Methods to diagnose acute anterior cruciate ligament rupture: a meta-analysis of physical examinations with and without anaesthesia

Dynamic radiostereometry can objectively quantify the kinematic laxity patterns and rotation instability of the knee during a pivot-shift test

PURPOSE

The pivot-shift test is used to clinically assess knee instability in patients with anterior cruciate ligament (ACL) lesions; however, it has low interobserver reliability. Dynamic radiostereometry (dRSA) is a highly precise and noninvasive method for the objective evaluation of joint kinematics. The purpose of this study was to quantify precise knee kinematics during a pivot-shift test using dRSA imaging.

METHOD

Eight human donor legs, including hemipelvises, were evaluated. Arthroscopic intervention was performed inducing ligament lesions in the ACL, and anterolateral ligament (ALL) section was performed as a capsular incision. The pivot-shift test was recorded with dRSA on knees with intact ligaments, ACL-deficient and ACL + ALL-deficient knees.

RESULTS

A pivot-shift pattern was identifiable after ligament lesion, as a change in tibial posterior drawer velocity from 7.8 mm/s (95% CI: 3.7; 11.9) in ligament intact knees to 30.4 mm/s (95% CI 23.0; 38.8) after ACL lesion to 35.1 mm/s (95% CI 23.4; 46.7) after combined ACL-ALL lesion. The anterior-posterior drawer excursion increased from 2.8 mm (95% CI 2.1; 3.4) in ligament intact knees to 7.2 mm (95% CI 5.5; 8.9) after ACL lesion to 7.6 mm (95% CI 5.5; 9.8) after combined lesion. A statistically significant increase in tibial external rotation towards the end of the pivot-shift motion was observed when progressing from intact to ACL + ALL-deficient knees (p < 0.023).

CONCLUSION

This experimental study demonstrates the feasibility of dRSA to objectively quantify the kinematic laxity patterns of the knee during the pivot-shift test. The dynamic parameters obtained through dRSA revealed the kinematic changes from ACL to combined ACL-ALL ligament lesion.

LEVEL OF EVIDENCE

Not applicable.

Diagnostic Accuracy of Non-invasive Tests Versus Arthroscopy in Anterior Cruciate Ligament (ACL) Injuries

BACKGROUND

The knee joint assessment to detect anterior cruciate ligament (ACL) injury after trauma involves clinical examination and radiography. The gold standard method is doing arthroscopy. We did this study seeking to evaluate the effectiveness of other non-invasive diagnostic methods, including the Anterior Drawer test, Lachman test and magnetic resonance imaging (MRI) in detecting ACL tears after trauma, compared to the reference standard method (the arthroscopy).

METHODOLOGY

This descriptive cross-sectional study was conducted in the Orthopaedic Department of the Khyber Teaching Hospital, Peshawar, for six months. A total of 86 participants with knee injuries fulfilling the inclusion criteria were recruited for the study. Mechanism of injury, side of injury and body weight were recorded. The Anterior Drawer test and Lachman test for ACL injury were performed by orthopaedic surgeons with at least five years of post-fellowship experience in orthopaedic surgery. Sensitivities, specificities and accuracy of the clinical tests and MRI were calculated.

RESULTS

The statistical analysis revealed that the mean age of participants was 35.73 (SD 12.7) years, with a range from 18 to 55 years. Among the participants, 67 (77.91%) were male and 19 (22.09%) were female. The side of injury was predominantly right in 50 (58.14%) and left in 36 (41.86%) participants. Road traffic accidents (RTAs) were the leading cause of knee injury, accounting for 63.95% (55) of cases, followed by sports injuries at 23.26% (20). Regarding diagnostic accuracy, MRI showed a sensitivity of 98.57%, specificity of 87.50% and diagnostic accuracy of 96.51% in detecting ACL tears. The Lachman test demonstrated a sensitivity of 90%, specificity of 87.5% and diagnostic accuracy of 89.53% compared to arthroscopy. Similarly, the anterior Drawer test exhibited a sensitivity of 88.57%, specificity of 87.50% and diagnostic accuracy of 88.37% against the gold standard of arthroscopy. These findings underscore the effectiveness of these diagnostic modalities in identifying ACL injuries.

CONCLUSIONS

All three tests (MRI, Lachman test and anterior Drawer test) can be used for the diagnosis of anterior cruciate ligament injury with optimal results.

Diagnostic accuracy of lever sign test in acute and chronic ACL injuries

Introduction

The anterior cruciate ligament (ACL) is a commonly affected knee ligament prone to frequent injuries. Henceforth, we aimed to determine the diagnostic accuracy of lever sign test in Acute and chronic ACL injuries.

Method

At the institution's initial outpatient visit, 150 consecutive patients (92 males and 58 females) were evaluated. Total 108 patients had injury in their right leg, whereas 42 had injury in their left leg. Based on time since injury, the patients were divided into Acute and chronic groups. Clinical examinations (lachman's test and lelli's test) of all patients were confirmed with arthroscopic findings and compared between the two groups.

Results

In the acute ACL injury, the lever test had a kappa value 0.704. The accuracy and sensitivity of the Lachman, anterior drawer, pivot shift, and lever tests were calculated. We found that the lever test had the highest accuracy and sensitivity (85.48 %, 91.18 %) than the rest. In the chronic ACL injury, the kappa value for the results of the Lachman test evaluation was 0.723. The chronic ACL injuries accuracy and sensitivity values for the Lachman (86.36 %, 91.67 %), anterior drawer (76.14 %, 81.25 %), pivot shift (55.68 %, 58.49 %), and lever tests were determined.

Conclusion

The lever sign test is more accurate and reliable in the acute ACL injuries, while the Lachman test is more accurate and reliable in the chronic ACL injuries.

Lever sign test shows high diagnostic accuracy for anterior cruciate ligament injuries: A systematic review and meta-analysis of 3299 observations

PURPOSE

Injuries of the anterior cruciate ligament (ACL) are common knee injuries among active and younger patients. The Lever Sign Test (LST) is a relatively newer test, of which the accuracy is disputed in the existing literature. The aim of this study was to assess the accuracy with and without anesthesia of the Lever Sign test in the literature.

METHODS

PRISMA guidelines were followed, studies were identified using PubMed, EMBASE and Google Scholar. All studies that reported accuracy of LST performed by a clinical professional were included. Integrity of ACL was confirmed using magnetic resonance imaging or arthroscopy. Sensitivity and specificity were calculated using uni- and bivariate methods.

RESULTS

After inclusion, 3299 observations in 2516 patients were included from 23 studies. Mean age was 31.8 years and 64.2% were male. Without anesthesia, sensitivity was 79.2% (95% CI 68.7-86.9) and specificity was 92.0% (95% CI 82.2-96.6). An area under the curve (AUC) of 86.1% was found. With anesthesia, sensitivity was 86.6% (95% CI 68.0-95.2), specificity was 93.4% (95% CI 84.5-97.3) and the AUC was 91.6%.

CONCLUSION

The Lever Sign test shows very good to excellent accuracy for ACL injury, and is a useful tool for clinical practice.

Pelvic floor injury during vaginal birth is life-altering and preventable: what can we do about it?

Pelvic floor disorders after childbirth have distressing lifelong consequences for women, requiring more than 300,000 women to have surgery annually. This represents approximately 10% of the 3 million women who give birth vaginally each year. Vaginal birth is the largest modifiable risk factor for prolapse, the pelvic floor disorder most strongly associated with birth, and is an important contributor to stress incontinence. These disorders require 10 times as many operations as anal sphincter injuries. Imaging shows that injuries of the levator ani muscle, perineal body, and membrane occur in up to 19% of primiparous women. During birth, the levator muscle and birth canal tissues must stretch to more than 3 times their original length; it is this overstretching that is responsible for the muscle tear visible on imaging rather than compression or neuropathy. The injury is present in 55% of women with prolapse later in life, with an odds ratio of 7.3, compared with women with normal support. In addition, levator damage can affect other aspects of hiatal closure, such as the perineal body and membrane. These injuries are associated with an enlarged urogenital hiatus, now known as antedate prolapse, and with prolapse surgery failure. Risk factors for levator injury are multifactorial and include forceps delivery, occiput posterior birth, older maternal age, long second stage of labor, and birthweight of >4000 g. Delivery with a vacuum device is associated with reduced levator damage. Other steps that might logically reduce injuries include manual rotation from occiput posterior to occiput anterior, slow gradual delivery, perineal massage or compresses, and early induction of labor, but these require study to document protection. In addition, teaching women to avoid pushing against a contracted levator muscle would likely decrease injury risk by decreasing tension on the vulnerable muscle origin. Providing care for women who have experienced difficult deliveries can be enhanced with early recognition, physical therapy, and attention to recovery. It is only right that women be made aware of these risks during pregnancy. Educating women on the long-term pelvic floor sequelae of childbirth should be performed antenatally so that they can be empowered to make informed decisions about management decisions during labor.

The Role of Artificial Intelligence in Anterior Cruciate Ligament Injuries: Current Concepts and Future Perspectives

The remarkable progress in data aggregation and deep learning algorithms has positioned artificial intelligence (AI) and machine learning (ML) to revolutionize the field of medicine. AI is becoming more and more prevalent in the healthcare sector, and its impact on orthopedic surgery is already evident in several fields. This review aims to examine the literature that explores the comprehensive clinical relevance of AI-based tools utilized before, during, and after anterior cruciate ligament (ACL) reconstruction. The review focuses on current clinical applications and future prospects in preoperative management, encompassing risk prediction and diagnostics; intraoperative tools, specifically navigation, identifying complex anatomic landmarks during surgery; and postoperative applications in terms of postoperative care and rehabilitation. Additionally, AI tools in educational and training settings are presented. Orthopedic surgeons are showing a growing interest in AI, as evidenced by the applications discussed in this review, particularly those related to ACL injury. The exponential increase in studies on AI tools applicable to the management of ACL tears promises a significant future impact in its clinical application, with growing attention from orthopedic surgeons.

