Isolated sectioning of the medial and posteromedial capsular ligaments in the posterior cruciate ligament-deficient knee. Influence on posterior tibial translation

OBJECTIVES: This study examined whether heightened cardiovascular reactivity and low socioeconomic status had synergistic effects on the progression of carotid atherosclerosis in a population of eastern Finnish men. METHODS: Data from the Kuopio Ischemic Heart Disease Risk Factor Study were used to measure 4-year progression of intima-media thickness in 882 men according to cardiovascular reactivity and socioeconomic status. Associations were examined in relation to risk factors and were stratified by baseline levels of atherosclerosis and prevalent ischemic heart disease. RESULTS: The effect of reactivity on atherosclerotic progression depended on socioeconomic status. Men who had heightened cardiovascular responsiveness to stress and were born into poor families, received little education, or had low incomes had the greatest atherosclerotic progression. CONCLUSIONS: An understanding of associations between individual risk factors and disease should be based on etiologic hypotheses that are conceived at the population level and involve fundamental social and economic causes of disease. This study demonstrates how examining the interaction of an individual biological predisposition will low socioeconomic status over the life course is etiologically informative for understanding the progression of atherosclerotic vascular disease.     

Symptomatic intraarticular ganglia of the cruciate ligaments of the knee

This case report draws attention to the clinical presentation, differential diagnosis, and recommended diagnostic modality and treatment of symptomatic ganglia of the anterior and posterior cruciate ligaments. One patient presented with a recurrent inability to fully extend the left knee. Another patient presented with pain and soreness over the lateral aspect of the knee, including the lateral joint line. The diagnosis of ganglia of the cruciate ligaments was made after clinical, radiographic, and magnetic resonance examination. Both patients were treated successfully with resection of their ganglia using arthroscopic techniques.     

Functional testing in the anterior cruciate ligament-deficient knee

Functional testing of patients with anterior cruciate ligament (ACL) deficient knees and normal subjects during stressful activities such as running to a cut and running to a stop and during activities common to daily life, such as walking, stair climbing, and jogging, is presented. Analysis focused on the application of these tests to treatment planning and clinical evaluation. Functional testing during stressful activities indicates that some patients with ACL-deficient knees have higher than normal net hamstring moments during the early phase of these activities. These results suggest dynamic muscular substitution using the hamstrings in patients with chronic ACL-deficient knees. Patients tested during less stressful activities, such as walking and stair climbing, also demonstrated substantial differences from ACL-intact subjects. The majority of patients tended to reduce the net quadriceps moment when the knee was near full extension. Approximately 75% of the patients who were ACL-deficient developed this type of adaptation, which appears to be a subconscious method of avoiding the net anterior pull of the quadriceps mechanism when the knee is near full extension. Functional testing of the ACL-deficient knee provides meaningful information that cannot be obtained by simpler clinical tests. This information can be extremely useful in the selection and evaluation of patients with certain treatment modalities, since it seems to be directly related to some patients' ability to functionally adapt to the loss of the ACL.     

Analysis of proprioception in the posterior cruciate ligament-deficient knee

Preseptal cellulitis has a typically benign course when treated with antibiotics, the clinical course depending on age of the patient, aetiology and the causative organism. In this study, 14 cases of preseptal cellulitis are documented with the age ranging from 2 to 55 years. The organisms isolated were Staphylococcus aureus (7 cases), Streptococcus pyogenes (2 cases) and Pseudomonas aeruginosa (1 case). In the remaining four patients no organism could be identified. All except four patients were cured within 6 weeks. Complications seen included lagophthalmos, lid abscess, cicatricial ectropion and lid necrosis in one patient each. The prognosis for preseptal cellulitis is good with appropriate antibiotics and surgical therapy.     

Lateral-compartment bone contusions in adolescents with intact anterior cruciate ligaments

PURPOSE: To determine how often lateral-compartment bone contusions are seen on magnetic resonance (MR) images of knees in adolescents with intact anterior cruciate ligaments (ACLs). MATERIALS AND METHODS: MR images obtained in 53 adolescent patients (30 male, 23 female; aged 10-20 years) were reviewed to detect bone contusions in the posterolateral tibial plateau or the lateral femoral condyle. ACLs were also evaluated with accepted criteria for the diagnosis of ligamental disruption. Only patients referred for evaluation of a knee injury or mechanical symptoms were included. RESULTS: Five patients with bone contusions had an intact ACL at MR imaging. One of the five had arthroscopic confirmation. Fifteen other patients had complete ACL disruptions: 13 of these patients had typical bone contusions; the other two had no bone abnormalities but had chronic ACL tears. Thus, 28% of the 18 patients with typical bone contusions had intact ACLs. CONCLUSION: Adolescents may have the same pattern of contusions as adults but may maintain an intact ACL owing to increased ligamentous laxity.     

