The contribution of each anterior cruciate ligament bundle to the Lachman test: a cadaver investigation

The clinical diagnosis of a partial tear of the anterior cruciate ligament (ACL) is still subject to debate. Little is known about the contribution of each ACL bundle during the Lachman test. We investigated this using six fresh-frozen cadaveric lower limbs. Screws were placed in the femora and tibiae as fixed landmarks for digitisation of the bone positions. The femur was secured horizontally in a clamp. A metal hook was screwed to the tibial tubercle and used to apply a load of 150?N directed anteroposteriorly to the tibia to simulate the Lachman test. The knees then received constant axial compression and 3D knee kinematic data were collected by digitising the screw head positions in 30° flexion under each test condition. Measurements of tibial translation and rotation were made, first with the ACL intact, then after sequential cutting of the ACL bundles, and finally after complete division of the ACL. Two-way analysis of variance analysis was performed. During the Lachman test, in all knees and in all test conditions, lateral tibial translation exceeded that on the medial side. With an intact ACL, both anterior and lateral tibial landmarks translated significantly more than those on the medial side (p < 0.001). With sequential division of the ACL bundles, selective cutting of the posterolateral bundle (PLB) did not increase translation of any landmark compared with when the ACL remained intact. Cutting the anteromedial bundle (AMB) resulted in an increased anterior translation of all landmarks. Compared to the intact ACL, when the ACL was fully transected a significant increase in anterior translation of all landmarks occurred (p < 0.001). However, anterior tibial translation was almost identical after AMB or complete ACL division. We found that the AMB confers its most significant contribution to tibial translation during the Lachman test, whereas the PLB has a negligible effect on anterior translation. Section of the PLB had a greater effect on increasing the internal rotation of the tibia than the AMB. However, its contribution of a mean of 2.8° amplitude remains low. The clinical relevance of our investigation suggests that, based on anterior tibial translation only, one cannot distinguish between a full ACL and an isolated AMB tear. Isolated PLB tears cannot be detected solely by the Lachman test, as this bundle probably contributes more resistance to the pivot shift.     

Incomplete ruptures of the anterior cruciate ligament

In a prospective study, 41 consecutive patients with a partial tear of the anterior cruciate ligament, diagnosed by arthroscopy, were reviewed after an average of 17 months, having been in plaster for six weeks after injury. Their average age was 29 years and review included clinical examination, measurement of anterior and posterior laxity with the Stryker knee laxity tester as well as evaluation of knee function and activity level. Twenty-one patients had unstable knees at follow-up; the mean total anteroposterior laxity for these patients was 12.6 +/- 3.9 mm compared with 7.1 +/- 4.3 mm for the normal knee. Most patients had few symptoms, but there was a significant reduction in the mean level of activity in the unstable group.     

Knee instability after injury to the anterior cruciate ligament. Quantification of the Lachman test

We have measured anterior and posterior displacement in 563 normal knees and 487 knees with chronic deficiency of the anterior cruciate ligament (ACL). We performed stress radiography using a simple apparatus which maintained the knee at 20 degrees of flexion while a 9 kg load was applied. There was no significant difference in posterior translation dependent on the condition of the ACL. Measurement of anterior translation in the medial compartment proved to be more reliable than in the lateral compartment for the diagnosis of rupture of the ACL, with better specificity, sensitivity and predictive values. We have classified anterior laxity based on the differential anterior translation of the medial compartment and identified four grades in each of which we can further distinguish four subgrades for laxity of the lateral compartment. Within each of these subgroups, either internal or external rotation may dominate and sometimes there is a major translation of both compartments. Radiological evaluation of displacement of the knee in 20 degrees of flexion provides conclusive evidence of rupture of the ACL. A detailed study of pathological displacement is the basis for a classification of laxity. It is then possible to decide for each type of laxity, the surgical treatment which is specifically adapted to the lesion, and to define a reference value for judging outcome.     

