Superior labrum anterior-posterior lesions: diagnosis with MR arthrography of the shoulder

Preliminary exploration of deep learning-assisted recognition of superior labrum anterior and posterior lesions in shoulder MR arthrography

PURPOSE

MR arthrography (MRA) is the most accurate method for preoperatively diagnosing superior labrum anterior-posterior (SLAP) lesions, but diagnostic results can vary considerably due to factors such as experience. In this study, deep learning was used to facilitate the preliminary identification of SLAP lesions and compared with radiologists of different seniority.

METHODS

MRA data from 636 patients were retrospectively collected, and all patients were classified as having/not having SLAP lesions according to shoulder arthroscopy. The SLAP-Net model was built and tested on 514 patients (dataset 1) and independently tested on data from two other MRI devices (122 patients, dataset 2). Manual diagnosis was performed by three radiologists with different seniority levels and compared with SLAP-Net outputs. Model performance was evaluated by the receiver operating characteristic (ROC) curve, area under the ROC curve (AUC), etc. McNemar's test was used to compare performance among models and between radiologists' models. The intraclass correlation coefficient (ICC) was used to assess the radiologists' reliability. p < 0.05 was considered statistically significant.

RESULTS

SLAP-Net had AUC = 0.98 and accuracy = 0.96 for classification in dataset 1 and AUC = 0.92 and accuracy = 0.85 in dataset 2. In dataset 1, SLAP-Net had diagnostic performance similar to that of senior radiologists (p = 0.055) but higher than that of early- and mid-career radiologists (p = 0.025 and 0.011). In dataset 2, SLAP-Net had similar diagnostic performance to radiologists of all three seniority levels (p = 0.468, 0.289, and 0.495, respectively).

CONCLUSIONS

Deep learning can be used to identify SLAP lesions upon initial MR arthrography examination. SLAP-Net performs comparably to senior radiologists.

Shoulder magnetic resonance arthrography in dogs: Comparison of craniolateral and caudolateral approach for ultrasound-guided contrast injection

Shoulder joint disease is a common cause of forelimb lameness in dogs. To diagnose this condition, shoulder magnetic resonance arthrography (MRA) is performed, which involves the injection of contrast agents into the shoulder joint space under ultrasound (US)-guidance. The objective of this study was to compare the craniolateral and caudolateral approaches for shoulder MRA using US-guided injection techniques, and investigate their clinical feasibility in dogs. Forty shoulder joints from 10 adult beagles were studied in two repetitions. The craniolateral (n = 20) and caudolateral (n = 20) injection techniques were applied randomly under US-guidance. The shoulder MRA was conducted immediately after the contrast agents was injected. The procedure time (scan and injection time), number of attempts, joint distension and degree of extraarticular extravasation were recorded and compared between the two groups. The results showed that the caudolateral approach had significantly more contrast agents extravasation compared to the craniolateral approach (p < 0.05). However, there were no significant differences between the two groups in terms of procedure time (scan time p = 0.80, injection time p = 0.74), number of attempts (p = 0.70) and joint distension (p = 0.23). The craniolateral approach of US-guided contrast injection techniques for shoulder MRA minimizes damage to the juxta-articular structures and reduces extraarticular extravasation, resulting in good-quality images. This study demonstrates the feasibility and advantages of the craniolateral approach under US-guidance for shoulder MRA in dogs.

Glenohumeral Pathologies following Primary Anterior Traumatic Shoulder Dislocation-Comparison of Magnetic Resonance Arthrography and Arthroscopy

BACKGROUND

We assessed intraarticular injuries in patients after primary anterior traumatic shoulder dislocation by comparing magnetic resonance arthrography (MRA) results with concomitant arthroscopic findings.

METHODS

All patients with primary traumatic shoulder dislocation who underwent arthroscopic surgery between 2001 and 2020 with preoperative MRA were included in this study. MRA was retrospectively compared with arthroscopic findings. Postoperative shoulder function was prospectively assessed using the Disabilities of Arm, Shoulder and Hand score (quick DASH), the Oxford Shoulder Score (OSS), the Subjective Shoulder Value (SSV), as well as the rate of return to sports.

RESULTS

A total of 74 patients were included in this study. A Hill-Sachs lesion was consistently found in the corresponding shoulders on MRA and arthroscopy in 35 cases (p = 0.007), a Bankart lesion in 37 shoulders (p = 0.004), and a superior labrum from anterior to posterior (SLAP) lesion in 55 cases (p = 0.581). Of all cases, 32 patients were available for a clinical and functional follow-up evaluation. A positive correlation was found between the level of sport practiced and the Oxford Shoulder Score (redislocation subset) (p = 0.032) and between the age at the time of surgery and the follow-up SSV (p = 0.036). Conversely, a negative correlation was observed between the age at the time of surgery and the Oxford Instability Score (redislocation subset) (p = 0.038).

CONCLUSIONS

The results of this study show a good correlation between MRA and arthroscopy. Therefore, MRA is a valid tool for the detection of soft tissue pathologies after primary anterior traumatic shoulder dislocation and can aid in presurgical planning.

Imaging Posterior Instability of the Shoulder

Posterior instability of the shoulder is much less common than anterior instability with a clinical presentation that is often less obvious, making the diagnosis more challenging and more easily missed. We describe the imaging findings of posterior instability so the radiologist can make the diagnosis and provide a detailed description, enabling the surgeon to make more informed decisions regarding management and surgery.

The Top 50 Most-Cited Papers in the Diagnosis and Management of SLAP Tears

Purpose

To identify and characterize the top 50 most-cited articles regarding SLAP tears.

Methods

Referencing the methodology of previous citation analyses, varying Boolean searches were performed using the Web of Science database and the search terms yielding the greatest number of results was used. The top 50 most-cited articles were identified and the following data points were gathered from each article: author, institution, country of origin, year of publication, publishing journal, level of evidence, and citation density.

Results

The total number of citations was 7834, with a median of 106 citations. The top 50 list was largely composed of diagnostic level I, II, and III studies (5, 7, and 8 total publications, respectively) and therapeutic level III (6 publications) or level IV (10 publications). Most articles originated from the United States (40). In total, 19 of the top 50 most-cited articles were published in the American Journal of Sports Medicine, followed by Arthroscopy (15) and the Journal of Bone and Joint Surgery (5).

Conclusions

Our analysis demonstrated a correlation with earlier publications being cited more frequently than recent studies. Importantly, the current study found that therapeutic studies in the most cited list were largely level III or level IV evidence. This makes the management of SLAP tears seem anecdotal, with little in the way of high-impact level I or level II therapeutic studies. We must reconsider our current understanding of SLAP tears and their management with more studies that demonstrate a clearer treatment algorithm for these common injuries of the shoulder.

Clinical Relevance

Given the complexity of SLAP tears, this list of the most-cited articles can provide a reference point to better guide practice, resident education, and future areas of orthopaedic research.

The Fifty Most-Cited Articles Regarding SLAP Lesions

Purpose

To identify and evaluate the top 50 most-cited articles pertaining to SLAP tears.

Methods

The ISI Web of Knowledge database was used to conduct a query for articles pertaining to SLAP tears. Our query was conducted in April 2020 with multiple Boolean operative combinations performed by 2 independent reviewers. Articles on the final list were further reviewed to extract the following data: manuscript title, first author, total citation count, year of publication, citation density since publication, current citation rate since 2013, journal, country of origin, and level of evidence.

Results

Our initial search yielded 2,597 articles. Within this cohort, the top 50 publications pertaining to SLAP tears were identified that met our search criteria. The top article was cited 802 times while the 50th ranked article was cited 46 times. The average number of citations per publication was 131, whereas the average citation density since year of publication was 7.3. No strong correlations were found between citation density and year published. Twelve journals published articles pertaining to SLAP tears, with Arthroscopy accounting for the greatest number (15 articles, 30%). Most articles were graded with a level of evidence (LOE) of IV (n = 24, 48%), followed by review articles without LOE (n = 8, 16%). Only 2 articles achieved an LOE of I (4%). Articles typically addressed the arthroscopic management (n = 11, 22%), whereas anatomy/classification (n =10, 20%), and outcomes (n = 9, 18%) also were reported.

Conclusions

This review provides a quantitative analysis of the most-referenced literature pertaining to SLAP tears. This body of knowledge helps surgeons search for literature regarding these injuries and identify trends regarding SLAP tear research.

Clinical Relevance

This research provides practitioners with an easily accessible and comprehensive collection of the major contributions regarding SLAP tears and offers insight into future areas for research.

