Clinical, MRI, and arthroscopic correlation in meniscal and anterior cruciate ligament injuries

Risk factors for false positive and false negative MRI in diagnosing medial and lateral meniscal tears with concomitant ACL injury

OBJECTIVE

To determine the diagnostic performance of MRI in evaluating meniscal abnormalities in the setting of anterior cruciate ligament (ACL) injury and recognize predictors of false positive (FP) and false negative (FN) MRI diagnosis.

MATERIAL AND METHODS

Four hundred twenty patients (mean age, 27.2 years; 326 males, 94 females) who underwent arthroscopy for ACL injury between January 2017 and August 2022, and had preoperative imaging within 4 months, were retrospectively included. Images were independently interpreted by two experienced musculoskeletal radiologists, noting the presence of medial and lateral meniscal tears including tear type and location. Results were correlated with arthroscopic findings. Multivariate logistic regression was implemented to study risk factors (RF) for FP and FN MRI diagnosis.

RESULTS

The sensitivity/specificity/positive predictive value/negative predictive value/accuracy of MRI for medial meniscus tear was 97.5%/74.46%/65.63%/98.35%/82.15%; for lateral meniscus tear, it was 83.5%/93.70%/70.8%/94.55% /87.86%, with substantial interreader agreement. Female gender (odds ratio (OR), 0.434), posterior horn and posterior root tears (OR, 3.268/22.588), horizontal tear (OR, 3.134), and ramp lesion (OR, 4.964) were found RF for FP medial meniscus, and meniscal body tears (OR, 308.011) were found RF for FP lateral meniscus. RF for FN medial meniscus were meniscal tear at the posterior horn, body, and posterior root (OR, 12.371/123.000/13.045).

CONCLUSION

MRI is an effective screening tool for meniscal tears, but less accurate in detecting all medial meniscus injuries. Gender, meniscal tear location, and type increased the risk of FP medial meniscal tear on MRI, while meniscal tear location increased the risk of FP lateral meniscus and FN medial meniscus tears.

Anterior Cruciate Ligament Tear: Individualized Indications for Non-Operative Management

Anterior cruciate ligament (ACL) rupture represents a common sports injury that is mostly managed operatively. However, non-operative treatment can also play a role, despite the limited high-quality published data on ACL tear management. Both methods have shown favorable outcomes, but clear guidelines based on high-quality research are lacking. Several factors should be considered and discussed with the patient before deciding on the best treatment method. These include patient characteristics and expectations, concomitant injuries, and clinical evaluation, with laxity or/and instability being one of the most essential parameters examined. This should eventually lead to an individualized approach for each patient to ensure the best possible outcome. This review aims to delve into all parameters that are related to ACL rupture and guide physicians in choosing the most appropriate treatment method for each patient.

Comparison of Clinical, Magnetic Resonance Imaging (MRI) and Arthroscopic Findings in Assessment of Cartilage Defects and Internal Derangement of Knee

BACKGROUND

The knee is the most commonly injured joint because of its anatomical structure, its exposure to external forces, and its functional demands. Orthopaedic surgeons previously relied on clinical evaluation for diagnosing any internal derangement of the knee joint. With the advent of new clinical methods for diagnosing ligament injuries and cartilage defects, there are very less studies comparing the accuracy of all three methods, clinical examination, magnetic resonance imaging (MRI) and arthroscopy to reach a definitive diagnosis.

OBJECTIVE

This study aims to compare the sensitivity, specificity, accuracy and predictive values of clinical examination and MRI with that of arthroscopy which is the ideal investigation of choice for cartilage defects and internal derangements of the knee.

MATERIAL AND METHODS

A prospective, observational and hospital-based study was done on patients with internal derangement of knee and cartilage defects. Clinical examination (based on the clinical tests for each ligament), MRI (1.5 T) and arthroscopy were done on all patients, the findings of which were compared using the Chi-square test. The following parameters were assessed while using arthroscopy as the gold standard of reference: accuracy, specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Anterior cruciate ligament (ACL) was the most common ligament to be injured followed by the medial meniscus. The overall accuracy of clinical evaluation and MRI to diagnose meniscal injuries was found to be 94% and 91% respectively. The clinical examination had sensitivity and specificity of 96% and 82% in diagnosing ACL tears, respectively, whereas MRI had sensitivity and specificity of 88% and 76% respectively. For the medial meniscus, the clinical examination had sensitivity and specificity of 93% and 96% respectively whereas MRI had a sensitivity of 100% and specificity of 89%. We observed that the accuracy of MRI for grading ACL and meniscal tears was similar i.e. 79% and 78% respectively, but was slightly low (70%) for grading of chondromalacia patellae.

CONCLUSION

This study supports the use of MRI and clinical assessment in the diagnosis of chondral defects and internal knee derangement. Clinical tests are reliable and have high sensitivity in diagnosing ACL tears and chondral defects when compared to MRI. Not all lesions should routinely undergo MRI for diagnostic purposes; only a few circumstances warrant its usage. MRI is less reliable in grading ACL tears, meniscal tears and chondral injuries.

American Academy of Orthopaedic Surgeons Clinical Practice Guideline Case Study: Management of Anterior Cruciate Ligament Injuries

Considering the frequency of anterior cruciate ligament (ACL) tears, optimal management of these injuries was the subject of a 2022 clinical practice guideline update from The American Academy of Orthopaedic Surgeons (AAOS) with input from representatives from the American Orthopaedic Society for Sports Medicine, the Pediatric Orthopaedic Society of North America, the American Orthopaedic Society for Sports Medicine, the American Medical Society for Sports Medicine, the American Academy of Physical Medicine and Rehabilitation, and the American College of Emergency Physicians. The eight recommendations and seven options to guide orthopaedic surgeons and other physicians managing patients with these anterior cruciate ligament injuries are based on the best current available evidence. The cases presented in this article are examples designed to demonstrate the clinical application of these guidelines.

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.

A longer duration from injury to surgery is associated with preoperative deterioration of an isolated meniscal tear in patients aged 40 years or older

PURPOSE

To evaluate the preoperative deterioration of an isolated meniscal tear in patients aged 40 years or older, and whether time from injury to surgery is associated with worsening of a meniscal tear.

METHODS

Patients aged 40 years or older who underwent arthroscopic surgery for isolated meniscal tear between 2014 and 2019 were retrospectively reviewed. The diagnostic magnetic resonance imaging (MRI) findings and arthroscopic findings were compared to evaluate the deterioration of meniscal tears. Predictors of the development of meniscal tears; patient demographic factors, duration from injury to surgery (injury to MRI and MRI to surgery), and image findings were assessed.

RESULTS

A total of 58 patients (58 knees) were included (mean age, 55.9 ± 8.5 years; male/female, 31/27). An isolated meniscal tear deteriorated in 28 (48.3%). Compared patients with and without deteriorated meniscal tear, significant differences were found in the MRI grade of meniscal tear (p = 0.03), duration from injury to MRI (164.2 ± 167.9 vs 45.2 ± 48.7 days, p < 0.001), and from MRI to surgery (148.8 ± 91.1 vs 67.6 ± 56.7 days, p < 0.001). A multivariate regression analysis showed that the duration from injury to MRI (odds ratio [OR], 1.03; p < 0.001) and from MRI to surgery (OR, 1.02; p < 0.001) were independent predictors.

