Active knee motion after cruciate ligament rupture

In 10 patients with an old injury of the anterior cruciate ligament, the three-dimensional movements of the knee joint were studied when the patients flexed their knees. Tibial motions were recorded using roentgen stereopho-togrammetric analysis. Internal rotation and adduction of the tibia were reduced in the injured knees when compared with the intact knees; during flexion of the knee joint, the tibial intercondylar eminence occupied a more lateral and posterior position on the injured side. Our results may indicate that the knee joint is continuously exposed to abnormal stresses when the anterior cruciate ligament is torn.     

Instability after anterior cruciate ligament rupture

Manual tests and 2 external devices were used together with roentgen stereophotogrammetry (RSA) and an active weight-bearing radiographic method to measure the sagittal laxity in 11 knees with anterior-cruciate-ligament rupture. In 5 knees no ligament surgery had been performed (unstable knees) and in 6 knees a reconstruction had been performed one year before the examination (stable knees). There were positive correlations between all methods, including the manual tests when all knees, both stable and unstable, were analyzed together. However, the mean values of the total displacement differed between the methods, especially when comparing the weight-bearing radiographs with the three other methods. Some knees with substantial displacement during passive loading did not show any displacement when weight bearing; the measurements thus depended on both the ligamentous laxity and the patient's neuromuscular control of the joint. When the stable knees were analyzed separately, higher mean values were recorded with the external devices than with RSA using 180 N load. This could be explained by an error from soft tissue deformation which added to the skeletal displacement when the external devices were used.     

Posterior cruciate ligament rupture alters in vitro knee kinematics

Isolated posterior cruciate ligament injuries usually are treated nonoperatively, although some patients remain symptomatic, and degenerative changes within the patellofemoral joint and the medial compartment of the tibiofemoral joint have been seen in followup studies. In vitro simulation of knee squatting was done to quantify the influence of the posterior cruciate ligament on tibiofemoral and patellofemoral kinematics. For five knee specimens, knee kinematics were measured before and after sectioning the posterior cruciate ligament, and compared using a Wilcoxon signed rank test. The only kinematic parameters that changed significantly after sectioning the posterior cruciate ligament were the tibial posterior translation and patellar flexion. The posterior translation of the tibia increased significantly between 25 degrees and 90 degrees flexion. The average increase in the posterior translation exceeded 10 mm at 90 degrees flexion. The patellar flexion increased significantly from 30 degrees to 90 degrees flexion. The average patellar flexion increase peaked at 4.4 degrees at 45 degrees flexion. Increased tibial translation could adversely influence joint stability. Increased patellar flexion could increase the patellofemoral joint pressure, especially at the inferior pole, leading to degenerative changes within the patellofemoral joint.     

Partial rupture of the anterior cruciate ligament of the knee

Ten patients are reported who had sustained a partial rupture of the anterior cruciate ligament in a twisting injury of the knee. Nine of the 10 patients presented with a small effusion and pseudo-locking of the knee which was thought to be due to muscular spasm to prevent further ligamentous injury. The patients were examined clinically, under anaesthesia and by arthroscopy and the signs were found to be remarkably similar to those in patients with a tear of the medial meniscus. The mechanism of injury leading to partial rupture of the anterior cruciate ligament is discussed.     

Isolated posterior cruciate ligament rupture presenting as a locked knee

Mechanical symptoms in the knee, especially locking, are most commonly associated with meniscal pathology. We present an atypical case of locking of the knee secondary to an isolated posterior cruciate ligament tear.     

Effects on proprioception by Kinesio taping of the knee after anterior cruciate ligament rupture

Introduction

The use of Kinesio tape (KT) to improve proprioception is a matter of considerable debate. In comparison, the rupture of the anterior cruciate ligament is a sufficiently well-investigated injury with a proven compromise of proprioception. The objective of the present study was to assess a supportive effect on proprioception after KT application, taking the anterior cruciate ligament (ACL) rupture as an example.

Materials and methods

Forty-eight patients who had suffered an ACL rupture, confirmed clinically and by magnetic resonance imaging, and who were treated conservatively or were awaiting surgery were included in this study. In all patients, a gait analysis was performed on the affected leg before and after KT application. In addition, the IKDC score, the Lysholm score, stability using the Rolimeter, and the angle reproduction test were determined.