Gait characteristics of the anterior cruciate ligament-deficient varus knee

Of the two visual systems in vertebrates, the tectofugal pathway has often been attributed to stimulus localization, while the thalamofugal pathway was thought to be involved in stimulus identification. This review provides evidence that the tectofugal pathway serves both functions. It is speculated that the initial task of the tectum is to localize an object and to guide the fixation movement. The object in focus is then analysed by the higher stations of the tectofugal system. The result of the analysis is fed into the optic tectum and is used for decision about the treatment of the object.     

Injuries of the medial collateral ligament and anterior cruciate ligament of the knee joint and Lemaire surgical functional treatment. Long-term outcome

The present paper reports the results of 112 extraarticular ligamento-plasties performed on the knee with the procedure proposed by Lemaire. The series includes isolated tears of the anterior cruciate and medical collateral ligament as well as combined tears of both ligaments. The clinical and radiological results with a mean follow-up time of 11.5 years are compared with the results obtained in a first assessment 8 years ago. Good clinical results are in contrast with increasing osteoarthrosis in 1/3 of the knees radiologically assessed. The operation for a torn anterior cruciate ligament should be performed as soon as possible to avoid secondary meniscal lesions with subsequent severe osteoarthrosis. Presence or absence of arthrotic signs in the X-rays mainly determine the long-term result after ligamento-plasties of the knee. The Lemaire plasties are well tolerated even by elderly still active people and need little postoperative care.     

Role of the posterior cruciate ligament in total knee arthroplasty

Accumulating evidence indicates that protein kinase C (PKC)-dependent, Ca2+-independent smooth muscle contraction plays the central role in the occurrence of chronic vasospasm following aneurysmal subarachnoid hemorrhage. As far as we know, the nitric oxide/ cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) system comprises the most efficacious inhibitory mechanism against the PKC-dependent contractile mechanism, and the myogenic tonus of normal cerebral arteries is thought to be maintained on the balance between these systems. Recent studies indicate that in spastic cerebral arteries, the rise in the intracellular diacylglycerol level causes PKC activation presumably owing to the overexpression of endothelin (ET)-1 as well as the generation of free radicals, whereas the cGMP level is inversely reduced owing to the inactivation of soluble guanylate cyclase through some as yet unknown mechanism. The resultant loss of balance between the two systems is considered to culminate in the occurrence of chronic vasospasm lasting for nearly 2 weeks. Based on the above concept, recent papers concerning the effects of reactive oxygen species on the arterial smooth muscle, alterations of various membrane ion channels, particularly of adenosine triphospate (ATP)-activated potassium channels in spastic arteries, the preventive effects of ET antagonists on vasospasm, and the causative role of ET-1 were reviewed in the present article. The roles of the above spasmogenic factors or mechanisms may be more clearly understood on the basis of the antagonistic interrelation between the PKC and the PKG systems, which exert diverse influences on the force-generating system as well as on its multifarious regulatory mechanisms in smooth muscle cells.     

Value of posterior cruciate ligament index in the diagnosis of anterior cruciate ligament injuries

Several EF-hand recoverin mutants were obtained and their abilities to bind to photoreceptor membranes and to inhibit rhodopsin kinase were determined. The mutants with the 'spoiled' 2nd, 3rd or (2nd+3rd) EF-hand structures did not act upon the kinase activity in the microM range of Ca2+ concentrations. Mutations of the 4th EF hand, which 'repaired' its Ca2+-binding activity, resulted in recoverin with three 'working' Ca2+-binding sites. The latter mutant inhibited rhodopsin kinase even more effectively than the wild-type recoverin, containing two working Ca2+-binding structures.     