CONCLUSION

Approximately 50% of isolated meniscal tears deteriorated preoperatively in patients aged 40 years or older. The duration from injury to surgery was an independent predictor of worsening of an isolated meniscal tear.

Treatment of Combined Injuries to the ACL and the MCL Complex: A Consensus Statement of the Ligament Injury Committee of the German Knee Society (DKG)

Background:

Different indications and treatment options for combined injuries to the anterior cruciate ligament (ACL) and medial collateral ligament complex (MCL) are not clearly defined.

Purpose:

To perform a modified Delphi process with the Committee for Ligament Injuries of the German Knee Society (DKG) in order to structure and optimize the process of treating a combined injury to the ACL and MCL.

Study Design:

Consensus statement.

Methods:

Scientific questions and answers were created based on a comprehensive literature review using the central registers for controlled studies of Medline, Scopus, and Cochrane including the terms medial collateral ligament, anterior cruciate ligament, MCL, ACL, and outcome used in various combinations. The obtained statements passed 3 cycles of a modified Delphi process during which each was readjusted and rated according to the available evidence (grades A-E) by the members of the DKG Ligament Injuries Committee and its registered guests.

Results:

The majority of answers, including several questions with >1 graded answer, were evaluated as grade E (n = 16) or C (n = 10), indicating that a low level of scientific evidence was available for most of the answers. Only 5 answers were graded better than C: 3 answers with a grade of A and 2 answers with a grade of B. Only 1 answer was evaluated as grade D. An agreement of >80% (range, 83%-100%) among committee members was achieved for all statements.

Conclusion:

The results of this modified Delphi process offer a guideline for standardized patient care in cases of combined injuries to the ACL and MCL.

Correlation between Magnetic Resonance Imaging and Arthroscopic Findings in Knee Lesions

Background: Magnetic resonance imaging (MRI) is a noninvasive diagnostic method with no known side effects and a high sensitivity for detecting meniscal lesions as well as lesions of the anterior and posterior cruciate ligaments. For a correct and complete diagnosis, MRI results must be interpreted in the context of clinical examination and anamnesis. MRI results can support the surgical indication for arthroscopy, which is a minimally invasive intervention that facilitates the visualization, investigation, diagnosis, and treatment of intra-articular lesions of the knee. The purpose of this study was to assess the correlation between MRI results and the intra-articular lesions detected arthroscopically.

Material and methods: This retrospective study evaluated a total of 60 patients admitted and treated between January 1, 2013 and January 1, 2014 in the Clinic of Orthopedics and Traumatology of Mureș County Hospital, Târgu Mureș, Romania.

Results: In the 43 patients with lesion of the anterior cruciate ligament, the lesions were seen on MRI in 40 patients (93%) and confirmed arthroscopically in 37 patients (86%). In 34 cases (79.1% of the total of 43), the MRI and arthroscopic results were similar, the Kappa coefficient showing a high degree of correlation (0.90).

Conclusion: By assessing the Kappa coefficient to highlight the correlation between MRI results and arthroscopic diagnosis for knee injuries, a statistically relevant correlation between the two methods was found. This suggests that a correct diagnosis can be achieved by both methods.

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.

Descriptive study of knee lesions using magnetic resonance imaging and correlation between medical imaging diagnosis and suspected clinical diagnosis

Objective:

This study aimed to assess the meniscus and cruciate ligament lesions of the knee using magnetic resonance imaging (MRI) and to investigate the correlation between clinical and MRI diagnoses.

Patients and Methods:

Herein, we reviewed the electronic medical records of 240 patients who underwent knee MRI. The images were evaluated and then the clinical and MRI diagnoses were compared.

Results:

Of the 240 patients, 66% were male and the mean age was 40.6 ± 15.5 years (range, 2-79 years). Knee pain alone was the most common presenting symptom (50.64%) followed by pain after trauma (47.92%). Majority of the knee lesions were medial meniscus (MM) lesions (63%) followed by osteoarthritis (48%) and ACL lesions (35%). The majority of the MM and ACL lesions were tears (54.6% and 69.41%, respectively) followed by degeneration (33.55% and 17.65%, respectively). However, the MM lesions were predominantly observed in the posterior horn (Odds ratio [OR], 152; 95% confidence interval (CI), 21.550–1072.113; P < 0.001). The ACL lesions were significantly more common in men than in women (OR, 0.355; 95% CI, 0.191-0.661; P = 0.001), and altered signal intensity on T2- and proton density–weighted images was the most common sign (P < 0.001). A strong compatibility was observed between the clinical and MRI diagnoses (Kappa = 0.141; P < 0.001).

Conclusion:

MM and ACL lesions are the most common injuries of the knee, which can be diagnosed by physical examination in most cases. Further confirmation by MRI should be reserved for doubtful cases only.

Towards improving the identification of anterior cruciate ligament tears in primary point-of-care settings

Background

Only a small proportion of anterior cruciate ligament (ACL) tears are diagnosed on initial healthcare consultation. Current clinical guidelines do not acknowledge that primary point-of-care practitioners rely more heavily on a clinical history than special clinical tests for diagnosis of an ACL tear. This research will assess the accuracy of combinations of patient-reported variables alone, and in combination with clinician-generated variables to identify an ACL tear as a preliminary step to designing a primary point-of-care clinical decision support tool.

Methods

Electronic medical records (EMRs) of individuals aged 15–45 years, with ICD-9 codes corresponding to a knee condition, and confirmed (ACL⁺) or denied (ACL⁻) first-time ACL tear seen at a University-based Clinic between 2014 and 2016 were eligible for inclusion. Demographics, relevant diagnostic indicators and ACL status based on orthopaedic surgeon assessment and/or MRI reports were manually extracted. Descriptive statistics calculated for all variables by ACL status. Univariate between group comparisons, clinician surveys (n = 17), availability of data and univariable logistic regression (95%CI) were used to select variables for inclusion into multivariable logistic regression models that assessed the odds (95%CI) of an ACL-tear based on patient-reported variables alone (consistent with primary point-of-care practice), or in combination with clinician-generated variables. Model performance was assessed by accuracy, sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (95%CI).

Results

Of 1512 potentially relevant EMRs, 725 were included. Participant median age was 26 years (range 15–45), 48% were female and 60% had an ACL tear. A combination of patient-reported (age, sport-related injury, immediate swelling, family history of ACL tear) and clinician-generated (Lachman test result) variables were superior for ACL tear diagnosis [accuracy; 0.95 (90,98), sensitivity; 0.97 (0.88,0.98), specificity; 0.95 (0.82,0.99)] compared to the patient-reported variables alone [accuracy; 84% (77,89), sensitivity; 0.60 (0.44,0.74), specificity; 0.95 (0.89,0.98)].

Conclusions

A high proportion of individuals without an ACL tear can be accurately identified by considering patient-reported age, injury setting, immediate swelling and family history of ACL tear. These findings directly inform the development of a clinical decision support tool to facilitate timely and accurate ACL tear diagnosis in primary care settings.

Management of traumatic meniscus tears: the 2019 ESSKA meniscus consensus

PURPOSE

The importance of meniscus integrity in the prevention of early osteoarthritis is well known, and preservation is accepted as the primary goal. The purpose of the ESSKA (European Society for Sports Traumatology, Knee Surgery and Arthroscopy) European consensus on traumatic meniscus tears was to provide recommendations for the treatment of meniscus tears based on both scientific evidence and the clinical experience of knee experts.

