Diagnosis of glenoid labral tears using 3-tesla MRI vs. 3-tesla MRA: a systematic review and meta-analysis

SECEC Didier Patte Prize 2023: the ABC classification of posterior shoulder instability

BACKGROUND

The ABC classification has recently been proposed as a comprehensive classification system for posterior shoulder instability (PSI). The purpose of this study was to analyze the comprehensiveness as well as inter-rater and intrarater reliability of the ABC classification.

METHODS

All consecutive patients presenting with unidirectional PSI from June 2019 to June 2021 were included in a prospective study. No patients were excluded, leaving a consecutive series of 100 cases of PSI in 91 patients. All recorded clinical and imaging data were used to create anonymized clinical case vignettes, which were evaluated twice according to the ABC classification at the end of the recruitment period in random sequential order by 4 independent raters (2 experienced shoulder surgeons and 2 orthopedic residents) to analyze the comprehensiveness as well as inter-rater and intrarater reliability of the ABC classification for PSI and to describe differences in characteristics among subtypes. Group A was defined as a first-time singular PSI event <3 months in the past regardless of etiology and is further subdivided into type 1 and type 2 depending on the occurrence of a subluxation (A1) or dislocation (A2). Group B comprises recurrent dynamic PSI regardless of time since onset and is further subdivided by the cause of instability into functional (B1) and structural (B2) dynamic PSI. Group C includes chronic static PSI with posterior humeral decentering that can be either constitutional (C1) or acquired (C2).

RESULTS

None of the cases was deemed unsuitable to be classified based on the proposed system by the observers. After consensus agreement between the 2 expert raters, 16 cases were attributed to group A (8 type A1 and 8 type A2); 64, to group B (33 type B1 and 31 type B2); and 20, to group C (11 type C1 and 9 type C2). The expert raters agreed on the classification subtypes in 99% and 96% of the cases during the first rating and second rating, respectively (intraclass correlation coefficients [ICCs], 0.998 and 0.99, respectively). The intraobserver reliability was excellent for both raters. The beginners reached the same conclusion as the consensus agreement in 94% of the cases (ICC, 0.99) and 89% of the cases (ICC, 0.97) during the first round and 94% each (ICC, 0.97) during the second round. The intraobserver reliability was excellent for both beginners. Overall, discrepancies between raters were found between groups B1 and B2 (n = 14), groups B2 and C2 (n = 4), groups B1 and C1 (n = 1), and groups A1 and B2 (n = 1). In general, each subtype showed distinctive clinical and imaging characteristics that facilitated the diagnosis.

CONCLUSION

The presented ABC classification for PSI is a comprehensive classification with a high reliability and reproducibility. However, a gradual transition and potential progression between the subtypes of PSI must be considered. The reliable distinction between different subtypes of PSI based on etiology and pathomechanism provides a standardized basis for future investigations on treatment recommendations.

Can the presence of SLAP-5 lesions be predicted by using the critical shoulder angle in traumatic anterior shoulder instability?

OBJECTIVE

Although SLAP-5 lesions are associated with recurrent dislocations, their causes and pathomechanisms have not been fully elucidated. This study aimed to investigate the association between SLAP-5 lesions and scapular morphology in traumatic anterior shoulder instability (ASI). We hypothesized that there may be a relationship between SLAP-5 lesions and scapular morphology in traumatic ASI patients.

MATERIALS AND METHODS

The study included 74 patients with isolated Bankart lesions and 69 with SLAP-5 lesions who underwent arthroscopic labral repair for ASI. Critical shoulder angle (CSA) was measured on the roentgenograms, while glenoid inclination (GI) and glenoid version (GV) were measured on magnetic resonance imaging (MRI) by two observers in two separate sessions blinded to each other. Both groups were compared in terms of CSA, GI, and GV.

RESULTS

The mean ages of Bankart and SLAP-5 patients were 28.4±9.1 and 27.9±7.7 (P=0.89), respectively; their mean CSA values were 33.1°±2.6° and 28.2°±2.4°, respectively (P<0.001). The ROC analysis's cut-off value was 30.5°, with 75.0% sensitivity and 76.7% specificity (AUC = 0.830). SLAP-5 lesions were more common on the dominant side than isolated Bankart lesions (P=0.021), but no difference was found between the groups in terms of GI and GV (P=0.334, P=0.081, respectively).

