scan reports clearly showed meniscus tears, which were not identified by the reporting radiologist. In our series, the MRI scan itself was more accurate than the reporting. It is important to have an experienced musculoskeletal radiologist to minimise the number of missed meniscal tears. It is also important for the surgeon to review the MRI scan itself, as well as the report.

  16. Three-dimensional culture of human meniscal cells: Extracellular matrix and proteoglycan production

    PubMed Central

    Gruber, Helen E; Mauerhan, David; Chow, Yin; Ingram, Jane A; Norton, H James; Hanley, Edward N; Sun, Yubo

    2008-01-01

    Background The meniscus is a complex tissue whose cell biology has only recently begun to be explored. Published models rely upon initial culture in the presence of added growth factors. The aim of this study was to test a three-dimensional (3D) collagen sponge microenvironment (without added growth factors) for its ability to provide a microenvironment supportive for meniscal cell extracellular matrix (ECM) production, and to test the responsiveness of cells cultured in this manner to transforming growth factor-β (TGF-β). Methods Experimental studies were approved prospectively by the authors' Human Subjects Institutional Review Board. Human meniscal cells were isolated from surgical specimens, established in monolayer culture, seeded into a 3D scaffold, and cell morphology and extracellular matrix components (ECM) evaluated either under control condition or with addition of TGF-β. Outcome variables were evaluation of cultured cell morphology, quantitative measurement of total sulfated proteoglycan production, and immunohistochemical study of the ECM components chondroitin sulfate, keratan sulfate, and types I and II collagen. Result and Conclusion Meniscal cells attached well within the 3D microenvironment and expanded with culture time. The 3D microenvironment was permissive for production of chondroitin sulfate, types I and II collagen, and to a lesser degree keratan sulfate. This microenvironment was also permissive for growth factor responsiveness, as indicated by a significant increase in proteoglycan production when cells were exposed to TGF-β (2.48 μg/ml ± 1.00, mean ± S.D., vs control levels of 1.58 ± 0.79, p < 0.0001). Knowledge of how culture microenvironments influence meniscal cell ECM production is important; the collagen sponge culture methodology provides a useful in vitro tool for study of meniscal cell biology. PMID:18582376

  17. Masseter and medial pterygoid muscle hypertrophy.

    PubMed

    Guruprasad, R; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-09-26

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination are important in differentiating this benign condition from parotid or dental pathology, they cannot necessarily exclude rare malignant lesion within the muscle. Advanced imaging modalities like CT and MRI are essential to confirm the diagnosis. Here the authors are reporting a unique case of masseter muscle hypertrophy along with medial pterygoid hypertrophy which was missed clinically but confirmed using CT and MRI.

  18. Masseter and medial pterygoid muscle hypertrophy

    PubMed Central

    R, Guruprasad; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-01-01

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination are important in differentiating this benign condition from parotid or dental pathology, they cannot necessarily exclude rare malignant lesion within the muscle. Advanced imaging modalities like CT and MRI are essential to confirm the diagnosis. Here the authors are reporting a unique case of masseter muscle hypertrophy along with medial pterygoid hypertrophy which was missed clinically but confirmed using CT and MRI. PMID:22679271

  19. The quantitative evaluation of the impact of viable medial meniscus graft type on the biochemical and biomechanical properties of the rabbit tibial cartilage.

    PubMed

    Zwierzchowski, Tomasz J; Janus, Jolanta; Konecki, Włodzimierz; Kubiak, Grzegorz; Fabiś, Jarosław

    2015-11-12

    Knowledge of the impact of viable medial meniscus allograft and autograft transplantation on biochemical and mechanical properties of cartilage is needed to understand the development of joint osteoarthritis. The purpose of this study was to evaluate this relationship 6 months after viable medial meniscal autograft and allograft transplantation. Twenty rabbits were chosen for the study. The medial menisci were excised from 14 animals and stored under tissue culture conditions for 2 weeks. Seven menisci were implanted as autografts (group A) and seven as allografts (group B). The control group consisted of six animals which underwent arthrotomy. The tibial cartilage was used for mechanical and biochemical evaluation. The respective decreases of glycosaminoglycans (GAGs) and elasticity were 13.4 and 14.8% for group A and 30.4 and 32.6% for group B. The differences between group A and B and between each group and the control were statistically significant. The total collagen content was significantly lower in group B. The type of viable meniscal graft has an influence on the biochemical composition of the extracellular matrix (ECM) and biomechanical properties of the underlying tibial cartilage. A 1% decrease of glycosaminoglycan content is associated with a 1.1% decrease of cartilage elasticity. The average ratio of decrease of cartilage elasticity to that of the meniscus was 0.77 regardless of the type of meniscus graft. The viable allograft causes irreversible ECM disorder of the cartilage. Knowledge of the biochemical composition of the ECM meniscal grafts may serve as a predictor of their chondroprotective properties.

  20. Mouse models of osteoarthritis: surgical model of posttraumatic osteoarthritis induced by destabilization of the medial meniscus.

    PubMed

    Culley, Kirsty L; Dragomir, Cecilia L; Chang, Jun; Wondimu, Elisabeth B; Coico, Jonathan; Plumb, Darren A; Otero, Miguel; Goldring, Mary B

    2015-01-01

    The surgical model of destabilization of the medial meniscus (DMM) has become a gold standard for studying the onset and progression of posttraumatic osteoarthritis (OA). The DMM model mimics clinical meniscal injury, a known predisposing factor for the development of human OA, and permits the study of structural and biological changes over the course of the disease. In addition, when applied to genetically modified or engineered mouse models, this surgical procedure permits dissection of the relative contribution of a given gene to OA initiation and/or progression. This chapter describes the requirements for the surgical induction of OA in mouse models, and provides guidelines and tools for the subsequent histological, immunohistochemical, and molecular analyses. Methods for the assessment of the contributions of selected genes in genetically modified strains are also provided.

  1. Arthroscopic Direct Repair for a Complete Radial Tear of the Posterior Root of the Medial Meniscus

    PubMed Central

    Wang, Kook Hyun; Hwang, Dae Hee; Cho, Jin Ho; Changale, Sachin D.; Woo, Sung Jong

    2011-01-01

    We report here on a new arthroscopic direct repair technique for a radial tear of the posterior root of the medial meniscus (PRMM) using a posterior trans-septal portal. Radial tears of the PRMM are commonly observed in the elderly population of Korea and Japan, and the life style of these people requires squatting and kneeling down in daily life. A radial tear of the PRMM results in the loss of hoop tension and this accelerates degenerative changes in the knee joint and causes early osteoarthritis. Several reports in the medical literature have focused on various repair techniques for these tears by using pull out sutures. These techniques result in nonanatomic fixation of the meniscus, which may lead to disturbed meniscal excursion and failure to restore hoop tension. Arthroscopic direct repair may contribute to restoring hoop tension and preventing accelerated degenerative changes in the knee joint of these patients. PMID:22162797

  2. A clinical prediction rule for meniscal tears in primary care: development and internal validation using a multicentre study

    PubMed Central

    Snoeker, Barbara AM; Zwinderman, Aeilko H; Lucas, Cees; Lindeboom, Robert

    2015-01-01

    Background In primary care, meniscal tears are difficult to detect. A quick and easy clinical prediction rule based on patient history and a single meniscal test may help physicians to identify high-risk patients for referral for magnetic resonance imaging (MRI). Aim The study objective was to develop and internally validate a clinical prediction rule (CPR) for the detection of meniscal tears in primary care. Design and setting In a cross-sectional multicentre study, 121 participants from primary care were included if they were aged 18–65 years with knee complaints that existed for <6 months, and who were suspected to suffer from a meniscal tear. Method One diagnostic physical meniscal test and 14 clinical variables were considered to be predictors of MRI outcome. Using known predictors for the presence of meniscal tears, a ‘quick and easy’ CPR was derived. Results The final CPR included the variables sex, age, weight-bearing during trauma, performing sports, effusion, warmth, discolouration, and Deep Squat test. The final model had an AUC of 0.76 (95% CI = 0.72 to 0.80). A cut-point of 150 points yielded an overall sensitivity of 86.1% and a specificity of 45.5%. For this cut-point, the positive predictive value was 55.0%, and the negative predictive value was 81.1%. A scoring system was provided including the corresponding predicted probabilities for a meniscal tear. Conclusion The CPR improved the detection of meniscal tears in primary care. Further evaluation of the CPR in new primary care patients is needed, however, to assess its usefulness. PMID:26212848

  3. 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

  4. [Focal cartilage defects within the medial knee compartment. predictors for osteoarthritis progression].

    PubMed

    Spahn, G; Hofmann, G O

    2014-10-01

    The aim of this study was to evaluate the progression of osteoarthritis (end-stage disease with a requirement for arthroplasty) in patients with focal cartilage defects of the medial knee compartment. Patients (n = 115) with focal cartilage lesions of the medial knee compartment underwent arthroscopy. The follow-up was performed 10 years after the operation to determine the rate of arthroplasty conversion and to evaluate associated factors. In a total of 35 cases an arthroplasty was needed (30.4 %). The mean survival to arthroplasty was 93.2 (95 % CI 85.4-109.0) months. Cartilage defects within the femur and cartilage lesions within the patella and the lateral did not influence the OA progression. Among the significant risk factors for OA progression were higher patient age, female gender, overweight or obesity and severity of meniscal damage. The most important risk factor was the occurrence and the extent of tibial cartilage defects. In the natural course, about 30 % of patients with focal cartilage defects of the medial knee compartment undergo rapid OA progression (arthroplasty as end-stage of the disease). There are general risk factors (age, female gender and obesity) but also local risk factors. Furthermore, tibial defects and the extent of meniscus loss influence the outcome significantly. These general and local factors should be more carefully estimated or addressed in future clinical and scientific work. Georg Thieme Verlag KG Stuttgart · New York.

  5. Selenium Reduces Early Signs of Tumor Necrosis Factor Alpha-Induced Meniscal Tissue Degradation.

    PubMed

    Häfelein, Klaus; Preuße-Prange, Andrea; Behrendt, Peter; Kurz, Bodo

    2017-05-01

    Meniscal integrity is a prerequisite for sustained knee joint health and prevention of meniscal degeneration is a main research goal. Cartilage-protective effects of selenium have been described, but little is known about the impact on the meniscus. We therefore investigated the influence of sodium selenite on meniscal explants under tumor necrosis factor-alpha (TNFα)-stimulated proinflammatory conditions. Meniscal explant disks (3 mm diameter × 1 mm thickness) were isolated from 2-year-old cattle and incubated with TNFα (10 ng/ml) and sodium selenite (low dose, LoD 6.7 ng/ml as being found in Insulin-Transferrin-Selenium medium supplements, ITS; medium-dose, MeD 40 ng/ml described as physiological synovial concentration; high dose, HiD 100 ng/ml described as optimal serum concentration). After 3 days of culture glycosaminoglycan (GAG) release (DMMB assay), nitric oxide (NO) production (Griess assay), gene expression of matrix-degrading enzymes (quantitative RT-PCR), and apoptosis rate were determined. TNFα led to a significant raise of GAG release and NO production. LoD and MeD selenite significantly reduced the TNFα-induced GAG release (by 83, 55 %, respectively), NO production (by 59, 40 %, respectively), and apoptosis (by 68, 39 %, respectively). LoD and MeD selenite showed a tendency to reduce the TNFα-mediated increase of inducible NO-synthase (iNOS) levels, LoD selenite furthermore matrix metalloproteinase (MMP)-3 transcription levels and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 levels. LoD and less pronounced MeD selenite show a substantial impact on the early meniscal inflammatory response. To our knowledge this is the first study showing the protective influence of selenium on meniscal tissue maintenance. To understand the superior potency of low-dose selenium on molecular level future studies are needed.

  6. Differential involvement of medial prefrontal cortex and basolateral amygdala extracellular signal-regulated kinase in extinction of conditioned taste aversion is dependent on different intervals of extinction following conditioning.

    PubMed

    Lin, P-Y; Wang, S-P; Tai, M-Y; Tsai, Y-F

    2010-11-24

    Extinction reflects a decrease in the conditioned response (CR) following non-reinforcement of a conditioned stimulus. Behavioral evidence indicates that extinction involves an inhibitory learning mechanism in which the extinguished CR reappears with presentation of an unconditioned stimulus. However, recent studies on fear conditioning suggest that extinction erases the original conditioning if the time interval between fear acquisition and extinction is short. The present study examined the effects of different intervals between acquisition and extinction of the original memory in conditioned taste aversion (CTA). Male Long-Evans rats acquired CTA by associating a 0.2% sucrose solution with malaise induced by i.p. injection of 4 ml/kg 0.15 M LiCl. Two different time intervals, 5 and 24 h, between CTA acquisition and extinction were used. Five or 24 h after CTA acquisition, extinction trials were performed, in which a bottle containing 20 ml of a 0.2% sucrose solution was provided for 10 min without subsequent LiCl injection. If sucrose consumption during the extinction trials was greater than the average water consumption, then rats were considered to have reached CTA extinction. Rats subjected to extinction trials lasting 24 h, but not 5 h, after acquisition re-exhibited the extinguished CR following injection of 0.15 M LiCl alone 7 days after acquisition. Extracellular signal-regulated kinase (ERK) in the medial prefrontal cortex (mPFC) and basolateral nucleus of the amygdala (BLA) was examined by Western blot after the first extinction trial. ERK activation in the mPFC was induced after the extinction trial beginning 5 h after acquisition, whereas the extinction trial performed 24 h after acquisition induced ERK activation in the BLA. These data suggest that the original conditioning can be inhibited or retained by CTA extinction depending on the time interval between acquisition and extinction and that the ERK transduction pathway in the mPFC and BLA is

  7. Potential use of mesenchymal stem cells in human meniscal repair: current insights

    PubMed Central

    Pak, Jaewoo; Lee, Jung Hun; Park, Kwang Seung; Jeon, Jeong Ho; Lee, Sang Hee

    2017-01-01

    The menisci of the human knee play an important role in maintaining normal functions to provide stability and nutrition to the articular cartilage, and to absorb shock. Once injured, these important structures have very limited natural healing potential. Unfortunately, the traditional arthroscopic meniscectomy performed on these damaged menisci may predispose the joint toward early development of osteoarthritis. Although a very limited number of studies are available, mesenchymal stem cells (MSCs) have been investigated as an alternative therapeutic modality to repair human knee meniscal tears. This review summarizes the results of published applications of MSCs in human patients, which showed that the patients who received MSCs (autologous adipose tissue-derived stem cells or culture-expanded bone marrow-derived stem cells) presented symptomatic improvements, along with magnetic resonance imaging evidences of the meniscal repair. PMID:28356779

  8. The MeTeOR trial (Meniscal Tear in Osteoarthritis Research): rationale and design features.

    PubMed

    Katz, Jeffrey N; Chaisson, Christine E; Cole, Brian; Guermazi, Ali; Hunter, David J; Jones, Morgan; Levy, Bruce A; Mandl, Lisa A; Martin, Scott; Marx, Robert G; Safran-Norton, Clare; Roemer, Frank W; Skoniecki, Debra; Solomon, Daniel H; Spindler, Kurt P; Wright, John; Wright, Rick W; Losina, Elena

    2012-11-01

    This paper presents the rationale and design features of the MeTeOR Trial (Meniscal Tear in Osteoarthritis Research; Clinical Trials.gov NCT00597012). MeTeOR is an NIH-funded seven-center prospective randomized controlled trial (RCT) designed to establish the efficacy of arthroscopic partial meniscectomy combined with a standardized physical therapy program as compared with a standardized physical therapy program alone in patients with a symptomatic meniscal tear in the setting of mild to moderate knee osteoarthritic change (OA). The design and execution of a trial that compares surgery with a nonoperative treatment strategy presents distinctive challenges. The goal of this paper is to provide the clinical rationale for MeTeOR and to highlight salient design features, with particular attention to those that present clinical and methodologic challenges.

  9. 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

  10. Arthroscopic partial meniscectomy is superior to physical rehabilitation in the management of symptomatic unstable meniscal tears.

    PubMed

    El Ghazaly, Sherif A; Rahman, Amr A Abdul; Yusry, Ahmed H; Fathalla, Mahmoud M

    2015-04-01

    Meniscus injuries are the most commonly reported in athletes. Meniscectomy is the most common treatment. Stable peripheral tears may heal, while degenerative tears do well with physical therapy. However, the exact role of physical therapy in treating symptomatic unstable meniscal tears is not known. We aimed to identify the role of physical therapy in treating such patients and clarify the role of arthroscopic partial meniscectomy in treating unstable meniscal tears. Seventy patients with unstable meniscal tear met the inclusion criteria according to Vande Berg and co-workers. Clinical examination, McMurray test and magnetic resonance imaging were done. Age ranged from 18-67 years (average 39.87). Mild osteoarthritis was seen in 20 cases. Physical therapy thrice a week for eight weeks was offered (faradic quadriceps stimulation and neuromuscular strengthening exercises). After physical therapy, patients still complaining or unsatisfied were offered arthroscopic partial menisectomy (APM). Outcomes were evaluated using the VAS pain score and the Lysholm knee score. Mean VAS before interventions was 7.4, significantly improved to 5.16 after rehabilitation and to 1.9 after APM (p = 0.001). Mean Lysholm score before rehabilitation was 65.1 and improved to 69.6 after rehabilitation, the difference was non-significant. However, Lysholm score difference before and after APM showed a highly significant difference (p = 0.001). Pain and swelling improved after physical therapy. However, patients were not satisfied as limited range of knee motion persisted. APM was superior to physical therapy in treating symptomatic unstable meniscal tears, with high patient satisfaction and restored knee function.

  11. Congenital dystrophic medial rectus muscles

    PubMed Central

    Murthy, Ramesh

    2017-01-01

    We report two patients, one with congenital dystrophic medial rectus muscles and one with absence of the medial rectus muscles; in addition, one of them had absence of the lateral rectus muscles. While absence of the superior oblique and superior rectus has been more commonly reported in literature, especially with craniofacial syndromes, our patients were nonsyndromic. Considering the risk of anterior segment ischemia, correction of the large-angle exotropia was performed by horizontal rectus muscle surgery where possible, along with transfer of the superior oblique tendon to the superior part of the normal medial rectus muscle insertion area to create a tethering effect with a good outcome. PMID:28300745

  12. Isolated arthroscopic meniscal repair: a long-term outcome study (more than 10 years).

    PubMed

    Johnson, M J; Lucas, G L; Dusek, J K; Henning, C E

    1999-01-01

    A single surgeon's consecutive series of 50 arthroscopically repaired meniscal tears in 48 patients was retrospectively reviewed. None of these patients had concomitant ligament damage to the knee. The average follow-up period was 10 years, 9 months. Criteria for clinical success included 1) history of pain of grade 1 or less and absence of locking, catching, or giving way; 2) a physical examination demonstrating no significant effusion and a painless and negative jump sign; and 3) no subsequent surgical procedures on the repaired meniscus. Patient satisfaction was quite high, although clinical confirmation was possible in only 38 knees, indicating a clinical success rate of 76%. Bilateral standing radiographs were obtained on these 38 operated knees and were evaluated using Fairbank's classification. Evaluation of the radiographs revealed that 8% of the operated knees had minimal joint changes, as compared with 3% in the contralateral, nonoperated knee. This study demonstrates that arthroscopic meniscal repair in knees with isolated meniscal tears has the potential for a long-term successful clinical and radiographic outcome.

  13. Formation of vascularized meniscal tissue by combining gene therapy with tissue engineering.

    PubMed

    Hidaka, Chisa; Ibarra, Clemente; Hannafin, Jo A; Torzilli, Peter A; Quitoriano, Mannix; Jen, Shih-Shi; Warren, Russell F; Crystal, Ronald G

    2002-02-01

    Ingrowth of host blood vessels into engineered tissues has potential benefits for successful transplantation of engineered tissues as well as healing of surrounding host tissues. In particular, the use of a vascularized bioengineered tissue could be beneficial for treating injuries to the meniscus, a structure in the knee where the lack of a vascular supply is associated with an inadequate healing response. In this study, gene transfer using an adenovirus vector encoding the hepatocyte growth factor gene (AdHGF) was used to induce blood vessel formation in tissue-engineered meniscus. Bovine meniscal cells were treated with AdHGF, a vector encoding a marker gene E. coli beta-galactosidase (Adbetagal), or no virus. Cells were seeded onto poly-glycolic acid felt scaffolds and then transplanted into the subcutaneous pouch of athymic nude mice for 8 weeks. Expression of the marker gene and HGF was detectable for several weeks after gene transfer. Ink injection studies showed that AdHGF-treated meniscal cells formed tissue which contained fourfold more blood vessels at 2 weeks (p < 0.02) and 2.5-fold more blood vessels at 8 weeks (p < 0.001) posttransplantation than controls. This study demonstrates the feasibility of using adenovirus-mediated gene transfer to engineer a blood supply in the bioengineered meniscal tissue.

  14. Translation and Validation of the Dutch Western Ontario Meniscal Evaluation Tool.

    PubMed

    van der Wal, Robert J P; Heemskerk, Bastiaan T J; van Arkel, Ewoud R A; Mokkink, Lidwine B; Thomassen, Bregje J W

    2017-05-01

    The aim of this study was to translate the Western Ontario Meniscal Evaluation Tool (WOMET) into Dutch, to evaluate the content validity, construct validity, reliability, and responsiveness, and to determine the minimal important change (MIC) of the Dutch version. The WOMET was translated into Dutch according to a standardized forward-backward translation protocol. A total of 86 patients (51 males, 35 females, median age 52 years [interquartile range, 43-60 years]) with isolated meniscal pathology were included. The WOMET was completed three times; at baseline, around 2 weeks, and after 3 months from the baseline. Knee injury and osteoarthritis outcome score, International Knee Documentation Committee subjective knee form, short-form 36, and an anchor question were also answered. There were good results for content validity (floor and ceiling effects [< 15%]), construct validity (79% of the predefined hypotheses were confirmed), internal consistency (Cronbach α = 0.87, 0.79, and 0.86 for each subscale score), test-retest reliability (intraclass correlation coefficient = 0.78 for total WOMET score), and responsiveness (79% of the predefined hypotheses were confirmed). The smallest detectable change and MIC for the Dutch WOMET are 20.5 and 14.7, respectively. The Dutch version of the WOMET is valid and reliable for assessing health-related quality of life in patients with meniscal pathology. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. 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.

  16. Medial Patellofemoral Ligament Reconstruction

    PubMed Central

    Palacios, Jose Antonio; Yacuzzi, Carlos; Oñativia, Jose I.; Zicaro, Juan Pablo; Costa-Paz, Matias

    2017-01-01

    Objectives: Recurrent patellofemoral dislocation is usually a multifactorial pathology. Different surgical techniques have been described according to the etiology of dislocation. In absence of a severe malalignment or an anatomical patellofemoral dysplasia, reconstruction of Medial Patello-femoral Ligament (MPFL) can restore the normal tracking of the patella, avoiding lateral excursion. The purpose of this study was to evaluate clinical results and complications in patients who underwent a MPFL reconstruction. Methods: We retrospectively evaluated 19 patients who underwent an anatomic MPFL reconstruction using autologous semitendinosus graft between 2007 and 2012. Exclusion criteria were patients with less than three years of follow-up and those with an associated procedure such as distal realignment or trochleoplasty. Clinical outcomes were measured using Kujala score and return to sport rate. We registered the postoperative complications and recurrence rate. Results: Nine patients were men and 10 women with a mean age of 25 years. Average follow-up was 5.8 years. Nine patients (47.4%) returned to their previous sport level, 8 (42.1%) changed to another sport or decreased their level and 2 (10.5%) were unable to practice any sports at all. Kujala score improvement was from 62.8 preoperative to 88.8 postoperative. One patient decreased the Kujala score. Eighty-nine percent of patients were satisfied with their outcome. One patient had a patellar fracture and four developed an arthrofibrosis and required mobilization under anesthesia. No recurrences were registered. Conclusion: Isolated MPFL reconstruction for recurrent patellofemoral dislocation is an effective alternative in absence of severe malalignment or anatomical dysplasia. Although no recurrences where registered at minimum 3-year follow-up, almost half of the patients were not able to return to their previous sport level.