METHODS

Three groups of surgeons and scientists elaborated and ratified the so-called formal consensus process to define the recommendations for the management of traumatic meniscus tears. A traumatic meniscus tear was defined as a tear with an acute onset of symptoms caused by a sufficient trauma. The expert groups included a steering group of eight European surgeons and scientists, a rating group of another nineteen European surgeons, and a peer review group. The steering group prepared twenty-seven question and answer sets based on the scientific literature. The quality of the answers received grades of A (a high level of scientific support), B (scientific presumption), C (a low level of scientific support) or D (expert opinion). These question and answer sets were then submitted to and evaluated by the rating group. All answers were scored from 1 (= totally inappropriate) to 9 (= totally appropriate) points. Thereafter, the comments of the members of the rating group were incorporated by the steering group and the consensus was submitted to the rating group a second time. Once a general consensus was reached between the steering and rating groups, the finalized question and answer sets were submitted for final review by the peer review group composed of representatives of the ESSKA-affiliated national societies. Eighteen representatives replied.

RESULTS

The review of the literature revealed a rather low scientific quality of studies examining the treatment of traumatic meniscus tears. Of the 27 questions, only one question received a grade of A (a high level of scientific support), and another received a grade of B (scientific presumption). The remaining questions received grades of C and D. The mean rating of all questions by the rating group was 8.2 (95% confidence interval 8.1-8.4). A general agreement that MRI should be performed on a systematic basis was not achieved. However, MRI was recommended when arthroscopy would be considered to identify concomitant pathologies. In this case, the indication for MRI should be determined by a musculoskeletal specialist. Based on our data, stable left in situ lateral meniscus tears appear to show a better prognosis than medial tears. When repair is required, surgery should be performed as early as possible. Evidence that biological enhancement such as needling or the application of platelet-rich plasma would improve healing was not identified. Preservation of the meniscus should be considered as the first line of treatment because of an inferior clinical and radiological long-term outcome after partial meniscectomy compared to meniscus repair.

DISCUSSION

The consensus was generated to present the best possible recommendations for the treatment of traumatic meniscus tears and provides some groundwork for a clinical decision-making process regarding the treatment of meniscus tears. Preservation of the meniscus should be the first line of treatment when possible, because the clinical and radiological long-term outcomes are worse after partial meniscectomy than after meniscus preservation. The consensus clearly states that numerous meniscus tears that were considered irreparable should be repaired, e.g., older tears, tears in obese patients, long tears, etc. LEVEL OF EVIDENCE: II.

The accuracy of magnetic resonance imaging diagnosis of non-osseous knee injury at Steve Biko Academic Hospital

Background

Preoperative magnetic resonance imaging (MRI) has internationally been proven to reduce unnecessary knee arthroscopies and assist with surgical planning. This has the advantage of avoiding unnecessary surgery and the associated anaesthetic risk, as well as reducing costs. No data were found in the recently published literature assessing the accuracy of MRI interpretation of knee ligament injury in the public sector locally.

Objectives

This pilot study aimed to determine the accuracy of MRI in detecting non-osseous knee injury in a resource-limited tertiary-level academic hospital in Pretoria, South Africa, compared to the gold standard arthroscopy findings.

Method

This was an exploratory retrospective analysis of 39 patients who had MRI and arthroscopy at Steve Biko Academic Hospital (SBAH). True positive, true negative, false positive and false negative results were extrapolated from findings in both modalities and translated into sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each structure.

Results

Negative predictive values were recorded as 97%, 81%, 90% and 100% (anterior cruciate ligament [ACL], medial meniscus [MM], lateral meniscus [LM] and posterior cruciate ligament [PCL], respectively), which were comparative to recently published international literature. The PPV results were lower than those previously evaluated at 55%, 58%, 55% and not applicable. The sensitivities and specificities of the ligaments were 83%, 58%, 83% and not applicable; and 87%, 81%, 70% and not applicable, respectively.

Conclusion

Magnetic resonance imaging was found to be sensitive and specific, with a high NPV noted in all structures evaluated. Negative results can therefore be used to avoid unnecessary surgery to the benefit of the patient and state. The study reiterates that high accuracy can be obtained from MRI on a 1.5-tesla non-dedicated scanner, with interpretation by generalist radiologists.

Delayed reconstruction and high BMI z score increase the risk of meniscal tear in paediatric and adolescent anterior cruciate ligament injury

PURPOSE

The purpose of this study was to identify epidemiologic risk factors for secondary meniscal tears in paediatric and adolescent patients who sustain an anterior cruciate ligament (ACL) tear. The hypothesis was that delayed reconstruction and elevated BMI z score, increase the risk for secondary meniscal tears.

METHODS

A prospective, descriptive and analytical study of consecutively accrued children and adolescents with an ACL tear was performed. One hundred and sixty subjects (114 males and 46 females) were identified between 2006 and 2015 at one institution. The age range was between 7 and 19 years. Fifteen parameters were recorded and analysed: age at initial trauma, initial trauma circumstance, sex, BMI z score, affected side, type of sport, Tegner score, athletic level, time to MRI, time to first referral, time to surgery, age at surgery, attempted non-operative treatment, operative report and associated meniscal tear. These meniscal lesions could be diagnosed by an MRI and / or during surgery.

RESULTS

Out of the 160 cases, 143 were treated surgically and 17 cases non-operatively. Median corrected BMI z score was 0.5 (range - 1.8 to 4.7). 41.9% had one or more meniscal lesions. 55 patients were initially treated non-operatively, of which 39 patients were secondarily operated. There was a positive relationship between meniscal lesion and: BMI z score (p = 0.0364), attempted non-operative treatment (p = 0.001) and time to surgery (p = 0.002). The median time to ACL reconstruction was 229 days for patients with secondary meniscal lesions.

CONCLUSIONS

Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management. There was a positive correlation between BMI z score and secondary meniscal lesions. Thus, early ACL reconstruction is advocated in young athletes.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

Reliability assessment of a mechanism-based approach to post-injury knee magnetic resonance imaging interpretation by general radiologists

Background

A mechanism-based approach to post-injury knee magnetic resonance imaging (MRI) interpretation, following acute complex knee injury, is cited by several authors to provide increased reporting accuracy and efficiency, by allowing accurate prediction of injury to at-risk structures. This remains to our knowledge untested in a developing world setting and is of interest to us as South African general radiologists.

Objective

To assess the reliability of a mechanism-based approach to complex post-trauma knee MRI interpretation when implemented by general radiologists in a South African setting, and compare our results with the findings of North American authors who compiled and assessed the same classification. To measure the agreement between the observers.

Methods

A quantitative, observational, investigative, retrospective study was performed using a sample of 50 post-trauma knee MRI studies conducted at Grey's Hospital, Pietermaritzburg. Two investigators independently applied the consolidated mechanism-based approach compiled by Hayes et al. as a research tool to interpret the knee MRI studies, blinded to each other's findings.

Results

Injury mechanism was assigned in 32% of cases by the principle investigator and in 20% of cases by the supervisor, with fair agreement between the observers (k = 0.39). The investigators agreed that 62% of cases were not classifiable by mechanism, 26% because of highly complex injury and 26% because of non-specific findings.

