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PubMedDate not supplied

Adult acquired flatfoot deformity at the talonavicular joint: reconstruction of the spring ligament in an in vitro model.

The mobile unilateral flatfoot deformity of chronic posterior tibial tendon insufficiency has been difficult to correct by soft tissue procedures. The procedures can decrease pain, but they do not always correct the longitudinal arch or relieve all the symptoms. Using 10 fresh frozen cadaveric specimens and a rig for stimulation of weightbearing, the deformity associated with chronic posterior tibial tendon insufficiency was produced by multiple ligamentous release and documented by AP and lateral radiographs. Reconstruction of the spring ligament using a ligament bone autograft from the superficial deltoid ligament was then performed and tested under load. The mean correction was within 2.5 degrees of normal (over or undercorrection) on both the AP and lateral radiographs with the specimens under load. Clinical Relevance. In posterior tibial tendon insufficiency, it may be possible to address the ligament as well as tendon insufficiency to gain a corrected arch. The success of such a procedure will depend upon adequate tendon and ligament reconstruction in a fully mobile deformity. Questions remain as to the adequacy of this ligament graft, and a stronger free ligament graft, as well as correction of any bony malalignment, may be required.

Ankle Joint↗
PubMed1998

The medial collateral ligaments of the human ankle joint: anatomical variations.

This study aimed to investigate anatomical variations within the medial collateral ligament complex of the human ankle joint. Osteoligamentous preparations of 40 ankles from 20 cadavers were studied. Six different component bands of the medial collateral ligament complex were observed: four superficial bands (tibiospring, tibionavicular, superficial posterior tibiotalar, and tibiocalcaneal ligaments), of which only the tibiospring and tibionavicular ligaments were constant, and two deep bands (deep posterior tibiotalar and deep anterior tibiotalar ligaments), of which only the deep posterior tibiotalar ligament was constant. No pattern was observed in the distribution of additional bands. A consistent and universally accepted system for naming the various bands of the medial collateral ligament is necessary to enable easy and accurate comparisons between studies. We suggest that this system should be based on the attachments of the ligaments.

Aged↗
PubMed2004

The accessory atlantoaxial ligament.

OBJECTIVE: The stability of the joints connecting the cranium to the upper cervical spine is of vital importance. The ligaments of this region, for the most part, have been thoroughly investigated, with the exception of the accessory atlantoaxial ligament. METHODS: Ten cadaveric specimens were examined to observe the anatomy of this ligament. RESULTS: This ligament was found in all specimens, and in each, it not only connected the atlas to the axis but also continued cephalically to the occipital bone. The approximate dimensions of this structure were 3 cm x 5 mm. Functionally, this ligament became maximally taut with a rotation of the head of 5 to 8 degrees. Laxity was observed with cervical extension, and maximal tautness was seen at 5 to 10 degrees of cervical flexion. CONCLUSION: The accessory atlantoaxial ligament seems to participate in craniocervical stability and perhaps should be renamed the accessory alar ligament or accessory atlantoaxialoccipital ligament; both of these terms better denote its anatomic characteristics. Perhaps in the future, better magnetic resonance imaging techniques and machines will be able to identify this structure so as to appreciate its integrity after upper cervical spine trauma.

Aged↗
PubMed1984

Advances in the understanding of knee ligament injury, repair, and rehabilitation.

Knee injuries continue to present a complex set of clinical problems. The answers to these problems have recently been redefined by the application of sophisticated biomechanical research methods to the study of knee ligaments and joint function. This manuscript reviews contributions which our laboratory has made to the understanding of knee injury, highlighting those research findings which form the basis for our clinical treatment of knee ligament injuries. High strain-rate techniques for studying knee ligament failure have replaced the previous low strain-rate methods and distinguish the failure mechanism of ligaments from that of bone. Ligament function is now further defined by measuring the restraining force provided by specific ligaments, adding to the information provided by cutting studies. The development of the 6-degrees-of-freedom concept and the instrumented kinematic chain now permit precise analysis of joint position, motion, and laxity. Biomechanical evaluation of intra-articular anterior cruciate ligament substitution has emphasized the importance of selection of a high-strength graft material, meticulous surgical technique with attention to graft vascularity, precise location of graft fixation sites, judicious adjustment of graft tension, post-operative protection during tissue remodelling, and a carefully conceived rehabilitation program. Newer biomechanical research methods have provided a sound scientific foundation on which to base clinical decisions concerning the care of knee ligament injuries.

