Assessment of the long head of the biceps tendon of the shoulder with 3T magnetic resonance arthrography and CT arthrography

Biceps Pulley Lesions: Diagnostic Accuracy of Nonarthrographic Shoulder MRI and the Value of Various Diagnostic Signs

BACKGROUND

There is limited data in the literature regarding the role of nonarthrographic MRI for detecting biceps pulley (BP) lesions.

PURPOSE

To assess the accuracy of nonarthrographic MRI for detecting BP lesions, and to evaluate the diagnostic value of various MRI signs (superior glenohumeral ligament discontinuity/nonvisibility, long head of biceps (LHB) displacement sign or subluxation/dislocation, LHB tendinopathy, and supraspinatus and subscapularis tendon lesions) in detecting such lesions.

STUDY TYPE

Retrospective.

POPULATION

84 patients (32 in BP-lesion group and 52 in BP-intact group-as confirmed by arthroscopy).

FIELD STRENGTH/SEQUENCE

1.5-T, T1-weighted turbo spin echo (TSE), T2-weighted TSE, and proton density-weighted TSE spectral attenuated inversion recovery (SPAIR) sequences.

ASSESSMENT

Three radiologists independently reviewed all MRI data for the presence of BP lesions and various MRI signs. The MRI signs and final MRI diagnoses were tested for accuracy regarding detecting BP lesions using arthroscopy results as the reference standard. Furthermore, the inter-reader agreement (IRA) between radiologists was determined.

STATISTICAL TESTS

Student's t-tests, Chi-squared, and Fisher's exact tests, and 4-fold table test were used. The IRA was calculated using Kappa statistics. A P-value <0.05 was considered statistically significant.

RESULTS

The sensitivity, specificity, and accuracy of nonarthrographic MRI for detecting BP lesions were 65.6%-78.1%, 90.4%-92.3%, and 81%-86.9%, respectively. The highest accuracy was noticed for the LHB displacement sign (84.5%-86.9%), and the highest sensitivity was registered for the LHB tendinopathy sign (87.5%). Furthermore, the highest specificity was observed for the LHB displacement sign and LHB subluxation/dislocation sign (98.1%-100%). The IRA regarding final MRI diagnosis and MRI signs of BP lesions was good to very good (κ = 0.76-0.98).

DATA CONCLUSION

Nonarthrographic shoulder MRI may show good diagnostic accuracy for detecting BP lesions. The LHB displacement sign could serve as the most accurate and specific sign for diagnosis of BP lesions.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

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.

Detection and Quantitative Assessment of Arthroscopically Proven Long Biceps Tendon Pathologies Using T2 Mapping

This study evaluates how far T2 mapping can identify arthroscopically confirmed pathologies in the long biceps tendon (LBT) and quantify the T2 values in healthy and pathological tendon substance. This study comprised eighteen patients experiencing serious shoulder discomfort, all of whom underwent magnetic resonance imaging, including T2 mapping sequences, followed by shoulder joint arthroscopy. Regions of interest were meticulously positioned on their respective T2 maps, capturing the sulcal portion of the LBT and allowing for the quantification of the average T2 values. Subsequent analyses included the calculation of diagnostic cut-off values, sensitivities, and specificities for the detection of tendon pathologies, and the calculation of inter-reader correlation coefficients (ICCs) involving two independent radiologists. The average T2 value for healthy subjects was measured at 23.3 ± 4.6 ms, while patients with tendinopathy displayed a markedly higher value, at 47.9 ± 7.8 ms. Of note, the maximum T2 value identified in healthy tendons (29.6 ms) proved to be lower than the minimal value measured in pathological tendons (33.8 ms), resulting in a sensitivity and specificity of 100% (95% confidence interval 63.1-100) across all cut-off values ranging from 29.6 to 33.8 ms. The ICCs were found to range from 0.93 to 0.99. In conclusion, T2 mapping is able to assess and quantify healthy LBTs and can distinguish them from tendon pathology. T2 mapping may provide information on the (ultra-)structural integrity of tendinous tissue, facilitating early diagnosis, prompt therapeutic intervention, and quantitative monitoring after conservative or surgical treatments of LBT.