  17. Traumatic fracture of the medial coronoid process in 24 dogs.

    PubMed

    Tan, Desmond K; Canapp, Sherman O; Leasure, Christopher S; Dycus, David L; O'Donnell, Erica

    2016-07-19

    To describe traumatic fracture of the medial coronoid process in dogs as a clinically distinct disease unrelated to congenital elbow dysplasia. Clinical records of dogs with acute, traumatic, unilateral lameness attributable to medial coronoid process disease were reviewed retrospectively. Clinical interpretation included findings on physical examination, orthopaedic examination, and subjective gait analysis. Radiographs of the affected and contralateral elbows were obtained and reviewed for pathology. Arthroscopy of the elbow joints was performed by one of three surgeons and findings were compared to preoperative diagnostics. Postoperative follow-up was continued for 16 weeks. Twenty-four dogs were included in this study. All dogs in this study were free of radiographic evidence of medial coronoid pathology. All dogs were diagnosed with a single, large, displaced or non-displaced fracture of the medial coronoid process, with no other joint pathology. Dogs generally had an excellent short-term outcome following arthroscopic treatment of the fractured medial coronoid process. Traumatic fracture of the medial coronoid process should be considered a clinical disease distinct from dysplasia-related fragmentation and should be considered as a differential diagnosis in dogs that are presented with the complaint of acute unilateral elbow discomfort or lameness, especially after concussive activities involving the forelimb. .

  18. Return to play after all-inside meniscal repair in competitive football players: a minimum 5-year follow-up.

    PubMed

    Alvarez-Diaz, Pedro; Alentorn-Geli, Eduard; Llobet, Federico; Granados, Nelson; Steinbacher, Gilbert; Cugat, Ramón

    2016-06-01

    The purpose of this study was to report the mid-to-long-term return to sports after all-inside meniscal repair in competitive football players. All football players undergoing all-inside meniscal repair with a minimum Tegner activity score of 9 and minimum follow-up of 5 years were eligible for inclusion. Patients were excluded if: (a) they had ipsilateral or contralateral: meniscectomy, posterior cruciate ligament tear, multi-ligament knee injuries, osteotomies, or meniscal transplant (b) they had meniscal tears in the anterior horn, and (c) they had bucket-handle tears. All patients included were contacted by phone and asked for current sport status or Tegner score. Preoperative Tegner scores were collected from the medical charts. All patients (n = 29) were men with a median (range) age of 27 (18-37) years and a follow-up of 6 (5-8) years. All meniscal injuries were complete and longitudinal tears. The median preinjury Tegner activity score was 9 (range 9-10). Two patients required revision arthroscopy (6.7 %) with partial meniscectomy before being able to return to competitive football due to suture failure. Twenty-six patients (89.6 %) returned to the same level of competition after recovering from surgery. At the last follow-up, 13 patients (45 %) were able to continue playing football at any level, and 8 (28 %) of them were able to return to the same pre-injury competitive level. The main reasons for the decreased level of activity (from competitive to recreational) or to give up football were job-related or changes in their personal life situation, but were not related to knee or meniscal disorders. Fourteen patients underwent meniscal repair alone, whereas 15 patients had an associated ACL reconstruction procedure. There were no significant differences in the collected variables between both subgroups. All-inside meniscal repair allows for excellent results with regard to return-to-play rates in competitive football. However, only half of the

  19. Platelet-Rich Fibrin Facilitates Rabbit Meniscal Repair by Promoting Meniscocytes Proliferation, Migration, and Extracellular Matrix Synthesis

    PubMed Central

    Wong, Chin-Chean; Kuo, Tzong-Fu; Yang, Tsung-Lin; Tsuang, Yang-Hwei; Lin, Ming-Fang; Chang, Chung-Hsun; Lin, Yun-Ho

    2017-01-01

    Although platelet-rich fibrin (PRF) has been used in clinical practice for some time, to date, few studies reveal its role as a bioactive scaffold in facilitating meniscal repair. Here, the positive anabolic effects of PRF on meniscocytes harvested from the primary culture of a rabbit meniscus were revealed. The rabbit meniscocytes were cultured with different concentrations of PRF-conditioned medium, and were evaluated for their ability to stimulate cell migration, proliferation, and extracellular matrix formation. In vivo, meniscal defects were created via an established rabbit animal model and were evaluated by a histology-based four-stage scoring system to validate the treatment outcome three months postoperatively. The in vitro results showed that PRF could induce cellular migration and promote proliferation and meniscocyte extracellular matrix (ECM) synthesis of cultured meniscocytes. In addition, PRF increased the formation and deposition of cartilaginous matrix produced by cultured meniscocytes. Morphological and histological evaluations demonstrated that PRF could facilitate rabbit meniscal repair. The data highlight the potential utility of using PRF in augmenting the healing of meniscal injuries. These advantages would benefit clinical translation, and are a potential new treatment strategy for meniscal repair. PMID:28783120

  20. 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.

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

    PubMed

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

    1986-12-01

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

  2. The vertical medial thigh lift.

    PubMed

    Capella, Joseph F

    2014-10-01

    This article discusses management of the post-weight loss thigh deformity. Beginning with an explanation of the soft tissue variables contributing to the thigh and medial thigh deformity in the postbariatric individual, the article describes the important elements of selecting and screening candidates for surgery and the ideal sequence of procedures that should be followed to optimize results in this patient population. A detailed step-by-step description of the author's technique for medial thigh lift is provided along with multiple examples of outcomes. Aftercare is reviewed along with potential complications and their management. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. A novel quantitative approach for evaluating contact mechanics of meniscal replacements.

    PubMed

    Linder-Ganz, E; Elsner, J J; Danino, A; Guilak, F; Shterling, A

    2010-02-01

    One of the functions of the meniscus is to distribute contact forces over the articular surfaces by increasing the joint contact areas. It is widely accepted that total/partial loss of the meniscus increases the risk of joint degeneration. A short-term method for evaluating whether degenerative arthritis can be prevented or not would be to determine if the peak pressure and contact area coverage of the tibial plateau (TP) in the knee are restored at the time of implantation. Although several published studies already utilized TP contact pressure measurements as an indicator for biomechanical performance of allograft menisci, there is a paucity of a quantitative method for evaluation of these parameters in situ with a single effective parameter. In the present study, we developed such a method and used it to assess the load distribution ability of various meniscal implant configurations in human cadaveric knees (n=3). Contact pressures under the intact meniscus were measured under compression (1200 N, 0 deg flexion). Next, total meniscectomy was performed and the protocol was repeated with meniscal implants. Resultant pressure maps were evaluated for the peak pressure value, total contact area, and its distribution pattern, all with respect to the natural meniscus output. Two other measures--implant-dislocation and implant-impingement on the ligaments--were also considered. If any of these occurred, the score was zeroed. The total implant score was based on an adjusted calculation of the aforementioned measures, where the natural meniscus score was always 100. Laboratory experiments demonstrated a good correlation between qualitative and quantitative evaluations of the same pressure map outputs, especially in cases where there were contradicting indications between different parameters. Overall, the proposed approach provides a novel, validated method for quantitative assessment of the biomechanical performance of meniscal implants, which can be used in various

  4. Clinical knee findings in floor layers with focus on meniscal status

    PubMed Central

    Rytter, Søren; Jensen, Lilli Kirkeskov; Bonde, Jens Peter

    2008-01-01

    Background The aim of this study was to examine the prevalence of self-reported and clinical knee morbidity among floor layers compared to a group of graphic designers, with special attention to meniscal status. Methods We obtained information about knee complaints by questionnaire and conducted a bilateral clinical and radiographic knee examination in 134 male floor layers and 120 male graphic designers. After the exclusion of subjects with reports of earlier knee injuries the odds ratio (OR) with 95% confidence intervals (CI) of knee complaints and clinical findings were computed among floor layers compared to graphic designers, using logistic regression. Estimates were adjusted for effects of body mass index, age and knee straining sports. Using radiographic evaluations, we conducted side-specific sensitivity analyses regarding clinical signs of meniscal lesions after the exclusion of participants with tibiofemoral (TF) osteoarthritis (OA). Results Reports of knee pain (OR = 2.7, 95% CI = 1.5–4.6), pain during stair walking (OR = 2.2, 95% CI = 1.3–3.9) and symptoms of catching of the knee joint (OR = 2.9, 95% CI = 1.4–5.7) were more prevalent among floor layers compared to graphic designers. Additionally, significant more floor layers than graphic designers had clinical signs suggesting possible meniscal lesions: a positive McMurray test (OR = 2.4, 95% CI = 1.1–5.0) and TF joint line tenderness (OR = 5.4, 95% CI = 2.4–12.0). Excluding floor layers (n = 22) and graphic designers (n = 15) with radiographic TF OA did not alter this trend between the two study groups: a positive McMurray test (OR = 2.2, 95% CI = 1.0–4.9), TF joint line tenderness (OR = 5.0, 95% CI = 2.0–12.5). Conclusion Results indicate that floor layers have a high prevalence of both self-reported and clinical knee morbidity. Clinical knee findings suggesting possible meniscal lesions were significant more prevalent among floor layers compared to a group of low-level exposed graphic

  5. Clinical knee findings in floor layers with focus on meniscal status.

    PubMed

    Rytter, Søren; Jensen, Lilli Kirkeskov; Bonde, Jens Peter

    2008-10-22

    The aim of this study was to examine the prevalence of self-reported and clinical knee morbidity among floor layers compared to a group of graphic designers, with special attention to meniscal status. We obtained information about knee complaints by questionnaire and conducted a bilateral clinical and radiographic knee examination in 134 male floor layers and 120 male graphic designers. After the exclusion of subjects with reports of earlier knee injuries the odds ratio (OR) with 95% confidence intervals (CI) of knee complaints and clinical findings were computed among floor layers compared to graphic designers, using logistic regression. Estimates were adjusted for effects of body mass index, age and knee straining sports. Using radiographic evaluations, we conducted side-specific sensitivity analyses regarding clinical signs of meniscal lesions after the exclusion of participants with tibiofemoral (TF) osteoarthritis (OA). Reports of knee pain (OR = 2.7, 95% CI = 1.5-4.6), pain during stair walking (OR = 2.2, 95% CI = 1.3-3.9) and symptoms of catching of the knee joint (OR = 2.9, 95% CI = 1.4-5.7) were more prevalent among floor layers compared to graphic designers. Additionally, significant more floor layers than graphic designers had clinical signs suggesting possible meniscal lesions: a positive McMurray test (OR = 2.4, 95% CI = 1.1-5.0) and TF joint line tenderness (OR = 5.4, 95% CI = 2.4-12.0). Excluding floor layers (n = 22) and graphic designers (n = 15) with radiographic TF OA did not alter this trend between the two study groups: a positive McMurray test (OR = 2.2, 95% CI = 1.0-4.9), TF joint line tenderness (OR = 5.0, 95% CI = 2.0-12.5). Results indicate that floor layers have a high prevalence of both self-reported and clinical knee morbidity. Clinical knee findings suggesting possible meniscal lesions were significant more prevalent among floor layers compared to a group of low-level exposed graphic designers and an association with occupational

  6. 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.

  7. 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

  8. Evaluation of MRI Versus Arthroscopy in Anterior Cruciate Ligament and Meniscal Injuries

    PubMed Central

    Kashikar, Shivali Vaibhav; Lakhkar, Bhushan Narayan; Ahsan, Mohammad Saleem

    2014-01-01

    Aims and Objectives: To find out the incidence of ACL & meniscal injuries, to co-relate MRI findings with arthroscopy by calculating Sensitivity, Specificity, Positive And Negative Predictive Values (PPV & NPV) keeping arthroscopy as a gold standard, to find out the degree of subluxation and to grade it and to find a threshold value of fluid in knee. Settings and Design: Prospective analytical study. Materials and Methods: MRI of 230 patients with 71 arthroscopic co- relation in year 2012-14 was analysed. Statistical Analysis: Descriptive statistics using Chi square test and predictive values was done. The spearman correlation coefficient was done by using statistical software SPSS 17.0. Results: The sensitivity, specificity, PPV and NPV was calculated (in %). For ACL it was 87.87, 81.57, 80.55, 88.57 for MM 93.54, 87.50, 85.29, 94.59 and for LM 77.77, 81.81, 72.41, 85.71 respectively. We found 35.6% incidence of anterior tibial subluxation with maximum patients having grade 1 category subluxation. Two hundred and one cases showed joint fluid in lateral aspect of the suprapatellar pouch (AP diameter >10mm) with internal derangement. Conclusion: MRI is helpful in diagnosing meniscal and cruciate ligament injuries. Arthroscopy still remains gold standard for definitive diagnosis. PMID:25654007

  9. Relationship between the migratory, metabolic and proliferative ability of fibrochondrocytes and the meniscal fragment size: an in vivo study.

    PubMed

    Dai, Zhu; Li, Kang-Hua; Chen, Zhi-Wei; Hou, Zi-Xin; Deng, Yan

    2013-06-01

    To investigate the migratory, metabolic and proliferative ability of rabbit fibrochondrocytes in meniscal fragments of different sizes under an in vivo subcutaneous environment. Adult, male, New Zealand white rabbit menisci were harvested and the inner two-thirds of each were minced into different sizes: 0.5 × 0.5 × 0.5 mm (group A); 1.0 × 1.0 × 1.0 mm (group B); 2.0 × 2.0 × 2.0 mm (group C). Meniscal fragments were packed into a fascia sheath, then implanted subcutaneously. At weeks 1, 2 and 3 postimplantation, meniscal fragments were harvested; cell migration and viability were then evaluated by confocal laser scanning microscopy and haematoxylin and eosin staining. Aggrecan was detected using Safranin O and Fast Green staining, and protein levels of types I and II collagen, and proliferating cell nuclear antigen (PCNA), were evaluated by immunohistochemistry. Protein levels of types I and II collagen and PCNA, and fibrochondrocyte migration, were highest in group A compared with groups B and C, but aggrecan staining remained the same across the groups. There was an inverse relationship between the migratory, metabolic and proliferative abilities of rabbit fibrochondrocytes and meniscal fragment size.

  10. Cartilage and meniscal T2 relaxation time as non-invasive biomarker for knee osteoarthritis and cartilage repair procedures

    PubMed Central

    Baum, T.; Joseph, G.B.; Karampinos, D.C.; Jungmann, P.M.; Link, T.M.; Bauer, J.S.

    2014-01-01

    SUMMARY Objective The purpose of this work was to review the current literature on cartilage and meniscal T2 relaxation time. Methods Electronic searches in PubMed were performed to identify relevant studies about T2 relaxation time measurements as non-invasive biomarker for knee osteoarthritis (OA) and cartilage repair procedures. Results Initial osteoarthritic changes include proteoglycan loss, deterioration of the collagen network, and increased water content within the articular cartilage and menisci. T2 relaxation time measurements are affected by these pathophysiological processes. It was demonstrated that cartilage and meniscal T2 relaxation time values were significantly increased in subjects with compared to those without radiographic OA and focal knee lesions, respectively. Subjects with OA risk factors such as overweight/obesity showed significantly greater cartilage T2 values than normal controls. Elevated cartilage and meniscal T2 relaxation times were found in subjects with vs without knee pain. Increased cartilage T2 at baseline predicted morphologic degeneration in the cartilage, meniscus, and bone marrow over 3 years. Furthermore, cartilage repair tissue could be non-invasively assessed by using T2 mapping. Reproducibility errors for T2 measurements were reported to be smaller than the T2 differences in healthy and diseased cartilage indicating that T2 relaxation time may be a reliable discriminatory biomarker. Conclusions Cartilage and meniscal T2 mapping may be suitable as non-invasive biomarker to diagnose early stages of knee OA and to monitor therapy of OA. PMID:23896316

  11. The effect of gluteus medius strengthening on the knee joint function score and pain in meniscal surgery patients

    PubMed Central

    Kim, Eun-Kyung

    2016-01-01

    [Purpose] The purpose of this study was to analyze the effect of gluteus medius activity strengthening due to squat with isometric hip adduction and hip abduction in side-lying exercise on knee joint function index and pain in meniscal surgery patients. [Subjects and Methods] This study selected sample of 26 patients who had meniscal surgery more than 4 weeks ago. The patients were divided into squat with isometric hip adduction exercise group I (n=8), hip abduction in side-lying exercise group II (n=9), and combined exercise group III. The lysholm score was used to evaluate knee joint function and visual analog scale was used to evaluate pain index of knee joint. [Results] Two-way repeated measures ANOVA was used to analyze the lysholm score and visual analog scale and showed significant interaction between the groups and durations. [Conclusion] Strengthening vastus medialis oblique and gluteus medius improved functional recovery and pain reduction of knee joint in meniscal injury surgery patients. Gluteus medius strengthening exercise is essential to meniscal injury surgery patients and should be included in rehabilitation program in early stages to be conducted systematically. PMID:27821928

  12. Epidemiology of Meniscal Injuries in U.S. High School Athletes from 2007/08 – 2012/13

    PubMed Central

    Mitchell, Joshua; Graham, William; Best, Thomas M.; Collins, Christy; Currie, Dustin W.; Comstock, R. Dawn; Flanigan, David C.

    2016-01-01

    Purpose Knowledge of epidemiologic trends of meniscal injuries in young active populations is limited. Better awareness of injury patterns is a first step to lowering injury rates. Our hypothesis was that meniscal injuries in high school athletes would vary by gender, sport, and type of exposure. Methods During 2007–2013, a large nationally disperse sample of US high schools reported athlete exposure and injury data for 22 sports by having certified athletic trainers complete an internet-based data collection tool. Results 1,082 meniscal injuries were reported during 21,088,365 athlete-exposures for an overall injury rate of 5.1 per 100,000 athlete exposures. The overall rate of injury was higher in competition (11.9) than practice (2.7) (RR = 4.4; 95% CI, 3.9–5.0), and 12/19 sports showed significantly higher injury rates in competition compared to practice. Of all injuries, 68.0% occurred in boys, yet among the gender-comparable sports of soccer, basketball, track and field, lacrosse, and baseball/softball injury rates were higher for girls than boys (5.5 and 2.5, respectively, RR = 2.2; 95% CI, 1.8–2.7). Contact injury represented the most common mechanism (55.9%). Surgery was performed for the majority of injuries (63.8%), and 54.0% of athletes had associated intra-articular knee pathology. Conclusions Meniscal injury patterns among high school athletes vary by gender, sport, and type of exposure. Overall rates are higher for boys, but this is driven by football; however in gender-comparable sports girls may be at higher risk for meniscal injury. Our study is clinically relevant because recognition of distinct differences in these injury patterns will help drive evidence-based, targeted injury prevention strategies and efforts. Level of Evidence Level III PMID:26506845

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

    PubMed

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

    2016-02-01

    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. 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. 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 10(5) 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 10(5) person-years in 1997 to 97 per 10(5) person-years in 2012, but not in Sweden. 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.

  14. 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. © 2015 Orthopaedic Research Society. Published by

  15. Medial perirhinal cortex disambiguates confusable objects.

    PubMed

    Kivisaari, Sasa L; Tyler, Lorraine K; Monsch, Andreas U; Taylor, Kirsten I

    2012-12-01

    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

  16. 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

  17. Medial septum regulates the hippocampal spatial representation.

    PubMed

    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.

  18. 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.

  19. International Meniscus Reconstruction Experts Forum (IMREF) 2015 Consensus Statement on the Practice of Meniscal Allograft Transplantation.

    PubMed

    Getgood, Alan; LaPrade, Robert F; Verdonk, Peter; Gersoff, Wayne; Cole, Brian; Spalding, Tim

    2016-08-25

    Meniscal allograft transplantation (MAT) has become relatively commonplace in specialized sport medicine practice for the treatment of patients with a symptomatic knee after the loss of a functional meniscus. The technique has evolved since the 1980s, and long-term results continue to improve. However, there still remains significant variation in how MAT is performed, and as such, there remains opportunity for outcome and graft survivorship to be optimized. The purpose of this article was to develop a consensus statement on the practice of MAT from key opinion leaders who are members of the International Meniscus Reconstruction Experts Forum so that a more standardized approach to the indications, surgical technique, and postoperative care could be outlined with the goal of ultimately improving patient outcomes.

  20. Meniscal repair by synovial flap transfer. Healing of the avascular zone in rabbits.

    PubMed

    Cisa, J; Basora, J; Madarnas, P; Ghibely, A; Navarro-Quilis, A

    1995-02-01

    We studied repair of a longitudinal incision of the right medial meniscus in 44 rabbits after the transfer of a pedunculated synovial flap, without immobilization of the knee. The left medial meniscus was used as the control, after creating the same lesion without synovial flap. Healing was analyzed by histologic studies, including India ink perfusion after 8, 12, 24, and 48 weeks. In three quarters of the cases, the meniscus showed healing with vascularization of an originally avascular zone.

  1. Posterior lateral meniscal root tear due to a malpositioned double-bundle anterior cruciate ligament reconstruction tibial tunnel.

    PubMed

    LaPrade, Christopher M; Jisa, Kyle A; Cram, Tyler R; LaPrade, Robert F

    2015-12-01

    The posterior lateral (PL) meniscal root plays an essential role in ensuring the health of the articular cartilage of the knee joint. Injuring the PL meniscal root has been demonstrated to result in significant deleterious changes to tibiofemoral contact mechanics. Anatomic studies have reported that the posterolateral bundle of the anterior cruciate ligament (ACL) and PL root lie in close proximity on the tibial plateau. Therefore, during a double-bundle ACL reconstruction, the PL root may be inadvertently injured during the reaming of the posterior ACL double-bundle reconstruction tibial tunnel that is intended to recreate the posterolateral bundle of the ACL. This case report describes an occurrence of iatrogenic injury to the PL root due to a posteriorly malpositioned double-bundle ACL tibial tunnel. This report is the first known description of this mechanism of injury in the literature. Case report, Level IV.

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

    PubMed

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

    2016-01-01

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

  3. Management of the Postbariatric Medial Thigh Deformity.

    PubMed

    Capella, Joseph F; Matarasso, Alan

    2016-05-01

    Thigh contour deformities-in particular, those of the medial thighs-are a common concern for many individuals seeking body contouring. Despite the frequency of this concern, some plastic surgeons have often been reluctant to embrace the medial thigh-lift procedure because of the risk for significant complications and relatively poor results. The authors' approach to medial thigh contouring is to address the variables outside of the medial thighs affecting the medial thighs before considering a medial thigh-lift procedure with a vertical component. In this article, the authors review the senior author's (J.F.C.) experience of 350 vertical medial thigh lifts in the weight-loss patient. The charts of 350 consecutive individuals who had undergone vertical medial thigh lifts were reviewed for complications and other variables. The procedures were all performed by the senior author between February of 2000 and February of 2014. The preoperative markings, current surgical technique, and postoperative care are described. There were 326 women and 24 men in the study, with an average age of 43 years. The overall complication rate was 45.14 percent. Skin dehiscence and seroma formation were the most frequent complications, at 31.14 percent and 18.18 percent, respectively. The vast majority of patients were pleased with the aesthetic and functional results of their surgery. The medial thigh deformities of the weight-loss patient are effectively addressed by a vertical medial thigh lift when the variables adjacent to the medial thighs are first treated by a body lift. Therapeutic, IV.

  4. Repair of Torn Avascular Meniscal Cartilage Using Undifferentiated Autologous Mesenchymal Stem Cells: From In Vitro Optimization to a First‐in‐Human Study

    PubMed Central

    Whitehouse, Michael R.; Howells, Nicholas R.; Parry, Michael C.; Austin, Eric; Kafienah, Wael; Brady, Kyla; Goodship, Allen E.; Eldridge, Jonathan D.; Blom, Ashley W.

    2016-01-01

    Abstract Meniscal cartilage tears are common and predispose to osteoarthritis (OA). Most occur in the avascular portion of the meniscus where current repair techniques usually fail. We described previously the use of undifferentiated autologous mesenchymal stem cells (MSCs) seeded onto a collagen scaffold (MSC/collagen‐scaffold) to integrate meniscal tissues in vitro. Our objective was to translate this method into a cell therapy for patients with torn meniscus, with the long‐term goal of delaying or preventing the onset of OA. After in vitro optimization, we tested an ovine‐MSC/collagen‐scaffold in a sheep meniscal cartilage tear model with promising results after 13 weeks, although repair was not sustained over 6 months. We then conducted a single center, prospective, open‐label first‐in‐human safety study of patients with an avascular meniscal tear. Autologous MSCs were isolated from an iliac crest bone marrow biopsy, expanded and seeded into the collagen scaffold. The resulting human‐MSC/collagen‐scaffold implant was placed into the meniscal tear prior to repair with vertical mattress sutures and the patients were followed for 2 years. Five patients were treated and there was significant clinical improvement on repeated measures analysis. Three were asymptomatic at 24 months with no magnetic resonance imaging evidence of recurrent tear and clinical improvement in knee function scores. Two required subsequent meniscectomy due to retear or nonhealing of the meniscal tear at approximately 15 months after implantation. No other adverse events occurred. We conclude that undifferentiated MSCs could provide a safe way to augment avascular meniscal repair in some patients. Registration: EU Clinical Trials Register, 2010‐024162‐22. Stem Cells Translational Medicine 2017;6:1237–1248 PMID:28186682

  5. Spontaneous osteonecrosis of the knee involving both the medial femoral condyle and the medial tibial plateau: report of three cases.