Shoulder MR Arthrography: Comparative Evaluation of Three Different Contrast Injection Techniques Using an Anterior Approach

BACKGROUND

MR arthrography (MRA) is commonly used in the assessment of shoulder internal derangements. Correct intra-articular contrast injection is required for this modality. Anterior injections under fluoroscopic, ultrasound-guidance, or without image-guidance have been described in the literature. However, no simultaneous comparison has been performed between the three techniques.

PURPOSE

To compare the accuracy and performance of fluoroscopy (FL)-guided, ultrasound (US)-guided and non-image-guided intra-articular contrast injection via an anterior approach for performing shoulder MRA.

STUDY TYPE

Prospective.

SUBJECTS

Two-hundred and ten patients (180 men and 30 women; mean age, 33 ± 12 years; range 20-60 years) with clinically suspected shoulder pathology.

FIELD STRENGTH/SEQUENCE

1.5T/fat-suppressed T₁ -weighted, T₂ -weighted, and 3D-gradient-echo images.

ASSESSMENT

Patients underwent shoulder MRA after anterior intra-articular contrast injection under FL- or US-guidance or without image-guidance. Patients were randomized among the three techniques with each group comprising 70. The techniques were compared according to the accuracy of intra-articular needle placement, attempts success rate, pain during and 24 hours after injection, procedure times, contrast extravasation rate, joint distension, and MRA diagnostic efficacy. Pain was assessed by the visual analog scale (VAS) pain-score.

STATISTICAL TESTS

Pearson's chi-squared and Kruskal-Wallis tests.

RESULTS

FL- and US-guided injections (100% accuracy) were significantly more accurate than non-image-guided (85.7% accuracy) (P < 0.05). US-guidance was the least painful, with statistical differences between image-guided and non-image-guided techniques regarding the first attempt success rate (95.7% and 92.8% for FL- and US-guided vs. 78.6% for blinded), VAS-score 24 hours-post-procedure (1.7 ± 1.7, and 1.5 ± 1.4 vs. 2.2 ± 1.4), procedure time (11.9 ± 1.6, and 7.4 ± 1.7 vs. 4.3 ± 0.76 minutes), and contrast extravasation rate (5.7%, and 8.6% vs. 30%) (all P < 0.05). Procedure time was also significantly different between FL and US-guidance (P < 0.05).

DATA CONCLUSION

Imaging-guided injections are more accurate and tolerable than non-image-guided and should be considered to confirm intra-articular needle position, hence adequate capsular distension and good diagnostic quality of shoulder MRA. US guidance is a less painful, rapid, and safe alternative to the FL approach. Evidence Level: 2 Technical Efficacy Stage: 5. J. MAGN. RESON. IMAGING 2021;53:481-490.

National Trends in the Repair of Isolated Superior Labral Tear from Anterior to Posterior in Korea

BACKGROUND

The optimal treatment for superior labral tear from anterior to posterior (SLAP) lesions is controversial. Thus, we aimed to investigate the national surgical trends in isolated SLAP repair in Korea.

METHODS

We analyzed a nationwide database from the Korean Health Insurance Review and Assessment Service from 2008 to 2017. We investigated the trends in SLAP repair by time, sex, age, and the type of health care institution.

RESULTS

From 2008 to 2017, 27,850 isolated SLAP repairs were identified. Age-adjusted incidence rate of isolated SLAP repair increased by 692% from 1.07/100,000 in 2008 to 8.48/100,000 in 2012 (P = 0.005). However, the incidence rate declined significantly after 2012 (P = 0.032) and was 5.28/100,000 in 2017. Sex-specific incidence rate of isolated SLAP repair was 2.3 times higher in men than in women. The decline since 2012 was most evident in patients aged ≥ 40 years (P = 0.01); however, the incidence rates of isolated SLAP repair during the study period were similar between patients aged ≥ 40 years and those aged < 40 years. Moreover, hospitals with 30-100 beds had the greatest change in the number of isolated SLAP repair cases.

CONCLUSION

In Korea, the incidence of isolated SLAP repair increased dramatically until 2012; since then, it has declined. Although the decrease in isolated SLAP repair later in the study was evident in those aged ≥ 40 years, the incidence rate was still relatively high in patients aged ≥ 40 years.

High Prevalence of Superior Labral Anterior-Posterior Tears Associated With Acute Acromioclavicular Joint Separation of All Injury Grades

Background

Despite the relatively high number of cases of acromioclavicular joint (AC) separation in the athletic population, optimal clinical outcomes are not achieved in every case. Limited data exist regarding the prevalence of intra-articular glenohumeral pathologies (IAPs) associated with acute AC separation of all injury grades.

Purpose

To determine the prevalence of IAPs associated with AC separation, regardless of severity.

Study Design

Case series; Level of evidence, 4.

Methods

A total of 62 patients (mean age, 37.6 years) with acute AC separation were included in this study; 41 were nonoverhead recreational athletes. All patients underwent magnetic resonance arthrography (MRA) to evaluate for IAPs. Arthroscopic data from patients undergoing surgical treatment were correlated with MRA results.

Results

Patients sustained acute AC separation of Rockwood grade 1 (16.1%), grade 2 (46.8%), grade 3 (25.8%), and grade 4 (11.3%). A concomitant IAP was present in 48 of 62 (77.4%) patients and included superior labral anterior-posterior tears (72.6%), anterior labral tears (24.2%), posterior labral tears (4.8%), supraspinatus tears (3.2%), and inferior glenohumeral ligament ruptures (1.6%). There were 18 (29.0%) patients who had a concomitant pathology in >1 intra-articular structure (combined IAPs). Additionally, 71.8% of patients with grade 1 and 2 AC separation had associated IAPs, and 23.1% had combined IAPs. Furthermore, in patients younger than 40 years, 64.0% of those with grade 1 to 3 AC separation demonstrated associated labral pathologies. There was no difference when comparing age or severity of AC separation and the prevalence of concomitant labral tears (P = .36 and .22, respectively).

Conclusion

There was a high prevalence of IAPs among patients undergoing MRA after AC separation. While an IAP has been described in association with high-grade AC separation previously, the high prevalence of IAPs in low-grade separation in our study was unexpected and suggests that a thorough evaluation and clinical follow-up for patients with all grades of AC separation may be beneficial.

The Correlation of the SLAP II Lesion Findings Between Physical Examination, Magnetic Resonance Imaging, and Arthroscopic Surgery

OBJECTIVES

The aim of this study is to demonstrate the importance of clinical diagnosis by comparing with preoperative physical examination and magnetic resonance imaging (MRI) images in patients who were arthroscopically diagnosed as having Superior Labrum Anterior-Posterior (SLAP) II lesions.

MATERIALS AND METHODS

134 patients, arthroscopically diagnosed as SLAP II, established the study group, and 200 patients who underwent shoulder arthroscopy for the other pathologies established the control group. Preoperative clinical examination of the patients, MRI findings, and the arthroscopic findings of the patients were recorded.

RESULTS

Out of the patients diagnosed with a SLAP II lesion, 107 (79.9) of those had an MRI finding while only 60 (30%) of the control group had it. The O'Brien test results of the patients diagnosed with SLAP were positive in 111 (82.8%) while those diagnosed with intact superior labrum were positive in 132 (66%). Of the 134 patients with a SLAP II lesion, 89 (66.4%) had both O'Brien test positiveness and MRI finding, and 129 (96%) had at least one positive result of the O'Brien test or MRI examination.

CONCLUSION

The O'Brien test and MRI examination are not capable enough to indicate a SLAP lesion one by one, because of the low sensitivity and specificity. But, combining the test with MRI findings provides more trustable information about the superior labrum.

Magnetic resonance-guided direct shoulder arthrography for the detection of superior labrum anterior-posterior lesions using an open 1.0-T MRI scanner

Purpose

Direct magnetic resonance arthrography (MRA) offers increased diagnostic accuracy compared to conventional magnetic resonance imaging (MRI) in the detection of superior labrum anterior-posterior (SLAP) lesions. The aim of the present study was to present the technique of magnetic resonance-guided direct shoulder arthrography (MDSA), to evaluate the diagnostic value of this novel MRA procedure to detect SLAP lesions in comparison to the currently practiced MRI, and to correlate the radiological findings to the respective arthroscopic findings.