The relationship between anterior cruciate ligament reconstruction tibial tunnel location and the anterior aspect of the posterior cruciate ligament insertion

OBJECTIVE: To assess the outcome of 31 patients treated in a day and semi-residential psychotherapy setting. METHOD: Patients had moderate to severe personality difficulties and were referred when current therapy was insufficient or because of the severity of their problems. Eighty-one percent had a Cluster C and 19% a Cluster B (Borderline) Personality Disorder diagnosis (DSM-III-R). Therapy was psychodynamically and feministin-formed and included a sociopolitical dimension. Rating scales used were the Symptom Checklist 90, Goal Attainment Scale, Global Assessment Scale and measures of health resource usage, which were completed pre-treatment, post-treatment and at 4-, 12- and 24-month follow-up. RESULTS: Mean duration of therapy was 4 months (68 therapy days). All clinical rating scales demonstrated marked improvements following treatment (p < 0.0001) which were sustained at 2-year follow-up. There were also improvements of health resource usage. CONCLUSIONS: The results document the clinical efficacy of psychotherapy in this setting, provide support for the philosophy of practice, and suggest that psychotherapy outcome can be evaluated at reasonable financial cost in many settings.     

Radionuclide imaging of the knee with chronic anterior cruciate ligament tear

We studied the results of bone scans in 50 consecutive patients with symptomatic, unilateral, chronic anterior cruciate ligament (ACL) tears. All patients had failed conservative therapy and underwent radionuclide imaging of the knee prior to arthroscopic ACL reconstruction. The scintigraphic activity in each of the three knee compartments was quantitatively scaled from 1 (normal scintigraphic activity) to 4 (marked activity). Quantitative activity in each of the three compartments was correlated with plain radiographic, arthroscopic, and clinical findings. All but four of the scans (92%) showed abnormal scintigraphic activity. The quantitative activity was highest overall in the medial compartment (2.9), followed by the lateral (2.4) and patellofemoral compartments (1.9). In the subgroup of patients with normal menisci (10 patients), most of the abnormal activity was in the lateral compartment (2.9), implying that when the medial meniscus remains competent in the presence of a torn ACL, there is increased stress on the lateral compartment. There was little correlation with scintigraphy and roentgenographic changes, except in the presence of moderate or severe radiographic degenerative arthritis. Similarly, there was little correlation between increased scintigraphic activity and chondromalacia. These results provide a baseline for future studies that use scintigraphic imaging in monitoring restoration of bone homeostasis following ACL reconstruction.     

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

The role of the posterolateral and cruciate ligaments in restraining knee motion was studied in 11 human cadaveric knees. The posterolateral ligaments sectioned included the lateral collateral and arcuate ligaments, the popliteofibular ligament, and the popliteal tendon attachment to the tibia. Combined sectioning of the anterior cruciate and posterolateral ligaments resulted in maximal increases in primary anterior and posterior translations at 30 degrees of knee flexion. Primary varus, primary internal, and coupled external rotation also increased and were maximal at 30 degrees of knee flexion. Combined sectioning of the posterior cruciate and posterolateral ligaments resulted in increased primary posterior translation, primary varus and external rotation, and coupled external rotation at all angles of knee flexion. Examination of the knee at 30 degrees and 90 degrees of knee flexion can discriminate between combined posterior cruciate ligament and posterolateral injury and isolated posterolateral injury. The standard external rotation test performed at 30 degrees of knee flexion may not be routinely reliable for detecting combined anterior cruciate and posterolateral ligament injury. However, measurements of primary anterior-posterior translation, primary varus rotation, and coupled external rotation may be used to detect combined anterior cruciate and posterolateral ligament injury.     

Eccentric knee flexor torque following anterior cruciate ligament surgery

The purposes of this study were to compare eccentric knee flexor torque and muscle activation in the limbs of normal (NOR) subjects and in subjects who had undergone unilateral ACI, autograft surgical reconstruction (INJ) and to assess the effect of movement speed on EMG/ torque ratios and eccentric-concentric actions. Fourteen subjects (7 NOR and 7 INJ) were tested for knee eccentric flexor torque and EMG activity at four isokinetic speeds (15 degrees, 30 degrees, 45 degrees and 60 degrees.s-1). Results revealed that post-surgical limbs (ACL) produced significantly less (P < 0.05) eccentric torque and flexor EMG activity at 60 degrees.s-1 than uninjured (UNI) contralateral limbs. Eccentric torque rose significantly as speed increased from 45 degrees to 60 degrees.s-1 for surgical group uninjured limbs and NOR group left and right limbs. Eccentric flexor torque increased with speed for both groups and approximated equality with concentric extensor torque at 60 degrees.s-1 for INJ group ACL and UNI limbs. Concentric flexor muscle EMG/torque ratios were 30-191% greater than eccentric muscle actions across groups and speeds. The results suggest that ACL dysfunction may result in reduced eccentric flexor torque at rapid movement speeds, that eccentric flexor torque increases with movement speed and may have the capacity to counter forceful extensor concentric torque, and that eccentric muscle actions produce less muscle activation per unit force than concentric actions which may reflect reduced energy cost.     