    PubMed

    Jung, Kwang Am; Lee, Su Chan; Hwang, Seung Hyun; Kim, Duk Su; Kim, Taek Keun

    2008-08-01

    Spontaneous osteonecrosis of the knee (SPONK) usually involves a single condyle or plateau. The medial femoral condyle (MFC) is most often involved and spontaneous osteonecrosis of the medial tibial plateau (MTP) is a rare condition, representing only 2% of all necroses reported in the knee. SPONK involving both the MFC and the MTP is extremely rare. SPONK occurring in either the MFC or the MTP individually might extend to the corresponding side of the knee in the advanced end-stage; however, in that situation, significant degenerative changes would exist and it might be difficult to differentiate end-stage SPONK form severe osteoarthritis. SPONK affecting both the MFC and the MTP without significant secondary osteoarthritic changes has not been reported, even though it is difficult to know which occurs first. We have cared for three patients with histologically proven osteonecrosis of the MFC and MTP and report their radiologic features.

  6. Dynamic and static knee alignment at baseline predict structural abnormalities on MRI associated with medial compartment knee osteoarthritis after 2 years.

    PubMed

    Mahmoudian, Armaghan; van Dieёn, Jaap H; Bruijn, Sjoerd M; Baert, Isabel A C; Faber, Gert S; Luyten, Frank P; Verschueren, Sabine M P

    2017-09-01

    Dynamic and static varus alignment, both, have been reported as risk factors associated with structural progression of knee osteoarthritis. However the association of none of the static and dynamic alignment with structural, clinical, and functional progression associated with knee osteoarthritis has not been assessed yet in a longitudinal study. Forty-seven women with early and established medial knee osteoarthritis were evaluated. Static and dynamic alignment as well as MRI detected structural features, clinical, and functional characteristics of patients were assessed at baseline and at 2 years follow-up. Associations between baseline static and dynamic alignment with structural, functional, and clinical characteristics at the time of entry, as well as the changes over 2 years were evaluated. Both static and dynamic varus alignment at baseline were significantly associated with osteoarthritis related tibio-femoral joint structural abnormalities detected on MRI, at the time of entry. Only the magnitude of varus thrust at baseline was predictive of the changes in the presence of meniscal maceration over two years. None of the static or dynamic measures of knee joint alignment were associated with clinical characteristics associated with medial knee osteoarthritis. The key finding of this study is that both frontal plane dynamic and static alignment, are associated with structural abnormalities in patients with medial knee osteoarthritis. Copyright © 2017. Published by Elsevier B.V.

  7. 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

  8. Magnetic resonance imaging lesions are more severe and cartilage T2 relaxation time measurements are higher in isolated lateral compartment radiographic knee osteoarthritis than in isolated medial compartment disease - data from the Osteoarthritis Initiative.

    PubMed

    Wise, B L; Niu, J; Guermazi, A; Liu, F; Heilmeier, U; Ku, E; Lynch, J A; Zhang, Y; Felson, D T; Kwoh, C K; Lane, N E

    2017-01-01

    Isolated lateral compartment tibiofemoral radiographic osteoarthritis (IL-ROA) is an understudied form of knee osteoarthritis (OA). The objective of the present study was to characterize Magnetic Resonance Imaging (MRI) abnormalities and MR-T2 relaxation time measurements associated with IL-ROA and with isolated medial compartment ROA (IM-ROA) compared with knees without OA. 200 case subjects with IL-ROA (Kellgren/Lawrence (K/L) grade≥2 and joint space narrowing (JSN) > 0 in the lateral compartment but JSN = 0 in the medial compartment) were randomly selected from the Osteoarthritis Initiative baseline visit. 200 cases with IM-ROA and 200 controls were frequency matched to the IL-ROA cases. Cases and controls were analyzed for odds of having a subregion with >10% cartilage area affected, with ≥25% bone marrow lesions (BML), with meniscal tear or maceration, and for association with cartilage T2 values. IL-ROA was more strongly associated with ipsilateral MRI knee pathologies than IM-ROA (IL-ROA: OR = 135.2 for size of cartilage lesion, 95% CI 42.7-427.4; OR = 145.4 for large size BML, 95% CI 41.5-509.5; OR = 176 for meniscal tears, 95% CI 59.8-517.7; IM-ROA: OR = 28.4 for size of cartilage lesion, 95% CI 14.7-54.7; OR = 38.1 for size of BML, 95% CI 12.7-114; OR = 37.0 for meniscal tears, 95% CI 12-113.6). Cartilage T2 values were higher in both tibial and medial femoral compartments in IL-ROA, but in IM-ROA were only significantly different from controls in the medial femur. IL-ROA knees show a greater prevalence and severity of MRI lesions and higher cartilage T2 values than IM-ROA knees compared with controls. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  9. 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

  10. Effectiveness of electrical stimulation on rehabilitation after ligament and meniscal injuries: a systematic review.

    PubMed

    Imoto, Aline Mizusaki; Peccin, Stella; Almeida, Gustavo Jerônimo Melo; Saconato, Humberto; Atallah, Álvaro Nagib

    2011-12-01

    Electrical stimulation (ES) is widely used to strengthen muscles following ligament and meniscal injuries. The aim of this study was to evaluate the effectiveness of ES for rehabilitation after soft tissue injuries of the knee treated surgically or conservatively. Systematic review at the Brazilian Cochrane Center. We searched the Cochrane Central Register of Controlled Trials (2010, Issue 12), Medline (Medical Analysis and Retrieval System Online) via PubMed (1966 to December 2010), Embase (Excerpta Medica database, 1980 to December 2010), Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde, 1982 to December 2010), and PEDro (Physiotherapy Evidence Database, 1929 to December 2010). The studies included were randomized controlled trials using ES to increase muscle strength for rehabilitation of patients with soft tissue injuries of the knee. Two authors independently evaluated studies for inclusion and performed data extraction and methodological quality assessment. Seventeen studies evaluating ES after anterior cruciate ligament reconstruction and two studies evaluating ES after meniscectomy were included. There was a statistically significant improvement in quadriceps strength through ES (mean difference, MD: -32.7; 95% confidence interval, CI: -39.92 to -25.48; n = 56) and in functional outcomes (MD -7; -12.78 to -1.22; n = 43) six to eight weeks after surgical reconstruction of the anterior cruciate ligament. There is evidence that ES coupled with conventional rehabilitation exercises may be effective in improving muscle strength and function two months after surgery.

  11. The snapping medial antebrachial cutaneous nerve.

    PubMed

    Cesmebasi, Alper; O'driscoll, Shawn W; Smith, Jay; Skinner, John A; Spinner, Robert J

    2015-10-01

    Snapping elbow is a well-known condition where elbow flexion and extension elicits a painful, popping sensation. The most frequent etiology is anterior dislocation of the ulnar nerve over the medial epicondyle. Four patients (3 females and 1 male) presented with complaints of a popping sensation in the elbow, pain over the medial aspect of the forearm, and ulnar neuritis. All patients underwent preoperative dynamic ultrasound and surgical exploration of the medial elbow. Intraoperatively, snapping of the MABC over the medial epicondyle was discovered in all four patients. In three patients, there was abnormal displacement of the medial triceps and ulnar nerve: in two of these, both structures dislocated over the medial epicondyle and in one patient both structures subluxated. In each case, the MABC was decompressed (n = 1) and transposed (n = 3), and in three cases, the medial triceps and ulnar nerve were addressed as well. Symptomatic improvement was achieved in all cases. Retrospective review of the ultrasound revealed the snapping MABC, though it was less effective prospectively in the cases when snapping MABC was not suspected. In conclusion, snapping of the MABC broadens the spectrum of disorders that results in snapping elbow. To our knowledge, we are unaware of prior reports of this entity.

  12. Molecular analysis of age and sex-related gene expression in meniscal tears with and without a concomitant anterior cruciate ligament tear.

    PubMed

    Brophy, Robert H; Rai, Muhammad Farooq; Zhang, Zhiqi; Torgomyan, Adelina; Sandell, Linda J

    2012-03-07

    The meniscus plays critical roles in the knee, contributing to load transmission, shock absorption, and joint stability. Little is known about gene expression in meniscal tears, particularly in relation to injury pattern and patient age and sex. The purpose of this study was to test the hypothesis that gene expression in meniscal tears varies depending on patient age and sex and whether the anterior cruciate ligament (ACL) is also torn. Meniscal tissue from twenty-eight patients with an isolated meniscal tear or a meniscal tear with a concomitant ACL tear was collected at the time of clinically indicated partial meniscectomy. Messenger RNA (mRNA) expression was examined by quantitative real-time polymerase chain reaction for molecular markers of osteoarthritis including proinflammatory cytokines (interleukin [IL]-1α, IL-1β, IL-6, and tumor necrosis factor-alpha [TNFα]), chemokines (IL-8, CCL3, CCL3L1, CXCL1, CXCL3, CXCL6, and CCL20), aggrecanases (ADAMTS-4 [a disintegrin and metalloproteinase with thrombospondin type-4 motifs] and ADAMTS-5), matrix metalloproteinases (MMP-1, MMP-3, MMP-9, and MMP-13), transcription factors (NFκB2 [nuclear factor kappa B2], NFκBIA [NF-kappa B inhibitor alpha], and IκBA [inhibitor of kappa B alpha]), and matrix components (bone morphogenetic protein [BMP]-2, type-I collagen alpha 1 [Col1a1], Col2a1, and aggrecan). Expression of IL-1β (p = 0.02), ADAMTS-5 (p = 0.001), MMP-1 (p = 0.007), MMP-9 (p = 0.002), MMP-13 (p = 0.01), and NFκB2 (p = 0.01) was significantly higher in patients with a meniscal tear who were under the age of forty years than it was in those over the age of forty years. Similarly, the expression of ADAMTS-4 (p = 0.002), ADAMTS-5 (p = 0.02), MMP-1 (p = 0.02), and MMP-13 (p = 0.0002) was higher in patients with a meniscal tear and an ACL tear who were under the age of forty years than it was in those over forty years. In patients with a meniscal tear and an ACL tear, the expression of IL-1β (p = 0.01), TNF

  13. 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

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

    PubMed

    Fournier, Pierre-Etienne

    2003-06-01

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

  15. 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

  16. A Contact Pressure Analysis Comparing an All-Inside and Inside-Out Surgical Repair Technique for Bucket-Handle Medial Meniscus Tears.

    PubMed

    Marchetti, Daniel Cole; Phelps, Brian M; Dahl, Kimi D; Slette, Erik L; Mikula, Jacob D; Dornan, Grant J; Bucci, Gabriella; Turnbull, Travis Lee; Singleton, Steven B

    2017-10-01

    To directly compare effectiveness of the inside-out and all-inside medial meniscal repair techniques in restoring native contact area and contact pressure across the medial tibial plateau at multiple knee flexion angles. Twelve male, nonpaired (n = 12), fresh-frozen human cadaveric knees underwent a series of 5 consecutive states: (1) intact medial meniscus, (2) MCL tear and repair, (3) simulated bucket-handle longitudinal tear of the medial meniscus, (4) inside-out meniscal repair, and (5) all-inside meniscal repair. Knees were loaded with a 1,000-N axial compressive force at 5 knee flexion angles (0°, 30°, 45°, 60°, 90°), and contact area, mean contact pressure, and peak contact pressure were calculated using thin film pressure sensors. No significant differences were observed between the inside-out and all-inside repair techniques at any flexion angle for contact area, mean contact pressure, and peak contact pressure (all P > .791). Compared with the torn meniscus state, inside-out and all-inside repair techniques resulted in increased contact area at all flexion angles (all P < .005 and all P < .037, respectively), decreased mean contact pressure at all flexion angles (all P < .007 and all P < .001, respectively) except for 0° (P = .097 and P = .39, respectively), and decreased peak contact pressure at all flexion angles (all P < .001, all P < .001, respectively) except for 0° (P = .080 and P = .544, respectively). However, there were significant differences in contact area and peak contact pressure between the intact state and inside-out technique at angles ≥45° (all P < .014 and all P < .032, respectively). Additionally, there were significant differences between the intact state and all-inside technique in contact area at 60° and 90° and peak contact pressure at 90° (both P < .005 and P = .004, respectively). Median values of intact contact area, mean contact pressure, and peak contact pressure over the tested flexion angles ranged

  17. Medial medullary infarction: abnormal ocular motor findings.

    PubMed

    Kim, J Soo; Choi, K-D; Oh, S-Y; Park, S-H; Han, M-K; Yoon, B-W; Roh, J-K

    2005-10-25

    In 20 consecutive patients with isolated medial medullary infarction, abnormal ocular motor findings included nystagmus (n = 8), ocular contrapulsion (n = 5), and contralesional ocular tilt reaction (n = 2). The nystagmus was ipsilesional (n = 4), gaze-evoked (n = 5), upbeating (n = 4), and hemiseesaw (n = 1). The ocular motor abnormalities may be explained by involvements of the nucleus prepositus hypoglossi, medial longitudinal fasciculus or efferent fibers from the vestibular nuclei, climbing fibers, and cells of the paramedian tracts.

  18. Good results five years after surgical management of anterior cruciate ligament tears, and meniscal and cartilage injuries.

    PubMed

    Osti, Leonardo; Papalia, Rocco; Del Buono, Angelo; Amato, Cirino; Denaro, Vincenzo; Maffulli, Nicola

    2010-10-01

    In athletes with anterior cruciate ligament (ACL) tears combined with meniscal and cartilage injuries, the goals are to restore knee laxity and relieve symptoms, while long-term goals are the return to pre-injury sport activity and to prevent onset of degenerative changes. We compared the post-operative (minimum 5 years) clinical and radiological outcomes of 50 patients, similar for ACL rupture and meniscal tears, but different for the grade of cartilage lesion. The patient population was divided into two groups similar for ACL reconstruction and surgical meniscal management. Group 1 included 25 patients undergoing microfracture management of grade III-IV cartilage lesions, while Group 2 included 25 patients with grade I-II cartilage lesions, managed by radiofrequency. Comparing pre- and post-operative status, Lachman test, pivot shift values and KT 1000 side to side difference measurements improved significantly (<.001) in both groups, with NS difference between the two groups (>0.05) at the intermediate and latest assessments. At both post-operative appointments, in both groups, the average Lysholm score and IKDC ranking rates improved significantly (<0.001) compared to pre-operative values, but slight worsening was observed in Group 1 patients at the latest review. At the latest assessment, 10 knees (40%) in Group 1 and 3 knees (15%) in Group 2 demonstrated degenerative changes according to Fairbank grading. Concerning the WOMAC index score and sport activity level rating, Group 1 patients had significantly lower scores than Group 2 patients (P < 0.05). In patients with symptomatic ACL instability combined to grade III-IV cartilage lesions, microfractures give excellent short-term clinical and functional improvement but do not prevent the evolution of degenerative changes.

  19. Meniscal tears: comparison of the conventional spin-echo and fast spin-echo techniques through image processing

    PubMed Central

    2014-01-01

    Background Conventional spin-echo (PD-CSE) and fast spin-echo (PD-FSE) techniques are frequently used to detect meniscal tears. However, the time delay for imaging with PD-CSE has resulted in its replacement with faster techniques, such as proton density fast spin-echo (PD-FSE), which has become a frequent tool at most diagnostic centres. Qualitative analysis shows that the PD-CSE technique is more sensitive, but other authors have not found significant differences between the aforementioned techniques. Therefore, we performed a quantitative analysis in this study that aims to measure differences in the quality of the images obtained with both techniques. Methods We compared the PD-CSE and PD-FSE techniques by quantitatively analysing the obtained proton density images: the area shown, as well as the brightness and lesion contrast of the obtained image. A set of 100 images from 50 patients thought to contain meniscal tears of the knee were selected. These 100 images were obtained from all individuals using both the PD-CSE and PD-FSE techniques. The images were processed using software developed in Delphi. In addition to these quantifications, three physicians, who are specialists in radiology and capable of analysing magnetic resonance (MR) images of the musculoskeletal system, qualitatively analysed the diagnostic sensitivity of both techniques. Results On average, samples obtained via the PD-CSE technique contained 22% more pixels in the lesion area. The contrast differed by 28%, and the brightness differed by 31%. The two techniques were correlated using Student’s t-test, which showed a statistically significant difference. The specialists detected meniscal tears in 30 of the images obtained via the PD-CSE technique, while only 72% of these cases were detected via the PD-FSE technique. Conclusions The PD-CSE technique was shown to be superior to PD-FSE for all of the evaluated properties, making its selection preferable. PMID:24673813

  20. Anconeus epitrochlearis as a source of medial elbow pain in baseball pitchers.

    PubMed

    Li, Xinning; Dines, Joshua S; Gorman, Matthew; Limpisvasti, Orr; Gambardella, Ralph; Yocum, Lou

    2012-07-01

    Medial elbow pain is reported in 18% to 69% of baseball players aged of 9 and 19 years. This is due to the large valgus stresses focused on the medial side of the elbow during overhead activities. In overhead throwers and pitchers, pain can be attributed to valgus extension overload with resultant posteromedial impingement, overuse of the flexor-pronator musculature resulting in medial epicondylitis, or occasional muscle tears or ruptures. The anconeus epitrochlearis is a known cause of cubital tunnel syndrome and has been postulated as a source of medial elbow pain in overhead athletes. This article describes the cases of 3 right-handed baseball pitchers with persistent right-sided medial elbow pain during throwing despite a prolonged period of rest, physical therapy, and nonsteroidal anti-inflammatory drugs. Two patients had symptoms of cubital tunnel syndrome as diagnosed by electromyogram and nerve conduction studies and the presence of the anconeus epitrochlearis muscle per magnetic resonance imaging. All patients underwent isolated release of the anconeus muscle without ulnar nerve transposition and returned to their previous levels of activity. The diagnosis and treatment of pitchers who present with medial-sided elbow pain can be complex. The differential should include an enlarged or inflamed anconeus epitrochlearis muscle as a possible cause. Conservative management should be the first modality. However, surgical excision with isolated release of the muscle can be successful in returning patients with persistent pain despite a trial of conservative management to their previous levels of function.

  1. Regional divergence of palate medial edge epithelium along the anterior to posterior axis.

    PubMed

    Jin, Jiu-Zhen; Warner, Dennis R; Ding, Jixiang

    2014-01-01

    Recent studies have shown that mouse palatal mesenchymal cells undergo regional specification along the anterior-posterior (A-P) axis defined by anterior Shox2 and Msx1 expression and posterior Meox2 expression. A-P regional specification of the medial edge epithelium, which is directly responsible for palate fusion, has long been proposed, but it has not yet been demonstrated due to the lack of regional specific markers. In this study, we have demonstrated that the palate medial edge epithelium is regionalized along the A-P axis, similar to that for the underlying mesenchyme. Mmp13, a medial edge epithelium specific marker, was uniformly expressed from anterior to posterior in wild-type mouse palatal shelves. Previous studies demonstrated that medial edge epithelium expression of Mmp13 was regulated by TGF-beta3. We have found that the changes in Mmp13 expression in TGF-beta3 knockouts varied along the A-P axis, and can be broken down into three distinct regions. These regions correlated with regional specification of the underlying medial edge mesenchymal cells and timing of palate fusion. Mouse palate medial edge epithelium along the A-P axis can be divided into different regions according to the differential response to the loss of TGF-beta3.

  2. The medial sural artery perforator free flap.

    PubMed

    Cavadas, P C; Sanz-Giménez-Rico, J R; Gutierrez-de la Cámara, A; Navarro-Monzonís, A; Soler-Nomdedeu, S; Martínez-Soriano, F

    2001-11-01

    The medial sural artery supplies the medial gastrocnemius muscle and sends perforating branches to the skin. The possible use of these musculocutaneous perforators as the source of a perforator-based free flap was investigated in cadavers. Ten legs were dissected, and the topography of significant perforating musculocutaneous vessels on both the medial and the lateral gastrocnemius muscles was recorded. A mean of 2.2 perforators (range, 1 to 4) was noted over the medial gastrocnemius muscle, whereas in only 20 percent of the specimens was a perforator of moderate size noted over the lateral gastrocnemius muscle. The perforating vessels from the medial sural artery clustered about 9 to 18 cm from the popliteal crease. When two perforators were present (the most frequent case), the perforators were located at a mean of 11.8 cm (range, 8.5 to 15 cm) and 17 cm (range, 15 to 19 cm) from the popliteal crease. A series of six successful clinical cases is reported, including five free flaps and one pedicled flap for ipsilateral lower-leg and foot reconstruction. The dissection is somewhat tedious, but the vascular pedicle can be considerably long and of suitable caliber. Donor-site morbidity was minimal because the muscle was not included in the flap. Although the present series is short, it seems that the medial sural artery perforator flap can be a useful flap for free and pedicled transfer in lower-limb reconstruction.

  3. 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

  4. Importance of independent measurement of width and length of lateral meniscus during preoperative sizing for meniscal allograft transplantation.

    PubMed

    Yoon, Jung-Ro; Kim, Taik-Sun; Wang, Joon-Ho; Yun, Ho-Hyun; Lim, Hyungtae; Yang, Jae-Hyuk

    2011-07-01

    Successful meniscus transplantation depends on an accurate sizing of the meniscal allograft. Although accurate sizing of the meniscal allograft is crucial during meniscus transplantation, the accuracy of meniscal measurement methods is still in debate. This study was undertaken to evaluate the relationship between the width and length of the lateral meniscus. These anatomic dimensions were also evaluated in the context of the patient's height, weight, gender, and body mass index (BMI). Descriptive laboratory study. Ninety-one samples of fresh lateral meniscus were obtained during total knee arthroplasty. The samples were obtained carefully without injuring the meniscus itself and the bony attachment sites. For each lateral meniscus, the anatomic dimensions (width [LMW] and length [LML]) were recorded. The height, weight, gender, and BMI of the patients were also recorded. The Pearson correlation and multivariate and linear regression analysis were applied for each variable. The accuracy was defined as those measures that fell within 10% of the original size. A P value ≤ .05 was considered significant. The mean LMW was 30.7 mm (standard deviation [SD] = 3.5) and 27.0 mm (SD = 2.6) for men and women, respectively. The mean LML was 33.7 mm (SD = 4.3) and 30.8 mm (SD = 2.6) for men and women, respectively. Thirty-nine samples (42.5%) showed LMW measurements within a 10% difference of LML, whereas 50 samples (55%) showed an LMW greater than a 10% difference of LML. Although there were correlations between LML with LMW in men and correlations between weight and LMW with LML in women, the accuracy for the derived linear regression formulas was 3%, 9%, and 12%, respectively. The length cannot be predicted accurately from the width of the lateral meniscus. The height, weight, gender, and BMI failed to estimate the dimensions of the lateral meniscus. Therefore, it is essential to measure the width and length separately and match it with the allograft with other size

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

    PubMed Central

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

    2017-01-01

    Background Intracranial internal carotid artery (iICA) calcification is associated with stroke and is often seen as a proxy of atherosclerosis of the intima. However, it was recently shown that these calcifications are predominantly located in the tunica media and internal elastic lamina (medial calcification). Intimal and medial calcifications are thought to have a different pathogenesis and clinical consequences and can only be distinguished through ex vivo histological analysis. Therefore, our aim was to develop CT scoring method to distinguish intimal and medial iICA calcification in vivo. Methods First, in both iICAs of 16 cerebral autopsy patients the intimal and/or medial calcification area was histologically assessed (142 slides). Brain CT images of these patients were matched to the corresponding histological slides to develop a CT score that determines intimal or medial calcification dominance. Second, performance of the CT score was assessed in these 16 patients. Third, reproducibility was tested in a separate cohort. Results First, CT features of the score were circularity (absent, dot(s), <90°, 90–270° or 270–360°), thickness (absent, ≥1.5mm, or <1.5mm), and morphology (indistinguishable, irregular/patchy or continuous). A high sum of features represented medial and a lower sum intimal calcifications. Second, in the 16 patients the concordance between the CT score and the dominant calcification type was reasonable. Third, the score showed good reproducibility (kappa: 0.72 proportion of agreement: 0.82) between the categories intimal, medial or absent/indistinguishable. Conclusions The developed CT score shows good reproducibility and can differentiate reasonably well between intimal and medial calcification dominance in the iICA, allowing for further (epidemiological) studies on iICA calcification. PMID:28060941

  6. Incidence of depression of the medial orbital wall without a recent trauma event.

    PubMed

    Hwang, Kun; Kim, Han Joon; Park, Joo Won; Lee, Seong Sim; Kim, Hyeon Jeong; Tae, Na Yeong

    2014-09-01

    The aim of this study was to see how frequently depression of the orbital medial wall can be found on computed tomographic (CT) imaging of patients without a recent trauma event. A total of 14,628 CT scans (12,515 brain CT scans and 2113 three-dimensional facial CT scans) of patients with no recent trauma event (defined as a facial trauma within 1 mo) were reviewed. If there was a depression of more than 3 mm on the medial wall compared with the contralateral side in the axial view, the scan was included in the "depression or asymmetry" group. In the depression or asymmetry group, old fractures and recent fractures were differentiated according to the degree of swelling of the medial rectus muscle and soft tissue swelling. Among the 14,628 CT scans with no recent facial trauma event, 836 cases (5.7%) had depression or an asymmetric medial wall. Most (94.3%, 788 cases) of the 836 cases were discovered to have an old medial wall fracture, whereas 39 cases (4.7%) were reported to have a recent medial wall fracture despite not having a recent facial trauma event. Only 9 cases (1.1%) were revealed to have a mucocele. It is noteworthy that 5.3% (788 cases among the 14,628 cases) had an old medial wall fracture despite not having any facial trauma within 1 month. The reason for this relatively high ratio is thought to be because medial fractures are often undetected with conventional plain x-ray imaging.