Material and methods

Fifty-six patients with clinical signs of a SLAP lesion underwent both MRI examination and MDSA prior to arthroscopic surgery. The MRI of both interventions were compared with the arthroscopic findings. Statistical analysis was performed using the McNemar test.

Results

Sensitivity, specificity, and accuracy for detecting SLAP lesions were 23%, 88%, and 54% on MRI and 80%, 81%, and 80% on MDSA, respectively. Sensitivity (p < 0.001) and accuracy (p = 0.001) in detection of SLAP lesions were significantly higher by MDSA whereas accuracy showed no significant differences (p = 0.625).

Conclusions

The MDSA can be performed in an open 1.0-T MRI scanner with a high level of technical success and a reasonable methodical effort. The modification of MRA provides the requirements as a practicable routine shoulder magnetic resonance examination including arthrography to detect SLAP lesions. The diagnostic value is significantly better than MRI examinations without included arthrography, which currently predominates the clinical practice to investigate shoulder pathology.

Incidence of gadolinium or fluid signal within surgically proven glenoid labral tears at MR arthrography

OBJECTIVE

To determine how often patients with surgically proven labral tears have labral signal on shoulder MR arthrography (MRA) that is not equal to gadolinium or fluid on T1- and T2-weighted images, respectively.

MATERIALS AND METHODS

Consecutive patients with surgical repair of a SLAP or Bankart labral tear within 95 days of an MRA were included. Using cartilage signal as an internal reference, two musculoskeletal (MSK) radiologists retrospectively categorized labral signal as T1-hyperintense, T1-gadolinium, T2-hyperintense, or T2-fluid. In patients without T1-gadolinium or T2-fluid labral signal, secondary findings such as the orientation, extent, shape, and width of the abnormal signal was recorded. Statistical analyses were performed using Fisher's test and ANOVA.

RESULTS

Sixty-one labral tears (36 SLAP and 25 Bankart) in 54 patients (mean age, 30.7; F:M 8:46) met the inclusion criteria. In 67% and 76% of SLAP and Bankart labral tears, T1-gadolinium signal was present (p = 0.43). T2-fluid signal was present in 50% and 92% of these same labral tears (p = 0.001). The absence of T1-gadolinium or T2-fluid signal was more common in SLAP tears (33%) compared to Bankart tears (8%) (p = 0.02). In the SLAP cases, at least two secondary findings of a SLAP tear were present in 92% (11/12).

CONCLUSIONS

Lack of surfacing T1-gadolinium or T2-fluid labral signal is unusual in Bankart tears but relatively common in SLAP tears. However, a SLAP tear was diagnosed in 92% of these 12 cases when two secondary findings were present.

Magnetic Resonance Arthrographic Demonstration of Association of Superior Labrum Anterior and Posterior Lesions With Extended Anterior Labral Tears

OBJECTIVE

The objective of this study was to evaluate retrospectively the full extent of anterior labral tear and associated other labral tears on magnetic resonance arthrographic images in patients with anterior shoulder instability.

MATERIALS AND METHODS

One hundred ten magnetic resonance arthrography images with anterior labral tear were retrieved from the database of the Radiology Department. Two skeletal radiologists, one with 15 years of experience and the other with 5 years of experience analyzed the images in random order. Approval for the study was granted by the Ethics Committee. Statistical analyses were performed using SPSS software.

RESULTS

The most common localization of the labral lesions was at the anterior-inferior part of the glenoid labrum (22.7%). The anterior labral tears were commonly associate with superior labrum anterior and posterior (SLAP) lesions (45%). The most common type of SLAP lesion was type V (23.6%). Superior Labrum Anterior and Posterior type V lesion was more often detected in patients with Bankart lesion (27.7%, P = 0.043).

CONCLUSIONS

Isolated anterior labral tears are less than expected. In majority of the cases, a distinct tear at a different site of the labrum accompanies the anterior labral tear. Massive anterior labral tears are mostly seen together with SLAP lesions.

Imaging the Glenoid Labrum and Labral Tears

The shoulder joint is the most unstable articulation in the entire human body. While this certainly introduces vulnerability to injury, it also confers the advantage of broad range of motion. There are many elements that work in combination to offset the inherent instability of the glenohumeral joint, but the glenoid labrum is perhaps related most often. Broadly, clinical unidirectional instability can be subdivided into anterior and posterior instability, which usually raise concern for anteroinferior and posteroinferior labral lesions, respectively. In the special case of superior labral damage, potential dislocation is blocked by structures that include the acromion; hence, while damage elsewhere commonly manifests as clinical instability, damage to the superior labrum is often described by the term microinstability. In this particular case, one of the radiologist's main concerns should be classic superior labral anteroposterior lesions. The glenoid labrum is also subject to a wide range of normal variants that can mimic labral tears. Knowledge of these variants is central to interpreting an imaging study of the labrum because misdiagnosis of labral variants as tears can lead to superfluous surgical procedures and decreased shoulder mobility. This article reviews labral anatomy and normal labral variants, describes their imaging features, and discusses how to discriminate normal variants from labral tears. Specific labral pathologic lesions are described per labral quadrant (anteroinferior, posteroinferior, and superior), and imaging features are described in detail. Online supplemental material is available for this article. ^©RSNA, 2016.

Outcomes in patients with glenoid labral lesions: a cohort study

BACKGROUND/AIM

For patients presenting with glenoid labral pathologies, there is little information on how operative interventions affect long-term outcomes and health-related quality of life (HRQoL). This study evaluated outcomes in operative and non-operative patients presenting with labral tears versus labral degenerations.

METHODS

Participants completed a pain Visual Analogue Scale (VAS), the Veterans RAND 12-item Health Survey, Western Ontario Rotator Cuff Index, American Shoulder and Elbow Surgeons instrument, Scapular Assistance Test (SAT), Shoulder Activity Level, and Single Assessment Numeric Evaluation at baseline and at 6-month, 12-month and 2-year follow-ups. χ²and Student's t-test were used to test the differences between categorical and continuous variables. Analysis of variance investigated the differences between groups, and linear regression analyses explored the relationship of baseline characteristics with outcome scores.

RESULTS

After 2 years, the operative cohort (n=68) significantly improved in all measures. The non-operative cohort (n=55) showed significant improvements in all scores except the mental component summary (MCS) and pain VAS. Labral tear patients (n=52) within the operative group (n=28) significantly improved in all measures except MCS. Non-operative labral tear patients (n=24) indicated significant improvements in all measures except MCS, VAS and SAT. Labral degeneration patients (n=71) within the operative group (n=27) significantly improved in all measures except MCS and SAT. Non-operative labral degeneration patients (n=44) indicated significant improvements in all measures except the physical component summary, MCS, VAS and SAT.

CONCLUSION

Patients who were surgically treated for labral tears or degenerations had significantly improved outcomes and HRQoL scores after 2 years compared with the non-operative cohort.

What are the anatomical predictive factors of degenerative superior labrum anterior to posterior lesion in rotator cuff tear?

The purpose of this study was to evaluate the influence of anatomical factors degenerative superior labrum anterior to posterior lesion in rotator cuff tear. The study included 421 middle-aged patients treated using arthroscopic surgery for rotator cuff tears. Patients were divided into two groups based on the superior labrum anterior-to-posterior (SLAP). Glenoid inclination, glenoid length, humeral head diameter, acromio-humeral distance (AHD) head-glenoid difference (HGD), head glenoid angle (HGA), size and retraction of rotator cuff tears were evaluated in both groups. In conclusion, a HGD exceeding 10 mm could be anatomically predictive of degenerative SLAP.

LEVEL OF EVIDENCE

Case series, Level IV.