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.

The long head of biceps at the shoulder: a scoping review

BACKGROUND

This review aimed to explore the available literature to update our understanding of the long head of biceps (LHB) at the shoulder. Synthesise our findings to identify emergent themes and knowledge gaps to inform future research and management directions.

METHODS

PubMed, Embase, Cinahl, SportDiscus, CENTRAL, and Web of Science were searched from inception to 31st December 2021. Articles were included if they referenced adult participants > 18 years of age and were written in English.

RESULTS

214 articles were included in the final analysis, and results were categorised into six emergent themes: (1) Anatomy - Normal anatomical variation of the biceps from aberrant origins, third and fourth accessory heads, and an absence of the LHB tendon (LHBT) are not necessarily benign, with shoulder pain and instability a commonly reported theme. (2) Function - Bicep's role in glenohumeral elevation and stability in healthy shoulders is minimal. In contrast, LHB has a more significant role in shoulder stability and humeral head depression in subjects with rotator cuff failure or an absent LHBT. (3) Pathology - There is an association between LHB tendinopathy, rotator cuff disease, LHBT instability and occult rotator cuff tears. Early recruitment and hyperactivity of the LHB in subjects with symptomatic rotator cuff tears and instability suggest a potential compensatory role. (4) Assessment - The limited diagnostic utility of special orthopaedic tests in assessing LHBT pathology was a consistent theme. The utility of magnetic resonance imaging and ultrasound to identify full-thickness tendon tears and instability of the LHBT was moderate to high. However, the utility of clinical tests and imaging may be underestimated due to arthroscopy's limitations in fully visualising the proximal LHBT. (5) Non-Surgical Management - Ultrasound-guided injections into the biceps sheath show greater accuracy and patient outcomes than blinded injections; however, the entry of injectate into the intraarticular glenohumeral joint may have unwanted complications. (6) Surgical management - For the surgical management of biceps pathology with or without rotator cuff pathology, both biceps tenodesis and tenotomy report similar improvements in pain without any significant adverse effect on strength or function. Tenodesis favoured higher overall constant scores and a lower incidence of Popeye deformity and cramping arm pain, with tenotomy trending to be more cost and time effective. For patients with a healthy LHBT, rotator cuff repair with adjunctive tenodesis or tenotomy fails to provide additional clinical improvements compared to rotator cuff repair in isolation.

CONCLUSIONS

The scoping review highlights the variability of biceps anatomy, which is not necessarily benign and suggests a minimal role of the LHB in shoulder elevation and stability in healthy individuals. In contrast, individuals with rotator cuff tears experience proximal humeral migration and demonstrate hyperactivity of the LHB, suggesting a potential compensation role. The observed prevalence of LHBT pathology with rotator cuff tears is well established; however, the cause-and-effect relationship between LHBT pathology and rotator cuff disease is undetermined. The diagnostic utility of clinical tests and imaging to exclude LHBT pathology may be understated due to the limitations of arthroscopy to visualise the proximal LHBT fully. Rehabilitation programs for the LHB are understudied. Similar post-surgical clinical outcomes are observed for tenodesis and tenotomy for biceps and rotator cuff-related shoulder pain. Subjects undergoing biceps tenodesis are less likely to have cramping arm pain and a Popeye deformity than patients undergoing biceps tenotomy. The significance of routine surgical removal of the LHBT and sequelae on rotator cuff tear progression to failure and long-term shoulder function is unknown, and further research is required.

PRE-REGISTRATION

OSF: https://osf.io/erh9m.

3D imaging has good specificity but poor sensitivity for the diagnosis of pathologies of the long head of the biceps: a systematic review and meta-analysis

PURPOSE

To systematically review and meta-analyse the literature to determine which three-dimensional (3D) imaging modality provides the best diagnostic accuracy to detect pathologies of the long head of the biceps tendon (LHBT).