  7. Trends in Meniscal Allograft Transplantation in the United States, 2007 to 2011.

    PubMed

    Cvetanovich, Gregory L; Yanke, Adam B; McCormick, Frank; Bach, Bernard R; Cole, Brian J

    2015-06-01

    The purpose of this study was to investigate the incidence of meniscal allograft transplantation (MAT) in the United States from 2007 to 2011 and to analyze trends in MAT using a large database of privately insured non-Medicare patients. Patients who underwent MAT (Current Procedural Terminology [CPT] code 29868) from 2007 to 2011 were identified using the PearlDiver Private Payer Database. Demographic and use data available in the database were extracted for patients who underwent MAT. Statistical analysis involved Student t tests, χ-square tests, and linear regression analyses, with statistical significance set at P < .05. The PearlDiver database allowed analysis of approximately 25.4 million patients per year during the years 2007 to 2011 (approximately 9% of the US population younger than 65 years). From 2007 to 2011, there were a total of 302 MAT procedures, for an incidence of 0.24 MAT procedures per year per 100,000 patients. There was no statistically significant increase in MAT procedures over time (P = .36). There was a higher incidence of MAT in male patients (0.26) than in female patients (0.19) (P = .001). There was a higher incidence of MAT in patients aged 25 to 34 years (0.40) and in those younger than 25 years (0.30) compared with older patients (P < .001), with 9.7% of MAT procedures being performed in patients younger than age 35 years. MAT was an uncommon procedure, with no change in its incidence from 2007 to 2011. MAT procedures were performed more commonly in patients younger than 35 years and in male patients. Level IV, descriptive epidemiology study. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  8. Finite Element Analysis of Meniscal Anatomical 3D Scaffolds: Implications for Tissue Engineering

    PubMed Central

    Moroni, L; Lambers, F.M; Wilson, W; van Donkelaar, C.C; de Wijn, JR; Huiskesb, R; van Blitterswijk, C.A

    2007-01-01

    Solid Free-Form Fabrication (SFF) technologies allow the fabrication of anatomical 3D scaffolds from computer tomography (CT) or magnetic resonance imaging (MRI) patients’ dataset. These structures can be designed and fabricated with a variable, interconnected and accessible porous network, resulting in modulable mechanical properties, permeability, and architecture that can be tailored to mimic a specific tissue to replace or regenerate. In this study, we evaluated whether anatomical meniscal 3D scaffolds with matching mechanical properties and architecture are beneficial for meniscus replacement as compared to meniscectomy. After acquiring CT and MRI of porcine menisci, 3D fiber-deposited (3DF) scaffolds were fabricated with different architectures by varying the deposition pattern of the fibers comprising the final structure. The mechanical behaviour of 3DF scaffolds with different architectures and of porcine menisci was measured by static and dynamic mechanical analysis and the effect of these tissue engineering templates on articular cartilage was assessed by finite element analysis (FEA) and compared to healthy conditions or to meniscectomy. Results show that 3DF anatomical menisci scaffolds can be fabricated with pore different architectures and with mechanical properties matching those of natural menisci. FEA predicted a beneficial effect of meniscus replacement with 3D scaffolds in different mechanical loading conditions as compared to meniscectomy. No influence of the internal scaffold architecture was found on articular cartilage damage. Although FEA predictions should be further confirmed by in vitro and in vivo experiments, this study highlights meniscus replacement by SFF anatomical scaffolds as a potential alternative to meniscectomy. PMID:19662124

  9. 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…

  10. 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,…

  11. 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,…

  12. Biomechanical testing of suture-based meniscal repair devices containing ultrahigh-molecular-weight polyethylene suture: update 2011.

    PubMed

    Barber, F Alan; Herbert, Morley A; Bava, Eric D; Drew, Otis R

    2012-06-01

    To evaluate the biomechanical characteristics of recently introduced ultrahigh-molecular-weight polyethylene suture-based, self-adjusting meniscal repair devices. Updating a prior study published in 2009, we made vertical longitudinal cuts 3 mm from the periphery in fresh-frozen adult human menisci to simulate a bucket-handle meniscus tear. Each tear was then repaired by a single repair technique in 10 meniscus specimens. Group 1 menisci were repaired with a vertical mattress suture of No. 2-0 Ethibond (Ethicon, Somerville, NJ). Group 2 menisci were repaired with a vertical mattress suture of No. 2-0 OrthoCord (DePuy Mitek, Raynham, MA). Group 3 menisci were repaired with a single OmniSpan device with No. 2-0 OrthoCord suture (DePuy Mitek). Group 4 menisci were repaired with a single Meniscal Cinch device with No. 2-0 FiberWire suture (Arthrex, Naples, FL). Group 5 menisci were repaired with a single MaxFire device inserted with the MarXmen gun (Biomet Sports Medicine, Warsaw, IN). Group 6 menisci were repaired with a Sequent device with No. 0 Hi-Fi suture (ConMed Linvatec, Largo, FL) in a "V" suture configuration. Group 7 menisci were repaired with a single FasT-Fix 360 device (Smith & Nephew Endoscopy, Andover, MA). By use of a mechanical testing machine, all samples were preloaded at 5 N and cycled 200 times between 5 and 50 N. Those specimens that survived were destructively tested at 5 mm/min. Endpoints included maximum load, displacement, stiffness, and failure mode. Mean failure loads were as follows: Ethibond suture, 73 N; OrthoCord suture, 88 N; OmniSpan, 88 N; Cinch, 71 N; MarXmen/MaxFire, 54 N; Sequent, 66 N; and FasT-Fix 360, 60 N. Ethibond was stronger than MarXmen/MaxFire. The mean displacement after 100 cycles was as follows: Ethibond, 2.58 mm; OrthoCord, 2.75 mm; OmniSpan, 2.51 mm; Cinch, 2.65 mm; MarXmen/MaxFire, 3.67 mm; Sequent, 3.35 mm; and FasT-Fix 360, 1.13 mm. The MarXmen/MaxFire showed greater 100-cycle displacement than Ethibond and Fas

  13. Medial Unicompartmental Knee Arthroplasty in Patients with Spontaneous Osteonecrosis of the Knee

    PubMed Central

    Choy, Won-Sik; Lee, Sang Ki; Yang, Dae Suk; Kim, Choon Myeon; Park, Ju Sang

    2011-01-01

    Background We analyzed the clinical and radiologic results of patients with spontaneous osteonecrosis of the knee treated by minimally invasive medial unicompartmental arthroplasty using Oxford Uni. Methods We reviewed 22 knees in 21 patients which were treated for spontaneous osteonecrosis between 2002 and 2006. Patients included one male and 20 females. The mean age was 70.8 years (range, 53 to 82 years). The mean follow-up period was 70.3 months (range, 48 to 93 months). The clinical results were evaluated using the Hospital for Special Surgery (HSS) knee score and the range of motion of the knee preoperatively and at the final follow-up. Preoperative plain radiographs and magnetic resonance images were analyzed to determine the size and stage of osteonecrotic lesions. Results The mean HSS knee score was 64.3 (range, 54 to 75) preoperatively and 92.0 (range, 71 to 100) at the final follow-up. The mean preoperative flexion contracture was 8.9° (range, 0 to 15°) and 0.2° (range, 0 to 5°) at the final follow-up. The mean further flexion increased from 138.6° (range, 100 to 145°) preoperatively to 145.6° (range, 140 to 150°) at the final follow-up. Active full flexion was possible within 2 months of the operation. The squatting position was possible in 16 patients (84.2%) out of 19, except one case of bronchiectasis and one case of spine fracture. The cross-leg posture was possible in 19 patients (90.5%) out of 21. The mean tibiofemoral angle was improved from varus 0.98° to valgus 3.22°. Meniscal bearing dislocation occurred in 2 cases and femoral component loosening occurred in 1 case. Conclusions Unicompartmental knee arthroplasty using Oxford Uni could be an alternative treatment option in spontaneous osteonecrosis of the knee. PMID:22162790

  14. 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. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. Arthroscopic patterns of the poster-medial aspect of the knee joint: classification of the gastrocnemius-semimembranosus gateway and its relationship with Baker’s cyst

    PubMed Central

    Calvisi, Vittorio; Zoccali, Carmine

    2016-01-01

    Summary Background The gastrocnemius-semimembranosus bursa may communicate with the knee joint. The arthroscopic anatomy of the posteromedial aspect varies depending on the angle of the oblique popliteal ligament, the level at which it crosses the medial gastrocnemius tendon, and its relationship with the capsular joint and synovia. The aim of this paper is to identify possible patterns, and to evaluate their characteristics and their relationship with Baker’s cyst. Methods data archived from 185 consecutive arthroscopies were evaluated; an anatomic description and classification was carried out; the percentages of association with BC and the associated pathologies were reported. Results The different anatomies were classified into six groups based on the relationship above the medial gastrocnemius tendon, the capsular joint and synovia. The prevalence of Baker’s cyst was 28.3%. The main associated intra-articular pathological condition was the contemporary presence of a meniscal tear and chondropathy. Conclusion Exploration of the posterior aspect of the knee must be performed routinely. Knowing the possible anatomy patterns of the posteromedial arthroscopic aspect of the knee joint could help to identify the cyst and its gateway, thus facilitating its treatment. Level of the evidence III. PMID:28217572

  16. 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

  17. Oxygen Tension Is a Determinant of the Matrix-Forming Phenotype of Cultured Human Meniscal Fibrochondrocytes

    PubMed Central

    Adesida, Adetola B.; Mulet-Sierra, Aillette; Laouar, Leila; Jomha, Nadr M.

    2012-01-01

    Background Meniscal cartilage displays a poor repair capacity, especially when injury is located in the avascular region of the tissue. Cell-based tissue engineering strategies to generate functional meniscus substitutes is a promising approach to treat meniscus injuries. Meniscus fibrochondrocytes (MFC) can be used in this approach. However, MFC are unable to retain their phenotype when expanded in culture. In this study, we explored the effect of oxygen tension on MFC expansion and on their matrix-forming phenotype. Methodology/Principal Findings MFC were isolated from human menisci followed by basic fibroblast growth factor (FGF-2) mediated cell expansion in monolayer culture under normoxia (21%O2) or hypoxia (3%O2). Normoxia and hypoxia expanded MFC were seeded on to a collagen scaffold. The MFC seeded scaffolds (constructs) were cultured in a serum free chondrogenic medium for 3 weeks under normoxia and hypoxia. Constructs containing normoxia-expanded MFC were subsequently cultured under normoxia while those formed from hypoxia-expanded MFC were subsequently cultured under hypoxia. After 3 weeks of in vitro culture, the constructs were assessed biochemically, histologically and for gene expression via real-time reverse transcription-PCR assays. The results showed that constructs under normoxia produced a matrix with enhanced mRNA ratio (3.5-fold higher; p<0.001) of collagen type II to I. This was confirmed by enhanced deposition of collagen II using immuno-histochemistry. Furthermore, the constructs under hypoxia produced a matrix with higher mRNA ratio of aggrecan to versican (3.5-fold, p<0.05). However, both constructs had the same capacity to produce a glycosaminoglycan (GAG) –specific extracellular matrix. Conclusions Our data provide evidence that oxygen tension is a key player in determining the matrix phenotype of cultured MFC. These findings suggest that the use of normal and low oxygen tension during MFC expansion and subsequent neo-tissue formation

  18. Os subtibiale: Mimicking medial malleolar fracture.

    PubMed

    Topal, Murat; Köse, Ahmet; Dinçer, Recep; Baran, Tuncay; Köse, Mehmet; Çağatay Engin, M

    2017-06-01

    There are numerous sesamoids and accessory ossicles around the foot which can easily be misdiagnosed as fractures. Os subtibiale is a very rare normal variant of the medial malleolus which is usually diagnosed incidentally in routine ankle radiographs. In this report, we present a case series of 3 patients with os subtibiale who were admitted to the emergency department with ankle sprains and misdiagnosed as medial malleolar fractures. We would like to raise awareness to the very rare and usually asymptomatic os subtibiale as a diagnostic pitfall. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Intra-articular administration of xenogeneic neonatal Mesenchymal Stromal Cells early after meniscal injury down-regulates metalloproteinase gene expression in synovium and prevents cartilage degradation in a rabbit model of osteoarthritis.

    PubMed

    Saulnier, N; Viguier, E; Perrier-Groult, E; Chenu, C; Pillet, E; Roger, T; Maddens, S; Boulocher, C

    2015-01-01

    The anti-inflammatory and anti-catabolic effects of neonatal Mesenchymal Stromal Cell (MSC) were investigated in a xenogeneic model of mild osteoarthritis (OA). The paracrine properties of MSC on synoviocytes were further investigated in vitro. OA was induced by medial meniscal release (MMR) in 30 rabbit knees. A single early (day 3) or delayed (day 15) intra-articular (IA) injection of MSC isolated from equine Umbilical Cord Wharton's jelly (UC-MSC) was performed. Rabbits were euthanized on days 15 or 56. OA grading was performed and gene expression of inflammatory cytokines and metalloproteinases was measured in synovial tissue. Paracrine effects of UC-MSC were investigated using UC-conditioned vs control medium on rabbit primary synoviocytes stimulated with interleukin 1 beta in vitro. No adverse local or systemic responses were observed clinically after xenogeneic UC-MSC injection. At study end point, cartilage fibrillation was lower in early treatment than in delayed treatment group. Cellular infiltrate was observed in the synovium of both UC-MSC groups. OA synovium exhibited a reduced expression of metalloproteinases-1, -3, -13 in the early cell-treated group at d56. In vitro, UC-conditioned medium exerted anti-inflammatory and anti-catabolic effects on synoviocytes exposed to pro-inflammatory stimulus. Early IA injection of equine UC-MSC was effective in preventing OA signs in rabbit knees following MMR. UC-MSC target the synovium and modulate the gene expression pattern of synoviocytes to promote an anti-catabolic environment. This confirms the synovium is a major target and mediator of MSC therapy, modulating the expression of matrix-degrading enzymes. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  20. Effect of partial medial meniscectomy on anterior tibial translation in stable knees: a prospective controlled study on 32 patients

    PubMed Central

    2013-01-01

    Background Quantitative measurement of anterior translation of the tibia (ATT) by KT 1000 is used mainly to provide an objective assessment of knee laxity after anterior cruciate ligament (ACL) tears or ACL reconstructions. Only few papers described its use after menisectomies in knees with intact ACL. The objective of this paper is to determine whether partial medial meniscectomies could induce significant immediate post-operative ATT. Methods Thirty-two patients with a diagnosis of partial medial meniscal tear limited to the posterior horn and documented with magnetic resonance imaging (MRI) were assessed under anesthesia before and immediately after arthroscopic meniscectomy. The assessment was performed by the same examiner by means of the MEDmetric(R) KT-1000 instrument using manual maximum (MM) force. The opposite knees were also assessed. Results There is a significant difference between pre and post-operative KT MM mean values for the operated knees (CI: -3.933953 to −2.947297, p < 0.0001). No significance was found between the mean values for the contralateral knees before and after the completion of the menisectomy on the operated knees (p = 0.4). For the operated knees, 14 (43.75%) had a side-to-side difference between pre-and post-operative values of more than 3 mm, whereas for the contralateral knees, only 2 (6%) had the same. Conclusion Less than half of operated knees showed significant side-to-side difference values of ATT (>3 mm), immediately after meniscectomies in unconscious patients. Our values might reflect a temporarily increase of anterior laxity under specific conditions but whether a significant laxity remains in some knees, such changes may lead to higher cartilage loading and early osteoarthritis. PMID:24499538

  1. Adult human mesenchymal stem cells delivered via intra-articular injection to the knee following partial medial meniscectomy: a randomized, double-blind, controlled study.

    PubMed

    Vangsness, C Thomas; Farr, Jack; Boyd, Joel; Dellaero, David T; Mills, C Randal; LeRoux-Williams, Michelle

    2014-01-15

    There are limited treatment options for tissue restoration and the prevention of degenerative changes in the knee. Stem cells have been a focus of intense preclinical research into tissue regeneration but limited clinical investigation. In a randomized, double-blind, controlled study, the safety of the intra-articular injection of human mesenchymal stem cells into the knee, the ability of mesenchymal stem cells to promote meniscus regeneration following partial meniscectomy, and the effects of mesenchymal stem cells on osteoarthritic changes in the knee were investigated. A total of fifty-five patients at seven institutions underwent a partial medial meniscectomy. A single superolateral knee injection was given within seven to ten days after the meniscectomy. Patients were randomized to one of three treatment groups: Group A, in which patients received an injection of 50 × 10⁶ allogeneic mesenchymal stem cells; Group B, 150 × 10⁶ allogeneic mesenchymal stem cells; and the control group, a sodium hyaluronate (hyaluronic acid/hyaluronan) vehicle control. Patients were followed to evaluate safety, meniscus regeneration, the overall condition of the knee joint, and clinical outcomes at intervals through two years. Evaluations included sequential magnetic resonance imaging (MRI). No ectopic tissue formation or clinically important safety issues were identified. There was significantly increased meniscal volume (defined a priori as a 15% threshold) determined by quantitative MRI in 24% of patients in Group A and 6% in Group B at twelve months post meniscectomy (p = 0.022). No patients in the control group met the 15% threshold for increased meniscal volume. Patients with osteoarthritic changes who received mesenchymal stem cells experienced a significant reduction in pain compared with those who received the control, on the basis of visual analog scale assessments. There was evidence of meniscus regeneration and improvement in knee pain following treatment with

  2. Medial Canthoplasty Combined with Conjunctivodacryocystorhinostomy for the Treatment of Delayed Medial Telecanthal Deformity

    PubMed Central

    Sun, Hua; Li, Yang; Huang, Qian; Ding, Jing-Wen; Hou, Zhi-Jia; Li, Dong-Mei

    2017-01-01

    Background: Rupture of the medial canthal ligament can be caused by many events. It remains a challenge to rebuild the drainage system and restore the function. The aim of this study was to evaluate the clinical efficacy of medial canthoplasty combined with conjunctivodacryocystorhinostomy (CDCR) in patients with medial telecanthal deformities and lacrimal drainage system damage. Methods: Twenty-two patients (22 eyes) treated with medial canthoplasty and CDCR during June 2012 to June 2014 were included in this retrospective study. For all patients, a self-tapping, titanium, low-profile head microscrew was drilled into the solid bone on the posterior aspect of the anterior lacrimal crest at the attachment position of the medial canthal ligament. Medpor-coated tear drainage tubes were applied. Distance of patient's lateral displacement before and after operation was recorded and compared. The complications of CDCR were described. Results: Before the surgery, distance of patient's canthal displacement was 4–6 mm. The canthal distance between two eyes of patients with surgery was 1 mm or less. Among patients with CDCR, four patients had proximal obstruction and two patients had distal obstruction. Five patients had tube malposition, for example, tube extrusion 1–3 months after surgery. Conclusions: Medial canthoplasty combined with CDCR is an effective surgical method for treatment of patients with medial telecanthal deformity and lacrimal drainage system obstruction. The study indicates that medial canthoplasty combined with CDCR surgery rebuilds normal appearance of eyelid and contour of the medial canthus and successfully repairs the function of the lacrimal drainage system. PMID:28303853

  3. [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. Georg Thieme Verlag KG Stuttgart · New York.

  4. Medial Patellar Instability: Treatment and Outcomes

    PubMed Central

    Moatshe, Gilbert; Cram, Tyler R.; Chahla, Jorge; Cinque, Mark E.; Godin, Jonathan A.; LaPrade, Robert F.

    2017-01-01

    Background: Historically, a lateral retinacular release was one of the primary surgical interventions used to treat lateral patellar instability. However, disruption of the lateral structures during this procedure has been associated with medial instability of the patella. Hypothesis: We hypothesize that good to excellent outcomes can be achieved at midterm follow-up after lateral patellotibial ligament reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Thirteen patients were treated for medial patellar instability with a lateral patellotibial ligament reconstruction between May 2011 and December 2013 by a single surgeon. All patients had previously undergone a lateral release procedure and had symptomatic medial patellar instability. Patients were evaluated using patient-reported outcome scores at a minimum of 2 years postsurgery. Results: The mean Lysholm score improved from 45.6 (range, 11-76) to 71.9 (range, 30-91). The median preoperative Tegner activity scale score was 3 (range, 1-7), while the median postoperative score was 4 (range, 1-9). The median Western Ontario and McMaster Universities Arthritis Index (WOMAC) total score improved from 38 (range, 1-57) preoperatively to 6 postoperatively (range, 0-52). The mean patient satisfaction postoperatively was 8.2 (range, 5-10). Conclusion: Significantly improved outcomes can be achieved at midterm follow-up with a low rate of complications when reconstructing the lateral patellotibial ligament in the setting of iatrogenic medial patellar instability. PMID:28451613

  5. 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…

  6. 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…

  7. 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

  8. Sports injury to a bipartite medial cuneiform in a child.

    PubMed

    Eves, Timothy B; Ahmad, Mudussar A; Oddy, Michael J

    2014-01-01

    We report the case of an 11-year-old boy who had sustained a soccer injury to his mid-foot. Plain radiography did not reveal any fracture to account for the severity of his symptoms or his inability to bear weight. Magnetic resonance imaging was undertaken and demonstrated the medial cuneiform to be a bipartite bone consisting of 2 ossicles connected by a synchondrosis. No acute fracture or diastasis of the bipartite bone was demonstrated; however, significant bone marrow edema was noted, corresponding to the site of the injury and his clinical point bony tenderness. This anatomic variant should be considered as a rare differential diagnosis in the skeletally immature foot. The injury was treated nonoperatively with a non-weightbearing cast and pneumatic walker immobilization, with successful resolution of his symptoms and a return to sports activity by 4 months after injury.

  9. Myositis ossificans traumatica of temporalis and medial pterygoid muscle

    PubMed Central

    Reddy, Shyam Prasad D; Prakash, Ajay P; Keerthi, M; Rao, Brahmaji J

    2014-01-01

    Myositis ossificans is a rare disease that is characterized by bone deposition in the muscle or soft tissues. Myositis ossificans of the masticatory muscles is an uncommon finding. The condition is benign and results in heterotopic bone formation in the muscles of mastication, usually producing limitation of opening of the jaws. It is important to know the exact cause of the limitation of opening of the jaws for successful treatment. Computed tomographic scan and panoramic radiographs along with histological findings are essential diagnostic aids for evaluating conditions such as myositis ossificans. A rare case of myositis ossificans traumatica of temporalis and medial pterygoid muscle is presented here along with the discussion of clinical, radiological and histological features. The present case emphasizes not only on the importance of considering myositis ossificans in the differential diagnosis of limitation of opening of the jaws but also on the improvement of the overall mouth opening and treatment results. PMID:25328311

  10. Myositis ossificans traumatica of temporalis and medial pterygoid muscle.

    PubMed

    Reddy, Shyam Prasad D; Prakash, Ajay P; Keerthi, M; Rao, Brahmaji J

    2014-05-01

    Myositis ossificans is a rare disease that is characterized by bone deposition in the muscle or soft tissues. Myositis ossificans of the masticatory muscles is an uncommon finding. The condition is benign and results in heterotopic bone formation in the muscles of mastication, usually producing limitation of opening of the jaws. It is important to know the exact cause of the limitation of opening of the jaws for successful treatment. Computed tomographic scan and panoramic radiographs along with histological findings are essential diagnostic aids for evaluating conditions such as myositis ossificans. A rare case of myositis ossificans traumatica of temporalis and medial pterygoid muscle is presented here along with the discussion of clinical, radiological and histological features. The present case emphasizes not only on the importance of considering myositis ossificans in the differential diagnosis of limitation of opening of the jaws but also on the improvement of the overall mouth opening and treatment results.

  11. Meniscal allograft transplantation. Part 1: systematic review of graft biology, graft shrinkage, graft extrusion, graft sizing, and graft fixation.