Diagnosis of Superior Labrum Anterior-to-Posterior Tears by Using MR Imaging and MR Arthrography: A Systematic Review and Meta-Analysis

Purpose To evaluate the diagnostic accuracies of nonenhanced magnetic resonance (MR) imaging and MR arthrography for diagnosis of superior labrum anterior-to-posterior (SLAP) tears by using a systematic review and meta-analysis. Materials and Methods A comprehensive literature search was performed on the two main concepts of MR imaging (MR imaging, and direct and indirect MR arthrography) and SLAP tears. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR imaging, direct MR arthrography, and/or indirect MR arthrography for the detection of SLAP tears, by using surgical findings as the reference standard. The Quality Assessment of Diagnostic Accuracy Studies 2, or QUADAS-2 Quality Assessment of Diagnostic Accuracy Studies 2 Quality Assessment of Diagnostic Accuracy Studies 2 , tool was used to assess methodologic quality. Meta-analyses were performed that compared MR imaging studies to direct MR arthrography studies and indirect MR arthrography studies, 3-T studies to 1.5-T studies, and low-bias MR imaging studies to low-bias direct MR arthrography studies. Study variation was analyzed by using the Cochran Q test of heterogeneity and the I² statistic. Results Thirty-two studies met inclusion and exclusion criteria, including 3524 imaging examinations: 1963 direct MR arthrography examinations (23 studies), 1402 MR examinations (14 studies), and 159 indirect MR arthrography examinations (three studies). Twelve studies had low risk for bias, two had questionable risk, and 18 had high risk. Mean sensitivities of direct MR arthrography, MR imaging, and indirect MR arthrography for SLAP tear diagnosis were 80.4%, 63.0%, and 74.2%, respectively. Mean specificities of direct MR arthrography, MR imaging, and indirect MR arthrography were 90.7%, 87.2%, and 66.5%, respectively. Summary receiver operator characteristic (ROC) curve demonstrated superior accuracy of direct MR arthrography compared with those of MR imaging and indirect MR arthrography. Similar findings were observed in the low-bias subanalysis. Summary ROC curve demonstrated overall superiority of 3-T imaging, with or without intra-articular contrast material compared with 1.5-T imaging, with or without intra-articular contrast material. Significant variance was observed for MR imaging and direct MR arthrography (P < .001) studies for both mean sensitivity and specificity. Conclusion Direct MR arthrography appears to be more accurate than nonenhanced MR imaging for diagnosis of SLAP tears, whereas 3-T MR imaging with or without intra-articular contrast material appears to improve diagnostic accuracy compared with 1.5-T MR imaging with or without intra-articular contrast material. ^© RSNA, 2017 Online supplemental material is available for this article.

Unclassified MR arthrography pattern evaluation in patients with episodes of recurrent antero-inferior shoulder dislocation

PURPOSE

To evaluate prospectively the incidence of unclassifiable MR arthrography patterns of glenoid anterior-inferior labrum lesions, in patients with at least two episodes of recurrent antero-inferior shoulder dislocation.

MATERIALS AND METHODS

The MR shoulder Arthrography images of 36 patients, with at least two episodes of recurrent antero-inferior dislocation, were prospectively evaluated, during a period between November 2015 and Mai 2016. All patients were contacted after 6 months of the MR arthrography to evaluate their course of treatment. The MR arthrography images were analyzed by two radiologists, respectively with 5 and 15 years of experience in musculoskeletal radiology.

RESULTS

36 cases of unclassifiable MR arthrography pattern of the anterior-inferior glenoid labrum were evaluated: in 13 out 36 cases (36.1%), the glenoid labrum has been described as "oedematous and swollen"; in 19 out 36 cases (52.8%), it has been described as "smooth" (not hypoplastic); in 4 out 36 cases (11.1%), it has been described as degenerated.

CONCLUSION

The unclassifiable MR arthrography patterns of fibrocartilage glenoid lesions after episodes of recurrent antero-inferior dislocation are commons. The unclassifiable MR arthrography patterns require a careful consideration, in order to improve the diagnostic and therapeutic multidisciplinary approach.

A systematic review and meta-analysis of diagnostic test of MRA versus MRI for detection superior labrum anterior to posterior lesions type II-VII

OBJECTIVE

To determine the diagnostic performance of magnetic resonance arthrography (MRA) and magnetic resonance imaging (MRI) in superior labrum anterior to posterior lesions (type II-VII) of the shoulder.

MATERIAL AND METHODS

PubMed and Scopus search engines, an electronic search of articles was performed from inception to February 19, 2016. Diagnostic performance of index tests was compared by the summary area under receiver operator characteristic curve (AUROC).

RESULTS AND CONCLUSIONS

In all, 117 of 493 studies were eligible and 32 studies (2,013 shoulders) and 11 studies (1,498 shoulders) were evaluated with MRA and MRI. The summary sensitivity, specificity, likelihood ratio (positive and negative) and AUROC were 0.87 (95 % confidence interval, CI: 0.82, 0.91), 0.92 (95 %CI: 0.85, 0.95), 10.28 (95 %CI: 5.84, 18.08), 0.14 (95 %CI: 0.10, 0.20) and 0.94 (95 %CI: 0.92, 0.96) respectively for MRA, and 0.76 (95 %CI: 0.61, 0.86), 0.87 (95 %CI: 0.71, 0.95), 5.89 (95 %CI: 2.5, 13.86), 0.28 (95 %CI: 0.17, 0.47) and 0.94 (95 %CI: 0.92, 0.96) respectively for MRI. The diagnostic performance of MRA was superior to MRI by both direct and indirect comparisons for the detection of SLAP lesions.

Reliability of magnetic resonance imaging versus arthroscopy for the diagnosis and classification of superior glenoid labrum anterior to posterior lesions

PURPOSE

The physical examination of the shoulder is usually not reliable for the true diagnosis of superior glenoid labrum anterior to posterior (SLAP) lesions. Magnetic resonance imaging (MRI) has been routinely used for the diagnosis. This prospective study investigates the radiological diagnosis of the SLAP lesions and compares accuracy of arthroscopic and MRI classifications.

METHODS

One hundred thirty-two patients with positive physical examination signs using O'Brien, Yergason, resistance supination external rotation and Krank tests and MRI findings are included in the study. Shoulder MRIs were obtained for all patients within three months prior to the surgeries. SLAP lesion is detected in 90 and 102 patients according to MRI and arthroscopy, respectively. Arthroscopic and MRI classifications of the patients were performed according to modified Snyder classification.

RESULTS

Sensitivity and specificity of the MRI were found as 70.59 and 40%, respectively. No difference was detected between MRI and arthroscopy classifications in 52 (39%) patients. Although the diagnosis was compatible with arthroscopy in 34 (25%) patients, the classification was incompatible. In 46 (34%) of patients the diagnosis was incompatible with the MRI.

CONCLUSION

Although MRI is a good diagnostic tool for SLAP lesions, its use for the classification is limited. Level of evidence Level III, Diagnostic study.

What can the Radiologist do to Help the Surgeon Manage Shoulder Instability?

Imaging of the shoulder forms an important adjunct in clinical decision making in patients with shoulder instability. The typical lesions related with classic anterior and anteroinferior shoulder dislocation are an anteroinferior labral avulsion with or without bony fragment of bone loss – a (bony) Bankart lesion – and a posterolateral humeral head impaction fracture – the Hill-Sachs lesions. These are relatively straightforward to identify on imaging, although normal variants of the inferior labrum and variants of labral damage may cause confusion. Other capsuloligamentous lesions, often associated with less typical types of instability, are much more difficult to identify correctly on imaging, as they occur in the anterosuperior part of the glenohumeral joint with its many normal variants or because they result in more subtle, and therefore easily overlooked, changes in morphology or signal intensity. This paper aims at describing the appearance of the normal and pathologic glenohumeral joint related to shoulder instability. Ample reference will be given as to why identification of abnormalities, whether normal or pathologic, is important to the surgeon facing a treatment decision.

Magnetic resonance imaging evaluation of meniscoid superior labrum: normal variant or superior labral tear

Objective

The objective of this study was to determine the incidence of a "meniscoid" superior labrum.

Materials and Methods

This was a retrospective analysis of 582 magnetic resonance imaging examinations of shoulders. Of those 582 examinations, 110 were excluded, for a variety of reasons, and the final analysis therefore included 472 cases. Consensus readings were performed by three musculoskeletal radiologists using specific criteria to diagnose meniscoid labra.

Results

A meniscoid superior labrum was identified in 48 (10.2%) of the 472 cases evaluated. Arthroscopic proof was available in 21 cases (43.8%). In 10 (47.6%) of those 21 cases, the operative report did not include the mention a superior labral tear, thus suggesting the presence of a meniscoid labrum. In only one of those cases were there specific comments about a mobile superior labrum (i.e., meniscoid labrum). In the remaining 11 (52.4%), surgical correlation demonstrated superior labral tears.

Conclusion

A meniscoid superior labrum is not an infrequent finding. Depending upon assumptions and the requirement of surgical proof, the prevalence of a meniscoid superior labrum in this study was between 2.1% (surgically proven) and 4.8% (projected). However, superior labral tears are just as common and are often confused with meniscoid labra.