A comparison of conservative and delayed surgical treatment of anterior cruciate ligament ruptures

Summary. A series of 60 matched and paired patients with complete rupture of the anterior cruciate ligament (ACL) was studied; 30 were treated conservatively, even though operation was recommended, and 30 were operated on within 35 months (range 18 to 48 months) after the ACL rupture. The average age was 34 years in each group. They were assessed 39 months after arthroscopy or reconstruction. At follow up, no patient had flexion of less than 100°, 13 of the reconstructed knees had an extension deficit, but in only one was this more than 10°. Thirty-six percent of the reconstructed and 14% of the conservatively treated patients graded their sports activity as unlimited, while 13% of the ACL reconstructions and 21% of those treated conservatively were severely limited. The Lysholm, Cincinnati and OAK scores were significantly better in the reconstructions. The anterior drawer sign was positive in 24% of the ACL reconstructions and in 81% of the conservatively treated patients; 19% had a positive pivot shift after reconstruction compared to 75% of those treated conservatively. Even though there was a considerable number of patients with a decreased range of motion after ACL reconstruction because of the slow regime of postoperative mobilisation used, the results of operation are significantly better than after conservative treatment even when ACL reconstruction was carried out late after injury.

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Résumé. 60 patients avec une rupture complète du ligament croisé antérieur furent traités soit conservativement (30) soit chirurgicalement (30) avec une transplantation os-tendon-os provenant du tiers médian de la rotule sous arthroscopie en moyenne 35 mois après la rupture. Dans les deux groupes l’age moyen était de 34 ans. Le flexion obtenue était toujours d’au moins 100 degrés, un déficit d’extension était noté chez 2 patients du groupe traité conservativement et chez 13 patients du groupe traité par reconstruction. L’activité sportive était illimitée chez 31 patients avec reconstruction et chez 14 patients traités conservativement. Les scores Lysholm, Cincinnati et OAK étaient meilleurs chez les patients traités par reconstruction. Un phénomène de pivot-shift était retrouvé dans 19% des cas de reconstruction et 75% des cas de traitement conservatif. Bien qu’un grand nombre de patients avait une diminution de la mobilité après reconstruction, les résultats du traitement chirurgical étaient significativement meilleurs qu’après traitement conservatif.

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Accepted: 27 October 1997     

Clinical diagnosis of an anterior cruciate ligament rupture: a meta-analysis

STUDY DESIGN: Meta-analysis. OBJECTIVES: To define the accuracy of clinical tests for assessing anterior cruciate ligament (ACL) ruptures. BACKGROUND: The cruciate ligaments, and especially the ACL, are among the most commonly injured structures of the knee. Given the increasing injury prevalence, there is undoubtedly a growing need for clinical decision making of health care providers. We reviewed the literature to analyze the diagnostic accuracy of the clinical examination for assessing ACL ruptures. METHODS AND MEASURES: MEDLINE (1966 to April 2005), EMBASE (1989 to April 2005), and CINAHL (1982 to April 2005) searches were performed. Also reference lists of the included studies were reviewed. Studies selected for data extraction were those that addressed the accuracy of at least 1 physical diagnostic test for ACL rupture and compared the performance of the clinical examination of the knee with a reference standard, such as arthroscopy, arthrotomy, or MRI. Searching was limited to English, German, and Dutch languages. RESULTS: Twenty-eight studies that assessed the accuracy of clinical tests for diagnosing ACL ruptures met the inclusion criteria. Study results were, however, heterogeneous. The Lachman test is the most valid test to determine ACL tears, showing a pooled sensitivity of 85% (95% confidence interval [CI], 83-87) and a pooled specificity of 94% (95% CI, 92-95). The pivot shift test is very specific, namely 98% (95% CI, 96-99), but has a poor sensitivity of 24% (95% CI, 21-27). The anterior drawer test shows good sensitivity and specificity in chronic conditions, respectively 92% (95% CI, 88-95) and 91% (95% CI, 87-94), but not in acute conditions. CONCLUSION: In case of suspected ACL injury it is recommended to perform the Lachman test. Because the pivot shift test is very specific both in acute as well as in chronic conditions, it is recommended to perform the pivot shift test as well.     

Simultaneous ipsilateral ruptures of the anterior cruciate ligament and patellar tendon: a case report

The simultaneous diagnosis of ipsilateral patellar tendon rupture and anterior cruciate ligament tear is rare. Surgical repair is complicated by different rehabilitation regimens as well as anterior cruciate ligament graft choices. We present a case where at the same operative setting, the patellar tendon was repaired, and the anterior cruciate ligament reconstructed with autologous hamstring graft.     