MATERIALS AND METHODS

A search was performed on PubMed, Embase^®, and Cochrane. Studies that compared the diagnostic accuracy of 3D imaging modalities versus arthroscopy for the assessment of LHBT pathologies were included. Studies assessing superior labral anterior posterior (SLAP) lesions were excluded.

RESULTS

Fifteen studies were included; nine were eligible for meta-analysis. Six studies on instability indicated a sensitivity of 0.68 (CI 0.46-0.84) and specificity of 0.76 (CI 0.68-0.82). Four studies on full-thickness tears indicated a sensitivity of 0.56 (CI 0.28-0.81) and specificity of 0.97 (CI 0.93-0.99). Four studies on partial-thickness tears indicated a sensitivity of 0.52 (CI 0.20-0.82) and specificity of 0.64 (CI 0.25-0.91). Two studies on any tear indicated a sensitivity of 0.58 (CI 0.28-0.83) and specificity of 0.99 (CI 0.93-1.00). Only one study on other pathologies indicated a sensitivity of 0.61 and specificity of 0.84.

CONCLUSION

To diagnose LHBT pathologies, 3D imaging modalities overall have low-to-moderate sensitivity, but high-to-excellent specificity. The consistency in reported sensitivity is generally poor, while the consistency and reported specificity is good for the detection of instability, full-thickness tears and any tear, but poor for the detection of partial-thickness tears. 3D imaging may be adequate to rule out LHBT pathologies, but are not sufficiently reliable to confirm the presence of such pathologies.

LEVEL OF EVIDENCE

III.

Diagnostic accuracy of magnetic resonance imaging for partial tears of the long head of the biceps tendon in patients with rotator cuff tears

Background

Magnetic resonance imaging (MRI) is useful for diagnosing shoulder diseases preoperatively. However, detection of partial tears of the long head of the biceps tendon (LHBT) using current clinical tests and imaging modalities is difficult. We aimed to evaluate the accuracy of radial-slice MRI for diagnosing partial tears of the LHBT. We hypothesized that radial-slice MRI may be a valuable diagnostic tool for assessing diagnosing tears of the LHBT.

Methods

We retrospectively investigated 118 patients who underwent shoulder arthroscopy for rotator cuff tears. Intraoperative LHBT findings were compared with the identification of partial tears of the LHBT on conventional-slice MRI and radial-slice MRI, using a 3.0-T system. We calculated sensitivity, specificity, accuracy, and positive and negative predictive values for the detection of LHBT tears. Inter- and intraobserver reliability for radial-slice MRI was calculated using kappa statistics.

Results

We diagnosed 69 patients (58%) without any LHBT tears and 49 with partial tears (42%), arthroscopically. Sensitivity, specificity, accuracy, and positive and negative predictive values of conventional-slice MRI for detection of partial tears of the LHBT were 52%, 94%, 78%, 92%, and 58%, respectively. Radial-slice MRI had 84% sensitivity, 90% specificity, 86% accuracy, and 92% positive and 80% negative predictive values for partial tears of the LHBT. Inter- and intraobserver reliability for radial-slice MRI was 0.69 and 0.74, respectively, corresponding to high reproducibility and defined as good.

Conclusion

Radial-slice MRI demonstrated significantly higher sensitivity than conventional-slice MRI. These results indicate that radial-slice MRI is useful for diagnosing LHBT partial tears.

Computed tomography arthrography of the shoulder with tin filter-based spectral shaping at 100 kV and 140 kV

BACKGROUND

Tin filter-based spectral shaping has been used for low-dose and ultra-low-dose computed tomography (CT) in several body parts. However, studies of shoulder CT arthrography with spectral shaping are limited.

PURPOSE

To investigate image quality and radiation dose of shoulder CT arthrography with tin filter-based spectral shaping at 100 kV (Sn 100 kV) and 140 kV (Sn 140 kV) in comparison with the conventional protocol.

