Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Collateral 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 865 records · Page 48Linked to original sources
PubMed1999

Adhesion strength differential of human ligament fibroblasts to collagen types I and III.

Fibroblasts embedded in the amorphous healing tissue matrix of ligaments migrate into damaged sites during the inflammatory process that precedes the formation of new connective tissue after ligament injury. Cell motility involved in this migration is strongly influenced by cellular adhesion to proteins of the extracellular matrix. The adhesion mechanism of interest in this study is the attachment of fibroblasts from the anterior cruciate and medial collateral ligaments to types I and III collagen, two fibrillar collagens secreted by fibroblasts during tissue repair. Types I and III collagen constitute a major portion of these ligaments and are assembled by fibroblasts into long cable-like fibrils in the extracellular space. In this study, a micropipette aspiration technique was used to measure the force required to separate fibroblasts of the anterior cruciate and medial collateral ligaments from substrates composed of type I or III collagen, each at a concentration of 2 or 5 microg/ml. Approximately 1,200 fibroblasts from the anterior cruciate ligament and 1,600 from the medial collateral ligament were used, and the adhesion force and area of these cells were determined. Fibroblasts from the anterior cruciate ligament exhibited greater adhesion force than did those from the medial collateral ligament for all concentrations of types I and III collagen. In addition, the adhesiveness of fibroblasts from both ligaments was dependent on seeding time for all experimental conditions. To determine the adhesiveness per unit area, defined here as the adhesion strength, the adhesion force was normalized by the adhesion area. At early seeding times (15-45 minutes), fibroblasts from the anterior cruciate ligament exhibited greater adhesion strength on surfaces coated with type-I collagen than did those from the medial collateral ligament. However, for both collagen substrates, adhesion strength for fibroblasts from the anterior cruciate ligament decreased with seeding time whereas that for fibroblasts from the medial collateral ligament remained relatively constant for all seeding periods (15-75 minutes).

Adult↗
PubMedDate not supplied

Articular and ligamentous contributions to the stability of the elbow joint.

This preliminary study of four elbow specimens investigates the relationship of articular geometry and ligamentous structures in providing stability to the elbow joint. A technique is presented that describes the constraining features of varus-valgus and distraction in extension and at 90 degree of elbow flexion. Valgus stability is equally divided among the medial collateral ligament, anterior capsule, and bony articulation in full extension; whereas, at 90 degrees of flexion the contribution of the anterior capsule is assumed by the medial collateral ligament which provides approximately 55% of the stabilizing contribution to valgus stress. Varus stress is noted to be resisted primarily by the anterior capsule (32%) and the joint articulation (55%) with only a small (14%) contribution from the radial collateral ligament. At 90 degrees of flexion, little change is noted in the contribution to the radial collateral ligament (9%), but the anterior capsule offers only 13%, with the remaining stability (75%) arising from the joint articulation. In extension, the soft tissue resistance to distraction is provided minimally by either the radial (5%) or the medial (5%) collateral ligaments, and thus primarily originates from the anterior capsule (85%). At 90 degrees of flexion, however, the capsule offers virtually no resistance to distraction (8%). The radial collateral ligament contributes 10% of the stability, while the medial collateral ligament accounts for 78% of the resistance to distraction in this position. Too few specimens have been studied to form any conclusions for direct clinical applications at this time. However, the technique provides a reliable tool with additional studies for different positions and loading conditions underway. These efforts should disclose useful information that might be applied to the management of chronic elbow instability, radial head or olecranon fracture, the design and implantation of elbow prostheses, or provide a rationale for other reconstructive procedures.

Biomechanical Phenomena↗
PubMed2002

In vitro biomechanical study of rotational stabilizers of the canine elbow joint.