Lateral Extra-Articular Tenodesis with Indirect Femoral Fixation Using an Anterior Cruciate Ligament Reconstruction Suspensory Device

BACKGROUND

The lateral extra-articular tenodesis (LET) procedure associated with anterior cruciate ligament (ACL) reconstruction can be considered in selected patients to diminish the risk of persistent rotatory instability and achieve a protective effect on the graft. Several techniques have been described in the literature to treat rotatory instability. Usually, a strip of the iliotibial band (ITB) is harvested from its middle while leaving the distal insertion, then passed underneath the lateral collateral ligament and fixed on the lateral aspect of the distal femur with various fixation methods such as staples, screws, anchors or extracortical suspensory devices. Despite their effectiveness, these fixation methods may be associated with complications such as lateral pain, over-constraint and tunnel convergence.

METHODS

This study presents a detailed surgical description of a new technique to perform an LET during ACL reconstruction with any type of graft fixing the ITB strip with the sutures of the ACL femoral button, comparing its pros and cons in relation to similar techniques found in the literature.

CONCLUSIONS

This technique represents a reproducible, easy to learn and inexpensive solution to perform a lateral extra-articular tenodesis associated with an ACL reconstruction using the high-resistance sutures of the femoral button.

Subregional analysis of joint stiffness facilitates insight into ligamentous laxity after ACL injury

Purpose: Increased incidence of anterior cruciate ligament injuries has amplified the need for quantitative research in clinical and academic settings. We used a novel digital arthrometer to measure knee laxity in healthy people and patients with anterior cruciate ligament injuries. Changes in stiffness were also assessed to develop new indicators for detecting anterior cruciate ligament injury. The purpose of this study was to use arthrometer to measure the quantitative indicator of knee laxity, bringing clinicians a new perspective on how to identify injury to the ACL. Methods: In this cross-sectional study, anterior tibial displacement under continuous loading was measured using a novel digital arthrometer in 30 patients with unilateral anterior cruciate ligament injury and 30 healthy controls. Load-displacement curves were plotted, using real-time load and displacement changes. Stiffness was defined by the slope of the applied load to tibial displacement. Anterior tibial displacement and instantaneous stiffness values under different loads were compared. The restricting contribution of the anterior cruciate ligament transformed the displacement-stiffness curve from a sharp decrease to a stable increase, resulting in a minimum stiffness value. Using the minimum stiffness as the turning point, the load-displacement curve was divided into regions 1 and 2. The two regions' stiffness changes were compared. Based on the findings, receiver operating characteristic curves were plotted and the area under the curve was calculated to estimate the diagnostic accuracy. Results: Anterior tibial displacement was significantly greater in the anterior cruciate ligament injury group than in the controls under each 10-N increase load (p < 0.05). In the anterior cruciate ligament injury group, instantaneous stiffness was significantly lower on the injured side than on the healthy side (p < 0.05). In the two regions of the load-displacement curve, stiffness was significantly lower in the anterior cruciate ligament injury group than in the control group (all, p < 0.05). Receiver operating characteristic curves were plotted, using changes in stiffness under the two regions in both groups. Stiffness in region 2 had the largest area under the curve (0.94; 95% CI, 0.88-0.99). Using the cut-off value of 9.62 N/mm to detect ACL injury, the sensitivity and specificity were 93% and 82%, respectively. Conclusion: Our investigation of ligament stiffness provides novel insights into the properties of knee laxity. Stiffness in the later stages of increased loading <9.62 N/mm could be a valid indicator for identifying knee laxity.

[Reliability and validity of the Lever Sign Test in suspected ligament and/or meniscus injuries of the knee: a comparison between an orthopaedist and a physical therapist]

INTRODUCTION

The purpose of this study was to investigate the intertester reliability and validity of the Lever Sign Test. Intertester reliability has received little attention in previous studies. In order to make comparisons with other studies, the intertester reliability and validity of the Lachman and Anterior Drawer Tests were also calculated.

PATIENTS/MATERIAL AND METHODS

Patients between 18 and 50 years of age with suspected ligament and/or meniscus injuries were included. Exclusion criteria were suspected malignant, systemic, or central neurologic disease, acute cartilage injury, suspected fracture, or knowledge of the participant's knee findings. Testing was randomized and blinded by an experienced orthopaedic surgeon and a physical therapist. Cohen's kappa was calculated for intertester reliability. Sensitivity and specificity, positive and negative predictive value, and positive and negative likelihood ratio were calculated. MRI findings were used as the gold standard.

RESULTS

Thirty-six patients were enrolled in the study, 27 male (75%) and 9 female (25%). The prevalence of anterior cruciate ligament lesions was 44.4%. Cohen's kappa (κ) was κ=0.6 (CI 95% [0.29, 0.91]) for the Lever Sign Test, κ=0.64 (CI 95% [0.35, 0.93]) for the Lachman test, and κ=0.63 (CI 95% [0.3, 0.95]) for the Anterior Drawer Test. The sensitivity of the Lever Sign Test was 0.53 and 0.40 for the orthopaedic surgeon and physical therapist, respectively, specificity was 0.89 and 0.79, the positive predictive value was 0.80 and 0.60, the negative predictive value was 0.70 and 0.62, the positive likelihood ratio was 4.80 and 1.90, respectively, and the negative likelihood ratio was 0.76 and 0.53.

CONCLUSION

The estimated intertester reliability of the Lever Sign Test was good. The Lever Sign Test is suitable as a complement to the Lachman Test, which is considered the most valid test in the literature. The weaknesses and ambiguities of the operating mechanism of the Lever Sign Test should not be ignored and should be further explored.

Investigating the effect of autograft diameter for quadriceps and patellar tendons use in anterior cruciate ligament reconstruction: a biomechanical analysis using a simulated Lachman test

Introduction

Current clinical practice suggests using patellar and quadriceps tendon autografts with a 10 mm diameter for ACL reconstruction. This can be problematic for patients with smaller body frames. Our study objective was to determine the minimum diameter required for these grafts. We hypothesize that given the strength and stiffness of these respective tissues, they can withstand a significant decrease in diameter before demonstrating mechanical strength unviable for recreating the knee's stability.

Methods

We created a finite element model of the human knee with boundary conditions characteristic of the Lachman test, a passive accessory movement test of the knee performed to identify the integrity of the anterior cruciate ligament (ACL). The Mechanical properties of the model's grafts were directly obtained from cadaveric testing and the literature. Our model estimated the forces required to displace the tibia from the femur with varying graft diameters.

Results

The 7 mm diameter patellar and quadriceps tendon grafts could withstand 55-60 N of force before induced tibial displacement. However, grafts of 5.34- and 3.76-mm diameters could only withstand upwards of 47 N and 40 N, respectively. Additionally, at a graft diameter of 3.76 mm, the patellar tendon experienced 234% greater stiffness than the quadriceps tendon, with similar excesses of stiffness demonstrated for the 5.34- and 7-mm diameter grafts.

Conclusions

The patellar tendon provided a stronger graft for knee reconstruction at all diameter sizes. Additionally, it experienced higher maximum stress, meaning it dissociates force better across the graft than the quadriceps tendon. Significantly lower amounts of force were required to displace the tibia for the patellar and quadriceps tendon grafts at 3.76- and 5.34-mm graft diameters. Based on this point, we conclude that grafts below the 7 mm diameter have a higher chance of failure regardless of graft selection.

Evaluation of the accuracy and intra- and interobserver reliability of three manual laxity tests for canine cranial cruciate ligament rupture-An ex vivo kinetic and kinematic study

OBJECTIVES

To investigate the accuracy and intra- and interobserver reliability of the cranial drawer test (CD), tibial compression test (TCT), and the new tibial pivot compression test (TPCT) in an experimental setting resembling acute cranial cruciate ligament rupture (CCLR) and to elucidate the ability to subjectively estimate cranial tibial translation (CTT) during testing.

STUDY DESIGN

Experimental ex vivo study.

SAMPLE POPULATION

Ten cadaveric hindlimbs of large dogs.

METHODS

Kinetic and 3D-kinematic data was collected while three observers performed the tests on each specimen with intact (INTACT) and transected cranial cruciate ligament (CCLD) and compared using three-way repeated-measures ANOVA. Subjectively estimated CTT (SCTT), obtained during a separate round of testing, was compared to kinematic data by Pearson correlation.

RESULTS

CTT was significantly higher for CCLD than for INTACT for all tests, resulting in 100% sensitivity and specificity. TPCT induced the highest CTT and internal rotation. Intra- and interobserver agreement of translation was excellent. For rotation and kinetics, agreement was more variable. SCTT strongly correlated with the objectively measured values.

CONCLUSION

The CD, TCT and the new TPCT were all accurate and reliable. The high translations and rotations during TPCT are promising, encouraging further development of this test. SCTT was reliable in our experimental setting.

CLINICAL SIGNIFICANCE

Veterinary manual laxity tests are accurate and reliable in acute CCLR. The TPCT might have potential for the assessment of subtle and rotational canine stifle instabilities. The high reliability of SCTT implies that grading schemes for stifle laxity, similar to human medicine, could be developed.