MATERIAL AND METHODS

Ninety-nine shoulder CT arthrographies with protocols of Sn 100 kV (n = 32), Sn 140 kV (n = 25), and conventional 120 kV (n = 42) were retrospectively evaluated. Qualitative image quality, CT attenuations of intra-articular contrast mixture and tissues, background noise, contrast-to-noise ratios (CNRs), and figures of merit were assessed. Radiation doses were compared.

RESULTS

CT arthrographies with Sn 100 kV and Sn 140 kV yielded approximately 70% and 60% radiation dose reduction, respectively, compared with the conventional 120 kV (P < 0.001). Qualitative image noise and quantitative background noise of Sn 100 kV and Sn 140 kV were significantly less than those of the conventional protocol. Qualitative image contrast, CT attenuations of intra-articular contrast mixture and tissues, and CNRs for Sn 100 were similar to those of the conventional 120 kV. However, Sn 140 kV showed significantly lower qualitative contrast and CNRs than 120 kV. Sn 100 kV was the most dose efficient among the three protocols.

CONCLUSION

Shoulder CT arthrography with Sn 100 kV substantially reduced radiation dose and image noise and maintained image contrast, compared with the conventional protocol.

Long head biceps tendon instability: diagnostic performance of known and new MRI diagnostic signs

OBJECTIVE

The aim of this work was to evaluate the inter-observer agreement and diagnostic performance values of 7 MRI signs (3 known and 4 new) of long head biceps tendon instability.

MATERIALS AND METHODS

MRI of 86 patients were retrospectively evaluated. Inter-observer agreement and diagnostic performance of each diagnostic sign and of all combined signs (with the exception of detour sign) were tested for identification of biceps tendon instability, with arthroscopy as the reference standard.

RESULTS

Agreement between expert operators was moderate to good. Sensitivity, specificity, and sign accuracy showed a variation respectively of the following: humeral chondral print 72-80%, 62-68%, and 70-76%; subchondral bone edema 24-31%, 84-97%, and 50%; biceps tendon angle 60-71%, 97-100%, and 74-81%, biceps tendon-groove distance 31-47%, 90-100%, and 56-64%; long head biceps subluxation/dislocation on axial plane 49-53%, 97-100%, and 66-70%; displacement sign 74-80%, 74-100%, and 74-87%; detour sign 51-64%, 58-81%, and 62-64%; and all signs 98-100%, 32-61%, and 75-86%.

CONCLUSION

These diagnostic signs, both known and new, individually and/or in combination, provide a valid tool in the MRI diagnosis of long head biceps tendon instability.

Inter- and intra-observer reproducibility of ultrasound analysis of the long head of the biceps

INTRODUCTION

Ultrasound assessment of the long head of the biceps (LHB) is difficult. The aim of the present study was to analyze the inter- and intra-observer reproducibility of 2 ultrasound cross-sections not previously assessed: humeral head apex (image 1) and bicipital groove entrance (image 2).

HYPOTHESIS

These ultrasound cross-sectional images allow reliable and reproducible analysis of the intra-articular LHB.

MATERIAL AND METHODS

A single-center prospective study was conducted. Inter-observer reproducibility was assessed between 2 radiologists in 20 healthy shoulders (asymptomatic group) and 35 painful shoulders (symptomatic group); intra-observer reproducibility was assessed for 1 observer in 10 healthy shoulders. Quantitative parameters comprised short and long axes and transverse area, and qualitative parameters comprise echogenicity and LHB position.

RESULTS

On images 1 and 2, inter-observer agreement on the 3 quantitative parameters was good to excellent in both subject groups (p<0.05), and more precise and highly reproducible for image 1. Agreement on the 2 qualitative parameters was excellent (p<0.001). Intra-observer reproducibility results were non-significant on all parameters.

DISCUSSION

The 2 intra-articular LHB cross-sections proved reliable and reproducible in painful and in healthy shoulders. A standardized ultrasound protocol could thus enhance the precision of LHB assessment and treatment. The difficulties of LHB measurement, often related to shoulder pathology, may, however, hinder interpretation.