CONCLUSIONS

In ASI, low CSA values appeared to be related to SLAP-5 lesions, and the cut-off value of CSA for SLAP lesion formation was 30.5° with 75.0% sensitivity and 76.7% specificity. Scapula morphology may be related to the SLAP-5 lesions, and CSA can be used as an additional parameter in provocative diagnostic tests and medical imaging techniques for the detection of SLAP lesions accompanying Bankart lesions.

LEVEL OF EVIDENCE

III retrospective case-control study.

Radiographic and Advanced Imaging Evaluation of Posterior Shoulder Instability

PURPOSE OF REVIEW

Posterior shoulder instability is an uncommon but important cause of shoulder dysfunction and pain which may occur as the result of seizure, high energy trauma, or repetitive stress related to occupational or sport-specific activities. This current review details the imaging approach to the patient with posterior shoulder instability and describes commonly associated soft tissue and bony pathologies identified by radiographs, CT, and MR imaging.

RECENT FINDINGS

Advances in MR imaging technology and techniques allow for more accurate evaluation of bone and soft tissue pathology associated with posterior shoulder instability while sparing patients exposure to radiation. Imaging can contribute significantly to the clinical management of patients with posterior shoulder instability by demonstrating the extent of associated injuries and identifying predisposing anatomic conditions. Radiologic evaluation should be guided by clinical history and physical examination, beginning with radiographs followed by CT and/or MRI for assessment of osseous and soft tissue pathology. Synthesis of a patient's clinical history, physical exam findings, and radiologic examinations should guide clinical management.

[Shoulder-clinical introduction]

BACKGROUND

Radiological imaging plays a significant role in the diagnostics of shoulder pathologies. Based on a patient's medical history, physical examination and radiological imaging, it is possible to plan the further conservative or surgical treatment.

OBJECTIVES

Common pathologies of the shoulder and the correct radiological imaging are presented.

CONCLUSIONS

A rational and targeted use of radiological imaging, together with the medical history and physical examination allows correct diagnosis of pathologies of the shoulder joint.

SSR white paper: guidelines for utilization and performance of direct MR arthrography

OBJECTIVE

Direct magnetic resonance arthrography (dMRA) is often considered the most accurate imaging modality for the evaluation of intra-articular structures, but utilization and performance vary widely without consensus. The purpose of this white paper is to develop consensus recommendations on behalf of the Society of Skeletal Radiology (SSR) based on published literature and expert opinion.

MATERIALS AND METHODS

The Standards and Guidelines Committee of the SSR identified guidelines for utilization and performance of dMRA as an important topic for study and invited all SSR members with expertise and interest to volunteer for the white paper panel. This panel was tasked with determining an outline, reviewing the relevant literature, preparing a written document summarizing the issues and controversies, and providing recommendations.

RESULTS

Twelve SSR members with expertise in dMRA formed the ad hoc white paper authorship committee. The published literature on dMRA was reviewed and summarized, focusing on clinical indications, technical considerations, safety, imaging protocols, complications, controversies, and gaps in knowledge. Recommendations for the utilization and performance of dMRA in the shoulder, elbow, wrist, hip, knee, and ankle/foot regions were developed in group consensus.

CONCLUSION

Although direct MR arthrography has been previously used for a wide variety of clinical indications, the authorship panel recommends more selective application of this minimally invasive procedure. At present, direct MR arthrography remains an important procedure in the armamentarium of the musculoskeletal radiologist and is especially valuable when conventional MRI is indeterminant or results are discrepant with clinical evaluation.

Occult, Incomplete, and Complete Posterior Labral Tears Without Glenohumeral Instability on Imaging Underestimate Labral Detachment

PURPOSE

To introduce a classification of posterior labral tear and describe clinical characteristics, magnetic resonance imaging (MRI)/magnetic resonance arthrography (MRA) findings, arthroscopic findings, and outcomes after arthroscopic repair for patients with posterior labral tears without glenohumeral instability.