Anatomical and Biomechanical Characteristics of the Anterolateral Ligament: A Descriptive Korean Cadaveric Study Using a Triaxial Accelerometer

Background and Objectives: The anterolateral ligament (ALL) could be the potential anatomical structure responsible for rotational instability after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to investigate the anatomical and biomechanical characteristics of the ALL in Korean cadaveric knee joints. Materials and Methods: Twenty fresh-frozen cadaveric knees were dissected and tested. Femoral and tibial footprints of the ALL were recorded. Pivot shift and Lachman tests were measured with KiRA. Results: The prevalence of ALL was 100%. The average distance of the tibial footprint to the tip of the fibular head was 19.85 ± 3.41 mm; from the tibial footprint to Gerdy's tubercle (GT) was 18.3 ± 4.19 mm; from the femoral footprint to the lateral femoral epicondyle was 10.25 ± 2.97 mm. ALL's footprint distance was the longest at 30° of flexion (47.83 ± 8.05 mm, p < 0.01) in a knee with intact ALL-ACL and neutral rotation. During internal rotation, the footprint distance was the longest at 30° of flexion (50.05 ± 8.88 mm, p < 0.01). Internal rotation produced a significant increase at all three angles after ACL-ALL were transected (p = 0.022), where the footprint distance was the longest at 30° of flexion (52.05 ± 7.60 mm). No significant difference was observed in KiRA measurements between intact ALL-ACL and ALL-transected knees for pivot shift and Lachman tests. However, ACL-ALL-transected knees showed significant differences compared to the intact ALL-ACL and ALL-transected knees (p < 0.01). Conclusions: The ALL was identified as a distinct ligament structure with a 100% prevalence in this cadaveric study. The ALL plays a protective role in internal rotational stability. An isolated ALL transection did not significantly affect the ALL footprint distances or functional stability tests. Therefore, the ALL is thought to act as a secondary supportive stabilizer for rotational stability of the knee joint in conjunction with the ACL.

Radiomics and Deep Learning for Disease Detection in Musculoskeletal Radiology: An Overview of Novel MRI- and CT-Based Approaches

ABSTRACT

Radiomics and machine learning-based methods offer exciting opportunities for improving diagnostic performance and efficiency in musculoskeletal radiology for various tasks, including acute injuries, chronic conditions, spinal abnormalities, and neoplasms. While early radiomics-based methods were often limited to a smaller number of higher-order image feature extractions, applying machine learning-based analytic models, multifactorial correlations, and classifiers now permits big data processing and testing thousands of features to identify relevant markers. A growing number of novel deep learning-based methods describe magnetic resonance imaging- and computed tomography-based algorithms for diagnosing anterior cruciate ligament tears, meniscus tears, articular cartilage defects, rotator cuff tears, fractures, metastatic skeletal disease, and soft tissue tumors. Initial radiomics and deep learning techniques have focused on binary detection tasks, such as determining the presence or absence of a single abnormality and differentiation of benign versus malignant. Newer-generation algorithms aim to include practically relevant multiclass characterization of detected abnormalities, such as typing and malignancy grading of neoplasms. So-called delta-radiomics assess tumor features before and after treatment, with temporal changes of radiomics features serving as surrogate markers for tumor responses to treatment. New approaches also predict treatment success rates, surgical resection completeness, and recurrence risk. Practice-relevant goals for the next generation of algorithms include diagnostic whole-organ and advanced classification capabilities. Important research objectives to fill current knowledge gaps include well-designed research studies to understand how diagnostic performances and suggested efficiency gains of isolated research settings translate into routine daily clinical practice. This article summarizes current radiomics- and machine learning-based magnetic resonance imaging and computed tomography approaches for musculoskeletal disease detection and offers a perspective on future goals and objectives.

Internal Brace Ligament Augmentation versus Anatomical Repair with Hamstrings of the ACL – A Clinical Data Comparison Study

AIM: Investigation into the clinical results of internal brace ligament augmentation technique compared to the simple anatomical repair of the anterior cruciate ligament (ACL). METHODS: From May 2016 to November 2019, 128 patients underwent an operation using the internal brace technique. During the same time, 104 patients were operated on using the simple anatomical ACL repair. The mean age was 22.5-year-old for the first group and 26.8-year- old for the second one. The minimum follow-up was 24 months. All the patients performed an X-ray and magnetic resonance imaging. Two hypotheses were raised to assess the superiority of the internal brace technique versus the anatomical one in the early post-operative phase and the rehabilitation one. RESULTS: The mean operation time was 71 (65–75) min for the internal brace (IB) and 62 (55–65) for the anatomical. We had two post-operative infected knees in the first group (IB) and no infection in the second one. The clinical stability test results were much better in the IB group using the KT 1000. The rehabilitation phase showed a superior IB technique. The return to sport-time of the sportsmen was 6 months for the first group and 7–8 months for the anatomical. All the IB-operated patients found physiotherapy significantly easier than the anatomical ones. CONCLUSIONS: IB-technique performs better clinical outcomes than the anatomical repair. The presence of a foreign body (Ultrabraid) inside the knee may be a risk factor contributing toward the elevated infection rate. The IB technique costs are significantly more expensive compared to the anatomical but the low physiotherapy costs compensate for the final result.

A high level of knee laxity after anterior cruciate ligament reconstruction results in high revision rates

PURPOSE

The literature indicates a lack of consensus on the correlation between knee laxity after anterior cruciate ligament reconstruction (ACLR) and subjective clinical outcomes and the need for revision surgery. Therefore, using high-volume registry data, this study aimed to describe the relationship between objective knee laxity after ACLR and subjective symptom and functional assessments and the need for revision surgery. The hypothesis was that greater postoperative knee laxity would correlate with inferior patient-reported outcomes and a higher risk for revision surgery.

METHODS

In this study, 17,114 patients in the Danish knee ligament reconstruction registry were placed into three groups on the basis of objective side-to-side differences in sagittal laxity one year after surgery: group A (≤ 2 mm), Group B (3-5 mm) and Group C (> 5 mm). The main outcome measure was revision rate within 2 years of primary surgery, further outcome measures were the knee injury and osteoarthritis outcome score (KOOS) as well as Tegner activity score.

RESULTS

The study found the risk for revision surgery was more than five times higher for Group C [hazard ratio (HR) = 5.51] than for Group A. The KOOS knee-related Quality of Life (QoL) sub-score exhibited lower values when comparing Groups B or C to Group A. In addition, the KOOS Function in Sport and Recreation (Sport/Rec) sub-score yielded lower values for groups B and C in comparison with Group A.

CONCLUSION

These results indicate that increased post-operative sagittal laxity is correlated with an increased risk for revision surgery and might correlate with poorer knee-related QoL, as well as a decreased function in sports. The clinical relevance of the present study is that high knee laxity at 1-year follow-up is a predictor of the risk of revision surgery.

LEVEL OF EVIDENCE

III.

Anterior Tibial Subluxation of Lateral Compartment Is Associated With High-Grade Rotatory Instability for Acute But Not Chronic Anterior Cruciate Ligament Injuries: An Magnetic Resonance Imaging Case-Control Study

PURPOSE

To investigate whether anterior tibial subluxation obtained from magnetic resonance imaging (MRI) could be a predictor of high-grade rotatory instability for anterior cruciate ligament (ACL) injuries, including acute and chronic cases.

METHODS

From September 2016 to August 2018, we retrospectively investigated 163 patients with ACL injuries who subsequently underwent primary ACL reconstruction. Among them, 30 patients with high-grade rotatory instability (grade II/III pivot shift) were included in the high-grade group, and their age and sex were matched 1:2 to low-grade cases (<grade II pivot shift). On preoperative MRI, we measured anterior tibial subluxation, posterior tibial slope, as well as the time from injury to surgery. Meniscal lesions were documented from arthroscopy. Multivariable logistic regression was used to determine predictors of high-grade rotatory instability. Furthermore, subgroup comparisons between 2 groups were divided into acute (≤3 months) and chronic (>3 months) phases.

RESULTS

The high-grade group had a larger anterior tibial subluxation of lateral compartment (8.1 mm vs 5.9 mm; P =.004) than the low-grade group, whereas no significant difference was found in anterior tibial subluxation of medial compartment (P > .05). Moreover, high-grade anterior tibial subluxation of lateral compartment (≥6 mm) was found to be an independent predictor (odds ratio, 12.992; P = .011) associated with concomitant meniscal tears after ACL injuries. Anterior tibial subluxation of lateral compartment demonstrated statistical significance between the two groups when comparing subgroups within 3 months but not beyond 3 months.

CONCLUSION

In ACL-injured patients, high-grade anterior tibial subluxation of lateral compartment (≥6 mm) could be a unique predictor of high-grade knee rotatory instability for acute but not chronic injuries. Prolonged time from injury to surgery and lateral meniscus tears were risk factors for high-grade rotatory laxity in chronic patients.

LEVEL OF EVIDENCE

Level III, retrospective prognostic trial.

Higher sensitivity with the lever sign test for diagnosis of anterior cruciate ligament rupture in the emergency department

INTRODUCTION

The objective of this study was to assess the diagnostic value of the "lever sign test" to diagnose ACL rupture and to compare this test to the two most commonly used, the Lachman and anterior drawer test.

METHOD

This prospective study was performed in the ED of the Cliniques Universitaires Saint-Luc (Brussels, Belgium) from March 2017 to May 2019. 52 patients were included undergoing knee trauma, within 8 days, with an initial radiograph excluding a fracture (except Segond fracture or tibial spine fracture). On clinical investigation, patients showed a positive lever sign test and/or a positive Lachman test and/or a positive anterior drawer test. Exclusion criteria were a complete rupture of the knee extensor mechanism and patellar dislocation. All the physicians involved in this study were residents in training. An MRI was performed within 3 weeks for all included patients after the clinical examination. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were investigated for all three tests with MRI used as our reference standard.

RESULTS

Forty out of 52 patients suffered an ACL rupture (77%) and 12 did not (23%). The sensitivity, specificity, PPV and NPV of the lever sign test were respectively 92.5%, 25% 82% and 50%. Those of the Lachman test were 54%, 54.5%, 81% and 25%, and those of the anterior drawer test were 56%, 82%, 90.5% and 37.5%. Twelve out of 40 ACL ruptures (30%) were diagnosed exclusively with a positive lever sign test.

CONCLUSION

When investigating acute ACL ruptures (< 8 days) in the ED, the lever sign test offers a sensitivity of 92.5%, far superior to that of other well-known clinical tests. The lever sign test is relatively pain-free, easy to perform and its visual interpretation requires less experience. Positive lever sign test at the ED should lead to an MRI to combine high clinical sensitivity with high MRI specificity.

Evaluating the diagnostic pathway for acute ACL injuries in trauma centres: a systematic review

Objective

This review sought to evaluate the literature on the initial assessment and diagnostic pathway for patients with a suspected Anterior Cruciate Ligament (ACL) tear.