Instrumented Lachman tests for the evaluation of anterior laxity after reconstruction of the anterior cruciate ligament

Using a KT-1000 arthrometer, in fifty subjects were measured the anterior ligamentous laxity in a knee in which the anterior cruciate ligament had been reconstructed and in the normal, contralateral knee. We also determined the anterior tibial displacement and anterior compliance, using the Lachman test. The subjects were divided into groups according to the type of autogenous intra-articular substitute (either the central one-third of the patellar tendon or the semitendinosus tendon) that had been used for the anterior cruciate ligament and according to the duration of follow-up (range, twenty-four to 101 months). Lachman tests were performed, applying sixty-eight and ninety newtons of force, and indices for anterior compliance were calculated. Although significantly more anterior laxity was demonstrated with both sixty-eight and ninety newtons of force in the reconstructed knees than in the contralateral, normal knees (p less than 0.001), thirteen subjects, of whom eight lacked full extension of the reconstructed knee, had more anterior laxity in the normal knee. Analyses of variance showed no significant differences in the results of the Lachman tests as related to either the type of reconstruction or the length of postoperative follow-up. The results suggested that the two types of ligamentous substitute that were used in this study were equally efficient in limiting anterior tibial displacement, as demonstrated by the Lachman test. The study also demonstrated that the substitutes did not elongate significantly during the period of the study.     

Human knee joint sound during the Lachman test: Comparison between healthy and anterior cruciate ligament-deficient knees

Background

The Lachman test is clinically considered to be a reliable physical examination for anterior cruciate ligament (ACL) deficiency. However, the test involves subjective judgement of differences in tibial translation and endpoint quality. An auscultation system has been developed to allow assessment of the Lachman test. The knee joint sound during the Lachman test was analyzed using fast Fourier transformation. The purpose of the present study was to quantitatively evaluate knee joint sounds in healthy and ACL-deficient human knees.

Radiological sign of chronic anterior cruciate ligament deficiency

An early radiological sign of anterior cruciate ligament deficiency is described. A retrospective study of the radiographs of 38 patients with chronic anterior cruciate ligament deficiency was performed. In 36 patients from this group an osteophyte was present on the medial femoral condyle adjacent to the medial tibial spine. This was best seen on a 30 ° notch view and was the earliest radiographic sign of chronic anterior cruciate ligament deficiency.     

Biomechanical analysis of the ankle anterior drawer test for anterior talofibular ligament injuries

The effect of sectioning the anterior talofibular ligament on the load-displacemnt behavior of the ankle was evaluated in vitro during the anterior drawer test using the flexibility approach. Controlled forces were applied across the ankle joint in the anterior-posterior direction, and the resulting displacements were measured at four flexion angles (10° of dorsiflexion, neutral, and 10° and 20° of plantar flexion). The anterior talofibular ligament then was sectioned, and the anterior-posterior loadings were repeated at the four flexion angles. Two parameters were developed to describe the nonlinear load-displacemnt response of the ankle joint: neutral zone laxity (joint displacement between ± 2.5 N) and flexibility (a measure of the nonlinear load-displacement response of the ankle between 10 and 50 N of anterior drawer loading). After sectioning the anterior talofibular ligament, significant increases in neutral zone laxity were observed at all angles of ankle flexion. The largest increases in neutral zone laxity were found with the ankle in 10° of plantar flexion (76.3% increase) and 20° of plantar flexion (89.7% increase). After sectioning the ligament, a significant increase (19.3%) in flexibility of the ankle was observed at 10° of dorsiflexion, but no change in flexibility was observed with the ankle in the neutral and plantar flexed positions. These findings indicate that anterior drawer testing of the anterior talofibular ligament-deficient ankle between 10° and 20° of plantar flexion results in the largest increase in neutral zone laxity compared with the normal ankle with intact ligaments. They also suggest that an excessive magnitude of force during clinical application of the anterior drawer examination may not be needed to diagnose disruption of the anterior talofibular ligament.     

Repair of chronic ruptures of the anterior cruciate ligament using allograft reconstruction and a ligament augmentation device

A prospective study was performed to determine the effect of a ligament augmentation device (LAD) on the replacement of the anterior cruciate ligament (ACL) using tendon allografts. Twenty-five patients were followed for 66 to 98 months after tendon allograft replacement with LAD reinforcement for ACL rupture. The evaluation was done using the form of the International Knee Documentation Committee (IKDC), the Lysholm score and the Tegner scale. Two patients sustained a rerupture after major injury. Three other multiply-injured patients scored poorly because of associated injuries and fractures (IKDC grade D). Four patients scored normal (grade A), 12 patients nearly normal (grade B), and 5 patients abnormal (grade C). The Lysholm score showed 14 excellent (average 96), 5 good (average 86) and 4 fair results (average 76). Three patients with excellent results were IKDC grade C, solely because the xrays showed slight narrowing of the medial joint line, which might indeed indicate future problems. On the Tegner scale, the sports level decreased by an average of 1.4 points (from 7.25 to 5.83). Only five patients showed an anteroposterior displacement of more than 3 mm, of which only one was in the grade C group.     

