Anterior subluxation of the lateral tibial plateau. A diagnostic test and operative repair

The pivot shift

The Lachman and the pivot shift are the two clinical tests most commonly used to assess instability in the anterior cruciate ligament (ACL)-deficient knee. Because it is quantifiable, the Lachman test has become the benchmark for assessing the success of ACL reconstruction. As a result, surgical techniques have been developed that effectively eliminate anterior laxity of the knee. Recent studies have shown, however, that rotational stability is not always restored after ACL reconstruction. Furthermore, there is mounting evidence that the pivot shift examination correlates with functional instability and patient outcomes better than does any other physical examination test. This test attempts to reproduce the functional combined rotary and translational instability in the ACL-deficient knee. Although the pathologic kinematics of the pivot shift are difficult to measure, recent technological advances have allowed more accurate and objective descriptions of the pivot shift, which have furthered our understanding of the complex motions involved. These advances may lead to a method of quantifying the pivot shift for research purposes and, ultimately, to ACL reconstruction that is tailored specifically to each patient's objectively measured rotational instability.

Arthroscopic treatment of a large lateral femoral notch in acute anterior cruciate ligament tear

A 24-year-old professional soccer player suffered an acute anterior cruciate ligament tear associated with a radiologically evident impression fracture of the lateral femoral condyle, the so-called "lateral femoral notch sign". Following MRI validation of the injury with detection of an additional lateral meniscus tear, arthroscopy was carried out 3 days after the injury. Due to the extended impression of about 5 mm, arthroscopically assisted closed reduction of the depression fracture was performed. A 3.2 mm tunnel was drilled at the lateral femoral condyle in a supero-inferior direction using an ACL tibial guide and the depressed area could be restored using an elevator. The resulting subchondral bone defect in the femoral condyle was filled with freeze-dried human cancellous bone allograft. As a one-stage procedure ACL reconstruction was carried out using a hamstring tendon technique. At 1-year follow up the patient has returned to full sporting function, including playing soccer with a radiographically reduced lateral femoral notch sign.

Contributory factors to the results of gravity-assisted pivot-shift test for anterior cruciate ligament injury: the significance of muscle torque around the knee

Gravity-assisted pivot-shift (GAPS) test is a newly advocated test for anterior cruciate ligament (ACL) injury. It induces anterolateral rotatory instability with valgus stress to the knee applied by gravitational force during patient's active knee motion. We investigated prospectively the relationships between the results of the GAPS test and the possible contributory factors and sought to clarify the determinant factors of the GAPS test. A total of 54 knee joints of 54 patients with unilateral ACL injury (29 males, 25 females, average 23.4 +/- 9.0 years old) were enrolled in this study and were divided into two groups, i.e., positive GAPS test group and negative GAPS test group. Muscle torque around the knee joints measured before surgery, configuration of the femoral condyle and tibial posterior slope angle measured on lateral radiograph, and other clinical factors were compared between the two groups using Mann-Whitney U test or chi-square test. According to the results of these analyses, factors having a statistically significant difference were additionally evaluated using multiple logistic regression analysis to reveal items with strong relevance to a positive GAPS test. The results of the multiple logistic regression analysis showed that the flexor/extensor peak torque ratio of contralateral uninjured knees and sex had a significant correlation with the results of the GAPS test. The relatively less flexor muscle torque compared with extensor muscle torque, and being a female patient were considered to be the determinant factors of a positive GAPS test.

Current concepts review: comprehensive physical examination for instability of the knee

A careful history and physical examination are the cornerstones of orthopaedic sports medicine. When evaluating a patient for ligamentous instability of the knee joint, an understanding of the contribution of anatomic structures to stability enhances a practitioner's ability to achieve an accurate clinical diagnosis. This article reviews the various types of knee instability and the associated anatomic structures. Ultimately, information must be obtained from multiple tests to reach the final diagnosis. We describe in detail the pathologic and biomechanical basis of the tests for both tibiofemoral and patellofemoral instability of the knee joint and provide recommendations for performance and interpretation of these physical examinations.

Influence d’une ligamentoplastie extra-articulaire latérale sur les résultats de la reconstruction du ligament croisé antérieur avec le ligament patellaire avec 7 ans de recul

PURPOSE OF THE STUDY

Reconstruction of the anterior cruciate ligament (ACL) is a common procedure, but use of lateral reinforcement is still a subject of debate. The purpose of this study was to compare two randomized series of ACL reconstructions, one using an intra-articular method (patellar tendon autograft) and the other an intra- and extra-articular method (Mac-InJones).