Methods

MEDLINE, EMBASE, and CINAHL were systematically searched for eligible studies, PRISMA guidelines were followed. Studies were included if they used at least one assessment method to assess for ACL injury and participants were assessed at an acute trauma centre within 6-weeks of injury. Article quality was evaluated using the QUADAS-2 checklist.

Results

A total of 353 studies were assessed for eligibility, 347 were excluded for the following reasons: injuries were not assessed in an acute trauma setting, injuries were not acute, participants had previous ACL injuries or chronic joint deformities affecting the knee, participants were under 18, or participants included animals or cadavers. A total of six studies were included in the review. Common assessment methods included: laxity tests, joint effusion, inability to continue activity, and a history of a ‘pop’ and ‘giving way’ at the time of injury. Diagnostic accuracy varied greatly between the assessment method and the assessing clinician. Gold standard diagnostics were MRI and arthroscopy. A weighted meta-mean calculated the time to reach diagnosis to be 68.60 days [CI 23.94, 113.24]. The mean number of appointments to reach diagnosis varied from 2–5. Delay to surgery or surgical consultation ranged from 61 to 328 days.

Conclusion

Clinicians in the Emergency Department are not proficient in performing the assessment methods that are used for diagnosis in acute ACL injury. Reliance on specialist assessments or radiological methods inevitably increases the time to reach a diagnosis, which has repercussions on management options. There is an ever-growing demand to improve diagnostic accuracy and efficiency; further exploration into quantitative measures of instability would aid the assessment of peripheral joint assessment.

Hamstring tendon autografts and allografts show comparable clinical outcomes and knee stability after anterior cruciate ligament reconstruction in patients over fifty years old with no signs of osteoarthritis progression

Purpose

The aim of this study is to compare the functional outcomes and osteoarthritis (OA) progression after anterior cruciate ligament (ACL) reconstruction with either hamstring autografts or allografts in people over 50.

Methods

The clinical records of two consecutive cohorts of 61 cases in total over 50 years of age, undergoing ACL reconstruction, were included. The first cohort consisted of 29 allografts; the second cohort consisted of 32 autologous hamstring tendon grafts. The cases were evaluated pre- (T0) and post-operatively at six months (T1), 12 months (T2) and 24 months (T3). Clinical examination included the Lachman test, pivot shift test and objective (Objective IKDC [The International Knee Documentation Committee] score) and subjective clinical scores (Subjective IKDC score, Lysholm score and Tegner activity score). The degree of OA was evaluated using the Kellgren-Lawrence system at the time of the final follow-up, compared to the pre-operative condition.

Results

No pre-operative difference was found between the two groups (p > 0.05). No statistical difference was noted between the two groups at each follow-up (p > 0.05). At the final follow-up, both the groups significantly improved statistically in all the clinical and functional scores (p < 0.05). In both groups, one graft re-rupture was noted. No progression of OA was noted in both groups at final follow-up (p > 0.05).

Conclusion

The graft choice does not influence the outcomes two years after ACL reconstruction in people over 50; thus, both treatments help in regaining knee stability with no signs of OA progression.

Registration

Researchregistry7539–www.researchregistry.com.

Evaluation of anterior cruciate ligament surgical reconstruction through finite element analysis

Anterior cruciate ligament (ACL) tear is one of the most common knee injuries. The ACL reconstruction surgery aims to restore healthy knee function by replacing the injured ligament with a graft. Proper selection of the optimal surgery parameters is a complex task. To this end, we developed an automated modeling framework that accepts subject-specific geometries and produces finite element knee models incorporating different surgical techniques. Initially, we developed a reference model of the intact knee, validated with data provided by the Open Knee(s) project. This helped us evaluate the effectiveness of estimating ligament stiffness directly from MRI. Next, we performed a plethora of “what-if” simulations, comparing responses with the reference model. We found that (a) increasing graft pretension and radius reduces relative knee displacement, (b) the correlation of graft radius and tension should not be neglected, (c) graft fixation angle of 20\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{\circ }$$\end{document}∘ can reduce knee laxity, and (d) single-versus double-bundle techniques demonstrate comparable performance in restraining knee translation. In most cases, these findings confirm reported values from comparative clinical studies. The numerical models are made publicly available, allowing for experimental reuse and lowering the barriers for meta-studies. The modeling approach proposed here can complement orthopedic surgeons in their decision-making.

Grade III pivot shift as an early sign of knee decompensation in chronic ACL-injured knees with bimeniscal tears

PURPOSE

To analyse possible associations between the preoperative pivot shift (PS) test and both patient and injury characteristics in anterior cruciate ligament (ACL)-injured knees, considering previously neglected meniscal injuries such as ramp and root tears. The hypothesis was that a preoperative grade III PS was associated with the amount of intra-articular soft-tissue damage and chronicity of the injury.

METHODS

The cohort involved 376 patients who underwent primary ACL reconstruction (239 males/137 females; median age 26). Patients were examined under anesthesia before surgery, using the PS test. During arthroscopy, intra-articular soft-tissue damage of the injured knee was classified as: (1) partial ACL tear; (2) complete isolated ACL tear; (3) complete ACL tear with one meniscus tear; and (4) complete ACL and bimeniscal tears. Chi-square and Mann-Whitney U tests were used to evaluate whether sex, age, body mass index, sport at injury, mechanism of injury, time from injury and intra-articular damage (structural damage of ACL and menisci) were associated with a grade III PS. Intra-articular damage was further analyzed for two sub-cohorts: acute (time from injury ≤ 6 months) and chronic injuries (> 6 months).

RESULTS

A grade III PS test was observed in 26% of patients. A significant association with PS grading was shown for age, time from injury and intra-articular soft-tissue damage (p < 0.05). Further analyses showed that grade III PS was associated with intra-articular damage in chronic injuries only (p < 0.01). In complete ACL and bimeniscal tears, grade III PS was more frequent in chronic (53%) than in acute knee injuries (26%; p < 0.01). Patients with chronic complete ACL and bimeniscal tears had a grade III PS 3.3 [1.3-8.2] times more often than patients in the acute sub-cohort.

CONCLUSION

In ACL-injured patients, a preoperative grade III PS was mainly associated with a higher amount of intra-articular soft-tissue damage and chronicity of the injury. Patients with complete chronic ACL injuries and bimeniscal tears were more likely to have a preoperative grade III PS than their acute counterparts. This suggests that grade III PS may be an early sign of knee decompensation of dynamic rotational knee laxity in chronic ACL-injured knees with bimeniscal lesions.

LEVEL OF EVIDENCE

Level III.

High incidence of superficial and deep medial collateral ligament injuries in 'isolated' anterior cruciate ligament ruptures: a long overlooked injury

PURPOSE

In anterior cruciate ligament (ACL) injuries, concomitant damage to peripheral soft tissues is associated with increased rotatory instability of the knee. The purpose of this study was to investigate the incidence and patterns of medial collateral ligament complex injuries in patients with clinically 'isolated' ACL ruptures.

METHODS

Patients who underwent ACL reconstruction for complete 'presumed isolated' ACL rupture between 2015 and 2019 were retrospectively included in this study. Patient's characteristics and intraoperative findings were retrieved from clinical and surgical documentation. Preoperative MRIs were evaluated and the grade and location of injuries to the superficial MCL (sMCL), dMCL and the posterior oblique ligament (POL) recorded. All patients were clinically assessed under anaesthesia with standard ligament laxity tests.

RESULTS

Hundred patients with a mean age of 22.3 ± 4.9 years were included. The incidence of concomitant MCL complex injuries was 67%. sMCL injuries occurred in 62%, dMCL in 31% and POL in 11% with various injury patterns. A dMCL injury was significantly associated with MRI grade II sMCL injuries, medial meniscus 'ramp' lesions seen at surgery and bone oedema at the medial femoral condyle (MFC) adjacent to the dMCL attachment site (p < 0.01). Logistic regression analysis identified younger age (OR 1.2, p < 0.05), simultaneous sMCL injury (OR 6.75, p < 0.01) and the presence of bone oedema at the MFC adjacent to the dMCL attachment site (OR 5.54, p < 0.01) as predictive factors for a dMCL injury.

CONCLUSION

The incidence of combined ACL and medial ligament complex injuries is high. Lesions of the dMCL were associated with ramp lesions, MFC bone oedema close to the dMCL attachment, and sMCL injury. Missed AMRI is a risk factor for ACL graft failure from overload and, hence, oedema in the MCL (especially dMCL) demands careful assessment for AMRI, even in the knee lacking excess valgus laxity. This study provides information about specific MCL injury patterns including the dMCL in ACL ruptures and will allow surgeons to initiate individualised treatment.

LEVEL OF EVIDENCE

III.

Artificial intelligence for MRI diagnosis of joints: a scoping review of the current state-of-the-art of deep learning-based approaches

Deep learning-based MRI diagnosis of internal joint derangement is an emerging field of artificial intelligence, which offers many exciting possibilities for musculoskeletal radiology. A variety of investigational deep learning algorithms have been developed to detect anterior cruciate ligament tears, meniscus tears, and rotator cuff disorders. Additional deep learning-based MRI algorithms have been investigated to detect Achilles tendon tears, recurrence prediction of musculoskeletal neoplasms, and complex segmentation of nerves, bones, and muscles. Proof-of-concept studies suggest that deep learning algorithms may achieve similar diagnostic performances when compared to human readers in meta-analyses; however, musculoskeletal radiologists outperformed most deep learning algorithms in studies including a direct comparison. Earlier investigations and developments of deep learning algorithms focused on the binary classification of the presence or absence of an abnormality, whereas more advanced deep learning algorithms start to include features for characterization and severity grading. While many studies have focused on comparing deep learning algorithms against human readers, there is a paucity of data on the performance differences of radiologists interpreting musculoskeletal MRI studies without and with artificial intelligence support. Similarly, studies demonstrating the generalizability and clinical applicability of deep learning algorithms using realistic clinical settings with workflow-integrated deep learning algorithms are sparse. Contingent upon future studies showing the clinical utility of deep learning algorithms, artificial intelligence may eventually translate into clinical practice to assist detection and characterization of various conditions on musculoskeletal MRI exams.