Adrenal Cortex Hormones↗
PubMed1991

The effect of continuous passive motion on knee ligament reconstruction with carbon fibre. An experimental investigation.

Our purpose was to determine whether continuous passive motion enhanced the quality of knee ligament reconstruction using carbon fibre. In 46 rabbits the medial collateral ligaments were excised and replaced with carbon fibre prostheses. The animals were treated postoperatively by either continuous passive motion, cast immobilisation or cage activity, termed intermittent active motion. At six weeks, the ligaments were compared histologically and biomechanically with normal (control) medial collateral ligaments and with sham-operated controls. The ligaments treated with continuous passive motion were superior to those in the other two treatment groups. There were no ligament failures in any of the groups. This study suggests that continuous passive motion, initiated immediately postoperatively, enhances the biomechanical properties of carbon fibre ligament replacement of the medial collateral ligament while preventing the harmful effects of joint immobilisation.

Animals↗
PubMed1998

Subtalar arthrography in acute injuries of the calcaneofibular ligament.

We treated 43 acute tears of the calcaneofibular ligament by operation in 43 patients after subtalar arthrography. There were 22 men and 21 women with a mean age of 22.3 years (14 to 61). Anteroposterior (AP), lateral and oblique views were obtained with the foot in 45 degrees of internal rotation and the ankle in the neutral position. Any communication or leakage to the ankle, tendon sheaths, subcutaneous tissue and sinus tarsi was recorded. We examined an oblique view of the microrecess along the interosseous ligament and an AP view of the lateral recess just under the distal end of the fibula. We also studied a control group of 27 patients with isolated injuries of the anterior talofibular ligament without rupture of the calcaneofibular ligament. The findings in the two groups were significantly different when examined for leakage to the ankle (p=0.0002), to the peroneal tendon sheaths (p=0.0347) and to the subcutaneous tissue (p=0.0222), absence of the microrecess (p=0.0055) and presence of the lateral recess (p=0.0012). Many ankle sprains which involve tearing of the calcaneofibular ligament are accompanied by injuries of the subtalar joint. Combined injuries of the anterior talofibular ligament and calcaneofibular ligament, and isolated injury of the anterior talofibular ligament should be differentiated.

Adolescent↗
PubMed1993

The existence and distribution of melanocytes in the periodontal ligament of the mongrel dog.

The existence and distribution of melanocytes in the periodontal ligament of the mongrel dog were investigated. Melanocytes were found in the periodontal ligament of the maxillary incisor and premolar segments. Melanocytes in the periodontal ligament varied in number, and generally appeared as dendritic or elongated cells with several, long cytoplasmic processes. These melanocytes were always distributed closer to the tooth root side of the periodontal ligament than the alveolar bone side, but did not contact the cementum. Melanocytes were longitudinally distributed in the apical half of the periodontal ligament. There were no findings suggestive of a relationship between melanocytes and epithelial rests of Malassez or other cellular elements of the periodontal ligament. Although some parts of the gingival mucosa of all dogs in this study showed pigmentation, no relationship was seen between melanocytes in the periodontal ligament and those in the gingival mucosa. This is the first report of melanocytes in the periodontal ligament under normal conditions.

Animals↗
PubMed1998

The load applied to the foot in a patellar ligament-bearing cast.