MATERIAL AND METHODS

From January 1995 to March 1998, 63 knees underwent surgery for ACL reconstruction. Inclusion criteria was significant medial differential laxity measured between 7 and 12 mm on passive dynamic x-rays as 20 degrees flexion. Group 1 (patellar tendon intra-articular reconstruction) included 34 patients (27.1+/-7.5 years) and group 2 (intra-articular reconstruction plus extra-articular quadircipital tendon plasty) included 29 patients (28.5+/-12 years). The IKDC score was determined for 72% of the knees in group 1 and 68% in group 2 at seven years follow-up on average (102 and 93 months respectively). Anterior laxity was measured radiographically and with KT-1000. The position of the tunnels was controlled using the Aglietti method.

RESULTS

The subjective functional score was 83.6+/-3.5 in group 1 and 83.5+/-3.5 in group 2. The overall IKDC knee score classes for group 1 were 0% A, 52.4% B, 28.6% C, and 19% D and for group 2 were 5.5% group A, 50% group B, 33.3% group C, and 11.1% group D. In group 1, the pivot test was negative in 61.9% and noted stage 1 in 28.6% and stage 2 in 9.5%. In group 2, the pivot test was negative in 78.9% and noted stage 1 in 15.8% and stage 2 in 5.3%. The KT-1000 showed no difference in gain in laxity: 31% for group 1 and 27% for group 2. Similarly, radiographically there was no difference with a 43.9% gain in differential laxity for the medial compartment and 45.3% for the lateral compartment in group 1. In group 2 the corresponding values were 51.9% and 41.8%. The position of the tunnels was the same in the two groups.

DISCUSSION

In a preliminary study with two years follow-up, the results in these two series were not significantly different. It was concluded that there was not clear advantage to adding the extra-articular lateral plasty. At the present 7-year follow-up, pivoting appears to be better controlled in the lateral plasty group (p=0.23), but with no significant difference for laxity for both knee compartments. The inclusion criteria would be different today and would be based on the laxity of the lateral compartment.

Gravity-assisted pivot-shift test for anterior cruciate ligament injury: a new procedure to detect anterolateral rotatory instability of the knee joint

The denominated gravity-assisted pivot-shift test was introduced as a new procedure to detect anterolateral rotatory instability of the knee joint. The patient lies in the supine position or slightly rotated onto the affected side. The affected knee flexed approximately 60 degrees and the ipsilateral hip flexed, abducted and externally rotated so that the plane of the knee motion runs parallel to the floor. The examiner instructs the patient to raise the affected leg off the examining table and to extend the affected knee gradually. If the lower leg is internally rotated suddenly, with the knee subluxated at an angle of approximately 20 degrees , followed by the reduction in flexion, this test is regarded as positive. This test was investigated on 51 anterior cruciate ligament (ACL) deficient knees, being positive in 30 knees (Group P) and negative in 21 (Group N) with the positive rate of 59%. There was no significant correlation between the result of this test and the clinical features, but Group N included relatively small number of females and recurrent injuries tended to occur more frequently in Group P. Thirty-six knees received ACL reconstruction subsequently. There was no statistically significant difference between the groups in the side-to-side difference in anterior knee laxity at one year postoperatively. However, three patients with the side-to side difference of more than 3 mm belonged to Group P. Relatively low positive rate in ACL deficient knees suggests that it may not be used as a diagnostic procedure for ACL injury. It is possibly used for the prediction of high risk patients for symptomatic giving-way and/or patients with poor prognosis after ACL reconstruction.

Implications of the pivot shift in the ACL-deficient knee

The Losee repair controls rotational subluxation of the lateral femoral condyle, or pivot shift, but does not reliably eliminate Lachman laxity. Despite this surgical limitation, many patients who were operated on continued to do high-demand activities at the last followup. We hypothesized that Lachman findings alone did not predict poor surgical outcome or progression to osteoarthritis. We report on 87 patients evaluated at an average of 9 years (range, 5-21 years) postoperatively. Prospectively collected examinations and radiographic, subjective, and objective outcome measures were recorded and statistically evaluated. The presence of a postoperative pivot shift or residual varus laxity correlated with poor patient subjective evaluations and poor scoring outcomes. Lachman laxity with an absent pivot shift had no correlation with the outcome measures or onset of radiographic progression to osteoarthritis. Meniscectomy, additional knee surgery, increased valgus or varus laxity, and time from injury until the final radiograph positively correlated with the onset of osteoarthritis. Elimination of the pivot shift was necessary to achieve successful relief of symptoms and functional outcome. In the absence of a pivot shift, Lachman laxity was not solely predictive of poor outcomes.