    PubMed

    Samitier, Gonzalo; Alentorn-Geli, Eduard; Taylor, Dean C; Rill, Brian; Lock, Terrence; Moutzouros, Vasilius; Kolowich, Patricia

    2015-01-01

    To provide a systematic review of the literature regarding five topics in meniscal allograft transplantation: graft biology, shrinkage, extrusion, sizing, and fixation. A systematic literature search was conducted using the PubMed (MEDLINE), ScienceDirect, and EBSCO-CINAHL databases. Articles were classified only in one topic, but information contained could be reported into other topics. Information was classified according to type of study (animal, in vitro human, and in vivo human) and level of evidence (for in vivo human studies). Sixty-two studies were finally included: 30 biology, 3 graft shrinkage, 11 graft extrusion, 17 graft size, and 6 graft fixation (some studies were categorized in more than one topic). These studies corresponded to 22 animal studies, 22 in vitro human studies, and 23 in vivo human studies (7 level II, 10 level III, and 6 level IV). The principal conclusions were as follows: (a) Donor cells decrease after MAT and grafts are repopulated with host cells form synovium; (b) graft preservation alters collagen network (deep freezing) and causes cell apoptosis with loss of viable cells (cryopreservation); (c) graft shrinkage occurs mainly in lyophilized and gamma-irradiated grafts (less with cryopreservation); (d) graft extrusion is common but has no clinical/functional implications; (e) overall, MRI is not superior to plain radiograph for graft sizing; (f) graft width size matching is more important than length size matching; (g) height appears to be the most important factor influencing meniscal size; (h) bone fixation better restores contact mechanics than suture fixation, but there are no differences for pullout strength or functional results; and (i) suture fixation has more risk of graft extrusion compared to bone fixation. Systematic review of level II-IV studies, Level IV.

  12. Meniscal repair in vivo using human chondrocyte-seeded PLGA mesh scaffold pretreated with platelet-rich plasma.

    PubMed

    Kwak, Hong Suk; Nam, Jinwoo; Lee, Ji-Hye; Kim, Hee Joong; Yoo, Jeong Joon

    2017-02-01

    The objective of this study was to test the hypothesis that platelet-rich plasma (PRP) pretreatment on a poly-lactic-co-glycolic acid (PLGA) mesh scaffold enhances the healing capacity of the meniscus with human chondrocyte-seeded scaffolds in vivo, even when the seeded number of cells was reduced from 10 million to one million. A flexible PLGA mesh scaffold was pretreated with PRP using a centrifugal technique. One million human articular chondrocytes were seeded onto the scaffold by dynamic oscillation. After 7 days, scaffolds were placed between human meniscal discs and were implanted subcutaneously in nude mice for 6 weeks (n = 16/group). Fluorescence microscopy demonstrated uniform attachment of the chondrocytes throughout the scaffolds 24 h following seeding. Cell attachment analysis revealed a significantly increased number of chondrocytes on PRP-pretreated than non-treated scaffolds (p < 0.05). Field emission scanning electron microscopy revealed chondrocytes attached to the PRP-pretreated scaffolds interconnecting their cellular processes with the fibrin network at 24 h and day 7 of culture. Of the 16 constructs containing PRP-pretreated scaffolds implanted in mice, six menisci healed completely, nine healed incompletely and one did not heal. Histological results from the 16 control constructs containing non-treated scaffolds revealed that none had healed completely, four healed incompletely and 12 did not heal. The histological outcome between the groups was significantly different (p < 0.05). These findings suggest that human articular chondrocytes on PRP-pretreated PLGA mesh scaffolds demonstrate increased cell attachment and enhance the healing capacity of meniscus with a reduced number of seeding cells in a meniscal repair mouse model. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Consequences of tibial tunnel reaming on the meniscal roots during cruciate ligament reconstruction in a cadaveric model, Part 2: The posterior cruciate ligament.

    PubMed

    LaPrade, Christopher M; Smith, Sean D; Rasmussen, Matthew T; Hamming, Mark G; Wijdicks, Coen A; Engebretsen, Lars; Feagin, John A; LaPrade, Robert F

    2015-01-01

    Recent emphasis has turned to reconstructing the posterior cruciate ligament (PCL) after injury. However, single-bundle PCL reconstruction of the anterolateral bundle may potentially injure the posterior meniscal roots. The purpose of this study was to determine if posterior meniscal root injuries occurred because of tunnel reaming for single-bundle PCL reconstruction. It was hypothesized that tibial tunnel reaming within the anterolateral bundle footprint during PCL reconstruction would result in clinically significant decreases in posteromedial (PM) root attachment areas and in ultimate failure strength for the PM root. Controlled laboratory study. Testing was performed on 12 matched pairs of human cadaveric knees. For each pair of knees, one knee was left intact, while the contralateral knee was prepared with a tibial tunnel placed 5 mm anterior to the center of the tibial PCL attachment and within the previously described footprint of the anterolateral bundle of the PCL for single-bundle PCL reconstruction. The attachment areas of the posterior meniscal roots were measured with a coordinate measuring device before and after PCL tunnel reaming. The posterior meniscal roots were then pulled to failure with a dynamic tensile testing machine. There was a significant mean decrease in the attachment area of the PM root (%Δ, 28%; 95% CI, 16-40) after PCL tunnel reaming compared with the intact state (P=.005). The mean ultimate failure strength of the native PM root (mean, 440 N; 95% CI, 347-534) was also significantly stronger (mean, 40%; 95% CI, 18-61; P=.005) than that of the PM root after PCL tunnel reaming (mean, 243 N; 95% CI, 176-309). No changes were found for the posterolateral (PL) root after PCL tunnel reaming. Tibial tunnel reaming for single-bundle PCL reconstruction in the anterolateral bundle footprint significantly reduced the ultimate failure strength and attachment area of the PM meniscal root. The attachment area and ultimate failure strength of the

  14. Isolated Medial Rectus Palsy: Rare Presentation of Mesencephalon Infarction.

    PubMed

    Yao, Yindan; Hong, Wenke; Fan, Zhenyi; Li, Da; Chang, Xianchao; Fan, Weinv

    2017-04-01

    Isolated medial rectus palsy due to mesencephalon lesion is extremely rare. We here describe a patient of midbrain infarction involving the medial rectus subnuclei presenting as isolated medial rectus palsy. Axial diffusion-weighted and coronal T2-weighted magnetic resonance imaging showed acute ischemic lesion in mesencephalon. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  15. 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.

  16. [SECOT consensus on medial femorotibial osteoarthritis].

    PubMed

    Moreno, A; Silvestre, A; Carpintero, P

    2013-01-01

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

  17. Osteoligamentous injuries of the medial ankle joint.

    PubMed

    Lötscher, P; Lang, T H; Zwicky, L; Hintermann, B; Knupp, M

    2015-12-01

    Injuries of the ankle joint have a high incidence in daily life and sports, thus, playing an important socioeconomic role. Therefore, proper diagnosis and adequate treatment are mandatory. While most of the ligament injuries around the ankle joint are treated conservatively, great controversy exists on how to treat deltoid ligament injuries in ankle fractures. Missed injuries and inadequate treatment of the medial ankle lead to inferior outcome with instability, progressive deformity, and ankle joint osteoarthritis.

  18. Medial septal lesion enhances general anesthesia response.

    PubMed

    Leung, L Stan; Ma, Jingyi; Shen, Bixia; Nachim, Ilan; Luo, Tao

    2013-09-01

    Electrolytic lesion of the medial septum, a basal forebrain nucleus that projects to the hippocampus, prolonged the emergence from general anesthesia in rats. Septal lesioned rats required a longer time to recover from a loss of righting reflex (LORR) and a loss of tail-pinch response after injectable (20 mg/kg i.p. pentobarbital, 5mg/kg i.v. propofol) or volatile (1.5% halothane, 2% isoflurane) anesthetic. When incremental doses of propofol were given i.p., septal lesioned rats as compared to control rats showed LORR at a lower dose of propofol. Similarly, when the rats were exposed to increasing concentrations of isoflurane, the percent of rats showing LORR was leftward shifted for lesioned rats as compared to control rats. Septal lesioned rats as compared to control rats showed decreased locomotor activity when exposed to 1.5% halothane. Lesion of the medial septum was confirmed by thionin-stained histological sections as well as loss of acetylcholinesterase (AchE) staining in the hippocampus, indicating a depletion of septohippocampal cholinergic afferents. Medial septal lesion resulted in a near complete loss of hippocampal theta rhythm during walking and a general decrease in power of the hippocampal EEG at all frequencies (0-100 Hz), during walking or immobility. It is concluded that lesion of medial septum, in part through a loss of septohippocampal cholinergic afferents, increased the anesthesia response to volatile and injectable general anesthetics, during both induction and emergence. It is suggested that the septohippocampal system participates in many components of general anesthesia including hypnosis, immobility, and analgesia.

  19. Osteochondrosis of the accessory ossification centre of the medial malleolus.

    PubMed

    Farsetti, Pasquale; Dragoni, Massimiliano; Potenza, Vito; Caterini, Roberto

    2015-01-01

    We report a case of a painful accessory ossification centre of the medial malleolus in an 11-year-old girl who was not involved in sports activities. The patient was treated conservatively, with complete clinical and radiographic healing of the medial malleolus 6 months after the first presentation. We ruled out the uncommon pathological conditions causing chronic pain in the medial malleolus during skeletal growth, such as traction apophysitis of the medial malleolus, osteochondrosis, osteochondritis or avascular necrosis of the distal tibial epiphysis. We speculate that this painful condition may be classified as an osteochondrosis of the accessory ossification centre of the medial malleolus.

  20. Variations in the origin of the medial calcaneal nerve.

    PubMed

    Dellon, A Lee; Kim, Jaesuk; Spaulding, Cecily M

    2002-02-01

    Previous anatomic studies of the medial heel region were done on embalmed human cadavers. Here, the innervation of the medial heel region was studied by dissecting living tissue with the use of 3.5-power loupe magnification during decompression of the medial ankle for tarsal tunnel syndrome in 85 feet. The medial heel was found to be innervated by just one medial calcaneal nerve in 37% of the feet, by two medial calcaneal nerves in 41%, by three medial calcaneal nerves in 19%, and by four medial calcaneal nerves in 3%. An origin for a medial calcaneal nerve from the medial plantar nerve was found in 46% of the feet. This nerve most often innervates the skin of the posteromedial arch, where it is at risk for injury during calcaneal spur removal or plantar fasciotomy. Knowledge of the variations in location of the medial calcaneal nerves may prevent neuroma formation during surgery and provide insight into the variability of heel symptoms associated with tarsal tunnel syndrome.

  1. 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

  2. Quantitative proteomics reveals regulatory differences in the chondrocyte secretome from human medial and lateral femoral condyles in osteoarthritic patients

    PubMed Central

    2013-01-01

    Background Osteoarthritis (OA) is a destructive joint disease and there are no known biomarkers available for an early diagnosis. To identify potential disease biomarkers and gain further insight into the disease mechanisms of OA we applied quantitative proteomics with SILAC technology on the secretomes from chondrocytes of OA knees, designated as high Mankin (HM) scored secretome. A quantitative comparison was made between the secretomes of the medial and lateral femur condyle chondrocytes in the same knee since the medial femur condyle is usually more affected in OA than the lateral condyle, which was confirmed by Mankin scoring. The medial/lateral comparison was also made on the secretomes from chondrocytes taken from one individual with no clinically apparent joint-disease, designated as low Mankin (LM) scored secretome. Results We identified 825 proteins in the HM secretome and 69 of these showed differential expression when comparing the medial and lateral femoral compartment. The LM scored femoral condyle showed early signs of OA in the medial compartment as assessed by Mankin score. We here report the identification and relative quantification of several proteins of interest for the OA disease mechanism e.g. CYTL1, DMD and STAB1 together with putative early disease markers e.g. TIMP1, PPP2CA and B2M. Conclusions The present study reveals differences in protein abundance between medial/lateral femur condyles in OA patients. These regulatory differences expand the knowledge regarding OA disease markers and mechanisms. PMID:24090399

  3. Synergistic effect of electrical conductivity and biomolecules on human meniscal cell attachment, growth and proliferation in poly-ε-caprolactone nanocomposite scaffolds.

    PubMed

    Gopinathan, Janarthanan; Pillai, Mamatha M; Sahanand, K Santosh; Rai, B K Dinakar; Selvakumar, Rajendran; Bhattacharyya, Amitava

    2017-07-13

    Poly-ε-caprolactone (PCL) based nanocomposite scaffolds with different concentrations of carbon nanofillers (carbon nanofibers (CNF), nanographite and exfoliated graphite) have been studied to investigate the effect of electrical conductivity and biomolecules supplementation for enhanced human meniscal cell attachment, growth and proliferation. Incorporation of carbon nanofillers was found to improve mechanical and electrical properties. CNF based nanocomposite scaffolds showed highest electrical conductivity with significant improvements in mechanical properties (more than 50% tensile strength increase than PCL with 10% (w/w) CNF). All nanocomposite scaffolds were subjected to cytotoxicity studies using primary meniscus cells. The nanocomposite scaffolds showing higher cell viability were selected and tested for meniscal cell attachment and proliferation assays such as total DNA content, extracellular matrix secretion, nuclear staining and cell attachment studies using scanning electron microscope. When an optimized combination of biomolecules is supplemented in the cell culture medium, synergistic effect of electrical conductivity and biomolecule combination is observed especially in case of highly conducting CNF (7.5% and 10% (w/w)) based nanocomposite scaffolds. Our findings suggest that electrically conductive scaffolds with optimized biomolecules in cell culture medium can be potentially used for successful human meniscal tissue engineering applications. © 2017 IOP Publishing Ltd.

  4. Management of medial-sided knee injuries, part 1: medial collateral ligament.

    PubMed

    Marchant, Milford H; Tibor, Lisa M; Sekiya, Jon K; Hardaker, William T; Garrett, William E; Taylor, Dean C

    2011-05-01

    The medial collateral ligament complex is a primary stabilizer that combines static and dynamic resistance to direct valgus stress while contributing significant restraints to rotatory motion and anterior-posterior translation. Varying opinions exist among investigators regarding injury classification and treatment algorithms. Whereas most agree that the majority of isolated medial collateral ligament complex injuries can be treated nonoperatively, isolated injuries with chronic instability and multiligament injuries may require operative intervention. Substantial confounding factors are present within published reports, making comparative analyses and systematic review challenging. This review focuses on the anatomy and biomechanics of the medial structures of the knee; it discusses the clinical evaluation of complex injuries; and it reviews nonoperative and operative treatment methods.

  5. Medially constrained deformable modeling for segmentation of branching medial structures: Application to aortic valve segmentation and morphometry.

    PubMed

    Pouch, Alison M; Tian, Sijie; Takebe, Manabu; Yuan, Jiefu; Gorman, Robert; Cheung, Albert T; Wang, Hongzhi; Jackson, Benjamin M; Gorman, Joseph H; Gorman, Robert C; Yushkevich, Paul A

    2015-12-01

    Deformable modeling with medial axis representation is a useful means of segmenting and parametrically describing the shape of anatomical structures in medical images. Continuous medial representation (cm-rep) is a "skeleton-first" approach to deformable medial modeling that explicitly parameterizes an object's medial axis and derives the object's boundary algorithmically. Although cm-rep has effectively been used to segment and model a number of anatomical structures with non-branching medial topologies, the framework is challenging to apply to objects with branching medial geometries since branch curves in the medial axis are difficult to parameterize. In this work, we demonstrate the first clinical application of a new "boundary-first" deformable medial modeling paradigm, wherein an object's boundary is explicitly described and constraints are imposed on boundary geometry to preserve the branching configuration of the medial axis during model deformation. This "boundary-first" framework is leveraged to segment and morphologically analyze the aortic valve apparatus in 3D echocardiographic images. Relative to manual tracing, segmentation with deformable medial modeling achieves a mean boundary error of 0.41 ± 0.10 mm (approximately one voxel) in 22 3DE images of normal aortic valves at systole. Deformable medial modeling is additionally demonstrated on pathological cases, including aortic stenosis, Marfan syndrome, and bicuspid aortic valve disease. This study demonstrates a promising approach for quantitative 3DE analysis of aortic valve morphology. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Post-ablative reconstruction of the medial canthus and medial orbital wall using conchal cartilage graft with three illustrative cases.

    PubMed

    Dagregorio, G; Darsonval, V

    2005-12-01

    When the medial third of the upper or lower eyelid has to be reconstructed after full-thickness tumour excision, we usually use Hübner tarsomarginal grafts, but when medial canthal lesions spread to the medial orbital wall without invading the orbital margin, conchal graft becomes our first surgical option. Previously reported solutions to this difficult problem are few and concern more directly medial orbital wall fractures. We found no article dealing specifically with the use of conchal graft in post-ablative reconstruction of the medial orbital wall. Nevertheless the concha presents great advantages over bone grafting or rib cartilage, because it is more flexible and malleable. And it is less prone to extrusion or infection as may be allografts implants. It is a very effective way to repair medial orbital defects, but graft reorientation must be perfect to match exactly the medial orbital wall concavity.

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

    SciTech Connect

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

    2010-03-24

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

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

    PubMed Central

    Einstein, Daniel R.; Dyedov, Vladimir

    2010-01-01

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

  9. 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…

  10. 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…

  11. The lateral column lengthening and medial column stabilization procedures.

    PubMed

    Chi, T D; Toolan, B C; Sangeorzan, B J; Hansen, S T

    1999-08-01

    The results of medial column stabilization, lateral column lengthening, and combined medial and lateral procedures were reviewed in the treatment of adult acquired flatfoot secondary to posterior tibialis tendon insufficiency. All bony procedures were accompanied by transfer of the flexor digitorum longus tendon to the medial cuneiform or stump of the posterior tibialis tendon and tendoachilles lengthening or gastrocnemius recession. Medial column fusion was performed for naviculocuneiform and cuneiform first metatarsal sag; lateral column lengthening was performed for calcaneovalgus deformity with a flat pitch angle; and combined procedures were performed for complex combined deformities. At 1 to 4 year followup of 65 feet, 88% of the feet that had lateral column lengthening, 80% that had medial column stabilization, and 88% of the feet that had medial and lateral procedures had a decrease in pain or were pain free. The lateral talar first metatarsal angle improved by 16 degrees in the patients in the lateral column lengthening group, 20 degrees in the patients in the medial column stabilization group, and 24 degrees in the patients in the combined medial and lateral procedures group. The anteroposterior talonavicular coverage angle improved by 14 degrees in the patients in the lateral column lengthening group, 10 degrees in the patients in the medial column stabilization group, and 14 degrees in the patients in the combined medial and lateral procedures group. These techniques effectively correct deformity without disrupting the essential joints of the hindfoot and midfoot.

  12. Content Representation in the Human Medial Temporal Lobe

    PubMed Central

    Liang, Jackson C.; Wagner, Anthony D.

    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

  13. Medial unicondylar knee arthroplasty: technical pearls

    PubMed Central

    BONIFORTI, FILIPPO

    2015-01-01

    Unicondylar knee arthroplasty implantation is extremely demanding as the prosthesis needs to be integrated in the natural anatomy of the knee. It ensures the integrity of the natural knee kinematic. Some studies and registries data have shown lower success rate in comparison with total knee arthroplasty, and patient-related factors may have an impact on outcome. While, better results have been published by high volume centres. The indications for surgery should be reconsidered critically, even if medial osteoarthritis of the knee remains the most common. This article sets out the diagnostic, and surgical steps in order to fine tuning the unicompartmental replacement of the knee. PMID:26605256

  14. Medial knee joint loading increases in those who respond to hyaluronan injection for medial knee osteoarthritis.

    PubMed

    Briem, Kristin; Axe, Michael J; Snyder-Mackler, Lynn

    2009-11-01

    Knee osteoarthritis (OA) is a cause of decline in function and the medial compartment is often affected. Intraarticular injection of hyaluronic acid (HA) is indicated as a symptom modifying treatment with at least 6 months passing between consecutive injection series. The effects of HA injection on gait variables have not been extensively examined. Therefore, our objective was to investigate the effects of HA injection on gait in people with medial knee OA. Twenty-seven subjects were included; each was tested prior to treatment (baseline), no later than 3 weeks following the last injection (post-HA), and again 5 months after treatment ended (follow-up). Responder criteria were defined to identify responders and non-responders. Subjects underwent 3D gait analysis, muscle activity was sampled, and co-contraction indices were calculated. Responders experienced increased peak knee adduction moments post-HA, whereas non-responders did not. Improved self-report scores were associated with increased knee adduction moments and increased medial co-contraction. Pain relief may result in higher loading onto the already vulnerable medial compartment due to changes in lower limb mechanics and muscle activation patterns. Eventually this may result in a more rapid progression of joint deterioration.

  15. Biomechanical consequences of patellar component medialization in total knee arthroplasty.

    PubMed

    Anglin, Carolyn; Brimacombe, Jill M; Wilson, David R; Masri, Bassam A; Greidanus, Nelson V; Tonetti, Jérôme; Hodgson, Antony J

    2010-08-01

    The optimal amount of patellar component medialization in knee arthroplasty is unknown. We measured the impact, on patellofemoral kinematics and contact force distribution, of 0.0-, 2.5-, and 5.0-mm patellar component medialization in 7 cadaveric specimens implanted with knee arthroplasty components. The knees were flexed dynamically in a weight-bearing rig. Medialization led to lateral shift of the patellar bone, slight medial shift of the patellar component in the femoral groove, lateral tilt of the patella, reduced patellofemoral contact force in later flexion, and lateral shift of the center of pressure in early flexion. Effects on shift and tilt were proportional to the amount of medialization. As a result of this investigation, we recommend medializing the patellar component slightly-on the order of 2.5 mm. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  16. [Medial epicondylitis. Etiology, diagnosis, therapeutic modalities].

    PubMed

    Tschantz, P; Meine, J

    1993-01-01

    Medial epicondylitis is rather uncommon, less frequent than external epicondylitis. For this reason, the diagnosis is thought of rather late. While taking the history, one should try to find out the possible causative effects. Symptoms of irritation of the cubital nerve, which are present in one out of five cases should be looked for. Several sports such as baseball, javelin or weight throwing, volleyball, climbing, tennis, golf, which need a strong flexion of the hand and fingers can induce this condition. However, in more than half of our patients, sports or professional activities were not in cause. The majority were housewives and do-it-yourself enthusiasts. Among our 55 operated cases, out of which few had professional or sports activities, we did not encounter during the operation the macroscopic tendinous lesions that are sometimes described by some authors. The treatment should be conservative in all cases. This includes rest, anti-inflammatory drugs, physiotherapy, muscular stretching, immobilisation in a cast, steroid infiltrations. One patient out of ten will have to be operated on. The operative techniques differ on some details, but they all include the desinsertion of the flexor muscles on the medial epicondyle. When there are clinical signs of irritation of the cubital nerve, it should be transposed anteriorly. The result of these operations is good in more than 90 per cent of the cases. However, a come back to professional sport can take as long as 8 months.

  17. Cartilage Delamination Flap Mimicking a Torn Medial Meniscus

    PubMed Central

    Bin Abd Razak, Hamid Rahmatullah; Amit Kanta, Mitra

    2016-01-01

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

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

    PubMed

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

    1982-01-01

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

  19. Medial Prefrontal-Medial Temporal Theta Phase Coupling in Dynamic Spatial Imagery.

    PubMed

    Kaplan, Raphael; Bush, Daniel; Bisby, James A; Horner, Aidan J; Meyer, Sofie S; Burgess, Neil

    2017-03-01

    Hippocampal-medial prefrontal interactions are thought to play a crucial role in mental simulation. Notably, the frontal midline/medial pFC (mPFC) theta rhythm in humans has been linked to introspective thought and working memory. In parallel, theta rhythms have been proposed to coordinate processing in the medial temporal cortex, retrosplenial cortex (RSc), and parietal cortex during the movement of viewpoint in imagery, extending their association with physical movement in rodent models. Here, we used noninvasive whole-head MEG to investigate theta oscillatory power and phase-locking during the 18-sec postencoding delay period of a spatial working memory task, in which participants imagined previously learned object sequences either on a blank background (object maintenance), from a first-person viewpoint in a scene (static imagery), or moving along a path past the objects (dynamic imagery). We found increases in 4- to 7-Hz theta power in mPFC when comparing the delay period with a preencoding baseline. We then examined whether the mPFC theta rhythm was phase-coupled with ongoing theta oscillations elsewhere in the brain. The same mPFC region showed significantly higher theta phase coupling with the posterior medial temporal lobe/RSc for dynamic imagery versus either object maintenance or static imagery. mPFC theta phase coupling was not observed with any other brain region. These results implicate oscillatory coupling between mPFC and medial temporal lobe/RSc theta rhythms in the dynamic mental exploration of imagined scenes.

