Comparison of magnetic resonance arthrography with arthroscopy for imaging of shoulder injuries: retrospective study

Magnetic Resonance Arthrogram Outperforms Standard Magnetic Resonance Imaging 2 Weeks After First Shoulder Dislocation for Labral Tear Diagnosis

PURPOSE

To determine the comparative accuracy and precision of routine magnetic resonance imaging (MRI) versus magnetic resonance (MR) arthrogram in measuring labral tear size as a function of time from a shoulder dislocation.

METHODS

We retrospectively evaluated consecutive patients who underwent primary arthroscopic stabilization between 2012 and 2021 in a single academic center. All patients completed a preoperative MRI or MR arthrogram of the shoulder within 60 days of injury and subsequently underwent arthroscopic repair within 6 months of imaging. Intraoperative labral tear size and location were used as standards for comparison. Three musculoskeletal radiologists independently interpreted tear extent using a clock-face convention. Accuracy and precision of MR labral tear measurements were defined based on location and size of the tear, respectively. Accuracy and precision were compared between MRI and MR arthrogram as a function of time from dislocation.

RESULTS

In total, 32 MRIs and 65 MR arthrograms (total n = 97) were assessed. Multivariate analysis demonstrated that intraoperative tear size, early imaging, and arthrogram status were associated with increased MR accuracy and precision (P < .05). Ordering surgeons preferred arthrogram for delayed imaging (P = .018). For routine MRI, error in accuracy increased by 3.4° per day and error in precision increased by 2.3° per day (P < .001) from time of injury. MR arthrogram, however, was not temporally influenced. Significant loss of accuracy and precision of MRI compared with MR arthrogram occurred at 2 weeks after an acute shoulder dislocation.

CONCLUSIONS

Compared with MR arthrogram, conventional MRI demonstrates time-dependent loss of accuracy and precision in determining shoulder labral tear extent after dislocation, with statistical divergence occurring at 2 weeks.

LEVEL OF EVIDENCE

Level II, retrospective radiographic diagnostic study.

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.

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.

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.

Variability in quantifying the Hill-Sachs lesion: A scoping review

Background

Currently, is there no consensus on a widely accepted measurement technique for calculating the Hill-Sachs lesion (HSL). The purpose of this review is to provide an overview of the techniques and imaging modalities to assess the HSL pre-operatively.

Methods

Four online databases (PubMed, Embase, MEDLINE, and COCHRANE) were searched for literature on the various modalities and measurement techniques used for quantifying HSLs, from data inception to 20 November 2021. The Methodological Index for Non-Randomized Studies tool was used to assess study quality.

Results

Forty-five studies encompassing 3413 patients were included in this review. MRA and MRI showed the highest sensitivity, specificity, and accuracy values. Intrarater and interrater agreement was shown to be the highest amongst MRA. The most common reference tests for measuring the HSL were arthroscopy, radiography, arthro-CT, and surgical techniques.

Conclusion

MRA and MRI are reliable imaging modalities with good test diagnostic properties for assessment of HSLs. There is a wide variety of measurement techniques and imaging modalities for HSL assessment, however a lack of comparative studies exists. Thus, it is not possible to comment on the superiority of one technique over another. Future studies comparing imaging modalities and measurement techniques are needed that incorporate a cost-benefit analysis.

Shoulder instability in military personnel: diagnosis and outcomes of arthroscopic stabilisation

INTRODUCTION

Shoulder instability is a common problem for military personnel due to the highly physical demands of work and training. This study assessed the pattern of glenoid labrum tears suffered by serving UK military personnel, the reliability of preoperative diagnostic methods (magnetic resonance arthrogram (MRA) vs clinical examination) and, finally, the outcomes of arthroscopic stabilisation in terms of satisfaction, pain, and return to sport and full deployment.

METHODS

Retrospective demographic and clinical data were collected for all patients within our unit who underwent arthroscopic shoulder stabilisation between September 2016 and January 2019. Patients underwent clinical examination for instability and subsequent imaging with MRA. For service evaluation, patient-reported outcome measure data and occupational outcome data were gathered preoperatively and postoperatively.

RESULTS

41 military patients with shoulder instability were treated with arthroscopic stabilisation. 24.4% had an isolated anterior tear, and 41.5% had complex two-zone or pan-labral tears identified on arthroscopy. Clinical examination showed higher sensitivity, accuracy and negative predictive value for all labral tear patterns compared with MRA. Mean preoperative Oxford Shoulder Instability Score score was 18.58 (SE ±1.67) and mean postoperative score was 41.5 (SE ±1.13). 82.14% of the patients returned to full deployment during the study period and 85% had returned to sports.