LEVEL OF EVIDENCE

Prognostic study, Level II-1 (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Reinforced iliotibial tenodesis for chronic anterolateral instability of the knee: a 6-year follow-up

Reinforced iliotibial tenodesis is an extra-articular procedure to eliminate anterolateral instability of an anterior cruciate ligament-deficient knee. The procedure carries a low complication rate and offers an easy rehabilitation program. This study evaluated the use of reinforced iliotibial tenodesis in a select group of 52 patients with a mean age of 41 years (range: 38-50 years). Obese patients, professional athletes, and patients with more complex injuries (eg, concomitant posterior cruciate or medial collateral ligament injuries) were excluded. Results are encouraging after a mean follow-up of 6 years (range: 2-10 years). Although 24 patients had a positive anterior drawer or Lachman test, none had a positive pivot test. In addition, all patients reported giving way was eliminated after surgery.

Aggressive quadriceps loading can induce noncontact anterior cruciate ligament injury

BACKGROUND

The force responsible for noncontact anterior cruciate ligament (ACL) injuries remains controversial. The patella tendon to tibial shaft angle causes an anterior tibial shear force with quadriceps activation.

HYPOTHESIS

An aggressive quadriceps contraction can injure the ACL.

METHODS

The authors characterized noncontact ACL injury and kinematics with aggressive quadriceps loading. Thirteen fresh-frozen knees were potted in a jig held in 20 degrees of flexion while a 4500 N quadriceps contraction was simulated. Knee kinematics were recorded. A KT-1000 arthrometer and a simulated active quadriceps test assessed anterior displacement. Statistics were performed using paired t tests and 1-way analysis of variance.

RESULTS

Kinematics revealed the following mean values: anterior displacement, 19.5 mm; valgus, 2.3 degrees; and internal rotation, 5.5 degrees. Mean KT-1000 and active quadriceps test differences were 4.0 mm and 2.7 mm, respectively (statistically significant P =.002 and P =.002). Six knees showed gross ACL injury at the femoral insertion. Based on ACL injury, KT-1000 differences were statistically significant (P =.029).

CONCLUSIONS

Aggressive quadriceps loading, with the knee in slight flexion, produces significant anterior tibial translation and ACL injury. This suggests that the quadriceps is the intrinsic force in noncontact ACL injuries, producing a model for further investigation.

Clinical examination of the knee following trauma: an evidence-based perspective

The knee is a common site of injury. The increasing number of clinical tests and greater understanding of the joints biomechanics, lead to difficulties in both the interpretation of the clinical examination and in the reliance that should be placed on specific signs or tests. This article helps review the present evidence surrounding examination of the knee. This will enable clarification of which tests are most appropriate to be applied for specific injuries, and how they should be interpreted by the clinician. The most accurate test currently is that for anterior cruciate ligament deficiency as described by Lachman. Other classically taught tests, such as that of McMurray for meniscal tears, have been demonstrated to be of poor sensitivity and specificity.

Abnormal lateral notch in knees with anterior cruciate ligament injury

We reviewed plain radiograms of anterior cruciate ligament injuries to determine the frequency of an abnormal lateral notch found in the lateral femoral condyle, and we investigated a possible mechanism for its occurrence by determining the relationship with associated injuries. We analyzed data for 216 patients who underwent ACL reconstruction between 1993 and 1996, whose radiographic images of the contralateral knee were available. The numbers of male and female patients were 122 and 94, respectively, and their ages ranged from 14 to 47 years (average, 25 years). The abnormal notch visualized by lateral radiograph was found in 66 of 216 knees (30. 6%) and was classified into three types. The type of abnormal notch seen most frequently (73%) was located at the same site as the notch on the contralateral side, but appeared deeper than normal. Knees with abnormal notches showed lateral meniscal injuries more frequently than those without such notches (P<0.005). The abnormal notch was assumed to have formed at the time of injuries, after impingement of the lateral femoral condyle on the lateral tibial condyle. Cartilage damage at the abnormal notch should be carefully observed in the future.

Passive terminal extension causes anterior tibial translation in some anterior cruciate ligament-deficient knees

The purpose of the present study was to accurately measure anterior tibial translation during passive terminal extension (ATT-PTE) in anterior cruciate ligament (ACL)-deficient knees, and to investigate correlations between various characteristics of such knees and the magnitude of ATT-PTE. The subjects were 79 patients with unilateral ACL-deficient knees and little flexion contracture. All patients were confirmed to have ACL injury of one knee by arthroscopy. Lateral radiographs of the bilateral knees in passive terminal extension were compared, and ATT-PTE was measured using an original superimposition method. The inter-observer and intra-observer reproducibility of measurement was significantly greater for this method than for the method without superimposition. In 42 of the 79 patients (53%), ATT-PTE was greater than 1 mm, while it was greater than 4 mm in 15 patients (19%). ATT-PTE was significantly larger in patients with a large anterior displacement difference (as measured with the KT-1000 arthrometer) (ATT-KT), a long period since injury, a history of reinjury, injury to the meniscus, and the presence of gross pivot shift. On the other hand, ATT-KT was equal to or greater than 2.5 mm in all 79 patients and showed no significant correlation with the time since initial injury, history of reinjury, on injury to the meniscus.