METHODS

Sixty patients with posterior labral tear who underwent arthroscopic repair were analyzed retrospectively. Patients with shoulder instability were excluded. Tear patterns were classified into 3 types; occult (type 1), incomplete (type 2), and complete (type 3) based on MRI/MRA studies. A visual analog scale score for pain, American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation score for satisfaction, and return to sports were evaluated at a minimum follow-up of 2 years. Computed tomography arthrography was performed at a year follow-up for assess labral healing. The diagnosis was confirmed in arthroscopy, and arthroscopic labral repair without capsular plication was performed.

RESULTS

The mean patient age was 30.4 ± 6.9 years, and all patients were male. Forty-four patients (73.3%) were participating in sports. MRI/MRA studies identified 10 patients with type 1, 18 with type 2, and 32 with type 3 tears. Type 1 tear patients showed a significantly longer symptom duration than those with type 3 (32.5 ± 17.2 vs 18.2 ± 17.1 months; P = .015). In arthroscopic findings, 70% of type 1 tear was confirmed as incomplete or complete tears. The American Shoulder and Elbow Surgeons score improved from 79.6 ± 10.3 to 98.1 ± 3.7, and pain was relieved from 2.4 ± 0.7 to 0.2 ± 0.5 at the last follow-up visit with high labral healing rate (95%). Thirty-nine (88.6%) patients returned to sports at preinjury levels.

CONCLUSIONS

In active young men with shoulder pain during daily activities or sports despite programmed conservative treatment, posterior labral tears should be considered even when MRI/MRA findings are ambiguous. Arthroscopic posterior labral repair without capsular plication provided satisfactory clinical outcomes and a high labral healing rate.

LEVEL OF EVIDENCE

Level Ⅳ, case series.

Physical Examination Maneuvers for SLAP Lesions: A Systematic Review and Meta-analysis of Individual and Combinations of Maneuvers

BACKGROUND

Superior labrum anterior to posterior (SLAP) lesions are targeted on physical examination using a variety of provocative maneuvers.

PURPOSE/HYPOTHESIS

The purpose was to conduct a systematic review on the performance of physical examination maneuvers in diagnosing SLAP lesions and to perform a meta-analysis comparing the sensitivity and specificity of these examinations both individually and in combination. The null hypothesis stated that there would be no significant difference in the sensitivity or specificity of the included physical examination tests, neither individually nor in combination.

STUDY DESIGN

Meta-analysis and systematic review; Level of evidence, 4.

METHODS

A systematic review was performed with the inclusion criteria of studies that reported either the sensitivities and specificities or the number of true-positive, true-negative, false-positive, or false-negative results for at least 1 maneuver for identifying SLAP lesions. A meta-analysis was performed to determine the sensitivity and specificity of individual maneuvers. Additional analysis determined the performance of these maneuvers when combined in series and parallel. In series, all must be present to be considered positive. In parallel, any single positive test forces the overall combination to be considered positive. Only tests that were included in ≥3 studies were considered in the meta-analysis and those included in ≥4 studies were considered in the combination analysis.

RESULTS

Overall, 862 studies were identified, 18 of which were included in the systematic review and meta-analysis. The physical examinations included were the O'Brien (n = 16), speed (n = 8), Yergason (n = 6), anterior slide (n = 8), crank (n = 7), Jobe (n = 5), dynamic labral shear (n = 3), Kim 2 (n = 3), and biceps groove tenderness tests (n = 3). All combinations of 2 to 5 maneuvers in both series and parallel were considered. The O'Brien and crank test combination was the most sensitive 2-test combination in both parallel and series. The Yergason and anterior slide test combination was the most specific 2-test combination in parallel and series.

CONCLUSION

This systematic review and meta-analysis reports an updated meta-analysis considering the sensitivity and specificity of common physical examination maneuvers used in the diagnosis of SLAP lesions and considers these values for tests in both series and parallel combinations. The present analysis demonstrates improved specificities when tests are considered in series and improved sensitivities when considered in parallel combination.

ABER Position in Direct MR Arthrography of the Shoulder: Useful Adjunct or Waste of Imaging Time?

PURPOSE

The usefulness of direct MR arthrography of the shoulder with additional ABER position (ABER-MRA) has always been discussed. The goals of the following review are to analyze the usefulness of this technique according to the available literature and present recommendations with respect to indications and benefits in diagnostic imaging of shoulder abnormalities in the clinical routine.