CONCLUSION

Complex labral tear patterns are common in military personnel with shoulder instability, and clinical examination appears to be more effective than imaging at predicting injury pattern. Patients respond well to arthroscopic stabilisation with good rates of return to work and sport, regardless of chronicity of injury.

Two paleopathological cases suggestive of paralabral cysts of the shoulder

OBJECTIVE

To undertake differential diagnosis of scapular bone defects found in two medieval skeletons buried in different necropoles of Friuli Venezia Giulia (Italy) and to evaluate the clinical significance of paralabral cysts in the context of shoulder pathology.

MATERIALS

Individual JoT36 is an adult male exhumed from a necropolis belonging to a rural agricultural settlement dated to the 10th to 11th century A.D. Individual CIVT58 is an adult male from a Langobard necropolis dated to 630-670 A.D.

METHODS

Macroscopic examination of the skeletons was performed using standard osteological methods and review of pertinent clinical literature to assist differential diagnosis.

RESULTS

Between the glenoid cavity and the spinoglenoid notch of the right scapula of JoT36 there is a multilocular circular defect adjacent to the glenoid rim. On the neck of the left scapula of CIVT58, immediately above the spinoglenoid notch, there is a unilocular circular depression. In both cases, the cortical bone appears smooth without any evidence of erosion or sclerosis.

CONCLUSIONS

Skeletal findings and historical/archaeological contexts of both cases are compatible with the diagnosis of paralabral cysts.

SIGNIFICANCE

Paralabral cysts are relatively frequently observed in clinical settings but very few examples have been documented in paleopathological literature. This study seeks to improve recognition and interpretation of this pathology in historical/archaeological contexts.

LIMITATIONS

Findings from a case report can neither generate epidemiological information nor be generalized.

SUGGESTIONS FOR FURTHER RESEARCH

Identification of new cases may add valuable information about lifestyles and related shoulder pathologies in ancient times.

Concomitant Glenohumeral Instability and Rotator Cuff Injury: An Epidemiologic and Case-Control Analysis in Military Cadets

INTRODUCTION

Concomitant rotator cuff tear and glenohumeral instability in a large cohort of young and active patients has not been examined. The purpose of this study was to investigate the incidence, associated variables, and outcomes in military cadets undergoing shoulder stabilization procedures with these concomitant pathologies.

METHODS

A retrospective cohort study of a consecutive series of collegiate patients who underwent shoulder stabilization from 2014 to 2018 at a single service academy was conducted. Exclusion criteria were noncadets, revision instability cases, multidirectional instability, and prior rotator cuff repair. A nested case-control analysis was done in a matched series of patients with and without MRI evidence of rotator cuff tear. Baseline demographics, VAS pain scale, physical therapy duration, and time to surgery were analyzed. Postoperative metrics included rate of recurrent instability, subjective outcomes, VAS pain scale, and military-specific criteria.

RESULTS

Three hundred twenty-four cadets met the inclusion criteria, including 272 men and 52 women averaging 20.53 ± 1.80 years of age. MRI demonstrated concomitant rotator cuff tears in 5.56% of cases. A matched case-control comparison between patients with (rotator cuff tear group) and without (no rotator cuff tear group) rotator cuff tear showed no differences in preoperative data, recurrent instability rate, or postoperative VAS pain scores (0.24 versus 0.88, P = 0.207) at mean 44-month follow-up. Fifteen of 17 patients (88.2%) in each group returned to full activity (P > 0.999). No patients failed to graduate due to shoulder concerns. No patients in the rotator cuff tear group underwent a medical board for separation from the military compared with 2 (11.8%) in the no rotator cuff tear group (P = 0.163).

CONCLUSIONS

The incidence of concomitant rotator cuff tears in this study of military cadets undergoing shoulder stabilization was 5.56%. In a matched cohort comparison, the presence of a rotator cuff tear on preoperative MRI was not associated with inferior clinical outcomes.

Posterior Labral Tear Extension Concomitant With Shoulder Bankart Injuries Is not Uncommon

Purpose

To identify the rate and risk factors of posterior labral involvement in operatively managed Bankart lesions and assess the effectiveness of MRI arthrogram for preoperative identification of such injury patterns.

Methods

A consecutive cohort of patients undergoing arthroscopic Bankart repair were retrospectively reviewed. All subjects underwent a prearthroscopy MRI arthrogram. Operative findings were used as the gold standard for posterior labral tear extension. Patient demographic and surgical data were then analyzed to identify independent factors associated with the presence of concomitant posterior labral injury.

