Confirming the Presence of Unrecognized Meniscal Injuries on Magnetic Resonance Imaging in Pediatric and Adolescent Patients With Anterior Cruciate Ligament Tears

Effect of Age and Body Mass Index on Time to Advanced Imaging and Surgery in Young Athletes With Anterior Cruciate Ligament Injury

Background

In young athletes with anterior cruciate ligament (ACL) injury, increased times from injury to magnetic resonance imaging (MRI) and injury to surgery can lead to the accrual of new injuries over time.

Purpose

To determine the patient characteristics associated with differences in timing between injury, MRI, and surgery in young athletes with ACL tears.

Study Design

Case-control study; Level of evidence, 3.

Methods

We reviewed the electronic medical records of patients aged 13 to 25 years who underwent isolated primary ACL reconstruction between January 2017 and June 2020 at a single orthopaedic surgery department. The times from injury to MRI, MRI to surgery, and injury to surgery were documented. Patient demographic data (age, sex, body mass index [BMI], race and ethnicity, and insurance type) were recorded. Multivariable analysis was used to determine if any patient characteristic had a significant association with increased time to MRI or surgery.

Results

A total of 369 patients (mean age, 18.0 years; 56% female) were included. Both age and BMI were found to be significantly associated with timing of care while holding all other predictors constant. For every 1-year increase in patient age, time from injury to MRI increased by 9.6 days (95% CI, 1.8-17.4 days; P = .02), time from MRI to surgery increased by 7.4 days (95% CI, 4.4-10.5 days; P < .001), and time from injury to surgery increased by 17.0 days (95% CI, 8.4-25.6 days; P < .001). Compared with patients with normal BMI, overweight patients (BMI range, 25-29.9 kg/m2) had an MRI-to-surgery time that was on average 37.2 days (95% CI, 11.7-62.7 days; P < .004) longer and an injury to surgery time that was on average 71.8 days (95% CI, 0.5-143.0 days; P = .048) longer. Obese patients (BMI ≥30 kg/m2) did not demonstrate a significant relationship with the studied time intervals.

Conclusion

Increasing age and elevated BMI were found to be associated with increased time to MRI and surgical care in young athletes with ACL injuries.

Accuracy of needle arthroscopy for the diagnosis of medial meniscal tears in dogs with cranial cruciate ligament rupture

OBJECTIVE

To determine the accuracy of needle arthroscopy (NA) for the diagnosis of medial meniscal tears in dogs with cranial cruciate ligament rupture (CCLR).

STUDY DESIGN

Prospective clinical trial.

ANIMALS

Twenty-six client-owned dogs.

METHODS

Dogs with CCLR and scheduled to undergo tibial plateau leveling osteotomy were recruited for the study. Needle arthroscopy was performed by an experienced surgeon; the same dog subsequently underwent standard arthroscopy (SA) by another experienced surgeon who was blinded to the NA findings. The SA arthroscopy findings were used as the gold standard. Arthroscopy time, visibility of the menisci, ability to probe the menisci, and the presence of meniscal tears were recorded for both arthroscopies. The degree of lameness before and after NA was subjectively quantified.

RESULTS

The sensitivity and specificity to diagnose medial meniscal tears with NA was 95% and 100%, respectively. Visibility of the menisci was lower (P < .01), probing of the lateral meniscus was harder (P = .0017), and procedure time was shorter (P = .073) with NA when compared to SA. The lameness scores did not differ before and after NA (P = .25).

CONCLUSION

Needle arthroscopy could be performed rapidly with low morbidity, and had high accuracy for detecting medial meniscal tears in dogs with CCLR.

CLINICAL SIGNIFICANCE

Needle arthroscopy is a promising minimally invasive technique for diagnosing medial meniscal tears in dogs with CCLR.

Clinical Examination in the Diagnosis of Anterior Cruciate Ligament Injury: A Blinded, Cross-sectional Evaluation

OBJECTIVE

This study was conducted to compare the effectiveness of clinical tests for anterior cruciate ligament (ACL) injury.

METHODS

This study prospectively evaluated the effectiveness of the Lachman test, anterior drawer test, and lever test in diagnosing ACL injury in 133 patients with knee pathology. The examiner was blinded to the patient's history, symptoms, and laterality of the pain at the time of examination. One hundred twenty-three patients in the study underwent MRI, and 90 went on to arthroscopy. The performance of the examination maneuvers and MRI was calculated.