METHOD

For this review we assessed the current literature databases of the Cochrane Library, Embase, and PubMed with regard to MRA in the ABER position up to the February 28, 2022. Search terms were "shoulder MRA, ABER", "MRI ABER", "MR ABER", "shoulder, abduction external rotation MRA", "abduction external rotation MRI" and "ABER position". The inclusion criteria were prospective and retrospective studies with surgical and/or arthroscopic correlation within 12 months. Overall, 16 studies with 724 patients fulfilled the inclusion criteria: 10 studies dealing with anterior instabilities, three studies with posterior instabilities and seven studies with suspected rotator cuff pathologies (some studies addressing multiple items).

RESULTS

For anterior instability the use of ABER-MRA in the ABER position led to a significant increase in sensitivity for detecting lesions of the labral ligamentous complex compared with standard 3-plane shoulder MRA (81 % versus 92 %, p = 0.001) while maintaining high specificity (96 %). ABER-MRA demonstrated high sensitivity and specificity (89 % and 100 %, respectively) for SLAP lesions and was able to detect micro-instability in overhead athletes, but case counts are still very small. With regard to rotator cuff tears, no improvement of sensitivity or specificity could be shown with use of ABER-MRA.

CONCLUSION

Based on the currently available literature, ABER-MRA achieves a level of evidence C in the detection of pathologies of the anteroinferior labroligamentous complex. With regard to the evaluation of SLAP lesions and the exact determination of the degree of rotator cuff injury, ABER-MRA can be of additive value, but is still a case-by-case decision.

KEY POINTS

· ABER-MRA is useful in the evaluation of pathologies of the anteroinferior labroligamentous complex. · ABER-MRA does not increase sensitivity or specificity with regard to rotator cuff tears. · ABER-MRA may be helpful for the detection of SLAP lesions and micro-instability in overhead athletes.

CITATION FORMAT

· Altmann S, Jungmann F, Emrich T et al. ABER Position in Direct MR Arthrography of the Shoulder: Useful Adjunct or Waste of Imaging Time?. Fortschr Röntgenstr 2023; 195: 586 - 595.

ACR Appropriateness Criteria® Chronic Shoulder Pain: 2022 Update

Chronic shoulder pain is an extremely common presenting complaint. Potential pain generators include the rotator cuff tendons, biceps tendon, labrum, glenohumeral articular cartilage, acromioclavicular joint, bones, suprascapular and axillary nerves, and the joint capsule/synovium. Radiographs are typically the initial imaging study obtained in patients with chronic shoulder pain. Further imaging may often be required, with modality chosen based on patient symptoms and physical examination findings, which may lead the clinician to suspect a specific pain generator. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

[Sports injuries : What type of imaging is required?]

BACKGROUND

Imaging is of great importance in sports injuries, since the indication for conservative and surgical therapy depends on precise knowledge of the extent of the damage.

OBJECTIVES

Typical sports injuries and their imaging requirements are to be presented as examples.

CONCLUSIONS

In order to detect the often subtle pathologies, imaging must be adapted to the clinical diagnosis that is specifically suspected.

Diagnostic performance of MRA in abduction and external rotation position in the detection of glenoid labral lesions: a systematic review and meta-analysis

OBJECTIVE

To compare the diagnostic performance of direct magnetic resonance arthrography (MRA) for labral lesions during conventional, abduction and external rotation (ABER), conventional plus abduction, and external rotation (ABER) positioning by using a systematic review and meta-analysis.

MATERIALS AND METHODS

A comprehensive literature search was performed on the two main concepts of magnetic resonance arthrography: extremity position and labral lesions. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR arthrography in ABER and conventional position alone or combined for the diagnosis of labral lesions by using surgical findings as the reference standard. Meta-analyses were performed that compared MR arthrography during conventional positioning, ABER, and conventional plus ABER positioning.

RESULTS

Nine studies met the inclusion and exclusion criteria. A total of 733, 504, and 313 lesions assessed by conventional MRA, ABER MRA, and conventional plus ABER MRA, respectively, were included in our analysis. Pooled sensitivities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 81.5%, 81.6%, and 95.7%, respectively. Pooled specificities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 88.8%, 85.6%, and 94.5%, respectively. Summary receiver operator characteristic (ROC) curve demonstrated improved accuracy of conventional plus ABER MRA compared with conventional MRA or ABER MRA with the area under the curve (AUC) of 0.99, 0.90, and 0.88, respectively.