Conclusion

Our findings indicate that the Hayes et al. classification is a non-ideal tool when used by general radiologists in our setting, as the pure injury mechanisms described in the classification were rare in our study group. Patient epidemiology and investigator experience are highlighted as potential limiting factors in this study. Despite this, we advocate that the concept of a mechanism-based approach for the interpretation of acute post-trauma knee MRI holds value for general radiologists, particularly in patients imaged before resolution of bone bruising (within 12-16 weeks of injury), and those injured in sporting and similar athletic activities.

Variations in the attachments of the medial meniscal anterior horn: a descriptive cadaveric study

PURPOSE

Meniscal tears are common in Kenya, with prevalence rates ranging from 45 to 78% of intracapsular knee pathology. Diagnosis of these injuries relies on the use of both clinical signs and symptoms as well as radiological investigations. In a few instances, radiological detection could be difficult, partly because of variant attachment patterns of the medial meniscal anterior horn. Some of these unusual attachments of the anterior horn of the medial meniscus could even be mistaken for meniscal tears. There is also evidence that these variations differ from population to population. This study, therefore, aimed to determine the variant bony and ligamentous attachments of the medial meniscal anterior horn in a sample Kenyan population.

METHODS

The study was conducted at the Department of Human Anatomy, University of Nairobi. Thirty-one male and female unpaired medial menisci were obtained from cadaveric specimen. The bony and ligamentous attachments were identified and recorded and photomacrographs taken.

RESULTS

The bony attachments different from the classical textbook attachment accounted for 54.8% of the medial meniscal anterior horns. The anterior intermeniscal ligament was present in 62.3% while 16.2% showed attachment to the anterior cruciate ligament. Twenty-nine percent (29%) of the medial menisci studied did not have any ligamentous attachments.

CONCLUSIONS

The bony and ligamentous attachments of the medial meniscal anterior horn are highly variable presenting unique diagnostic and therapeutic challenges. A new classification of ligamentous attachments is thus proposed.

Use of MRI by radiologists and orthopaedic surgeons to detect intra-articular injuries of the knee

OBJECTIVE

Magnetic resonance imaging (MRI) is paramount in the assessment of knee pathology, particularly when planning for a surgical procedure. This study compared the diagnostic accuracy in MRI reading of pathological knees by radiologists and orthopaedic surgeons.

MATERIALS AND METHODS

Cross-sectional study comprising 80 randomly selected patients previously submitted to arthroscopic surgery after clinical examination and MRI. A diagnosis by MRI interpretation was requested from the two teams, one of radiologists and another of orthopaedic surgeons. The conclusions of each team were later compared. Statistical significance was considered for p < 0.05.

RESULTS

The radiologists' findings achieved statistical significance regarding osteochondral injuries, ACL, and medial meniscus (p < 0.05), and orthopaedic surgeons regarding ACL injuries and menisci (p < 0.05). ACL injuries demonstrated a statistically significant association between teams (p < 0.001).

CONCLUSIONS

MRI appears to offer reliable readings of ACL injuries, regardless the specialty of the observer. The lateral compartment is scarcely well read.

The diagnostic accuracy of magnetic resonance imaging for anterior cruciate ligament injury in comparison to arthroscopy: a meta-analysis

We performed this meta-analysis to examine the diagnostic accuracy of MRI for the diagnosis of anterior cruciate ligament (ACL) injury in comparison to arthroscopy. We also compared the diagnostic accuracy of MRI with magnetic field intensities (MFI) greater than or equal to 1.5T with those below 1.5T, in addition to different MRI sequences. Studies relevant to the diagnosis of ACL injury by MRI and arthroscopy were analyzed. Computer and manual retrieval were carried out on studies published between January 1, 2006 and May 31, 2016. Twenty-one papers were included. Neither threshold nor non-threshold effects were present (p = 0.40, p = 0.06). The pooled sensitivity (SE), specificity (SP), positive likelihood ratio (LR+), negative likelihood ratio (LR−) and diagnostic odds ratio (DOR) with 95% confidence interval (CI) were 87% (84–90%), 90% (88–92%), 6.78 (4.87–9.44), 0.16 (0.13–0.20) and 44.70 (32.34–61.79), respectively. The area under the curve (AUC) was 0.93. The risk of publication bias was negligible (p = 0.75). In conclusion, examination by MRI is able to provide appreciable diagnostic performance. However, the principle, which states that the higher the MFI, the better the diagnostic accuracy, could not be verified. Additionally, conventional sequences (CSs) associated with proton density-weighted imaging (PDWI) are only slightly better than CSs alone, but not statistically different.

Physical Examination of the Knee: Meniscus, Cartilage, and Patellofemoral Conditions

The knee is one of the most commonly injured joints in the body. Its superficial anatomy enables diagnosis of the injury through a thorough history and physical examination. Examination techniques for the knee described decades ago are still useful, as are more recently developed tests. Proper use of these techniques requires understanding of the anatomy and biomechanical principles of the knee as well as the pathophysiology of the injuries, including tears to the menisci and extensor mechanism, patellofemoral conditions, and osteochondritis dissecans. Nevertheless, the clinical validity and accuracy of the diagnostic tests vary. Advanced imaging studies may be useful adjuncts.

Cartilage Delamination Flap Mimicking a Torn Medial Meniscus

We report a case of a chondral delamination lesion due to medial parapatellar plica friction syndrome involving the medial femoral condyle. This mimicked a torn medial meniscus in clinical and radiological presentation. Arthroscopy revealed a chondral delamination flap, which was debrided. Diagnosis of chondral lesions in the knee can be challenging. Clinical examination and MRI have good accuracy for diagnosis and should be used in tandem. Early diagnosis and treatment of chondral lesions are important to prevent progression to early osteoarthritis.

Comparison of clinical, MRI and arthroscopic assessments of chronic ACL injuries, meniscal tears and cartilage defects

PURPOSE

The aim of this study was to compare the accuracy of clinical examination to that of MRI evaluated by two independent radiologists for the diagnosis of meniscal tears and chronic anterior cruciate ligament injuries and to assess the MRI accuracy in the diagnosis of cartilage defects.

METHODS

Seventy-six consecutive patients with suspected intra-articular knee pathology were prospectively evaluated by objective examination, 1.5 T MRI, re-examined by trained radiologist and arthroscopy. Accuracy, sensitivity, specificity, positive predictive value and negative predictive value were calculated. Agreement analysis with kappa (К) coefficient values was performed for meniscal and ACL tears.

RESULTS

No differences were found between diagnostic accuracy of clinical examination, the first and second MRI reports in diagnosis of medial meniscus (84 vs 96 vs 97 %) and anterior cruciate ligament injuries (93 vs 78 vs 89 %). For the lateral meniscal tears, the accuracy of the second radiologist was significantly higher than those of the first (96 vs 75 %; p < 0.01) and clinical examination (96 vs 86 %; p = 0.02). High diagnostic values were obtained for the diagnosis of full-thickness chondral defects with sensitivity of 100 %, specificity of 95 % and accuracy of 95 %.

CONCLUSION

Clinical and MRI evaluations have no differences in the diagnosis of medial meniscus and anterior cruciate ligament injuries. A trained radiologist obtained better sensitivity, specificity and accuracy in the diagnosis of lateral meniscus. 1.5 T MRI does not represent the technique of choice in the evaluation of chondral defect but demonstrated high diagnostic accuracy for detection of full-thickness chondral defects.

LEVEL OF EVIDENCE

Diagnostic prospective study, Level II.

Where does magnetic resonance imaging stand in the diagnosis of knee injuries?

