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Collateral Ligament (collateral + ligament)
Kinds of Collateral Ligament Selected AbstractsOsseous abnormalities associated with collateral desmopathy of the distal interphalangeal joint: Part 1EQUINE VETERINARY JOURNAL, Issue 8 2009Miss S. G. Dakin Summary Reasons for performing study: Osseous abnormalities. associated with collateral ligament (CL) injury of the distal interphalangeal (DIP) joint have been documented using magnetic resonance imaging (MRI) but there is currently limited information about the frequency of osseous pathology associated with CL injury. Objectives: To determine the frequency of occurrence of osseous abnormality coexistent with CL injury of the DIP joint and describe the distribution and character of osseous lesions; and to establish if there was an association between osseous abnormality and increased radiopharmaceutical uptake (IRU). Hypotheses: There would be a higher incidence of osseous abnormality at the insertion of an injured CL than at the origin; and a relationship between the presence of osseous abnormality and duration of lameness. Materials and methods: Magnetic resonance images of 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence and type of osseous abnormality in the middle and distal phalanges. Scintigraphic images were examined and the presence of IRU in the middle or distal phalanges recorded. Results: Osseous abnormalities were detected in 143 (45.7%) feet, 27 (18.8%) of which had osseous and CL injury alone, while the remaining 116 had CL related osseous injury and multiple injuries within the hoof capsule. Entheseous new bone and endosteal irregularity of the middle and distal phalanges were the most frequent types of osseous abnormality. There was a higher incidence of osseous abnormalities medially than laterally and at the ligament insertion than at the origin. There was a significant association between presence of IRU and osseous injury. Conclusions: A variety of osseous lesions of differing severity are associated with CL injury. Normal radiopharmaceutical uptake does not preclude significant osseous pathology associated with CL injury. Clinical relevance: Further studies are necessary in order to determine if osseous abnormalities associated with CL injury influence prognosis for return to performance. [source] Osseous abnormalities associated with collateral desmopathy of the distal interphalangeal joint.EQUINE VETERINARY JOURNAL, Issue 8 2009Part 2: Treatment, outcome Summary Reasons for performing study: There are currently few long-term follow-up data relating to recovery from injury of a collateral ligament (CL) of the distal interphalangeal (DIP) joint and limited information about the effect of associated osseous injury on prognosis. Objectives: To describe long-term follow-up results for horses with CL injury, with and without associated osseous injury; and to determine the effect of extracorporeal shock wave therapy (ECSWT) or radial pressure wave therapy (RPWT) on outcome. Hypotheses: Prognosis for return to performance for horses with CL-related osseous injury would be worse than for horses with CL injury alone. Methods: Magnetic resonance images from 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence of osseous abnormality associated with the ligament origin or insertion and the middle and distal phalanges. Horses were assigned to groups according to the combination of their injuries. Type of treatment was recorded and follow-up information obtained. Thirty-two horses with additional sources of lameness were excluded from analysis of outcome. Results: Follow-up data were available for 182 horses, 55 of which had follow-up information for up to 2 years after presentation. Twenty-seven percent of horses with CL injury alone and 34% of horses with CL related osseous injury returned to their previous performance level. Prognosis for a combination of injuries to multiple soft tissue and osseous structures within the hoof capsule was substantially worse. There was no effect of ECSWT or RPWT on outcome. Conclusions: The presence of mild to moderate CL related osseous injury does not appear to influence prognosis compared with CL injury alone. Clinical relevance: Further studies of a larger number of horses are necessary in order to ascertain if specific types of osseous pathology influence return to performance levels. [source] Sonographic diagnosis of acute injuries of the ulnar collateral ligament of the metacarpophalangeal joint of the thumbJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2007Takaaki Shinohara Abstract Purpose. To evaluate the significance of the ultrasonographic appearance of the aponeurosis for deciding the best treatment for ulnar collateral ligament (UCL) injuries of the thumb metacarpophalangeal joint. Methods. Fourteen patients (11 men, 3 women; mean age, 41 years; range, 15,66 years) who had an acute UCL tear were included. All patients were examined by ultrasonography (US) with a 7.5-MHz transducer and subsequently underwent surgery. The ultrasonographic findings were compared to the intraoperative findings. Results. UCL injuries were classified into two types by US according to the appearance of aponeurosis and its spatial relationship with the UCL: the intra-aponeurosis type (5 patients) and the extra-aponeurosis type (9 patients). In the 5 patients with intra-aponeurosis, ultrasonographic findings were well consistent with intraoperative findings. In contrast, extra-aponeurosis cases contained two different pathologies: of the 9 patients, 7 had so-called ,Stener lesions', one showed folding of a ruptured capsule, and one showed a ruptured aponeurosis. Conclusions. Because US is highly reliable in differentiating intra-aponeurosis from extra-aponeurosis types of injuries, the aponeurosis is a more reliable reference than Stener lesion for treatment decision by US. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound, 2007. [source] GDF-5/7 and bFGF activate integrin ,2-mediated cellular migration in rabbit ligament fibroblastsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2010Hirokazu Date Abstract Cellular activities responding to growth factors are important in ligament healing. The anterior cruciate ligament (ACL) has poor healing potential compared to the medial collateral ligament (MCL). To assess the differences, we investigated the proliferation, migration, adhesion, and matrix synthesis responding to growth factors in rabbit ACL and MCL fibroblasts. ACL cell proliferation to basic fibroblast growth factor (bFGF), bone morphogenetic protein-2, growth and differentiation factor (GDF)-5, and GDF-7 treatment was similar to that of MCL cells. GDF-5 enhanced Col1a1 expression in ACL and MCL fibroblasts up to 4.7- and 17-fold levels of control, respectively. MCL fibroblasts showed stronger migration activities in response to bFGF and GDF-5 than ACL cells. GDF-5/7 and bFGF also changed the stress fiber formation and cellular adhesion by modulating the distribution of integrin ,2. Functional blocking analyses using anti-integrin ,2 antibodies revealed that cellular migration responding to growth factors depended on the integrin ,2-mediated adhesion on type I collagen. The expression of integrin ,2 was also increased by growth factors in both cells. Our results demonstrate that GDF-5/7 and bFGF stimulate cellular migration by modulating integrin ,2 expression and integrin ,2-dependent adhesion, especially in MCL fibroblasts. These findings suggest that the different healing potential between ACL and MCL may be caused by different cellular behavior in the integrin ,2-mediated cellular migration in response to growth factors. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:225,231, 2010 [source] Periarticular ligament changes following ACL/MCL transection in an ovine stifle joint model of osteoarthritisJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2007Yusei Funakoshi Abstract Anterior cruciate ligament (ACL) injuries often lead to significant functional impairment, and are associated with increased risk for induction of degenerative joint disease. However, few studies have described the effect of ligament transection on the remaining intact knee ligaments. This study sought to determine specifically what impact combined ACL/medial collateral ligament (MCL) transection had on the remaining intact knee ligaments, particularly from the histological, biochemical, and molecular perspectives. Twenty weeks post-ACL/MCL transection, the cut ends of sheep MCLs were bridged by scar, while the posterior cruciate ligaments (PCLs) and lateral collateral ligaments (LCLs) seemed gross morphologically normal. Water content and cell density increased significantly in the MCL scars and the intact PCLs but were unchanged in the LCLs. Collagen fibril diameter distribution was significantly altered in both MCL scar tissue and uninjured PCLs from transected joints. MMP-13 mRNA levels in MCL scars and PCLs from ligament transected joints were increased, while TIMP-1 mRNA levels were significantly decreased in the PCLs only. This study has shown that some intact ligaments in injured joints are impacted by the injury. The joint appears to behave like an integrated organ system, with injury to one component affecting the other components as the "organ" attempts to adapt to the loss of integrity. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:997,1006, 2007 [source] Medial collateral ligament insertion site and contact forces in the ACL-deficient kneeJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2006Benjamin J. Ellis Abstract The objectives of this research were to determine the effects of anterior cruciate ligament (ACL) deficiency on medial collateral ligament (MCL) insertion site and contact forces during anterior tibial loading and valgus loading using a combined experimental-finite element (FE) approach. Our hypothesis was that ACL deficiency would increase MCL insertion site forces at the attachments to the tibia and femur and increase contact forces between the MCL and these bones. Six male knees were subjected to varus,valgus and anterior,posterior loading at flexion angles of ,0° and 30°. Three-dimensional joint kinematics and MCL strains were recorded during kinematic testing. Following testing, the MCL of each knee was removed to establish a stress-free reference configuration. An FE model of the femur,MCL,tibia complex was constructed for each knee to simulate valgus rotation and anterior translation at 0° and 30°, using subject-specific bone and ligament geometry and joint kinematics. A transversely isotropic hyperelastic material model with average material coefficients taken from a previous study was used to represent the MCL. Subject-specific MCL in situ strain distributions were used in each model. Insertion site and contact forces were determined from the FE analyses. FE predictions were validated by comparing MCL fiber strains to experimental measurements. The subject-specific FE predictions of MCL fiber stretch correlated well with the experimentally measured values (R2,=,0.95). ACL deficiency caused a significant increase in MCL insertion site and contact forces in response to anterior tibial loading. In contrast, ACL deficiency did not significantly increase MCL insertion site and contact forces in response to valgus loading, demonstrating that the ACL is not a restraint to valgus rotation in knees that have an intact MCL. When evaluating valgus laxity in the ACL-deficient knee, increased valgus laxity indicates a compromised MCL. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Long-term effects of porcine small intestine submucosa on the healing of medial collateral ligament: A functional tissue engineering studyJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2006Rui Liang Abstract Porcine small intestinal submucosa (SIS) was previously shown to enhance the mechanical properties of healing medial collateral ligaments (MCL), and the histomorphological appearance and collagen type V/I ratio were found to be close to those of normal MCL. We hypothesized that at a longer term, 26 weeks, SIS could guide a better organized neo-ligament formation, increasing mechanical properties and increasing collagen fibril diameters mediated by a reduction in collagen type V. A 6 mm gap injury in the right MCL was surgically created in 38 rabbits, while the contralateral intact MCL served as a sham-operated control. In half the animals, a strip of SIS was sutured onto the severed ends. In the other half, no SIS was applied. The cross-sectional area (CSA) was determined with a laser micrometer system. The femur,MCL,tibia complex was mechanically tested in uniaxial tension. Histomorphology was determined through H&E and immunofluorescent staining and transmission electron microscopy (TEM). Sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to determine collagen type V/I ratio. SIS-treated MCLs displayed a 28% reduction in CSA, a 33% increase in tangent modulus, and a 50% increase in tensile strength compared with the nontreated group (p,<,0.05). TEM showed groups of collagen fibrils with larger diameters in the SIS-treated ligaments in comparison with uniformly small fibrils for the nontreated group. H&E staining showed more densely stained collagen fibers in the SIS-treated group aligned along the longitudinal axis with more interspersed spindle-shaped cells. Immunofluorescent staining showed less collagen type V signals, confirmed by a 5% lower ratio of collagen type V/I compared with the nontreated controls (p,<,0.05). The findings extend the shorter term 12-week results, and support the potential of porcine SIS as a bioscaffold to enhance ligament healing. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Ligament creep recruits fibres at low stresses and can lead to modulus-reducing fibre damage at higher creep stresses: a study in rabbit medial collateral ligament modelJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2002G. M. Thornton Ligaments are subjected to a range of loads during different activities in vivo, suggesting that they must resist creep at various stresses. Cyclic and static creep tests of rabbit medial collateral ligament were used as a model to examine creep over a range of stresses in the toe- and linear-regions of the stress,strain curve: 4.1 MPa (n =7), 7.1 MPa (n = 6), 14 MPa (n = 9) and 28 MPa (n = 6). We quantified ligament creep behaviour to determine if, at low stresses, modulus would increase in a cyclic creep test and collagen fibres would be recruited in a static creep test. At higher creep stresses, a decrease in measured modulus was expected to be a potential marker of damage. The increase in modulus during cyclic creep and the increase in strain during static creep were similar between the three toe-region stresses (4.1, 7.1, 14 MPa). However, at the linear-region stress (28 MPa), both these parameters increased significantly compared to the increases at the three toe-region stresses. A concurrent crimp analysis revealed that collagen fibres were recruited during creep, evidenced by decreased area of crimped fibres at the end of the static creep test. Interestingly, a predominance of straightened fibres was observed at the end of the 28 MPa creep test, suggesting a limited potential for fibre recruitment at higher, linear-region stresses. An additional 28 MPa (n = 6) group had mechanically detectable discontinuities in their stress,strain curves during creep that were related to reductions in modulus and suggested fibre damage. These data support the concept that collagen fibre recruitment is a mechanism by which ligaments resist creep at low stresses. At a higher creep stress, which was still only about a third of the failure capacity, damage to some ligaments occurred and was marked by a sudden reduction in modulus. In the cyclic tests, with continued cycling, the modulus increased back to original values obtained before the discontinuity suggesting that other fibres were being recruited to bear load. These results have important implications for our understanding of how fibre recruitment and stress redistribution act in normal ligament to minimize creep and restore modulus after fibre damage. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Healing of subfailure ligament injury: comparison between immature and mature ligaments in a rat modelJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2002Paolo P. Provenzano This study evaluated biomechanical properties of healing ligament following subfailure (grade II) injury by comparing young and mature animals in a rat lateral collateral ligament (LCL) model. One randomly selected LCL was stretched in situ using a custom designed device in eighteen young (21 days) and eighteen skeletally mature (8 months) male rats. Animals were euthanized at 0, 7, and 14 days post-surgery, and ligament ultimate stress, strain at failure and laxity were determined (n = 6 pairs per group). At time 0 after introduction of stretch injury, ligament laxity was present in both groups. The mature rats had 54 ± 9% strength of the control while the immature rats had 58 ± 11% of the strength of the control, representing a consistent and significant injury. The immature and mature ligaments showed similar patterns of cellular damage post-injury and had similar modes of mechanical failure. Ligament laxity decreased in each group as healing time increased, however ligament laxity did not completely recover in either group after 2 weeks of healing. After 7 and 14 days of healing, the mature rats, respectively, had only 63 ± 14% and 80 ± 8% strengths of the controls while the immature rats had 94 ± 6% and 94 ± 10%. Hence, mechanical data showed that immature animals recovered their strength after a grade II sprain at a faster rate than mature animals. However, ligament laxity was still present in both groups two weeks after the injury and was not completely removed by growth in the immature group. These findings are clinically relevant since joint laxity after injury is common, and these results may explain the presence of continued instability in a joint injured at a young age. Hence, this study, with a new injury model, showed differences in ligament healing associated with maturity and quantified the clinically observed persistance of ligament laxity. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Medial collateral ligament autografts have increased creep response for at least two years and early immobilization makes this worseJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2002G. M. Thornton Recent evidence has shown that 10,40% of knee joints reconstructed with soft-tissue autografts have a recurrence of abnormal joint laxity over time. One possible explanation is the "stretching out" (or unrecovered creep) of the graft tissue. To test in vitro creep and creep recovery of fresh anatomic ligament autografts in an extra-articular environment, 16 rabbits underwent an orthotopic medial collateral ligament (MCL) autograft procedure to one hindlimb. Three subgroups of animals had either unrestricted cage activity for 1 year (n = 5) or 2 years (n = 5) or pin-immobilization for the first 6 weeks followed by cage activity for the remainder of 1 year (n = 6). Following laxity measurements, to test their creep response, isolated MCL grafts were cyclically and then statically creep tested in vitro at 4.1 MPa, allowed to recover at zero load for 20 min, and finally elongated to failure. Due to differences in cross-sectional area between the grafts and normal MCLs, two normal control groups were tested: stress-matched tested at 4.1 MPa (16.2 N; n = 7) and force-matched tested at 29.1 N (7.1 MPa; n = 6). Ligament grafts had normal laxity but significantly increased creep and decreased creep recovery compared to normal MCLs after 1 and 2 years of healing (p < 0.0004). Graft failure stress was also significantly less than normal (p < 0.0001). Immobilized grafts had significantly greater creep compared to non-immobilized grafts at 1 year of healing (p < 0.05). These results support previous observations concerning material inferiority of fresh anatomic rabbit MCL autografts, but add the concept that such grafts also have increased potential to creep with either slower or incomplete recovery when subjected to low stresses in vitro. Joint and ligament laxities in situ were normal in this model, however, suggesting either that in vivo MCL graft stresses are lower than those used here in vitro or that these tissues have other mechanisms by which they can recover their functional length in vivo. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Compressive compared with tensile loading of medial collateral ligament scar in vitro uniquely influences mRNA levels for aggrecan, collagen type II, and collagenaseJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2000Tokifumi Majima To test the hypothesis that loading conditions can be used to engineer early ligament scar behaviors, we used an in vitro system to examine the effect that cyclic hydrostatic compression and cyclic tension applied to 6-week rabbit medial collateral ligament scars had on mRNA levels for matrix molecules, collagenase, and the proto-oncogenes c-fos and c-jun. Our specific hypothesis was that tensile stress would promote more normal mRNA expression in ligament whereas compression would lead to higher levels of mRNA for cartilage-like molecules. Femur (injured medial collateral ligament)-tibia complexes were subjected to a hydrostatic pressure of 1 MPa or a tensile stress of 1 MPa of 0.5 Hz for 1 minute followed by 14 minutes of rest. On the basis of a preliminary optimization experiment, this 15-minute testing cycle was repeated for 4 hours. Semiquantitative reverse transcription-polymerase chain reaction analysis was performed for mechanically treated medial collateral ligament scars with use of rabbit specific primer sets for types I, II, and III collagen, decorin, biglycan, fibromodulin, versican, aggrecan, collagenase, c-fos, c-jun, and a housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase. Cyclic hydrostatic compression resulted in a statistically significant increase in mRNA levels of type-II collagen (171% of nonloaded values) and aggrecan (313% of nonloaded values) but statistically significant decreases in collagenase mRNA levels (35% of nonloaded values). Cyclic tension also resulted in a statistically significant decrease in collagenase mRNA levels (66% of nonloaded values) and an increase in aggrecan mRNA levels (458% of nonloaded values) but no significant change in the mRNA levels for the