CONCLUSION

Conventional plus ABER MRA showed increased diagnostic accuracy compared to both ABER MRA and conventional MRA alone in the diagnosis of labral lesions.

The Use of Multiple Imaging Studies Before Shoulder Stabilization Surgery Is Increasing

Purpose

To determine the incidence of preoperative shoulder imaging, explore the prevalence of obtaining multiple advanced imaging studies, and identify patient characteristics associated with specific imaging studies before anterior versus posterior shoulder stabilization surgery.

Methods

The PearlDiver database was queried for patients who underwent anterior or posterior shoulder stabilization surgery from 2010 to 2019. The incidence of imaging studies within a year of surgery was collected. Patient characteristics were compared between groups using one-way analysis of variance or χ² test.

Results

In total, 10,252 patients underwent anterior shoulder stabilization surgery, and 1,108 patients underwent posterior shoulder stabilization surgery. Imaging use before anterior and posterior shoulder stabilization surgery included plain radiographs (69%, 70%, respectively), magnetic resonance imaging (MRI; 43%, 33%), and computed tomography (CT; 22%, 22%). In total, 1,098 patients (11%) received MRI and CT before anterior stabilization surgery and 85 patients (8%) received MRI and CT before posterior stabilization surgery. Over time, the incidence of obtaining MRI and CT increased before anterior (z = 2.54, P = .011) and posterior (z = 2.36, P = .018) stabilization surgery.

Conclusions

This study highlights the increasing use of multiple imaging studies before shoulder stabilization surgery over recent years, including plain radiographs, MRI, and CT imaging. In total, 45% of anterior shoulder stabilization patients and 41% of posterior shoulder stabilization patients obtained more than 1 imaging study within a year of surgery, with a recent increase in patients obtaining both MR and CT scans preoperatively.

Statement of Clinical Relevance

The increasing use of multiple preoperative imaging studies observed in this study highlights an opportunity for new imaging technology to streamline and improve the preoperative workup.

Clinical outcomes of Gaelic Athletic Association athletes after surgical stabilization in the setting of anterior shoulder instability

Background

Gaelic Athletic Association (GAA) games are collision sports played at an amateur level, which represent the most popular sports played on the island of Ireland. Each year, many GAA players in Ireland require surgical stabilization with either arthroscopic Bankart repair (ABR) or open Latarjet (OL) procedures in the setting of anterior shoulder instability. The purpose of this study was to evaluate the clinical outcomes, recurrence, and return to play (RTP) in athletes who play GAA games having undergone surgical stabilization with either ABR or OL procedures in the setting of anterior shoulder instability.

Methods

A retrospective review of all patients with anterior shoulder instability whom had stabilization with either ABR or OL under a single surgeon between 2012 and 2018 was performed. Patients who were athletes partaking in GAA sports were followed up by chart review and telephone survey to assess their clinical outcomes including satisfaction, pain as measured on the visual analog scale score, the Subjective Shoulder Value, recurrence, complications, and revision surgeries. In addition, RTP rates, time to RTP, level of RTP, and Shoulder Instability–Return to Sport after Injury scores were evaluated.

Results

A total of 200 GAA athletes (194 males) with a mean age of 23.9 ± 6.1 years with mean follow-up of 50.4 ± 24 months were included in this study. A total of 98.1% patients were satisfied with their procedure at the latest follow-up, with an overall recurrence rate of 5%. A total of 6.5% of athletes required revision surgery, of whom 4% required revision stabilization (all of whom had recurrence). The overall rate of RTP was 88% at mean 6.0 ± 1.7 months postoperatively, with 75% of athletes returning at the same or higher levels than their preinjury level. There were no significant differences for all outcome measures analyzed between patients who had ABR or OL procedures.

Conclusion

GAA athletes with anterior shoulder instability treated with either ABR or OL procedures report excellent clinical outcomes at medium-term follow-up, with high satisfaction rates, excellent functional outcomes, and high rates of RTP. Furthermore, this cohort demonstrates low rates of recurrence after stabilization with few requiring revision surgery.

The Use of Gadolinium in Musculoskeletal MRI-Time to Rethink?