Long-term results of anterior cruciate ligament reconstruction using ilio-tibial tract and semitendinosis tendon

During the 3-year period from June 1984 to July 1987, 115 anterior cruciate ligament reconstructions were performed by a combined intra- and extra-articular technique using the anterior three-quarters of the ilio-tibial band and the semitendinosis tendon. Post-operative rehabilitation included limited mobilization in flexion for 6 weeks post-surgery. Eighty-four knees (78% follow-up) were reviewed at a mean of 8 years (range 6.3-9.7 years). The long-term results of surgery were assessed using the Lysholm score, Noyes activity rating, the International Knee Documentation Committee (IKDC) knee ligament standard evaluation and manual maximum KT-1000 side-to-side difference measurements were made. In addition 45 knees were examined radiographically. Reconstruction within 6 weeks of injury led to a significantly higher chance of concurrent meniscal trauma being suitable for repair (P=0.002). At early reconstruction coincidental macroscopic chondral damage was noted in 23% and limited to the patella while at delayed reconstruction 45% of knees showed chondral damage which also involved tibio-femoral compartments in some cases. Overall 87% returned to their pre-injury sporting level and only one ceased through knee problems. Ninety-three percent had a manual maximum KT-1000 side-to-side difference at final review no greater than 3 mm. The Lysholm score rated results as 91% excellent or good while the overall IKDC evaluated 85% as normal or near normal, 14% abnormal and 1% (one case) as severely abnormal. Twenty-seven percent of acute and 10% of delayed reconstructions developed some degree of arthrofibrosis (P=0.049) and this significantly predisposed the knee to early degenerative change (P=0.002).

Anterior cruciate ligament reconstruction in adolescents with open physes

The purpose of this study was to evaluate anterior cruciate ligament reconstructions performed in adolescents with open physes and a skeletal age of at least 14 years. At one center, from 1992 to 1996, 19 adolescents (ages, 11 to 15 years) with open physes and a skeletal age of at least 14 years underwent arthroscopic anterior cruciate ligament reconstruction using an Achilles tendon allograft placed through drill holes across the open physes in both the distal femur and proximal tibia. Fifteen patients returned for reevaluation at an average of 25 months postoperatively (range, 12 to 60 months); the remaining four patients were interviewed by telephone. There were no significant leg-length discrepancies or angular deformities as determined by scanograms and anteroposterior and lateral radiographs of the femur and tibia. The mean Lysholm knee score was 97 (range, 94 to 100) and the mean KT-1000 arthrometer side-to-side difference at 20 pounds of anterior force was 1.7 mm (range, 0.0 to 3.0). All patients were satisfied with the results of surgery, and 16 of 19 patients returned to the same sport they were participating in before the injury. This study demonstrates that anterior cruciate ligament reconstruction using an Achilles tendon allograft is a viable treatment option for skeletally immature patients with a skeletal age of 14 years who have sustained midsubstance tears of the anterior cruciate ligament.

Significance of changes in the reference position for measurements of tibial translation and diagnosis of cruciate ligament deficiency

Measurements of tibial translation in response to an external load are used in clinical and laboratory settings to diagnose and characterize knee-ligament injuries. Before these measurements can be quantified, a reference position of the knee must be established (defined as the position of the knee with no external forces or moments applied). The objective of this study was to determine the effects of cruciate ligament deficiency on this reference position and on subsequent measurements of tibial translation and, in so doing, to establish a standard of kinematic measurement for future biomechanical studies. Thirty-six human cadaveric knees were studied with a robotic/universal force-moment sensor testing system. The reference positions of the intact and posterior cruciate ligament-deficient knees of 18 specimens were determined at full extension and at 30, 60, 90, and 120 degrees of flexion, and the remaining five-degree-of-freedom knee motion was unrestricted. Subsequently, under a 134-N anterior-posterior load, the resulting knee kinematics were measured with respect to the reference positions of the intact and posterior cruciate ligament-deficient knees. With posterior cruciate ligament deficiency, the reference position of the knee moved significantly in the posterior direction, reaching a maximal shift of 9.3 +/- 3.8 mm at 90 degrees of flexion. For the posterior cruciate ligament-deficient knee, posterior tibial translation ranged from 13.0 +/- 3.4 to 17.7 +/- 3.6 mm at 30 and 90 degrees, respectively, when measured with respect to the reference positions of the intact knee. When measured with respect to the reference positions of the posterior cruciate ligament-deficient knee, these values were significantly lower, ranging from 11.7 +/- 4.3 mm at 30 degrees of knee flexion to 8.4 +/- 4.8 mm at 90 degrees. A similar protocol was performed to study the effects of anterior cruciate ligament deficiency on 18 additional knees. With anterior cruciate ligament deficiency, only a very small anterior shift in the reference position was observed. Overall, this shift did not significantly affect measurements of tibial translation in the anterior cruciate ligament-deficient knee. Thus, when the tibial translation in the posterior cruciate ligament-injured knee is measured when the reference position of the intact knee is not available, errors can occur and the measurement may not completely reflect the significance of posterior cruciate ligament deficiency. However, there should be less corresponding error when measuring the tibial translation of the anterior cruciate ligament-injured knee because the shift in reference position with anterior cruciate ligament deficiency is too small to be significant. We therefore recommend that in the clinical setting, where the reference position of the knee changes with injury, comparison of total anterior-posterior translation with that of the uninjured knee can be a more reproducible and accurate measurement for assessing cruciate-ligament injury, especially in posterior cruciate ligament-injured knees. Similarly, in biomechanical testing where tibial translations are often reported for the ligament-deficient and reconstructed knees, a fixed reference position should be chosen when measuring knee kinematics. If such a standard is set, measurements of knee kinematics will more accurately reflect the altered condition of the knee and allow valid comparisons between studies.

