Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LIGAMENTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1991

Functional anatomy of the anterior cruciate ligament. Fibre bundle actions related to ligament replacements and injuries.

This work studied the fibre bundle anatomy of the anterior cruciate ligament. Three functional bundles--anteromedial, intermediate, and posterolateral--were identified in cadaver knees. Their contributions to resisting anterior subluxation in flexion and extension were found by repeated tests after sequential bundle transection. Changes of length in flexion and extension and in tibial rotation were measured. None of the fibres were isometric. The posterolateral bundle was stretched in extension and the anteromedial in flexion, which correlated with increased contributions to knee stability and the likelihood of partial ruptures in these positions. Tibial rotation had no significant effect. The fibre length changes suggested that the 'isometric point' aimed at by some ligament replacements lay anterior and superior to the femoral origin of the intermediate fibre bundle and towards the roof of the intercondylar notch.

Anterior Cruciate Ligament↗
PubMed2003

Evaluation of ligament fibroblast viability in ruptured cranial cruciate ligament of dogs.

OBJECTIVE: To determine fibroblast viability, assess development of apoptosis, and evaluate tissue hypoxia via histochemical, in-situ hybridization, or immunohistochemical staining in ruptured and intact cranial cruciate ligaments (CCLs) of dogs. ANIMALS: 32 dogs with ruptured CCLs, and 8 aged and 19 young dogs with intact CCLs. PROCEDURE: Markers of cell viability (lactate dehydrogenase [LDH]), apoptosis (terminal deoxynucleatidyl transferase-mediated deoxyuridine triphosphate-nick end labeling [TUNEL] method), and hypoxia (hypoxia-inducible factor-1alpha [HIF-1alpha] monoclonal antibody) were applied to CCL specimens; positive cells were assessed objectively (LDH) and subjectively (TUNEL and HIF-1alpha) in the main axial tissue component (core) and synovial intima and subintima (epiligamentous tissue). RESULTS: Viable fibroblasts were seen in all intact and ruptured CCLs. More nonviable cells were found in the core regions of ruptured CCLs and intact CCLs of young dogs than in the epiligamentous regions. Number of nonviable cells in the core region of ruptured CCLs was greater than that in intact CCLs of young and aged dogs, whereas the number in the epiligamentous region was similar in all specimens. The TUNEL and HIF-1alpha staining was only found in the epiligamentous region of ruptured CCLs. CONCLUSIONS AND CLINICAL RELEVANCE: Ruptured CCLs contained a high number of nonviable cells but not a great number of apoptotic cells. Repair processes in the epiligamentous region of the CCL include a metabolic response to hypoxia, suggesting that necrosis of ligament fibroblasts and transformation of surviving cells to a spheroid phenotype may be a response to hypoxia cause by microinjury or inadequate blood flow.

Aging↗
PubMed1994

An in vitro assay of anterior cruciate ligament (ACL) and medial collateral ligament (MCL) cell migration.

Explants from rabbit anterior cruciate ligaments (ACL) and medial collateral ligaments (MCL) were utilized to compare the relative rates that fibroblasts migrate onto glass and plastic culture surfaces in vitro. During the first two weeks in culture, a monolayer of cells appeared on the periphery of all the ACL and MCL explants. From 45 to 134 hrs in culture, the mean total MCL cell count per explant was 6-12 times greater than that for the ACL on the plastic culture dishes, and this difference was even greater for the cells attached to the glass cover slides over the explants. These differences were significant at the p < .005 level. The rates of cell proliferation were quite similar for primary cultures of ACL and MCL grown in the same medium as that used for the migration assay. The large difference in cell number at early times of culture is thus due to the more rapid MCL cell migration out of the explants, and not to a difference in the rate of cell proliferation. These data support the hypothesis that differences in cell migration rate play a role in the greater healing capacity of the MCL as compared with the ACL. The assay described in this work may then be useful in assessing factors that promote wound healing.

Animals↗
PubMed2001

Repair of chronic ruptures of the anterior cruciate ligament using allograft reconstruction and a ligament augmentation device.

