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 1,729 records · Page 96Linked to original sources
PubMed2003

Contrasting responses of human gingival and periodontal ligament fibroblasts to bacterial cell-surface components through the CD14/Toll-like receptor system.

We compared human periodontal ligament fibroblasts with human gingival fibroblasts isolated from the same donor to examine interleukin-8 (IL-8) responses of the cells to Salmonella lipopolysaccharide, a water-soluble peptidoglycan from Staphylococcus epidermidis and the synthetic muramyldipeptide, with special reference to the possible involvement of the CD14/Toll-like receptor (TLR) system of the cells in the responses. Human gingival fibroblasts expressed CD14 on their surfaces and strongly expressed CD14 mRNA, while human periodontal ligament fibroblasts showed considerably lower levels of expression in both respects. Both cells expressed mRNA of TLR-related molecules, i.e. TLR2, TLR4, MD-2 and MyD88, although human periodontal ligament fibroblasts expressed TLR2 more strongly than human gingival fibroblasts. Human gingival fibroblasts exhibited a stronger IL-8 response than human periodontal ligament fibroblasts to lipopolysaccharide, while human periodontal ligament fibroblasts exhibited a response comparable to, or slightly stronger than, that of human gingival fibroblasts to S. epidermidis peptidoglycan and muramyldipeptide. The IL-8 responses of both cells to lipopolysaccharide and S. epidermidis peptidoglycan were completely inhibited by antihuman CD14 monoclonal antibody (MAb). The responses of both cells to lipopolysaccaride were significantly inhibited by antihuman TLR4 MAb, while those to S. epidermidis peptidoglycan were inhibited by antihuman TLR2 MAb. In contrast, muramyldipeptide activated both types of cells in a TLR2- and TLR4-independent manner, although the activities of muramyldipeptide on human gingival fibroblasts, but not human periodontal ligament fibroblasts, were significantly inhibited by anti-CD14 MAb.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed2001

Occlusal hypofunction causes changes of proteoglycan content in the rat periodontal ligament.

The biological functions of proteoglycans and glycosaminoglycans are closely associated with mechanical stress on the tissue. In order to reveal the relationship between proteoglycans in the periodontal ligament and mechanical stress such as occlusal stimuli, occlusal hypofunction of rat unilateral mandibular molars was induced by extraction of the opposing first, second and third maxillary molars. Immunohistochemical analyses were performed using antibodies for chondroitin sulfate, decorin, biglycan, heparan sulfate and keratan sulfate, and hyaluronic acid-binding protein. Chondroitin sulfate, observed more strongly in the cervical side than in the apical side of the periodontal ligament of the unextracted sides of mandible, and uniformly present in the extracellular matrix of the periodontal ligament, decreased significantly from 1 wk post-extraction of the antagonists, with a decrease in thickness and disarrangement in fibrous components. Decorin core protein, uniformly present in the periodontal ligament of the unextracted sides, decreased as early on as 2 d post-extraction. Heparan sulfate, mainly localized on the cell surface of vascular endothelial cells and osteoclastic cells as well as in the extracellular matrix of the unextracted sides, decreased significantly in association with the decreased number of blood vessels and osteoclastic cells as early on as 2 d post-extraction. Biglycan, keratan sulfate and hyaluronic acid, uniformly distributed in the periodontal ligament of the unextracted sides, showed little change after the extraction. These results demonstrate that occlusal hypofunction causes tissue remodeling of the periodontal ligament, with a significant decrease of chondroitin sulfate, decorin and heparan sulfate.

Animals↗
PubMed1998

A comparison of in vivo gene delivery methods for antisense therapy in ligament healing.