Results

Thirty-nine men and nine women who had had an ACL rupture for at least 3 weeks were included in the study. Significant improvements were achieved on the affected knee joint for the gait analysis parameters touchdown and unrolling, cadence, stability and stance phase as well as an extension of the hip joint. The Lysholm score improved from 79.3 to 85.8 (p?<?0.001) and the IKDC score from 60.2 to 71.3 points (p?<?0.001). Significant improvements were achieved in the Rolimeter and angle reproduction test.

Conclusions

The use of KT has a positive effect on proprioception in patients with an anterior cruciate ligament rupture. Therefore, the application may improve gait pattern as well as the subjective function of the affected knee joint.

     

Three-dimensional knee joint movements during a step-up: Evaluation after anterior cruciate ligament rupture

The three-dimensional motions of the knee were analysed during closed kinetic chain knee extension in 13 patients with unilateral chronic injury of the anterior cruciate ligament. The patients ascended a platform, and serial stereophotogrammetric roentgenograms were exposed from about 100° of flexion to full extension. From a position of about 100° of knee flexion and 20° of internal rotation, the tibia rotated externally during the extension. Almost no tibial adduction or abduction was observed. The tibial intercondylar eminence translated laterally, distally, and anteriorly relative to the femur. In knees with absence of the anterior cruciate ligament, the intercondylar eminence had a more posterior position compared with the contralateral normal knees. The proximal tibia was used as a fixed reference segment to evaluate the anteroposterior translations of a central point in the femoral condyles. The femoral point was more anteriorly displaced in the injured than in the contralateral knees. This difference might reflect increased activity of the hamstrings in the injured knees, because it was most pronounced at 80° of flexion and decreased with increasing extension. In the sagittal plane, the mean helical axis was positioned close to the femoral insertion of the ligament at 80° of flexion and was displaced distally and anteriorly during extension. In the frontal plane, the axis had a transverse direction at 80° of flexion. At close to full extension, the axis was positioned distally in the lateral condyle and proximally in the medial condyle. In the horizontal plane, the helical axes ran slightly more anteriorly in the medial than in the lateral femoral condyle but changed inclination at close to full extension and became almost parallel to the transverse axis.     

Proprioception and performance after anterior cruciate ligament rupture

The aim of this study was to investigate the characteristics of proprioception in patients with an anaterior-cruciate-ligament (ACL)-injured knee and to determine whether there is a correlation between proprioception and performance. We studied 32 patients with unilateral isolated ACL ruptures. Proprioception of the knee was evaluated by examining the joint position sense. Functional performance was evaluated with the one-leg hop (OLH) and one-leg vertical jump (OLV) tests. The mean error angle of the joint position sense was 3.6±1.5° on the intact side and 5.2±1.9° on the injured side. The joint position sense was thus clearly reduced on the injured side (p<0.05). The distance of jumping in the OLH test and the height of jumping in the OLV test was also clearly reduced on the injured side compared with that on the intact side (p<0.01) both with and without visual control. Moreover, we found a significant correlation between proprioception and performance in the ACL-injured knees, and this correlation was more distinct with visual deprivation. In conclusion, decreased proprioception in patients with ACL deficiency reduced their functional ability.

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Résumé Le but de cette étude était détudier les caractéristiques de proprioception chez les malades avec une lésion du LCA, et déterminer sil y avait une corrélation entre proprioception et performance. Nous avons étudié 32 malades avec une rupture isolée unilatérale du LCA. La proprioception du genou a été évalué en examinant le sens des positions de larticulation. La fonction a été évaluée avec le saut à cloche-pied (OLH) et saut vertical unipodal (OLV). Langle moyen derreur de position était 3,6±1,5° sur le côté intact et 5,2±1,9° sur le côté blessé. Le sens de position était donc notablement réduit du côté blessé (p<0.05). La distance de saut dans lépreuve OLH et la hauteur du saut dans lépreuve OLV ont aussi été réduite du côté blessé comparé avec le côté intact (p<0.01) les deux avec et sans contrôle visuel. De plus, nous avons trouvé une corrélation certaine entre proprioception et performance dans les genoux avec lésion du LCA, et cette corrélation était encore plus nette avec privation visuelle. En conclusion, la diminution de la proprioception chez les malades avec une insuffisance du LCA à réduit leur capacité fonctionnelle.

