Inverted cyclops lesion after anterior cruciate ligament reconstruction

We report the case of an inverted cyclops lesion limiting extension of the knee joint after a four-strand hamstring anterior cruciate ligament (ACL) reconstruction. One case has been reported previously following a bone-tendon-bone reconstruction of the ACL but a similar case has not been reported.     

Delayed cyclops syndrome: symptomatic extension block four years after anterior cruciate ligament reconstruction

Loss of knee extension after reconstruction of the anterior cruciate ligament may occur due to a neoproliferative fibrous nodule located anterolateral to the tibial tunnel, termed cyclops syndrome. This nodule occurs usually within the early postoperative period and results in diminished knee extension due to impingement on the intercondylar notch. We report a case of a 24-year-old female patient with an uncommon delayed-onset loss of knee extension due to a cyclops syndrome four years after anterior cruciate ligament reconstruction.     

Misdiagnosis of an atypical cyclops lesion 4 years after single-bundle anterior cruciate ligament reconstruction

Development of a cyclops lesion is a well described complication after anterior cruciate ligament (ACL) reconstruction. It commonly results in gradual extension loss during the early postoperative course, and magnetic resonance imaging (MRI) of the soft tissue nodule attached to the ACL graft is needed. Cyclops lesions are easy to diagnose based on the symptoms and MRI findings. Previous study showed that 78.6% of cyclops lesions had extension loss within 6 weeks postoperatively, and the diagnosis of 92.8% cases of cyclops lesions was established within 6 months.This article describes a case of misdiagnosis of a cyclops lesion 4 years after ACL reconstruction as a meniscal lesion combined with a meniscal cyst. The patient was asymptomatic for 4 years and then presented with a locked left knee and pain at the inferior pole of the patella during an attempt to gently extend the knee. Magnetic resonance imaging revealed a lateral meniscal cyst. The knee locking was released suddenly 2 days preoperatively. The authors had attributed the missed diagnosis to an atypical history and symptoms and an associated meniscal cyst.The purpose of this article is to help prevent misdiagnosis of atypical cyclops lesions. Cyclops lesions should be considered in the differential diagnosis of patients who present with gradual or sudden loss of extension after ACL reconstruction, regardless of how much time has passed postoperatively.     

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.     

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.     

Different aspects of the cyclops lesion following anterior cruciate ligament reconstruction: A multifactorial etiopathogenesis

After anterior cruciate ligament (ACL) reconstruction using a patellar-tendon autograft, 65 patients underwent second-look arthroscopy in conjunction with hardware removal. In 23 patients, hypertrophic tissue was found in the anterior part of the knee. This tissue presented different aspects, from a well-synovialized nodule to a more disorganized fibrous tissue according to patients' complaints. Endoscopic resection of this offending tissue was generally sufficient to obtain a satisfactory result. In patients presenting a loss of extension, the notch frequently had to be enlarged. We have found a multifactorial pathogenesis to be likely: the nodule is a natural fibroproliferative tissue process originating either from drilling debris from the tibial tunnel or from remnants of the ACL stump and, more rarely, from broken graft fibers. Sometimes, when the graft is malpositioned, the scar tissue can result from repeated graft impingement on the notch at terminal extension. Formation of this aberrant tissue should be prevented by proper positioning of the graft, by enlargement of the narrowed notch in chronic cases, by using drills of increasing diameters to avoid production of osteocartilaginous fragments, by meticulous resection of all drilling debris and ACL remnants around the tibial tunnel, and by enlarging the notch roof if any contact with the graft is present when the knee is fully extended intraoperatively. (Arthroscopy 1998 Nov-Dec;14(8):869-76.)     

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.     

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.     

Osseous metaplasia as a cause of loss of extension after anterior cruciate ligament reconstruction

We report a case of osseous metaplasia of an autologous anterior cruciate ligament (ACL) reconstruction that was implicated in blocking extension of the knee. Nonoperative treatment was unsuccessful. Arthroscopic excision of the ACL and osseous metaplasia abolished the fixed flexion deformity. The osseous metaplasia was an additional factor in causing the block to extension along with an anteriorly placed femoral tunnel, raising the question that nonisometry of the graft may be involved in the pathogenesis of the osseous metaplasia.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 4 (April), 2001: pp 405–407     

Active knee motion after cruciate ligament rupture. Stereoradiography

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 stereophotogrammetric 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.     

Loss of knee extension after anterior cruciate ligament reconstruction: effects of knee position and graft tensioning

BACKGROUND: Loss of knee extension has been reported by many authors to be the most common complication following anterior cruciate ligament reconstruction. The objective of this in vitro study was to determine the effect, on loss of knee extension, of the knee flexion angle and the tension of the bone-patellar tendon-bone graft during graft fixation in a reconstruction of an anterior cruciate ligament. METHODS: The anterior cruciate ligament was reconstructed with use of tibial and femoral bone tunnels placed in the footprint of the native anterior cruciate ligament in ten cadavers. The graft was secured with an initial tension of either 44 N (10 lb) or 89 N (20 lb) applied with the knee at 0 degrees or 30 degrees of flexion. The knee flexion angle was measured with use of digital images following graft fixation. RESULTS: Tensioning of the graft at 30 degrees of knee flexion was associated with loss of knee extension in this cadaver model. Graft tension did not affect knee extension under the conditions tested. CONCLUSIONS: The results suggest that one of the common causes of the loss of full knee extension may be diminished if the graft is secured in full knee extension when the tibial and femoral tunnels are placed in the footprint of the native anterior cruciate ligament. More importantly, even when the femoral and tibial tunnels are placed in the femoral and tibial footprints of the native anterior cruciate ligament, fixing a graft in knee flexion can result in the loss of knee extension.     

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.

     

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.

     

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.     

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.     

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.