The purpose of this study was to determine whether a patellar ligament-bearing cast reduces the load applied to a foot in a cast. In a study of ten people who had no history of gait abnormalities, disease involving the motor system, or deformities of the lower extremities, we compared the load applied to the plantar aspect of a foot in a cast (as detected with F-Scan computer-monitored pedobarographic sensors) with the total load that an extremity in a cast receives relative to the ground (as detected with force-plates). Six trials were completed three times by each person. The trials consisted of walking (1) while wearing regular shoes; (2) with a patellar ligament-bearing cast on one leg; (3) with a patellar ligament-bearing cast and an overlying soft knee brace, locked in full extension, on the leg; (4) with only a below-the-knee cast on the leg; (5) with a below-the-knee cast and an overlying knee brace, locked in full extension, on the leg; and (6) with only a knee brace, locked in full extension, on the leg. The loads at peak heel-strike for all three trials were averaged and normalized to body weight. The load on the plantar aspect of the foot, as compared with the total load, was reduced a mean of 11 percent when the patellar ligament-bearing cast was worn alone, and it was reduced a mean of 26 percent when the patellar ligament-bearing cast was used with an overlying knee brace locked in full extension. This difference was significant (p = 0.007). With the numbers available, we could not detect a significant difference between the reduction in load when a patellar ligament-bearing cast was worn alone compared with that when a below-the-knee cast was worn alone or between the reduction when a below-the-knee cast was worn alone compared with that when a below-the-knee cast was used with a knee brace (p = 0.3). In conclusion, we could not demonstrate a significant reduction in the load on the foot when a patellar ligament-bearing cast was used in a traditional fashion; however, a significant (p = 0.007) reduction in load was found when a knee brace locked in full extension was worn in addition to the patellar ligament-bearing cast.

Adult↗
PubMed2002

Enhancement of tendon-bone integration of anterior cruciate ligament grafts with bone morphogenetic protein-2 gene transfer: a histological and biomechanical study.

BACKGROUND: The integration of tendon grafts used for replacement of the anterior cruciate ligament is still sometimes unsatisfactory and may be associated with postoperative anterior-posterior laxity. The goal of this study was to examine the capacity of bone morphogenetic protein-2 (BMP-2) gene transfer to improve the integration of semitendinosus tendon grafts at the tendon-bone interface after reconstruction of the anterior cruciate ligament in rabbits. METHODS: The anterior cruciate ligaments of adult New Zealand White rabbits were replaced with autologous double-bundle semitendinosus tendon grafts. The semitendinosus tendon grafts had been infected in vitro with adenovirus-luciferase, adenovirus-LacZ (AdLacZ), or adenovirus-BMP-2 (AdBMP-2); untreated grafts served as controls. The grafts were examined histologically at two, four, six, and eight weeks after surgery. In additional experiments, the structural properties of the femur-anterior cruciate ligament graft-tibia complexes, from animals killed eight weeks postoperatively, were determined from uniaxial tests. The stiffness (N/mm) and ultimate load to failure (N) were determined from the resulting load-elongation curves. RESULTS: Genetically engineered semitendinosus tendon grafts expressed reporter genes as well as BMP-2 in vitro. The AdLacZ-infected grafts showed two different histological patterns of transduction. Intra-articularly, infected cells were mostly aligned along the surface, and they decreased in number between two and eight weeks after surgery. In the intra-tunnel portions of the grafts, the number of infected cells did not decrease during the observation period. Moreover, a high number of transduced cells was found in the deeper layers of the tendons. In the control group, granulation-type tissue at the tendon-bone interface showed progressive reorganization into a dense connective tissue, and a later establishment of fibers resembling Sharpey fibers. In the specimens with an AdBMP-2-infected anterior cruciate ligament graft, a broad zone of newly formed matrix resembling chondro-osteoid had formed at the tendon-bone interface at four weeks after surgery. This area was increased at six weeks, showing a transition from bone to mineralized cartilage and nonmineralized fibrocartilage. In addition, in the AdBMP-2-treated specimens, the tendon-bone interface in the osseous tunnel was similar to that of a normal anterior cruciate ligament insertion. The stiffness (29.0 +/- 7.1 N/mm compared with 16.7 +/- 8.3 N/mm) and the ultimate load to failure (108.8 +/- 50.8 N compared with 45.0 +/- 18.0 N) were significantly enhanced in the specimens with an AdBMP-2-transduced graft when compared with the control values (p < 0.05). CONCLUSION: This study demonstrates that BMP-2 gene transfer significantly improves the integration of semitendinosus tendon grafts in bone tunnels after reconstruction of the anterior cruciate ligament in rabbits. CLINICAL RELEVANCE: Novel technologies including gene therapy and tissue engineering, such as those described in this study, may provide useful therapeutic procedures to enhance biological healing after reconstruction of the anterior cruciate ligament.

