Popliteal scoring assessment for vascular extremity injuries in trauma study.

OBJECTIVE: Traumatic popliteal vascular injuries are associated with the highest risk of limb loss of all peripheral vascular injuries. A method to evaluate the predictors of amputation is needed because previous scores could not be validated. In the present study, we aimed to provide a simplified scoring system (POPSAVEIT [popliteal scoring assessment for vascular extremity injuries in trauma]) that could be used preoperatively to risk stratify patients with traumatic popliteal vascular injuries for amputation. METHODS: A review of patients sustaining traumatic popliteal artery injuries was performed. Patients requiring amputation were compared with those with limb salvage at the last follow-up. Of these patients, 80% were randomly assigned to a training group for score generation and 20% to a testing group for validation. Significant predictors of amputation (P < .1) on univariate analysis were included in a multivariable analysis. Those with P < .05 on multivariable analysis were assigned points according to the relative value of their odds ratios (ORs). Receiver operating characteristic curves were generated to determine low- vs high-risk scores. An area under the curve of >0.65 was considered adequate for validation. RESULTS: A total of 355 patients were included, with an overall amputation rate of 16%. On multivariate regression analysis, the risk factors independently associated with amputation in the final model were as follows: systolic blood pressure <90 mm Hg (OR, 3.2; P = .027; 1 point), associated orthopedic injury (OR, 4.9; P = .014; 2 points), and a lack of preoperative pedal Doppler signals (OR, 5.5; P = .002; 2 points [or 1 point for a lack of palpable pedal pulses if Doppler signal data were unavailable]). A score of ≥3 was found to maximize the sensitivity (85%) and specificity (49%) for a high risk of amputation. The receiver operating characteristic curve for the validation group had an area under the curve of 0.750, meeting the threshold for score validation. CONCLUSIONS: The POPSAVEIT score provides a simple and practical method to effectively stratify patients preoperatively into low- and high-risk major amputation categories.

Decision Tree Learning Algorithm for Classifying Knee Injury Status Using Return-to-Activity Criteria.

Anterior cruciate ligament (ACL) injury rates in female adolescents are increasing. Irrespective of treatment options, approximately 1/3 will suffer secondary ACL injuries following their return to activity (RTA). Despite this, there are no evidence-informed RTA guidelines to aid clinicians in deciding when this should occur. The first step towards these guidelines is to identify relevant and feasible measures to assess the functional status of these patients. The purpose of this study was therefore to evaluate tests frequently used to assess functional capacity following surgery using a Reduced Error Pruning Tree (REPT). Thirty-six healthy and forty-two ACLinjured adolescent females performed a series of functional tasks. Motion analysis along with spatiotemporal measures were used to extract thirty clinically relevant variables. The REPT reduced these variables down to two limb symmetry measures (maximum anterior hop and maximum lateral hop), capable of classifying injury status between the healthy and ACL injured participants with a 69% sensitivity, 78% specificity and kappa statistic of 0.464. We, therefore, conclude that the REPT model was able to evaluate functional capacity as it relates to injury status in adolescent females. We also recommend considering these variables when developing RTA assessments and guidelines.Clinical Relevance- Our results indicate that spatiotemporal measures may differentiate ACL-injured and healthy female adolescents with moderate confidence using a REPT. The identified tests may reasonably be added to the clinical evaluation process when evaluating functional capacity and readiness to return to activity.

Multiple Ligament Injured Knee: Initial Assessment and Treatment.

The multiple ligament injured knee (knee dislocation) is oftentimes part of a multisystem injury complex that can include injuries not only to knee ligaments but also to blood vessels, skin, nerves, bones (fractures), head, and other organ system trauma. These additional injuries can affect surgical timing for knee ligament reconstruction and also affect the results of treatment. This article presents the author's approach and experience to the initial assessment and treatment of the multiple ligament injured (dislocated) knee.

Cost-Effectiveness Analysis of Needle Arthroscopy Versus Magnetic Resonance Imaging in the Diagnosis and Treatment of Meniscal Tears of the Knee.