A prospective study was performed to determine the effect of a ligament augmentation device (LAD) on the replacement of the anterior cruciate ligament (ACL) using tendon allografts. Twenty-five patients were followed for 66 to 98 months after tendon allograft replacement with LAD reinforcement for ACL rupture. The evaluation was done using the form of the International Knee Documentation Committee (IKDC), the Lysholm score and the Tegner scale. Two patients sustained a rerupture after major injury. Three other multiply-injured patients scored poorly because of associated injuries and fractures (IKDC grade D). Four patients scored normal (grade A), 12 patients nearly normal (grade B), and 5 patients abnormal (grade C). The Lysholm score showed 14 excellent (average 96), 5 good (average 86) and 4 fair results (average 76). Three patients with excellent results were IKDC grade C, solely because the xrays showed slight narrowing of the medial joint line, which might indeed indicate future problems. On the Tegner scale, the sports level decreased by an average of 1.4 points (from 7.25 to 5.83). Only five patients showed an anteroposterior displacement of more than 3 mm, of which only one was in the grade C group.

Adult↗
PubMed2003

Biomechanical study on the suture strength of ligament in cruciate ligament reconstruction.

OBJECTIVE: To test the suture strength on the tendon or ligament end and evaluate the stitch in the reconstruction of cruciate ligament and its clinical application. METHODS: Twenty-four specimens of patellar tendon with free ends were divided into 3 groups: Group I (3 Krackow stitches), Group II (2 Krackow stitches) and Group III (2 Krackow stitches with the first stitch passing through the tendon tissue as a modified Krackow stitch). These 3 groups were further divided into 6 subgroups according to different suture materials, No 1 Ethilon or stainless steel wire (phi=0.4 mm). Tensile test was undertaken to find out the least stitches with efficient suture pattern. RESULTS: Two Krackow locking stitches had stronger strength than 0.4 mm-diameter stainless steel wire. The fixation strength of 2 stitches with No 1 Ethilon was more than 80 N, superior to the failure strength of the material itself. The same strength was maintained if the first stitch was across the tendon tissue transversely. There was no statistically significant difference in the suture strength between 2 and 3 Krackow locking stitches. CONCLUSIONS: The suture strength is greater than the failure strength of the suture material. Less suture exposure can be achieved when the first stitch is across the tendon tissue while maintaining a comparable strength to other sutures. To attain higher suture strength, stronger materials or multiple strands rather than more stitches are preferred. Therefore, a rapid early rehabilitation of range of motion (ROM) is possible and reliable in practice.

Anterior Cruciate Ligament↗
PubMed1998

[Augmented anterior cruciate ligament replacement with the Kennedy-LAD (ligament augmentation device)--long term outcome].

The ligament augmentation device (Kennedy-LAD) is used to protect tendon grafts during the posttransplantation decrease in strength in anterior cruciate ligament (acl) reconstructions. The augmentation with the LAD is based on the concept of load sharing. Since 1983 we used the LAD in acl-reconstructions in 856 patients. In 63 cases we had to treat complications like infection (8), recurrent effusions (21), arthrofibrosis (34). The overall results are good with respect to stability, regain of strength and sports activity. In 73 cases resurgery was necessary because of synovitis (7), LAD-rupture due to re-injury (9), fatigue-rupture of the LAD (22), meniscal tears (35), 2.7 +/- 2.3 years (range: 2 months to 10 years) after LAD implantation. Modern techniques in acl reconstruction lead to comparable results without synthetic augmentation. Therefore, we now recommend the use of a LAD only in cases of repeated acl replacement with week tendon grafts, to avoid an allograft.

Adult↗
PubMed2002

Physiotherapist-led programmes and interventions for rehabilitation of anterior cruciate ligament, medial collateral ligament and meniscal injuries of the knee in adults.