  20. Conserved fMRI and LFP signals during new associative learning in the human and macaque monkey medial temporal lobe

    PubMed Central

    Hargreaves, Eric L.; Mattfeld, Aaron T.; Stark, Craig E.; Suzuki, Wendy A.

    2012-01-01

    SUMMARY We measured LFP and BOLD fMRI in the medial temporal lobes of monkeys and humans, respectively, as they performed the same conditional motor associative learning task. Parallel analyses were used to examine both datasets. Despite significantly faster learning in humans relative to monkeys, we found equivalent neural signals differentiating new versus highly familiar stimuli, first stimulus presentation, trial outcome and learning strength in the entorhinal cortex and hippocampus of both species. Thus, the use of parallel behavioral tasks and analyses in monkeys and humans revealed conserved patterns of neural activity across the medial temporal lobe during an associative learning task. PMID:22632731

  1. Diagnostic value of ultrasonography for clinical medial epicondylitis.

    PubMed

    Park, Gi-Young; Lee, Sung-Moon; Lee, Michael Y

    2008-04-01

    To assess the ultrasonographic findings and to evaluate the value of ultrasonography as a diagnostic method for detecting clinical medial epicondylitis. A prospective, single-blind study. An outpatient rehabilitation clinic in a tertiary university hospital. Twenty-one elbows from 18 patients with clinical medial epicondylitis and 25 elbows without medial epicondylitis were evaluated. Not applicable. The clinical diagnosis of medial epicondylitis was based on the patient's symptoms and clinical signs in a physical examination performed by a physiatrist. An experienced radiologist made the real-time ultrasonographic diagnosis based on the detection of at least one of the following abnormal findings: a focal hypoechoic or anechoic area, tendon nonvisualization, intratendinous calcifications, and cortical irregularity. Ultrasonography revealed positive findings in 20 of 21 elbows with medial epicondylitis and was negative in 23 of 25 without medial epicondylitis. Ultrasonography showed sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for clinical medial epicondylitis of 95.2%, 92%, 93.5%, 90.9%, and 95.8%, respectively. Tendinosis was observed in 15 elbows, and a partial-thickness tear, including 1 intrasubstance tear, was detected in 5 elbows. The most common ultrasonographic abnormality was a focal echogenic abnormality (15 hypoechoic, 5 anechoic) of the tendons. Our results indicate that ultrasonography is informative and accurate for the detection of clinical medial epicondylitis. Therefore, ultrasonography should be considered as an initial imaging method for evaluating medial epicondylitis.

  2. Medial and Lateral Discoid Menisci of Both Knees

    PubMed Central

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

    2016-01-01

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

  3. Mechanical Integrity of a Decellularized and Laser Drilled Medial Meniscus.

    PubMed

    Lakes, Emily H; Matuska, Andrea M; McFetridge, Peter S; Allen, Kyle D

    2016-03-01

    Since the meniscus has limited capacity to self-repair, creating a long-lasting meniscus replacement may help reduce the incidence of osteoarthritis (OA) after meniscus damage. As a first step toward this goal, this study evaluated the mechanical integrity of a decellularized, laser drilled (LD) meniscus as a potential scaffold for meniscal engineering. To evaluate the decellularization process, 24 porcine menisci were processed such that one half remained native tissue, while the other half was decellularized in sodium dodecyl sulphate (SDS). To evaluate the laser drilling process, 24 additional menisci were decellularized, with one half remaining intact while the other half was LD. Decellularization did not affect the tensile properties, but had significant effects on the cyclic compressive hysteresis and unconfined compressive stress relaxation. Laser drilling decreased the Young's modulus and instantaneous stress during unconfined stress relaxation and the circumferential ultimate strength during tensile testing. However, the losses in mechanical integrity in the LD menisci were generally smaller than the variance observed between samples, and thus, the material properties for the LD tissue remained within a physiological range. In the future, optimization of laser drilling patterns may improve these material properties. Moreover, reseeding the construct with cells may further improve the mechanical properties prior to implantation. As such, this work serves as a proof of concept for generating decellularized, LD menisci scaffolds for the purposes of meniscal engineering.

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

    PubMed Central

    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.

    2016-01-01

    Pluripotent stem cells (PSC) 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 CD34+CD38−/loCD90+CD45+GPI-80+ foetal liver (FL) HSC immunophenotype, but displayed 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, retinoic acid signalling-induced medial HOXA gene expression marks the establishment of the definitive HSC fate and controls HSC identity and function. PMID:27183470

  5. Medialized repair for retracted rotator cuff tears.

    PubMed

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

    2017-08-01

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

  6. An unusually medial axillary arch muscle.

    PubMed Central

    Dharap, A

    1994-01-01

    In the left upper limb of an adult male cadaver a triangular muscular slip, 3.5 cm long and 2.5 cm wide, arose from the lower border of latissimus dorsi just proximal to its tendon of insertion. It was inserted by a slender 6 cm long tendon mainly into the coracoid process of the scapula. Three short fibrous strands radiated from this slender tendon to gain attachments to pectoralis minor and the common tendon of origin of the short head of biceps brachii and coracobrachialis. In addition 2 flat tendinous bands attached the margin of this muscular slip to teres major. The thoracodorsal nerve entered the main bulk of latissimus dorsi close to the muscular slip but did not supply a separate branch to the latter. This is an axillary arch muscle in an unusually medial location. Images Fig. 1 Fig. 2 PMID:7928652

  7. Revision Gore-Tex medialization laryngoplasty.

    PubMed

    Cohen, Jacob T; Bates, Dwight D; Postma, Gregory N

    2004-09-01

    To evaluate the indications, results, and safety of revision Gore-Tex medialization laryngoplasty (GML). A retrospective chart review of 156 patients that underwent GML procedures between the years 1998-2002. Study population consisted of those patients who required revision surgery for any reason. Sixteen patients required 22 revision procedures. Indications for revision were divided into 2 groups, complications and glottal closure problems. Complications included extruded or displaced implants (n = 4). The most common glottal closure problem was undercorrection (n = 9). Others included anterior overcorrection (n = 1) and persistent posterior glottal gap (n = 2). Revision procedures included GML (n = 9), injection augmentation (n = 9), endoscopic implant removal (n = 2), and arytenoid adduction (n = 2). In patients with glottal closure problems, the GCI improved in all 10 and the voice rating scale improved in 9. Reasons for revision of GML are variable, the most common being undercorrection. A variety of safe, effective revision techniques are available with a high success rate.

  8. Motor unit organization of human medial gastrocnemius.

    PubMed Central

    Garnett, R A; O'Donovan, M J; Stephens, J A; Taylor, A

    1979-01-01

    1. The properties of fifty-seven motor units in human medial gastrocnemius have been studied using controlled intramuscular microstimulation, glycogen depletion and muscle biopsy. 2. Motor units could be divided into three classes on the basis of their mechanical properties. Type S units were slow, small and fatigue resistant. Type FR units were fast, intermediate in size, and fatigue resistant. Type FF units were fast, large and fatigable. 3. Glycogen depletion of a number of type S and FF units revealed them to be composed of type 1 and type 2b muscle fibres respectively. 4. The results suggest that during slowly increasing voluntary contractions where units are recruited in order of size, type 1 and 2a muscle fibres would be employed at low force levels followed by type 2b muscle fibres in stronger contractions. Images Fig. 5 Fig. 6 PMID:430414

  9. Motor unit organization of human medial gastrocnemius.

    PubMed

    Garnett, R A; O'Donovan, M J; Stephens, J A; Taylor, A

    1979-02-01

    1. The properties of fifty-seven motor units in human medial gastrocnemius have been studied using controlled intramuscular microstimulation, glycogen depletion and muscle biopsy. 2. Motor units could be divided into three classes on the basis of their mechanical properties. Type S units were slow, small and fatigue resistant. Type FR units were fast, intermediate in size, and fatigue resistant. Type FF units were fast, large and fatigable. 3. Glycogen depletion of a number of type S and FF units revealed them to be composed of type 1 and type 2b muscle fibres respectively. 4. The results suggest that during slowly increasing voluntary contractions where units are recruited in order of size, type 1 and 2a muscle fibres would be employed at low force levels followed by type 2b muscle fibres in stronger contractions.

  10. Medial humeral epicondylitis in clinically affected cats.

    PubMed

    Streubel, Ronny; Bilzer, Thomas; Grest, Paula; Damur, Daniel; Montavon, Pierre M

    2015-10-01

    To describe the clinical signs and histologic changes in cats clinically affected with medial humeral epicondylitis (MHE) and evaluate long-term outcome after either conservative or surgical treatment. Prospective cohort study. Client-owned cats (n = 17) with MHE. Cats diagnosed with MHE, based on clinical signs, radiographs and computed tomography (CT), were prospectively recruited. Cats were treated conservatively for an initial 4 weeks, followed by either surgery or continued conservative treatment. Followup examinations were performed at 6 and 12 weeks and at 6-49 months. Cats had a mean age of 10.3 years and presented for chronic lameness. Examination revealed pain on palpation caudodistal to the medial epicondyle and by exerting antebrachial supination/pronation with elbow and carpal flexion. Lameness was restricted to 1 limb although CT revealed bilateral disease in 11/17 cats. Free mineralized joint bodies were identified in 9/17 cats. Nine cats were treated surgically and 8 cats were treated conservatively. Intraoperative findings included new bone formation at the origin of the humeral head of the flexor carpi ulnaris muscle with displacement and adhesions of the ulnar nerve. Microscopic examination revealed neurogenic myopathy in 4/9 cats treated surgically. Seven of 9 cats treated surgically were free from lameness by 12 weeks. Seven of 8 cats treated conservatively were chronically lame throughout the study. Cats with forelimb lameness should be evaluated for MHE. This condition is associated with free joint bodies and neurogenic myopathy. Surgical treatment is associated with excellent outcome in the majority of cats. © Copyright 2015 by The American College of Veterinary Surgeons.

  11. Forefoot flexibility and medial tibial stress syndrome.

    PubMed

    Kudo, Shintarou; Hatanaka, Yasuhiko

    2015-12-01

    To investigate the association between medial tibial stress syndrome (MTSS) and morphology and flexibility of the foot arches. 131 feet from 74 healthy subjects and 31 feet from 27 patients with MTSS were classified as normal feet (n=78 in 40 subjects), flat feet (n=53 in 34 subjects), or MTSS feet (n=31 in 27 patients). The medial longitudinal arch (MLA) ratio and the transverse arch length (TAL) were measured in both rearfoot and forefoot loading positions. The difference between the 2 positions indicated the flexibility of the MLA (diff-MLA ratio) and the transverse arch (diff- TAL). The MLA ratio was higher in normal feet than MTSS feet or flat feet (15.1% vs. 12.8% vs. 12.3%, p<0.001). The diff-TAL was lower in MTSS feet than normal feet or flat feet (0.4% vs. 0.8% vs. 0.9%, p<0.001]). The 3 groups were comparable in terms of the diff-MLA ratio and the TAL. Respectively for the MLA ratio and the diff-TAL, the cut-off value was 11.9% and 0.61% based on the Youden index. The sensitivity, specificity, and odds ratio of the cut-off value were 0.4, 0.9, and 4.8 for the MLA ratio, and 0.6, 0.7, and 9.8 for the diff-TAL, respectively. Decreased flexibility of the transverse arch and decreased MLA ratio are risk factors for MTSS. In contrast, the flexibility of the MLA and the height of the transverse arch were not risk factors for MTSS.

  12. Medial pivot knee in primary total knee arthroplasty.

    PubMed

    Atzori, Francesco; Salama, Wael; Sabatini, Luigi; Mousa, Shazly; Khalefa, Abdelrahman

    2016-01-01

    Total knee arthroplasty (TKA) with a medial pivot design was developed in order to mimic normal knee kinematics; the highly congruent medial compartment implant should improve clinical results and decrease contact stresses. Clinical and radiographic mid-term outcomes are satisfactory, but we need other studies to evaluate long-term results and indications for unusual cases.

  13. Medial patellofemoral ligament and medial patellotibial ligament reconstruction in children: preliminary results.

    PubMed

    Sadigursky, David; Garcia, Lucas Cortizo; Armede, Maurício; Oliveira, Lucas Rodrigues de; Carneiro, Rogério Jamil Fernandes; Colavolpe, Paulo Oliveira

    2017-01-01

    The aim of this study was to evaluate the reconstruction of the medial patellofemoral ligament associated with the medial patellotibial ligament in skeletally immature patients. This is a case series study in patients with patellar instability with open physis. In total, seven patients were evaluated: four males and three females were operated using the proposed technique. Patients with open physis who had more than two episodes of recurring patellar dislocation were included. No patients underwent additional procedures. The distance from the anterior tibial tuberosity to the trochlea grove (TT-TG) was measured in all patients. On physical examination, the inverted J-sign, the apprehension sign, and the knee range of motion parameters were used in the pre- and post-operative period. In addition, the Kujala and Lysholm scores were applied before and 12 months after surgery. The results were analyzed with the Wilcoxon test. The mean age of the patients was 11.28 in both genders. Comparing the data of the pre- and post-operative period, the inverted J-sign was present in six patients (85.7%) vs. absent in one (14.3%). The apprehension sign was absent in cases in the postoperative period; the range of motion was 117.85 ± 8.09 vs. 148.57 ± 3.77. The Kujala score was 42.57 ± 8.9 vs. 88.57 ± 5.09 and the Lysholm scores were classified as excellent or good in 28.6% and 71.4%, respectively. The combined reconstruction of the medial patellofemoral ligament combined with the medial patellotibial ligament in skeletally immature patients with predisposing factors, presents satisfactory results without episodes of recurrence or residual subluxation; according to these preliminary results, it should be considered as a treatment option.

  14. Basket-Weave Technique for Medial Patellofemoral Ligament Reconstruction

    PubMed Central

    Kodkani, Pranjal S.

    2015-01-01

    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

  15. Superficial radial sensory neuropathy: Medial and lateral branch injury.

    PubMed

    Cho, Nam Soon; Kim, Ki Hoon; Park, Byung Kyu; Kim, Dong Hwee

    2016-05-01

    Superficial radial sensory nerve (SRN) injury may involve the main nerve or its distal medial or lateral branch. We investigated the utility of SRN conduction studies on the medial and lateral branches in patients with suspected SRN injury. Fifteen patients with symptoms of SRN neuropathy were studied. Their clinical and electrophysiological findings were assessed according to sensory symptom areas. Three active recording electrode positions were used: snuff box (position A); medial branch (position B); and lateral branch (position C). In 7 patients with medial area symptoms, abnormal findings were seen in position B (100%) and position A (71%). In 3 patients with medial and lateral area symptoms, abnormal findings were seen in all positions. In 5 patients with lateral symptoms, abnormal findings were seen in position C only. Nerve conduction studies for each branch of the SRN are useful in patients with suspected SRN neuropathy. © 2016 Wiley Periodicals, Inc.

  16. The origin and distribution of CD68, CD163, and αSMA(+) cells in the early phase after meniscal resection in a parabiotic rat model.

    PubMed

    Terai, Shozaburo; Hashimoto, Yusuke; Orita, Kumi; Yamasaki, Shinya; Takigami, Junsei; Shinkuma, Takafumi; Teraoka, Takanori; Nishida, Yohei; Takahashi, Masafumi; Nakamura, Hiroaki

    2017-02-06

    We previously reported that circulating peripheral blood-borne cells (PBCs) contribute to early-phase meniscal reparative change. Because macrophages and myofibroblasts are important contributors of tissue regeneration, we examined their origin and distribution in the reparative meniscus. Reparative menisci were evaluated at 1, 2, and 4 weeks post-meniscectomy by immunohistochemistry to locate monocytes and macrophages (stained positive for CD68 and CD163), and myofibroblasts (stained positive for αSMA). Of the total number of cells, 13% were CD68(+) at 1 week post-meniscectomy, which decreased to 1% by 4 weeks post-meniscectomy; of these, almost half of CD68(+) cells (49.4%: 98.8% as PBCs) were green fluorescent protein (GFP)-positive post-meniscectomy (1, 2, and 4 weeks), indicating that the majority of CD68(+) cells were derived from PBCs. Of the total cells, 6% were CD163(+) at 1 week post-meniscectomy, which decreased to 1% by week 4. Of the CD163(+) cells, the majority were GFP-positive (42.5%: 85.0% as PBCs) after 1 week; however, this decreased significantly over time, which indicates that the majority of CD163(+) cells are derived from PBCs during the early phase of meniscal reparative change, but are derived from resident cells at later time points. Of the total cells, 38% were αSMA(+) at 1 week post-meniscectomy, which decreased to 3% by 4 weeks. The proportion of GFP-positive αSMA(+) cells was 2.8% after 1 week, with no significant change over time, which indicates that the majority of αSMA(+) cells originated from resident cells. Here, we describe the origin and distribution of macrophages and myofibroblasts during meniscal reparative change.

  17. Fear Expression Suppresses Medial Prefrontal Cortical Firing in Rats

    PubMed Central

    Giustino, Thomas F.; Fitzgerald, Paul J.; Maren, Stephen

    2016-01-01

    The medial prefrontal cortex (mPFC) plays a crucial role in emotional learning and memory in rodents and humans. While many studies suggest a differential role for the prelimbic (PL) and infralimbic (IL) subdivisions of mPFC, few have considered the relationship between neural activity in these two brain regions recorded simultaneously in behaving animals. Importantly, how concurrent PL and IL activity relate to conditioned freezing behavior is largely unknown. Here we used single-unit recordings targeting PL and IL in awake, behaving rats during the acquisition and expression of conditioned fear. On Day 1, rats received either signaled or unsignaled footshocks in the recording chamber; an auditory conditioned stimulus (CS) preceded signaled footshocks. Twenty-four hours later, animals were returned to the recording chamber (modified to create a novel context) where they received 5 CS-alone trials. After fear conditioning, both signaled and unsignaled rats exhibited high levels of post-shock freezing that was associated with an enduring suppression of mPFC spontaneous firing, particularly in the IL of signaled rats. Twenty-four hours later, CS presentation produced differential conditioned freezing in signaled and unsignaled rats: freezing increased in rats that had received signaled shocks, but decreased in animals in the unsignaled condition (i.e., external inhibition). This group difference in CS-evoked freezing was mirrored in the spontaneous firing rate of neurons in both PL and IL. Interestingly, differences in PL and IL firing rate highly correlated with freezing levels. In other words, in the signaled group IL spontaneous rates were suppressed relative to PL, perhaps limiting IL-mediated suppression of fear and allowing PL activity to dominate performance, resulting in high levels of freezing. This was not observed in the unsignaled group, which exhibited low freezing. These data reveal that the activity of mPFC neurons is modulated by both associative and

  18. Comparison of growth factor treatments on the fibrochondrogenic potential of canine fibroblast-like synoviocytes for meniscal tissue engineering.

    PubMed

    Spina, Jason; Warnock, Jennifer; Duesterdieck-Zellmer, Katja; Baltzer, Wendy; Ott, Jesse; Bay, Brian

    2014-08-01

    To determine the in vitro effects of differing growth factor treatments on the fibrochondrogenic potential of fibroblast-like synoviocytes from cruciate ligament deficient femorotibial joints of dogs. In vitro study. Synoviocytes from dogs (n = 8) with naturally occurring cruciate ligament insufficiency. Synoviocytes were cultured in monolayer and synthesized into tensioned synoviocyte bioscaffolds (TSB) suspended in media containing TGF-β3, or FGF-2, TGF-β1, and IGF-I. The 1,9-dimethylmethylene blue (DMMB) assay and toluidine blue stain assessed glycosaminoglycan content; hydroxyproline assay, and collagen I and II immunohistochemistry assessed collagen content. Biomechanical properties were determined by materials testing/force-deformation curves. All tissue cultures formed tensioned fibrous tissue-like constructs. Mean tissue cellularity and cellular viability was significantly greater in the triple growth factor-treated TSB by 0.09% and 44%, respectively. Percentage collagen content, and relative gene expression for collagen I, II, and aggrecan was not significantly different between groups. Median percentage of GAG content was significantly greater in triple growth factor-treated TSB by 1.6%. Biomechanical properties were not different in compression. Triple growth factor-treated TSB were significantly stronger in toughness, peak load to failure, and stiffness in tension. TGF-β3 cultured bioscaffolds failed to outperform triple growth factor-treated TSB. Architectural extracellular matrix (ECM) organization and cellularity likely explained the differences between groups. TGF-β3 alone cannot be recommended at this time for in vitro formation of autologous fibrocartilage bioscaffolds for meniscal deficiency. © Copyright 2014 by The American College of Veterinary Surgeons.

  19. 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.

  20. 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.

  1. Medial capsule reefing in patellar instability.

    PubMed

    Cerciello, Simone; Vasso, Michele; Corona, Katia; Del Regno, Chiara; Panni, Alfredo Schiavone

    2014-10-01

    The efficacy of medial capsule reefing in the treatment of patellar instability is well documented. Aim of the present study was to prospectively evaluate the outcomes of an all-arthroscopic medial capsule reefing technique in young patients with painful patella syndrome and potential patellar instability. Thirty patients with painful patellar syndrome and potential patellar instability having undergone a minimum of 6 months of intensive rehabilitation were enrolled in the present study. All subjects were evaluated with physical examination, clinical and functional outcomes and complete imaging study. All patients were reviewed at an intermediate follow-up of 72 months. Average Kujala score improved from 72.9±15.0 to 88.4±7.6 (p<0.0001), average Larsen score from 15.0±2.5 to 17.2±2.2 (p<0.002), average Lysholm from 63.8±16.7 to 87.9±11.7 (p<0.0001) and average Fulkerson score from 69.5±21.5 to 90.8±9.8 (p<0.0001). No intraoperative or postoperative complications were recorded. Ninety per cent of patients were very satisfied or satisfied with their functional result. Twenty-eight patients were reviewed at the final follow-up, 120 months after surgery. Average Kujala was 87.7±8.8 (p<0.0001), average Larsen was 16.8±2.7 (p<0.01), average Lysholm was 87.6±14.3 (p<0.0001), and average Fulkerson was 87.2±13.9 (p<0.0001). Almost 86% of patients were very satisfied or satisfied with their result. However, slight deterioration of the outcomes over time was observed. At the final follow-up, the outcomes of all-arthroscopic technique were significantly improved from preoperative values; however, they were slightly inferior at the 72 months follow-up. This slight deterioration of the outcomes may be the consequence of the reduction in physical activities. Case series, Level IV.

  2. [Constraints on the knee caused by meniscal and ligament derangement. Study of the internal condylotibial joint. Experimental cinematic method].

    PubMed

    Frain, P; Fontaine, C; D'Hondt, D

    1984-01-01

    In a previous paper the authors have demonstrated that the polycentric curve of the surface of the medial condyle of the femur is a logarithmic spiral arch whose centre is the point of attachment of the medial ligament. In the present study, the totality of the menisco-ligamentous system was considered and studied on cadavers following a geometric model. It is shown that the ligament system controls combined or successive movements of gliding or rotation of the condyle on the tibial plateau in such a way as to avoid any cam effect or additional strain. Division of ligaments or excision of a meniscus leads to an increase in strain which varies in relation to the type of lesion. The increase is moderate after division of the anterior cruciate ligament, greater after division of the posterior cruciate ligament and severe after meniscectomy especially when associated with ligamentous division.

  3. The medial scaffold of 3D unorganized point clouds.

    PubMed

    Leymarie, Frederic F; Kimia, Benjamin B

    2007-02-01

    We introduce the notion of the medial scaffold, a hierarchical organization of the medial axis of a 3D shape in the form of a graph constructed from special medial curves connecting special medial points. A key advantage of the scaffold is that it captures the qualitative aspects of shape in a hierarchical and tightly condensed representation. We propose an efficient and exact method for computing the medial scaffold based on a notion of propagation along the scaffold itself, starting from initial sources of the flow and constructing the scaffold during the propagation. We examine this method specifically in the context of an unorganized cloud of points in 3D, e.g., as obtained from laser range finders, which typically involve hundreds of thousands of points, but the ideas are generalizable to data arising from geometrically described surface patches. The computational bottleneck in the propagation-based scheme is in finding the initial sources of the flow. We thus present several ideas to avoid the unnecessary consideration of pairs of points which cannot possibly form a medial point source, such as the "visibility" of a point from another given a third point and the interaction of clusters of points. An application of using the medial scaffold for the representation of point samplings of real-life objects is also illustrated.