Pathomechanics and Magnetic Resonance Imaging of the Thrower's Shoulder

Repetitive, high-velocity overhead throwing can lead to several adaptive changes in the throwing shoulder, which over time lead to structural microtrauma and eventually overt injury. MR imaging is a useful imaging modality to evaluate these changes and to characterize their acuity and severity. Understanding the throwing motion and the effects of this motion on the structures of the shoulder can help radiologists to recognize these findings and provide useful information to referring physicians, which may affect the treatment of these athletes. This article reviews shoulder pathomechanics and MR imaging findings in overhead throwing athletes.

Magnetic Resonance Arthrogram Referrals by Subspecialist and Non-Subspecialist Orthopaedic Surgeons: What are the Findings?

Background:

Although subspecialist orthopaedic surgeons usually request Magnetic Resonance Arthrogram (MRA) examinations, some orthopaedic surgeons may request this examination for a body part that is different from their subspecialty. The purpose of the study is to compare the MRA and the clinical findings in the subspecialist and non-subspecialist groups.

Method:

Retrospective analysis of MRA examinations over a 6-month period. Findings were compared with the clinical information.

Results:

There were 144 examinations (69 shoulder, 42 wrist and 33 hip). 85% of these were subspecialist referrals; 60% of them showed findings compatible with the clinical diagnosis. 15% of the MRA examinations were non-subspecialist referrals; 52% of them correlated with the clinical findings.

Overall, clinical information agreed with MRA findings for shoulder labral tears, hip labral tears and wrist triangular fibrocartilage complex tears in 63.3%, 64.5% and 61.5% respectively. The subspecialist group were more accurate than the non-subspecialist group in diagnosing hip labral tears (68% vs. 50%) and triangular fibrocartilage complex tears (62.5% vs. 50%). On the contrary, shoulder MRA and clinical findings correlated better in the non-subspecialist group (77.8%) compared to the subspecialist group (63.3%). However, the small number of requests generated by the non-subspecialist group may affect the results. Suspected scapholunate ligament injury showed low correlation with MRA at 26.7% (33.3% in the subspecialist group and 0% in the non-subspecialist group).

Conclusion:

Generally, the clinical findings are more accurate in the subspecialist referrals when compared to MRA findings and therefore a subspecialist referral is preferred. The low agreement between clinically suspected scapholunate ligament injuries and wrist MRA probably reflects the relative difficulty in establishing this diagnosis clinically.

Beyond the Cuff: MR Imaging of Labroligamentous Injuries in the Athletic Shoulder

Shoulder disease is common in the athletic population and may arise as a consequence of a single traumatic episode or multiple repeated events. Associated labroligamentous injuries can result in substantial disability. Specific athletic and occupational activities result in predictable injury patterns. Imaging in general and magnetic resonance (MR) imaging, in particular, are vital in establishing the correct diagnosis and excluding common mimicking conditions, to ensure timely and appropriate management. In this review, the utility of MR imaging and MR arthrography will be explored in evaluation of shoulder disease, taking into account normal variants of the labroligamentous complex. Subsequently, broad categories of labral lesions and instability, external and internal impingement, as well as nerve entrapment syndromes, will be discussed, while emphasizing their imaging findings in the clinical context and illustrating key features. More recent concepts of internal impingement and secondary subacromial impingement will also be clarified.

Magnetic Resonance Imaging Currently Fails to Fully Evaluate the Biceps-Labrum Complex and Bicipital Tunnel

PURPOSE

To determine the diagnostic accuracy of magnetic resonance imaging (MRI) for biceps-labrum complex (BLC) lesions, including the extra-articular bicipital tunnel.

METHODS

A retrospective review of 277 shoulders with chronic refractory BLC symptoms that underwent arthroscopic subdeltoid transfer of the long head of the biceps tendon (LHBT) to the conjoint tendon was conducted. Intraoperative lesions were categorized as "inside" (labral tears and dynamic LHBT incarceration), "junctional" (LHBT partial tears, LHBT subluxation, and biceps chondromalacia), or "bicipital tunnel" (extra-articular bicipital tunnel scar/stenosis, loose bodies, LHBT instability, and LHBT partial tears) based on anatomic location. Attending radiologist-generated MRI reports were graded dichotomously as positive or negative for biceps and labral damage and then compared with intraoperative findings. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for MRI with respect to intraoperative findings.

RESULTS

With regard to inside lesions, MRI had an overall sensitivity, specificity, PPV, and NPV for labrum lesions of 77.3%, 68.2%, 57.3%, and 84.5% respectively. The sensitivity, specificity, PPV, and NPV of MRI for junctional lesions were 43.3%, 55.6%, 73.1%, and 26.0%, respectively. For the bicipital tunnel, MRI had a sensitivity, specificity, PPV, and NPV of 50.4%, 61.4%, 48.7%, and 63.0%, respectively.

CONCLUSIONS

MRI was unreliable for ruling out BLC lesions among chronically symptomatic patients, including when the bicipital tunnel was affected.

High Prevalence of Superior Labral Tears Diagnosed by MRI in Middle-Aged Patients With Asymptomatic Shoulders

Background:

The incidence of superior labral surgery has increased in the past decade in the United States, and a contributing factor could be an increased rate of superior labral tears diagnosed with magnetic resonance imaging (MRI). Prior MRI studies of the asymptomatic shoulder have focused on rotator cuff pathology or pathology in a narrow and specific group of athletes. Labral abnormalities have not previously been thoroughly evaluated in asymptomatic middle-aged individuals.

Purpose:

To evaluate the prevalence of superior labral tears diagnosed by MRI in the asymptomatic shoulders of middle-aged people (age range, 45-60 years).

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A total of 53 asymptomatic adults (age range, 45-60 years) with no history of surgery or injury to either shoulder were included in the study. Physical examinations of all shoulders were performed. Noncontrast MRI (1.5 T) was performed in 1 randomly determined shoulder of each subject. Two fellowship-trained musculoskeletal radiologists who were blinded to the purpose of the study and ages of the subjects evaluated each MRI.

Results:

Radiologists interpreted the MRIs as consistent with superior labral tears in 55% and 72% of the cohort. Comparison of the radiological evaluations of the superior labra were moderate (κ = 0.410, P = .033). There were no differences in readings for superior labral tear regarding age (P = .87), sex (P = .41), whether the dominant shoulder underwent MRI (P = .99), whether the subject worked a physical job (P = .08), or whether the subject participated in overhead sports for a period of 1 year (P = .62).

Conclusion:

Superior labral tears are diagnosed with high frequency using MRI in 45- to 60-year-old individuals with asymptomatic shoulders. These shoulder MRI findings in middle-aged populations emphasize the need for supporting clinical judgment when making treatment decisions for this patient population.

Clinical Relevance:

To avoid overtreatment, physicians should realize that superior labral tears diagnosed by MRI in individuals between the ages of 45 and 60 years may be normal age-related findings.

TRANSLATION TO PORTUGUESE LANGUAGE AND CROSS-CULTURAL ADAPTATION OF THE MODIFIED ROWE SCORE FOR OVERHEAD ATHLETES

Objetctive: Study was to translate and culturally adapt the modified Rowe score for overhead athletes.

METHODS

The translation and cultural adaptation process initially involved the stages of translation, synthesis, back-translation, and revision by the Translation Group. It was than created the pre-final version of the questionnaire, being the areas "function" and "pain" applied to 20 athletes that perform overhead movements and that suffered SLAP lesions in the dominant shoulder and the areas "active compression test and anterior apprehension test" and "motion" were applied to 15 health professionals.

RESULTS

During the translation process there were made little modifications in the questionnaire in order to adapt it to Brazilian culture, without changing the semantics and the idiomatic concept originally described.

CONCLUSION

The questionnaire was easily understood by the subjects of the study, being possible to obtain the Brazilian version of the modified Rowe score for overhead athletes that underwent surgical treatment of the SLAP lesion.

High-Resolution Qualitative and Quantitative Magnetic Resonance Evaluation of the Glenoid Labrum

OBJECTIVE

This study aimed to implement qualitative and quantitative magnetic resonance sequences for the evaluation of labral pathology.

METHODS

Six glenoid labra were dissected, and the anterior and posterior portions were divided into normal, mildly degenerated, or severely degenerated groups using gross and magnetic resonance findings. Qualitative evaluation was performed using T1-weighted, proton density-weighted, spoiled gradient echo and ultrashort echo time (UTE) sequences. Quantitative evaluation included T2 and T1rho measurements as well as T1, T2*, and T1rho measurements acquired with UTE techniques.