BACKGROUND

The aim of this study was to determine the diagnostic value of magnetic resonance imaging (MRI) in the diagnosis of knee injuries.

MATERIALS AND METHODS

Ninety-eight consecutive patients were enrolled in the study. In all patients, MRI and arthroscopy were performed and the results were compared.

RESULTS

MRI was most sensitive in the detection of medial meniscus injuries, and the highest specificity and negative predictive value (NPV) were found in the detection of posterior cruciate ligament injuries.

CONCLUSION

MRI is a valuable tool, and according to its high NPV, normal MRI can prevent unnecessary arthroscopic interventions.

Accuracy of MRI evaluation of meniscus tears in the setting of ACL injuries

BACKGROUND

Our purpose was to evaluate the diagnostic performance of magnetic resonance imaging (MRI) for the pre-operative detection of meniscus tears requiring operative intervention, and identify factors that determined accuracy of diagnosing meniscus tears, in the setting of anterior cruciate ligament (ACL) reconstruction.

METHODS

Patients who underwent primary ACL reconstruction were retrospectively reviewed. A meniscus tear was classified as requiring treatment if it was debrided or repaired at the time of ACL reconstruction. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of pre-operative MRIs were determined for medial and lateral meniscus tears.

RESULTS

Sensitivity, specificity, PPV, and NPV of MRI were 0.90, 0.75, 0.58, and 0.95 for medial meniscus tears, respectively, and 0.67, 0.81, 0.65, and 0.82 for lateral meniscus tears. MRI-diagnosed medial meniscus tears were associated with a longer time interval between initial injury and imaging compared to ACL tears without concomitant meniscus injury on MRI (p=0.038). Vertical medial meniscus tears were less likely than other tear patterns to require treatment at the time of ACL reconstruction (p=0.03). MRI showed a higher diagnostic performance for lateral meniscus tears when surgery was performed within 30days of imaging.

CONCLUSIONS

This study demonstrates only moderate sensitivity and specificity of pre-operative MRI in the detection of meniscus tears requiring operative treatment in the setting of ACL injury. High rates of false diagnoses were observed, suggesting MRI may not be as accurate in predicting positive or negative meniscus findings at the time of ACL reconstruction as previously reported.

LEVEL OF EVIDENCE

Level III.

Objective measurements of static anterior and rotational knee laxity

Several devices allow to measure anterior and rotational static knee laxity. To date, the use of rotational laxity measurements in the daily clinical practice however remains to be improved. These measurements may be systematically integrated to the follow-up of knee injuries. Physiologic laxity measurements may particularly be of interest for the identification of risk factors in athletes. Furthermore, knee laxity measurements help to improve the diagnosis of knee soft tissue injuries and to follow up reconstructions. Further prospective follow-ups of knee laxity in the injured/reconstructed knees are however required to conclude on the best treatment strategy for knee soft tissue injuries.

Diagnostic Efficacy of 3-T MRI for Knee Injuries Using Arthroscopy as a Reference Standard: A Meta-Analysis

OBJECTIVE

The objectives of our study were to assess the evidence for the diagnostic efficacy of 3-T MRI for meniscal and anterior cruciate ligament (ACL) injuries in the knee using arthroscopy as the reference standard and to compare these results with the results of a previous meta-analysis assessing 1.5-T MRI.

MATERIALS AND METHODS

The online Cochrane Library, MEDLINE, and PubMed databases were searched using the following terms: MRI AND ((3 OR three) AND (Tesla OR T)) AND knee AND arthroscopy AND (menisc* OR ligament). Patient demographics, patient characteristics, MRI scanning details, and diagnostic results were investigated. The methodologic quality of the included studies was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. A meta-analysis of studies using 3-T MRI was performed, and the results were compared with a previous meta-analysis of studies using 1.5-T MRI.

RESULTS

One hundred one studies were identified by the search strategy, and 13 studies were included in our review. Twelve studies were considered to have level 1b evidence, and one study was considered to have level 2b evidence. All 13 studies had high methodologic integrity and low risk of bias using the QUADAS-2 tool. The studies included 1197 patients with a mean age of 41.9 years. Ten of the 13 studies were eligible for meta-analysis. The mean sensitivity and mean specificity of 3-T MRI for knee injuries by location were as follows: medial meniscus, 0.94 (95% CI, 0.91-0.96) and 0.79 (95% CI, 0.75-0.83), respectively; lateral meniscus, 0.81 (95% CI, 0.75-0.85) and 0.87 (95% CI, 0.84-0.89); and ACL, 0.92 (95% CI, 0.83-0.96) and 0.99 (95% CI, 0.96-1.00). The specificity of 3-T MRI for injuries of the lateral meniscus was significantly lower than that of 1.5-T MRI (p = 0.0013).

CONCLUSION

This study does not provide evidence that 3-T scanners have superior diagnostic efficacy for meniscal damage and ACL integrity when compared with previous studies of 1.5-T machines.

Risk Factors of False-Negative Magnetic Resonance Imaging Diagnosis for Meniscal Tear Associated With Anterior Cruciate Ligament Tear

PURPOSE

To identify risk factors that predict false-negative magnetic resonance imaging (MRI) diagnosis for meniscal tear coincident with anterior cruciate ligament injury using multivariate logistic regression.

METHODS

We reviewed the medical records of consecutive patients who underwent arthroscopic anterior cruciate ligament reconstruction from January 2006 through December 2014. Exclusion criteria were no meniscal tear or incomplete tear less than 10 mm in length, delay to surgery from initial injury more than 1 year, delay to surgery from preoperative MRI more than 4 weeks, revisions, fracture histories, and multiple ligament injuries. According to preoperative MRI diagnosis, the meniscal tears were sorted into true-positive MRI and false-negative MRI groups. Multivariate logistic regression was used to analyze risk factors including age, gender, body mass index, time from injury to MRI, knee instability, concomitant ligament injury, intra-articular effusion, bone contusion, cartilage injury, meniscal tear location, and meniscal tear pattern.

RESULTS

Enrolled 249 meniscal tears (159 medial and 90 lateral menisci) were sorted into true-positive MRI (n = 136) and false-negative MRI (n = 113) groups. As time from injury to MRI diagnosis increased, the risk of the false-negative MRI diagnosis decreased (adjusted odds ratio [OR], 0.859; 95% confidence interval [CI], 0.802-0.921). Meniscal tear location within the posterior one-third was a significant risk factor compared with tear within the anterior one-third (adjusted OR, 11.823; 95% CI, 2.272-61.519). Peripheral longitudinal tear pattern was also a significant risk factor (adjusted OR, 3.522; 95% CI, 1.256-9.878).

CONCLUSIONS

Significant risk factors for false-negative MRI included short time from injury to MRI diagnosis, meniscal tear location within the posterior one-third, and peripheral longitudinal tear pattern.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Association of MRI findings and expert diagnosis of symptomatic meniscal tear among middle-aged and older adults with knee pain

Background

Our aim was to examine the association between an expert clinician’s impression of symptomatic meniscal tears and subsequent MRI in the context of middle-aged and older adults with knee pain.

Methods

Patients older than 45 were eligible for this IRB-approved substudy if they had knee pain, had not undergone MRI and saw one of two orthopaedic surgeons experienced in the diagnosis of meniscal tear. The surgeon rated their confidence that the patient’s symptoms were due to meniscal tear. The patient subsequently had a 1.5 or 3.0 T MRI within 6 months. We examined the association between presence of meniscal tear on MRI and the surgeon’s confidence that the knee pain was due to meniscal tear using a χ² test for trend.