The diagnostic accuracy of clinical tests for anterior cruciate ligament tears are comparable but the Lachman test has been previously overestimated: a systematic review and meta-analysis

PURPOSE

The diagnostic accuracy of clinical tests for anterior cruciate ligament injury has been reported in previous systematic reviews. Numerous studies in these reviews include subjects with additional knee ligament injury, which could affect the sensitivity of the tests. Meta-analyses have also been performed using methods that do not account for the non-independence of sensitivity and specificity, potentially overestimating diagnostic accuracy. The aim of this study was to report the diagnostic accuracy of clinical tests for anterior cruciate ligament tears (partial and complete) without concomitant knee ligament injury.

METHODS

A systematic review with meta-analysis was performed according to the PRISMA guidelines. Meta-analyses included studies reporting the specificity and/or sensitivity of tests with or without concomitant meniscal injury. Where possible, pooled diagnostic estimates were calculated with bivariate random-effects modelling to determine the most accurate effect sizes. Diagnostic accuracy values are presented for the anterior drawer, Lachman, Lever sign and pivot shift tests overall and in acute or post-acute presentations.

RESULTS

Pooled estimates using a bivariate model for overall sensitivity and specificity respectively were as follows: anterior drawer test 83% [95% CI, 77-88] and 85% [95% CI, 64-95]; Lachman test 81% [95% CI, 73-87] and 85% [95% CI, 73-92]; pivot shift test 55% [95% CI, 47-62] and 94% [95% CI, 88-97]; Lever sign test 83% [95% CI, 68-92] and 91% [95% CI, 83-95]. For specific presentations, the sensitivity and specificity of the Lachman test, respectively, were: complete tears 68% [95% CI, 54-79] and 79% [95% CI, 51-93]; post-acute injuries 70% [95% CI, 57-80] and 77% [95% CI, 53-91].

CONCLUSIONS

The pivot shift and Lever sign were the best tests overall for ruling in or ruling out an anterior cruciate ligament tear, respectively. The diagnostic accuracy of the Lachman test, particularly in post-acute presentations and for complete tears, is lower than previously reported. Further research is required to establish more accurate estimates for the Lachman test in acute presentations and partial ligament tears using bivariate analysis.

LEVEL OF EVIDENCE

III.

Anterior Cruciate Ligament Injury: Conservative Versus Surgical Treatment

The most frequent type of ligament injury is an anterior cruciate ligament (ACL). The mechanisms of an ACL injury are classified as direct contact, indirect contact, and non-contact. Physical examination for the assessment of the ACL is commonly used in routine care in the evaluation of the knee and is part of the diagnostic process. Due to the high degree of variability in their presentation and outcomes, treatment must be tailored according to factors such as patient demographics, the severity of the damage, and long-term improvement profile. When it comes to ACL injuries, low-quality data have been produced that reveals no difference in patient-reported knee function results between surgical ACL restoration and conservative therapy. However, these results must be evaluated in the perspective of the fact that many individuals with an ACL rupture remained symptomatic after rehabilitation and eventually underwent ACL reconstruction surgery. This article has reviewed the risk factors and the mechanisms that commonly lead to ACL injuries. This article has also discussed the clinical significance of conservative and surgical management and has highlighted the implications of both approaches.

Anatomic all-epiphyseal ACL reconstruction with "inside-out" femoral tunnel placement in immature patients yields high return to sport rates and functional outcome scores a minimum of 24 months after reconstruction

PURPOSE

To understand if anatomic physeal-sparing ACL reconstruction in the immature host preserves range of motion, permits a return to sports, and avoids limb length discrepancy and accelerated intra-articular degeneration with a cross-sectional radiographic, physical examination and patient-reported outcomes analysis.

METHODS

A cross-sectional recall study included 38 patients aged 7-15 who underwent all-epiphyseal ACL reconstruction with hamstring allograft performed by a single surgeon at a large academic medical center. All-epiphyseal reconstructions were performed using a modified Anderson physeal-sparing technique, with the femoral tunnel placed using an "inside-out" technique. Assessments consisted of a physical exam, long leg cassette radiographs, KT-1000 measurements, subjective patient metrics, and magnetic resonance imaging.

RESULTS

Thirty-eight (56.7%) of 66 eligible patients returned for in-person clinical and radiographic exams. Patients were 11.4 ± 1.8 years at the time of surgery. Five patients were females (13.2%). Mean follow-up was 5.5 ± 2.4 years. ACL re-injuries occurred in four patients (10.5%), all of whom underwent revision reconstructions. Thirty-three of the remaining 34 (97.1%) patients returned to sports following their reconstruction, and 24 (70.6%) returned to their baseline level of competition. Mean limb length discrepancy (LLD) was 0.2 ± 1.4 cm. Nine patients had an LLD of > 1 cm (26.5%), which occurred at an equivalent age as those with < 1 cm LLD (10.8 ± 2.0 vs. 11.7 ± 1.7, n.s.). Pre-operative Marx scores (13.1 ± 3.5) were not significantly different from post-operative values (12.3 ± 5.1, n.s.). Patients who required ACL revisions had significantly lower Marx scores than those with intact primary grafts (8.3 ± 7.1 vs. 13.4 ± 4.5, p = 0.047). Cohort mean International Knee Documentation Committee (IKDC) score was 89.7 ± 12.7.

CONCLUSION

Anatomic all-epiphyseal anatomic ACL reconstruction appears to be useful in patients with significant projected remaining growth, with good return-to-sport outcomes and minimal risk of clinically significant physeal complications. However, given the limited patient recall possible in the present study, further large sample size, high-quality works are necessary to validate our findings.

LEVEL OF EVIDENCE

Level IV.

Anterior cruciate ligament intactness in osteoarthritic patients indicated for total knee arthroplasty: a systematic literature review and meta-analysis

Bi-cruciate retaining total knee arthroplasty (BCR TKA) is thought to result in more natural knee kinematics compared to conventional TKA designs. This may lead to a reduction in dissatisfied patients after TKA. An intact anterior cruciate ligament (ACL) is a prerequisite for implantation of a BCR TKA but the frequency of an intact ACL in patients indicated for TKA is not well known. The objective of this systematic literature review was to determine the presence of an intact ACL in patients undergoing TKA by intraoperative macroscopic or MRI assessment. A systematic literature review was conducted using PubMed™ and EMBASE™ in June 2020. The ACL of patients with knee osteoarthritis (OA) undergoing TKA was classified as present (including intact and degenerated) vs. absent, and as intact vs. not fully intact. Proportional meta-analyses were performed. 2840 articles were identified and screened. 135 full texts were analyzed and 18 studies met the inclusion criteria for subsequent qualitative and quantitative meta-analysis. Analysis of the status of the ACL when assessed intraoperatively during TKA showed that the ligament was present in 79.4% of patients (CI: 73.5-84.3%), from 14 studies with 2067 cases studied. The ACL was determined to be intact in 55.0% of patients (CI: 45.3-64.4%), from 14 studies with 1916 cases. Preoperative ACL assessment using MRI (2 studies) revealed it was present in 82.9% of 193 cases (CI: 76.9-87.6%), and intact in 56.8% of 176 cases (CI: 8.2-94.7%). This systematic literature review shows that the ACL is macroscopically intact in more than half of patients with knee OA undergoing TKA, based on intraoperative assessment of the ligament. The results suggest BCR TKA may be considered as an alternative to traditional TKA in a large number of TKA patients. More high-quality studies are needed to better understand the functional status of the ACL in TKA patients.Level of evidence III.

Association Between Psychological Readiness and Knee Laxity and Their Predictive Value for Return to Sport in Patients With Anterior Cruciate Ligament Reconstruction

BACKGROUND

Deciding when patients are ready to return to sport (RTS) after an anterior cruciate ligament (ACL) reconstruction (ACLR) is challenging. The understanding of which factors affect readiness and how they may be related is limited. Therefore, despite widespread use of RTS testing, there is a lack of knowledge about which tests are informative on the ability to resume sports.

PURPOSE

To examine whether there is an association between knee laxity and psychological readiness to RTS after ACLR and to evaluate the predictive value of these measures on sports resumption.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Patients aged ≥16 years engaged in physical activity/sports before injury were recruited at routine clinical assessment 9-12 months after ACLR. Exclusion criteria were concomitant ligament surgery at ACLR and/or previous ACL injury in the contralateral knee. At baseline, a project-specific activity questionnaire and the ACL-Return to Sport After Injury (ACL-RSI) scale were completed. Knee laxity was assessed by use of the Lachman test, KT-1000 arthrometer, and pivot-shift test. Two years after surgery, knee reinjuries and RTS status (the project-specific questionnaire) were registered. Associations between psychological readiness and knee laxity were evaluated with the Spearman rho test, and predictive ability of the ACL-RSI and knee laxity tests were examined using regression analyses.

RESULTS

Of 171 patients screened for eligibility, 132 were included in the study. There were small but significant associations between the ACL-RSI score and the Lachman test (rho = -0.18; P = .046) and KT-1000 arthrometer measurement (rho = -0.18; P = .040) but no association between the ACL-RSI and the pivot-shift test at the time of recruitment. Of the total patients, 36% returned to preinjury sport level by 2 years after surgery. Higher age, better psychological readiness, and less anterior tibial displacement (KT-1000 arthrometer measurement) were significant predictors of 2-year RTS (explained variance, 33%).

CONCLUSION

Small but significant associations were found between measurements of psychological readiness and anterior tibial displacement, indicating that patients with less knee laxity after ACLR feel more ready to RTS. ACL-RSI and KT-1000 arthrometer measurements were independent predictors of 2-year RTS and should be considered in RTS assessments after ACLR.

LEVER SIGN TEST FOR CHRONIC ACL INJURY: A COMPARISON WITH LACHMAN AND ANTERIOR DRAWER TESTS

Objective

This study aims to evaluate the sensitivity and specificity of the lever sign test in patients with and without chronic Anterior Cruciate Ligament (ACL) injuries in an outpatient setting and the inter-examiner agreement of surgeons with different levels of experience.