PURPOSE: To determine whether needle arthroscopy (NA) compared with magnetic resonance imaging (MRI) in the diagnosis and treatment of meniscal tears is cost-effective when evaluated over a 2-year period via patient-reported outcomes. The hypothesis is that improved diagnostic accuracy with NA would lead to less costly care and similar outcomes. METHODS: A Markov model/decision tree analysis was performed using TreeAge Pro 2017 software. Patients were evaluated for degenerative and traumatic damage to the lateral/medial meniscus. Assumed sensitivities and specificities were derived from the medical literature. The direct costs for care were derived from the 2017 Medicare fee schedule and from private payer reimbursement rates. Costs for care included procedures performed for false-positive findings and for care for false-negative findings. Effectiveness was examined using the global knee injury and osteoarthritis outcome score (KOOS). Patients were evaluated over 2 years for costs and outcomes, including complications. Dominance and incremental cost-effectiveness were evaluated, and 1- to 2-way sensitivity analysis was performed to determine those variables that had the greatest effect. The consolidated economics evaluation and reporting standards checklist for reporting economic evaluations was used. RESULTS: NA was less costly and had similar KOOS versus MRI for both the medial/lateral meniscus with private pay. Costs were less for both Medicare and private pay for medial meniscus, $780 to $1,862, and lateral meniscus, $314 to $1,256, respectively. CONCLUSIONS: Based on the reported MRI incidence of false positives with the medial meniscus and false negatives with the lateral meniscus and based on assumed standards of care, more costly care is provided when using MRI compared with NA. Outcomes were similar with NA compared with MRI. LEVEL OF EVIDENCE: Level II, economic and decision analysis.

Pure intervention effect or effect in routine health care - blinded or non-blinded randomized controlled trial.

BACKGROUND: Randomized trials provide the most valid evidence of effectiveness of interventions. The study aims to determine the primary study question for randomized controlled trials; to evaluate the study questions in trials on effectiveness of arthroscopic meniscectomy for meniscal rupture of the knee; and to explore the clinical and research implications. METHODS: Previous studies on benchmarking controlled trials were utilized. A literature search was undertaken to find the trials on arthroscopic surgery for meniscal rupture of the knee, data was extracted, and checked for accuracy twice. RESULTS: The first question in RCTs is whether to assess the pure intervention effect, or intervention effect in routine health care circumstances. The former necessitates a double blinded design and the latter a non-blind design. The trials on arthroscopic meniscectomy of the knee showed considerable differences in study characteristics. CONCLUSIONS: The study question in RCTs on pure intervention effect dictates use of blinded design, while question of intervention effect in routine health care dictates use of non-blinded design. Blinding should not be considered a validity criterion when study question is on effectiveness in routine health care. When informing patients, the potential for other effects besides the pure intervention effect should be considered.

A systematic review of self-administered questionnaires for the functional assessment of patients with knee disabilities adapted into Spanish. / Revisión sistemática de los cuestionarios autocumplimentados adaptados al español para la valoración funcional de pacientes con afecciones de rodilla.

OBJECTIVE: The aim of this study was to conduct a systematic review of self-administered knee-disability functional assessment questionnaires adapted to Spanish, analysing the quality of the transcultural adaptation procedure and the psychometric properties of the new version. MATERIAL AND METHODS: A search was conducted in the main biomedical databases to find knee-function assessment scales adapted into Spanish, in order to assess their questionnaire adaptation process as well as their psychometric properties. RESULTS: Ten scales were identified; 3 for lower limb: 2 for any type of pathologies (Lower Limb Functional Index [LLFI]; Lower Extremity Functional Scale [LEFS]) and 1 specific for arthrosis (Arthrosis des Membres Inférieurs et Qualité de vie [AMICAL]); Other 3 for knee and hip pathologies (Western Ontario and McMaster Universities Osteoarthritis [WOMAC] index; Osteoarthritis Knee and Hip Quality of Life [OAKHQOL] questionnaire; Hip and Knee Questionnaire [HKQ]), and other 4 for knee: 2 general scales (Knee Injury and Osteoarthritis Outcome Score [KOOS]; Knee Society Clinical Rating System [KSS]) and 2 specifics (Victorian Institute of Sport Assessment [VISA-P] questionnaire for patients with patellar tendinopathy and Kujala Score for patellofemoral pain). The transcultural adaptation procedure was satisfactory, albeit somewhat less rigorous for HKQ and LLFI. In no study were all psychometric properties assessed. Reliability was analyzed in all cases, except in KSS. Validity was measured in all questionnaires. CONCLUSIONS: The transcultural adaptation procedure was satisfactory and the psychometric properties analysed were similar to both the original version and other versions adapted to other languages.