  4. Molecular mechanisms in the formation of the medial longitudinal fascicle

    PubMed Central

    Ahsan, Mansoor; Riley, Kerry-lyn; Schubert, Frank R

    2007-01-01

    The first neurons in the vertebrate brain form a stereotypical array of longitudinal and transversal axon tracts, the early axon scaffold. This scaffold is thought to lay down the basic structure for the later, more complex neuronal pathways in the brain. The ventral longitudinal tract is pioneered by neurons located at the ventral midbrain–forebrain boundary, which form the medial longitudinal fascicle. Recent studies have shed some light on the molecular mechanisms that control the development of the medial longitudinal fascicle. Here, we show that patterning molecules, notably the ventralizing signalling molecule Shh, are involved in the formation of medial longitudinal fascicle neurons and in medial longitudinal fascicle axon guidance. Downstream of Shh, several homeobox genes are expressed in the tegmentum. We describe the expression patterns of Sax1, Emx2, Six3, Nkx2.2 and Pax6 in the mesencephalon and pretectum in detail. Furthermore, we review the evidence of their molecular interactions, and their involvement in neuronal fate specification. In particular, Sax1 plays a major role in fate determination of medial longitudinal fascicle neurons. Finally, we discuss the available data on axon guidance mechanisms for the medial longitudinal fascicle, which suggest that different guidance molecules such as class 3 Semaphorins, Slits and Netrins act to determine the caudal and ventral course of the medial longitudinal fascicle axons. PMID:17623036

  5. Chronic Phencyclidine Increases Synapsin-1 and Synaptic Adaptation Proteins in the Medial Prefrontal Cortex

    PubMed Central

    Pickering, Chris; Ericson, Mia; Söderpalm, Bo

    2013-01-01

    Phencyclidine (PCP) mimics many aspects of schizophrenia, yet the underlying mechanism of neurochemical adaptation for PCP is unknown. We therefore used proteomics to study changes in the medial prefrontal cortex in animals with PCP-induced behavioural deficits. Male Wistar rats were injected with saline or 5 mg/kg phencyclidine for 5 days followed by two days of washout. Spontaneous alternation behaviour was tested in a Y-maze and then proteins were extracted from the medial prefrontal cortex. 2D-DIGE analysis followed by spot picking and protein identification with mass spectrometry then provided a list of differentially expressed proteins. Treatment with 5 mg/kg phencyclidine decreased the percentage of correct alternations in the Y-maze compared to saline-treated controls. Proteomics analysis of the medial prefrontal cortex found upregulation of 6 proteins (synapsin-1, Dpysl3, Aco2, Fscn1, Tuba1c, and Mapk1) and downregulation of 11 (Bin1, Dpysl2, Sugt1, ApoE, Psme1, ERp29, Pgam1, Uchl1, Ndufv2, Pcmt1, and Vdac1). A trend to upregulation was observed for Gnb4 and Capza2, while downregulation trends were noted for alpha-enolase and Fh. Many of the hits in this study concur with recent postmortem data from schizophrenic patients and this further validates the use of phencyclidine in preclinical translational research. PMID:23738220

  6. 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.

  7. Development of the medial hypothalamus: forming a functional hypothalamic-neurohypophyseal interface.

    PubMed

    Pearson, Caroline Alayne; Placzek, Marysia

    2013-01-01

    The medial hypothalamus is composed of nuclei of the tuberal hypothalamus, the paraventricular nucleus of the anterior hypothalamus, and the neurohypophysis. Its arrangement, around the third ventricle of the brain, above the adenohypophysis, and in direct contact with the vasculature, means that it serves as an interface with circulating systems, providing a key conduit through which the brain can sample, and control, peripheral body systems. Through these interfaces, and interactions with other parts of the brain, the medial hypothalamus centrally governs diverse homeostatic processes, including energy and fluid balance, stress responses, growth, and reproductive behaviors. Here, we summarize recent studies that reveal how the diverse cell types within the medial hypothalamus are assembled in an integrated manner to enable its later function. In particular, we discuss how the temporally protracted operation of signaling pathways and transcription factors governs the appearance and regionalization of the hypothalamic primordium from the prosencephalic territory, the specification and differentiation of progenitors into neurons in organized nuclei, and the establishment of interfaces. Through analyses of mouse, chick, and zebrafish, a picture emerges of an evolutionarily conserved and highly coordinated developmental program. Early indications suggest that deregulation of this program may underlie complex human pathological conditions and dysfunctional behaviors, including stress and eating disorders. © 2013 Elsevier Inc. All rights reserved.

  8. 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.

  9. Medial olivocochlear reflex in ankylosing spondylitis patients.

    PubMed

    Beyazal, M S; Özgür, A; Terzi, S; Çeliker, M; Dursun, E

    2016-12-01

    Ankylosing spondylitis (AS) is a chronic systemic inflammatory disease. Via autoimmune mediators, AS can damage the auditory system similar to other systems. Otoacoustic emission studies in AS patients showed that the damage that causes hearing loss was in the outer hair cells. The medial olivocochlear (MOC) reflex is used to evaluate the MOC efferent system (MOES), which includes the outer hair cells. The aim of this study was to evaluate the presence of subclinical damage in the inner ear with the aid of the MOC reflex test in AS patients with no hearing complaints. Thirty-four patients with AS and a control group of 30 healthy volunteers with similar demographic characteristics were evaluated in the study. Otoacoustic emission responses, MOC reflex results, and frequency-specific and total suppression findings were compared between the groups. The relationship between clinical and laboratory findings for the AS patients, and the MOC reflex data were also investigated. Reduced MOC reflex response (p = 0.04) and suppression (p = 0.019) were detected in AS patients. When the clinical and laboratory findings for the AS patients and the MOC reflex test results were compared, a significant correlation was found only between the MOC reflex and the erythrocyte sedimentation rate. The results showed that AS can damage the inner ear, especially the MOES, and can reduce the MOC reflex response without clinical hearing loss.

  10. Chronic medial instability of the elbow.

    PubMed

    Savoie, Felix H; O'Brien, Michael

    2017-01-01

    Damage to the medial collateral ligament of the elbow from an instability episode usually heals with non-operative treatment. In some cases, residual instability may occur, leading to functional impairment.Non-operative management can be successful when bracing, taping and therapy are used to stabilise the elbow.A recent report detailing the efficacy of platelet-rich plasma in effectively treating ulnar collateral ligament (UCL) injuries in throwers has shown promise. However, there remain specific groups that should be considered for repair or reconstruction. These may include throwing athletes, wrestlers and some individuals involved in highly active physical activity which demands stability of the elbow.The results of surgical repair and reconstruction allowing a return to sports are quite good, ranging from 84% to 94%. Complications are generally low and mostly centred on ulnar nerve injuries.This report represents a review of the literature concerning valgus instability over the past five years, supplemented by selective older articles where relevant. Cite this article: EFORT Open Rev 2017;2:1-6. DOI:10.1302/2058-5241.2.160037.

  11. 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

  12. 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

  13. Subspecialization in the human posterior medial cortex.

    PubMed

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

    2015-02-01

    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-unconstrained but not task-constrained connectivity. We thus identified distinct regions in the PMC and characterized their neural networks and functional implications. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Medial subclavicular musculotendinous complex and insulation break: Rare cause of late pacemaker lead malfunction

    PubMed Central

    Bhattacharyya, Pranab Jyoti; Agrawal, Shweta; Barkataky, Jogesh Chandra; Bhattacharyya, Anjan Kumar

    2015-01-01

    Insulation break in a permanent pacemaker lead is a rare long-term complication. We describe an elderly male with a VVIR pacemaker, who presented with an episode of presyncope more than 3 years after the initial implantation procedure, attributed to insulation break possibly caused by lead entrapment in components of the medial subclavicular musculotendinous complex (MSMC) and repeated compressive damage over time during ipsilateral arm movement requiring lead replacement. The differential diagnosis of a clinical presentation when pacing stimuli are present with failure to capture and the role of the MSMC in causing lead damage late after implantation are discussed. PMID:26995445

  15. Microanatomy of the medial collateral ligament enthesis in the bovine knee.

    PubMed

    Thambyah, Ashvin; Lei, Zhao; Broom, Neil

    2014-12-01

    This study applied transmission and differential interference contrast light microscopy imaging methodologies to revisit the microanatomy of the ligament-bone junction of the medial collateral ligament, with the aim of providing new insights into the mechanostructural significance of the enthesis. The data show that the microscale structural features of the enthesis are more complex than the conventional description of "direct versus indirect," or "fibrous versus nonfibrous" insertions. From a materials perspective the enthesis may be viewed as a specialised functionally graded structural continuum whose unique microlevel structural adaptation contributes to maintaining both the local tissue micromechanical environment and joint function at the macrolevel. © 2014 Wiley Periodicals, Inc.

  16. Confocal arthroscopy-based patient-specific constitutive models of cartilaginous tissues - II: prediction of reaction force history of meniscal cartilage specimens.

    PubMed

    Taylor, Zeike A; Kirk, Thomas B; Miller, Karol

    2007-10-01

    The theoretical framework developed in a companion paper (Part I) is used to derive estimates of mechanical response of two meniscal cartilage specimens. The previously developed framework consisted of a constitutive model capable of incorporating confocal image-derived tissue microstructural data. In the present paper (Part II) fibre and matrix constitutive parameters are first estimated from mechanical testing of a batch of specimens similar to, but independent from those under consideration. Image analysis techniques which allow estimation of tissue microstructural parameters form confocal images are presented. The constitutive model and image-derived structural parameters are then used to predict the reaction force history of the two meniscal specimens subjected to partially confined compression. The predictions are made on the basis of the specimens' individual structural condition as assessed by confocal microscopy and involve no tuning of material parameters. Although the model does not reproduce all features of the experimental curves, as an unfitted estimate of mechanical response the prediction is quite accurate. In light of the obtained results it is judged that more general non-invasive estimation of tissue mechanical properties is possible using the developed framework.

  17. 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. Copyright © 2016. Published by Elsevier Inc.

  18. Medial temporal lobe and topographical memory.

    PubMed

    Urgolites, Zhisen J; Hopkins, Ramona O; Squire, Larry R

    2017-08-08

    There has been interest in the idea that medial temporal lobe (MTL) structures might be especially important for spatial processing and spatial memory. We tested the proposal that the MTL has a specific role in topographical memory as assessed in tasks of scene memory where the viewpoint shifts from study to test. Building on materials used previously for such studies, we administered three different tasks in a total of nine conditions. Participants studied a scene depicting four hills of different shapes and sizes and made a choice among four test images. In the Rotation task, the correct choice depicted the study scene from a shifted perspective. MTL patients succeeded when the study and test images were presented together but failed the moment the study scene was removed (even at a 0-s delay). In the No-Rotation task, the correct choice was a duplicate of the study scene. Patients were impaired to the same extent in the No-Rotation and Rotation tasks after matching for difficulty. Thus, an inability to accommodate changes in viewpoint does not account for patient impairment. In the Nonspatial-Perceptual task, the correct choice depicted the same overall coloring as the study scene. Patients were intact at a 2-s delay but failed at longer, distraction-filled delays. The different results for the spatial and nonspatial tasks are discussed in terms of differences in demand on working memory. We suggest that the difficulty of the spatial tasks rests on the neocortex and on the limitations of working memory, not on the MTL.

  19. Unloader Braces for Medial Compartment Knee Osteoarthritis

    PubMed Central

    Ramsey, Dan K.; Russell, Mary E.

    2009-01-01

    Background: For persons with unicompartment knee osteoarthritis (OA), off-unloader braces are a mechanical intervention designed to reduce pain, improve physical function, and possibly slow disease progression. Pain relief is thought to be mediated by distracting the involved compartment via external varus or valgus forces applied to the knee. In so doing, tibiofemoral alignment is improved, and load is shifted off the degenerative compartment, where exposure to potentially damaging and provocative mechanical stresses are reduced. Objectives: To provide a synopsis of the evidence documented in the scientific literature concerning the efficacy of off-loader knee braces for improving symptomatology associated with painful disabling medial compartment knee OA. Search Strategy: Relevant peer-reviewed publications were retrieved from a MEDLINE search using the terms with the reference terms osteoarthritis, knee, and braces (per Medical Subject Headings), plus a manual search of bibliographies from original and review articles and appropriate Internet resources. Results: For persons with combined unicompartment knee OA and mild to moderate instability, the strength of recommendation reported by the Osteoarthritis Research Society International in the ability of off-loader knee braces to reduce pain, improve stability, and diminish the risk of falling was 76% (95% confidence interval, 69%-83%). The more evidence the treatment is effective, the higher the percentage. Conclusions: Given the encouraging evidence that off-loader braces are effective in mediating pain relief in conjunction with knee OA and malalignment, bracing should be fully used before joint realignment or replacement surgery is considered. With the number of patients with varus deformities and knee pain predicted to increase as the population ages, a reduction of patient morbidity for this widespread chronic condition in combination with this treatment modality could have a positive impact on health care

  20. Medial tibial stress syndrome: a critical review.

    PubMed

    Moen, Maarten H; Tol, Johannes L; Weir, Adam; Steunebrink, Miriam; De Winter, Theodorus C

    2009-01-01

    Medial tibial stress syndrome (MTSS) is one of the most common leg injuries in athletes and soldiers. The incidence of MTSS is reported as being between 4% and 35% in military personnel and athletes. The name given to this condition refers to pain on the posteromedial tibial border during exercise, with pain on palpation of the tibia over a length of at least 5 cm. Histological studies fail to provide evidence that MTSS is caused by periostitis as a result of traction. It is caused by bony resorption that outpaces bone formation of the tibial cortex. Evidence for this overloaded adaptation of the cortex is found in several studies describing MTSS findings on bone scan, magnetic resonance imaging (MRI), high-resolution computed tomography (CT) scan and dual energy x-ray absorptiometry. The diagnosis is made based on physical examination, although only one study has been conducted on this subject. Additional imaging such as bone, CT and MRI scans has been well studied but is of limited value. The prevalence of abnormal findings in asymptomatic subjects means that results should be interpreted with caution. Excessive pronation of the foot while standing and female sex were found to be intrinsic risk factors in multiple prospective studies. Other intrinsic risk factors found in single prospective studies are higher body mass index, greater internal and external ranges of hip motion, and calf girth. Previous history of MTSS was shown to be an extrinsic risk factor. The treatment of MTSS has been examined in three randomized controlled studies. In these studies rest is equal to any intervention. The use of neoprene or semi-rigid orthotics may help prevent MTSS, as evidenced by two large prospective studies.

  1. Anterior cruciate ligament and medial collateral ligament injuries.

    PubMed

    Bollier, Matthew; Smith, Patrick A

    2014-10-01

    The diagnosis and treatment of combined anterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries have evolved over the past 30 years. A detailed physical examination along with careful review of the magnetic resonance imaging and stress radiographs will guide decision making. Early ACL reconstruction and acute MCL repair are recommended when there is increased medial joint space opening with valgus stress in extension, a significant meniscotibial deep MCL injury (high-riding medial meniscus), or a displaced tibial-sided superficial MCL avulsion (stener lesion of the knee). Delayed ACL reconstruction to allow for MCL healing is advised when increased valgus laxity is present only at 30 degrees of flexion and not at 0 degree. However, at the time of ACL surgery, medial stability has to be re-assessed after the reconstruction is completed. In patients with neutral alignment in the chronic setting, graft reconstruction of both the ACL and MCL is recommended.

  2. Evaluation of the medial elbow in the throwing athlete.

    PubMed

    Creighton, R Alexander; Bach, Bernard R; Bush-Joseph, Charles A

    2006-06-01

    The valgus forces generated by throwing athletes can cause injuries and permanently damage the medial elbow structures. Clinicians must have a clear understanding of the ulnar collateral ligament complex and the associated medial elbow structures at risk in these athletes. Taking a detailed history, conducting a physical examination, and obtaining imaging studies will aid in making the correct diagnosis and giving these injuries the appropriate treatment. Pain around the medial elbow is of concern to throwing athletes, coaches, and medical staff. Valgus forces generated by the throwing motion add considerable stress to the medial elbow structures and thus potentially cause injury. Baseball players, particularly pitchers, are most often affected, but athletes participating in sports such as football, volleyball, water polo, tennis, and javelin throwing can also be affected.

  3. 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

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

    PubMed Central

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

    2014-01-01

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

  5. GABAergic projections from the medial septum selectively inhibit interneurons in the medial entorhinal cortex.

    PubMed

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

    2014-12-10

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

  6. Medial entorhinal cortex and medial septum contribute to self-motion-based linear distance estimation.

    PubMed

    Jacob, Pierre-Yves; Gordillo-Salas, Marta; Facchini, Justine; Poucet, Bruno; Save, Etienne; Sargolini, Francesca

    2017-02-04

    Path integration is a navigation strategy that requires animals to integrate self-movements during exploration to determine their position in space. The medial entorhinal cortex (MEC) has been suggested to play a pivotal role in this process. Grid cells, head-direction cells, border cells as well as speed cells within the MEC collectively provide a dynamic representation of the animal position in space based on the integration of self-movements. All these cells are strongly modulated by theta oscillations, thus suggesting that theta rhythmicity in the MEC may be essential for integrating and coordinating self-movement information during navigation. In this study, we first show that excitotoxic MEC lesions, but not dorsal hippocampal lesions, impair the ability of rats to estimate linear distances based on self-movement information. Next, we report similar deficits following medial septum inactivation, which strongly impairs theta oscillations in the entorhinal-hippocampal circuits. Taken together, these findings demonstrate a major role of the MEC and MS in estimating distances to be traveled, and point to theta oscillations within the MEC as a neural mechanism responsible for the integration of information generated by linear self-displacements.

  7. The perforator-based conjoint (chimeric) medial Sural(MEDIAL GASTROCNEMIUS) free flap.

    PubMed

    Sano, Kazufumi; Hallock, Geoffrey G; Hamazaki, Masahiro; Daicyo, Yoshihiro

    2004-12-01

    The prototypical conjoint or so-called "chimeric" free flap heretofore has been composed of several large independent flaps, each supplied by a separate major branch, that ultimately arise from a common source vessel. The perforator-based type of chimeric flap is a relatively new concept, usually involving multiple muscle perforator flaps each based on a solitary musculocutaneous perforator, but still arising from the same "mother" vessel. This principle of split cutaneous perforator flaps has been now successfully adapted to the medial suralMEDIAL GASTROCNEMIUS perforator free flap on 2 separate occasions. As a chimeric flap, there was greater flexibility in insetting, and overall flap width may be larger but still narrow enough to allow primary donor site closure; and yet, by definition, only a single recipient site was needed for any microanastomoses. This is further proof that the perforator-based chimeric free flap may be an option for any muscle perforator flap donor site, so that potential donor territories for conjoint flaps have become virtually unlimited.

  8. Medial rectus muscle anchoring in complete oculomotor nerve palsy.

    PubMed

    Lee, Si Hyung; Chang, Jee Ho

    2015-10-01

    The management of exotropia resulting from complete oculomotor nerve palsy is challenging. Conventional therapeutic interventions, including supramaximal resection and recession, superior oblique tendon resection and transposition, and several ocular anchoring procedures have yielded less-than-adequate results. Here we describe a novel surgical technique of anchoring the medial rectus muscle to the medial orbital wall in combination with lateral rectus disinsertion and reattachment to the lateral orbital wall.

  9. 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

  10. Why Do Authors Differ With Regard to the Femoral and Meniscal Anatomic Parameters of the Knee Anterolateral Ligament?

    PubMed Central

    Helito, Camilo Partezani; do Amaral, Carlos; Nakamichi, Yuri da Cunha; Gobbi, Riccardo Gomes; Bonadio, Marcelo Batista; Natalino, Renato José Mendonça; Pécora, José Ricardo; Cardoso, Tulio Pereira; Camanho, Gilberto Luis; Demange, Marco Kawamura

    2016-01-01

    Background: No consensus exists regarding the anatomic characteristics of the knee anterolateral ligament (ALL). A critical analysis of the dissections described in previous studies allows the division of the ALL into 2 groups with similar characteristics. The presence of considerable variability suggests that the authors may not be referring to the same structure. Purpose/Hypothesis: To perform a lateral anatomic dissection, by layers, seeking to characterize the 2 variants described for the ALL on the same knee. We hypothesized that we would identify the 2 variants described for the ALL and that these variants would have distinct characteristics. Study Design: Descriptive laboratory study. Methods: Thirteen unpaired cadaveric knees were used in this study. The dissection protocol followed the parameters described in previous studies. Immediately below the iliotibial tract, we isolated a structure designated as the superficial ALL, whereas between this structure and the articular capsule, we isolated a structure designated as the deep ALL. The 2 structures were measured for length at full extension and at 90° of flexion and for distance from the tibial insertion relative to the Gerdy tubercle. Potential contact with the lateral meniscus was also evaluated. After measurements were obtained, the 2 dissected structures underwent histologic analysis. Results: The superficial ALL presented a posterior and proximal origin to the center of the lateral epicondyle, its length increased on knee extension, and it exhibited no contact with the lateral meniscus. The deep ALL was located in the center of the lateral epicondyle, its length increased on knee flexion, and it presented a meniscal insertion. Both structures had a similar tibial insertion site; however, the insertion site of the deep ALL was located more posteriorly. The analysis of the histological sections for both structures indicated the presence of dense and well-organized collagen fibers. Conclusion: This

  11. Symptomatic Accessory Medial Meniscus Associated With Popliteal Pterygium Syndrome.

    PubMed

    Funk, Shawn S; Block, J Jake; Martus, Jeffrey E; Schoenecker, Jonathan G

    2015-01-01

    Anomalies of the meniscus are uncommon. These anomalous formations have been predominately described in the lateral compartment of the knee. Congenital abnormalities of the medial meniscus are rare. Chart and radiographic review of a single patient with a symptomatic congenital abnormality of the medial meniscus. The patient was a 5-year-old boy with popliteal pterygium who developed painful snapping in the medial knee after anterior hemiepiphyseodesis to improve his knee extension. The patient had achieved full-knee extension from a preoperative 45-degree flexion contracture. The newly developed snapping was attributed to the hemiepiphyseodesis implants. After implant removal, the snapping persisted and was localized at the medial joint line. Through an arthrotomy, a medial meniscus abnormality was identified and excised with resolution of symptoms. This report describes a symptomatic congenital abnormality of the medial meniscus in a child with popliteal pterygium. The patient was treated with excision of the anomalous structure with complete resolution of the symptoms. This is the first report of an intra-articular knee anomaly associated with popliteal pterygium syndrome.

  12. Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards (Uta stansburiana).

    PubMed

    LaDage, Lara D; Roth, Timothy C; Downs, Cynthia J; Sinervo, Barry; Pravosudov, Vladimir V

    2017-01-01

    Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial-defending large, clearly defined spatial boundaries-or non-territorial-traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer doublecortin

  13. Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards (Uta stansburiana)

    PubMed Central

    LaDage, Lara D.; Roth, Timothy C.; Downs, Cynthia J.; Sinervo, Barry; Pravosudov, Vladimir V.

    2017-01-01

    Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial—defending large, clearly defined spatial boundaries—or non-territorial—traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer

  14. An anatomical measurement of medial femoral torsion.

    PubMed

    Kim, Ha Y; Lee, Sang K; Lee, Neung K; Choy, Won S

    2012-11-01

    Medial femoral torsion (MFT) can be corrected with derotational osteotomy. Derotational osteotomies can be performed in the proximal or the distal part of the femur. Similar results have been reported for these two procedures. The aim of this study was to evaluate the pathologic location of the MFT by measuring the degree of infratrochanteric and supratrochanteric torsion (STT) of the femur using computed tomography (CT) scans. The current study was carried out in patients with the chief complaint of an in-toeing gait because of the MFT. Sixty-seven patients were enrolled in the study. Forty-one patients (72 lower extremities) were included in the intervention group; 20 patients were included in the cerebral palsy (CP) group (35 lower extremities) and 21 patients were included in the developmental MFT group [developmental femoral torsional (DF) group, 37 lower extremities]. The control group included 26 patients (33 lower extremities) with uninjured limbs with a femoral or a tibial fracture. In this study, torsional angles [MFT, STT and infratrochanteric torsion (ITT)] were measured on CT scan using picture archiving and communication system measurement tools. To measure the STT and ITT, the most prominent points of the lesser and the greater trochanter were marked on CT scans; these two points were connected and were defined as the intertrochanteric line (ITL). The angle between the ITL and the axis of the femoral neck was defined as the STT. The angle between the ITL and the axis of the condylar axis was defined as the ITT. Two authors measured the MFT, STT, and ITT angles of each femur independently. The twisting of the femur had occurred in a different location for each case. In all groups, however, STT was reduced with increasing age; this change was statistically significantly. ITT of the each group showed a random distribution. The means of the ITT in the control group and the DF group did not change significantly, and that of the CP group tended to decrease

  15. Medial Patellofemoral Ligament Reconstruction Femoral Tunnel Accuracy

    PubMed Central

    Hiemstra, Laurie A.; Kerslake, Sarah; Lafave, Mark

    2017-01-01

    Background: Medial patellofemoral ligament (MPFL) reconstruction is a procedure aimed to reestablish the checkrein to lateral patellar translation in patients with symptomatic patellofemoral instability. Correct femoral tunnel position is thought to be crucial to successful MPFL reconstruction, but the accuracy of this statement in terms of patient outcomes has not been tested. Purpose: To assess the accuracy of femoral tunnel placement in an MPFL reconstruction cohort and to determine the correlation between tunnel accuracy and a validated disease-specific, patient-reported quality-of-life outcome measure. Study Design: Case series; Level of evidence, 4. Methods: Between June 2008 and February 2014, a total of 206 subjects underwent an MPFL reconstruction. Lateral radiographs were measured to determine the accuracy of the femoral tunnel by measuring the distance from the center of the femoral tunnel to the Schöttle point. Banff Patella Instability Instrument (BPII) scores were collected a mean 24 months postoperatively. Results: A total of 155 (79.5%) subjects had adequate postoperative lateral radiographs and complete BPII scores. The mean duration of follow-up (±SD) was 24.4 ± 8.2 months (range, 12-74 months). Measurement from the center of the femoral tunnel to the Schöttle point resulted in 143 (92.3%) tunnels being categorized as “good” or “ideal.” There were 8 failures in the cohort, none of which occurred in malpositioned tunnels. The mean distance from the center of the MPFL tunnel to the center of the Schöttle point was 5.9 ± 4.2 mm (range, 0.5-25.9 mm). The mean postoperative BPII score was 65.2 ± 22.5 (range, 9.2-100). Pearson r correlation demonstrated no statistically significant relationship between accuracy of femoral tunnel position and BPII score (r = –0.08; 95% CI, –0.24 to 0.08). Conclusion: There was no evidence of a correlation between the accuracy of MPFL reconstruction femoral tunnel in relation to the Schöttle point and

  16. Rostral medial prefrontal dysfunctions and consummatory pleasure in schizophrenia: a meta-analysis of functional imaging studies.