OBJECTIVE: To develop a model for measuring rotary stability of the canine elbow joint and to evaluate the relative contribution of the anconeal process (AN), lateral collateral ligament (LCL), and medial collateral ligament (MCL). SAMPLE POPULATION: 18 forelimbs from 12 canine cadavers. PROCEDURE: Forelimbs were allocated to 3 experimental groups (6 forelimbs/group). Each intact forelimb was placed in extension at an angle of 135 degrees and cycled 50 times from -16 degrees (pronation) to +28 degrees (supination) in a continuous manner at 2.0 Hz. Cycling was repeated following sectioning of the structure of interest (group 1, AN; group 2, LCL; and group 3, MCL). Torque at -12 degrees (pronation) and +18 degrees (supination) was measured for each intact and experimentally sectioned limb. A Student t test was performed to compare torque values obtained from intact verses experimentally sectioned limbs and for comparison with established criteria for differentiation of primary (> or = 33%), secondary (10 to 33%), and tertiary rotational stabilizers (< 10%). RESULTS: In pronation, the AN was the only primary stabilizer (65%). For supination, the LCL was a primary stabilizer (48%), AN was a secondary stabilizer (24%), and MCL was a tertiary stabilizer (7%). CONCLUSIONS AND CLINICAL RELEVANCE: With the elbow joint in extension at an angle of 135 degrees, the AN is a primary rotational stabilizer in pronation, and the LCL is a primary stabilizer in supination. Disruption of the AN or LCL may affect rotary range of motion or compromise stability of the elbow joint in dogs.

Animals↗
PubMed2001

The effect of forearm rotation on laxity and stability of the elbow.

OBJECTIVE: The purpose of this study was to quantify the relationship between forearm rotation and valgus/varus laxity of the elbow joint over the range of elbow flexion. BACKGROUND: There is little known about the influence of forearm rotation on the laxity and stability of the elbow joint. The general opinion exists that forearm rotation does not significantly influence the laxity and stability of the elbow joint. METHODS: Nine fresh-frozen cadaver elbows were used. Passive elbow flexion with the forearm in neutral rotation and in 40 degrees and 80 degrees of pronation and supination was performed under valgus/varus loads: (1) in intact elbows; (2) after a lateral surgical approach (lateral epicondylar osteotomy of the distal humerus); (3) after release of the anterior bundle of the medial collateral ligament; and (4) after release of the anterior bundle of the medial collateral ligament plus radial head resection. Valgus/varus elbow laxity was quantified using an electromagnetic tracking device. RESULTS: There was a statistically significant effect (P < 0.05) of forearm rotation on valgus/varus laxity throughout the range of flexion. The laxity was always greater in pronation than in supination, regardless of the surgical approach or the integrity of the anterior bundle of the medial collateral ligament or radial head. CONCLUSIONS: Valgus/varus laxity of the elbow is forearm rotation-dependent. The potential role of this effect should be considered and controlled for in the design of studies examining laxity and stability of the elbow joint. RELEVANCE: The observation that forearm pronation increases valgus/varus laxity, particularly in medial collateral ligament deficient elbows, implies a possible additional factor in throwing kinematics that might put professional baseball pitchers at risk of medial collateral ligament injury due to chronic valgus overload. Our data indicate that forearm rotation should be considered during the clinical examination of elbow instability.

Aged↗
PubMed1987

The role of the posterolateral and cruciate ligaments in the stability of the human knee. A biomechanical study.

Injury to the posterolateral structures of the knee, including the popliteus tendon and arcuate complex, frequently results in poorly understood patterns of instability. To evaluate the static function of these tissues, we used a mechanical testing apparatus that allowed five degrees of freedom to test seventeen specimens from human cadavera at angles of flexion that ranged from zero to 90 degrees. Selective section of the lateral collateral ligament, popliteus-arcuate (deep) ligament complex, anterior cruciate ligament, and posterior cruciate ligament was performed. At all angles of flexion, the lateral collateral ligament and deep ligament complex functioned together as the principal structures preventing varus rotation and external rotation of the tibia, while the posterior cruciate ligament was the principal structure preventing posterior translation. However, at angles of flexion of 30 degrees or less, the amount of posterior translation after section of only the lateral collateral ligament and the deep structures was similar to that noted after isolated section of the posterior cruciate ligament. Isolated section of the posterior cruciate ligament did not affect varus or external rotation of the tibia at any position of flexion of the knee. When the posterior cruciate ligament was sectioned after the lateral collateral ligament and deep ligament complex had been cut, a large increase in posterior translation and varus rotation resulted at all angles of flexion. In addition, at angles of flexion of more than 30 degrees, external rotation of the tibia also increased. The application of internal tibial torque resulted in no increase in tibial rotation after isolated section of the anterior cruciate ligament or combined section of the lateral collateral ligament and deep ligament complex. However, combined section of all three structures increased internal rotation at 30 and 60 degrees of flexion. The increases in external rotation that were produced by section of the lateral collateral ligament and deep ligament complex were not changed by the addition of the section of the anterior cruciate ligament.

Aged↗
PubMedDate not supplied

Role of the medial structures in the intact and anterior cruciate ligament-deficient knee. Limits of motion in the human knee.