RESULTS

This study showed notable differences in sensitivity and specificity between the Lachman test and the lever test and in specificity between the anterior drawer test and the lever test. The Lachman test was also found to be more sensitive than the anterior drawer. All ACL tears diagnosed by a composite of the physical examination maneuvers were confirmed by MRI. MRI findings were concordant with arthroscopic findings in all cases.

CONCLUSIONS

The Lachman test and the anterior draw test demonstrated clinical utility, but the results of the lever test should be interpreted with caution. Clinical examination was found to be highly specific but less sensitive than MRI.

Effect of Increased Time to Surgery on the Ability of MRI to Rule Out Medial Meniscal Tears in Young Athletes With ACL Injury

Background

The prevalence of meniscal tears in patients with anterior cruciate ligament (ACL) injury increases with extended time between injury and ACL reconstruction.

Purpose/Hypothesis

The purpose of this study was to determine if there is a relationship between time from magnetic resonance imaging (MRI) to ACL reconstruction and the predictive value of MRI to diagnose meniscal tears in the young active population. It was hypothesized that increased time between MRI and ACL reconstruction would lead to a decrease in the negative predictive value of MRI in diagnosing meniscal tears, as more injuries may accrue over time in the ACL-deficient knee.

Study Design

Case series; Level of evidence, 4.

Methods

Included were patients aged 13 to 25 years at the authors' institution who underwent primary ACL reconstruction from January 2017 to June 2020. Time from MRI to surgery as well as descriptions of medial and lateral meniscal tears on both MRI and operative reports were documented. Time from MRI to surgery was divided into 4 intervals: 0 to 6 weeks, >6 weeks to 3 months, >3 to 6 months, and beyond 6 months. Multivariable analysis was used to determine the positive and negative predictive values of MRI in diagnosing a meniscal tear as compared with arthroscopic findings.

Results

A total of 432 patients were included with a mean age of 17.9 ± 3.4 years. The mean time from MRI to surgery was 70.5 ± 98 days. There was a significant decrease in the negative predictive value of MRI to identify a medial meniscal tear in patients who underwent ACL reconstruction >6 months after imaging (odds ratio, 0.16 [95% CI, 0.05-0.53]; P = .003). This same relationship was not shown for lateral meniscal tears, nor was any other predictor significant.

Conclusion

The utility of MRI to rule out a medial meniscal tear significantly diminished in the young athletic population when >6 months passed between MRI and ACL reconstruction. These data suggest these tears occur between the time of the MRI and surgery and that the medial meniscus is more susceptible than the lateral meniscus to new injury once the ACL has torn.

A basic study for the molecular imaging of dual-energy CT in diagnosing anterior cruciate ligament injury of knee joint

Background

Anterior cruciate ligament (ACL) injury is a common disease in clinical practice that seriously affects the daily life of patients.

Purpose

To explore the molecular imaging basis of “diminution sign on dual-energy colour mapping” for the diagnosis of ACL injury by dual-energy computed tomography (DECT).

Material and Methods

The hydroxylysine and hydroxyproline reagents were prepared in different concentrations. The grouping was shown as follows: a simple concentration change group of an amino acid (group 1/2); a mixed solution group with the concentration increasing synchronously (group 3); a mixed solution group with the concentration reverse increasing and decreasing (group 4); and a mixed solution group that fix one amino acid with increasing concentration of the other (group 5/6). The samples were scanned by DECT. The solution CT value and image signal-to-noise ratio were analyzed.

Results

In group 1/2, the brightness of the dual-energy color mapping of each test tube solution and the CT value increased with increasing the concentration of amino acid. In group 6, there was no significant change in the brightness and brilliance of the dual-energy color mapping and the CT value. The remaining three groups showed an increase in the brightness and brilliance of the dual-energy color mapping and the CT value, and this increase was positively associated with the hydroxylysine concentration.

Conclusion

The dual-energy staining of the DECT imaging in “tendon” mode is related to hydroxylysine and hydroxyproline. Moreover, the degree of dual-energy color mapping is positively correlated with the change of CT value.