BACKGROUND: Soft-tissue injuries of the knee, mainly involving the anterior cruciate ligament (ACL), the medial collateral ligament (MCL) and menisci, are common and their rehabilitation after non-surgical or surgical treatment often involves intensive and prolonged physiotherapy. OBJECTIVES: To examine the evidence for effectiveness of various physiotherapist-led (or 'directed') rehabilitation programmes, and of various interventions used within these programmes, for rehabilitation of acute or chronic ACL, MCL or meniscal injuries of the knee in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group's specialised register (to June 2001), MEDLINE (from 1966 to August 1999), EMBASE (from 1980 to February 1997), CINAHL (1982 to April 1999), CURRENT CONTENTS (up to March 1999) and reference lists of relevant articles, and consulted colleagues. Date of the most recent search: June 2001. SELECTION CRITERIA: Randomised or quasi-randomised clinical trials evaluating physiotherapist-led rehabilitation programmes, or components of rehabilitation programmes, for the treatment or post-surgical rehabilitation of ACL, MCL or knee meniscal injuries. Excluded were trials investigating electrical stimulation, or various interventions such as cryotherapy, immobilisation braces and continuous passive motion when used in initial or early treatment. Laboratory based trials reporting intermediate outcomes were also excluded. DATA COLLECTION AND ANALYSIS: All trials, judged as fitting the selection criteria by two reviewers, were independently assessed by two reviewers for methodological quality by use of an 11 item checklist. Data were independently extracted by two reviewers. Any disagreement was resolved by discussion. Although quantitative data from most trials are presented, using relative risks or mean differences together with 95 per cent confidence intervals, trial heterogeneity and lack of outcome data prevented meaningful pooling of results from comparable trials. MAIN RESULTS: Thirty-one trials, involving 1545 mainly young and male patients, met the inclusion criteria of the review. Methodological quality was highly variable: allocation concealment and / or assessor blinding were rare, and assessment of outcome was often incomplete and short-term. ACL injury and /or deficiency was the main focus of 18 trials, MCL injury of two trials, meniscal injury of nine trials and a mixture of soft-tissue injuries in the other two trials. The trial comparisons fell into five main categories: rehabilitation programme versus control (6 trials); one rehabilitation programme versus another (6 trials); different timing of rehabilitation (4 trials); one component of a programme versus another (6 trials); supplementary interventions to a programme versus none (9 trials). No trial provided sufficient evidence to establish the relative effectiveness of the intervention(s) under investigation. REVIEWER'S CONCLUSIONS: The available evidence for physiotherapist-led rehabilitation of ACL, MCL and meniscal injuries is wide ranging in terms of scope but insufficient to establish the relative effectiveness of the various approaches and methods in current use. There is a need for further research involving good quality, large scale randomised trials with sufficiently long follow-up to fully assess knee function and recovery.

Anterior Cruciate Ligament Injuries↗
PubMed1989

Injury of the anterior cruciate ligament: the role of collagenase in ligament degeneration.

Rapid degeneration of the anterior cruciate ligament (ACL) has been observed following acute ACL rupture. An understanding of this process might explain some of the poor clinical results of primary ACL repair. We created a surgical rabbit model of acute ACL injury and developed an in vitro assay for collagenase activity in the ACL and menisci. Microscopic evaluation revealed a rapidly degenerative process in injured ACLs, with loss of cellularity and matrix organization. This was associated with a significant increase in collagenase activity and a decrease in total collagen of the injured ACLs as compared with sham-operated controls. These findings confirm the observation that cut ACL ligament ends rapidly degenerate. This degenerative process might be partly due to a response of cells intrinsic to the ACL to injury. Left unchecked, this process may be detrimental to surgical attempts for primary ACL repair.

Animals↗
PubMed1990

The developmental morphology of a "periosteal" ligament insertion: growth and maturation of the tibial insertion of the rabbit medial collateral ligament.

The structural properties of ligament insertions change dramatically during growth and maturation, but little is known about their developmental anatomy. This study describes and quantifies changes in the gross and microscopic anatomy of the tibial insertion of the rabbit medial collateral ligament (MCL) during development and at skeletal maturity. Eighty animals were used for growth and descriptive studies. From this group, 27 animals, ranging in age from 1 to 24 months, were injected with fluorescent bone markers and their tibial insertions were processed undecalcified for histology. Sections were examined by polarized light and fluorescence microscopy to identify matrix and cells and to quantify mineral formation. Results showed that animals achieved histological skeletal maturity between 9 and 12 months of age. Body weights were a poor index of skeletal maturity. The tibial insertion was composed of five tissue layers, which changed proportions during growth and maturation. In immature animals, MCL fibers entered the periosteum; in older animals, MCL fibers were cemented to the tibia by advancing mineral. The tibial attachment of the MCL was thus transferred from the periosteum to the cortex during growth, suggesting that the term "periosteal insertion" is imprecise in adults. The hypothesis is put forward that these structural changes account for the reported increase in tensile failure of this insertion near skeletal maturity.