To determine the most efficient in vivo delivery method of oligonucleotides for antisense therapy in ligament healing, fluorescence-labelled phosphorothioate oligodeoxynuleotides (ODN) were introduced into 12 rabbit ligament scars 2 weeks after injury using haemagglutinating virus of Japan (Sendai virus: HVJ)-conjugated liposomes. We compared the efficiency of cellular uptake of fluorescence as a percentage of all cells in each scar using three delivery procedures: (1) direct free-hand injection into the ligament scar using a conventional syringe; (2) systematic direct sca injection using a repeating 10 microliters dispenser and a square mesh grid system; and (3) injection into the feeding (femoral) artery. Results showed that there was a significant difference in fluorescence uptake by scar cells on day 1 after injection between the three delivery methods: (1) direct free-hand, 9.7 +/- 7.6% (average +/- s.d.); (2) systematic direct, 58.4 +/- 15.9%; and (3) intra-arterial, 0.2 +/- 0.1%. Systematic direct injection was most efficient and it resulted in 25.9 +/- 13.0% of scar cells being labeled at 7 days after transfection. We then introduced antisense ODN for the rabbit proteoglycan, decorin, into ligament scars with this delivery method and confirmed a significant inhibition of decorin mRNA expression in antisense-treated scar tissues in vivo both at 2 days (42.3 +/- 14.7% of sense control +/- s.d.; P < 0.0025) and 3 weeks (60.5 +/- 28.2% of sense control +/- s.d.; P < 0.024) after treatment, compared with sense ODN-treated scars. Decorin was significantly suppressed also at protein level in antisense-treated scars at 4 weeks (66.6 +/- 35.7% of sense control +/- s.d.; P < 0.045) after treatment. These results demonstrate that in vivo transfection efficiency in ligament scars is 'delivery system dependent' and that introduction of antisense ODN for the small proteoglycan, decorin, with this delivery method can lead to significant suppression of its expression over 3 weeks both at mRNA and protein levels. Thus, an effective model for the potential manipulation of scar composition and quality in ligament healing has been established.

Animals↗
PubMed1984

Elastin mRNA levels during foetal development of sheep nuchal ligament and lung. Hybridization to complementary and cloned DNA.

Elastin mRNA levels were quantified in sheep nuchal ligament and lung during the latter half of foetal development with elastin-specific cDNA (complementary DNA) probes using both hybridization in solution (saturation analysis) and hybridization on a fixed support (Northern analysis). For the solution-hybridization studies, cDNA prepared from nuchal-ligament mRNA was enriched to 65% for elastin sequences by hybridizing it to its template at a R0t (mol X s X litre-1) value that included only the abundant class of mRNA sequences. Hybridization of this probe to RNA extracted from nuchal ligament between 70 and 138 days after conception demonstrated elastin sequences increased about 10-fold (from 0.047 to 0.438% of total RNA). In contrast, lung elastin mRNA levels increased only 3-fold (from 0.009 to 0.022% of total RNA) during the same period. Over this development period these values correspond to increases in the average number of elastin mRNA molecules from 950 to 20 000 molecules/ligament cell and from 130 to 330 molecules/lung cell. For Northern analysis, elastin mRNA was purified from near-term-sheep nuchal ligament on sucrose density gradients. Analysis of the translation products of this elastin mRNA showed that relative elastin precursor synthesis was at least 80% of total [3H]valine incorporation. The Mr of this elastin mRNA, determined by methylmercury-agarose-gel electrophoresis, was approx. 1.25 X 10(6). Northern hybridization of nuchal ligament and lung RNA to a [32P]cDNA probe, transcribed from this sucrose-gradient-purified elastin mRNA, confirmed the developmental changes in elastin mRNA levels detected by solution-hybridization techniques. The specificity of this method was confirmed by using a cloned elastin gene fragment. These studies demonstrate that elastin mRNA levels in organs such as nuchal ligament and lung increase with foetal development, but that there are significant differences in the average cellular elastin mRNA content of these two organs.

Animals↗
PubMed2002

Tendon healing in a bone tunnel. Part II: Histologic analysis after biodegradable interference fit fixation in a model of anterior cruciate ligament reconstruction in sheep.