Injury to the anterior cruciate ligament producing the pivot-shift sign

The clinical entity termed the pivot shift was studied in cadaver specimens and its significance was evaluated. It was found to be highly correlated with a tear of the anterior cruciate ligament, and it corresponded to a sudden anterior-internal rotation subluxation-dislocation of the tibia and posterior horn of the lateral meniscus beneath the lateral femoral condyle.     

The loss of extension test (LOE test): a new clinical sign for the anterior cruciate ligament insufficient knee

Background

This prospective study was created to evaluate the reliability of a new clinical test, which we termed the “loss of extension test” (LOE test). The LOE test investigates the loss of normal maximum passive extension (MPE) of the knee due to an anterior cruciate ligament tear in comparison to the normal MPE of the healthy knee.

Materials and methods

The study was divided into two consecutive parts. Part 1 was designed to assess the side-to-side difference in normal MPE in a healthy population. In part 1, 100 healthy adults were enrolled. Part 2 was designed to evaluate the LOE test reliability in injured knees. In part 2, we included 196 selected patients.

Results

In part 1, the average side-to-side difference in MPE in the healthy population was not statistically significant. In part 2, the overall average side-to-side difference in MPE of the injured group was 10.1 mm ± 14.1 (min −20; max 60), which was not statistically significant (p = 0.52). An anterior cruciate ligament (ACL) tear was found in 121 knees among 196 patients. The average side-to-side difference in MPE in the ACL-insufficient group was 16.9 mm ± 13.4 (min −20; max 60), which was statistically significant (p < 0.0001). The accuracy of the loss of extension test was 83.7 %, its specificity was 93.3 %, its sensitivity was 77.7 %, its positive predictive value was 95 %, and its negative predictive value was 72.2 %.

Conclusions

The reliability of the LOE test is comparable to those reported in the literature for the Lachman test and dynamic tests, so the LOE test could represent a useful tool for the diagnosis of the anterior cruciate ligament insufficient knee.     

Stability comparison of anterior cruciate ligament between double- and single-bundle reconstructions

The purpose of this study was to evaluate the intra-operative stability during double-bundle anterior cruciate ligament (ACL) reconstructions (20 knees) using a navigation system and compare the results with those obtained from single-bundle reconstructions (20 knees). After registering the reference points during ACL reconstruction, antero-posterior and rotational stability tests with 30° knee flexion using a navigation system were measured before and after reconstructions on both groups. The change of antero-posterior translation after and before reconstruction was 12.5 mm in the double-bundle group and 10.5 mm in the single-bundle group, showing significant inter-group difference (p=0.014, from 17.5 mm to 5.1 mm in the double-bundle and from 16.6 mm to 6.1 mm in the single-bundle group). The mean rotational stability of the double-bundle group also showed more significant improvement after reconstruction compared to that of the single-bundle group (9.8° in the double- and 5.6° in the single-bundle groups, p<0.001). These findings suggest that a double-bundle ACL reconstruction restores greater knee stability with respect to the antero-posterior and rotational stability than a single-bundle reconstruction.

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Résumé  Le propos de cette étude est d’évaluer la stabilité per opératoire de la reconstruction du ligament croisé antérieur par deux faisceaux à propos de 20 genoux avec utilisation d’un système de navigation. Ces résultats ont été comparés à ceux obtenus par une reconstruction par un seul faisceau (20 genoux). Après enregistrement des différents points de références, la stabilité des genoux est testée à 30° de flexion en utilisant le système de navigation avant et après la reconstruction dans les deux groupes. La modification de la translation antéro postérieure après et avant la reconstruction était de 12,5 mm dans le groupe à deux faisceaux et de 10,5 mm dans le groupe à un seul faisceau, montrant une différence significative (p=0,014, 17,5 mm à 5,1 mm dans les réfections avec deux faisceaux et de 16,6 mm à 6,1 mm dans les réfections à un seul faisceau). La stabilité en rotation a également été améliorée dans le groupe de reconstruction à deux faisceaux (9,8° contre 5,6° dans le groupe à un seul faisceau, p<0,001). Ces données confirment que la reconstruction des ligaments croisés antérieurs par la technique à deux faisceaux permet d’avoir un genou beaucoup plus stable tant sur le plan antéro postérieur que sur le plan rotatoire si l’on compare cette technique à celle de la reconstruction avec un seul faisceau.