     

Total knee arthroplasty after anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) injuries are common, and many of these patients go on to ACL reconstruction. At a later date, some may develop symptomatic osteoarthritis and require total knee arthroplasty (TKA). This raises the question: Does prior ACL reconstruction have a deleterious impact on the outcome of knee arthroplasty? Thirty-six cases of patients who underwent ACL reconstruction and then TKA at a later date were retrospectively reviewed. A cohort of patients without ACL injuries who underwent TKA for the diagnosis of primary osteoarthritis were selected to serve as controls. The results of this study demonstrate that previous ACL reconstruction does not have a negative impact on the outcome of future TKA with respect to range of motion, outcome scores, infection, or patella baja.     

The cyclops lesion: a cause of diminished knee extension after rupture of the anterior cruciate ligament.

Four patients presented with persistent diminution of knee motion after rupture of the anterior cruciate ligament with a novel lesion as the cause. Each had participated in an aggressive rehabilitation program for a minimum of 2 months with emphasis on regaining full range of knee motion. Because chronic impairment of knee extension can be disabling, in those who did not regain full range of motion, arthroscopy of the knee ensued. All had a lesion in the intercondylar notch near the tibial insertion of the anterior cruciate ligament that acted as a mechanical obstruction to full knee extension. Grossly and histologically, these were similar to the cyclops lesion that also has been shown to cause loss of knee extension after anterior cruciate ligament reconstruction. Arthroscopic debridement of the cyclops lesion and manual manipulation of the knee under anesthesia lead to restoration of full knee extension in all knees. In 1 other knee with chronic instability after anterior cruciate ligament rupture, the cyclops lesion was present but was very small and was not associated with diminished knee extension. When loss of full extension persists for 2 months after anterior cruciate ligament disruption despite aggressive rehabilitation, the presence of a cyclops lesion should be considered.     

Anterior and posterior cruciate ligament rupture after thermal treatment

Summary: This article reports the first published case of spontaneous, simultaneous rupture of both the anterior and posterior cruciate ligaments 3 months after radiofrequency thermal probe treatment. The patient had no previous traumatic injury to the knee. Simultaneous rupture occurred under minimal physiologic load. Clinical, radiologic, and surgical findings are presented.Arthroscopy: The Journal of Arthroscopic and Related surgery, Vol 16, No 7 (October), 2000: pp 732–736     

Graft tension and knee stability after anterior cruciate ligament reconstruction.

This study examined the effect of the initial graft tension on the clinical outcome of anterior cruciate ligament reconstruction in a prospective randomized design. Fifty patients were enrolled in the study. In the reconstructive procedure, a bone-patellar tendon-bone graft was used. A set force of 25 N (5.6 lb) was applied in 25 patients and 50 N (11.2 lb) tension was maintained during fixation for the remaining 25 patients with the knee in full extension. In the immediate postoperative period, the anterior cruciate ligament reconstructed knee was similarly overconstrained in both groups. At 3 months, laxity of the surgically treated knee in both groups had increased significantly and become close to that of the contralateral knee. Measured laxity value showed a slight increase between 3 and 6 months, and remained similar thereafter. No significant difference in the clinical outcome was observed between the groups throughout the followup.     

Rehabilitation of the knee after anterior cruciate ligament reconstruction

From the Kerlan-Jobe Orthopaedic Clinic, 501 E. Hardy Street, Suite 200, Inglewood, CA 90301. New information regarding the isometric placement of the anterior cruciate ligament (ACL) substitute, revascularization process, and biomechanical stresses have all contributed to and been incorporated in the rehabilitation program after ACL reconstruction. Treatment protocols specifically designed for the patient following ACL reconstruction are imperative to return the individual to his or her preinjury status. Care is taken to limit the amount of stress placed on the ligament substitute especially at end of range extension. A program incorporating techniques for developing range of motion and strength while still preserving stability at the knee joint is still of the utmost importance. This program is a revision of a previously reported regimen from this facility (Brewster, Moynes, Jobe, J Orthop Sports Phys Ther 5:121-126, 1983) and is based upon clinical experience and research information. J Orthop Sports Phys Ther 1989;11(1):8-18.     