Assessment of knee laxity using a robotic testing device: a comparison to the manual clinical knee examination.

PURPOSE: The purpose of this study was to collect knee laxity data using a robotic testing device. The data collected were then compared to the results obtained from manual clinical examination. METHODS: Two human cadavers were studied. A medial collateral ligament (MCL) tear was simulated in the left knee of cadaver 1, and a posterolateral corner (PLC) injury was simulated in the right knee of cadaver 2. Contralateral knees were left intact. Five blinded examiners carried out manual clinical examination on the knees. Laxity grades and a diagnosis were recorded. Using a robotic knee device which can measure knee laxity in three planes of motion: anterior-posterior, internal-external tibia rotation, and varus-valgus, quantitative data were obtained to document tibial motion relative to the femur. RESULTS: One of the five examiners correctly diagnosed the MCL injury. Robotic testing showed a 1.7° larger valgus angle, 3° greater tibial internal rotation, and lower endpoint stiffness (11.1 vs. 24.6 Nm/°) in the MCL-injured knee during varus-valgus testing when compared to the intact knee and 4.9 mm greater medial tibial translation during rotational testing. Two of the five examiners correctly diagnosed the PLC injury, while the other examiners diagnosed an MCL tear. The PLC-injured knee demonstrated 4.1 mm more lateral tibial translation and 2.2 mm more posterior tibial translation during varus-valgus testing when compared to the intact knee. CONCLUSIONS: The robotic testing device was able to provide objective numerical data that reflected differences between the injured knees and the uninjured knees in both cadavers. The examiners that performed the manual clinical examination on the cadaver knees proved to be poor at diagnosing the injuries. Robotic testing could act as an adjunct to the manual clinical examination by supplying numbers that could improve diagnosis of knee injury. LEVEL OF EVIDENCE: Level II.

Assessment of Knee Joint Injuries with Low Field Strength Magnetic Resonance Imaging.

BACKGROUND: Magnetic Resonance Imaging is an appropriate screening tool before therapeutic arthroscopy, making diagnostic arthroscopy unnecessary in most patients. This study aims to evaluate the MRI findings in knee injuries and diagnostic value of low Strength MRI for assessing Meniscal and cruciate ligament tear. METHODS: A cross sectional study was conducted on patients undergoing "Magnetic Resonance Imaging of the Knee" for injuries of the knee and excluded patients undergoing MRI for other causes, poor diagnostic quality MRI and post operative MRI. All patients were interviewed for mechanism of injury and followed up for arthroscopic findings. Statistical analysis was doe using IBM SPSS 20.0. RESULTS: A total of 81 MRIs was included in the study. Arthroscopic finding of only 32 patients could be followed up. Anterior cruciate ligament (ACL) tear was the most common internal ligament tear accounting for 34(42%) of cases followed by medial meniscus tear in 33(40.7%). Twisting 14( 42.4%)was the most common mechanism involved in medial meniscus tear while combined mechanism of injury was most common mechanism for ACL tear 16( 47.05%). The sensitivity of MRI for diagnosis of ACL tear and medial meniscus tear was 96.3% and 94.7% respectively. Specificity for ACL tear was however only 80% and that for medial meniscus tear was 100%. CONCLUSIONS: The diagnostic value of MRI for diagnosing internal derangement of knee was high even with a low Tesla (0.3 T) MRI thus emphasizing the role of MRI as a non-invasive alternative to diagnostic arthroscopy.