Magnetic resonance imaging has continued to evolve over the recent decades, in part, due to the evolution of gadolinium-based contrast agents and their use. These were initially thought to have a relatively low-risk profile. However, there is mounting evidence that trace amounts of gadolinium are retained within the body. To ascertain the current use of gadolinium in medical practice, we performed a survey of musculoskeletal radiologists, within the United Kingdom, Europe and India. The survey demonstrated varied practices amongst all radiologists with relatively indiscriminate use of gadolinium. In this review, we discuss the current evidence for and against the use of gadolinium in musculoskeletal magnetic resonance imaging.

Correlation of magnetic resonance and arthroscopy in the diagnosis of shoulder injury

BACKGROUND

Advances in shoulder magnetic resonance imaging (MRI) and arthrography (MRA) have revolutionised musculoskeletal diagnosis and surgical planning. Despite this, the overall accuracy of MRI, with or without intra-articular contrast, can be variable.

METHODS

In this prospective non-randomised analysis, 200 participants (74.5% males) with suspected shoulder injuries underwent MRI (41.0%) or MRA followed by arthroscopy. A study specific proforma was developed to ensure consistency of reporting by radiologists and surgeons. The reports were compared to assess the predictive power of MRI/MRA. Specific assessment of rotator cuff tendon appearance, long head of biceps (LHB) tendon appearance, position and anchor, subacromial space, glenoid labrum and humeral cartilage grade were included.

RESULTS

Shoulder MRA demonstrated a higher agreement with arthroscopy than MRI for supraspinatus, infraspinatus and subscapularis tendon appearance (κ = 0.77 vs. κ = 0.61, κ = 0.55 vs. κ = 0.53 and κ = 0.58 vs. κ = 0.46 respectively). There were also superior agreement rates with MRA compared to MRI for LHB tendon appearance (κ = 0.70 vs. κ =0.54) and position (κ = 0.89 vs. κ = 0.72). As an overall assessor of shoulder pathology we found significantly higher total agreement scores when MRA was used (p = 0.002).

DISCUSSION

Whilst magnetic resonance imaging with arthrography is an extremely useful tool to assess underlying pathological shoulder states it does not confer 100% accuracy. In cases whereby this modality is inconclusive, an examination under anaesthesia and diagnostic arthroscopic assessment for the detection of intra-articular shoulder pathology may be considered.

Risk Factors for Failure of Nonoperative Treatment of Posterior Shoulder Labral Tears on Magnetic Resonance Imaging

INTRODUCTION

There are no reports in the literature describing risk factors for failure of nonoperative treatment of patients with posterior labral tears on magnetic resonance imaging (MRI). The purpose of this study is to identify risk factors for failure of nonoperative treatment in patients with an isolated posterior glenoid labral tear identified on MRI only. Patients with posterior labral tears on MRI who fail to improve with nonoperative treatment likely share a constellation of clinical history, physical exam, and radiographic findings.

METHODS

One hundred and fifty-nine active duty military service members under the age of 40 with a posterior labral tear seen on MRI and who were clinically evaluated by a musculoskeletal trained physician were identified. We retrospectively evaluated their records ensuring a minimum of 2 years follow-up after MRI to identify surgical intervention for the posterior labral tear during this time period. Patients were stratified into two groups, those treated with any combination of nonoperative modalities and those treated with posterior labral repair surgery during the 2 years after the MRI. The electronic medical records were reviewed for clinical presentation and physical exam results. We measured multiple radiographic parameters, including glenoid version, size of the tear, and bone loss on MRI. Qualitative and quantitative data were compared between groups using Fisher's exact test and Student's t-test, respectively. This study was conducted under institutional review board approval.

RESULTS

Of the 157 patients' shoulders in our study, 52% (n = 82) of patients with posterior labral tears underwent nonoperative treatment while 48% (n = 75) underwent surgery. The significant risk factors associated with surgery were a history of a specific injury, primary presenting complaint of instability, patient reported history of subluxation, inability to trust their shoulder with overhead activity, decreased strength with weight lifting, positive posterior load/shift exam, positive anterior apprehension, increased osseous glenoid retroversion, increased humeral head subluxation ratio, and anterior labral height (P < 0.05). Patients with a chief complaint of pain were much more likely to succeed with nonoperative treatment while those with instability underwent surgery more often. Ten (12.5%) of the surgical procedures included an anterior and posterior labral repair/stabilization procedure.