Magnetic Resonance Imaging of Lateral Meniscus Root Tears in the Pediatric and Adolescent Knee: Is the Diagnosis Missed, Mentioned, or Made?

Background

Failure to address meniscus root tears may place undue loads on anterior cruciate ligament (ACL) reconstructive surgery in the adult population. Because the intraoperative management of lateral meniscus posterior root tears (LMPRTs) may diverge from standard meniscal work and requires specialty items, preoperative diagnosis may be advantageous.

Purpose

To evaluate the reliability of radiologist interpretations of preoperative knee magnetic resonance imaging (MRI) scans of lateral meniscus root pathology in a mixed pediatric and adolescent population.

Study Design

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

Methods

A retrospective review of medical records was performed to identify patients younger than 18 years with an arthroscopically confirmed LMPRT who underwent knee arthroscopy between March 1, 2010, and April 1, 2020. Arthroscopic findings were compared with the reading radiologist's preoperative MRI interpretations, and patients were stratified into 2 groups: (1) LMPRT diagnosis made preoperatively or (2) diagnosis missed or only mentioned to describe pathology nonspecific to the root. Variables such as body mass index (BMI), open physes, time from injury to MRI, time from MRI to surgery, MRI magnet field strength, musculoskeletal radiologist designation, insurance type, and tear grade were assessed between groups.

Results

Overall, 1116 knee arthroscopies were performed, with 49 LMPRTs found; all 49 LMRPTs were found concomitantly with ACL tears (49/535; 9.2%). The average patient age was 15.97 years (range, 11.52-17.97 years). There were 50 MRI scans for 49 patients. An LMPRT was diagnosed based on preoperative MRI scans in 12 of these 50 scans (24%) and mentioned or missed in 38 of the 50 scans (76%). No significant difference was seen between the diagnosis-made versus diagnosis-mentioned/missed groups in BMI, skeletal maturity, time from injury to MRI, time from MRI to surgery, MRI magnet strength, fellowship training of the reading radiologist, tear grade, or insurance type.

Conclusion

In 76% of patients, a definitive diagnosis of LMPRT was not made on preoperative MRI scans. Notably, all LMPRTs found intraoperatively were found concomitantly with ACL tears.

Paediatric Anterior Cruciate Ligament (ACL) Injuries: Current Concepts Review

BACKGROUND

Over the past two decades, there has been a documented increase in paediatric ACL injuries because of a rise in younger age sports participation at the competitive level, awareness about sports-related injuries, and advanced imaging modalities.

METHODS

A PubMed electronic database search was done, which revealed 1366 hits over the last five years (2016 - 2020). Finally, 37 articles that contributed to new findings were included. This review was conducted based on predefined research questions.

RESULTS AND CONCLUSION

Early surgical reconstruction is recommended in children due to the increasing demand for early return to sports and to prevent the instability that can lead to progressive cartilage and meniscal damage. With the evolution of several "physeal sparing" ACL reconstruction (ACLR) techniques, a favorable clinical outcome with less growth disturbance is achievable. Although different autograft options are available, hamstring autografts are most commonly preferred. A specific pattern of a bone bruise not extending into the metaphysis, and lateral meniscus tears are the most common associated injuries. Following paediatric ACLR, complications like graft rupture and contralateral ACL injuries are two to three folds higher than with adult ACLR. Unprepared early return to sports is one of the reasons for increased complication rates in children; thus, clearance criteria for return to sports need to be standardized, and early return to sports (< 9 months post ACLR) should be avoided. Neuromuscular training protocols are recommended to minimize complications like graft ruptures.

Sensitivity and Specificity of MRI in Diagnosing Concomitant Meniscal Injuries With Pediatric and Adolescent Acute ACL Tears

Background:

Preoperative diagnosis of concomitant meniscal tears in pediatric and adolescent patients with acute anterior cruciate ligament (ACL) deficiency is challenging.

Purpose:

To investigate the diagnostic performance of magnetic resonance imaging (MRI) in detecting meniscal injuries for pediatric and adolescent patients with acute ACL tears.