[Incidence of knee injuries : Numbers for outpatient and inpatient care in Germany]. / Inzidenz von Kniegelenkverletzungen : Zahlen für die ambulante und stationäre Versorgung in Deutschland.

BACKGROUND: Musculoskeletal illnesses and injuries are among the most common ailments in the Federal Republic of Germany. In 2008 they generated costs of nearly 29 billion euros. Figures about their incidence and prevalence are necessary for a demand-oriented planning of future patient-centred care. METHOD: Pseudonymised data of 3.8 million people insured by AOK Baden-Württemberg between 2008 and 2013 were evaluated. The diagnoses were assigned to nine injury groups. For outpatient care confirmed diagnoses were considered, and for inpatient care both primary and secondary diagnoses were considered. For all patients with structural knee injuries, it was evaluated whether they made use of one of five eligible treatment paradigms either in the quarter in which they were injured or in the following quarter. RESULTS: 418,257 patients were treated in 2013 for at least one new-onset injury (10.9 % of all insurees); 86,783 insurees (2.3 % of all insurees) had a newly occurring knee injury. The vast majority of the patients were treated by specialist doctors. While magnetic resonance imaging clearly increased during the observation period, the incidence of surgical therapy did not change. Striking are the different age distributions regarding the types of injuries, with a high injury incidence amongst young men and a significant increase in injuries between 2008 and 2013, especially amongst women. CONCLUSION: For the first time, the data quantify the knee injury incidences of a large cohort in Germany. They show which inpatient and outpatient health care services have been claimed and that an age- and gender-adapted prevention and an increased awareness are needed.

Chinese adaptation and validation of the Knee Injury and Osteoarthritis Outcome Score (KOOS) in patients with knee osteoarthritis.

Knee Injury and Osteoarthritis Outcome Score (KOOS) is a commonly used instrument to assess the symptoms and functional status in people with knee injuries, including knee osteoarthritis. While China ranked the top country in the absolute number of people aged 65 or above, yet there is no validated Chinese version of this outcome measurement. This study translated and validated the KOOS into Chinese version. Chinese KOOS was translated from the original English version following standard forward and backward translation procedures recommended by the International Society for Pharmacoeconomics and Outcomes Research. Survey was then conducted in clinical settings by a questionnaire comprised Chinese KOOS, WOMAC Osteoarthritis Index, and Short Form 36 health survey (SF-36). One hundred Chinese reading patients with knee osteoarthritis were recruited from the orthopaedic out-patient department in hospitals. Internal consistency of the instrument was measured by Cronbach alpha. Construct validity was examined by Spearman's rank correlation coefficient (ρ) tests by comparing its score with the validated Chinese version of WOMAC Osteoarthritis Index and SF-36, while the test-retest reliability was evaluated by administering the questionnaires twice. Cronbach alpha values of individual questions and its overall value were above 0.70. Fairly strong association was found between the Chinese KOOS and the WOMAC Osteoarthritis Index (ρ = -0.37 to -0.86, p < 0.001). Diverse relationship was observed between Chinese KOOS and SF-36. Excellent test-retest reliability (ICC = 0.89-0.92) was demonstrated. The Chinese translated version of KOOS is a reliable and valid instrument for patients with knee osteoarthritis. The findings of current study might promote multinational investigations in this patient group.

Reliability of a field-based drop vertical jump screening test for ACL injury risk assessment.