CONCLUSION

Patients with an MRI confirmed posterior labral tear, which present with subjective complaints and physical exam maneuvers consistent with instability, appear less likely to be treated nonoperatively. Increased glenoid retroversion and posterior humeral head subluxation may also predispose patients toward surgical treatment. Additionally, posterior labral tears may extend into the anterior labrum more frequently than is recognized on MRI.

Clinical and radiological examination of bony-mediated shoulder instability

The coexistence of glenoid and humeral head bone defects may increase the risk of recurrence of instability after soft tissue repair.

Revealed factors in medical history such as male gender, younger age of dislocation, an increasing number of dislocations, contact sports, and manual work or epilepsy may increase the recurrence rate of instability.

In physical examination, positive bony apprehension test, catching and crepitations in shoulder movement may suggest osseous deficiency.

Anteroposterior and axial views allow for the detection of particular bony lesions in patients with recurrent anterior shoulder instability.

Computed Tomography (CT) with multiplanar reconstruction (MPR) and various types of 3D rendering in 2D (quasi-3D-CT) and 3D (true-3D-CT) space allows not only detection of glenoid and humeral bone defects but most of all their quantification and relations (engaging/not-engaging and on-track/off-track) in the context of bipolar lesion.

Magnetic resonance imaging (MRI) is increasingly developing and can provide an equally accurate measurement tool for bone assessment, avoiding radiation exposure for the patient.

Cite this article: EFORT Open Rev 2020;5:815-827. DOI: 10.1302/2058-5241.5.200049

Thrower's Shoulder: An Approach to MR Imaging Interpretation

In this article, the authors aim to focus on the challenges of interpreting shoulder MR imaging in the throwing athlete with an approach formed by evidence-based literature and clinical experience, with a particular focus on superior labrum tears.

Diagnostic performance of 3D-multi-Echo-data-image-combination (MEDIC) for evaluating SLAP lesions of the shoulder

Background

Superior labral anterior to posterior (SLAP) lesions remain a clinical and diagnostic challenge in routine (non-arthrographic) MR examinations of the shoulder. This study prospectively evaluated the ability of 3D-Multi-Echo-Data-Image-Combination (MEDIC) compared to that of routine high resolution 2D-proton-density weighted fat-saturated (PD fs) sequence using 3 T-MRI to detect SLAP lesions using arthroscopy as gold standard.

Methods

Seventeen consecutive patients (mean age, 51.6 ± 14.8 years, 11 males) with shoulder pain underwent 3 T MRI including 3D-MEDIC and 2D-PD fs followed by arthroscopy. The presence or absence of SLAP lesions was evaluated using both sequences by two independent raters with 4 and 14 years of experience in musculoskeletal MRI, respectively. During arthroscopy, SLAP lesions were classified according to Snyder’s criteria by two certified orthopedic shoulder surgeons. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 3D-MEDIC and 2D-PD fs for detection of SLAP lesions were calculated with reference to arthroscopy as a gold standard. Interreader agreement and sequence correlation were analyzed using Cohen’s kappa coefficient.

Figure 1 demonstrates the excellent visibility of a proven SLAP lesion using the 3D-MEDIC and Fig. 2 demonstrates a false-positive case.

Results

Arthroscopy revealed SLAP lesions in 11/17 patients. Using 3D-MEDIC, SLAP lesions were diagnosed in 14/17 patients by reader 1 and in 13/17 patients by reader 2. Using 2D-PD fs, SLAP lesions were diagnosed in 11/17 patients by reader 1 and 12/17 patients for reader 2. Sensitivity, specificity, PPV, and NPV of 3D-MEDIC were 100.0, 50.0, 78.6, and 100.0% for reader 1; and 100.0, 66.7, 84.6, and 100% for reader 2, respectively. Sensitivity, specificity, PPV, and NPV of 2D-PD fs were 90.9, 83.3, 90.9, and 83.3% for reader 1 and 100.0, 83.3, 91.7, and 100.0% for reader 2. The combination of 2D-PD fs and 3D-MEDIC increased specificity from 50.0 to 83.3% for reader 1 and from 66.7 to 100.0% for reader 2. Interreader agreement was almost perfect with a Cohen’s kappa of 0.82 for 3D-MEDIC and 0.87 for PD fs.