Animals↗
PubMed1987

Fluoroscopic identification of torn intercarpal ligaments after injection of contrast material.

Wrist arthrography is often used to evaluate the integrity of the scapholunate and lunotriquetral ligaments. This may be difficult when the ligaments are obscured by contrast material in standard radiographic projections, despite filming under fluoroscopic observation during the injection of contrast material. When superimposition occurs, we recommend fluoroscopic positioning of the wrist to optimally visualize the individual ligaments in profile. We applied this technique in performing 240 wrist arthrograms, 88 (37%) of which had scapholunate and/or lunotriquetral ligament tears. As a result, a definite diagnosis of the specific site of ligamentous disruption was possible in all but one case. Using this technique, we also identified six short-segment or "pinhole" ligamentous tears. Identification of commonly interrupted ligaments in profile by using fluoroscopy after contrast material has been injected may allow identification of specific ligamentous disruptions or short-segment tears, as well as a diagnosis of a specific anatomic abnormality that otherwise would not be possible.

Arthrography↗
PubMed1989

[Experimental study of periodontal tissue regeneration. Changes in the periodontium after tooth implantation with and without periodontal ligament].

The role of the periodontal ligament in periodontal tissue regeneration was evaluated. The materials included bilateral upper 1st premolars and lower 2nd, 3rd, and 4th premolars of 11 adult Beagle dogs, aged from 3 to 6 years. Before implantation, the right teeth were extracted and kept for a period of more than 3 months in "a solution for reserving teeth". The left teeth on the other hand, were extracted and soon implanted thus retaining the periodontal ligament into the newly created bone cavities prepared in the right edentulous areas. At the same time, the right reserved teeth were implanted into the left tooth sockets. Implanted teeth were periodically observed macroscopically, radiographically, and histologically for a 6-month period. Macroscopical observation showed good clinical repair in the bilateral sides of the tooth implantation with and without a periodontal ligament. After a 6-week experimental period, radiographic observations of the implanted lower right teeth having a periodontal ligament revealed lamina dura-like findings. Histopathological investigation revealed ankylosis and root resorption on the left side, where the reserved teeth without a periodontal ligament were implanted. But regeneration of the periodontal tissue complex, which consisted of the gingiva, alveolar bone, cementum, and periodontal ligament, was generally observed in the implanted right teeth having a periodontal ligament. These results suggest that the periodontal ligament cells play a significant role in periodontal tissue regeneration.

Animals↗
PubMed2002

Ultrasonographic and histologic evaluation of medial and middle patellar ligaments in exercised horses following injection with ethanolamine oleate and 2% iodine in almond oil.

OBJECTIVE: To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. ANIMALS: 10 healthy horses. PROCEDURE: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO and EO and prior to euthanasia to determine cross-sectional area and evaluate fiber pattern. The patellar ligaments were harvested 2 weeks after injection and examined histologically to evaluate the inflammatory response, fibroplasia, and chondroid metaplasia. RESULTS: Injection of the patellar ligaments with IAO resulted in a greater increase in cross-sectional area on ultrasonography than EO. Both agents caused a decrease in echogenicity of the ligament. Histologically, significantly greater infiltration of inflammatory cells and fibroplasia developed after injection with IAO, compared with EO. Both agents resulted in significantly greater fibroplasia relative to control specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of the medial and middle patellar ligaments with IAO induces more severe inflammation and fibroplasia than EO. Maturation of the inflammatory and fibrous response may contribute to resolution or attenuation of upward fixation of the patella by subsequent stiffening of the ligaments.

