The impact of magnetic resonance imaging of the knee on surgical decision making

Impact of job characteristics on return-to-work interval following arthroscopic partial meniscectomy

The aim of this paper was to investigate whether job characteristics are associated with time interval for return to former professional activity (return to work, RTW) after arthroscopic partial meniscectomy (APM). A retrospective study was carried out in a sample of 63 patients in working age who underwent an APM between July 2018 and July 2020. The following preoperative characteristics were assessed: age at surgery, meniscal side, sex, physical job demands (white versus blue collar worker), telework and work status (salaried versus self- employed). A linear regression analysis was used to study the association between job characteristics and RTW interval adjusted for socio-demographic and medical (meniscal side) factors. Telework was most strongly associated with interval for RTW (p <0,001, adjusted R Square: 20,8). The results suggested that telework supports early RTW independently of sociodemographic and medical factors. This study supported the need for a tailormade approach in the prescription of sick leave.

Incorporation of Hamstring Grafts Within the Tibial Tunnel After Anterior Cruciate Ligament Reconstruction: Magnetic Resonance Imaging of Suspensory Fixation Versus Interference Screws

BACKGROUND

The success of anterior cruciate ligament (ACL) reconstruction requires solid graft incorporation within the tunnels to enable graft remodeling. Resorbable interference screws (RIS) provide limited tendon-bone contact because much of the tunnel circumference is occupied by the screw itself, while adjustable suspensory fixation (ASF) systems provide larger contact zones, which favor ligamentization.

PURPOSE

To evaluate ligamentization of a 4-strand semitendinosus (4ST) graft fixed with ASF compared with RIS within the tibial bone tunnel at 6 months postoperatively using magnetic resonance imaging (MRI).

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

We prospectively enrolled 121 consecutive patients undergoing primary ACL reconstruction using a single-bundle 4ST graft. The femoral end of the graft was fixed using suspensory fixation in all knees. The tibial end of the graft was fixed using ASF in 67 knees and RIS in 54 knees. Six months postoperatively, knee laxity measurements were taken, and MRI was performed to assess graft incorporation within the tibial tunnel.

RESULTS

At 6-month follow-up, MRI scans of 109 knees were available for analysis. The mean tibial tunnel enlargement in the ASF group was 2.3 ± 1.1 mm (range, 0.5-6.0 mm), while in the RIS group, it was 4.7 ± 2.8 mm (range, 0.5-19.0 mm) (P < .001). The Howell graft signal assessment findings were excellent in 97% of knees in the ASF group and in 25% of knees in the RIS group (P < .001). The mean signal-to-noise quotient (SNQ) was 0.078 ± 0.62 in the ASF group and 0.671 ± 0.83 in the RIS group (P < .001).

CONCLUSION

ASF provides more favorable conditions than RIS for the incorporation and ligamentization of 4ST grafts within the tibial tunnel. The ASF system used showed very little tunnel widening, which suggests that it grants stabilization. The SNQ was also considerably better in the ASF group.

Arthroscopic patterns of the poster-medial aspect of the knee joint: classification of the gastrocnemius-semimembranosus gateway and its relationship with Baker's cyst

BACKGROUND

The gastrocnemius-semimembranosus bursa may communicate with the knee joint. The arthroscopic anatomy of the posteromedial aspect varies depending on the angle of the oblique popliteal ligament, the level at which it crosses the medial gastrocnemius tendon, and its relationship with the capsular joint and synovia. The aim of this paper is to identify possible patterns, and to evaluate their characteristics and their relationship with Baker's cyst.

METHODS

data archived from 185 consecutive arthroscopies were evaluated; an anatomic description and classification was carried out; the percentages of association with BC and the associated pathologies were reported.

RESULTS

The different anatomies were classified into six groups based on the relationship above the medial gastrocnemius tendon, the capsular joint and synovia. The prevalence of Baker's cyst was 28.3%. The main associated intra-articular pathological condition was the contemporary presence of a meniscal tear and chondropathy.

CONCLUSION

Exploration of the posterior aspect of the knee must be performed routinely. Knowing the possible anatomy patterns of the posteromedial arthroscopic aspect of the knee joint could help to identify the cyst and its gateway, thus facilitating its treatment.

LEVEL OF THE EVIDENCE

III.

Accuracy of magnetic resonance imaging of the knee in the community setting

BACKGROUND

Magnetic resonance imaging (MRI) is routinely used in the diagnosis of sports-related knee injuries.

PURPOSE

To determine the accuracy, sensitivity, and specificity of MRI compared with clinical evaluation in the diagnosis of meniscal pathology when the MRI facility and the radiologist are not preselected.

METHODS

A total of 288 knee arthroscopies were retrospectively compared. Patients were divided into 3 groups: those who had MRI performed and interpreted at a single institution, MRI performed and interpreted at community facilities, or a clinical evaluation by a senior orthopaedic surgeon.