Conclusions

With its high sensitivity and NPV, 3D-MEDIC is a valuable tool for the evaluation of SLAP lesions. As the combination with routine 2D-PD fs further increases specificity, we recommend incorporation of 3D-MEDIC as an additional sequence in conventional shoulder protocols in patients with non-specific shoulder pain.

Imaging modality for measuring the presence and extent of the labral lesions of the shoulder: a systematic review and meta-analysis

BACKGROUND

Multiple published studies quantitatively analysing the diagnostic value of MRI, MR arthrography (MRA) and CT arthrography (CTA) for labral lesions of the shoulder have had inconsistent results. The aim of this meta-analysis was to systematically compare the diagnostic performance of MRI, MRA, CTA and CT.

METHODS

Two databases, PubMed and EMBASE, were used to retrieve studies targeting the accuracy of MRI, MRA, CTA and CT in detecting labral lesions of the shoulder. After carefully screening and excluding studies, the studies that met the inclusion criteria were used for a pooled analysis, including calculation of sensitivity and specificity with 95% confidence intervals (CIs) and the area under the hierarchical summary receiver operating characteristic (HSROC) curves.

RESULTS

The retrieval process identified 2633 studies, out of which two reviewers screened out all but 14 studies, involving a total of 1216 patients who were deemed eligible for inclusion in the meta-analysis. The results assessing the diagnostic performance of MRI vs. MRA for detecting labral lesions showed a pooled sensitivity of 0.77 (95% CI 0.70-0.84) vs. 0.92 (95% CI 0.84-0.96), a specificity of 0.95 (95% CI 0.85-0.98) vs. 0.98 (95% CI 0.91-0.99), and an area under the HSROC curve of 3.78 (95% CI 2.73-4.83) vs. 6.01 (95% CI 4.30-7.73), respectively.

CONCLUSION

MRA was suggested for use in patients with chronic shoulder symptoms or a pathologic abnormality. MRI is by far the first choice recommendation for the detection of acute labral lesions. CT should be a necessary supplemental imaging technique when there is highly suspected glenoid bone damage.

Effect of Anterior Glenoid Labral Tears and Glenoid Bone Loss at the NFL Combine on Future NFL Performance

Background:

Anterior glenohumeral instability is a common abnormality in the young, athletic population, especially in those participating in contact or collision sports.

Purpose:

To examine the effect of anterior labral tears, their associated injuries, and their management on future National Football League (NFL) performance.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective review of all NFL Combine participants from 2009 to 2015 was performed using medical and imaging reports compiled at the NFL Combine. These notes and images were reviewed and analyzed for involved structures, associated injuries, and evidence of previous surgical interventions. The respective NFL draft position, number of NFL games played, number of NFL games started, and NFL snap percentage for each player’s first 2 seasons were collected and compared with a control group and within subgroups.

Results:

Of the 2285 players at the NFL Combine between 2009 and 2015, there were 206 (9%) anterior labral tears confirmed by magnetic resonance imaging, 20 of which were bilateral, for a total of 226 affected shoulders. There were 908 players who fit the criteria for inclusion in the control group. Overall, there were no significant differences between players with anterior labral tears and the control players in terms of draft position (P = .259), games played in their first 2 NFL seasons (P = .391), games started in their first 2 NFL seasons (P = .486), or snap percentage in their first (P = .268) and second (P = .757) NFL seasons. In general, sustaining a concomitant injury with an anterior labral tear (superior labrum from anterior to posterior [SLAP] tear, glenoid bone loss, Hill-Sachs lesion, rotator cuff tear, humeral avulsion of the glenohumeral ligament, and anterior tear combined with posterior tear) negatively affected a player’s NFL draft position when compared with those with an isolated anterior labral tear (P = .003). There was no significant difference between operative and nonoperative management for anterior labral tears in terms of any performance metric.

Conclusion:

A history of anterior labral tears was not significantly associated with future NFL performance. While players with isolated injuries were drafted significantly earlier than those with concomitant injuries, combined injuries did not affect players’ games played, games started, or snap percentage in their first 2 NFL seasons. Glenoid bone loss did significantly decrease draft position; however, the severity of bone loss did not affect draft position, and there were no significant associations between glenoid bone loss and games played, games started, or snap percentage.