Animals↗
PubMed2004

Determination of passive mechanical properties of the superficial and deep digital flexor muscle-ligament-tendon complexes in the forelimbs of horses.

OBJECTIVE: To determine the relative contributions of the muscles, tendons, and accessory ligaments to the passive force-length properties of the superficial (SDF) and deep digital flexor (DDF) myotendinous complexes. SAMPLE POPULATION: 8 cadaveric forelimbs from 6 adult Thoroughbreds. PROCEDURE: In vitro, limb configurations during slack position and myotendinous lengths during subsequent axial loading of forelimbs were recorded before and after transection of accessory ligaments. Expressions were derived to describe the force-length behavior of each muscle, tendon, and accessory ligament-tendon unit; linear stiffness was computed for these components. The elastic modulus was established for the SDF and DDF tendons. RESULTS; Linear stiffness was 2.80 +/- 0.38 kN/cm for the SDF muscle, 3.47 +/- 0.66 kN/cm for the DDF muscle, 2.73 +/- 0.18 kN/cm for the SDF tendon, 3.22 +/- 0.20 kN/cm for the DDF tendon, 6.46 +/- 0.85 kN/cm for the SDF accessory ligament, 1.93 +/- 0.11 kN/cm for the SDF accessory ligament-tendon unit, and 2.47 +/- 0.11 kN/cm for the DDF accessory ligament-tendon unit. The elastic modulus for the SDF and DDF tendons was 920 +/- 77 and 843 +/- 56 MPa, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Both the muscle-tendon and ligament-tendon portions of SDF and DDF myotendinous complexes had important roles in supporting the forelimb of horses. Although muscle tension can be enhanced by elbow joint flexion and active contraction, the accessory ligaments transmitted more force to the distal tendons than did the muscles under the conditions tested.

Animals↗
PubMed2002

The lateral collateral ligament complex and related muscles act as a dynamic stabilizer as well as a static supporting structure at the elbow joint: an anatomical and experimental study.

Among 71 osteoligamentous elbow joint specimens from Japanese subjects, 66% of the lateral ulnar collateral ligaments (LUCLs) were in an incomplete form, such as a fibrous intermuscular septum lying between the anconeus, supinator and extensors, and terminated on the annular ligament. The 'typical' complete ligament, extending from the lateral epicondyle and over the radial collateral ligament (RCL) to the crista spinatoris, appeared in only 20% of the elbows examined. This observation suggests that, in Japanese subjects, the LUCL is not usually a simple ligamentous static stabilizer, but acts as a dynamic stabilizer, together with its related muscles. In addition, when the elbow was flexed by more than 90 degrees, the distance between the lateral epicondyle and the radial head became almost 1.5 mm larger than the distance from the epicondyle to the annular ligament. We therefore consider that, in the overflexed position, the radial head moves slightly distal while the length of the RCL remains almost constant. This morphometrical observation suggests that the annular ligament needs to be supported by the LUCL-muscle complex from the distal side, as well as by the RCL from the proximal side. This extended definition of the lateral collateral ligament complex and its associated muscular function is discussed.

Aged↗
PubMed1982

Mobility of the ankle joint: recording of rotatory movements in the talocrural joint in vitro with and without the lateral collateral ligaments of the ankle.