RESULTS

The sensitivity, specificity, and accuracy of the diagnosis of medial meniscal pathology at a single institution were 90%, 59%, 76%; in community facilities, 73%, 68%, 70%; and by a clinical evaluation, 93%, 55%, 73%, respectively. For lateral meniscal pathology, the results were as follows: single institution, 75%, 76%, 81%; community facilities, 60%, 88%, 79%; and clinical evaluation, 45%, 90%, 79%, respectively. Sensitivity for medial meniscus was greater than for lateral meniscus, but specificity of diagnosis was better for lateral meniscus by MRI and clinical evaluation. While not statistically significant, there was increased sensitivity in the diagnosis of medial meniscus and lateral meniscus at SIs, but they have less specificity than at community facilities. The number of false-positive diagnoses (ie, no intra-articular pathology) that resulted in surgery was 4 of 288 (1.39%). The overall accuracy for medial meniscus by MRI was 73% vs 73% for clinical evaluation. The overall accuracy for MRI for lateral meniscus was 78% vs 79% for clinical evaluation.

CONCLUSION

Routine MRI may not be more beneficial than clinical evaluation when there is no preselection of MRI facility and interpreting radiologist.

CLINICAL RELEVANCE

The use of MRI for diagnosing meniscal pathology should be reserved for those cases where the orthopaedic clinical examination is ambiguous.

Arthroscopic verification of objectivity of the orthopaedic examination and magnetic resonance imaging in intra-articular knee injury. Retrospective study

Introduction

Arthroscopy of the knee joint is regarded as the most objective diagnostic method in intra-articular knee joint lesions.

Aim

The purpose of this study was to assess the objectivity and diagnostic value of orthopaedic examination (OE) and magnetic resonance imaging (MRI) in reference to the arthroscopic result.

Material and methods

In a group of 113 patients treated by arthroscopic surgery for post-traumatic knee pathology between 2008 and 2010 in our department, accuracy of clinical and MRI findings that preceded surgery were studied retrospectively using a statistical method. Sensitivity, specificity, accuracy and predictive negative and positive values were the subject of analysis.

Results

In the presented trial, sensitivity values of the orthopaedic examination for injuries of the anterior cruciate ligament (ACL), meniscus medialis (MM), meniscus lateralis (ML) and chondral injuries (ChI) were 86%, 65%, 38% and 51%, respectively. Specificity values were 90%, 65%, 100% and 100%, respectively. The MR sensitivity and specificity values were 80%, 88%, 44% and 32%, and 86%, 64%, 93% and 97%, respectively.

Conclusions

Assessment of intra-articular knee joint lesions is a difficult diagnostic problem. In making a decision about arthroscopy of the knee joint, an appropriate sequence of examinations should be carried out: OE, MRI and arthroscopy. The improvement in the effectiveness of the orthopaedic examination and MRI can limit the too high frequency of diagnostic arthroscopies, which generates the risk of operation treatment and costs.

MRI efficacy in diagnosing internal lesions of the knee: a retrospective analysis

BACKGROUND

Many surgeons tend to believe that MRI is an accurate, non invasive diagnostic method, enough to lead to decisions for conservative treatment and save a patient from unnecessary arthroscopy. We conducted a retrospective study to investigate the accuracy of the MRI of the knee for the detection of injuries of the meniscus, cruciate ligaments and articular cartilage, in comparison with the preoperative clinical examination and intraoperative findings. Between May 2005 and February 2006 102 patients after clinical examination were diagnosed with meniscal or cruciate injury and underwent definitive treatment with arthroscopy. 46 of these patients fulfilled the inclusion criteria. The accuracy, sensitivity, specificity, negative and positive predictive values of the MRI findings were correlated with the lesions identified during arthroscopy. The diagnostic performance of the initial clinical examination was also calculated for the meniscal and cruciate ligament injuries.

RESULTS

The accuracy for tears of the medial, lateral meniscus, anterior and posterior cruciate ligaments and articular cartilage was 81%, 77%, 86%, 98% and 60% respectively. The specificity was 69%, 88%, 89%, 98% and 73% respectively. The positive predictive value was 83%, 81%, 90%, 75% and 53% respectively. Finally, the clinical examination had significant lower reliability in the detection of these injuries.

CONCLUSION

MRI is very helpful in diagnosing meniscal and cruciate ligament injuries. But in a countable percentage reports with false results and in chondral defects its importance is still vague. The arthroscopy still remains the gold standard for definitive diagnosis.

The effect of magnetic resonance imaging scans on knee arthroscopy: randomized controlled trial

PURPOSE

The purpose of this study was to investigate whether magnetic resonance imaging (MRI) in patients waiting for knee arthroscopy could reduce arthroscopy rates and improve patient outcome.