Results

Of 84 eligible patients, 63 % were female, with a mean age of 64 years and a mean BMI of 27. The surgeon was confident that symptoms emanated from a tear among 39 %. The prevalence of meniscal tear on MRI overall was 74 %. Among subjects whose surgeon indicated high confidence that symptoms were due to meniscal tear, the prevalence was 80 % (95 % CI 63–90 %). Similarly, the prevalence was 87 % (95 % CI 62–96 %) among those whose surgeon had medium confidence and 64 % (95 % CI 48–77 %) among those whose surgeon had low confidence (p = 0.12).

Conclusion

Meniscal tears were frequently found on MRI even when an expert clinician was confident that a patient’s knee symptoms were not due to a meniscal tear, indicating that providers should use MRI sparingly and cautiously to confirm or rule out the attribution of knee pain to meniscal tear.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1010-2) contains supplementary material, which is available to authorized users.

A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears.

Anterior cruciate ligament injury: A persistently difficult diagnosis

BACKGROUND

Historically anterior cruciate ligament (ACL) injuries have been diagnosed poorly. A paper published in Injury in 1996 showed that less than 10% of patients with an ACL injury had the diagnosis made by the first physician to see them and that the average delay from first presentation to diagnosis was 21 months. The aim of our study was to investigate whether an improvement has been made over the last two decades in diagnosing ACL injuries.

METHODS

We identified 160 patients who had an ACL reconstruction performed by a single surgeon between October 2004 and December 2011 and for whom a complete data set was available. Data was extracted retrospectively from the hospital notes and a dedicated patient database. We performed a sub-group analysis comparing patients seen prior to the introduction of an acute knee injury clinic in April 2007 and patients seen after the introduction of the clinic.

RESULTS

75.1% (120/160) of patients presented first to an emergency department (ED) or to their general practitioner (GP), but only 14.4% (23/160) were diagnosed on initial presentation. The median number of healthcare professionals a patient saw prior to a diagnosis of ACL injury was 3. The median delay from injury to presentation was 0 weeks (range 0-885), injury to diagnosis 13 weeks (0-926), presentation to diagnosis 10 weeks (0-924), presentation to a specialist knee clinic 24 weeks (0-1006), and specialist knee clinic to surgery 13 weeks (0-102). The median total time from injury to surgery was 42 weeks (0-1047). Following the implementation of an acute knee injury clinic in 2007, the median delay from presentation to surgery dropped from 59 weeks to 36 weeks (p = 0.050) and there was a significant decrease in the median delay from specialist knee clinic to surgery from 23 to 11 weeks (p=0.002).

CONCLUSION

Over the past two decades there appears to have been little improvement in the early diagnosis of ACL injuries, with only 14.4% of patients being diagnosed correctly at initial presentation. We recommend further education of emergency and primary care clinicians in the diagnosis of ACL injuries, emphasising the importance of the typical history of an ACL injury. The implementation of an acute knee injury clinic may help minimise delays to surgery, which should result in better patient outcomes.

Diagnosis of ligamentous and meniscal pathologies in patients with anterior cruciate ligament injury: comparison of magnetic resonance imaging and arthroscopic findings

BACKGROUND

Magnetic resonance imaging (MRI) is routinely used to diagnose or support clinical diagnoses for meniscal or ligamentous injuries prior to offering patients arthroscopic treatment. However, the sensitivity of MRI for the detection of meniscal injury is not yet 100%. Sportsmen have occasionally returned to play with undiagnosed meniscal lesions on the basis of a normal MRI examination. This study was designed to assess the diagnostic parameters of MRI in patients with acute anterior cruciate ligament (ACL) injury.

METHODS

MRI and arthroscopic findings of 320 patients with acute ACL injury were included in this retrospective review. Patients belonged to a single surgeon from a high volume tertiary healthcare institution. All patients had either a MRI or an arthroscopic diagnosis of an acute ACL injury of one knee or both. All patients underwent therapeutic arthroscopy by the senior author routinely as part of arthroscopy-aided ACL reconstruction. Arthroscopic findings were the diagnostic reference based on which the positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity and concordance strength of association of MRI were calculated for ACL, posterior cruciate ligament (PCL), medial meniscus (MM) and lateral meniscus (LM) injuries.

RESULTS

MRI was most accurate in diagnosing cruciate ligament injuries with a PPV approaching 100%. The PPV of MRI in diagnosing meniscal injuries was approximately 60%. MRI was almost 100% sensitive and specific in diagnosing ACL injuries and 82% sensitive and 100% specific in diagnosing PCL injuries. Conversely, MRI was 77% sensitive and 90% specific in diagnosing MM injuries; and 57% sensitive and 95% specific in diagnosing LM injuries.

CONCLUSIONS

MRI remains the gold standard for diagnosing soft tissue injuries of the knee. However, there is a false positive rate ranging from 6% to 11% for meniscal tears.

Diagnosis of knee injuries: comparison of the physical examination and magnetic resonance imaging with the findings from arthroscopy

Objectives

To ascertain the sensitivity, specificity, accuracy and concordance of the physical examination (PE) and magnetic resonance imaging (MRI) in comparison with arthroscopy, in diagnosing knee injuries.

Methods

Prospective study on 72 patients, with evaluation and comparison of PE, MRI and arthroscopic findings, to determine the concordance, accuracy, sensitivity and specificity.

Results

PE showed sensitivity of 75.00%, specificity of 62.50% and accuracy of 69.44% for medial meniscal (MM) lesions, while it showed sensitivity of 47.82%, specificity of 93.87% and accuracy of 79.16% for lateral meniscal (LM) lesions. For anterior cruciate ligament (ACL) injuries, PE showed sensitivity of 88.67%, specificity of 94.73% and accuracy of 90.27%. For MM lesions, MRI showed sensitivity of 92.50%, specificity of 62.50% and accuracy of 69.44%, while for LM injuries, it showed sensitivity of 65.00%, specificity of 88.46% and accuracy of 81.94%. For ACL injuries, MRI showed sensitivity of 86.79%, specificity of 73.68% and accuracy of 83.33%. For ACL injuries, the best concordance was with PE, while for MM and LM lesions, it was with MRI (p < 0.001).

Conclusions

Meniscal and ligament injuries can be diagnosed through careful physical examination, while requests for MRI are reserved for complex or doubtful cases. PE and MRI used together have high sensitivity for ACL and MM lesions, while for LM lesions the specificity is higher.

Level of evidence II – Development of diagnostic criteria on consecutive patients (with universally applied reference “gold” standard).

Combined anterior and rotational knee laxity measurements improve the diagnosis of anterior cruciate ligament injuries

PURPOSE

This study analysed whether associating the side-to-side difference in displacement and the slope of the load-displacement curve of anterior and rotational knee laxity measurements would improve the instrumental diagnosis of anterior cruciate ligament (ACL) ruptures and help to detect different types of ACL tears.

METHODS

Anterior and rotational knee laxity was measured in 128 patients with an arthroscopically confirmed ACL injury and 104 healthy controls. Side-to-side differences were determined for three variables in anterior laxity: anterior displacement at 200 N (ATD200), primary compliance from 30 to 50 N (PCA) and secondary compliance from 100 to 200 N (SCA). Furthermore, four variables in rotational laxity were considered: internal and external rotation at 5 N m (IR5/ER5) and compliance from 2 to 5 N m (C IR/C ER). Receiver operating characteristic curves allowed to determine thresholds, specificities and sensitivities to detect ACL lesions, based on single variables considered and combinations thereof.