LEVEL OF EVIDENCE

III, prospective intra- and inter-observer study.

Diagnostic accuracy of MRI for detection of tears and instability of proximal long head of biceps tendon: an evaluation of 100 shoulders compared with arthroscopy

OBJECTIVE

To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) for detection of instability and tears of the proximal long head of biceps tendon (LHBT). To assess intraobserver and interobserver agreement.

MATERIALS AND METHODS

We performed a retrospective analysis of prospectively collected data of 100 consecutive shoulders who underwent non-contrast 1.5-T MRI prior to arthroscopic surgery due to rotator cuff injury. Images were independently analyzed by two musculoskeletal radiologists. LHBT was evaluated for presence of tearing (intact, longitudinal split, partial-thickness, or full-thickness) and position (normal, subluxated, and dislocated). Anterosuperior rotator cuff tears were also assessed. The reference standard was arthroscopic surgery. The ramp test was performed in order to evaluate LHBT stability. Diagnostic performance measures were determined and Kappa coefficients assessed agreement.

RESULTS

Concerning the detection of overall tears, sensitivity ranged from 71 to 73% and specificity was 73%. The specificity for full-thickness tears ranged from 75 to 96%. Overall displacement showed sensitivity ranging from 51 to 58% and specificity ranging from 70 to 86%. The specificity of overall displacement combined with anterosuperior rotator cuff tears ranged from 73 to 91%. Interobserver Kappa values were between 0.59 and 0.69. Intraobserver Kappa values were between 0.74 and 0.82.

CONCLUSIONS

MRI has moderate accuracy and good agreement for detection of LHBT tears and instability. There is a tendency for increased specificity for full-thickness tears and for instability in the coexistence of anterosuperior rotator cuff tears.

Biceps Tendon Sheath Injection: An Anatomical Conundrum

Objective

Long head biceps tendon peritendinous or sheath injections are routinely administered at or immediately distally to the bicipital groove. The main indication for injection remains the clinical diagnosis or treatment of biceps tendinopathy, although true inflammation of the tendon within the bicipital groove is rare. Because the tendon sheath is merely an extension of the joint cavity, it is plausible to assume that an injection into the sheath would result in intraarticular spread. Surprisingly, such an anatomical tenet has a vague confirmation in the published clinical literature. This experiment was undertaken to investigate patterns of injectate spread when peri-tendon injection at the bicipital groove is performed.

Design

An experimental cadaveric study.

Setting

An institutional clinical anatomy laboratory.

Methods

Twelve ultrasound-guided methylene blue injections of the bicep tendon sheath were performed on cadaver specimens. Dissections and gross examination of staining of the internal joint surfaces were performed. Visual confirmation of the intra- and/or extra-articular spread of the injectate was performed.

Results

In 11 specimens, injected contrast was found spreading onto the entire internal joint surface, including glenoid cartilage. One extraarticular injection was attributable to a technical issue.

Conclusions

The experiment confirmed continuity of the joint capsule and the biceps tendon sheath. These results suggest a low diagnostic utility of peritendinous injections at the level of the bicep groove. Such injections would likely result in intraarticular deposit of the injectate. Nonetheless, this approach may be utilized as an alternative simplified access to the glenohumeral joint.

Optimizing radiation dose parameters in MDCT arthrography of the shoulder: illustration of basic concepts in a cadaveric study

OBJECTIVE

To determine in a cadaveric study the lowest achievable radiation dose and optimal tube potential generating diagnostic image quality in multidetector computed tomography (MDCT) arthrography of the shoulder.

MATERIALS AND METHODS

Six shoulders from three human cadavers were scanned using a 256-MDCT system after intra-articular injection of diluted iodinated contrast material. Using six decreasing radiation dose levels (CTDI_vol: 20, 15, 10, 8, 6, and 4 mGy) and for each dose level, four decreasing tube potentials (140, 120, 100, and 80 kVp), image noise and contrast-to-noise ratio (CNR) were measured. Two independent and blinded observers assessed the overall diagnostic image quality, subjective amount of noise, and severity of artifacts according to a four-point scale. Influence of those MDCT data acquisition parameters on objective and subjective image quality was analyzed using the Kruskal-Wallis and Wilcoxon signed-rank tests, and pairwise comparisons were performed.