Histological changes in the human anterior cruciate ligament after rupture

BACKGROUND: Four phases in the response to injury of the ruptured human anterior cruciate ligament are observed histologically; these include an inflammatory phase, an epiligamentous repair phase, a proliferative phase, and a remodeling phase. One objective of this study was to describe the histological changes that occur in the ruptured human anterior cruciate ligament during these phases. Myofibroblast-like cells that contain alpha-smooth muscle actin are present in the midsubstance of the intact human anterior cruciate ligament. A second objective of this study was to determine whether an increased number of myofibroblast-like cells is found in the midsubstance of the ruptured human anterior cruciate ligament because it was thought that those cells might be responsible in part for the retraction of the ruptured anterior cruciate ligament. In the early phase of this study, it was found that the number of myofibroblast-like cells in the midsubstance of the ruptured anterior cruciate ligament was actually decreased, and this hypothesis was abandoned. During the epiligamentous repair phase, synovial tissue was formed that covered the ends of the ruptured anterior cruciate ligament. Most of the synovial lining cells were myofibroblast-like cells that contained alpha-smooth muscle actin. The primary objective of this study was to determine the location and the characteristics of the alpha-smooth muscle actin-containing myofibroblast-like cells that appear in the human anterior cruciate ligament following rupture. METHODS: Twenty-three ruptured and ten intact human anterior cruciate ligaments were evaluated for cellularity, nuclear morphology, blood vessel density, and percentage of cells containing a contractile actin isoform, alpha-smooth muscle actin. The histological features of the synovial and epiligamentous tissues were also described. RESULTS: At no time after rupture was there evidence of tissue-bridging between the femoral and tibial remnants of the anterior cruciate ligament. The ruptured ligaments demonstrated a time-dependent histological response, which consisted of inflammatory cell infiltration up to three weeks, gradual epiligamentous repair and resynovialization between three and eight weeks, and neovascularization and an increase in cell number density between eight and twenty weeks. Compared with the intact ligaments, there was a decrease in the percentage of myofibroblast-like cells containing alpha-smooth muscle actin within the remnant of the ligament. However, many of the epiligamentous and synovial cells encapsulating the remnants contained alpha-smooth muscle actin. CONCLUSIONS: After rupture, the human anterior cruciate ligament undergoes four histological phases, consisting of inflammation, epiligamentous regeneration, proliferation, and remodeling. The response to injury is similar to that reported in other dense connective tissues, with three exceptions: formation of an alpha-smooth muscle actin-expressing synovial cell layer on the surface of the ruptured ends, the lack of any tissue bridging the rupture site, and the presence of an epiligamentous reparative phase that lasts eight to twelve weeks. Other characteristics reported in healing dense connective tissue, such as fibroblast proliferation, expression of alpha-smooth muscle actin, and revascularization, also occur in the ruptured human anterior cruciate ligament. CLINICAL RELEVANCE: Unlike extra-articular ligaments that heal after injury, the human intra-articular anterior cruciate ligament forms a layer of synovial tissue over the ruptured surface, which may impede repair of the ligament. Moreover, a large number of cells in this synovial layer and in the epiligamentous tissue express the gene for a contractile actin isoform, alpha-smooth muscle actin, thus differentiating into myofibroblasts. These events may play a role in the retraction and lack of healing of the ruptured anterior cruciate ligament.     

Posterior cruciate ligament removal contributes to abnormal knee motion during posterior stabilized total knee arthroplasty

Abnormal anterior translation of the femur on the tibia has been observed in mid flexion (20–60°) following posterior stabilized total knee arthroplasty. The underlying biomechanical causes of this abnormal motion remain unknown. The purpose of this study was to isolate the effects of posterior cruciate ligament removal on knee motion after total knee arthroplasty. We posed two questions: Does removing the posterior cruciate ligament introduce abnormal anterior femoral translation? Does implanting a posterior stabilized prosthesis change the kinematics from the cruciate deficient case? Using a navigation system, we measured passive knee kinematics of ten male osteoarthritic patients during surgery after initial exposure, after removing the anterior cruciate ligament, after removing the posterior cruciate ligament, and after implanting the prosthesis. Passively flexing and extending the knee, we calculated anterior femoral translation and the flexion angle at which femoral rollback began. Removing the posterior cruciate ligament doubled anterior translation (from 5.1 ± 4.3 mm to 10.4 ± 5.1 mm) and increased the flexion angle at which femoral rollback began (from 31.2 ± 9.6° to 49.3 ± 7.3°). Implanting the prosthesis increased the amount of anterior translation (to 16.1 ± 4.4 mm), and did not change the flexion angle at which femoral rollback began. Abnormal anterior translation was observed in low and mid flexion (0–60°) after removing the posterior cruciate ligament, and normal motion was not restored by the posterior stabilized prosthesis. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1494–1499, 2008