RESULTS

Spoiled gradient echo and UTE sequences best demonstrated labral fiber structure. Degenerated labra had a tendency toward decreased T1 values, increased T2/T2* values, and increased T1rho values. T2* values obtained with the UTE sequence allowed for delineation among normal, mildly degenerated, and severely degenerated groups (P < 0.001).

CONCLUSIONS

Quantitative T2* measurements acquired with the UTE technique are useful for distinguishing among normal, mildly degenerated, and severely degenerated labra.

Accuracy of magnetic resonance imaging to diagnose superior labrum anterior-posterior tears

PURPOSE

The purpose of this study was to evaluate the accuracy of magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) in diagnosing superior labral anterior-posterior (SLAP) lesions. We hypothesized that the accuracy of MRI and MRA was lower than previously reported.

METHODS

Between 2006 and 2008, 444 patients who had both shoulder arthroscopy and an MRI (non-contrast or MR arthrography) for shoulder pain at our institution prior to surgery were identified and included in the study. The radiologic diagnosis and surgical evaluation were compared to determine the accuracy of diagnosing a SLAP lesion by MRI. Using arthroscopy as the standard, sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated for all MRIs, as well as separately for the non-intra-articular contrast MRI group and the MR arthrography group.

RESULTS

Of the 444 patients having an MRI and arthroscopy for shoulder pain, 121 had a SLAP diagnosis by MRI and 44 had a SLAP diagnosis by arthroscopy. Overall, MRI had an accuracy of 76 %, a PPV of 24 %, and a NPV of 95 %. Sensitivity was 66 %, and specificity was 77 %. MR arthrography had an accuracy of 69 %, sensitivity of 80 %, and a PPV of 29 %. Non-contrast MRI had an accuracy of 85 %, sensitivity of 36 %, and a PPV of 13 %.

CONCLUSIONS

In our retrospective study of 444 patients, sensitivity, specificity, and accuracy were all lower than previously reported in the literature for diagnosing SLAP lesions. Our data indicated that while MRI could exclude a SLAP lesion (NPV = 95 %), MRI alone was not an accurate clinical tool. MR arthrography had a large number of false-positive readings in this study. We concluded that even with intra-articular contrast, MRI had limitations in the ability to diagnose surgically proven SLAP lesions.

Arthroscopic repair of type II SLAP lesions: Clinical and anatomic follow-up

Aims:

The aim was to evaluate the clinical and anatomic outcome of arthroscopic repair of type II SLAP lesions.

Materials and Methods:

The senior author performed isolated repairs of 25 type II SLAP lesions in 25 patients with a mean age of 40.0 ± 12 years. All tears were repaired using standard arthroscopic suture anchor repair to bone. All patients were reviewed using a standardized clinical examination by a blinded, independent observer, and using several shoulder outcome measures. Patients were evaluated by magnetic resonance imaging arthrogram at a minimum of 1-year postoperatively.

Statistical Analysis Used:

Two-tailed paired t-test were used to determine significant differences in preoperative and postoperative clinical outcomes scores. In addition, a Fisher's exact test was used.

Results:

At a mean follow-up of 54-month, the mean American Shoulder and Elbow Surgeons Shoulder Index (ASES) scores improved from 52.1 preoperatively to 86.1 postoperatively (P < 0.0001) and the Simple Shoulder Test (SST) scores from 7.7 to 10.6 (P < 0.0002). Twenty-two out of the 25 patients (88%) stated that they would have surgery again. Of the 21 patients who had postoperative magnetic resonance imaging arthrographys (MRAs), 9 patients (43%) demonstrated dye tracking between the labrum bone interface suggestive of a recurrent tear and 12 patients (57%) had a completely intact repair. There was no significant difference in ASES, SST, and patient satisfaction scores in patients with recurrent or intact repairs.

Conclusions:

Arthroscopic repair of type II SLAP lesions demonstrated improvements in clinical outcomes. However, MRA imaging demonstrated 43% of patients with recurrent tears. MRA results do not necessarily correlate with clinical outcome.

Superior Labral Cleft after Superior Labral Anterior-to-Posterior Tear Repair: CT Arthrographic Features and Correlation with Clinical Outcome

PURPOSE

To evaluate the presence of a superior labral cleft at postoperative computed tomographic (CT) arthrography after superior labral anterior-to-posterior lesion (SLAP) repair and to correlate CT arthrographic appearance with clinical outcomes.

MATERIALS AND METHODS

The institutional review board approved this retrospective study, and the requirement to obtain informed consent was waived. Fifty-six patients who underwent CT arthrography after arthroscopic SLAP repair were included. Two musculoskeletal radiologists retrospectively reviewed CT arthrographic images for the presence, size, location, direction, and shape of a superior labral cleft, which was defined as a detectable contrast material-filled focal discontinuity of the labrum within anchor fixation sites of the glenoid. In addition, the glenoid osteolysis ratio was calculated on the basis of the CT arthrographic images. Clinical outcome was evaluated with use of the American Shoulder and Elbow Surgeons (ASES) scoring system. Continuous variables, such as patient age, interval between imaging and surgery, ASES score, and osteolysis ratio, were compared by using the Mann-Whitney U test.

RESULTS

A superior labral cleft was observed in 27 of the 56 patients (48%). The mean width and depth of the superior labral clefts was 2.1 mm ± 1.1 and 2.8 mm ± 0.8, respectively. The superior labral clefts extended posterior to the biceps anchor in 16 of the 27 patients (59%), were curved medially in 24 (89%), and had a smooth margin in 22 (81%). No significant association was observed between the presence of a superior labral cleft and the ASES score (P = .805) or patient age (P = .290). Superior labral clefts were observed more commonly in cases with a long interval since surgery (P = .007) and a high osteolysis ratio (P = .011).

CONCLUSION

Superior labral clefts are frequently observed on CT arthrographic images after arthroscopic SLAP repair and do not correlate with clinical outcome.

A comparison of magnetic resonance arthrography and arthroscopic findings in the assessment of anterior shoulder dislocations

OBJECTIVE

The aim of this study is to establish the sensitivity and specificity of MRA in the investigation of patients with traumatic anterior shoulder dislocations.

MATERIALS AND METHODS

A retrospective analysis of consecutive patients undergoing both magnetic resonance arthrography and arthroscopic assessment after a traumatic anterior shoulder dislocation between January 2011 and 2014 was performed. Demographic data were collected from electronic records. Images were interpreted by 8 musculoskeletal radiologists and patients were treated by 8 consultant orthopaedic surgeons. Arthroscopic findings were obtained from surgical notes and these findings were used as a reference for MRA. The sensitivity, specificity, and positive predictive value were calculated for the different injuries.

RESULTS

Sixty-nine patients underwent both an MRA and shoulder arthroscopy during the study period; however, clinical notes were unavailable in 9 patients. Fifty-three patients (88 %) were male, the mean age was 28 years (range 18 to 50) and 16 subjects (27 %) had suffered a primary dislocation. The overall sensitivity and specificity of MRA to all associated injuries was 0.9 (CI 0.83-0.95) and 0.94 (CI 0.9-0.96) retrospectively. The lowest sensitivity was seen in osseous Bankart 0.8 (CI 0.44-0.96) and superior labral tear (SLAP) lesions 0.5 (CI 0.14-0.86). The overall positive predictive value was 0.88 (CI 0.76-0.91) with the lowest values found in rotator cuff 0.4 (CI 0.07-0.83) and glenohumeral ligament (GHL) lesions 0.29 (CI 0.05-0.7).

CONCLUSION

Magnetic resonance angiography has a high sensitivity when used to identify associated injuries in shoulder dislocation, although in 8 patients (13 %) arthroscopy identified an additional injury. The overall agreement between MRA and arthroscopic findings was good, but the identification of GHL and rotator cuff injuries was poor.

Type 2 Superior Labral Anterior to Posterior Lesion-Related Paralabral Cyst Causing Isolated Infraspinatus Paralysis: Two Case Reports

Type 2 superior labral anterior to posterior (SLAP) lesion is a common cause of shoulder pain requiring surgical operation. SLAP tears are often associated with paralabral cysts, but they rarely cause nerve compression. However, we experienced two cases of type 2 SLAP-related paralabral cysts at the spinoglenoid notch which were confirmed as isolated nerve entrapment of the infraspinatus branch of the suprascapular nerve by electrodiagnostic assessment and magnetic resonance imaging. In these pathological conditions, comprehensive electrodiagnostic evaluation is warranted for confirmation of neuropathy, while surgical decompression of the paralabral cyst combined with SLAP repair is recommended.