RESULTS

Multidetector CT protocols with radiation doses of 15 mGy or higher, combined with tube potentials of 100 kVp or higher, were equivalent in CNR to the reference 20 mGy-140 kVp protocol (all p ≥ 0.054). Above a CTDI_vol of 10 mGy and a tube potential of 120 kVp, all protocols generated diagnostic image quality and subjective noise equivalent to the 20 mGy-140 kVp protocol (all p ≥ 0.22).

CONCLUSIONS

Diagnostic image quality in MDCT arthrography of the shoulder can be obtained with a radiation dose of 10 mGy at an optimal tube potential of 120 kVp, corresponding to a reduction of up to 50% compared with standard-dose protocols, and as high as 500% compared with reported protocols in the literature.

Accuracy of MRI in diagnosing intra-articular pathology of the long head of the biceps tendon: results with a large cohort of patients

Background

It is difficult to diagnose the pathology of the long head of the biceps tendon (LHBT) clinically. This study aimed to determine the diagnostic value of standard non-enhancing magnetic resonance imaging (MRI) for detecting LHBT pathology and identify the most useful diagnostic signs on MRI.

Methods

A total of 554 patients with preoperative 3-Tesla (3 T) MRI who underwent arthroscopic surgery for rotator cuff tears were retrospectively enrolled. Abnormal signs of LHBT on MRI included diameter change, contour irregularity, and alteration of signal intensity. Arthroscopic findings were classified according to tear progress and used as a reference standard: Type I, normal tendon; Type II, hourglass-shaped hypertrophic tendon with fraying extending into the bicipital groove; Type III, partial tear involving less than 50% of tendon width at the intraarticular region without fraying in the bicipital groove; Type IV, partial tear involving more than 50% of tendon width and extending into the bicipital groove; and Type V, complete tear (cutoff) of the tendon. Using receiver operating characteristic, prediction accuracies of MRI findings were assessed compared to those of arthroscopic findings.

Results

Arthroscopic findings showed LHBT pathology in 124 (22.4%) cases. High diagnostic efficacy was achieved when ‘at least 2 abnormal signs’ was set as diagnostic criteria (sensitivity: 77.9%; specificity: 93.7%; positive predictive value: 76.3%). Types II and III lesions showed the highest sensitivities (36.8 and 66.7%, respectively) in abnormal alteration of signal intensity in the parasagittal view while Type IV showed the highest sensitivity (82.3%) in diameter change in axial view. Interobserver agreements were substantial to almost perfect, with kappa value of 0.69–0.81.

Conclusions

The standard non-enhancing 3 T MRI had a high diagnostic value in preoperative detection of LHBT pathology. Its accuracy was increased when diagnostic criterion was set as ‘2 or more abnormal signs (diameter change, contour irregularity, and alteration of signal intensity)’. The single diagnostic sign with the highest sensitivity was alteration of signal intensity in the parasagittal view.

ACR Appropriateness Criteria® Shoulder Pain-Atraumatic

Shoulder pain is one of the most common reasons for musculoskeletal-related physician visits. Imaging plays an important role in identifying the specific cause of atraumatic shoulder pain. This review is divided into two parts. The first part provides a general discussion of various imaging modalities (radiographs, arthrography, nuclear medicine, ultrasound, CT, and MRI) and their usefulness in evaluating atraumatic shoulder pain. The second part focuses on the most appropriate imaging algorithms for specific shoulder conditions including: rotator cuff disorders, labral tear/instability, bursitis, adhesive capsulitis, biceps tendon abnormalities, postoperative rotator cuff tears, and neurogenic pain. 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 include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Arthrographic Anatomy of the Biceps Tendon Sheath: Potential Implications for Selective Injection