OBJECTIVES: There is an epidemic of anterior cruciate ligament (ACL) injuries in youth athletes. Poor neuromuscular control is an easily modifiable risk factor for ACL injury, and can be screened for by observing dynamic knee valgus on landing in a drop vertical jump test. This study aims to validate a simple, clinically useful population-based screening test to identify at-risk athletes prior to participation in organized sports. We hypothesized that both physicians and allied health professionals would be accurate in subjectively assessing injury risk in real-time field and office conditions without motion analysis data and would be in agreement with each other. METHODS: We evaluated the inter-rater reliability of risk assessment by various observer groups, including physicians and allied health professionals, commonly involved in the care of youth athletes. Fifteen athletes age 11-17 were filmed performing a drop vertical jump test. These videos were viewed by 242 observers including orthopaedic surgeons, orthopaedic residents/fellows, coaches, athletic trainers (ATCs), and physical therapists (PTs), with the observer asked to subjectively estimate the risk level of each jumper. Objective injury risk was calculated using normalized knee separation distance (measured using Dartfish, Alpharetta, GA), based on previously published studies. Risk assessments by observers were compared to each other to determine inter-rater reliability, and to the objectively calculated risk level to determine sensitivity and specificity. Seventy one observers repeated the test at a minimum of 6 weeks later to determine intra-rater reliability. RESULTS: Between groups, the inter-rater reliability was high, κ = 0.92 (95% CI 0.829-0.969, p < 0.05), indicating that no single group gave better (or worse) assessments, including comparisons between physicians and allied health professionals. With a screening cutoff isolated to subjects identified by observers as "high risk", the sensitivity was 63.06% and specificity 82.81%. Reducing the screening cutoff to also include jumpers identified as "medium risk" increased sensitivity to 95.04% and decreased the specificity to 46.07%. Intra-rater reliability was moderate, κ = 0.55 (95% CI 0.49-0.61, p < 0.05), indicating that individual observers made reproducible risk assessments. CONCLUSIONS: This study supports the use of a simple, field-based observational drop vertical jump screening test to identify athletes at risk for ACL injury. Our study shows good inter- and intra-rater reliability and high sensitivity and suggests that screening can be performed without significant training by physicians as well as allied health professionals, including: coaches, athletic trainers and physical therapists. Identification of these high-risk athletes may play a role in enrollment in appropriate preventative neuromuscular training programs, which have been shown to decrease the incidence of ACL injuries in this population.

Infrared assessment of knee instability in ACL deficient patients.

PURPOSE: Previous clinical studies have shown that anterior cruciate ligament (ACL) ruptures require reconstructive surgery. The main goal of this study is an objective test definition for unstable knee diagnosis based on real measurements by using infrared cameras and adequate software. METHODS: In the study of gait analysis 35 males with deficient ACL's participated. Pathological parameters for anterior posterior translation (APT) and internal external rotation (IER) and their values of kinematic data were obtained from a gait analysis 3D system. Movement curves were obtained by recording the position of fluorescent markers over time. A machine learning algorithm was developed in order to support decisions on the severity of the ACL injury and its corresponding deficiency. The algorithm was based on logistic regression. RESULTS: The value of APT, designated as exponentiation of the Ó¨ coefficient (Exp (Ó¨)) of APT, showed that the likelihood of ACL-deficient knee occurrence due to higher values of APT is 1.1758 (95 % CI) times more frequent than that of the patients with lower values of APT. The value of IER, designated as Exp (Ó¨) of IER, showed that the patients with higher values of IER present 2.2516 (95 % CI) times higher values of ACL-deficient knee frequency than those with lower values. CONCLUSION: This study showed that the creation of ordered pairs of pathological parameters gives a wider picture of ACL deficiency and that such an algorithm may improve both examination and treatment of patients.

[The value of 3 dimensional-fat suppression-spoiled gradient-recalled acquisition sequence on single compartment osteoarthritis for unicompartmental arthroplasty preoperative assessment].

OBJECTIVE: To analyze the 3 dimensional-fat suppression-spoiled gradient-recalled acquisition (3D-FS-SPGR) sequence in the diagnosis of knee articular cartilage injury. METHODS: A total of 56 knee osteoarthritis patients (26 males, 30 females, ages 52-73 years, mean 61.8 years) treated in Department of Orthopedics, Chinese People's Liberation Army General Hospital between June 2013 and May 2014 were involved in this study. All patients underwent knee MRI, plus 3D-FS-SPGR sequence, arthroscopic exploration, and in contrast to the results of MRI results analysis, evaluation 3D-FS-SPGR and conventional sequence of cartilage damage consistent with the arthroscopic accuracy. RESULTS: Divided 56 knee joints into 336 cartilage articular surface, included 55.1% normal articular surface, 21.4% early osteoarthritis and 23.5% advanced osteoarthritis. The accordance of 3D-FS-SPGR sequence grading and arthroscopic was 90.2%. The sensitivity of 3D-FS-SPGR sequence was 93.1%, specificity was 98.3%, and Kappa value was 0.849. The sensitivity of T2WI sequence was 84.4%, specificity was 96.9%, and the Kappa value was 0.671. CONCLUSION: For unicompartment osteoarthritis , MRI 3D-FS-SPGR sequence is effective in sensitivity and specificity of cartilage damage.