Study Design:

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

Methods:

The authors retrospectively identified patients aged ≤18 years who underwent acute ACL reconstruction between 2006 and 2018 at 2 tertiary academic hospitals. The primary outcomes were arthroscopically confirmed medial, lateral, or any (defined as medial and/or lateral) meniscal tears. To control for chronically deficient knees, patients must have received their MRI study within 4 weeks of injury and must have undergone surgery no more than 8 weeks after their MRI study. Preoperative MRI reports were compared with the gold standard of arthroscopically confirmed tears to calculate sensitivity, specificity, positive predictive value, and negative predictive value. In a secondary analysis, patients were stratified by age into 2 groups (≤13 or ≥14 years), body mass index-for-age data from the Centers for Disease Control were used to classify patients as obese or nonobese, and differences between sensitivity and specificity proportions were analyzed using chi-square test for homogeneity.

Results:

Overall, 406 patients with a mean age of 15.4 years (range, 10-18 years) were identified. The sensitivity, specificity, positive predictive value, and negative predictive value were as follows: for lateral meniscal (LM) tears, 51.0%, 86.5%, 78.3%, and 65.0%; for medial meniscal tears, 83.2%, 80.6%, 62.3%, and 92.5%; and for any meniscal tear, 75.0%, 72.1%, 81.5%, and 63.8%, respectively. In the stratified analysis, MRI was less specific for the following diagnoses: any meniscal tear in patients aged ≤13 years (P = .048) and LM tears in obese patients (P = .020).

Conclusion:

The diagnostic ability of MRI to predict meniscal injuries present at acute ACL reconstruction was moderate. Performance was poorest at the lateral meniscus, where MRI failed to detect 97 tears that were found arthroscopically. Specificity was significantly lower in younger patients for any meniscal tear and in obese patients for LM tears.

Elevated BMI increases concurrent pathology and operative time in adolescent ACL reconstruction

PURPOSE

The purpose of this study was to (1) report on the incidence of concurrent surgical pathology at the time of adolescent ACL reconstruction, (2) evaluate patient risk factors for concurrent pathology, and (3) measure the effect of BMI on operating room (OR) time.

METHODS

A retrospective analysis of the NSQIP database for the years 2005-2017 was conducted. Nine-hundred and seventeen patients 18 years of age and younger who underwent ACL reconstruction (ACLR) were identified using CPT code 29888 and patients undergoing surgery for multi-ligamentous knee injuries were excluded. The mean patient age was 17.6 years (range 14-18, standard deviation 0.52) and consisted of 546 males (59.5%) and 371 females (40.5%). Logistic regression was used to assess the relationship between BMI and additional CPT codes for internal derangement at the time of surgery. Internal derangement was defined as any procedure for the treatment of a meniscal tear, chondral lesion, or loose body removal. Linear regression analysis was then performed to evaluate the effect of BMI on operative time.

RESULTS

43.7% of patients undergoing ACLR required an associated procedure for internal derangement. Additionally, the risk of requiring additional procedures for internal derangement increased by 3.1% per BMI point. BMI was also predictive of operative time, independent of the number of additional procedures. Specifically, the operative time increased by nearly one minute for every point increase in BMI (58.0 s).

CONCLUSIONS

Adolescent patients with an elevated BMI were much more likely to require additional surgical procedures for internal derangement at the time of ACL reconstruction. Additionally, BMI was a significant predictor for longer operative times.

LEVEL OF EVIDENCE

Level III.

Is meniscal status in the anterior cruciate ligament injured knee associated with change in bone surface area? An exploratory analysis of the KANON trial

OBJECTIVES

To study bone shape changes as a potential early feature of post-traumatic structural knee OA development, we estimated the association between meniscal status in the anterior cruciate ligament (ACL) injured knee and longitudinal condyle changes in bone surface area.

DESIGN

We used data from the KANON trial, including 121 young ACL-injured adults. We obtained baseline and 2-year follow-up knee MRIs. Our outcome was change in the bone surface areas (mean mm2, log-transformed) in 4 locations (femur, tibia, patella, and trochlea femur) in the medial and lateral compartment from baseline to 2 years. Meniscal pathology was defined as both present at baseline and newly developed (i.e., incident or progressed) using ACLOAS. We used multilevel linear regression adjusted for baseline bone area, age, sex, body mass index, treatment arm (i.e., early or optional delayed ACL reconstruction), and location. We analyzed medial and lateral compartment separately. We present results as percentage (%) bone area change difference with 95% confidence intervals (CI).