    PubMed

    Yan, Chao; Yang, Tammy; Yu, Qi-Jing; Jin, Zhen; Cheung, Eric F C; Liu, Xun; Chan, Raymond C K

    2015-03-30

    A large number of imaging studies have examined the neural correlates of consummatory pleasure and anticipatory pleasure in schizophrenia, but the brain regions where schizophrenia patients consistently demonstrate dysfunctions remain unclear. We performed a series of meta-analyses on imaging studies to delineate the regions associated with consummatory and anticipatory pleasure dysfunctions in schizophrenia. Nineteen functional magnetic resonance imaging or positron emission tomography studies using whole brain analysis were identified through a literature search (PubMed and EBSCO; January 1990-February 2014). Activation likelihood estimation was performed using the GingerALE software. The clusters identified were obtained after controlling for the false discovery rate at p<0.05 and applying a minimum cluster size of 200 mm(3). It was found that schizophrenia patients exhibited decreased activation mainly in the rostral medial prefrontal cortex (rmPFC), the right parahippocampus/amygala, and other limbic regions (e.g., the subgenual anterior cingulate cortex, the putamen, and the medial globus pallidus) when consummating pleasure. Task instructions (feeling vs. stimuli) were differentially related to medial prefrontal dysfunction in schizophrenia. When patients anticipated pleasure, reduced activation in the left putamen was observed, despite the limited number of studies. Our findings suggest that the medial prefrontal cortex and limbic regions may play an important role in neural dysfunction underlying deficits in consummatory pleasure in schizophrenia.

  17. Predictors and Outcomes of Crossover to Surgery from Physical Therapy for Meniscal Tear and Osteoarthritis: A Randomized Trial Comparing Physical Therapy and Surgery.

    PubMed

    Katz, Jeffrey N; Wright, John; Spindler, Kurt P; Mandl, Lisa A; Safran-Norton, Clare E; Reinke, Emily K; Levy, Bruce A; Wright, Rick W; Jones, Morgan H; Martin, Scott D; Marx, Robert G; Losina, Elena

    2016-11-16

    Arthroscopic partial meniscectomy (APM) combined with physical therapy (PT) have yielded pain relief similar to that provided by PT alone in randomized trials of subjects with a degenerative meniscal tear. However, many patients randomized to PT received APM before assessment of the primary outcome. We sought to identify factors associated with crossing over to APM and to compare pain relief between patients who had crossed over to APM and those who had been randomized to APM. We used data from the MeTeOR (Meniscal Tear in Osteoarthritis Research) Trial of APM with PT versus PT alone in subjects ≥45 years old who had mild-to-moderate osteoarthritis and a degenerative meniscal tear. We assessed independent predictors of crossover to APM among those randomized to PT. We also compared pain relief at 6 months among those randomized to PT who crossed over to APM, those who did not cross over, and those originally randomized to APM. One hundred and sixty-four subjects were randomized to and received APM and 177 were randomized to PT, of whom 48 (27%) crossed over to receive APM in the first 140 days after randomization. In multivariate analyses, factors associated with a higher likelihood of crossing over to APM among those who had originally been randomized to PT included a baseline Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Score of ≥40 (risk ratio [RR] = 1.99; 95% confidence interval [CI] = 1.00, 3.93) and symptom duration of <1 year (RR = 1.74; 95% CI = 0.98, 3.08). Eighty-one percent of subjects who crossed over to APM and 82% of those randomized to APM had an improvement of ≥10 points in their pain score at 6 months, as did 73% of those who were randomized to and received only PT. Subjects who crossed over to APM had presented with a shorter symptom duration and greater baseline pain than those who did not cross over from PT. Subjects who crossed over had rates of surgical success similar to those of the patients who had been

  18. Evidence for a medial K+ recycling pathway from inner hair cells.

    PubMed

    Spicer, S S; Schulte, B A

    1998-04-01

    K+ effluxed from outer hair cells and their nerves is thought to flow laterally to strial marginal cells for recycling into scala media. Observations reported here provide evidence that K+ effluxed from inner hair cells and inner radial nerves travels medially through border cells, inner sulcus cells (ISCs), limbal fibrocytes and interdental cells (IDCs) for return to endolymph. Morphologic features of ISCs in the medial route resembled those of Hensen and Claudius cells in the lateral indicating an ion transport role for ISCs like that of Hensen and Claudius cells. Na,K-ATPase in plasmalemma of IDCs testified to their capacity to resorb and transport K+ through their known gap junctions. IDCs were differentiated into three subgroups. The most lateral IDCs formed short and long columns. Long columns contacted the medialmost ISC inferiorly and the undersurface of the tectorial membrane superiorly providing thereby a potential transcellular route for K+ transit from ISCs to endolymph. Short columns faced inner sulcus below and tectorial membrane above and accordingly possessed cells with opposite polarity at the bottom and top of the column. Short columns thus appeared situated to resorb electrolytes from limbal stroma for release into inner sulcus and beneath tectorial membrane at opposite ends of the column. The central IDCs were positioned for resorbing and transporting K+ effluxing from the Na,K-ATPase-rich stellate fibrocytes which spread toward the IDCs from near the inner sulcus. The most medial IDCs lined cuplike invaginations near the attachment of Reissner's membrane and lay apposed to light fibrocytes located between supralimbal fibrocytes and the medial IDCs. Content of Na,K-ATPase and position in the K+ transport route likened the limbal stellate fibrocytes to the spiral ligament type II fibrocytes and supralimbal fibrocytes to suprastrial fibrocytes in the lateral wall. From content of creatine kinase and position in the transport path, limbal light

  19. 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

  20. Contribution of the medial malleolus to tibiotalar joint contact characteristics.

    PubMed

    Lareau, Craig R; Bariteau, Jason T; Paller, David J; Koruprolu, Sarath C; DiGiovanni, Christopher W

    2015-02-01

    Isolated medial malleolus fractures are typically treated operatively to minimize the potential for articular incongruity, instability, nonunion, and posttraumatic arthritis. The literature, however, has not clearly demonstrated inferior outcomes with conservative treatment of these injuries. This study measured the effects of medial malleolus fracture and its resultant instability on tibiotalar joint contact characteristics. We hypothesized that restoration of anatomical alignment and stability through fixation would significantly improve contact characteristics. A Tekscan pressure sensor was inserted and centered over the talar dome in 8 cadaveric foot and ankle specimens. Each specimen was loaded at 700 N in multiple coronal and sagittal plane orientations. After testing fractured samples, the medial malleolus was anatomically fixed before repeat testing. Contact area and pressure were analyzed using a 2-way repeated-measure ANOVA. In treated fractures, contact areas were higher, and mean contact pressures were lower for all positions. These differences were statistically significant in the majority of orientations and approached statistical significance in pure plantarflexion and pure inversion. Decreases in contact area varied from 15.1% to 42.1%, with the most dramatic reductions in positions of hindfoot eversion. These data emphasize the importance of the medial malleolus in maintaining normal tibiotalar contact area and pressure. The average decrease in contact area after simulated medial malleolar fractures was 27.8% (>40% in positions of hindfoot eversion). Such differences become clinically relevant in cases of medial malleolar nonunion or malunion. Therefore, we recommend anatomical reduction and fixation of medial malleolus fractures with any displacement. Therapeutic Level V-Cadaveric Study. © 2014 The Author(s).

  1. 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

  2. Partial Meniscectomy Provides No Benefit for Symptomatic Degenerative Medial Meniscus Posterior Root Tears

    PubMed Central

    Krych, Aaron John; Johnson, Nick R.; Mohan, Rohith; Dahm, Diane L.; Levy, Bruce A.; Stuart, Michael J.

    2017-01-01

    Objectives: Medial meniscus posterior root tears (MMPRTs) are recognized as a source of pain and dysfunction, but treatment options remain a clinical challenge. Currently, outcomes are unknown following partial meniscectomy for these lesions. To determine (1) the efficacy of partial meniscectomy to treat MMPRTs compared to a matched group of non-operatively treated MMPRTs, and (2) risk factors for worse clinical and radiographic outcome. Methods: This retrospective comparative study was performed to include 27 patients with MMPRTs that were treated with arthroscopic partial meniscectomy (PMM) and a minimum 2-year follow-up. These patients were then matched by age, gender, and BMI to a group of 27 patients with MMPRTs treated non-operatively (control group). Demographic data, radiographic findings, final Tegner and IKDC scores were obtained and compared between the two groups. Risk factors for worse clinical and radiographic outcome in the PMM group alone, including age, sex, BMI, initial K-L grade, subchondral edema, and insufficiency fracture on MRI were determined. Results: Overall, 54 patients were included in the study. 27 patients (10M: 17F) with a mean age of 55±9 and a mean BMI of 32.8±5.3 were treated with PMM and followed for a mean of 5.5±2 years (range 2.3-9.3 years). In the PMM group, final median Tegner score was 3, mean IKDC scores were 67.8±20, median KL grades on weight-bearing AP films demonstrated progressive arthritis (median grade 1 to 2, p=0.001) and more patients had grade II or higher arthritis at final follow-up than baseline (91.3% vs. 36% p<0.01. Overall, 14 of the 27 patients (52%) treated operatively progressed to total knee arthroplasty at a mean of 54.3 months. When comparing the PMM and control groups, there was no significant difference in final median Tegner scores, mean IKDC, median K-L grades, progression to arthroplasty, or overall failure rate. Following PMM, female patients had lower final IKDC scores (74.6±16.7 vs. 44.00

  3. Ultrastructure of medial rectus muscles in patients with intermittent exotropia

    PubMed Central

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

    2016-01-01

    Purpose To study the ultrastructure of the medial rectus in patients with intermittent exotropia at different ages. Patients and methods The medial recti were harvested surgically from 20 patients with intermittent exotropia. Patients were divided into adolescent (age<18 years, n=10) and adult groups (age >18 years, n=10). The normal control group included five patients without strabismus and undergoing eye enucleation. Hematoxylin and eosin staining and transmission electron microscopy were used to visualize the medial recti. Western blot was used to determine the levels of myosin and actin. Results Varying fiber thickness, atrophy, and misalignment of the medial recti were visualized under optical microscope in patients with exotropia. Electron microscopy revealed sarcomere destruction, myofilament disintegration, unclear dark and light bands, collagen proliferation, and fibrosis. The adolescent group manifested significantly higher levels of myosin and actin than the adult group (P<0.05). Conclusion Younger patients with intermittent exotropia show stronger contraction of the medial recti compared with older patients. Our findings suggest that childhood was the appropriate time for surgery as the benefit of the intervention was better than in adulthood. PMID:26514242

  4. Excised larynx evaluation of subthyroid cartilage approach to medialization thyroplasty.

    PubMed

    Thompson, James D; Hoffman, Matthew R; Scholp, Austin; Devine, Erin E; Jiang, Jack J; McCulloch, Timothy M

    2017-09-11

    To describe an alternative approach to medialization thyroplasty involving dissection underneath the thyroid cartilage with placement of a Gore-Tex implant, and to evaluate its effect on a range of phonatory measures using an excised canine larynx model. Animal model. On each of eight excised canine larynges, the conditions of normal, paralysis, medialization thyroplasty by standard transthyroid cartilage approach, and medialization thyroplasty by experimental subthyroid cartilage approach were performed. Aerodynamic, acoustic, and mucosal wave parameters were measured for each condition. Compared to the vocal fold paralysis state, both the transthyroid and subthyroid approaches for Gore-Tex insertion resulted in significant decreases in phonation threshold pressure and phonation threshold flow. Both approaches also significantly decreased percent jitter, decreased percent shimmer, and improved signal-to-noise ratio. The mucosal wave was preserved after insertion of the Gore-Tex implant for both approaches. For all the phonatory measures except phonation threshold flow, there were no significant differences between the transthyroid and subthyroid approaches. Gore-Tex implantation via a subthyroid approach in an excised canine larynx model can produce effective medialization, preserve the mucosal wave, and significantly improve aerodynamic and acoustic parameters without meaningful difference compared to a traditional transthyroid approach. The subthyroid approach does not require creation of a thyroid cartilage window and could be a potentially valuable alternative method of performing medialization thyroplasty. NA Laryngoscope, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  5. 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

  6. In Vivo Performance of a Novel, Anatomically Shaped, Total Meniscal Prosthesis Made of Polycarbonate Urethane: A 12-Month Evaluation in Goats.

    PubMed

    Vrancken, Anne C T; Hannink, Gerjon; Madej, Wojciech; Verdonschot, Nico; van Tienen, Tony G; Buma, Pieter

    2017-10-01

    Injury or loss of the meniscus generally leads to degenerative osteoarthritic changes in the knee joint. However, the treatment options for symptomatic patients with total meniscectomy are limited. Therefore, we developed a novel, anatomically shaped, total meniscal implant made of polycarbonate urethane. To evaluate the in vivo performance of this novel total meniscal implant. The assessment particularly focused on the implant's response to long-term physiological loading in a goat model and its chondroprotective capacity in comparison to clinically relevant controls. Controlled laboratory study. Surgery was performed to the stifle joint of 26 female Saanen goats, subdivided into 4 groups: implant, allograft, total meniscectomy, and sham surgery. The sham group's contralateral joints served as nonoperated controls. After 12 months of follow-up, investigators evaluated implant wear, deformation, and the histopathological condition of the synovium and cartilage. Wear of the implant's articulating surfaces was minimal, which was confirmed by the absence of wear particles in the synovial fluid. Implant deformation was limited. However, one implant failed by complete tearing of the posterior horn extension. No differences in cartilage histopathological condition were observed for the implant, allograft, and meniscectomy groups. However, locally, the cartilage scores for these groups were significantly worse than those of the nonoperated controls. Whereas this study demonstrated that the novel implant is resistant to wear and that deformation after 12 months of physiological loading is acceptable, reinforcement of the implant horns is necessary to prevent horn failure. Although the implant could not protect the cartilage from developing degenerative changes, the progression of damage was similar in the allograft group. This novel polycarbonate urethane implant may have the potential to become an alternative treatment for symptomatic patients with total meniscectomy.

  7. Meniscal allograft transplantation

    MedlinePlus

    Meniscus transplant; Surgery - knee - meniscus transplant; Surgery - knee - cartilage; Arthroscopy - knee - meniscus transplant ... the lab for any diseases and infection. Other surgeries, such as ligament or cartilage repairs, may be ...

  8. 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 ...

  9. The meniscal healing process

    PubMed Central

    de Albornoz, Pilar Martínez; Forriol, Francisco

    2012-01-01

    Summary Meniscus is a difficult structure to repair and replace. An injured or degenerative meniscus promotes osteoarthritic joint changes that should be avoided. Research focused on promoting healing or replacement must cover three different working lines: biology, mechanics and surgical technique. Biology research line looks for specific factors able to develop a collagen tissue in a matrix with cells that joins the edges of the lesion and also looks for factors able to keep the elasticity and able to regenerate the damaged meniscus fibres. On the other side, scaffolds need the adequate viscoelasticity to allow the penetration of vessels and cells to avoid reabsorption. PMID:23738268

  10. A pseudo-iatrogenic case of medial clavicular fracture

    PubMed Central

    Staal, Heleen Muriel; Willems, Willem Jacob

    2008-01-01

    Medial fractures are the least common type of clavicular fracture (2–10%). The patient is a 29-year-old gynaecology resident with hyper-laxity and sternoclavicular instability. The latter had been surgically stabilized with Dacron® tape, which eroded the bone causing an usura. Acute right shoulder pain occurred 10 years later. CT revealed medial clavicular stress fracture. After 4 weeks of conservative management, internal fixation followed. Five months postoperatively the patient performed all activities without pain. In this patient the weakened medial clavicle due to usura clearly played a role in both the site and nature of the fracture. Furthermore, CT is essential in arriving at the correct diagnosis. PMID:18427920

  11. A pseudo-iatrogenic case of medial clavicular fracture.

    PubMed

    Poelmann, Tibor Antonius Johannes; Staal, Heleen Muriel; Willems, Willem Jacob

    2008-04-01

    Medial fractures are the least common type of clavicular fracture (2-10%). The patient is a 29-year-old gynaecology resident with hyper-laxity and sternoclavicular instability. The latter had been surgically stabilized with Dacron((R)) tape, which eroded the bone causing an usura. Acute right shoulder pain occurred 10 years later. CT revealed medial clavicular stress fracture. After 4 weeks of conservative management, internal fixation followed. Five months postoperatively the patient performed all activities without pain. In this patient the weakened medial clavicle due to usura clearly played a role in both the site and nature of the fracture. Furthermore, CT is essential in arriving at the correct diagnosis.

  12. Traumatic fragmented medial coronoid process in a Chihuahua.

    PubMed

    Hadley, H S; Wheeler, J L; Manley, P A

    2009-01-01

    Fragmented medial coronoid process (FMCP) is a disease process that has not previously been reported in toy-breed dogs. This report describes a presumptive case of FMCP in a 14-month-old Chihuahua that was presented for evaluation approximately four weeks following acute onset of moderate lameness in the left forelimb. Definitive diagnosis of a fragmented medial coronoid process was based upon computed tomography (CT) scan. A CT scan also demonstrated moderate joint incongruity in the affected elbow. Surgical removal of the fragment and subtotal coronoidectomy were performed via a medial arthrotomy. An ulnar ostectomy was also performed to address joint incongruity. Histology of specimens removed at surgery did not demonstrate evidence of microdamage as characteristic of FMCP in large breed dogs, and instead, suggested that the fracture was acute and traumatic in nature. Rapid return to function was observed following surgery.

  13. How I Do It: Medial Flap Inferior Turbinoplasty.

    PubMed

    Barham, Henry P; Knisely, Anna; Harvey, Richard J; Sacks, Raymond

    2015-01-01

    Techniques for inferior turbinate reduction vary from complete turbinectomy to limited cauterization. Surgical methods differ on the degree of tissue reduction and reliance on surgical tissue removal versus tissue ablation. The technique and surgical steps of our preferred method of turbinate reduction are presented. Critical steps include proper design of the medial flap and removal of turbinate bone and lateral mucosa to allow lateral positioning of the medial flap. Bipolar cautery of the inferior turbinate artery branches allows complete haemostasis and undermining of the head allows proper debulking of the anterior aspect of the turbinate and widening of the nasal valve area. The medial flap inferior turbinoplasty provides consistent, robust results. Long-term relief of obstructive symptoms without additional risk of complication is expected with this procedure.

  14. Isolated medial foot compartment syndrome after ankle sprain.

    PubMed

    Cortina, Josep; Amat, Carles; Selga, Jordi; Corona, Pablo Salvador

    2014-03-01

    Foot compartment syndrome is a serious potential complication of foot crush injury, fractures, surgery, and vascular injury. An acute compartment syndrome isolated to the medial compartment of the foot after suffering an ankle sprain is a rare complication. We report the case of a 31-year-old man who developed a medial foot compartment syndrome after suffering a deltoid ligament rupture at ankle while playing football. The patient underwent a medial compartment fasciotomy with resolution of symptoms. Compartment syndromes of the foot are rare and have been reported to occur after severe trauma. But, there are some reports in the literature of acute exertional compartment syndrome. In our case, the compartment syndrome appeared after an ankle sprain without vascular injuries associated. Copyright © 2013 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  15. Medial collateral ligament reconstruction in the baseball Pitcher's elbow.

    PubMed

    Erne, Holger C; Zouzias, Ioannis C; Rosenwasser, Melvin P

    2009-08-01

    Pitchers are prone to elbow injuries because of high and repetitive valgus stresses on the elbow. The anterior bundle of the medial ulnar collateral ligament (MCL) of the elbow is the primary restraint and is often attenuated with time, leading to functional incompetence and ultimate failure. Pitchers with a history of medial elbow pain, reduced velocity, and loss of command may have an MCL injury in evolution. Physical examination and imaging can confirm the diagnosis. Treatment begins with rest and activity modification. All medial elbow pain is not MCL injury. Surgery is considered only for talented athletes who wish to return to competitive play and may include elite scholastic and other collegiates and professionals. The technique for MCL reconstruction was first described in 1986. Many variations have been offered since then, which can result in predictable outcomes, allowing many to return to the same level of competitive play.

  16. Changes in articular cartilage following arthroscopic partial medial meniscectomy.

    PubMed

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

    2016-05-01

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

  17. Gore-Tex medialization laryngoplasty for treatment of dysphagia.

    PubMed

    Hendricker, Ryan M; deSilva, Brad W; Forrest, L Arick

    2010-04-01

    Gore-Tex medialization laryngoplasty is a well described procedure for the management of glottal incompetence with associated phonatory disturbance. Limited literature exists describing the use of this procedure in the management of dysphagia. We describe our experience with Gore-Tex medialization laryngoplasty and the treatment of dysphagia. Case series with chart review. Tertiary referral center. Between April 2000 and September 2008, 189 Gore-Tex medialization laryngoplasties were performed on 180 patients by the senior author. Complete records and analysis were available for and performed on 121 procedures for 113 patients. The main outcome measures were discontinuation of gastrostomy tube (g-tube) use or avoidance of g-tube, as well as clinical subjective improvement in swallowing function. Fifty-seven of 113 (50%) patients had complaints of dysphagia at presentation, with 47 of 57 (82%) having an objective swallowing evaluation. Thirty-two of 47 (68%) had documented penetration and/or aspiration. Twenty of 57 (35%) patients with dysphagia required g-tubes for alimentation. Eleven of 20 (55%) patients were able to discontinue g-tube use after Gore-Tex medialization laryngoplasty, and an additional five patients with aspiration were able to avoid need for g-tubes with Gore-Tex medialization laryngoplasty and swallowing therapy. Gore-Tex medialization laryngoplasty is a well tolerated and well described treatment for the management of glottal incompetence. The procedure is an appropriate adjunct in dysphagia management for the appropriate patient population. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  18. Medial circumflex femoral artery flap for ischial pressure sore

    PubMed Central

    Palanivelu, S.

    2009-01-01

    A new axial pattern flap based on the terminal branches of the medial circumflex femoral artery is described for coverage of ischial pressure sore. Based on the terminal branches of the transverse branch of medial circumflex femoral artery, which exit through the gap between the quadratus femoris muscle above and the upper border of adductor magnus muscle below, this fascio cutaneous flap is much smaller than the posterior thigh flap but extremely useful to cover ischeal pressure sores. The skin redundancy below the gluteal fold allows a primary closure of the donor defect. It can also be used in combination with biceps femoris muscle flap. PMID:19881020

  19. Afferent projections to the different medial amygdala subdivisions: a retrograde tracing study in the mouse.

    PubMed

    Cádiz-Moretti, Bernardita; Otero-García, Marcos; Martínez-García, Fernando; Lanuza, Enrique

    2016-03-01

    The medial amygdaloid nucleus (Me) is a key node in the socio-sexual brain, composed of anterior (MeA), posteroventral (MePV) and posterodorsal (MePD) subdivisions. These subdivisions have been suggested to play a different role in reproductive and defensive behaviours. In the present work we analyse the afferents of the three Me subdivisions using restricted injections of fluorogold in female outbred CD1 mice. The results reveal that the MeA, MePV and MePD shar