Results

Of 124 patients undergoing arthroscopic Bankart stabilization, 23 (19%) were noted to demonstrate posterior labral injury on arthroscopic evaluation. Factors associated with injury to the posterior labrum included those sustaining two or fewer dislocations events (P =.001), an earlier average presentation (P = .001), and a reported “contact” mechanism of dislocation (P = .02). Posterior labral involvement did not correlate with surgical positioning (beach-chair versus lateral) or the need for revision surgery. On the basis of review of preoperative imaging, MRI arthrogram demonstrated a sensitivity of 83% and a specificity of 95% for detection of posterior labral injury.

Conclusions

Posterior propagation of Bankart lesions is relatively common following shoulder dislocations, with a rate of 18.5%. Risk factors for posterior labral extension include two or fewer dislocations, early presentation from the time of injury, and contact sports. On the basis of these findings, careful assessment of the posterior labrum on MRI arthrogram may reveal the majority, but not all, of these lesions.

Level of Evidence

Level III, retrospective case-controlled study.

Glenoid Labral Injuries Are More Common Posteriorly Than Superiorly and Are Combined Across Multiple Areas of the Glenoid

Purpose

To categorize arthroscopically observed labral injuries to include location on the glenoid and frequency of the injuries in each location.

Methods

Patients undergoing arthroscopic labral surgery between January 2018 and June 2020 were reviewed. Inclusion criteria for labral injury were consistently applied and included history, clinical examination and imaging findings, and failure of rehabilitation. Exclusion criteria included arthritis, adhesive capsulitis, and previous surgery. Injury locations were categorized into superior, anterior, and/or posterior areas on the glenoid and as isolated in one area or combined in more than one area. Injury patterns also were evaluated. Interrater and intrarater agreement was assessed between 2 raters for injury location and tear pattern for 22 randomly assigned cases.

Results

In total, 167 cases met the inclusion criteria. Injuries were found in all areas. Combined injuries were found almost twice as often as isolated injuries (63.5% vs 37.5%). Isolated posterior injuries had the greatest frequency of all specific injury types (26.3%). Isolated superior injuries (SLAP 2-4) had a frequency of 7.2%. Tear patterns included peel back, separation/split, insubstance injury, peripheral rim flattening, and extension into the posterior inferior glenohumeral ligament. Interrater was excellent for all tear locations (intraclass correlation coefficient ≥0.85) whereas intrarater agreement was good to excellent (intraclass correlation coefficient ≥0.63).

Conclusions

Labral injuries that are associated with clinical symptoms can occur as isolated or combined types in the superior, anterior, and posterior glenoid areas and can display multiple injury patterns. Combined types of injuries are almost twice as common as those that are isolated in one area. Posterior injuries, isolated or combined, are frequent but superior injuries are less common

Level of Evidence

Level IV, therapeutic case series.

Comparing shoulder maneuvers to magnetic resonance imaging and arthroscopic findings in patients with supraspinatus tears

BACKGROUND

Shoulder maneuvers and magnetic resonance imaging (MRI) are performed to diagnose supraspinatus tendon tears regardless of arthroscopy exam. Although there are many studies on this subject, there is a lack of studies comparing the sensitivity (Se) and specificity (Sp) of shoulder maneuvers and MRI to arthroscopic findings (intact, partial, or full thickness supraspinatus tendon tear).

AIM

To compare the diagnostic values of shoulder maneuvers with MRI for supraspinatus tendon tears in patients undergoing shoulder arthroscopy.

METHODS

A total of 199 consecutive patients from four orthopedic centers met the eligibility criteria of shoulder pain persisting for at least four weeks. They were prospectively enrolled in this study from April 2017 to April 2019. Seven clinical tests (full can, empty can, drop arm, Hawkins’, painful arc, Neer’s sign and resisted external rotation) and MRI were performed, and all were compared with surgical findings. Full can, empty can and resisted external rotation tests were interpreted as positive in the case of pain and/or weakness. We assessed the Se, Sp, accuracy, positive predictive value (PPV) and negative predictive value (NPV), positive and negative likelihood ratio and diagnostic odds ratio for overall, partial and full-thickness supraspinatus tears.