     

Suture of fresh ruptures of the anterior cruciate ligament: A 5-year follow-up

Thirty-five of 41 consecutive patients were followed for 5 years after early primary suture of the acutely torn anterior cruciate ligament and repair of all other injured structures; three early failures were excluded from the series, and three patients were lost to follow-up.

Twenty-three of the patients also had an early follow-up 2 years postoperatively. From the early to the late follow-up, the function of the operated knees decreased significantly.     

Allograft reconstructions for chronic ruptures of the anterior cruciate ligament: augmentation versus non-augmentation

. A retrospective study was performed to determine the effect of a ligament augmentation device (LAD) combined with a tendon allograft for the treatment of chronic rupture of the anterior cruciate ligament (ACL). Fifty-four knees in 54 patients were divided into two groups. Group 1 consisted of 29 knees that were managed with a tibialis anterior allograft alone, and group 2 consisted of 25 knees that were managed with both the allograft and a Kennedy LAD. All patients were managed with the same post-operative programme of immediate motion and rehabilitation of the knee. Forty patients returned for evaluation at a mean of 84 months post-operatively. Results were evaluated with the International Knee Documentation Committee (IKDC) grades, the Lysholm score, and the Tegner scale. Use of the LAD did not improve reconstruction with regard to any of the individual variables of the overall score. Although the LAD reduced anterior-posterior displacement effectively for the first 20 weeks post-operatively, there was no difference between the groups in terms of the percentage of knees that had abnormal displacement at the latest follow-up. The overall rate of failure was 20% (8) of the 40 knees. Résumé. Nous avons effectué une étude rétrospective sur l'effet d'un renforcement ligamentaire synthétique (ligament augmentation device-LAD) sur le résultat des plasties du ligament croisé antérieur (LCA) par allogreffe. Cinquante-quatre patients ont été divisés en deux groupes. Le groupe 1 consistait de 29 genoux réparés par allogreffe et le groupe 2 consistait en 25 genoux réparés par allogreffe et LAD. Tous les patients ont re?us le même programme postopératoire de mobilisation immédiate. Quarante patients ont été revus avec un recul moyen de 84 mois. L'évaluation a été faite avec le document de l'International Knee Documentation Committee (IKDC), le score de Lysholm, et le score de Tegner. Les résultats des reconstructions par allogreffe et LAD n'étaient pas supérieurs par rapport aux reconstructions par allogreffe seule. Le déplacement antéro-postérieur diminuait effectivement pour les premières 20 semaines post-opératoires. Néanmoins, il n'y avait plus de différence entre le pourcentage de genoux des deux groupes ayant un déplacement anormal au dernier rappel. L'échec général était de 20% (8) sur 40 genoux.     

Acute isolated injury of the posterior cruciate ligament treated by a dynamic anterior drawer brace: a preliminary report

We investigated the role of a functional brace worn for four months in the treatment of patients with an acute isolated tear of the posterior cruciate ligament to determine whether reduction of the posterior tibial translation during the healing period would give an improved final position of the tibia. The initial and follow-up stability was tested by Rolimeter arthrometry and radiography. The clinical outcome was evaluated using the Lysholm score, the Tegner score and the International Knee Documentation Committee scoring system at follow-up at one and two years. In all, 21 patients were studied, 21 of whom had completed one-year and 17 a two-year follow-up. The initial mean posterior sag (Rolimeter measurement) of 7.1 mm (5 to 10) was significantly reduced after 12 months to a mean of 2.3 mm (0 to 6, p < 0.001) and to a mean of 3.2 mm (2 to 7, p = 0.001) after 24 months. Radiological measurement gave similar results. The mean pre-injury Lysholm score was normal at 98 (95 to 100). At follow-up, a slight decrease in the mean values was observed to 94.0 (79 to 100, p = 0.001) at one year and 94.0 (88 to 100, p = 0.027, at two years). We concluded that the posterior cruciate ligament has an intrinsic healing capacity and, if the posteriorly translated tibia is reduced to a physiological position, it can heal with less attentuation. The applied treatment produces a good to excellent functional result.