Diagnostic accuracy of the Thessaly test, standardised clinical history and other clinical examination tests (Apley's, McMurray's and joint line tenderness) for meniscal tears in comparison with magnetic resonance imaging diagnosis.

BACKGROUND: Reliable non-invasive diagnosis of meniscal tears is difficult. Magnetic resonance imaging (MRI) is often used but is expensive and incidental findings are problematic. There are a number of physical examination tests for the diagnosis of meniscal tears that are simple, cheap and non-invasive. OBJECTIVES: To determine the diagnostic accuracy of the Thessaly test and to determine if the Thessaly test (alone or in combination with other physical tests) can obviate the need for further investigation by MRI or arthroscopy for patients with a suspected meniscal tear. DESIGN: Single-centre prospective diagnostic accuracy study. SETTING: Although the study was performed in a secondary care setting, it was designed to replicate the results that would have been achieved in a primary care setting. PARTICIPANTS: Two cohorts of patients were recruited: patients with knee pathology (n = 292) and a control cohort with no knee pathology (n = 75). MAIN OUTCOME MEASURES: Sensitivity, specificity and diagnostic accuracy of the Thessaly test in determining the presence of meniscal tears. METHODS: Participants were assessed by both a primary care clinician and a musculoskeletal clinician. Both clinicians performed the Thessaly test, McMurray's test, Apley's test, joint line tenderness test and took a standardised clinical history from the patient. RESULTS: The Thessaly test had a sensitivity of 0.66, a specificity of 0.39 and a diagnostic accuracy of 54% when utilised by primary care clinicians. This compared with a sensitivity of 0.62, a specificity of 0.55 and diagnostic accuracy of 59% when used by musculoskeletal clinicians. The diagnostics accuracy of the other tests when used by primary care clinicians was 54% for McMurray's test, 53% for Apley's test, 54% for the joint line tenderness test and 55% for clinical history. For primary care clinicians, age and past history of osteoarthritis were both significant predictors of MRI diagnosis of meniscal tears. For musculoskeletal clinicians age and a positive diagnosis of meniscal tears on clinical history taking were significant predictors of MRI diagnosis. No physical tests were significant predictors of MRI diagnosis in our multivariate models. The specificity of MRI diagnosis was tested in subgroup of patients who went on to have a knee arthroscopy and was found to be low [0.53 (95% confidence interval 0.28 to 0.77)], although the sensitivity was 1.0. CONCLUSIONS: The Thessaly test was no better at diagnosing meniscal tears than other established physical tests. The sensitivity, specificity and diagnostic accuracy of all physical tests was too low to be of routine clinical value as an alternative to MRI. Caution needs to be exercised in the indiscriminate use of MRI scanning in the identification of meniscal tears in the diagnosis of the painful knee, due to the low specificity seen in the presence of concomitant knee pathology. Further research is required to determine the true diagnostic accuracy and cost-effectiveness of MRI for the detection of meniscal tears. TRIAL REGISTRATION: Current Controlled Trial ISRCTN43527822. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Risk assessment for anterior cruciate ligament injury.