PURPOSE: Tendon-to-bone healing of soft-tissue grafts has been described to progress by the development of a fibrous interzone that undergoes a maturation process leading to the development of an indirect type of ligament insertion. Previous studies used extra-articular models or fixation far away from the joint line; thus, no data are available investigating tendon-to-bone healing of a soft-tissue graft fixed anatomically. Therefore, we studied the tendon-to-bone healing of the anatomic soft-tissue graft interference fit fixation in a model of anterior cruciate ligament (ACL) reconstruction in sheep. TYPE OF STUDY: Animal study. METHODS: Thirty-five mature sheep underwent ACL reconstruction with an autologous Achilles tendon split graft. Grafts were directly fixed with biodegradable poly-(D,L-lactide) interference screws. Animals were euthanized after 6, 9, 12, 24, and 52 weeks and histologic evaluations were performed. Undecalcified specimens were evaluated under normal and polarized light. Additionally, animals received a polychrome sequential labeling (tetracycline, xylenol orange, and calcein green) to determine bone growth per time under fluorescent light. RESULTS: Intratunnel histologic findings at 6 weeks showed a tendon-bone junction with only a partial fibrous interzone between the graft tissue and the surrounding bone. A mature intratunnel tendon-bone junction with a zone of fibrocartilage was found at 9 to 12 weeks. At the tunnel entrance site a wide regular ligamentous insertion site was seen in all specimens after 24 weeks. This insertion showed regular patterns such as the direct type of insertion of a normal ligament with a dense basophilic transition zone consisting of mineralized cartilage. CONCLUSIONS: A fibrous interzone between the graft tissue and the bone tunnel was only partially developed, which is in contrast to all previous studies in which nonanatomic fixation was used. Thus, it is reasonable to assume that the tendon-to-bone healing in the present study may progress partially by direct-contact healing without the development of a fibrous interzone. To our knowledge, this is the first report describing the development of a direct type of ligament insertion after ACL replacement with a soft-tissue graft. This is in contrast to previous studies reporting the development of an indirect type of insertion when using nonanatomic fixation far away from the joint line. Thus, histologic data strongly indicate that anatomic interference fit fixation is beneficial for tendon-to-bone incorporation by leading to the development of a direct type of ligament insertion.

Absorbable Implants↗
PubMedDate not supplied

Arthroscopic repair of dorsal radiocarpal ligament tears.

Various authors have highlighted the importance of the dorsal radiocarpal (DRC) ligament in normal carpal kinematics. It is a secondary stabilizer of the lunate and has a role in midcarpal stability. Disruption of the DRC ligament has been implicated in the development of static VISI and DISI deformities, prompting some authors to perform an open reattachment of the dorsal capsule if there is an associated scapholunate ligament tear. The management of these tears is still evolving. The contribution of a DRC ligament tear to the development of wrist pain remains uncertain when combined with additional wrist pathology. An isolated DRC ligament tear was responsible for chronic dorsal wrist pain in 2 patients. A previously undescribed inside-out repair method of the DRC ligament using a volar wrist portal was successful in relieving the pain. Recognition of this condition and further research into treatment methods is needed.

Adult↗
PubMedDate not supplied

Desmotomy of the accessory ligament of the superficial digital flexor tendon in the horse with use of a tenoscopic approach to the carpal sheath.

OBJECTIVE: To describe a tenoscopic approach to the carpal sheath for desmotomy of the accessory ligament of the superficial digital flexor tendon. STUDY DESIGN: The surgical procedure was developed with use of normal forelimbs from equine cadavers and experimental horses. ANIMALS OR SAMPLE POPULATION: Twelve equine cadaveric forelimbs, 4 forelimbs from 2 horses anesthetized for terminal surgical laboratories, and 10 forelimbs from five experimental horses were used. METHODS: The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal was made approximately 2 cm proximal to the distal radial physis for arthroscope insertion. An instrument portal was made approximately 0.2 cm proximal to the distal radial physis. After flexion of the limb to 90 degrees, the accessory ligament of the superficial digital flexor tendon was palpated and desmotomy was performed. Cadaveric limbs were dissected to confirm complete desmotomy. Experimental horses were monitored for short- (perioperative) and long- (4 weeks) term postoperative complications. RESULTS: A tenoscopic approach to the carpal sheath provided adequate surgical access to the accessory ligament of the superficial digital flexor tendon for desmotomy. Most of the accessory ligament of the superficial digital flexor tendon could be easily seen within the sheath, except for the proximal 2 cm that could be readily palpated and subsequently transected. Important technical considerations were location of the arthroscope portal, adequate sheath distention, limb flexion to 90 degrees, and desmotomy location. It was beneficial, but apparently not essential, to avoid the proximal perforating vessel. Postoperatively, some horses had swelling but were not lame and had normal range of motion of the carpus. CONCLUSIONS: Desmotomy of the accessory ligament of the superficial digital flexor tendon could be performed by using a lateral tenoscopic approach to the carpal sheath. CLINICAL RELEVANCE: Desmotomy of the accessory ligament of the superficial digital flexor tendon by using a tenoscopic approach to the carpal sheath is an alternative technique to the medial incisional approach.