Diagnostic performance of CT-arthrography and 1.5T MR-arthrography for the assessment of glenohumeral joint cartilage: a comparative study with arthroscopic correlation

PURPOSE

To compare the diagnostic performance of multi-detector CT arthrography (CTA) and 1.5-T MR arthrography (MRA) in detecting hyaline cartilage lesions of the shoulder, with arthroscopic correlation.

PATIENTS AND METHODS

CTA and MRA prospectively obtained in 56 consecutive patients following the same arthrographic procedure were independently evaluated for glenohumeral cartilage lesions (modified Outerbridge grade ≥2 and grade 4) by two musculoskeletal radiologists. The cartilage surface was divided in 18 anatomical areas. Arthroscopy was taken as the reference standard. Diagnostic performance of CTA and MRA was compared using ROC analysis. Interobserver and intraobserver agreement was determined by κ statistics.

RESULTS

Sensitivity and specificity of CTA varied from 46.4 to 82.4 % and from 89.0 to 95.9 % respectively; sensitivity and specificity of MRA varied from 31.9 to 66.2 % and from 91.1 to 97.5 % respectively. Diagnostic performance of CTA was statistically significantly better than MRA for both readers (all p ≤ 0.04). Interobserver agreement for the evaluation of cartilage lesions was substantial with CTA (κ = 0.63) and moderate with MRA (κ = 0.54). Intraobserver agreement was almost perfect with both CTA (κ = 0.94-0.95) and MRA (κ = 0.83-0.87).

CONCLUSION

The diagnostic performance of CTA and MRA for the detection of glenohumeral cartilage lesions is moderate, although statistically significantly better with CTA.

KEY POINTS

• CTA has moderate diagnostic performance for detecting glenohumeral cartilage substance loss. • MRA has moderate diagnostic performance for detecting glenohumeral cartilage substance loss. • CTA is more accurate than MRA for detecting cartilage substance loss.

Does the experience level of the radiologist, assessment in consensus, or the addition of the abduction and external rotation view improve the diagnostic reproducibility and accuracy of MRA of the shoulder?

AIM

To prospectively evaluate the influence of observer experience, consensus assessment, and abduction and external rotation (ABER) view on the diagnostic performance of magnetic resonance arthrography (MRA) in patients with traumatic anterior-shoulder instability (TASI).

MATERIALS AND METHODS

Fifty-eight MRA examinations (of which 51 had additional ABER views) were assessed by six radiologists (R1-R6) and three teams (T1-T3) with different experience levels, using a seven-lesion standardized scoring form. Forty-five out of 58 MRA examination findings were surgically confirmed. Kappa coefficients, sensitivity, specificity, and differences in percent agreement or correct diagnosis (p-value, McNemar's test) were calculated per lesion and overall per seven lesion types to assess diagnostic reproducibility and accuracy.

RESULTS

Overall kappa ranged from poor (k = 0.17) to moderate (k = 0.53), sensitivity from 30.6-63.5%, and specificity from 73.6-89.9%. Overall, the most experienced radiologists (R1-R2) and teams (T2-T3) agreed significantly more than the lesser experienced radiologists (R3-R4: p = 0.014, R5-R6; p = 0.018) and teams (T2-T3: p = 0.007). The most experienced radiologist (R1, R2, R3) and teams (T1, T2) were also consistently more accurate than the lesser experienced radiologists (R4, R5, R6) and team (T3). Significant differences were found between R1-R4 (p = 0.012), R3-R4 (p = 0.03), and T2-T3 (p = 0.014). The overall performance of consensus assessment was systematically higher than individual assessment. Significant differences were established between T1-T2 and radiologists R3-R4 (p<0.001, p = 0.001) and between T2 and R3 (p<0.001/p = 0.001) or R4 (p = 0.050). No overall significant differences were found between the radiologists' assessments with and without ABER.

CONCLUSION

The addition of ABER does not significantly improve overall diagnostic performance. The radiologist's experience level and consensus assessment do contribute to higher reproducibility and accuracy.

Subpectoral biceps tenodesis for the treatment of type II and IV superior labral anterior and posterior lesions

BACKGROUND

Surgical repair remains the gold standard for most type II and type IV superior labral anterior and posterior (SLAP) lesions that fail nonoperative management. However, most recently, there have been data demonstrating unacceptably high failure rates with primary repair of type II SLAP lesions. Biceps tenodesis may offer an acceptable, if not better, alternative to primary repair of SLAP lesions.

HYPOTHESIS

Subpectoral biceps tenodesis provides satisfactory, reproducible outcomes for the treatment of type II and type IV SLAP lesions.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent subpectoral biceps tenodesis and labral debridement for type II and type IV SLAP lesions by a single board-certified shoulder surgeon from 2006 to 2012 were evaluated. Exclusion criteria included those patients who underwent biceps tenodesis with an associated rotator cuff repair, anterior labral repair, or posterior labral repair. Outcome measures included the visual analog scale (VAS) for pain, the American Shoulder and Elbow Surgeons (ASES) score, and demographic data.

RESULTS

Between 2006 and 2012, a total of 36 subpectoral biceps tenodesis procedures were performed in 33 patients for type II or IV SLAP lesions. Twenty-six patients with 29 shoulder surgeries were available for follow-up. The average age was 46.7 years, with 16 male and 10 female patients participating in the study. The average follow-up was 40.17 months. There was a significant improvement in ASES and VAS scores: 48.1 and 6.4 preoperatively compared with 87.5 and 1.5 postoperatively, respectively (P < .001). There was no significant difference based on SLAP lesion type, patient age, or patient sex. Of 29 shoulders, 26 (89.66%) were able to return to the previous level of activity.

CONCLUSION

This study adds to the evolving literature supporting biceps tenodesis as a viable treatment for type II and IV SLAP lesions. Patient age had no effect on the outcomes. Based on these results, biceps tenodesis is a safe, effective, and technically straightforward alternative to primary SLAP repair in patients with type II and IV SLAP tears.

Analysis of Low-Field MRI Scanners for Evaluation of Shoulder Pathology Based on Arthroscopy

BACKGROUND

Many studies have compared the diagnostic capabilities of low-field magnetic resonance imaging (MRI) scanners to high-field MRI scanners; however, few have evaluated the low-field MRI diagnoses compared with intraoperative findings.

PURPOSE

To determine the accuracy and sensitivity of low-field MRI scanners in diagnosing lesions of the rotator cuff and glenoid labrum.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

Over a 2-year period, MRI examinations without intra-articular contrast were performed on 79 patients for shoulder pathologies using an in-office 0.2-T extremity scanner. The MRI examinations were read by board-certified, musculoskeletal fellowship-trained radiologists. All patients underwent shoulder arthroscopy performed by a single sports fellowship-trained orthopaedic surgeon within a mean time of 56 days (range, 8-188 days) after the MRI examination. The mean patient age was 54 years (range, 18-81 years). Operative notes from the shoulder arthroscopies were then retrospectively reviewed by a single blinded observer, and the intraoperative findings were compared with the MRI reports.

RESULTS

For partial-thickness rotator cuff tears, the sensitivity, specificity, positive predictive value, and negative predictive value were 85%, 89%, 79%, and 92%, respectively. For full-thickness rotator cuff tears, the respective values were 97%, 100%, 100%, and 98%. For anterior labral lesions, the values were 86%, 99%, 86%, and 99%, and for superior labral anterior-posterior (SLAP) lesions, the values were 20%, 100%, 100%, and 79%, respectively.

CONCLUSION

Low-field MRI is an accurate tool for evaluation of partial- and full-thickness rotator cuff tears; however, it is not effective in diagnosing SLAP lesions. More information is needed to properly assess its ability to diagnose anterior and posterior labral lesions.

The thrower's shoulder

Throwers, or athletes who engage in repetitive overhead motions, are a unique subset of athletes that experience distinct shoulder injuries. Athletes engaged in baseball comprise the majority of patients seeking orthopedic care for throwing related injuries. Injuries specific to throwers most commonly involve the labrum and the undersurface of the rotator cuff. In addition, tissue changes in both the anterior and posterior glenohumeral capsule are common with repetitive overhead motions. These capsular changes alter. This article will examine the pathomechanics of injuries to throwers, elaborate means of diagnoses of cuff and labral injury and discuss recent advances in both non-operative and operative interventions, including preventative principles.