Aging↗
PubMed1990

Total decompression of the spinal cord for combined ossification of posterior longitudinal ligament and yellow ligament in the thoracic spine.

One of the causes of hyperostosis in the spinal canal, ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the yellow ligament (OYL) in the thoracic spine, can result in serious myelopathy, leading to sandwich-type compression of the spinal cord from anterior and posterior. For such cases we devised a treatment of total decompression of the spinal cord and intervertebral body fusion. This operation consists of two steps. The first step is designed for posterior and lateral decompression of the spinal cord by removal of the OYL following wide laminectomy. The second step is removal of the OPLL anteriorly for anterior decompression, followed by interbody fusion. As the final procedure of the first step, two deep parallel gutters, covering the extent of the OPLL to be removed anteriorly, are drilled down from the rear into the vertebral body along both sides of the dura. This pre-treatment makes removal of the OPLL anteriorly during the second stage much easier, faster, and safer. This operation is lengthy and demanding. However, based on our experience so far, it appears to be a promising surgical procedure.

Adult↗
PubMed1994

Nerve supply of anterior cruciate ligaments and of cryopreserved anterior cruciate ligament allografts: a new method for the differentiation of the nervous tissues.

We investigated the nerve supply of anterior cruciate ligaments ((ACLs) and of cryopreserved bone-ACL-bone allografts in a rabbit model with immunohistochemical methods to establish the distribution pattern of the nervous tissues and to determine the reinnervation rate of ACL allografts. The ACL is innervated by three different classes of nerve fibre: (1) fibres of large diameter, characterized by neurofilament immunoreactivity, which are fast-conducting mechanoreceptive sensory afferents; (2) fibres of small diameter, characterized by substance P-immunoreactivity, which are slow-conducting nociceptive sensory afferents; and (3) sympathetic efferent vasomotor fibres, characterized by their immunoreactivity to the rate-limiting enzyme of noradrenaline synthesis, tyrosine hydroxylase. The ACLs showed numerous fibres of all three nerve classes; as specialised sensory nerve endings only Ruffini corpuscles were observed. All nerve fibres were located subsynovially, none within the collagen core of the ligament itself. No nerve fibres were detected in the ACL allografts at 3 and 6 weeks. Sparse fibres were detected at 12 weeks, while the 24-, 36- and 52-week specimens showed plenty of all three fibre types. No mechanoreceptors were found in the ACL allografts. To our knowledge, this method for the first time allows a differentiation of the nerve fibres of ACLs and ACL allografts into three different nerve fibre classes with known neurophysiological functions.

Animals↗
PubMed2003

Restoration of anterior cruciate ligament-hamstring reflex arc after anterior cruciate ligament reconstruction.

It has recently been emphasized that restoration of neuromuscular function contributes to dynamic stability of the anterior cruciate ligament (ACL) reconstructed knee. The existence of an ACL-hamstring reflex arc, one of the protective ligament-muscular pathways, has been revealed in normal human knees. Although reinnervation to the reconstructed ACL has been observed histologically, it remains unclear whether the ACL-hamstring reflex arc is reestablished. This study examined the existence of the ACL-hamstring reflex arc in ACL-reconstructed knees by analyzing the changes in the hamstring EMG elicited by electrical stimulation to the reconstructed ACL. The patellar tendon grafts transplanted as an ACL substitute in three patients were electrically stimulated via a bipolar wire electrode inserted arthroscopically. The surface EMG was monitored from the ipsilateral biceps femoris and semitendinosus. In two of the three patients the significantly increased EMG value of the biceps femoris was detected between 120 and 140 ms after the onset of electrical ACL stimulation. The increased EMG activity detected in the biceps femoris after the stimulation to the patellar tendon graft indicated reestablishment of the ACL-hamstring reflex arc in the ACL-reconstructed knee.