Animals↗
PubMed2000

The proximal ligamentous component of the triangular fibrocartilage complex.

The proximal ligamentous component of the triangular fibrocartilage complex (TFCC) was studied anatomically using 15 fresh-frozen cadaver hand forearm specimens. Changes in the length of either side of this component were analysed during forearm rotation with the complete three-dimensional structure of the TFCC preserved. The proximal ligamentous component consists of three portions: dorsal, central and palmar. The dorsal and palmar portions connect the radius and ulna directly. These were recognized in all specimens whereas the central portion was not constant. The morphology of the proximal component was categorized into three types: fan-shaped, V-shaped, and funnel-shaped in five wrists each. Changes in ligament length during forearm rotation were measured using fine wires under slight tension that paralleled the ligaments from origin to insertion. The dorsal and palmar portions demonstrated three trends: the dorsal portion increased in length from supination to pronation whereas the palmar portion increased in length from pronation to supination; the length of the dorsal portion remained almost constant as the palmar portion increased in length from pronation to supination; the length of the palmar portion remained almost constant while the dorsal portion lengthened from supination to pronation. These variations appear to be related to which portion of the ligament was attached nearest to the centre of the ulnar fovea, where the rotational axis of the forearm passes. The portion attaching nearest to the fovea demonstrated a nearly isometric length pattern, whereas the portion which attached at a distance showed greater extensibility. These findings suggest that the proximal component of the TFCC corresponds to a true radioulnar ligament, and the isometric and eccentric fibres act mutually during forearm rotation.

Cadaver↗
PubMed2002

Treatment of "Gamekeeper's Thumb" by reconstruction of the ulnar collateral ligament.

This study examines the treatment of 22 thumbs with symptomatic laxity of the ulnar collateral ligament of the metacarpophalangeal joint by ligament reconstruction 1 week to 10 years after injury. The existing ligament remnants were repaired in 13 thumbs and were re-attached to bone, using a bone anchor, in seven cases. Two ligaments were reconstructed using the extensor pollicis brevis tendon. Patients were reviewed at a mean of 16 months. Functional stability was regained in all patients, but two thumbs had ongoing pain in the metacarpophalangeal joint. All but one patient returned to their original work and recreational pastimes. This study suggests that ligament reconstruction for chronic laxity of the ulnar collateral ligament is likely to achieve painless stability of the metacarpophalangeal joint even when reconstruction is delayed. This makes joint fusion unnecessary in most instances.

Adolescent↗
PubMed2001

[Modified collateral ligament reconstruction with the tendon of the abductor pollicis tendon in treatment of chronic radial instability of the basal thumb joint].

Injuries to the radial collateral ligament of the MP joint of the thumb occur much less frequently than injuries to the ulnar collateral ligament. Ligament injury is usually a result of direct trauma. The resultant instability to the thumb usually impairs hand function. In acute lesions to the radial collateral ligament, direct repair is often possible. In cases of chronic radial joint instability, secondary ligament reconstruction with a free tendon graft, most commonly the palmaris longus tendon, is usually recommended. We describe another technique using the tendon insertion of the abductor pollicis brevis muscle. The tendon inserting distally can be used as a stable ligament after dividing it at the border to the muscle and attaching it to the head of the metacarpal bone with a wire. The follow-up for six patients treated by this method showed good and painless stability and function of the thumb in a time span of one year.