other molecules. The results show that it is possible to alter mRNA levels for a subset of genes in scar tissue by supplying unique mechanical stimuli in vitro and thus that further investigation of scar engineering for potential reimplantation appears feasible. [source] A simplified technique for diagnostic and surgical arthroscopy of the shoulder joint in the dogJOURNAL OF SMALL ANIMAL PRACTICE, Issue 1 2002F. M. Martini A modified technique is presented for surgical and diagnostic arthroscopy of the shoulder joint in the dog. The technique involves access to the joint through two points only; one was created in place of the drainage needle-cannula, which was replaced with a portal, while the second was located more caudally compared with previous techniques. Using a changing guide rod system the two portals are completely interchangeable in order to perform easier arthroscopic surgery either in the cranial or caudal aspect of the joint. The presence of only one portal caudal to the lateral collateral ligament allows more freedom of movement and avoids interference between the arthroscope and the instruments. The modified procedure was performed on 33 joints affected by osteochondritis dissecans or tenoligament diseases and facilitated straightforward diagnostic examinations, and simple and rapid surgical procedures. [source] Surgical treatment of "terrible triad of the elbow": technique and outcomeORTHOPAEDIC SURGERY, Issue 2 2010Yu-xing Wang MD Objective:, To describe the authors' surgical technique and to evaluate the final functional outcome of surgical treatment of the "terrible triad of the elbow". Methods:, Eight patients identified with "terrible triad" injury patterns, including posterior elbow dislocation, radial head fracture and coronoid fracture, were available for a minimum of 11 months follow-up. Evaluation of functional outcome was based on Mayo elbow performance, Broberg-Morrey scores, and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Complications were also recorded. Results:, Five elbows redislocated while in a splint after manipulative reduction. Three had residual subluxation after operative treatment. The final mean extent of forearm movement was as follows: 21° of extension deficit (range, 5° to 45°), 126° of flexion (range, 110° to 140°), 75° of supination (range, 45° to 90°), and 71° of pronation (range, 30° to 90°). The mean Mayo, Broberg-Morrey, and DASH scores were 78.0 ± 13.4, 76.0 ± 14.0, and 28.0 ± 24.7, respectively. Conclusions:, When an elbow joint is affected by the terrible triad, it is very unstable and prone to numerous complications. With operative treatment, the surgeon should attempt to perform internal fixation of the coronoid fracture, to regain normal radiocapitellar contact (either by preserving the radial head with open reduction and internal fixation (ORIF) or by replacing it with a prosthesis), and to repair the lateral collateral ligament (LCL). Thus early functional recovery and a successful final functional outcome can be achieved. [source] Resemblance of osteophytes in experimental osteoarthritis to transforming growth factor ,,induced osteophytes: Limited role of bone morphogenetic protein in early osteoarthritic osteophyte formationARTHRITIS & RHEUMATISM, Issue 12 2007E. N. Blaney Davidson Objective Osteoarthritis (OA) is characterized by cartilage damage, synovial fibrosis, and osteophyte formation. Both transforming growth factor , (TGF,) and bone morphogenetic protein 2 (BMP-2) can induce the formation of osteophytes during OA, but their specific role in this process is unclear. The purpose of this study was to investigate the respective contributions of TGF, and BMP-2 to OA. Methods Mouse knee joints injected with adenovirus (Ad-TGF, or Ad-BMP-2) were compared histologically with knee joints from murine models of OA (joints injected with collagenase and joints from STR/Ort mice with spontaneous OA). To further investigate the role of BMP during osteophyte formation, adenovirus Ad-Gremlin was injected into knee joints that had previously been injected with Ad-TGF, or collagenase. Results BMP-2 induced early osteophytes, which bulged from the growth plates on the femur and grew on top of the patella, whereas TGF, induced early osteophyte formation on the bone shaft beneath the collateral ligament on the femur as well as on top of the patella. The pattern of osteophyte formation during experimental OA closely resembled that of TGF,-induced osteophyte formation, but differed from the pattern induced by BMP-2. Ad-Gremlin proved to be able to totally block BMP-2,induced osteophyte formation. However, blocking BMP activity inhibited neither TGF,-induced nor experimental OA,associated osteophyte formation. Conclusion Our findings demonstrate that the role of BMP during the onset of TGF,-induced and experimental OA,induced osteophyte formation is limited. The latter finding does not rule out a role of BMP during osteophyte maturation. [source] Gene deletion of either interleukin-1,, interleukin-1,,converting enzyme, inducible nitric oxide synthase, or stromelysin 1 accelerates the development of knee osteoarthritis in mice after surgical transection of the medial collateral ligament and partial medial meniscectomyARTHRITIS & RHEUMATISM, Issue 12 2003Kristen M. Clements Objective To investigate the development of osteoarthritis (OA) after transection of the medial collateral ligament and partial medial meniscectomy in mice in which genes encoding either interleukin-1, (IL-1,), IL-1,,converting enzyme (ICE), stromelysin 1, or inducible nitric oxide synthase (iNOS) were deleted. Methods Sectioning of the medial collateral ligament