Analysis of Low-Field Magnetic Resonance Imaging Scanners for Evaluation of Knee Pathology Based on Arthroscopy

Background:

In recent years, few studies have evaluated low-field magnetic resonance imaging (MRI) diagnoses compared with intraoperative findings of the knee.

Purpose:

To determine the accuracy and sensitivity of low-field MRI scanners in diagnosing pathology of the menisci, cruciate ligaments, and osteochondral surfaces.

Study Design:

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

Methods:

MRI examinations without intra-articular contrast were performed on 379 patients for knee pathologies over a 4-year period. The MRI examinations were done using a 0.2-tesla scanner utilizing a dedicated knee coil and read by 1 of 3 board-certified, musculoskeletal fellowship–trained radiologists. Within a mean time of 50 days after MRI, all patients underwent knee arthroscopy performed by 1 of 2 sports fellowship–trained orthopaedic surgeons. Operative notes from the knee arthroscopies were then reviewed by a single independent observer, and the intraoperative findings were compared with the MRI reports.

Results:

For medial meniscus tears, the sensitivity, specificity, positive predictive value, and negative predictive value were 83%, 81%, 89%, and 71%, respectively. For lateral meniscus tears, the values were 51%, 93%, 84%, and 73%, respectively. For anterior cruciate ligament (ACL) tears, the values were 85%, 94%, 69%, and 97%, respectively. For osteochondral lesions, the values were 8%, 99%, 29%, and 94%, respectively. For posterior cruciate ligament (PCL) tears, the specificity and negative predictive value were 99% and 100%, respectively.

Conclusion:

Low-field MRI was an accurate tool for evaluation of medial meniscus and ACL tears. However, within the study population, it is not as effective in diagnosing lateral meniscus tears and showed a poor ability to detect osteochondral lesions. More information is needed to properly assess its ability to diagnose PCL tears.

Diagnostic performance of magnetic resonance arthrography of the shoulder in children

BACKGROUND

No reported data demonstrate the usefulness of magnetic resonance arthrography of the shoulder in children.

OBJECTIVE

To evaluate the sensitivity, specificity and accuracy of MR arthrography in the assessment of superior labral anteroposterior (SLAP) tears of the shoulder, Bankart-type injuries and Hill-Sachs lesions in children as compared to arthroscopy.

MATERIALS AND METHODS

We retrospectively interpreted 66 MR arthrograms of the shoulder and compared them with surgical findings. Assessment included evaluation of the osseous structures, labral-ligamentous complex and determination of skeletal maturity. We calculated sensitivity, specificity and accuracy and compared sensitivity and specificity between skeletally mature and immature children.

RESULTS

MR arthrography demonstrated a sensitivity, specificity and accuracy of 88%, 98% and 94%, respectively, for depiction of SLAP tears; 94%, 92% and 94% for detection of Bankart-type injuries; and 100%, 94% and 97% for diagnosing Hill-Sachs lesions. There was no statistical difference between the skeletally immature and skeletally mature groups.

CONCLUSION

There is no significant difference in the diagnostic accuracy of MR arthrography in skeletally immature versus skeletally mature children. MR shoulder arthrography is an effective method for the detection of labral and bone pathology.

[Therapy relevant imaging in modern surgical treatment of arthrosis of the shoulder: interesting facts for orthopedic surgeons]

CLINICAL/METHODICAL ISSUE

Imaging for shoulder surgery varies a lot nowadays. Advantages and disadvantages of possible imaging methods according to the pathology and treatment options are described.

STANDARD RADIOLOGICAL METHODS

Digital projection radiography in 3 planes, ultrasonography, MRI, CT scanning and scintigrams.

METHODICAL INNOVATIONS

Special axial view to visualize the glenoid situation, as well as 3-D CT scanning for larger defects and classification.

PERFORMANCE

Imaging of the glenoid situation, the version and erosion in axial view x-ray is mandatory to plan and control glenoid replacement.

ACHIEVEMENTS

Useful application of imaging methods for the daily routine of orthopedic surgeons.

PRACTICAL RECOMMENDATIONS

Digital 3 plane x-ray imaging in arthroplasty surgery is the minimum requirement. For rotator cuff lesions ultrasonography is good. In order to gain information on fatty infiltration of rotator muscles MRI is needed as well as for intra-articular lesions. For bony defects CT and reconstruction 3-D are recommended.

Superior labral anterior posterior lesions of the shoulder

Superior labrum anterior and posterior (SLAP) lesion is of fairly recent description and its understanding is rapidly evolving. Its incidence and need for surgical treatment has increased exponentially in line with the increase in shoulder arthroscopies. It is of particular importance in the elite over head athlete and the young. A range of arthroscopic techniques and devices have been described with good functional results. The ability to return to pre injury level of sports remains a concern.

Diagnostic value of US, MR and MR arthrography in shoulder instability

INTRODUCTION

The aim of our study was to compare US, conventional MRI and MR arthrography findings in patients with anterior shoulder instability and with a clinical diagnosis of labral capsular ligamentous complex lesion. At the same time we evaluated the accuracy of MR arthrography in the diagnosis of this lesion.

METHODS

After approval of the local Ethics Committee, our department's Trauma Registry from July 2008 up to February 2012 was retrospectively reviewed to identify all eligible patients. Eligibility criteria included: 1)history of acute or chronic shoulder instability (more than three dislocations over a period of more than two months); 2) diagnosis of labroligamentous lesion. All patients were investigated with plain radiographs, Ultrasound Scans (US), Magnetic Resonance Imaging (MRI) and MR arthrography. Finally, all patients underwent an arthroscopy that confirmed the diagnosis.

RESULTS

A total of 200 consecutive patients who met the inclusion criteria were included in this study. The mean age was 39 years (range 15 to 83); 147 were male and 133 involved the right shoulder. Chronic instability was documented in 133 patients, whereas acute instability was documented in 67 patients. We detected a statistically significant difference between US and MR arthrography in SLAP (Superior Labrum Anterior to Posterior) lesions (TypeII, III and IV), in Bankart lesions, in glenohumeral ligament lesions (superior, middle, anterior-inferior and anterior inferior glenohumeral ligament) in Hill-Sachs lesions, in diagnosing internal subacromial impingement and in normal findings. MR arthrography was superior to the US. A statistically significant difference was evident between MRI and MR arthrography findings in SLAP lesions (III and IV Type lesions), in glenohumeral ligament lesions (anterior inferior and posterior inferior glenohumeral ligament), in partial rotator cuff ruptures and in normal findings. MR arthrography diagnosed this lesion better than MRI without contrast. We also found a statistically significant difference between US and MRI findings in SLAP Type II lesions, in partial rotator cuff ruptures, in Hill-Sachs lesions and in diagnosing internal subacromial impingement.

CONCLUSION

The US scan is a valuable diagnostic technique for rotator cuff complete or incomplete ruptures. For evaluating Hill-Sachs lesions or bony Bankart lesions, MRI is more accurate. In the case of labral capsular ligamentous complex lesions, MR arthrography is superior.

Arthroscopic reconstruction of shoulder's labrum with extensive tears

BACKGROUND

With the continuous development of arthroscopic techniques, the majority of superior labrum anterior-posterior (SLAP) lesions can be treated with minimally invasive endoscopic repair. The aim of this study was to determine the efficacy of arthroscopic capsulolabral reconstruction of SLAP lesions with extensive tears.

METHODS

Eighteen patients with SLAP lesions with extensive tears (median age, 27.50 years) were included in this study. Twelve patients had type-V SLAP lesions, 4 patients had type-VIII SLAP lesions, and 2 patients had deeply located SLAP lesions. The average duration of follow-up was 15.83 months (range, 11-22 months). Outcome measures included shoulder range of motion (ROM), American Shoulder and Elbow Surgeons (ASES) and Constant-Murley scores, and visual analogue scale (VAS) pain score.

RESULTS

After arthroscopic surgery, shoulder forward flexion, shoulder external rotation, and external rotation in 90° of abduction were significantly greater than before surgery (169.5° vs. 165.5°, P = 0.001), (90° vs. 63.5°, P < 0.001), and (90° vs. 81.5°, P = 0.004), respectively. Median ASES and Constant-Murley scores after surgery were both 94 as compared to 77.0 and 77.5, respectively, before surgery (both, P < 0.001). The median VAS score decreased to 1.5 after surgery as compared to 6 before surgery (P < 0.001).

CONCLUSIONS

Arthroscopic repair of SLAP lesions with extensive tears can achieve good outcomes.