We measured motion limits in human cadaveric knees before and after sectioning the anterior cruciate ligament and the medial structures. Sectioning the medial collateral ligament in an anterior cruciate ligament-deficient knee increased the anterior translation limit at 90 degrees of flexion but not at 30 degrees of flexion. The tibia displaced straight anteriorly without exhibiting the coupled internal rotation that occurred in intact and anterior cruciate ligament-deficient knees. A lateral 15 N-m abduction moment produced a coupled external rotation in the medial collateral ligament-deficient knee. This was in marked contrast to intact, anterior cruciate ligament-deficient, or combined medial collateral ligament and anterior cruciate ligament-deficient knees, in which an abduction moment produced a coupled internal rotation. Sectioning only the medial collateral ligament caused a small but significant increase in the abduction rotation limit, whereas larger increases in the abduction rotation limit occurred when the posterior oblique ligament and posterior medial capsule were cut in addition to the medial collateral ligament. Cutting the medial collateral ligament increased the external rotation limit. The increase was independent of whether the anterior cruciate ligament was intact or sectioned. Subsequent cutting of the posterior oblique ligament and posterior medial capsule further increased the external rotation limit.

Adult↗
PubMed1998

MR imaging of knees having isolated and combined ligament injuries.

OBJECTIVE: Although clinical evaluation and MR imaging both accurately reveal injuries in knees with isolated ligament tears, physical examination becomes progressively less reliable when multiple lesions exist. We investigated the accuracy of MR imaging of knees having varying degrees and numbers of ligament injuries. SUBJECTS AND METHODS: We prospectively interpreted the MR images of 340 consecutive injured knees and compared these interpretations with the results of subsequent arthroscopy or open surgery, which served as the gold standard. Our interpretations of MR images focused on five soft-tissue supporting structures (the two cruciate ligaments, the two collateral ligaments, and the patellar tendon) and the two menisci. Patients were divided into three groups: no ligament injuries, single ligament injuries, and multiple ligament injuries. RESULTS: Using MR imaging, we found overall sensitivity and specificity for diagnosing ligament tears to be 94% and 99%, respectively, when no or one ligament was torn and 88% and 84%, respectively, when two or more supporting structures were torn. The difference in specificity was statistically significant (p < .0001). Sensitivity for diagnosing meniscal tears decreased as the number of injured structures increased, but the relationship achieved statistical significance (p = .001) only for the medial meniscus. For all categories of injury, MR imaging was more accurate than clinical evaluation, statistics for which were taken from the orthopedic literature. CONCLUSION: In knees with multiple ligament injuries, the diagnostic specificity of MR imaging for ligament tears decreases, as does the sensitivity for medial meniscal tears.

Adolescent↗
PubMed1994

Elbow instability.

Elbow instability is a spectrum from subluxation to dislocation, with corresponding clinical and pathologic features and therapeutic implications. A classification that unifies these aspects is presented. Posterolateral rotational displacement of the ulna (with the radius) on the humerus appears to be the common mechanism. Acute dislocations can be reduced in supination and tested for valgus stability in pronation. Treatment is determined by the stability following reduction. When there are fractures, the principle is to fix the bones so that the only limitation is the ligaments and then to repair them if the elbow is not stable enough to permit early motion. The three prerequisites for stability of the ulnohumeral articulation are an intact joint surface, anterior medial collateral ligament, and ulnar part of the lateral collateral ligament. Recurrent instability is usually due to insufficiency of the ulnar part of the lateral collateral ligament complex, the lateral ulnar collateral ligament (LUCL), with attenuation of the other secondary soft tissue constraints on the lateral side. Reconstruction of the lateral ulnar collateral ligament typically corrects the problem. Chronic dislocations are treated by similar techniques after releasing contractures and resurfacing the joint with biologic tissue if it is irreversibly damaged.

Biomechanical Phenomena↗
PubMedDate not supplied

The role of the lateral extraarticular restraints in the anterior cruciate ligament-deficient knee.