The lateral notch sign associated with acute anterior cruciate ligament disruption

We prospectively studied all of the patients with anterior cruciate ligament disruptions who sought treatment at the senior author's office during a 36-month period. Plain radiographs identified depressions measuring 2 mm or more in the lateral femoral condyle (lateral notch sign) in 9 of 120 knees (7.5%) with acute anterior cruciate ligament disruption and in 2 of 44 knees (4.5%) with chronic pivot shift instability. The depression ranged from 2 to 6 mm deep and from 20 to 25 mm long. The mean age for acutely injured patients with lateral notch signs was 17.2 years, 6 years younger than the mean age of the group with acutely injured anterior cruciate ligaments as a whole. Ten of the 11 patients (91%) with lateral notch signs were men, and all 6 patients with depressions shallower than prior descriptions of the notch sign were men. In contrast, 67% (N = 110) of the entire group of patients who had anterior cruciate ligament disruption were men. Ten of the 11 patients (91%) with the lateral notch signs and 4 of the 6 patients (66%) with minimal depressions also had lateral meniscus tears, while 58 of 147 patients (39%) without lateral femoral condyle depression had lateral meniscus tears. Previous reports that the lateral notch is a sign of chronic anterior cruciate ligament deficiency with recurrent pivot shifts are not supported by the number of prospectively recognized acute lateral femoral notch signs in this series. We found the presence of radiographic changes in the lateral femoral condyle to have statistically significant correlations with young age, male sex, lateral meniscus tears in general and anterior-horn lateral meniscus tears specifically, and lateral femoral chondral lesions.

Technical pitfalls of collateral ligament surgery

The technical pitfalls of collateral ligament surgery include: Failure to properly diagnose and appropriately recommend surgery; posterolateral instability is the most commonly missed acute associated instability pattern Failure to correct all components of the injury (see Table 1): lateral meniscus, arcuate ligament, and popliteus, lateral gastrocnemius, and biceps muscles Failure to properly reattach and repair the damaged structures Peroneal nerve damage during the surgical approach and repair Wound problems: breakdown, hematoma Loss of motion This article presented a concise introduction to the anatomy of the collateral and capsular ligaments of the knee. This information should prove valuable in avoiding pitfalls in the diagnostic and surgical approach to the knee. To fully appreciate the anatomy, one must study it in the anatomy laboratory by performing repeated dissections. Only then can one appreciate how beautifully all of the structures function in unison. Application of this knowledge will help surgeons continue to improve and refine their approach to knee injuries.

Single versus two-incision arthroscopic anterior cruciate ligament reconstruction

The purpose of this study was to compare single (endoscopic) versus two-incision arthroscopic anterior cruciate ligament reconstruction using bone-patellar tendon-bone in a population of young athletes. All patients followed a similar postoperative rehabilitation program. The Lysholm knee score, the International Knee Documentation Committee Score, KT-1000 arthrometric measurements, Lachman tests, pivot shift tests, isokinetic and functional testing, and perioperative complications were used to compare the two techniques. Anteroposterior and lateral radiographs were also evaluated and compared. Group I comprised 51 patients who underwent two-incision arthroscopic ACL reconstruction. The average age was 19.8 years, with a range of 18 to 22. The average follow-up in this group was 31 months (range, 24 to 43 months). Group II, the endoscopic group, consisted of 31 patients with an average age of 19.4 years (range, 18 to 22). The average follow-up was 25 months (range, 24 to 31 months). There were no significant differences between the two groups using subjective, objective, and functional criteria. There did appear to be a trend toward a residual pivot glide in the endoscopic group, but this did not achieve statistical significance. Radiographic analysis demonstrated an increased incidence of screw divergence in the endoscopic group. Intraoperative complications were more common with the endoscopic method.