Chronic Disease↗
PubMed2001

[Arthroscopic diagnosis of concomitant scapholunate ligament injuries in fractures of the distal radius].

To investigate the occurrence of carpal ligamentous injuries in patients with fractures of the distal radius, the results of 122 wrist arthroscopies were analysed within a retrospective study. Indications for arthroscopy included suspected carpal instability according to radiographic findings and/or the necessity for internal fixation of the radius fracture. Arthroscopy revealed acute scapholunate ligament tears in 84 patients. Scapholunate separation was found to be of prognostic value for ligament tears. There was no association between ligamentous lesions and carpal angles or fracture dislocation. Scapholunate ligament tears were most frequent in sagittal articular fractures. In these cases, wrist arthroscopy should be performed during operative treatment of the radius fracture to allow direct visualization and subsequent repair of ligamentous tears.

Adolescent↗
PubMed2002

[Scapholunate ligament tears in MR arthrography compared with wrist arthroscopy].

In a blinded study from January to July 2000, 125 patients suffering from specific complaints of the wrist were prospectively examined with direct MR arthrography. Within 24 hours an arthroscopy of the wrist was performed. With MR arthrography in 21 patients or 17 % of all patients, injury of the scapho-lunate ligament was diagnosed. In all patients this could be verified arthroscopically. In the remaining 104 patients, no SL-ligament lesions were diagnosed with the MR arthrography. However, partial lesions were found via arthroscopy in seven cases and complete lesions of the ligament were found in one case, where MRI findings expected an intact SL ligament. In the remaining 96 cases, the MRI could correctly exclude a lesion of the SL-ligament. The diagnosis of a SL-ligament lesion by means of MRI was correct in 100 % of the cases (specificity), the exclusion of such lesions in 72 % (sensitivity). Positive or negative predictive values of 100 % or 92 % were achieved. Since a sensitivity of 100 % cannot be reached at the moment, MR arthrography cannot replace arthroscopy. However, it could be a potent additional tool for wrist diagnosis if intraarticular contrast is used. It can facilitate the diagnostics and the indication for surgery of the wrist and help to reduce arthroscopic interventions for purely diagnostic purposes and without any therapeutic consequences. With improvement of the technique of magnet resonance tomography we can expect a further increase of accuracy in the clinical use of the MR arthrography in the diagnostic workup of the wrist.

Adult↗
PubMed1993

Knee laxity and function after conservative treatment of anterior cruciate ligament injuries. A prospective study.

Knee laxity and function were investigated in a prospective study including 40 patients with acute anterior cruciate ligament injury and 11 patients with minor knee injury not involving the cruciate ligaments (controls). None of the patients had primary ligament repair. Instrumental testing (OSI, Hayward, California) of the static laxity of both knees was performed at one, three, six, and 12 months after the injury. The initial laxity of the anterior cruciate-deficient knees was greater than that of the controls. At 12 months the laxity at 180N tibial load for the patients with anterior cruciate ligament injury exceeded the laxity found within one month of injury. At 12 months half of these patients complained of symptoms of instability and one out of four patients had had severe subluxations with accompanying haemarthrosis. Patients with combined anterior cruciate and medial collateral ligament injury had the greatest initial laxity and the worst outcome. In all, 20% of the patients were scheduled for reconstruction of the anterior cruciate ligament during the observation period.

Adolescent↗
PubMedDate not supplied

[Function of the glenohumeral ligaments in active protection of shoulder stability].