Methods

72 consecutive patients with a history of previous knee sprains were included. The Lachman, anterior drawer, and Lever Sign tests were performed for all subjects in a randomized order by three blinded raters with different levels of experience. Sensitivity, specificity, positive predictive value, negative predictive value, and inter-rater agreement were estimated for all tests.

Results

Among the 72 patients, the prevalence of ACL injuries was 54%. The lever test showed sensitivity of 64.1% (95% CI 0.47-0.78) and specificity of 100% (95% CI 0.87-1.00) for the senior examiner. For the less experienced examiner the sensitivity was 51.8% and the specificity was 93.7%. Positive predictive values (PPV) and negative predictive values (NPV) were 100% and 70.2%, respectively.

Conclusion

Lever Sign test shows to be a maneuver of easy execution, with 100% specificity and 100% PPV. Moderate agreement between experienced examiners and low agreement among experienced and inexperienced examiners was found. This test may play a role as an auxiliary maneuver. Level of Evidence I, Diagnostic Studies - Investigating a Diagnostic Test.

Multiple ACL Revision: Failure Analysis and Clinical Outcomes

Anterior cruciate ligament (ACL) reconstruction represents one of the most successful orthopedic surgical procedures. Nevertheless, ACL revisions are still very frequent, with a small but relevant number of failures. The purpose of this study is to analyze the failure causes and the clinical outcomes of patients who underwent a re-revision ACL reconstruction. Between January 2009 and December 2017, 263 ACL revisions were performed by a single senior surgeon. Seventeen patients (12 males and 5 females) underwent re-revision ACL reconstruction meeting the inclusion criteria. The mean age was 28.4 years (range, 19-41 years). Before the re-revision, the patients were evaluated preoperatively and after a mean follow-up of 29 months (range, 13-58 months). Assessment included subjective and objective evaluations (Lysholm and International Knee Documentation Committee [IKDC]), KT-2000 arthrometer, radiographic study, and preoperative computed tomography scan. Five patients showed a too anterior previous femoral tunnel and seven a too vertical and posterior tibial tunnel; eight meniscal tears were found. Five patients had grade III-IV according to Outerbridge cartilage lesions. IKDC showed a statistically significant improvement (A + B 35%, C + D 65% preop, A + B 82%, C + D 18% postop, odds ratio: 0.1169; p = 0.0083). The mean Lysholm score ranged from 43 ± 9 to 87 ± 7 (p < 0.001). The KT-2000 arthrometer showed a statistically significant improvement from a mean of 5.8 ± 1.4 to 1.5 ± 1.1 (p < 0.001) at last follow-up. Out of 17 patients, only 4 returned to sports activity at the same preinjury levels. Postoperatively at the last follow-up after last revision surgery, no osteoarthritis evolution was observed. This study showed good clinical and radiological results after the last revision ACL surgery in patients with multiple failures of ACL reconstruction but only one-fourth of the patients returned to the same preoperative sport level. Traumatic events, technical errors, and untreated peripheral lesions are the main causes of multiple previous failures; the worst clinical outcomes were found in the patients with high grade of chondral lesions.

Dynamic ultrasonography in the diagnosis of acute anterior cruciate ligament injury - a case report

In the reported case of acute grade 3 anterior cruciate ligament injury, clinical examination and magnetic resonance imaging findings were in conflict, leading to confusion. Ultimately, dynamic ultrasound imaging proved to be the decisive test. The article describes the steps taken to reach the diagnosis. In addition, possible future diagnostic improvements are discussed. Dynamic ultrasound imaging, performed as part of the physical examination, is a valuable supplement to medical documentation. It provides appreciable diagnostic performance for the detection of anterior cruciate ligament insufficiency. Physical examination combined with magnetic resonance imaging, even though they represent the current diagnostic standard, have their limitations.

A modified anterior drawer test for anterior cruciate ligament ruptures

Objective

This study was aimed to utilize a modified anterior drawer test (MADT) to detect the anterior cruciate ligament (ACL) ruptures and investigate its accuracy compares with three traditional tests.

Methods

Four hundred patients were prospectively enrolled between January 2015 and September 2017 preoperatively to undergo knee arthroscopic surgeries. The MADT, anterior drawer test, Lachman test, and pivot shift test were used in the outpatient clinical setting and were compared statistically for their accuracy in terms of ACL ruptures, with arthroscopic findings as the gold standard.

Results

The prevalence of ACL ruptures in this study was 37.0%. The MADT demonstrated the highest sensitivity (0.89) and accuracy (0.92) among the four tests and had comparable specificity (0.94) and a positive predictive value (0.90) compared with the anterior drawer test, Lachman test, and pivot shift test. The diagnostic odds ratio (DOR) of MADT was 122.92, with other test values of no more than 55.45. The area under the receiver operating characteristic curve (AUC) for the MADT was 0.92 ± 0.01, with a significant difference compared with that for the anterior drawer test (z = 17.00, p < 0.001), Lachman test (z = 9.66, p = 0.002), and pivot shift test (z = 16.39, p < 0.001). The interobserver reproducibility of the MADT was good, with a kappa coefficient of 0.86.

When diagnosing partial tears of ACL, the MADT was significantly more sensitive than the anterior drawer test (p < 0.001), Lachman test (p = 0.026), and pivot shift test (p = 0.013). The MADT showed similar sensitivity in detecting anteromedial and posterolateral bundle tears (p = 0.113) and no difference in diagnosing acute and chronic ACL ruptures (χ² = 1.682, p = 0.195).

Conclusions

The MADT is also an alternative diagnostic test to detect ACL tear, which is equally superior to the anterior drawer test, Lachman test, and pivot shifting test. It could improve the diagnosis of ACL ruptures combined with other clinical information including injury history, clinical examination, and radiological findings.

Levels of evidence

Level II/observational diagnostic studies

Trial registration

Chinese Clinical Trial Registry. ChiCTR1900022945 /retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02381-x.

Association Between Radiological Evidence of Kaplan Fiber Injury, Intraoperative Findings, and Pivot-Shift Grade in the Setting of Acute Anterior Cruciate Ligament Injury

BACKGROUND

Biomechanical studies have suggested that the Kaplan fibers (KFs) of the iliotibial band play a role in controlling anterolateral rotation of the knee. There is a paucity of clinical information on whether injury to the KF in the setting of anterior cruciate ligament (ACL) rupture contributes to increased rotatory laxity of the knee.

PURPOSE/HYPOTHESIS

The purpose was to evaluate the association among radiological evidence of KF injury, intraoperative arthroscopic findings, and grade of pivot shift at the time of ACL reconstruction (ACLR). It was hypothesized that KF injury would be associated with increased injury to the lateral compartment of the knee and a higher grade of pivot shift.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective magnetic resonance imaging (MRI) analysis was conducted on 267 patients with ACL-injured knees who underwent primary ACLR. Patients who had MRI and surgery within 60 days of injury were included (mean age, 23.6 years); there were 158 (59.2%) male patients. MRI was performed using standard knee protocols, and diagnostic criteria were applied to identify KF injury. Associations were made among MRI findings, intraoperative findings, and grade of pivot shift with the patient examined under anesthesia at the time of ACLR. A comparison was made between patients with and without radiological evidence of KF injury.

RESULTS

The prevalence of KF injury was 17.6% (47/267 patients). Arthroscopic evidence of lateral meniscal injury was associated with KF injury (KF intact, 31%; KF injured, 55%; P = .010). The majority of patients in the intact and injured KF groups had a grade 2 pivot shift (75% and 70%, respectively). A minority had grade 3 pivot shift: 5% in the intact group versus 6.4% in the injured group. There was no association between radiological evidence of KF injury and pivot-shift grade (P = .600).

CONCLUSION

In acute ACL injury, KF injuries were not very common (17.6%), and the rate of grade 3 pivot shift was low (5.2%). When present, KF injuries were not associated with a higher-grade pivot shift. However, there was an association between KF injury and lateral meniscal tears identified at the time of ACLR. The role of KFS in controlling anterolateral rotatory laxity in the acute ACL injury in the clinical setting may be less evident when compared with the biomechanical setting.

Asymptomatic Genu Recurvatum reshapes lower limb sagittal joint and elevation angles during gait at different speeds

BACKGROUND

Kinematic characteristics of walking with an asymptomatic genu recurvatum are currently unknown. The objective of this study is to characterize the lower limb sagittal joint and elevation angles during walking in participants with asymptomatic genu recurvatum and compare it with control participants without knee deformation at different speeds.

METHODS

The spatio-temporal parameters and kinematics of the lower limb were recorded using an optoelectronic motion capture system in 26 participants (n = 13 with genu recurvatum and n = 13 controls). The participants walked on an instrumented treadmill during five minutes at three different speeds: slow, medium and fast.

RESULTS

Participants with genu recurvatum showed several significant differences with controls: a narrower step width, a greater maximum hip joint extension angle, a greater knee joint extension angle at mid stance, a lower maximum knee joint flexion angle during the swing phase, and a greater ankle joint extension angle at the end of the gait cycle. Participants with genu recurvatum had a greater minimum thigh elevation angle, a greater maximum foot elevation angle, and a change in the orientation of the covariance plane. Walking speed had a significant effect on nearly all lower limb joint and elevation angles, and covariance plane parameters.

CONCLUSION

Our findings show that genu recurvatum reshapes lower limb sagittal joint and elevation angles during walking at different speeds but preserves the covariation of elevation angles along a plane during both stance and swing phases and the rotation of this plane with increasing speed.

A Comparison of Nonoperative and Operative Treatment of Type 2 Tibial Spine Fractures

Background:

Tibial spine fractures (TSFs) are typically treated nonoperatively when nondisplaced and operatively when completely displaced. However, it is unclear whether displaced but hinged (type 2) TSFs should be treated operatively or nonoperatively.