and partial medial meniscectomy were performed on right knee joints of wild-type and knockout mice. Left joints served as unoperated controls. Serial histologic sections were obtained from throughout the whole joint of both knees 4 days or 1, 2, 3, or 4 weeks after surgery. Sections were graded for OA lesions on a scale of 0,6 and were assessed for breakdown of tibial cartilage matrix proteoglycan (aggrecan) and type II collagen by matrix metalloproteinases (MMPs) and aggrecanases with immunohistochemistry studies using anti-VDIPEN, anti-NITEGE, and Col2-3/4Cshort neoepitope antibodies. Proteoglycan depletion was assessed by Alcian blue staining and chondrocyte cell death, with the TUNEL technique. Results All knockout mice showed accelerated development of OA lesions in the medial tibial cartilage after surgery, compared with wild-type mice. ICE-, iNOS-, and particularly IL-1,,knockout mice developed OA lesions in the lateral cartilage of unoperated limbs. Development of focal histopathologic lesions was accompanied by increased levels of MMP-, aggrecanase-, and collagenase-generated cleavage neoepitopes in areas around lesions, while nonlesional areas showed no change in immunostaining. Extensive cell death was also detected by TUNEL staining in focal areas around lesions. Conclusion We postulate that deletion of each of these genes, which encode molecules capable of producing degenerative changes in cartilage, leads to changes in the homeostatic controls regulating the balance between anabolism and catabolism, favoring accelerated cartilage degeneration. These observations suggest that these genes may play important regulatory roles in maintaining normal homeostasis in articular cartilage matrix turnover. [source] Influence of the position of the foot on MRI signal in the deep digital flexor tendon and collateral ligaments of the distal interphalangeal joint in the standing horseEQUINE VETERINARY JOURNAL, Issue 5 2009M. SPRIET Summary Reasons for performing study: Hyperintense signal is sometimes observed in ligaments and tendons of the equine foot on standing magnetic resonance examination without associated changes in size and shape. In such cases, the presence of a true lesion or an artifact should be considered. A change in position of a ligament or tendon relative to the magnetic field can induce increased signal intensity due to the magic angle effect. Objectives: To assess if positional rotation of the foot in the solar plane could be responsible for artifactual changes in signal intensity in the collateral ligaments of the distal interphalangeal joint and in the deep digital flexor tendon. Methods: Six isolated equine feet were imaged with a standing equine magnetic resonance system in 9 different positions with different degrees of rotation in the solar plane. Results: Rotation of the limb induced a linear hyperintense signal on all feet at the palmar aspect of one of the lobes of the deep digital flexor tendon and at the dorsal aspect of the other lobe. Changes in signal intensity in the collateral ligaments of the distal interphalangeal joint occurred with rotation of the limb only in those feet where mediolateral hoof imbalance was present. Conclusions: The position and conformation of the foot influence the signal intensity in the deep digital flexor tendon and in the collateral ligaments of the distal interphalangeal joint. Potential relevance: The significance of increased signal intensity in the deep digital flexor tendon and in the collateral ligaments of the distal interphalangeal joint should be interpreted with regard to the position and the conformation of the foot. [source] Magnetic resonance imaging evaluation of 264 horses with foot pain: The podotrochlear apparatus, deep digital flexor tendon and collateral ligaments of the distal interphalangeal jointEQUINE VETERINARY JOURNAL, Issue 4 2007S. DYSON Summary Reasons for performing study: To improve understanding of the interrelationships between injuries of the podotrochlear apparatus and deep digital flexor tendon (DDFT). Hypotheses: There is a difference in frequency of different types of lesions at different anatomical sites of the DDFT. Lesions of the collateral sesamoidean ligament (CSL), distal sesamoidean impar ligament (DSIL), distal interphalangeal (DIP) joint and navicular bursa are seen in association with lesions of the navicular bone. Methods: The magnetic resonance (MR) images of 264 horses with unilateral or bilateral foot pain were analysed and graded. Descriptive statistics were performed to establish the frequency of occurrence of DDFT lesion types at different anatomical levels, and lesions of the CSL, DSIL, navicular bursa, DIP joint and collateral ligaments (CLs) of the DIP joint. A Chi-square test was used to test for a difference in the proportion of navicular bone grades between limbs with and without DDFT lesions at each level, and to compare navicular bone grades for limbs with and without each of DSIL, CSL, navicular bursa or DIP joint lesions. Results: Lesions of the DDFT occurred in 82.6% of limbs, occurring most commonly at the level of the CSL (59.4%) and the navicular bone (59.0%). Core lesions predominated at the level of the proximal phalanx (90.3%), whereas at the level of the CSL and navicular bone core lesions, sagittal splits and dorsal abrasions were most common. There was a positive association between DDFT lesions and navicular bone pathology involving all aspects of the bone. Lesions of the DSIL (38.2% limbs) were more common than those of the CSL (10.5%), but the presence of either was associated with abnormalities of the navicular bone, especially involving the