The purpose of this investigation was to better define the anatomical features of the biceps tendon sheath, including the distance the sheath extends below the inferior margin of the subscapularis tendon and below the termination of the bony bicipital groove. A total of 110 magnetic resonance and computed tomography arthrograms performed during 1-year period at our institution were retrospectively reviewed, and the length of the biceps tendon sheath and distances from the inferior margin of the subscapularis tendon and from the termination of the bicipital groove to the inferior margin of the biceps tendon sheath were measured by 3 radiologists. The mean length of the biceps tendon sheath was 47.5mm. The mean distances from the inferior margin of the subscapularis tendon and from the inferior margin of the bicipital groove to the distal extent of the biceps tendon sheath were 24.5mm and 11.9mm, respectively. The relationships among these 3 anatomical measurements and biological confounders of sex and age were investigated while controlling for measurement variability. The anatomical relationships between the biceps tendon sheath and surrounding structures may have implications for needle placement when attempting to inject into the biceps tendon sheath for diagnostic or therapeutic purposes.

Diagnostic accuracy of 3T conventional shoulder MRI in the detection of the long head of the biceps tendon tears associated with rotator cuff tendon tears

OBJECTIVE

To evaluate the diagnostic performance (DP) of 3T (3 Tesla field strength) conventional shoulder magnetic resonance imaging (MRI) in detecting the long head of the biceps tendon (LHBT) tears in association with rotator cuff tendon tears.

MATERIALS AND METHODS

This study included 80 consecutive patients who underwent arthroscopic surgery for rotator cuff tendon tears. Two radiologists independently evaluated the preoperative 3T shoulder MRI for the presence of LHBT tears. The DP of MRI was evaluated using the results of arthroscopy as the reference standard. We also evaluated the DP of several MR signs of LHBT in detection of partial LHBT tears.

RESULTS

Arthroscopic examination revealed 35 partial and 5 complete tears. According to the results of evaluation by reviewers 1 and 2, shoulder MRI exhibited sensitivities of 77.14 and 80 % and specificities of 71.11 and 73.33 % in detection of partial LHBT tears and sensitivities of 80 and 100 % and a specificity of 100% (both) in detection of complete LHBT tears. In detecting partial LHBT tears, increased T2 signal intensity of the LHBT exhibited high sensitivities (reviewers 1 and 2; 82.85 and 80 %, respectively) and the presence of intratendinous defects or C-signs exhibited the highest specificities (reviewers 1 and 2; 95.55 and 93.33 %, respectively), followed by abnormalities in shape and outer margins of the LHBT (reviewers 1 and 2; 91.11 and 82 %; 91.11 and 86.66 %, respectively).

CONCLUSION

Non-contrast-enhanced 3T shoulder MRI is potentially highly accurate in detection of complete LHBT tears, but moderately accurate in detection of partial LHBT tears.

Accuracy of preoperative MRI in the diagnosis of disorders of the long head of the biceps tendon

OBJETIVES

To evaluate the accuracy of magnetic resonance imaging (MRI) in the detection of disorders of the long head of the biceps tendon (LHBT). The secondary objective was to investigate predictive factors for tears and instability.

METHODS

This retrospective case series involved patients undergoing shoulder arthroscopy due to rotator cuff injury. MRI was performed in a 1.5T scanner and was evaluated by a musculoskeletal radiologist. The findings were compared with those of arthroscopic inspection.

RESULTS

A total of 90 shoulders were analyzed. Regarding tears, there was 67% sensitivity and 98% specificity. Regarding instabilities, the values were 53% and 72%, respectively. Tears and fatty degeneration of the infraspinatus are predictive factors for tears of the LHBT. Tears of the subscapularis and infraspinatus, retraction of the supraspinatus and infraspinatus equal to or greater than 30mm, and fatty degeneration of the infraspinatus and subscapularis are predictive factors for instability.

CONCLUSION

Compared to arthroscopy, the shoulder MRI has a sensitivity of 67% and a specificity of 98% for the detection of complete tears of the LHBT. For instability, the values are 53% and 72%, respectively.