We measured the increases in tibiofemoral motion when lateral structures were sectioned in anterior cruciate ligament-deficient knees of 20 unembalmed cadaveric whole lower limbs. Motion was measured with a six degrees-of-freedom electrogoniometer. The lateral structures investigated were the iliotibial band and mid-lateral capsule, lateral collateral ligament, and popliteus tendon and the posterolateral capsule. Cutting the anterolateral structures increased anterior translation and internal rotation, particularly in flexion. Increases in motions were highly variable, reflecting the variation in function in the lateral collateral ligament and posterolateral structures. Cutting the lateral collateral ligament produced small changes in anterior translation and external rotation and larger increases in adduction. Cutting the posterolateral structures produced small increases in external rotation. Large increases in external rotation were found only if the lateral collateral ligament was also sectioned. The posterolateral structures act in concert with the lateral collateral ligament in restraining internal and external rotation. External rotation was affected at all flexion angles; internal rotation was affected mainly in extension. Our results can be used in the diagnosis of complex knee ligament injuries. Findings of increased anterior translation in both flexion and extension and increased internal rotation at 90 degrees of flexion are consistent with combined injury to the anterior cruciate ligament and the anterolateral structures. The anterior cruciate ligament-deficient knee with significant posterolateral compromise (posterolateral structures/lateral collateral ligament) would exhibit larger anterior translation in extension than in flexion, increased adduction, and increased external rotation in both flexion and extension.

Adult↗
PubMed1999

Differential expression of integrin subunits in canine knee ligament fibroblasts.

A method for measuring the expression of integrin subunits on the cell surface of knee ligament fibroblasts was developed with use of flow cytometry and immunofluorescence. The ligament cells exhibited uniform size and density, as shown by forward and side-scatter properties, and showed minimal nonspecific binding of isotype control antibodies compared with unstained cells. All cells expressed the alpha5 integrin subunit; lateral collateral ligament cells stained with antibody to alpha5 showed a mean fluorescence intensity 2-fold higher than that of medial collateral ligament cells, 1.5-fold higher than that of posterior cruciate ligament cells, and 3-fold higher than that of anterior cruciate ligament cells, indicating a greater expression of the alpha5 subunit by lateral collateral ligament cells than by medial collateral, posterior cruciate, and anterior cruciate ligament cells. All cells expressed the beta1 integrin subunit; the expression by posterior cruciate ligament cells was 3-fold higher than that by medial collateral ligament or lateral collateral ligament cells and 5-fold higher than that by anterior cruciate ligament cells. All cells expressed the beta3 integrin subunit; the expression by posterior cruciate ligament cells was 1.5, 3, and 4.5-fold greater than that by lateral collateral, anterior cruciate, and medial collateral ligament cells, respectively. Our data suggest there is a differential expression of integrin subunits in knee ligament fibroblasts, and this in part may explain differences in their attachment and adherence to extracellular matrix molecules.

Animals↗
PubMed2001

Volar A1 pulley approach for fixation of avulsion fractures of the base of the proximal phalanx.

Avulsion fractures of the base of the proximal phalanx associated with collateral ligament instability, excluding the thumb, are relatively rare. While the indications for surgical intervention vary, dorsal approaches have been advocated despite the volar location of the fracture fragment and orientation of the collateral ligaments. Ten patients with 11 avulsion fractures at the base of the proximal phalanx associated with collateral ligament instability were treated with open reduction and internal fixation using a volar A1 pulley approach. Anatomic restoration of the articular surface and collateral ligament stability were obtained in all patients. All fractures healed between 5 and 9 weeks (average, 6 weeks). After an average 19.4-month follow-up period all patients had full range of motion of the metacarpophalangeal joint, collateral ligament stability, and grip strength of at least 90% of the uninjured hand. No perioperative complications occurred. The average DASH score at last follow-up examination was 1.8 (range, 0-6). All patients were satisfied with the outcome of surgery. The volar A1 pulley approach is a direct and effective approach for reduction and fixation of avulsion fractures of the base of the proximal phalanx associated with collateral ligament instability.

Adolescent↗
PubMed1985

The posterior cruciate ligament and rotatory knee instability. An experimental study.

The importance of the posterior cruciate ligament in relation to valgus-varus and axial rotatory stability in the knee joint was investigated. Mobility patterns were drawn from 20 osteoligamentous preparations after successive transection of the posterior cruciate ligament (PCL), the medial and lateral collateral ligaments, and the posterior joint capsule. The knee joint remained grossly stable after isolated transection of the PCL, and further cutting of either one of the collateral ligaments or of the posterior capsule yielded no greater instability than one should expect from isolated cutting of each of these structures. The posterior cruciate ligament was the stabilizing factor in flexion and external rotation after injury to the lateral collateral ligament and the posterolateral capsule, and it restricted internal rotation after cutting of the medial cruciate ligament and the posteromedial capsule. Valgus instability was markedly increased during the whole range of movement when PCL was included in injury to the medial compartment ligaments, and when included in a lateral compartment injury a further varus instability was found, though only in the flexed or semiflexed knee. No hyperextension could be demonstrated after these injuries.