Anterior cruciate ligament surgery 1996. State of the art?

During the past 20 years, numerous basic science and clinical studies have improved the treatment of the anterior cruciate ligament deficient knee. As our understanding of the short term and long term morbidity caused by the torn anterior cruciate ligament has improved, and the morbidity of surgical reconstruction has decreased, the indications for anterior cruciate ligament reconstruction have widened. Anatomic placement of the anterior cruciate ligament graft has improved the outcome of surgery, although various techniques are used to achieve that goal. The patellar tendon autograft has been established as the gold standard graft choice, but several graft choices are available, and have given similar results in early followup. One of the major advances in anterior cruciate ligament reconstruction has been the acceptance of early range of motion and controlled endurance and strength training during the postoperative period.

The diagnostic accuracy of history, physical examination, and radiographs in the evaluation of traumatic knee disorders

We prospectively looked at the diagnostic accuracy of clinical examination of the knee in patients with arthroscopically documented knee injuries. The study included 156 patients with 156 knee injuries (72 acute and 84 chronic) who were seen during 1 year at Martin Army Hospital at Fort Benning Georgia. All patients were given a primary diagnosis based on their history, physical examination, and routine radiographs. Fifty-seven patients were also given one or more secondary diagnoses. Magnetic resonance imaging scans and arthrograms were not used in the evaluation of these patients. The primary diagnosis was correct in 83% of the knees. Of 57 secondary diagnoses given, 54% were correct and 31% were incomplete. An incorrect diagnosis was made in 14% of knees for both primary and secondary diagnoses. There were four patients with no identifiable lesion other than synovitis. With the increasing cost of medical care, the need for expensive diagnostic studies such as magnetic resonance imaging needs to be evaluated. The cost of a magnetic resonance image scan ranges between $600 to $1200 depending on the institution. The use of magnetic resonance imaging as a routine diagnostic aid in the clinical examination of the knee is unnecessary. Arthroscopic surgery of the knee should be based on the patient's history, physical examination, and radiographs.

Historical overview of operations for anterior cruciate ligament rupture

The evolution of the surgical management of anterior cruciate ligament rupture is critically reviewed. Special attention is paid to obsolete techniques or concepts which were once accepted with enthusiasm and important work that passed unnoticed.

Posterolateral arthritis of the knee

Arthritis in the posterolateral quadrant of the knee presents typical arthroscopic findings. With careful history, physical examination, and appropriate radiographs, it can be an office diagnosis. The history, physical findings, and arthroscopic findings in 15 patients with this problem were reviewed. Symptoms of posterolateral pain, give-way, and pain with stairclimbing were common. The only frequent physical findings were those of pain with the lateral meniscal entrapment test or pain with the pivot shift test. No ligamentous instability was noted. Weight-bearing radiographs demonstrated severe lateral chondral loss in flexion, but not in extension. Arthroscopic findings were typical. Previous injury to the posterior portion of the lateral meniscus was common. This seems to be a traumatic, rather than a degenerative, process. Three patients had varus-producing osteotomy of the distal femur. This was not effective in relieving their symptoms.

Reconstruction of old anterior cruciate ligament injuries. No difference between the Kennedy LAD-method and traditional patellar tendon graft in a prospective randomized study of 40 patients with 4-year follow-up

In a prospective randomized study we investigated 40 patients with functional instability due to old anterior cruciate ligament tears by using two different techniques for reconstruction of the ligament. 20 patients were randomized to reconstruction with use of a traditional medial bone-patellar tendon graft and 20 patients to a half-thickness patellar tendon graft augmented with the Kennedy Ligament Augmentation Device (LAD). At follow-up after 4 years, both groups were still improved concerning function scores and arthrometry. The use of the Kennedy LAD method, however, gave no more subjective or objective benefits than did the traditional method.

Arthroscopy-assisted anterior cruciate ligament reconstruction using patellar tendon substitution. Two- to four-year follow-up results

The purpose of this retrospective study was to evaluate clinically, functionally, and objectively our initial experience using free, autogenous middle third patellar tendon for anterior cruciate ligament reconstruction without extraarticular augmentation in 62 of 75 patients (80% followup) who were available for clinical review at a minimum 2-year followup. Subjective, clinical, functional, Cybex dynamometer, and KT-1000 arthrometer tests were performed along with modified tests of the Hospital for Special Surgery, Noyes Cincinnati, Tegner, and Lysholm knee rating scales. Ninety-two percent had a negative pivot shift at followup. The mean Cybex dynamometer extension deficits postoperatively were 9% and 7% at 180 and 240 deg/sec. Mild patellar pain symptoms were noted in 18%. The reoperation rate was 10% with a mild flexion contracture as the most common reason. The Hospital for Special Surgery scoring scale postoperatively was 88; Noyes, 86; Lysholm, 88; and Tegner, 6. Mean postoperative single-legged and vertical jump indices were 88% and 87%, respectively. The KT-1000 arthrometric evaluation postoperatively revealed a mean maximum manual difference of 0.3 mm; 92% of the patients had a maximum manual difference of < or = 3 mm. Subjectively, 95% indicated that they would undergo the procedure again. Early results demonstrate excellent stability, preservation of motion, and encouraging evaluations by scoring scales and arthrometric evaluation.