A method for graphic recording of rotatory movements in osteoligamentous ankle preparations is described. By this method it is possible to record characteristic mobility patterns in two planes at the same time. The ankle is affected by a known torque, so that the individual mobility patterns are reproducible with unchanged condition of the ligaments. Six amputated legs were investigated in the sagittal and horizontal planes and another six in the sagittal and frontal planes. Mobility patterns were recorded with intact ligaments and after successive cutting of the lateral collateral ligaments of the ankle in the anteroposterior direction. In the sagittal plane increased dorsiflexion was observed after total cutting of the lateral ligaments, while plantar flexion remained unchanged. In the horizontal plane the internal rotation of the talus increased in step with increasing injury to the ligament, particularly when the ankle was plantar flexed. When all collateral ligaments had been cut, an increase in external rotation occurred, especially in dorsiflexion. In the frontal plane the talar tilt increased gradually with increasing injury to the ligaments. Talar tilt was at a maximum in the neutral position of the ankle or in plantar flexion. After total severing of the collateral ligaments, however, talar tilt was most marked in dorsiflexion of the ankle.

Ankle Joint↗
PubMed1984

Posterior cruciate ligament injuries.

We have studied 48 patients with posterior cruciate ligament injury and 14 knees from fresh frozen cadavers. A diagnosis of posterior cruciate ligament injury was made by the sag and posterior drawer signs and stress x-ray films, the latter being useful in the grossly swollen and multiple ligament-injured knee. For avulsion injury, surgical management gave the best results. Other isolated posterior cruciate ligament injuries did well conservatively. When posterior cruciate injury is part of a multiple ligament injury, the nature of the associated ligament injury and that of the posterior cruciate determine the type of treatment; the posterior cruciate ligament is not more important than other knee ligaments.

Female↗
PubMed1995

Effect of quadriceps or hamstring contraction on the anterior shear force to anterior cruciate ligament failure. An in vivo study in the rat.

We studied the effect of quadriceps or hamstring contractions on the anterior tibial shear load to anterior cruciate ligament failure in an in vivo rat model. In both knees of 20 Wistar rats the joint capsule and ligaments, except the anterior cruciate ligaments, were cut and the menisci resected. In 10 rats the right ligament was loaded to failure by anterior translation of the tibia relative to the femur in a testing device during hamstring contraction induced by electrical stimulation of the ischiatic nerve. In the other 10 rats, the right ligament was loaded to failure correspondingly during quadriceps contraction induced by electrical stimulation of the femoral nerve. The loading rate was 2.5 mm s-1 (approximately 0.6(-1)). The knee flexion during testing was 30 degrees. As control, the anterior cruciate ligament of the left knee was loaded correspondingly with relaxed muscles. The ultimate load for the ACL tested during hamstring contraction was 1.5 times higher than when tested with the hamstrings relaxed, more than double the energy was absorbed at failure and the linear stiffness was 1.2 times higher. During testing with quadriceps contraction, no differences in the structural properties were found, compared to testing with the quadriceps relaxed. Our findings show that hamstring contraction helps to resist anterior tibial shear force at 30 degrees knee flexion in rats thus protecting the anterior cruciate ligaments. Quadriceps contraction in this situation does not affect anterior shear force to ligament failure.

Animals↗
PubMed1999

Sonographic evaluation of the posterior cruciate ligament in amputated specimens and normal subjects.

The purpose of this study was to define the sonographic appearance and echogenicity of the normal posterior cruciate ligament. We examined the posterior cruciate ligament of five amputated specimens and five normal subjects using a 10 MHz linear array transducer. One K-wire was inserted into the substance of the posterior cruciate ligament of the amputated knee specimens to verify the location of the ligament on the sonogram. Various angles of insonation were used to examine the echogenicity of the posterior cruciate ligament. The results showed that the in situ posterior cruciate ligament appeared as a hypoechoic band relative to the surrounding tissue on sonograms, but it appeared hyperechoic when it was isolated and immersed in a water bath. The specific spatial orientation of the posterior cruciate ligament and anisotropy phenomenon contributed to the hypoechogenicity of the posterior cruciate ligament in situ on sonogram.

Adult↗