Purpose:

To compare operative versus nonoperative treatment of type 2 TSFs in terms of overall complication rate, ligamentous laxity, knee range of motion, and rate of subsequent operation.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

We reviewed 164 type 2 TSFs in patients aged 6 to 16 years treated between January 1, 2000, and January 31, 2019. Excluded were patients with previous TSFs, anterior cruciate ligament (ACL) injury, femoral or tibial fractures, or grade 2 or 3 injury of the collateral ligaments or posterior cruciate ligament. Patients were placed according to treatment into the operative group (n = 123) or nonoperative group (n = 41). The only patient characteristic that differed between groups was body mass index (22 [nonoperative] vs 20 [operative]; P = .02). Duration of follow-up was longer in the operative versus the nonoperative group (11 vs 6.9 months). At final follow-up, 74% of all patients had recorded laxity examinations.

Results:

At final follow-up, the nonoperative group had more ACL laxity than did the operative group (P < .01). Groups did not differ significantly in overall complication rate, reoperation rate, or total range of motion (all, P > .05). The nonoperative group had a higher rate of subsequent new TSFs and ACL injuries requiring surgery (4.9%) when compared with the operative group (0%; P = .01). The operative group had a higher rate of arthrofibrosis (8.9%) than did the nonoperative group (0%; P = .047). Reoperation was most common for hardware removal (14%), lysis of adhesions (6.5%), and manipulation under anesthesia (6.5%).

Conclusion:

Although complication rates were similar between nonoperatively and operatively treated type 2 TSFs, patients treated nonoperatively had higher rates of residual laxity and subsequent tibial spine and ACL surgery, whereas patients treated operatively had a higher rate of arthrofibrosis. These findings should be considered when treating patients with type 2 TSF.

Patient-Reported and Quantitative Outcomes of Anatomic Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autografts

Background:

The pivot-shift test has become more consistent and reliable and is a meaningful outcome measurement after anterior cruciate ligament reconstruction (ACLR).

Purpose/Hypothesis:

The purpose of this investigation was to assess patient-reported outcomes (PROs) and the quantitative pivot shift (QPS) preoperatively, at time zero immediately after anatomic ACLR, and after 24 months as well as the relationship between PROs and the QPS. It was hypothesized that anatomic ACLR would restore rotatory stability measured by the pivot-shift test and that QPS measurements would be positively correlated with PROs.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

The ACL-injured and contralateral uninjured knees from 89 of 107 (83.2%) enrolled patients at 4 international centers were evaluated using a standardized pivot-shift test. Tibial acceleration was assessed with an inertial sensor, and lateral compartment translation was measured using an image analysis system preoperatively, at time zero immediately postoperatively, and at follow-up after 2 years. PROs were assessed at 12 and 24 months postoperatively with the International Knee Documentation Committee (IKDC) subjective knee form, Cincinnati Knee Rating System (CKRS), Marx activity rating scale, and activity of daily living score (ADLS).

Results:

The mean patient age at surgery was 27 years (range, 15-45 years). A positive pivot shift preoperatively (side-to-side difference in tibial acceleration, 2.6 ± 4.0 m/s²; side-to-side difference in anterior tibial translation, 2.0 ± 2.0 mm) was reduced at time zero postoperatively (side-to-side difference in tibial acceleration, –0.5 ± 1.3 m/s²; side-to-side difference in anterior tibial translation, –0.1 ± 1.0 mm). All PROs improved from preoperatively to final follow-up at 24 months: from 56.5 to 85.5 points for the IKDC (P = .0001), from 28.8 to 32.4 points for the CKRS (P = .04), from 11.2 to 7.9 points for the Marx (P < .0001), and from 75.7 to 91.6 points for the ADLS (P < .0001). Neither preoperative nor time zero postoperative rotatory laxity assessed by the pivot-shift test correlated with PROs at 24-month follow-up. A graft retear was observed in 4 patients (4.5%) within 2 years of follow-up.

Conclusion:

Anatomic ACLR resulted in significantly improved and acceptable PROs at 2-year follow-up and a low failure rate. Anatomic ACLR restored QPS measurements of anterior tibial translation and tibial acceleration to those of the contralateral knee immediately after surgery while still under anesthesia, but there was no correlation between the QPS preoperatively or at time zero after ACLR and PROs at 2-year follow-up.

Triaxial accelerometer evaluation is correlated with IKDC grade of pivot shift

PURPOSE

The purpose of this study was to evaluate the correlation between tibial acceleration parameters measured by the KiRA device and the clinical grade of pivot shift. The secondary objective was to report the risk factors for pre-operative high-grade pivot shift.

METHODS

Two-hundred and ninety-five ACL deficient patients were examined under anesthesia. The pivot shift tests were performed twice by an expert surgeon. Clinical grading was performed using the International Knee Documentation Committee (IKDC) scale and tibial acceleration data was recorded using a triaxial accelerometer system (KiRA). The difference in the tibial acceleration range between injured and contralateral limbs was used in the analysis. Correlation coefficients were calculated using linear regression. Multivariate logistic regression was used to identify risk factors for high grade pivot shift.

RESULTS

The clinical grade of pivot shift and the side-to-side difference in delta tibial acceleration determined by KiRA were significantly correlated (r = 0.57; 95% CI 0.513-0.658, p < 0.0001). The only risk factor identified to have a significant association with high grade pivot shift was an antero-posterior side to side laxity difference > 6 mm (OR = 2.070; 95% CI (1.259-3.405), p = 0.0042).

CONCLUSION

Side-to-side difference in tibial acceleration range, as measured by KiRA, is correlated with the IKDC pivot shift grade in anaesthetized patients. Side-to-side A-P laxity difference greater than 6 mm is reported as a newly defined risk factor for high grade pivot shift in the ACL injured knee.

DIAGNOSTIC STUDY

Level II.

Three Key Findings When Diagnosing Shoulder Multidirectional Instability: Patient Report of Instability, Hypermobility, and Specific Shoulder Tests

Shoulder instability has varying mechanisms of injury, direction, and severity. Classification systems based on clustering signs and symptoms have been developed to define subgroups of shoulder instability. Despite this attempt at homogeneity, multidirectional instability (MDI) suffers from the same lack of diagnostic clarity as low back pain. In this Viewpoint, the authors outline 3 key areas to address when diagnosing MDI: patient interview, medical comorbidities, and specific shoulder tests and measures. J Orthop Sports Phys Ther 2020;50(2):52-54. doi:10.2519/jospt.2020.0602.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of anterior cruciate ligament injury - Secondary publication

BACKGROUND

This clinical guideline presents recommendations for the management of patients with anterior cruciate ligament (ACL) injury, endorsed by the Japanese Orthopaedic Association (JOA) and Japanese Orthopaedic Society of Knee, Arthroscopy and Sports Medicine (JOSKAS).

METHODS

The JOA ACL guideline committee revised the previous guideline based on "Medical Information Network Distribution Service Handbook for Clinical Practice Guideline Development 2014", which proposed a desirable method for preparing clinical guidelines in Japan. Furthermore, the importance of "the balance of benefit and harm" was also emphasized. This guideline consists of 21 clinical questions (CQ) and 23 background questions (BQ). For each CQ, outcomes from the literature were collected and evaluated systematically according to the adopted study design.

RESULTS

We evaluated the objectives and results of each study in order to make a decision on the level of evidence so as to integrate the results with our recommendations for each CQ. For BQ, the guideline committee proposed recommendations based on the literature.

CONCLUSIONS

This guideline is intended to be used by physicians, orthopedic surgeons, physical therapists, and athletic trainers managing ACL injuries. We hope that this guideline is useful for appropriate decision-making and improved management of ACL injuries.

Anterior tibial displacement on preoperative stress radiography of ACL-injured knee depending on knee flexion angle

Purpose

To compare side-to-side difference (SSD) of anterior tibial translation in instrumented stress radiography for each series of anterior cruciate ligament (ACL)-injured subjects according to knee flexion angle.

Methods

Forty subjects who were suspected of having significant ACL injury by manual Lachman test and MRI were recruited for this prospective study. These subjects took stress radiographs for both knees with corresponding knee flexion of 10° (series M1) and 30° (series M2) using Telos stress device. Mean SSDs of M1 and M2 were compared. Sensitivities of M1 and M2 were assessed using the SSD ≥ 3 mm or ≥ 5 mm as a cutoff value.

Results

Mean SSDs in series M1 and M2 were 4.22 ± 3.72 mm and 3.25 ± 3.30 mm, respectively (p < 0.001). When 3 mm of SSD was used as a cutoff value, sensitivities of series M1 and M2 were 47.5% (19/40) and 32.5% (13/40), respectively (p = 0.171). When 5 mm of SSD was used as a cutoff value, sensitivities of series M1 and M2 were 45.0% (18/40) and 22.5% (9/40), respectively (p = 0.033).

Conclusions

Anterior tibial translation on stress radiographs using a Telos device is more prominent when knee flexion angle is 10° compared to that when knee flexion angle is 30°. However, stress radiography using Telos device, either at 10° or 30° of knee flexion, might not be suitable to make decision on surgical treatment due to relatively low sensitivities.

Implementing the Lever Sign in the Emergency Department: Does it Assist in Acute Anterior Cruciate Ligament Rupture Diagnosis? A Pilot Study

BACKGROUND

Within the emergency department (ED) setting, anterior cruciate ligament (ACL) rupture is commonly misdiagnosed, leading to improper treatment and potential meniscal injury and total joint replacement. Utilizing traditional clinical tests to diagnosis ACL rupture leads to the correct diagnosis in about 30% of cases. The lever sign is a new and effective clinical test used to diagnose ACL rupture with 100% sensitivity.

OBJECTIVE

We aim to study if the lever sign used in the ED setting is more sensitive to diagnose ACL rupture than traditional tests.

METHODS

Patients between 12 and 55 years of age were examined utilizing either traditional methods or the lever sign. Diagnostic findings in the ED were compared with those of a sports medicine specialist using magnetic resonance imaging as the diagnostic standard. A survey was given to ED providers to collect data on diagnosis and physician confidence in diagnosis.