INTRODUCTION: Anterior cruciate ligament tears are one of the most frequent soft tissue injuries of the knee. A torn anterior cruciate ligament leaves the knee joint unstable and at risk for further damage to other soft tissues manifested as pain, dislocation, and osteoarthritis. A better understanding of the anatomical details of knee joints suffering anterior cruciate ligament tears is needed to understand and develop prediction models for anterior cruciate ligament injury and/or tear. MATERIALS AND METHODS: Magnetic resonance images of 32 patients with anterior cruciate ligament tears and 40 patients with non-tears were evaluated from a physician group practice. Digital measurements of femoral condyle length, femoral notch width, anterior cruciate ligament width in the frontal and sagittal plane, and the anterior cruciate ligament length in the sagittal plane were taken in both groups to identify trends. Monte Carlo simulations were performed (n = 2000) to evaluate the relationship between notch width index and sagittal width and to establish functional relationships among the anatomical parameters for potential injury risk. Sensitivity analysis performed shows the risk of anterior cruciate ligament injury a function of force and notch width index. RESULTS: Females have a significantly shorter anterior cruciate ligament when compared to that of males. The notch width index was also significantly different between torn and non-torn individuals. The NWI was not significantly different between genders (p value = 0.40). CONCLUSIONS: Anterior cruciate ligament injury has been shown to be caused by the forces which act on the ligament. These forces can result from hyperextension of the tibia or the internal rotation of tibia. The anatomical parameters of the knee joint (i.e., notch width index, anterior cruciate ligament width and length) have no role in the cause of an injury.

Radiological assessment of irreducible posterolateral knee subluxation after dislocation due to interposition of the vastus medialis: a case report.

Knee dislocation is a serious and relatively uncommon traumatism that every emergency room is supposed to diagnose and treat rapidly. Most of the time these dislocations reduce spontaneously or with closed reduction. If a subluxation persists, an incarceration of soft tissue in the joint must be suspected. Irreducible knee subluxations after dislocation are rare entities better described in the orthopaedic than in the radiological literature. However, the initial radiological assessment is an important tool to obtain the correct diagnosis, to detect neurovascular complications, and to plan the most suitable treatment. In cases of delayed diagnosis, the functional prognosis of the joint and even the limb may be seriously compromised primarily because of vascular lesions. Thereby, vascular imaging is essential in cases of dislocation of the knee, and we will discuss the role of angiography and the more recent use of computed tomography angiography or magnetic resonance angiography. Our patient presented with an irreducible knee subluxation due to interposition of the vastus medialis, and we will review the classical clinical presentation and 'do not miss' imaging findings on conventional radiography, computed tomography angiography, and magnetic resonance imaging. Finally, we will also report the classical imaging pathway indicated in knee dislocation, with a special emphasis on the irreducible form.

Clinical Assessment Versus MRI Diagnosis of Meniscus Tears.

CLINICAL SCENARIO: Common injuries in high-level and recreational athletes, nonathletes, and the elderly are medial and lateral meniscus tears. Diagnosis of meniscus tears is done with clinical exam, magnetic resonance imaging (MRI), and arthroscopy. The gold standard is arthroscopy, but accuracy of a clinical exam versus MRI diagnosis of meniscus tears is in question. A clinician's ability to detect a meniscus tear is beneficial to the patient from a timing standpoint. The process of obtaining an MRI and results could be lengthy, but if the meniscus tear is accurately diagnosed clinically, the patient could be suspended from athletics or specific job duties to prevent further injury. In addition, rehabilitation could be initiated immediately, resulting in better outcomes for the patient. The ability to diagnose a meniscus tear clinically could initiate the rehabilitation process much sooner than waiting for MRI testing and results. Beginning the rehabilitation phase earlier may lead to faster postoperative rehabilitation and better patient outcomes. Clinical detection of a meniscus tear will facilitate possible suspension, early treatment, and rehabilitation recommendations, but the MRI will provide more specific information about the injury, including type and location of tear. Thus, surgical decisions such as operative versus nonoperative or meniscectomy versus repair would be based on MRI results. Focused Clinical Question: Is a clinical exam as accurate as an MRI scan for diagnosing meniscus tears?

Diagnostic performance of magnetic resonance imaging and pre-surgical evaluation in the assessment of traumatic intra-articular knee disorders in children and adolescents: what conditions still pose diagnostic challenges?