METHODS

A prospective randomized controlled trial was conducted in a teaching hospital setting. All participating patients had knee MRI before arthroscopy. In the intervention group the MRI report was seen by surgeons, and in the control group it was not. The primary outcome measure was the proportion of patients who did not have an arthroscopy. Secondary outcome measures included the Short Form 36, EuroQol EQ-5D, Knee Injury and Osteoarthritis Score, and Knee Society Score.

RESULTS

Surgeons changed both their diagnosis and management plan in 47% of patients in the intervention group compared with 1% in the control group, with no difference between groups in the proportion of patients who underwent an arthroscopy. In the intervention group 7 of 125 patients (5.6%) did not have an arthroscopy compared with 8 of 127 patients (6.3%) in the control group. In one instance a surgeon decided against arthroscopy based on the MRI report. There was no significant difference between groups in other outcome measures.

CONCLUSIONS

We found no effect of MRI on the decision to perform arthroscopy or patient outcome. Performing MRI in patients already on the waiting list for arthroscopy may not be effective in reducing utilization of surgery.

LEVEL OF EVIDENCE

Level I, therapeutic randomized controlled trial with no statistically significant difference but with narrow confidence intervals.

Magnetic resonance imaging abnormalities in symptomatic and contralateral knees: prevalence and associations with traumatic history in general practice

BACKGROUND

After trauma, internal knee lesions are found in approximately two thirds of patients. However, magnetic resonance imaging abnormalities have also been described in asymptomatic volunteers.

HYPOTHESIS

Not all visualized lesions in symptomatic posttraumatic knees are the result of recent trauma; there are subgroups of lesions that may be preexistent.

STUDY DESIGN

Cross-sectional study (prevalence); Level of evidence, 2.

METHODS

Patients visiting their general practitioners after knee trauma were invited for magnetic resonance imaging of both knees. Prevalence of knee abnormalities was compared between symptomatic and asymptomatic knees. Multivariable analysis was performed to investigate the association between lesions that were seen in symptomatic and asymptomatic knees (ie, effusion and meniscal tears) and recent trauma, history of old trauma, age, and osteoarthritis.

RESULTS

In 134 participants, ligament lesions were found almost exclusively in symptomatic knees. Meniscal lesions and effusion were almost equally found in symptomatic and asymptomatic knees. Effusion was related to recent trauma (odds ratio, 14.0; 95% confidence interval, 5.0-39.6) and osteoarthritis (odds ratio, 4.7; 95% confidence interval, 1.4-15.5) but not to history of old trauma and age. Meniscal tears were more common in older patients (odds ratio, 1.09; 95% confidence interval, 1.05-1.12) but were not related to osteoarthritis. History of old trauma was more strongly related to the group of radial, longitudinal, and complex meniscal tears (odds ratio, 8.6; 95% confidence interval, 3.3-22.5) than to horizontal tears (odds ratio, 2.3; 95% confidence interval, 0.9-5.6). Recent trauma was not related to horizontal meniscal tears but was strongly related to other types of meniscal tears (odds ratio, 3.2; 95% confidence interval, 1.4-6.9).

CONCLUSION

Ligament knee lesions are most probably the result of recent trauma. Radial, longitudinal, and complex meniscal tears are strongly related to trauma, whereas horizontal meniscal tears and effusion may be preexistent in many cases.

Imaging evaluation of meniscal injury of the knee joint: a comparative MR imaging and arthroscopic study

To evaluate the efficacy of MR imaging in the diagnosis and classification of meniscal tear of the knee joint, we retrospectively characterized the MR features of 78 meniscal tears in 148 patients according to the Mesgarzadeh's criteria. The results showed that the sensitivity and specificity for meniscal tears were 92% and 87%, respectively. Type VI meniscal tear was the most common type, especially in displaced meniscal tear. MR is a reliable diagnostic tool for meniscal tears and associated cruciate ligament injury.

Clinical decision making in the acutely injured knee based on repeat clinical examination and MRI

To determine the correlation between Magnetic Resonance Imaging (MRI) and clinical examination of the knee after an acute injury, and to see to what extent MRI affected the planned treatment, we examined 90 consecutive patients in a prospective study, clinically and with an extremity Magnetic Resonance (MR) scanner. The number of meniscal lesions, bone bruises and osteochondral lesions found on MRI was significantly higher than the clinical examinations indicated. Despite this, the treatment was only changed in 6 cases. In no case did MRI prevent a planned arthroscopy. MRI may reveal many clinically silent changes in the knee, also after minor injuries. The significance of these MRI findings must await long-term follow-up.