RESULTS

Sensitivity and specificity reached, respectively, 75 and 95 % for ATD200 (threshold: 1.2 mm) and 38 and 95 % for IR5 (threshold: 3.2°). If either two out of the three variables were positive for anterior laxity or both IR5 and C IR were positive, 81 % of patients were identified without a false positive. All patients for whom ATD200 was >3.7 mm, PCA > 48 μm/N or SCA > 17.5 µm/N had ACL remnants that were either totally resorbed or healed on the posterior cruciate ligament.

CONCLUSION

Combined instrumented anterior and rotational knee laxity measurements have excellent diagnostic value for ACL injury, provided that several measurements be considered concomitantly.

LEVEL OF EVIDENCE

Diagnostic study, Level III.

Diagnostic value of the clinical investigation in acute meniscal tears combined with anterior cruciate ligament injury using arthroscopic findings as golden standard

INTRODUCTION

The main purpose of our study was to evaluate the accuracy of clinical investigation for meniscal tears associated with ACL injuries. We hypothesized that combined ACL injury can decrease the accuracy of clinical examination in acute onset.

MATERIALS AND METHODS

One hundred and thirty-seven patients with a mean age of 28.5 years (from 12 to 55) were prospectively examined for acute combined ACL and meniscal injuries, between March and November 2012 at our department. For meniscal tears, clinical examination was performed using McMurray test, Apley test and medial and lateral joint line tenderness. The diagnoses of ACL tear were made using Lachman test, jerk test and pivot-shift test, anterior drawer test and KT-2000 side-to-side difference. Each patient was examined using X-ray and MRI. All the patients underwent arthroscopic surgery performed by the same surgeon within 6 weeks after the injury. Finally, using the arthroscopic findings as gold standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of clinical investigation and MRI were evaluated.

RESULTS

The specificity of clinical investigation was 63.5 and 46.0 % and the sensitivity was 74.4 and 77.3 % for the medial meniscus and the lateral meniscus, respectively. Overall, the accuracy of the clinical investigation was 70.3 % for the MM and 65.5 % for the lateral meniscus. The accuracy of MRI investigation was 76.4 and 69.5 % for medial and lateral meniscus, respectively.

DISCUSSION

In combined acute ACL injury and meniscal tears, we have found a decreased accuracy of the clinical investigation. The remnants of the torn ACL and the synovitis increased the rate of false positives, and it could simulate meniscal tears. However, clinical investigation can provide sufficient information for the treatment decision and MRI can be avoided as a routine diagnostic tool.

LEVEL OF EVIDENCE

Level II, prospective study.

The use of magnetic resonance imaging in acute knee injuries can be reduced by non-physician expert clinics

INTRODUCTION

The routine use of magnetic resonance imaging (MRI) for the assessment of acute knee injuries is controversial. The goal of this study is to present an audit of patients seen in a dedicated Acute Knee Injury Clinic (AKIC) to determine the frequency and appropriateness of MRI utilization.

METHODS

A retrospective review identified all patients who had an MRI and a randomly selected control group without MRI. The MRI was classified based on whether it was ordered by the AKIC team or by an external clinician. The consensus-based 'Indications for Urgent MRI in Acute Soft Tissue Knee Problems' were applied to both groups. An MRI was considered appropriate if any of the indications were met.

RESULTS

The overall MRI utilization rate was 23% (142/611). Of the MRIs performed, 32% (46/142) met the indications. About 94% (33/35) of the MRIs ordered by the AKIC experts met the indications, compared to only 12% (13/107) of those ordered externally. No patients in the control group met the indications. Diagnoses were similar between groups.

DISCUSSION

These results suggest that application of guidelines by experts in knee evaluation can significantly reduce expensive MRI utilization in patients with acute knee injuries without negatively impacting the appropriate diagnosis and disposition.

Clinical orthopedic examination findings in the lower extremity: correlation with imaging studies and diagnostic efficacy

The lower-extremity anatomy is complex and normal function is dependent on intact osteochondral, musculotendinous, and ligamentous structures. Injury may result in pain and functional limitation. Specific clinical tests are used to help isolate and define the pathoanatomy; however, their terminology may be confusing to the radiologist and the diagnostic value of these tests may not be well understood. This article presents an algorithmic approach to evaluation of the hip, knee, and ankle to improve the radiologist's understanding of lower-extremity physical examination. Knowledge of test terminology, clinical utility, and diagnostic accuracy will improve clinical and radiologic correlation. The article reviews the common clinical tests used to evaluate the lower extremity and provides an algorithm to establish a clinical examination road map and rapidly review the clinical utility and study hierarchy of a particular test. The sensitivity and specificity of the clinical tests and magnetic resonance (MR) imaging are reviewed because these parameters vary, and an understanding of the diagnostic utility of both the clinical and imaging tests is important in accurately formulating a definitive diagnosis. The structured algorithmic approach to lower-extremity examination described here, knowledge of test jargon, and familiarity with the diagnostic accuracy of the clinical and MR imaging examinations may help the radiologist focus image search patterns and provide detailed and clinically relevant reports. Online supplemental material is available for this article.

Indications requiring preoperative magnetic resonance imaging before knee arthroscopy

INTRODUCTION

Knee arthroscopy knee is gold standard in diagnosis and simultaneous treatment of knee disorders. But most patients undergo magnetic resonance imaging (MRI) before arthroscopy, although MRI results are not always consistent with arthroscopic findings. This raises the question in which suspected diagnoses MRI really has influence on diagnosis and consecutive surgical therapy.

MATERIAL AND METHODS

Preoperative MRI of 330 patients with knee disorders were compared with arthroscopic findings. The MRI were performed by 23 radiologists without specialization in musculoskeletal diagnostics. Specificity, sensitivity, negative/positive predictive value and accuracy of MRI were calculated in comparison to arthroscopic findings.

RESULTS

We found sensitivity/specificity of 58%/93% for anterior horn, 94%/46% for posterior horn of medial meniscus and 71%/81% for anterior and 62%/82% for posterior horn of lateral meniscus. Related to anterior cruciate ligament injuries we showed sensitivity/specificity of 82%/91% for grade 0 + I and 72%/96% for grade II + III. For Cartilage damage sensitivity/specificity of 98%/7% for grade I-, 89%/29% for grade II-, 96%/38% for grade III- and 96%/69% for grade IV-lesions were revealed.

CONCLUSIONS

The MRI should not be used as routine diagnostic tool for knee pain. No relevant information for meniscal lesions and anterior cruciate ligament ruptures has been gained with MRI from non-specialized outside imaging centres. The MRI should not be used as routine diagnostic tool for knee pain. No relevant information for meniscal lesions and anterior cruciate ligament ruptures has been gained with MRI from non-specialized outside imaging centres.

Evaluation of MRI versus arthroscopy in anterior cruciate ligament and meniscal injuries

AIMS AND OBJECTIVES

To find out the incidence of ACL & meniscal injuries, to co-relate MRI findings with arthroscopy by calculating Sensitivity, Specificity, Positive And Negative Predictive Values (PPV & NPV) keeping arthroscopy as a gold standard, to find out the degree of subluxation and to grade it and to find a threshold value of fluid in knee.