Biomechanical Phenomena↗
PubMed1991

Recruitment of knee joint ligaments.

On the basis of earlier reported data on the in vitro kinematics of passive knee-joint motions of four knee specimens, the length changes of ligament fiber bundles were determined by using the points of insertion on the tibia and femur. The kinematic data and the insertions of the ligaments were obtained by using Roentgenstereophotogrammetry. Different fiber bundles of the anterior and posterior cruciate ligaments and the medial and lateral collateral ligaments were identified. On the basis of an assumption for the maximal strain of each ligament fiber bundle during the experiments, the minimal recruitment length and the probability of recruitment were defined and determined. The motions covered the range from extension to 95 degrees flexion and the loading conditions included internal or external moments of 3 Nm and anterior or posterior forces of 30 N. The ligament length and recruitment patterns were found to be consistent for some ligament bundles and less consistent for other ligament bundles. The most posterior bundle of each ligament was recruited in extension and the lower flexion angles, whereas the anterior bundle was recruited for the higher flexion angles. External rotation generally recruited the collateral ligaments, while internal rotation recruited the cruciate ligaments. However, the anterior bundle of the posterior cruciate ligament was recruited with external rotation at the higher flexion angles. At the lower flexion angles, the anterior cruciate and the lateral collateral ligaments were recruited with an anterior force. The recruitment of the posterior cruciate ligament with a posterior force showed that neither its most anterior nor its most posterior bundle was recruited at the lower flexion angles. Hence, the posterior restraint must have been provided by the intermediate fiber bundles, which were not considered in the experiment. At the higher flexion angles, the anterior bundles of the anterior cruciate ligament and the posterior cruciate ligament were found to be recruited with anterior and posterior forces, respectively. The minimal recruitment length and the recruitment probability of ligament fiber bundles are useful parameters for the evaluation of ligament length changes in those experiments where no other method can be used to determine the zero strain lengths, ligament strains and tensions.

Adult↗
PubMed2005

Mechanical properties of the posterolateral structures of the knee.

BACKGROUND: The individual biomechanical strength properties of the fibular collateral ligament, popliteofibular ligament, and popliteus tendon have not been well elucidated by previous studies. To define the necessary strength requirements for a posterolateral knee reconstruction, these properties for the main individual structures of the posterolateral knee need to be defined. HYPOTHESIS: The biomechanical failure properties of the fibular collateral ligament, popliteofibular ligament, and popliteus tendon can be determined by cadaveric testing. STUDY DESIGN: Descriptive laboratory study. METHODS: Each structure was individually isolated in 8 fresh-frozen, nonpaired cadaveric knees and loaded to failure at more than 100%/s. RESULTS: The mean ultimate tensile strength of the fibular collateral ligament was 295 N, the popliteofibular ligament was 298 N, and the popliteus tendon was 700 N. The mean cross-sectional areas of these same structures at their midpoints were 11.9 mm2, 17.1 mm2, and 21.9 mm2, respectively. Although the stiffness of the fibular collateral ligament (33.5 N/m) was similar to that of the popliteofibular ligament (28.6 N/m), the popliteus tendon was significantly stiffer than both (83.7 N/m). CONCLUSION: The popliteofibular ligament, fibular collateral ligament, and popliteus tendon can resist fairly large loads before failure. Knowledge of the strengths of the main native posterolateral knee stabilizers will assist with reconstructive graft choices for these structures.

Adult↗
PubMed1990

Suspension effects on rat femur-medial collateral ligament-tibia unit.

To study the influence of a 2-wk absence of normal weight-bearing forces on dense fibrous connective tissues of growing animals, the geometrical and biomechanical characteristics were examined of femur-medial collateral ligament (MCL)-tibia units (FMT unit) of age-matched controls and tail-suspended young male rats. During the 2-wk suspension, the rate of longitudinal growth of MCL decreased significantly, but no differences were found in the cross-sectional area of the MCL of the two groups. The tensile stiffness of suspension FMT units was significantly less than control, and the proportional, maximum, and failure loads of FMT units were also significantly less for the suspended animals. The stresses in the suspension MCL at the proportional limit were significantly less than control values. These results indicated that a 2-wk absence of normal weight-bearing forces adversely affected the rate of longitudinal growth of MCL and the mechanical properties of the rat FMT unit.