Sagittal plane translations of the knee in anterior cruciate deficient subjects and controls

Static anterior-posterior (AP) laxity is one of the commonly used criteria in selecting patients for cruciate ligament reconstructions, but in reality dynamic AP laxity plays a more important role. The aim of this in vivo study was to compare the sagittal translation of the knee during active and passive motion, signifying dynamic AP laxity, with static AP laxity in healthy subjects (controls) and patients with anterior cruciate ligament deficiency. The sagittal plane knee translations were recorded and compared in both knees of nine healthy subjects (Controls) and seven patients with confirmed unilateral ACL deficiency during dynamic and static situations with an electrogoniometer system. In all groups during the ascents the tibia moved anteriorly in relation to the femur, whereas during the descents it moved posteriorly. The static anterior-posterior translation was significantly smaller in the control knee than in both healthy and injured knees of the ACL deficient group (P < 0.05). The injured knee showed the same laxity (92%) as the uninjured knee during dynamic activities, but it was 46% of static laxity. Also in the injured knees, the dynamic active laxity was larger during descents than ascents (P < 0.05). The results indicate that there is also a change in mechanics of the noninjured knee following injury to the contralateral knee and that this population of patients with ACL deficiency had good control over their abnormal anterior-posterior laxity.     

Flexion instability after primary posterior cruciate retaining total knee arthroplasty

Between 1990 and 1995, 25 painful primary posterior cruciate ligament retaining total knee arthroplasties were revised for flexion instability. These patients shared typical clinical presentations that included a sense of instability without frank giving way, recurrent knee joint effusion, soft tissue tenderness involving the pes anserine tendons and the retinacular tissue, posterior instability of 2+ or 3+ with a posterior drawer or a posterior sag sign at 90 degrees flexion, and above average motion of their total knee arthroplasty. The primary total knee arthroplasty was performed for osteoarthritis in 23 patients and rheumatoid arthritis in two patients. There were 13 male and 12 female patients and their mean age was 65 years (range, 35-77 years). Before the revision operation, Knee Society knee scores averaged 45 points (range, 17-68 points) and function scores averaged 42 points (range, 0-60 points). Twenty-two of the knee replacements were revised to posterior stabilized implants and three underwent tibial polyethylene liner exchange only. Nineteen of the 22 knee replacements revised to a posterior stabilized implant were improved markedly after the revision surgery. Only one of three knee replacements that underwent tibial polyethylene exchange was improved. After the revision for flexion instability, Knee Society knee scores averaged 90 points (range, 82-99 points) and function scores averaged 75 points (range, 45-100 points) for the 20 knees with a successful outcome. This study suggests that flexion instability can be a cause of persistent pain and functional impairment after posterior cruciate ligament retaining total knee arthroplasty. A revision operation that focuses on balancing the flexion and extension spaces, in conjunction with a posterior stabilized knee implant, seems to be a reliable treatment for symptomatic flexion instability after posterior cruciate retaining total knee arthroplasty.     

MR imaging of the knee ligaments and the postoperative knee

MR imaging is an accurate, noninvasive, and cost-effective method for the evaluation of acute knee ligament injuries and in the examination of the postoperative knee. Understanding the normal anatomy and the pertinent clinical aspects of knee injuries is a prerequisite for accurate interpretation of MR imaging studies. The increasing popularity of ACL reconstruction following disruption of this ligament requires knowledge of the various surgical techniques and their MR imaging appearance as well as the appearance of possible complications.     