SETTINGS AND DESIGN

Prospective analytical study.

MATERIALS AND METHODS

MRI of 230 patients with 71 arthroscopic co- relation in year 2012-14 was analysed.

STATISTICAL ANALYSIS

Descriptive statistics using Chi square test and predictive values was done. The spearman correlation coefficient was done by using statistical software SPSS 17.0.

RESULTS

The sensitivity, specificity, PPV and NPV was calculated (in %). For ACL it was 87.87, 81.57, 80.55, 88.57 for MM 93.54, 87.50, 85.29, 94.59 and for LM 77.77, 81.81, 72.41, 85.71 respectively. We found 35.6% incidence of anterior tibial subluxation with maximum patients having grade 1 category subluxation. Two hundred and one cases showed joint fluid in lateral aspect of the suprapatellar pouch (AP diameter >10mm) with internal derangement.

CONCLUSION

MRI is helpful in diagnosing meniscal and cruciate ligament injuries. Arthroscopy still remains gold standard for definitive diagnosis.

Diagnostic needle arthroscopy and the economics of improved diagnostic accuracy: a cost analysis

BACKGROUND

Hundreds of thousands of surgical arthroscopy procedures are performed annually in the United States (US) based on MRI findings. There are situations where these MRI findings are equivocal or indeterminate and because of this clinicians commonly perform the arthroscopy in order not to miss pathology. Recently, a less invasive needle arthroscopy system has been introduced that is commonly performed in the physician office setting and that may help improve the accuracy of diagnostic findings. This in turn may prevent unnecessary follow-on arthroscopy procedures from being performed.

OBJECTIVE

The purpose of this analysis is to determine whether the in-office diagnostic needle arthroscopy system can provide cost savings by reducing unnecessary follow on arthroscopy procedures.

METHODS

Data obtained from a recent trial and from a systematic review were used in comparing the accuracy of MRI and VisionScope needle arthroscopy (VSI) with standard arthroscopy (gold standard). The resultant false positive and false negative findings were then used to evaluate the costs of follow-on procedures. These differences were then modeled for the US patient population diagnosed and treated for meniscal knee pathology (most common disorder) to determine if a technology such as VSI could save the US healthcare system money. Data on surgical arthroscopy procedures in the US for meniscal knee pathology were used (calendar year [CY] 2010). The costs of performing diagnostic and surgical arthroscopy procedures (using CY 2013 Medicare reimbursement amounts), costs associated with false negative findings, and the costs for treating associated complications arising from diagnostic and therapeutic arthroscopy procedures were assessed.

RESULTS

In patients presenting with medial meniscal pathology (International Classification of Diseases, 9th edition, Clinical Modification [ICD9CM] diagnosis 836.0), VSI in place of MRI (standard of care) resulted in a net cost savings to the US system of US$115-US$177 million (CY 2013) (use of systematic review and study data, respectively). In patients presenting with lateral meniscus pathology (ICD9CM 836.1), VSI in place of MRI cost the healthcare system an additional US$14-US$97 million (CY 2013). Overall aggregate savings for meniscal (lateral plus medial) pathology were identified in representative care models along with more appropriate care as fewer patients were exposed to higher risk surgical procedures.

CONCLUSIONS

Since in-office arthroscopy is significantly more accurate, patients can be treated more appropriately and the US healthcare system can save money, most especially in medial meniscal pathology.

Efficacy of magnetic resonance imaging evaluation for meniscal tear in acute anterior cruciate ligament injuries

PURPOSE

The objective of this study was to compare the preoperative magnetic resonance imaging (MRI) diagnostic rates of meniscal injuries combined with acute anterior cruciate ligament (ACL) injuries, as well as traumatic meniscal injuries without ACL injuries.

METHODS

From January 2005 through April 2013, 208 patients who underwent ACL reconstruction and 1,334 patients with traumatic meniscal tear injuries were examined by MRI and arthroscopy. Patients with chronic ACL injuries, revisions, fracture histories, or multiple-ligament injuries and patients with Outerbridge degenerative changes of grade 3 or greater were excluded, yielding 159 patients and 621 patients in the 2 groups, respectively. The medial meniscus (MM) and lateral meniscus (LM) examined by MRI and arthroscopy for findings of tears were compared in each group. The sensitivity, specificity, positive predictive value, and negative predictive value for MM and LM tears by MRI were compared and analyzed statistically.

RESULTS

The diagnostic sensitivity of MRI in the group with ACL injury was significantly lower than that in the ACL-intact group for the MM (P < .001) and LM (P = .040). The negative predictive value was also lower in the group with ACL injury for both the MM (P = .008) and LM (P < .001). There was no statistical difference in specificity and positive predictive value between the 2 groups.

CONCLUSIONS

This study showed that if a patient had an acute ACL tear, the sensitivity and negative predictive value of MRI for a meniscal tear were less than if there was no ACL tear, which led to the low diagnostic accuracy of MRI.

LEVEL OF EVIDENCE

Level III, retrospective case-control study.

Joint line tenderness and McMurray tests for the detection of meniscal lesions: what is their real diagnostic value?

OBJECTIVES

To assess the interobserver concordance of the joint line tenderness (JLT) and McMurray tests, and to determine their diagnostic efficiency for the detection of meniscal lesions.

DESIGN

Prospective observational study.

SETTING

Orthopedics outpatient clinic, university hospital.

PARTICIPANTS

Patients (N=60) with suspected nonacute meniscal lesions who underwent knee arthroscopy.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Patients were examined by 3 independent observers with graded levels of experience (>10y, 3y, and 4mo of practice). The interobserver concordance was assessed by Cohen-Fleiss κ statistics. Accuracy, negative and positive predictive values for prevalence 10% to 90%, positive (LR+) and negative (LR-) likelihood ratios, and the Bayesian posttest probability with a positive or negative result were also determined. The diagnostic value of the 2 tests combined was assessed by logistic regression. Arthroscopy was used as the reference test.

RESULTS

No interobserver concordance was determined for the JLT. The McMurray test showed higher interobserver concordance, which improved when judgments by the less experienced examiner were discarded. The whole series studied by the "best" examiner (experienced orthopedist) provided the following values: (1) JLT: sensitivity, 62.9%; specificity, 50%; LR+, 1.26; LR-, .74; (2) McMurray: sensitivity, 34.3%; specificity, 86.4%; LR+, 2.52; LR-, .76. The combination of the 2 tests did not offer advantages over the McMurray alone.

CONCLUSIONS

The JLT alone is of little clinical usefulness. A negative McMurray test does not modify the pretest probability of a meniscal lesion, while a positive result has a fair predictive value. Hence, in a patient with a suspected meniscal lesion, a positive McMurray test indicates that arthroscopy should be performed. In case of a negative result, further examinations, including imaging, are needed.

The role of MRI in musculoskeletal practice: a clinical perspective

This clinical perspective presents an overview of current and potential uses for magnetic resonance imaging (MRI) in musculoskeletal practice. Clinical practice guidelines and current evidence for improved outcomes will help providers determine the situations when an MRI is indicated. The advanced competency standard of examination used by physical therapists will be helpful to prevent overuse of musculoskeletal imaging, reduce diagnostic errors, and provide the appropriate clinical context to pathology revealed on MRI. Physical therapists are diagnostically accurate and appropriately conservative in their use of MRI consistent with evidence-based principles of diagnosis and screening.