BACKGROUND: Diagnosis of intra-articular lesions in children based on clinical examination and MRI is particularly challenging. OBJECTIVE: To evaluate the diagnostic performance of MRI and pre-surgical evaluation of the knee in pediatric patients relative to arthroscopic evaluation as the gold standard. We report diagnoses frequently missed or inaccurately diagnosed pre-operatively. MATERIALS AND METHODS: We conducted a retrospective review of MRI and pre-surgical evaluation in children and adolescents ages 1-17 years who were treated by knee arthroscopy during a 2½-year period. All MRIs were reviewed by a pediatric radiologist blinded to clinical findings. Pediatric orthopedic clinic notes were reviewed for pre-surgical evaluation (based on physical exam, radiograph, MR images and radiologist's MRI report). Arthroscopic findings were used as the gold standard. We calculated the percentages of diagnoses at arthroscopy missed on both MRI and pre-surgical evaluation. Diagnostic accuracy between children and adolescents and in patients with one pathological lesion vs. those with >1 lesion was analyzed. We performed a second review of MR images of the missed or over-called MRI diagnoses with knowledge of arthroscopic findings. RESULTS: We included 178 children and adolescents. The most common diagnoses missed on MRI or pre-surgical evaluation but found at arthroscopy were: discoid meniscus (8/30, or 26.7% of cases); lateral meniscal tears (15/80, or 18.8% of cases); intra-articular loose bodies (5/36, or 13.9% of cases), and osteochondral injuries (9/73, or 12.3% of cases). Overall diagnostic accuracy of MRI and pre-surgical evaluation was 92.7% and 95.3%, respectively. No significant difference in diagnostic accuracy between children and adolescents was observed. When multiple intra-articular lesions were present, lateral meniscal tears were more likely to be inaccurately diagnosed (missed or over-called) on both MRI (P = 0.009) and pre-surgical evaluation (P < 0.001). CONCLUSION: Overall diagnostic accuracy of MRI and pre-surgical evaluation was quite high. The traumatic intra-articular knee lesions that still pose a diagnostic challenge for MRI and pre-surgical evaluation are lateral discoid meniscus, lateral meniscal tears, intra-articular loose bodies and osteochondral injuries. Special attention should be given to those diagnoses when evaluating a pediatric knee MRI. In children with multiple intra-articular injuries, there is significantly more inaccuracy in pre-arthroscopic diagnosis of lateral meniscal tears on both MRI and pre-surgical evaluation.

Quantitative pivot shift assessment using combined inertial and magnetic sensing.

PURPOSE: The purpose of the study was to demonstrate the feasibility of a new measurement system using micro-electromechanical systems (MEMS)-based sensors for quantifying the pivot shift phenomenon. METHODS: The pivot shift test was performed on 13 consecutive anterior cruciate ligament-deficient subjects by an experienced examiner while femur and tibia kinematics were recorded using two inertial sensors each composed of an accelerometer, gyroscope and magnetometer. The gravitational component of the acquired data was removed using a novel method for estimating sensor orientations. Correlation between the clinical pivot shift grade and acceleration and velocity parameters was measured using Spearman's rank correlation coefficients. RESULTS: The pivot shift phenomenon was best characterized as a drop in femoral acceleration observed at the time of reduction. The correlation between the femoral acceleration drop and the clinical grade was shown to be very strong (r = 0.84, p < 0.0001). CONCLUSIONS: The present study demonstrates the feasibility of quantifying the pivot shift using MEMS-based sensors and removing the gravitational component of acceleration using an estimation of sensor orientation for improved correlation to the clinical grade.

Assessment and treatment of knee pain in the child and adolescent athlete.

Knee pain in children and adolescents is one of the most prevalent complaints in a pediatric practice, accounting for at least a third of musculoskeletal complaints. Accurate diagnosis requires an understanding of knee anatomy and patterns of knee injuries and skill in physical examination. This review covers the most common causes of knee pain in children and adolescents, including overuse issues, such as Osgood-Schlatter and osteochondritis dissecans, as well as traumatic injuries, including tibial spine fractures and anterior cruciate ligament injuries.