RESULTS

MRI had the highest Se for overall (0.97), partial (0.91) and full-thickness (0.99) tears; moreover, MRI had the highest NPV: 0.90, 0.88 and 0.98 for overall, partial and full-thickness tears, respectively. For overall supraspinatus tears, the Se and PPV were: Painful arc (Se = 0.85/PPV = 0.91), empty can (pain) (Se = 0.80/PPV = 0.89), full can (pain) (Se = 0.78/PPV = 0.90), resisted external rotation (pain) (Se = 0.48/PPV = 0.87), drop arm (Se = 0.19/PPV = 0.97), Neer’s sign (Se = 0.78/PPV = 0.93) and Hawkins’ (Se = 0.80/PPV = 0.88). MRI had the highest PPV (0.99). The Hawkin’s test had the highest false positive rate in patients with intact tendons (0.36). The Sp of the empty can and full can (both tests positive for pain and weakness), drop arm and MRI were: 0.93, 0.91, 0.98 and 0.96, respectively. For partial and full-thickness tears, the empty can test (positive for pain and weakness) had a Sp of 0.93, and the drop arm and MRI had the same Sp (0.98).

CONCLUSION

Physical examination demonstrated good diagnostic value, the drop arm test had a Sp as good as MRI for supraspinatus tears; however, MRI was more accurate in ruling out tears. The Hawkins’ test had high false-positive findings in patients with intact tendons.

Variability of glenoid labral tear patterns: a study of 280 sequential surgical cases

BACKGROUND

Glenoid labrum tears are a common cause of shoulder pain and instability and tear patterns have historically been ascribed into categorical descriptions such as anterior, posterior, and superior labral tears (SLAP [superior labrum anterior and posterior]) with multiple subtypes. Although often quoted as representing no more than 10% of instabilities, posterior shoulder instability may be more common than previously recognized. The purpose of this study was to review observed labral tear patterns and compare incidence and morphologies to historical descriptions.

METHODS

All patients undergoing arthroscopic or open labral repair (Current Procedural Terminology codes 29806, 29807, 23455, 23460, 23462, 23465) by 2 fellowship-trained shoulder surgeons from July 2012 to May 2019 were retrospectively reviewed. Labral tears were categorized into 3 groups: exclusively anterior to the midline of the glenoid, exclusively posterior, and those crossing the midline of the glenoid. Chief complaint, mechanism of injury, hand dominance, preoperative MRI interpretation by surgeon, and independent radiologist were analyzed for each tear type.

RESULTS

During the 7-year period, 280 patients underwent arthroscopic or open labral repair. Sixty percent of tears were traumatic, with dislocation being the most common traumatic mechanism at 31.4%. Ten distinct tear patterns were identified: 3 types of 90° tears (anteroinferior, posteroinferior, and posterosuperior), 4 types of 180° tears (anterior, posterior, inferior, and SLAP), 2 types of 270° tears (anteroinferior and anterosuperior), and 360° labral tears. A total of 134 tears (47.9%) were classified as posterior, and 72 tears (25.7%) were anterior. Seventy-four tears (26.4%) were combined anterior-posterior tears. Labral tears involving some portion of the posterior labrum constituted 74% of tears. A significant association between tear location and primary complaint (P < .001) was noted. Patients with anterior tears complained of only instability in 62.5% of cases, and only pain in 22%. Patients with posterior labral tears complained primarily of pain in 68% of cases, and instability in 21%. There was an accurate preoperative diagnosis given by both radiologists and surgeons on 30% (n = 63) of the tears.

CONCLUSION

There is a wide variety of labral tear patterns identified at the time of surgery, and the incidence of posterior labral tears is higher than previously described. Isolated Bankart lesions are relatively rare and are often associated with more extensive labral lesions. Patients with posterior labral pathology more often complain of pain rather than instability, whereas patients with anterior labral tears more often complain of instability.

Improving detection of Hill-Sachs fractures on radiographs

OBJECTIVE

To investigate factors which affect radiographic diagnosis of Hill-Sachs fractures, and find criteria which improve detection.

MATERIALS AND METHODS

Retrospective search was made for the term "Hill Sachs" within MRI reports in our local PACS system, and cases with post-reduction radiographs were included in the study. Prospective diagnoses and subspecialty MSK training of the interpreting radiologist of record were recorded. Images were then retrospectively reviewed by two observers and statistical analysis was performed.

RESULTS

Our retrospective study included 181 cases, of which 35% had prospective radiographic diagnosis of Hill-Sachs fracture. Retrospective review found that 73% of the radiograph series had at least 1 sign of a Hill-Sachs fracture. The internal rotation view showed a Hill-Sachs lesion in 59% of cases, but did not detect it in 14% of cases, where the lesion was instead visible on axillary, external rotation, and/or scapular Y view. Odds ratio of prospective Hill-Sachs detection on radiographs was 2.68 for musculoskeletal fellowship-trained radiologists versus non-musculoskeletal-trained radiologists.