Anterior cruciate ligament reconstruction using the semitendinosus and gracilis tendons augmented by the losee iliotibial band tenodesis. A long-term study

Seventy patients were evaluated after combined intra- and extraarticular reconstruction of the anterior cruciate ligament. Semitendinosus and gracilis tendons were used for the intraarticular reconstruction and Losee iliotibial band tenodesis for the extraarticular procedure. Minimum followup was 5 years (average, 7). Clinical examination and instrumented ligament examination with the KT-1000 arthrometer and the Cybex II dynamometer were used to evaluate results. Subjectively, patients had no complaints of instability with daily activities; 93% had no complaints of instability with athletic participation. Clinical examination demonstrated that 81% had less than a 1 + Lachman test; 98% had a negative pivot shift. Instrumented examination of the anteroposterior limits of motion revealed that only 57% had less than 3-mm side-to-side difference; 30% had 3- to 5-mm; and 13% had 6- to 9-mm. Mean hamstring muscle strength measured with the Cybex II dynamometer was 94% at 60 and 96% at 100 deg/sec. When evaluated with the Zarins scale, 90% were rated good or excellent, 6% fair, and 4% poor. This reconstructive procedure restores functional, but not necessarily normal, stability in most anterior cruciate ligament-deficient knees. It allows patients to increase activity levels without significant risk of additional injuries.

Extra-articular tenodesis for anterior cruciate ligament rupture in amateur skiers

Thirty one amateur skiers with 33 knees which had had a symptomatic chronic rupture of the anterior cruciate ligament (ACL) treated with the Lemaire operation were reviewed retrospectively at an average of 4.5 years. Of the patients 23 were women. The operation failed to control symptoms in 17 out of the 33 knees. However the operation did control symptoms in 13 out of 19 knees in patients over 35 years old, compared with only three out of 14 knees in patients under 35 years old. Clinical and objective testing however showed that most knees were still unstable. Despite this 21 patients continued skiing. One patient with a successful result switched to playing tennis. Five patients gave up all sports. Four further patients, all under 35 years old, returned to skiing after an additional intra-articular reconstruction of the anterior cruciate ligament. An isolated extra-articular procedure in amateur skiers under 35 years old with symptomatic chronic ACL rupture is not recommended. They need at least an intra-articular reconstruction to control their symptoms and to stabilize the knee.

The accuracy of the clinical knee examination documented by arthroscopy. A prospective study

The diagnostic accuracy of the clinical examination for intraarticular injuries of the knee was documented by arthroscopy over a 6-month period. Two-hundred ninety patients (296 knees) were evaluated by history, physical examination, and standard radiographs. Supplemental diagnostic studies included 41 magnetic resonance images, 2 arthrograms, and 1 previous arthroscopy that had been recently performed. Overall, the correct diagnosis was made in 165 knees (56%), an incomplete diagnosis in 92 (31%), and an incorrect diagnosis in 39 (13%). There were only 2 knees (0.07%) with no discernable lesions. When a single lesion was present in the knee, the diagnosis was made correctly in 72% of cases. When more than 2 were discovered, the diagnosis was correct in only 30%. However, all individual lesions were diagnosed with an accuracy of greater than 90%. The lesions most difficult to diagnose were chondral fractures, fibrotic fat pads, tears in the anterior cruciate ligament, and loose bodies. Knees with acute lesions and those with a single diagnosis proved to be significantly easier to diagnose (P < 0.01). The variables that proved to be insignificant were age, sex, magnetic resonance imaging, surgeon, workers' compensation, or pending litigation.

Isolated posterior cruciate ligament reconstruction. Long-term results

From 1973 to 1987, 28 patients seen at our institution sustained isolated posterior cruciate ligament tears. Of these 28 patients, 25 were reevaluated at an average followup of 7 years and 1 month after secondary reconstruction of the posterior cruciate ligament using the semitendinosus and gracilis tendons alone or with an extraarticular procedure. Subjectively, 22 of 25 patients related no restrictions regarding activities of daily living, with 14 of 25 patients being able to return to their previous competitive level in sports. Objective evaluation after reconstruction revealed no change in the preoperative and postoperative posterior drawer examination in 13 of 25 patients, a finding confirmed by KT-1000 arthrometer measurements. Radiographic evaluation revealed degenerative changes predominantly involving the medial and patellofemoral compartments in 15 of 25 patients. Despite optimistic subjective reporting, this long-term retrospective study reveals that this procedure inconsistently limits posterior instability and therefore cannot be recommended.