Animals↗
PubMed1994

Effects of different levels of direct current on early ligament healing in a rat model.

Electrical stimulation has been shown to enhance the repair of biological tissues such as bone and tendon. The objective of this study was to determine whether low level direct current enhances the early healing of injured medial collateral ligaments. Eighty-seven rats were divided into three groups on the basis of the level of current delivered. All underwent transection of the medial collateral ligament bilaterally. The experimental medial collateral ligaments received current (which varied by group), while the contralateral medial collateral ligaments (the controls), with identical electrodes, received no current. After 12 days, each ligament was tested biomechanically with use of a hydraulic materials testing machine. Group 1 (8.6 +/- 5.9 microA) showed statistically significant improvements in maximum rupture force, energy absorbed, stiffness, and laxity. The groups that had received lower levels of current did not show significant improvements. In this study, stimulation of 1-20 microA was the most effective level of direct current for the enhancement of early healing of the medial collateral ligament.

Animals↗
PubMed1998

[Anatomic characteristics pf the elbow joint of the cheetah (Acinonyx jubatus)].

Anatomical structures of elbow joints of six cheetahs were examined by dissection, corrosion casts and radiography. As a result, it was observed that the distal end of humerus is divided into the trochlea humeri for articulation with the ulna and the capitulum humeri for articulation with the radius. As the trochlea humeri is posed oblique and looks like a disc-shaped cone sector, flexion. Flexion of elbow joint is always combined with adduction of the distal parts of the limb, and, respectively, extension with abduction. The cylindrical but also in sagittal direction convex capitulum humeri enables the head of the radius all movements on a spheric sector. Furthermore, advantageous preconditions for rotation in the proximal radioulnar joint are the mighty medical coronoid process, the displacement of the radial tuberosity to the caudal surface of the radius and the insertion of the biceps brachii muscle exclusively on this elevation of the radius. Limiting factors are the insertions of collateral ligaments at the antebrachial skeleton. The lateral collateral ligament inserts only on the radius, the medial collateral ligament mainly on the ulna. The radial anular ligament directly connects the two coronoid processes of the ulna and moreover is intracapsular. The joint capsule is common for both the cubital and the proximal radioulnar joint and five pouches could be described. These were between the lateral epicondyle of humerus and the olecranon, underneath the tendon of origin of the extensor carpi ulnaris muscle, cranially in the bend of the elbow joint, between the head of the radius and the tendon of origin of supinator muscle and the lateral part of radial anular ligament, just as between the medial epicondyle of humerus and the tendons of origin of flexor muscles of the forearm.

Acinonyx↗
PubMed1999

Early expression of marker genes in the rabbit medial collateral and anterior cruciate ligaments: the use of different viral vectors and the effects of injury.

Gene therapy is a technique that may offer advantages over current methods of cytokine delivery to ligaments. To determine if implanted genes could be expressed in normal and injured knee ligaments, the medial collateral ligament and anterior cruciate ligament were studied in 18 rabbits. A retroviral ex vivo technique using allograft medial collateral ligament and anterior cruciate ligament fibroblasts and an adenoviral in vivo technique were compared as methods for delivering the LacZ marker gene to knee ligaments. Bilateral knee surgeries were performed, and the rabbits were equally divided into three groups. Group 1 received the retrovirus and the medial collateral ligament was ruptured, Group 2 received the adenovirus and the medial collateral ligament was ruptured, and Group 3 received the adenovirus and the medial collateral ligament was not injured. The anterior cruciate ligament was not injured in any group. The medial collateral and anterior cruciate ligaments of the right knees received 10(6) allografted, transduced ligament fibroblasts or 10(9) adenovirus particles, whereas the ligaments of the left knee received a similar volume of saline solution only. Equal numbers of rabbits were killed at 10 days, 3 weeks, and 6 weeks following the procedure. Ligament samples were stained with X-gal to detect the expression of the LacZ gene product, beta-galactosidase. LacZ gene expression was evident in ruptured and uninjured medial collateral ligaments as well as in the anterior cruciate ligament. The expression lasted between 10 days and 3 weeks in the medial collateral and anterior cruciate ligaments with use of the retrovirus and between 3 and 6 weeks in the medial collateral ligament and at least 6 weeks in the anterior cruciate ligament with the adenovirus. The length of gene expression in the ruptured and uninjured medial collateral ligaments did not differ. These preliminary studies indicate that gene transfer to normal and injured knee ligaments is possible.

Adenoviridae↗