CONCLUSION

Hill-Sachs fractures are often not recognized on post-reduction radiographs. Diagnosis of Hill-Sachs lesion can be significantly increased if radiologists are aware that the internal rotation view may fail to show the injury, and if all 4 views of a shoulder series are scrutinized.

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.

Interobserver agreement for detecting Hill-Sachs lesions on magnetic resonance imaging

BACKGROUND

Our aim is to determine the interobserver reliability for surgeons to detect Hill-Sachs lesions on magnetic resonance imaging (MRI), the certainty of judgement, and the effects of surgeon characteristics on agreement.

METHODS

Twenty-nine patients with Hill-Sachs lesions or other lesions with a similar appearance on MRIs were presented to 20 surgeons without any patient characteristics. The surgeons answered questions on the presence of Hill-Sachs lesions and the certainty of diagnosis. Interobserver agreement was assessed using the Fleiss' kappa (κ) and percentage of agreement. Agreement between surgeons was compared using a technique similar to the pairwise t-test for means, based on large-sample linear approximation of Fleiss' kappa, with Bonferroni correction.

RESULTS

The agreement between surgeons in detecting Hill-Sachs lesions on MRI was fair (69% agreement; κ, 0.304; p<0.001). In 84% of the cases, surgeons were certain or highly certain about the presence of a Hill-Sachs lesion.

CONCLUSIONS

Although surgeons reported high levels of certainty for their ability to detect Hill-Sachs lesions, there was only a fair amount of agreement between surgeons in detecting Hill-Sachs lesions on MRI. This indicates that clear criteria for defining Hill-Sachs lesions are lacking, which hampers accurate diagnosis and can compromise treatment.

Accuracy and Reliability of Imaging Modalities for the Diagnosis and Quantification of Hill-Sachs Lesions: A Systematic Review

PURPOSE

To determine the reliability and accuracy of different imaging modalities in assessing Hill-Sachs lesions within the setting of anterior shoulder instability.

METHODS

A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines using the PubMed, Scopus, Embase, and Cochrane Library databases. The inclusion criteria were clinical trials or cadaveric studies that assessed the accuracy of humeral head bone loss imaging or reliability and English-language articles. The exclusion criteria were animal studies; imaging studies without measures of accuracy, reliability, or clinical predictive power; studies of shoulder injuries without humeral head bone loss; editorials; abstracts; reviews; case reports; and surveys. The search terms included "imaging" OR "radiographic" OR "CT" OR "MRI" AND "Hill-Sachs" OR "humeral head bone loss." Assessment of the methodologic quality of the included studies was performed using the original Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool.

RESULTS

Forty studies (2,560 shoulders) met the inclusion criteria and were assessed. For diagnosing the presence of Hill-Sachs lesions, computed tomography (CT) arthrography had the highest reported accuracy (median, 91%; range, 66%-100%). For the same assessment, CT arthrography also had the greatest reported sensitivity (median, 94%; range, 50%-100%). For the quantification of Hill-Sachs lesion parameters, reported intraobserver reliabilities were highest for 3-dimensional (3D) CT (intraclass correlation coefficient [ICC] range, 0.916-0.999), followed by 2-dimensional CT (ICC range, 0.858-0.861) and magnetic resonance imaging (MRI) (ICC range, 0.28-0.97). For the same quantification parameters, interobserver reliabilities were also reported for 3D CT (ICC range, 0.772-0.996), 2-dimensional CT (ICC range, 0.721-0.879), and MRI (κ range, 0.444-0.700). Intraobserver reliabilities for determining glenoid tracking were only reported for 3D CT (κ range, 0.730-1.00; ICC range, 0.803-0.901) and MRI (ICC range, 0.770-0.790).

CONCLUSIONS

This study shows that the current literature supports a variety of different imaging modalities that provide clinically acceptable accuracy in diagnosing and quantifying Hill-Sachs lesions, as well as determining whether they will cause persistent anterior shoulder instability. Furthermore, this systematic review justifies that further research is needed to help develop a treatment algorithm on the proper imaging modalities needed to help treat patients with anterior shoulder instability that is both reliable and financially acceptable.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I through IV studies.