UNLABELLED: We harvested the joint capsule, the glenohumeral ligaments, and the coracohumeral ligaments of 8 fresh formalin-preserved shoulder specimen. We made use of the van Gieson technique and a special silver impregnation for staining peripheral axons according to Nowotny. The ligaments were cut into slices with a thickness of 15 microns. In total we performed 10,000 cuts. We discovered axons in all ligaments. These axons had no relation to vessels or vessel walls. Besides these axonal structures we detected type II mechanoreceptors (Pacini receptor). CLINICAL SIGNIFICANCE: The neural structures discovered in the glenohumeral capsule are of clinical importance especially in consideration of the high account of recurrent shoulder dislocation and concomitant Bankart lesions. Receptors located in the glenohumeral ligaments might control the stabilizing shoulder musculature. On this premises, rupture or detachment of these ligaments will lead to a loss of the feedback mechanism.

Adult↗
PubMed1989

[Ligament lesions of the knee joint in childhood].

As a matter of principle, all lesions of the knee associated with haemarthrosis must be examined for internal injuries. Ligament ruptures are rare; usually, there are bony ligament tears that show up on x-ray film. Examination of ligament stability in children is useful only if the x-ray is negative and after the knee joint has been punctured under anaesthesia, and can be justified only in that case. Diagnosis is possible only by means of x-ray films taken in forced extreme joint position in two planes, with lateral comparison. Treatment of all non-dislocated ligament tears is conservative; slight dislocations can be tolerated in cruciate and capsular ligaments, since the epiphyseal cartilage is not affected. Surgery should be performed only if tears are considerably dislocated. Proximal tears of collateral ligaments are epiphyseal fractures that can be treated conservatively only if there is no dislocation; if they are dislocated, surgery is absolutely mandatory.

Child↗
PubMedDate not supplied

[Effect of the Hoffa fat pad on revascularization of the ruptured anterior cruciate ligament. A histologic study of the rabbit model].

After intersection of anterior cruciate ligament both ends were stitched together again. In group A the ligament was surrounded by a flap of fat pad, whereas in control group B the intersected ligament just was sutured. Postoperative the leg was immobilised by cast from 4 to 8 weeks. After that time intraarterial injection by Romeis method was performed, the bone-ligament-bone block was fixed in paraffine and the histological investigation followed. All ligament blocks of group A (n12) showed an intact anterior cruciate surrounded by well vascularized soft tissue which has been transformed from the fat pad. Ligaments of group B did not heal and where regressive changed.

Adipose Tissue↗
PubMedDate not supplied

[Management of long-standing instabilities of the knee ligaments].

Since 1975, a total of 1015 knee ligament grafts have been carried out in the orthopedic department of the St. Elisabeth-Klinik in Saarlouis. Proceeding from the method of extra-articular stabilization that was taken over and modified by Mittelmeier, the authors initially favored Ellison's method of lateral ligament displacement, supplementing the operation by diverting the nerve tract. Although the results of surgery were not bad, the importance of rotational instability led the authors increasingly to turn to intra-articular stabilization. Today, the most commonly used methods for frontal instability are those modified by Brückner or Glency, both with good results. With regard to ligament prostheses, the authors tend to be more cautious. Certainly, the alloplastic artificial ligament replacement is an important advance in the case of certain indications, but is probably only a further element of future developments. Many of the problems encountered by Fritz Lange with his first, silk plastic ligament replacement, described by Max Lange in the 1960s, are still applicable today. Here one could mention in particular the surgeon's misgivings concerning indication and the cautious estimates of the changes of success of plastic surgery of the ligaments.

Athletic Injuries↗
PubMedDate not supplied

Re-formation of the coracoacromial ligament after open resection or arthroscopic release.

In 21 (91%) of 23 shoulder revisions after primary surgery involving resection or release of the coracoacromial ligament, there was evidence of a reattached or re-formed coracoacromial ligament. In 9 cases there was no other obvious explanation for symptom recurrence, and in 7 cases the coracoacromial ligament might have influenced progression of rotator cuff pathosis. Electron micrographs of a re-formed ligament showed a substantially large amount of large-diameter (> 100 microns) collagen fibrils resembling those of a normal ligament. We conclude that the coracoacromial ligament has an ability to re-form or reattach, whether primarily resected or released, and that this might account for recurrent symptoms.

Adult↗