High tibial osteotomy and ligament reconstruction in varus angulated, anterior cruciate ligament-deficient knees. A two- to seven-year follow-up study

We assessed short-term treatment results of younger patients with varus malalignment and chronic anterior cruciate ligament deficiency. Forty-one patients (mean, 32 years; range, 16 to 47) underwent a high tibial osteotomy. Because of giving way symptoms, 14 also had a lateral iliotibial band extraarticular procedure at the time of the osteotomy and 16 had an intraarticular anterior cruciate ligament allograft reconstruction after the osteotomy. All returned for followup (mean, 58 months; range, 23 to 86), which included KT-1000 arthrometer testing and evaluation by our knee rating system. Statistically significant (P < 0.05) improvements were found in the mean overall rating scores for pain, swelling, and giving way. Preoperatively, 30 (73%) had pain with activities of daily living or with any sports activity; 11 (27%) could perform only light sports activities without pain. At followup, 32 patients (78%) had no pain with activities of daily living or light sports. Ten of 15 patients with advanced medial tibiofemoral arthrosis (subchondral bone exposure) had significant improvements in symptoms. Patient satisfaction was high: 88% stated they would undergo the procedure again and 78% felt their knee condition was improved. Patients who had the allograft reconstruction had significantly lower (P < 0.05) anterior-posterior displacements at followup than those who had the extraarticular procedure. We concluded that osteotomy should be performed early in the disease process for younger athletes who experience symptoms with activity. It may be unrealistic, however, to expect continuation of sports beyond light recreational, given the joint arthrosis that is usually present and the high in vivo joint loadings with athletes. Anterior cruciate ligament reconstruction should be considered when giving way previously occurred and the patient plans to resume athletics. However, patients with advanced arthrosis can avoid anterior cruciate ligament surgery by reducing athletic activities.

How iliotibial tract injuries of the knee combine with acute anterior cruciate ligament tears to influence abnormal anterior tibial displacement

A knowledge of the patterns of injury to the components of the iliotibial tract allows a clearer interpretation of motion limits testing in patients with abnormal anterior tibial translation of the knee (anterior cruciate ligament-deficient knees). Eighty-two consecutive patients with acute knee injuries were classified as anteromedial-anterolateral rotatory instability (anterior cruciate ligament-deficient) based on the abnormal motion demonstrated by clinical examination tests for instability. At surgery, injuries to the intraarticular and extraarticular anatomic structures were identified and correlated to the abnormal grades of motion demonstrated by the knee motion limits examination. Tears of the anterior cruciate ligament occurred in 80 (98%) of the knees. However, the grade of abnormal motion demonstrated by the Lachman and pivot shift tests was quite variable. This variation did not correlate statistically with anterior cruciate ligament tears. Injuries to the anatomic components of the iliotibial tract were confirmed in 76 (93%) of the knees. These injuries correlated highly with variations in grades of abnormal motion detected by the following tests: lateral joint line opening at 30 degrees (r2 = 0.05); Lachman test (r2 = 0.08); pivot shift (r2 = 0.16); and anterior translation at 90 degrees of flexion (r2 = 0.34). Thus, injuries to the components of the iliotibial tract are thought to contribute to the variation in grades of abnormal motion observed in this complex subgroup of anterior tibial translation instabilities.

Ligament tension pattern in the flexed knee in combined passive anterior translation and axial rotation

Twenty-two fresh-frozen specimens were used to measure tensions generated in selected bands of the major ligaments of the flexed knee (40-90 degrees) when an axially prerotated tibia is subjected to passive anterior shear and when an anteriorly pretranslated tibia is subjected to passive axial torque. The tensions were measured using the buckle transducer attached to the anteromedial band of the anterior cruciate ligament [ACL (am)], the posterior fibers of the posterior cruciate ligament [PCL (pf)], the long fibers of the medial collateral ligament [MCL (lf)], and in the total lateral collateral ligament [LCL]. The knee specimens were subjected to the combined motions in a 6-df passive loading apparatus. The results indicated that the joint resistance to anterior translation increased markedly with internal prerotation and only marginally with external prerotation. This increase in joint resistance, however, was associated with a decrease in ACL function. It has been inferred that the posterior structures, capsular and meniscal, contribute significantly to joint resistance when the tibia is prerotated in either sense. For internal prerotation, the interference between the medial femoral condyle and the central tibial eminence was found to be an additional mechanism of resistance to anterior translation. Also, it has been found that although the ACL (am) tension increased with internal rotation in the normal case, it decreased with internal rotation in the presence of an anterior pretranslation. It is concluded that ACL response to combined joint motion cannot be ascertained by a simple summation of its responses to individual motions.