Early, incapacitating instability of posterior cruciate ligament-retaining total knee arthroplasty

Numerous studies indicate that total knee arthroplasty (TKA) achieves excellent long-term success whether the posterior cruciate ligament (PCL) is saved or excised. In 13 patients, 16 PCL-retaining TKAs were identified with incapacitating instability secondary to early PCL deficiency. Patients with clinical PCL insufficiency present with a triad of subjective complaints: persistent swelling/effusions, anterior knee pain, and giving-way or instability episodes with activities of daily living. Of 13 patients, 12 had at least three postoperative visits with identical subjective complaints before PCL deficiency was diagnosed. On examination all patients exhibited effusion, posterior sag, positive quadriceps active test, and a visible anterior translation of the tibia on the femur while extending the leg from a seated, 90 degree flexed position. This sign has not been previously described to our knowledge but was present in all of our study patients. No patients had radiographic evidence of loosening or osteolysis. Joint aspiration was negative for infection in all patients. No patient had lateral patellofemoral maltracking. By radiographic measurement, the PCL-deficient knees had an average joint line elevation of 10.3 mm, compared with well-functioning TKAs which had an average joint line elevation of 5.0 mm. There was no correlation of PCL deficiency with excessive proximal tibial resection. Nonsurgical intervention provided no improvement in pain or instability. Six patients had improvement of pain, effusion, and stability after revision to a cruciate-substituting implant. We believe that this complication occurs more frequently than is currently being identified and should be considered in problem TKAs with normal radiographs.     

Effect of partial release of the posterior cruciate ligament in total knee arthroplasty

Appropriate tension of the posterior cruciate ligament, which often is tight in deep flexion, is difficult to achieve after posterior cruciate ligament retaining total knee arthroplasty. Kinematics and maximum flexion after partial release of the posterior cruciate ligament were evaluated in this study. A partial release improved the maximum flexion angle and maintained anteroposterior stability without causing undesirable changes in kinematics, whereas full resection of the posterior cruciate ligament caused unfavorable anteroposterior instability. Partial posterior cruciate ligament release eliminated excessive rollback movement caused by a tight posterior cruciate ligament and also shifted the point of articular surface contact anteriorly. These results indicate that partial release of the posterior cruciate ligament may improve knee function in patients with a tight posterior cruciate ligament after total knee arthroplasty.     

Anterior knee laxity and loss of extension after anterior cruciate ligament injury

This study was performed to examine the relationship between knee extension loss and the length of time after injury. We also wanted to compare anterior laxity in anterior cruciate ligament-injured knees in the early and late stages of injury. Loss of knee extension was measured in 81 patients with anterior cruciate ligament injury using lateral radiography with the injured leg relaxed and elevated. Extension loss was defined as the difference in maximal extension angle between the injured and uninjured knees. Average loss of extension was 3.6 degrees in the 17 knees in which the anterior cruciate ligament had been torn 3 weeks or less before examination (the acute injury group) and 0.6 degree in the 64 knees in which the anterior cruciate ligament had been torn more than 3 weeks before examination (the chronic injury group). The extension loss in the acutely injured knees was significantly greater compared with that in the uninjured knees and in the chronically injured knees. Arthrometric measurements using the KT-1000 arthrometer were reliable to diagnose an acute tear. There was no correlation between the degree of extension loss and arthrometric anterior knee laxity measurements. In 12 patients, the initial extension deficit in the early stage of injury significantly resolved with time, and manual maximum arthrometric measurements of anterior knee laxity improved spontaneously with time.     

The effect of femoral tunnel position and graft tensioning technique on posterior laxity of the posterior cruciate ligament-reconstructed knee

We report the effects of femoral tunnel position and graft tensioning technique on posterior laxity of the posterior cruciate ligament-reconstructed knee. An isometric femoral tunnel site was located using a specially designed alignment jig. Additional femoral tunnel positions were located 5 mm proximal and distal to the isometric femoral tunnel. With the graft in the proximal femoral tunnel, graft tension decreased as the knee flexed; with the graft in the distal femoral tunnel, graft tension increased as the knee flexed. When the graft was placed in the isometric femoral tunnel, a nearly isometric graft tension was maintained between 0 degrees and 90 degrees of knee flexion. One technique tested was tensioning the graft at 90 degrees of knee flexion while applying an anterior drawer force of 156 N to the tibia. This technique restored statistically normal posterior stability to the posterior cruciate ligament-deficient knee between 0 degrees and 90 degrees for the distal femoral tunnel position, between 0 degrees and 75 degrees for the isometric tunnel position, and between 0 degrees and 45 degrees for the proximal tunnel position. When the graft was tensioned with the knee in full extension and without the application of an anterior drawer force, posterior translation of the reconstructed knee was significantly different from that of the intact knee between 15 degrees and 90 degrees for all femoral tunnel positions.