The accuracy of three-dimensional reconstructions of the ovine knee: dissectional validation

A single, complete, ovine knee was imaged using conventional MRI then dissected allowing comprehensive dimensional measurement of the intra-articular structures. A three-dimensional (3-D) computer model of the knee was generated from the MR sections. Thirty-two individual structural measures were recorded from the image output for which there was an available surgical measure for direct comparison. The results of Pearson's correlation testing show a rounded score of 1.00, suggesting an exceptional linear correlation between direct anatomical measurement and the 3-D image output. Further analysis of the data revealed an average error of measurement of 0.2mm across the 32 measures. The findings of this preliminary study suggest that 3-D reconstruction from MR data may be an appropriate, and accurate, means for making dimensional measurements of the bony and soft tissue structures of the ovine knee. It is unlikely that the measurement error would be of any great clinical significance. There is evidence in the literature to suggest that an ovine knee may be considered an acceptable model for substitution for the human knee in diagnostic assessment studies. Therefore, such findings may be considered clinically relevant in the field of human knee assessment.

Comparison of knee magnetic resonance imaging findings in patients referred by orthopaedic surgeons versus nonorthopaedic practitioners

PURPOSE

To compare the percentages of normal magnetic resonance imaging (MRI) examination results and clinically significant knee abnormalities in patients referred for MRI of the knee by orthopaedic surgery residents and staff with those of patients referred by nonorthopaedic practitioners.

TYPE OF STUDY

Retrospective review of MRI findings.

METHODS

MRI reports of 754 patients (454 men and 300 women) were retrospectively reviewed; 373 patients were referred from the Department of Orthopaedic Surgery and 381 patients were referred from nonorthopaedic practitioners. The number of normal examination results, meniscal and ligament tears, chondral abnormalities, and Baker's cysts was tabulated and analyzed using a X-square injury analysis.

RESULTS

The rate of normal results for nonorthopaedic practitioners was 33.9% (129 of 381) compared with 15.3% (57 of 373) for orthopaedic surgeons (P <.001). Nonorthopaedic surgeons referred 69.4% (129 of 186) of the patients who had normal examination results. The positive finding for a lateral meniscus tear was 29.2% (109 of 373) for orthopaedic surgeons compared with 19.1% (73 of 381) for nonorthopaedic practitioners, which was statistically significant (P =.002) in regard to the distribution of injuries. No difference was found in other abnormalities assessed.

CONCLUSIONS

Patients referred by nonorthopaedic practitioners had significantly more normal knee MRI examination results than did those referred by orthopaedic surgeons.

Biomechanical properties and vascularity of an anterior cruciate ligament graft can be predicted by contrast-enhanced magnetic resonance imaging. A two-year study in sheep

Magnetic resonance imaging has been used to determine graft integrity and study the remodeling process of anterior cruciate ligament grafts morphologically in humans. The goal of the present study was to compare graft signal intensity and morphologic characteristics on magnetic resonance imaging with biomechanical and histologic parameters in a long-term animal model. Thirty sheep underwent anterior cruciate ligament reconstruction with an autologous Achilles tendon split graft and were sacrificed after 6, 12, 24, 52, or 104 weeks. Before sacrifice, all animals underwent plain and contrast-enhanced (gadolinium-diethylenetriamine pentacetic acid) magnetic resonance imaging (1.5 T, proton density weighted, 2-mm sections) of their operated knees. The signal/noise quotient was calculated and data were correlated to the maximum load to failure, tensile strength, and stiffness of the grafts. The vascularity of the grafts was determined immunohistochemically by staining for endothelial cells (factor VIII). We found that high signal intensity on magnetic resonance imaging reflects a decrease of mechanical properties of the graft during early remodeling. Correlation analyses revealed significant negative linear correlations between the signal/noise quotient and the load to failure, stiffness, and tensile strength. In general, correlations for contrast-enhanced measurements of signal intensity were stronger than those for plain magnetic resonance imaging. Immunohistochemistry confirmed that contrast medium enhancement reflects the vascular status of the graft tissue during remodeling. We conclude that quantitatively determined magnetic resonance imaging signal intensity may be a useful tool for following the graft remodeling process in a noninvasive manner.

Recommendations for the diagnosis of traumatic meniscal injuries in athletes

It has always been difficult to develop a method of correctly evaluating knee injuries and, in turn, to devise the appropriate rehabilitation programme. Flawless diagnosis of meniscal injury is necessary, considering the diverse consequences of this injury for patients, and even more so in relation to athletes, bearing in mind the intensified physical demands on their bodies. There is no doubt that an accurate and concise clinical evaluation of patients with injuries to the knee is the basis for an exact diagnosis and successful treatment. The use of noninvasive methods, such as magnetic resonance imaging, in addition to clinical evaluation is recommended because of their high accuracy and negative predictive value. The use of invasive methods, such as arthroscopic operations, should be restricted to treatment, and not be used for diagnosis.