RESULTS

The sensitivity of the lever sign was 100% (94.7% accuracy, 93.75% specificity), whereas the sensitivity of the anterior drawer/Lachman test was 40% (87.5% accuracy, 100% specificity). Physician confidence in diagnosis was higher utilizing the lever sign vs. the anterior drawer/Lachman test at 8.45 (±1.82) compared with 7.72 (±1.82) out of 10, respectively. There was no statistically significant association between diagnostic accuracy with either test and level of training of the ED provider.

CONCLUSION

Implementation of the lever sign in the ED setting resulted in a higher sensitivity, higher physician confidence in screening test diagnosis, and a decrease in the number of undiagnosed ACL ruptures.

Comparison of Diagnostic Accuracy of Physical Examination and MRI in the Most Common Knee Injuries

Purpose: This study evaluated the diagnostic accuracy of physical examination and magnetic resonance imaging (MRI) in knee injuries. Methods: Ninety-six patients at a regional hospital were included in the study. Each participant underwent a physical examination in which menisci and ACL were evaluated. Knee joint MRI was collected from each patient. Physical examination and MRI scans were then compared with knee arthroscopy findings as a golden standard for meniscal and ligamentous lesions. The data were analyzed and specificity and sensitivity were calculated and correlated on receiver operating characteristics (ROC) curves. Results: Knee arthroscopy diagnosed 32 total ACL ruptures, 45 medial meniscus and 17 lateral meniscus lesions. Three patients were diagnosed with bilateral meniscal lesions. The highest sensitivities were the McMurray test (87.5%) for medial meniscus (MM) and the Thessaly test (70%) for lateral meniscus (LM). The most sensitive ACL test was Lachman (84.5%), whereas, the pivot shift and Lelli tests were the most specific (98.5%). MRI was highly sensitive for MM (96%) with specificity of 52%. MRI showed lower sensitivity (70%) and higher specificity (85.5%) for LM. The specificity of MRI for ACL rupture was 92%, with sensitivity only 75%. Conclusion: McMurray and Apley tests for meniscal lesions seem the most appropriate in daily practice. A combination of lever signs, pivot shifts (PSs) and Lachman tests showed the best sensitivity and specificity in detecting ACL deficiency, and was superior to MRI.

Diagnostic Accuracy of Lever Sign Test in Acute, Chronic, and Postreconstructive ACL Injuries

Background

The aim of this study is to determine the diagnostic accuracy of lever sign test in acute, chronic, and postreconstructive ACL injuries.

Methods

In total, 78 patients (69 male, 9 female) were subjected to clinical instability tests including Lachman, anterior drawer, pivot shift, and lever sign when an injury of the ACL was suspected. All tests were performed bilaterally in all patients in acute, chronic period and patients who underwent surgery after the anaesthesia and after the reconstruction at the last follow-up by two senior orthopaedic surgeons. MRI was taken from all patients and MRI image was taken as the reference test when evaluating the accuracy of the tests.

Results

The mean age of patients was 26.2±6.4 years (range, 17-44 years). Sensitivity and accuracy values of the Lachman, anterior drawer, pivot shift, and lever tests in the acute phase were calculated as 80.6%, 77.4%, 51.6%, 91.9% and 76.9%, 75.6%, 60.3%, 92.3%, respectively, and in the chronic (preanaesthesia) phase were calculated as 83.9%, 79.0%, 56.5%, 91.9% and 80.8%, 78.2%, 64.1%, 92.3%, respectively. Lachman, anterior drawer, pivot shift, and lever sign Acute's significant [AUC: 0.716, 0.731, 0.727, 0.928, respectively] activity were observed in the prediction of ACL rupture in MRI.

Conclusion

An ideal test to diagnose the integrity of the ACL should be easy to perform and reproducible with high sensitivity and specificity. From this perspective, the lever test seems to be a good test for clinicians in acute, chronic and postreconstructive ACL injuries.

Allograft tendons are a safe and effective option for revision ACL reconstruction: a clinical review

Revision anterior cruciate ligament reconstruction remains a challenge, especially optimising outcome for patients with a compromised knee where previous autogenous tissue has been used for reconstruction. Allograft tissue has become a recognized choice of graft for revision surgery but questions remain over the risks and benefits of such an option. Allograft tendons are a safe and effective option for revision ACL reconstruction with no higher risk of infection and equivalent failure rates compared to autografts provided that the tissue is not irradiated, or any irradiation is minimal. Best scenarios for use of allografts include revision surgery where further use of autografts could lead to high donor site morbidity, complex instability situations where additional structures may need reconstruction, and in those with clinical and radiologic signs of autologous tendon degeneration. A surgeon needs to be able to select the best option for the challenging knee facing revision ACL reconstruction, and in the light of current data, allograft tissue can be considered a suitable option to this purpose.Level of evidence IV.

Prospective Evaluation of the Patient Acceptable Symptom State to Identify Clinically Successful Anterior Cruciate Ligament Reconstruction

BACKGROUND

The length of most patient-reported outcome measures creates significant response burden, which hampers follow-up rates. The Patient Acceptable Symptom State (PASS) is a single-item, patient-reported outcome measure that asks patients to consider all aspects of life to determine whether the state of their joint is satisfactory; this measure may be viable for tracking outcomes on a large scale.

HYPOTHESIS

The PASS question would identify clinically successful anterior cruciate ligament reconstruction (ACLR) at 1-year follow-up with high sensitivity and moderate specificity. We defined "clinically successful" ACLR as changes in preoperative to postoperative scores on the Knee injury and Osteoarthritis Outcome Score (KOOS) pain subscale and the KOOS knee-related quality of life subscale in excess of minimal clinically important difference or final KOOS pain or knee-related quality of life subscale scores in excess of previously defined PASS thresholds.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

Patients enrolled in a prospective longitudinal cohort completed patient-reported outcome measures immediately before primary ACLR. At 1-year follow-up, patients completed the same patient-reported outcome measures and answered the PASS question: "Taking into account all the activity you have during your daily life, your level of pain, and also your activity limitations and participation restrictions, do you consider the current state of your knee satisfactory?"

RESULTS

A total of 555 patients enrolled in our cohort; 464 were eligible for this study. Of these, 300 patients (64.7%) completed 1-year follow-up, of whom 83.3% reported satisfaction with their knee after surgery. The PASS question demonstrated high sensitivity to identify clinically successful ACLR (92.6%; 95% CI, 88.4%-95.6%). The specificity of the question was 47.1% (95% CI, 35.1%-59.5%). The overall agreement between the PASS and our KOOS-based criteria for clinically successful intervention was 81.9%, and the kappa value indicated moderate agreement between the two methods (κ = 0.44).

CONCLUSION

The PASS question identifies individuals who have experienced clinically successful ACLR with high sensitivity. The limitation of the PASS is its low specificity, which we calculated to be 47.1%. Answering "no" to the PASS question meant that a patient neither improved after surgery nor achieved an acceptable final state of knee health. The brevity, interpretability, and correlation of the PASS question with significant improvements on various KOOS subscales make it a viable option in tracking ACLR outcomes on a national or global scale.

Editorial Commentary: The Anterolateral Ligament Really Exists, Now Show Me How to Find It

The anterior lateral complex is commonly associated with anterior cruciate ligament (ACL) injury. This has been evident since the description of the Segond fracture and by the use of lateral extra-articular tenodesis for ACL injury. Although lateral extra-articular tenodesis has been mostly given up owing to a preference for anatomic ACL reconstructions, it is gaining interest as an adjunct to ACL reconstruction. To determine the need for an anterolateral procedure we need to be able to identify those patients with deficiency in the anterolateral complex. Magnetic resonance imaging is a widely available tool and is typically obtained for every suspected ACL knee injury. Further detailed descriptions of the anterior lateral complex on magnetic resonance imaging can assist in determining accurate indications for anterolateral procedures.

Greater Laxity in the Anterior Cruciate Ligament-Injured Knee Carries a Higher Risk of Postreconstruction Pivot Shift: Intraoperative Measurements With a Navigation System

BACKGROUND

The presence of pivot shift after anterior cruciate ligament (ACL) reconstruction is correlated with worse clinical outcomes. An orthopaedic navigation system is a useful tool for quantifying laxity in the ACL-deficient knee.

PURPOSE

To investigate the relationship between preoperative knee laxity measured by a navigation system and postoperative pivot shift (PPS) after ACL reconstruction.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

One hundred patients who underwent primary ACL reconstruction (62 hamstring tendon grafts, 38 patellar tendon grafts) were grouped according to the presence or absence of pivot shift at the 2-year follow-up, and the groups were compared retrospectively. Before surgery, knee laxity was assessed with a navigation system to quantify posterior tibial reduction (PTR) during pivot-shift tests and anterior tibial translation (ATT) during Lachman tests. PTR and ATT cutoff values were determined by receiver operator characteristic (ROC) analysis.

RESULTS

Preoperative PTR and ATT were significantly larger for patients with PPS (PPS-positive group) than those without (PPS-negative group). In the ROC analysis, the PTR had an area under the curve of 0.871 (95% CI, 0.763-0.979; P < .0001) for predicting a PPS; this was larger than that obtained for the ATT, which had an area under the curve of 0.825 (95% CI, 0.705-0.946; P = .001). Because the ROC curve of the ATT had 2 peaks, the ATT alone was not a suitable predictor for PPS. Based on the ROC curve, the optimal PTR cutoff value was 7 mm, with 88.9% sensitivity and 71.4% specificity for PPS (adjusted odds ratio = 19.7; 95% CI, 2.1-187.9; P = .009). Setting the cutoff value as a combination of the PTR (≧7 mm) and ATT (≧12 mm) improved the specificity (88.9% sensitivity and 84.6% specificity; adjusted odds ratio = 149.8; 95% CI, 5.9-3822.7; P = .002) over that with the PTR alone.

CONCLUSION

ACL injuries in knees with a large PTR had a higher risk of PPS. When reconstructing the ACL in a knee with a high degree of laxity, surgeons may need to adopt strategies to prevent PPS.