proximal or distal borders and the medulla. Conclusions and clinical relevance: There are close interactions between injuries of the components of the podotrochlear apparatus, the DDFT, the navicular bursa and the DIP joint. Further knowledge about the biomechanical risk factors for injury may have importance for both disease prevention and management. [source] The hip joint: the fibrillar collagens associated with development and ageing in the rabbitJOURNAL OF ANATOMY, Issue 1 2001YVETTE S. BLAND The fibrillar collagens associated with the articular cartilages, joint capsule and ligamentum teres of the rabbit hip joint were characterised from the 17 d fetus to the 2-y-old adult by immunohistochemical methods. Initially the putative articular cartilage contains types I, III and V collagens, but when cavitation is complete in the 25 d fetus, type II collagen appears. In the 17 d fetus, the cells of the chondrogenous layers express type I collagen mRNA, but not that of type II collagen. Types III and V collagens are present throughout life, particularly pericellularly. Type I collagen is lost. In all respects, the articular cartilage of the hip joint is similar to that of the knee. The joint capsule contains types I, III and V collagens. In the fetus the ligamentum teres contains types I and V collagens and the cells express type I collagen mRNA; type III collagen is confined mainly to its surface and insertions. After birth, the same distribution remains, but there is more type III collagen in the ligament, proper. The attachment to the cartilage of the head of the femur is marked only by fibres of type I collagen traversing the cartilage; the attachment cannot be distinguished in preparations localising types III and V collagens. The attachment to the bone at the lip of the acetabulum is via fibres of types I and V collagens and little type III is present. The ligament is covered by a sheath of types III and V collagens. Type II collagen was not located in any part of the ligamentum teres. The distribution of collagens in the ligamentum teres is similar to that in the collateral ligaments of the knee. Its insertions are unusual because no fibrocartilage was detected. [source] Variations in the normal anatomy of the collateral ligaments of the human elbow jointJOURNAL OF ANATOMY, Issue 3 2000K. S. BECKETT The variations which occur in the medial and lateral ligament complexes of the elbow were investigated. These occurred frequently with the standard appearances occurring in no more than half the specimens on the medial side and one quarter of those on the lateral side. Surgeons who regularly perform elbow arthroplasty must be aware of these considerations, especially with the introduction of unconstrained prostheses which rely upon the ligament complex for their postoperative stability. [source] Genome-wide expression analysis of intra- and extraarticular connective tissueJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2009Richard V. Pearse II Abstract In comparison to extraarticular ligaments and tendons, the intraarticular ligaments such as the anterior and posterior cruciates exhibit different biochemical, biomechanical, and viscoelastic properties and most importantly, differential abilities to heal after surgical repair. Little is known about the underlying basis for these differences, in large measure due to the paucity of molecular markers distinguishing different classes of tendons and ligaments. To date, there has been no systematic analysis of gene expression differences between different types of connective tissues. We used Affymetrix expression arrays to analyze the differences in gene expression levels between the anterior cruciate, posterior cruciate, and medial collateral ligaments, the patellar and Achilles tendons and the synovium. We have identified five clusters of gene cohorts displaying similar expression patterns. These clusters group into three categories including: (1) genes that are strongly expressed in all connective tissues compared to the synovium control tissue; (2) genes that distinguish intraarticular connective tissues from extraarticular connective tissues; and (3) a group of genes expressed in common by the patellar tendon and the synovium. Our analysis identifies a new marker of tendons and ligaments (fibin2), demonstrates molecular diversity between subtypes of tendons and ligaments, and indicates that the primary molecular subdivision among dense regular connective tissues is intra- versus extraarticular rather than ligament versus tendon. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 427,434, 2009 [source] Periarticular ligament changes following ACL/MCL transection in an ovine stifle joint model of osteoarthritisJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2007Yusei Funakoshi Abstract Anterior cruciate ligament (ACL) injuries often lead to significant functional impairment, and are associated with increased risk for induction of degenerative joint disease. However, few studies have described the effect of ligament transection on the remaining intact knee ligaments. This study sought to determine specifically what impact combined ACL/medial collateral ligament (MCL) transection had on the remaining intact knee ligaments, particularly from the histological, biochemical, and molecular perspectives. Twenty weeks post-ACL/MCL transection, the cut ends of sheep MCLs were bridged by scar, while the posterior cruciate ligaments (PCLs) and lateral collateral ligaments (LCLs) seemed gross morphologically normal. Water content and cell density increased significantly in the MCL scars and the intact PCLs but were unchanged in the LCLs. Collagen fibril diameter distribution was significantly altered in both MCL scar tissue and uninjured PCLs from transected joints. MMP-13 mRNA levels in MCL scars and PCLs from ligament transected joints were increased, while TIMP-1 mRNA levels were significantly decreased in the PCLs only. This study has shown that some intact ligaments in injured joints are impacted by the injury. The joint appears to behave like an integrated organ system, with injury to one component affecting the other components as the "organ" attempts to adapt to the loss of integrity. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:997,1006, 2007 [source] Long-term effects of porcine small intestine submucosa on the healing of medial collateral ligament: A functional tissue engineering studyJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2006Rui Liang Abstract Porcine small intestinal submucosa (SIS) was previously shown to enhance the mechanical properties of healing medial collateral ligaments (MCL), and the histomorphological appearance and collagen type V/I ratio were found to be close to those of normal MCL. We hypothesized that at a longer term, 26 weeks, SIS could guide a better organized neo-ligament formation, increasing mechanical properties and increasing collagen fibril diameters mediated by a reduction in collagen type V. A 6 mm gap injury in the right MCL was surgically created in 38 rabbits, while the contralateral intact MCL served as a sham-operated control. In half the animals, a strip of SIS was sutured onto the severed ends. In the other half, no SIS was applied. The cross-sectional area (CSA) was determined with a laser micrometer system. The femur,MCL,tibia complex was mechanically tested in uniaxial tension. Histomorphology was determined through H&E and immunofluorescent staining and transmission electron microscopy (TEM). Sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to determine collagen type V/I ratio. SIS-treated MCLs displayed a 28% reduction in CSA, a 33% increase in tangent modulus, and a 50% increase in tensile strength compared with the nontreated group (p,<,0.05). TEM showed groups of collagen fibrils with larger diameters in the SIS-treated ligaments in comparison with uniformly small fibrils for the nontreated group. H&E staining showed more densely stained collagen fibers in the SIS-treated group aligned along the longitudinal axis with more interspersed spindle-shaped cells. Immunofluorescent staining showed less collagen type V signals, confirmed by a 5% lower ratio of collagen type V/I compared with the nontreated controls (p,<,0.05). The findings extend the shorter term 12-week results, and support the potential of porcine SIS as a bioscaffold to enhance ligament healing. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Microanatomic studies to define predictive factors for the topography of periarticular erosion formation in inflammatory arthritisARTHRITIS & RHEUMATISM, Issue 4 2009Dennis McGonagle Objective The microanatomic basis for formation of erosions in inflammatory arthritis is incompletely understood but is thought to be related to bare areas and the associated cartilage,synovium junction. The purpose of this study was to test the hypothesis that erosion-prone sites are associated with microdamage in macroscopically normal joints. Methods Histologic evaluation of erosion-prone sites was performed on 20 collateral ligaments (CLs) from the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of 5 normal cadavers. In addition, the MCP joints (n = 17) and PIP joints (n = 3) of 20 patients with rheumatoid arthritis (RA) were assessed by computed tomography (CT) to ascertain whether the topography of erosion formation in patients with RA corresponded to the cadaveric findings. Results Absence of a bare area was noted in cadaveric tissue at the periligamentous erosion-prone regions, especially in the distal MCP joints and both distal and proximal PIP joints. Nevertheless, these sites exhibited soft-tissue pathologic features and bony microdamage/cyst formation. Other significant findings included the presence of pannus without inflammatory changes in the regions in which a bare area was absent, and the replacement of bare area regions with fibrovascular synovial tissue in joints without inflammatory changes. The sites of cadaveric tissue microdamage corresponded to CT-determined erosion formation in the MCP and PIP joints of patients with RA, in whom erosions adjacent to the CLs were more common than dorsal or volar erosions. Conclusion Periarticular erosion formation may not necessarily depend on the presence of a bare area and has a propensity to occur adjacent to ligaments in which bone microdamage is common. These findings suggest that periligamentous locations prone to microdamage may critically influence the topography of erosion formation in inflammatory arthritis. [source] Elbow joint luxation in a 1-month-old foalAUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2008LM Rubio-Martínez This paper reports on luxation of the elbow joint without concomitant fracture in a 1-month-old foal. Conservative treatment, with closed reduction and full-limb bandaging, including caudal and lateral splints, seemed successful initially, however, failed to provide enough stability and luxation recurred, and open reduction and surgical placement of prosthetic collateral ligaments was required. Luxation of the elbow joint should be considered when acute non-weight bearing forelimb lameness occurs associated with pain and swelling in the area of the elbow in young foals. Closed reduction failed to provide sufficient joint stability. [source] | |||||||||||||