RESULTS

We analyzed 109 subjects (median 27 (18-36) years, 83% men) due to missing MRI information. The bone surface area increased on average by ∼2% over 2 years. The differences between knees with and without baseline meniscal pathology were 1.1% (95%CI 0.0-2.3%) and 1.4% (95%CI 0.6-2.2%) in the medial and lateral compartment, respectively, and 1.2% (95%CI 0.3-2.0%) and 1.3% (95%CI 0.6-2.0%) for medial and lateral newly developed pathology, respectively.

CONCLUSION

Our finding of ∼1% increase bone area in compartment with meniscal pathology suggests a potentially important association between meniscal integrity and early bone surface area changes after ACL injury. Trial registration number ISRCTN 84752559.

Rates of Concomitant Meniscal Tears in Pediatric Patients With Anterior Cruciate Ligament Injuries Increase With Age and Body Mass Index

Background

Anterior cruciate ligament (ACL) tears are frequently associated with meniscal injury. Risk factors for concomitant meniscal injuries have been studied in the adult population but less so in pediatric patients.

Purpose

To evaluate the relationship between age and body mass index (BMI) and the presence of a concomitant meniscal tear at the time of ACL reconstruction (ACLR) in pediatric patients.

Study Design

Case-control study; Level of evidence, 3.

Methods

A single-institution retrospective review was performed of patients aged <19 years who underwent primary ACLR over a 3.5-year period. Revision ACLR and multiligament knee reconstructions were excluded. Logistic regression was used to identify risk factors associated with having a meniscal tear at the time of surgery. Subgroup analysis was performed for medial and lateral meniscal tears.

Results

Included in this study were 453 patients (230 males, 223 females; median age, 15 years). Of these, 265 patients (58%) had a meniscal tear, including 150 isolated lateral meniscal tears, 53 isolated medial meniscal tears, and 62 patients with both lateral and medial meniscal tears. Median time from injury to surgery was 48 days. For every 1-year increase in age, there was a 16% increase in the adjusted odds of having any meniscal tear (odds ratio [OR], 1.16; 95% confidence interval [CI], 1.05-1.27; P = .002), with a 20% increase in the odds of having a medial meniscal tear (OR, 1.20; 95% CI, 1.07-1.35; P = .002) and a 16% increase in the odds of having a lateral meniscal tear (OR, 1.16; 95% CI, 1.05-1.27; P = .003). For every 2-point increase in BMI, there was a 12% increase in the odds of having any meniscal tear (OR, 1.12; 95% CI, 1.02-1.22; P = .016) and a 10% increase in the odds of having a lateral meniscal tear (OR, 1.10; 95% CI, 1.01-1.19; P = .028).

Conclusion

Pediatric patients undergoing ACLR had a 58% incidence of concomitant meniscal pathology. Increasing age and BMI were independent risk factors for these injuries, while no association was found between time to surgery and meniscal pathology.

Near-Infrared Spectroscopy for Mapping of Human Meniscus Biochemical Constituents

Degenerative changes in meniscus are diagnosed during surgery by means of mechanical testing and visual evaluation. This method is qualitative and highly subjective, providing very little information on the internal state of the meniscus. Thus, there is need for novel quantitative methods that can support decision-making during arthroscopic surgery. In this study, we investigate the potential of near-infrared spectroscopy (NIRS) for mapping the biochemical constituents of human meniscus, including water, uronic acid, and hydroxyproline contents. Partial least squares regression models were developed using data from 115 measurement locations of menisci samples extracted from 7 cadavers and 11 surgery patient donors. Model performance was evaluated using an independent test set consisting of 55 measurement locations within a meniscus sample obtained from a separate cadaver. The correlation coefficient of calibration (ρ_training), test set (ρ_test), and root-mean-squared error of test set (RMSEP) were as follows: water (ρ_training = 0.61, ρ_test = 0.39, and RMSEP = 2.27 percentage points), uronic acid (ρ_training = 0.68, ρ_test = 0.69, and RMSEP = 6.09 basis points), and hydroxyproline (ρ_training = 0.84, ρ_test = 0.58, and error = 0.54 percentage points). In conclusion, the results suggest that NIRS could enable rapid arthroscopic mapping of changes in meniscus biochemical constituents, thus providing means for quantitative assessment of meniscus degeneration.