Comparison of MRI and MRA for the diagnosis of rotator cuff tears: A meta-analysis

BACKGROUND

Numerous quantitatively based studies measuring the accuracy of MRI and MRA for the diagnosis of rotator cuff tears remain inconclusive. In order to compare the accuracy of MRI with MRA in detection of rotator cuff tears a meta-analysis was performed systematically.

METHODS

PubMed/Medline and Embase were utilized to retrieve articles comparing the diagnostic performance of MRI and MRA for use in detecting rotator cuff tears. After screening and diluting out the articles that met inclusion criteria to be used for statistical analysis the pooled evaluation indexes including sensitivity and specificity as well as hierarchical summary receiver operating characteristic (HSROC) curves with 95% confidence interval (CI) were calculated.

RESULTS

Screening determined that 12 studies involving a total of 1030 patients and 1032 shoulders were deemed viable for inclusion in the meta-analysis. The results of the analysis showed that MRA has a higher sensitivity and specificity than MRI for the detection of any tear; similar results were observed in the detection of full-thickness tears. However, for the detection of partial-thickness tear, MRI has similar performance with MRA.

CONCLUSION

MRI is recommended to be a first-choice imaging modality for the detection of rotator cuff tears. Although MRA have a higher sensitivity and specificity, it cannot replace MRI after the comprehensive consideration of accuracy and practicality.

Detecting Rotator Cuff Tears: A Network Meta-analysis of 144 Diagnostic Studies

BACKGROUND

Many imaging techniques have been developed for the detection of rotator cuff tears (RCTs). Despite numerous quantitative diagnostic studies, their relative accuracy remains inconclusive.

PURPOSE

To determine which of 3 commonly used imaging modalities is optimal for the diagnosis of RCTs.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

Studies evaluating the performance of magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA), and ultrasound (US) used in the detection of RCTs were retrieved from the PubMed/MEDLINE and Embase databases. Diagnostic data were extracted from articles that met the inclusion/exclusion criteria. A network meta-analysis was performed using an arm-based model to pool the absolute sensitivity and specificity, relative sensitivity and specificity, and diagnostic odds ratio as well as the superiority index for ranking the probability of these techniques.

RESULTS

A total of 144 studies involving 14,059 patients (14,212 shoulders) were included in this network meta-analysis. For the detection of full-thickness (FT) tears, partial-thickness (PT) tears, or any tear, MRA had the highest sensitivity, specificity, and superiority index. For the detection of any tear, MRI had better performance than US (sensitivity: 0.84 vs 0.81, specificity: 0.86 vs 0.82, and superiority index: 0.98 vs 0.22, respectively). With regard to FT tears, MRI had a higher sensitivity and superiority index than US (0.91 vs 0.87 and 0.67 vs 0.28, respectively) and a similar specificity (0.88 vs 0.88, respectively). The results for PT tears were similar to the detection of FT tears. A sensitivity analysis was performed by removing studies involving only 1 arm for FT tears, PT tears, or any tear, and the results remained stable.

CONCLUSION

This network meta-analysis of diagnostic tests revealed that high-field MRA had the highest diagnostic value for detecting any tear, followed by low-field MRA, high-field MRI, high-frequency US, low-field MRI, and low-frequency US. These findings can help guide clinicians in deciding on the appropriate imaging modality.

[Current concepts of diagnostic techniques and measurement methods for bone defect in patient with anterior shoulder instability]

Objective

To summarize the diagnosis and measurement methods of bone defect in anterior shoulder instability (glenoid bone defect and Hill-Sachs lesion).

Methods

The related literature on the diagnosis and measurement of the bone defect in anterior shoulder instability was reviewed and summarized.

Results

The commonly used techniques for the diagnosis of anterior glenoid bone defect and Hill-Sachs lesion of humeral head include X-ray, CT, MRI, arthroscopy, arthrography. The methods for measuring the degree of anterior glenoid bone defect include Griffith method, glenoid index method, Pico method, and best-fit circle method. The indexes for measuring the Hill-Sachs lesion include the length, width, depth, and volume. X-ray is mainly used for primary screening. Best-fit circle method on three-dimensional (3D) CT reconstruction is commonly used to measure the glenoid bone defect currently. Glenoid track theory on 3D CT reconstruction is popular in recent years. Reliability of measuring the glenoid bone defect and Hill-Sachs lesion with MRI and arthroscopy is still debatable. Arthrography is more and more used in the diagnosis of shoulder joint instability of bone defect and concomitant soft tissue injury.

Conclusion

How to improve the accuracy of evaluating glenoid bone defect and Hill-Sachs lesion before surgery still need further study.