Adult↗
PubMed1998

Combined hyperextension and supination of the elbow joint induces lateral ligament lesions. An experimental study of the pathoanatomy and kinematics in elbow ligament injuries.

An epidemiological study suggested that the injury mechanism of 'handball goalie's elbow' may be hyperextension. The pathomechanics of hyperextension combined with supination was studied in ten macroscopically normal, male, cadaveric elbow joint specimens. The age of the donors was 28.8 years (range 18-45 years). Extension loading of the elbow was performed in an experimental three-dimensional (3D)-kinematic loading apparatus. The degree of extension increased by 16.7 degrees +/- 8.7 degrees after loading. Hyperextension loads induced significant joint laxity in joint flexion (< 50 degrees) during forced valgus, external and internal rotation, respectively, but not during forced varus. The hyperextension trauma produced three lesions: (1) anterior capsule rupture, (2) avulsion of the proximal insertion of both the medial and the lateral collateral ligaments, and (3) occasional single rupture of the lateral collateral ligament. The lesions indicate that combined hyperextension and supination represent a possible mechanism leading to 'handball goalie's elbow'.

Adolescent↗
PubMed1994

Frayed ulno-triquetral and ulno-lunate ligaments as an arthroscopic sign of longstanding triquetro-lunate ligament rupture.

In patients with chronic wrist pain of more than 6 months duration, arthroscopy may reveal fraying of the ulno-triquetral and ulno-lunate ligaments. This can be a sign of longstanding triquetrolunate dissociation. We present a prospective study in which frayed ulno-triquetral (UT) and ulno-lunate (UL) ligaments were sought on wrist arthroscopy and correlated with longstanding triquetro-lunate (TL) rupture.

Adult↗
PubMedDate not supplied

Elbow joint laxity after experimental radial head excision and lateral collateral ligament rupture: efficacy of prosthetic replacement and ligament repair.

The objectives of this experimental study were to investigate the effect of radial head excision and lateral collateral ligament (LCL) division on elbow joint laxity and to determine the efficacy of radial head prosthetic replacement and LCL repair. Valgus, varus, internal rotation, and external rotation of the ulna were measured during passive flexion-extension and application of a 0.75-Nm torque in 6 intact cadaveric elbows and after (1) either excision of the radial head or division of the LCL, (2) removal of both constraints, (3) isolated radial head prosthetic replacement, (4) isolated LCL repair, and (5) radial head replacement combined with LCL repair. Isolated radial head excision increased varus (mean, 4.8 degrees) and external rotatory laxity (mean, 7.1 degrees), as did isolated LCL division (mean, 14.1 degrees for varus; mean, 14.7 degrees for external rotation). After removal of both constraints, varus and external rotatory laxities were increased by 19.0 degrees and 20.1 degrees, respectively, compared with the intact specimens. Isolated radial head replacement reduced mean varus laxity to 14.6 degrees and mean external rotatory laxity to 14.8 degrees. Isolated LCL repair normalized varus laxity but resulted in a 2.9 degrees increase in external rotatory laxity. The combined procedures restored laxity completely. The radial head is a constraint to varus and external rotation in the elbow joint, functioning by maintaining tension in the LCL. Still, removal of both constraints induces severe laxity, and in this case, prosthetic replacement may substitute for the constraining capacity of the native radial head. The combination of LCL repair and radial head replacement restores laxity completely, but an isolated LCL repair performs almost as well, probably by compensating for the ligamentous tension lost from radial head excision.

Adult↗
PubMed2003

Reconstruction of the iliofemoral ligament with an artificial ligament for recurrent anterior dislocation of total hip arthroplasty.

An 86-year-old woman underwent 4 revisions of hip arthroplasty and showed good position of both acetabular and femoral components. This was confirmed by roentgenographic measurements in the prone position. However, poor anterior acetabular covering after posterior inclination of the pelvis associated with lumbar kyphosis was observed in the standing position. Therefore, we reconstructed the iliofemoral ligament using a Leeds-Keio ligament to prevent anterior dislocation. At the 12-month follow-up evaluation, hip stability was confirmed, and the hip showed no further dislocation.

Aged↗