Comparison of image quality of shoulder CT arthrography conducted using 120 kVp and 140 kVp protocols

OBJECTIVE

To compare the image quality of shoulder CT arthrography performed using 120 kVp and 140 kVp protocols.

MATERIALS AND METHODS

Fifty-four CT examinations were prospectively included. CT scans were performed on each patient at 120 kVp and 140 kVp; other scanning parameters were kept constant. Image qualities were qualitatively and quantitatively compared with respect to noise, contrast, and diagnostic acceptability. Diagnostic acceptabilities were graded using a one to five scale as follows: 1, suboptimal; 2, below average; 3, acceptable; 4, above average; and 5, superior. Radiation doses were also compared.

RESULTS

Contrast was better at 120 kVp, but noise was greater. No significant differences were observed between the 120 kVp and 140 kVp protocols in terms of diagnostic acceptability, signal-to-noise ratio, or contrast-to-noise ratio. Lowering tube voltage from 140 kVp to 120 kVp reduced the radiation dose by 33%.

CONCLUSION

The use of 120 kVp during shoulder CT arthrography reduces radiation dose versus 140 kVp without significant loss of image quality.

Pediatric chest CT at 70 kVp: a feasibility study in 129 children

BACKGROUND

Before introducing 70-kVp settings in the low-kilovoltage strategies for pediatric examinations, it was mandatory to demonstrate, at similar dose levels, an equivalence of image quality at 70 kVp and 80 kVp.

OBJECTIVE

To assess image quality of chest CT examinations acquired at 70 kVp in comparison with standard scanning at 80 kVp.

MATERIALS AND METHODS

We prospectively evaluated 129 children with a 70-kVp scanning protocol (group 1). All scanning parameters were kept similar to those usually selected for pediatric standard 80-kVp protocols, except the milliamperage increased by a factor of 1.6 to maintain comparable radiation dose. Image quality of group 1 examinations was compared to that of a paired population scanned at 80 kVp (group 2). The noninferiority hypothesis was fixed at 10% of the mean level of image noise.

RESULTS

There was no significant difference in the mean dose length product (DLP) and the volume computed tomography dose index (CTDIvol) between the groups (DLP: 20.5 ± 5.8 mGy.cm [group 1] vs. 19.7 ± 7.6 mGy.cm [group 2]; P = 0.06) (CTDIvol: 0.8 ± 0.1 mGy [group 1] vs. 0.8 ± 0.18 mGy [group 2]; P = 0.94). The mean of differences in image noise between group 1 and group 2 examinations was -1.38 (-2.59; -0.18), verifying the noninferiority hypothesis. Subjective image quality did not significantly differ between group 1 and group 2 examinations (P = 0.18).

CONCLUSION

At equivalent radiation dose levels, 70-kVp protocols provide similar image quality to that achievable at 80 kVp.

Inappropriate requests for magnetic resonance scans of the shoulder

PURPOSE

Magnetic resonance imaging (MRI) scans are a useful investigation for some shoulder pathology. They are costly however and a significant burden on radiology departments. In most cases clinical examination, plain radiography or ultrasound scan (USS) are sufficient for a diagnosis. There are no current UK guidelines regarding MRI shoulder scan requests.

METHODS

We reviewed 100 consecutive MRI shoulder scan requests and the associated formal reports; other investigations were also assessed.

RESULTS

Overall, 56% of MRI scans were ordered inappropriately. Shoulder consultant's requests were more appropriate than other groups (70% vs. 38%. p = 0.04). Excluding shoulder consultants 63 % of scans were inappropriately ordered. Shoulder consultants were more likely to order a preceding X-ray (80% vs. 53% respectively, p = 0.03). Of those with a clinical diagnosis of cuff pathology only 29% had an USS.

CONCLUSION

A high percentage of MRI shoulder scans are performed inappropriately. Shoulder consultants are more appropriate in their ordering than other groups. If all groups performed as well 50 % less MRI scans would need to be performed.