The effectiveness of diagnostic imaging methods for the assessment of soft tissue and articular disorders of the shoulder and elbow

Quantitative assessment of fat infiltration in the rotator cuff muscles using water-fat MRI

PURPOSE

To evaluate a chemical shift-based fat quantification technique in the rotator cuff muscles in comparison with the semiquantitative Goutallier fat infiltration classification (GC) and to assess their relationship with clinical parameters.

MATERIALS AND METHODS

The shoulders of 57 patients were imaged using a 3T MR scanner. The rotator cuff muscles were assessed for fat infiltration using GC by two radiologists and an orthopedic surgeon. Sequences included oblique-sagittal T1-, T2-, and proton density-weighted fast spin echo, and six-echo gradient echo. The iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) was used to measure fat fraction. Pain and range of motion of the shoulder were recorded.

RESULTS

Fat fraction values were significantly correlated with GC grades (P < 0.0001, κ >0.9) showing consistent increase with GC grades (grade = 0, 0%-5.59%; grade = 1, 1.1%-9.70%; grade = 2, 6.44%-14.86%; grade = 3, 15.25%-17.77%; grade = 4, 19.85%-29.63%). A significant correlation between fat infiltration of the subscapularis muscle quantified with IDEAL versus 1) deficit in internal rotation (Spearman Rank Correlation Coefficient [SRC] = 0.39, 95% confidence interval [CI] 0.13-0.60, P < 0.01) and 2) pain (SRC coefficient = 0.313, 95% CI 0.049-0.536, P = 0.02) was found but was not seen between the clinical parameters and GC grades. Additionally, only quantitative fat infiltration measures of the supraspinatus muscle were significantly correlated with a deficit in abduction (SRC coefficient = 0.45, 95% CI 0.20-0.60, P < 0.01).

CONCLUSION

An accurate and highly reproducible fat quantification in the rotator cuff muscles using water-fat magnetic resonance imaging (MRI) techniques is possible and significantly correlates with shoulder pain and range of motion.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

The importance of CT for the pre-operative surgical planning in recurrent anterior shoulder instability

BACKGROUND

MRI is the current pre-operative imaging standard in recurrent anterior shoulder instability; however, CT has increasingly gained interest due to its advantages in the detection of bony glenoid defects. This study compares the value of CT imaging and MRI for pre-operative surgical planning in recurrent anterior shoulder instability.

METHODS

Between 2006 and 2009, 83 patients presented to the author's department with recurrent anterior shoulder instability. For 48 patients, both, pre-operative MRI and CT images were available. The respective patho-morphological descriptions were retrospectively compared with the intra-operative findings. The effect of each imaging technique on the pre-operative surgical planning was analyzed and the accuracy in predicting the necessity of open versus arthroscopic surgery was compared.

RESULTS

In determining the necessity of open versus arthroscopic surgery CT imaging rendered an inaccurate prediction in 4.8 % of the cases which is less than the 25.0 % calculated for MRI. (p = 0.019). MRI showed a low sensitivity (35.3 %) in the detection of significant glenoid bone defects (≥20 % of the glenoid width measured on en-face views using a best-fit circle technique) while CT imaging provided an accurate prediction of the intra-operative finding in all cases.

CONCLUSION

Despite the advantages of MRI in the detection of soft tissue damages in recurrent anterior shoulder instability CT imaging proved to be more important for pre-operative planning by prevailing in the detection of glenoid defects. Therefore, the replacement of MRI as preoperative imaging standard with CT imaging is recommended.

The posterior transtriceps approach for intra-articular elbow diagnostics, definitely not forgotten

BACKGROUND/AIMS

The elbow is among the most common joints that are aspirated and/or injected. An intra-articular approach should be a convenient and a safe procedure with minimal risk of complications. Several approaches to access the elbow joint have been outlined in the literature, but a comparative study is lacking. This study evaluates the technical feasibility of the lesser-performed posterior transtriceps approach with MR arthrography and compares it to the classic lateral radiocapitellar approach.

PATIENTS AND METHODS

Using fluoroscopy guidance, MR arthrographies of the elbow were performed in 51 consecutive patients from 2006 to 2011. A classical lateral radiocapitellar approach was performed in 29 and a posterior transtriceps approach in 22 elbows. Studies were retrospectively reviewed with special attention to the extent of extra-articular contrast extravasation. This was a level IV diagnostic study.

RESULTS

Contrast leakage occurred in 12 radiocapitellar approaches, which caused a diagnostic dilemma in one subject. There was only a minimal amount of contrast leakage in five subjects using the transtriceps approach and no diagnostic dilemmas occurred. Results show no significant differences between the approaches. No complications occurred in the posterior transtriceps group and all MR arthrographies were diagnostic.

CONCLUSIONS

The posterior transtriceps approach is a technical feasible procedure, is easy to perform, and avoids a diagnostic dilemma in presumed injuries to the lateral collateral ligament complex. Our results show a tendency of even lesser amount of contrast leakage, further promoting a more widespread usage of the posterior transtriceps approach.

Correlation of preoperative MRI and MRA with arthroscopically proven articular cartilage lesions of the elbow

OBJECTIVE

The purpose of this study was to evaluate the usefulness of magnetic resonance imaging (MRI) in detecting elbow articular cartilage injuries through comparison of preoperative MRI and magnetic resonance arthrography (MRA) with arthroscopic findings.

DESIGN

Retrospective case analysis.

SETTING

Tertiary care orthopedic private practice.

PATIENTS

Consecutive series of 31 patients presenting with elbow pain and diagnosed at arthroscopy with articular cartilage defects of the elbow. All patients had a preoperative MRI or MRA using a 1.5 T magnet.

INTERVENTIONS

Each patient had a systematic elbow arthroscopy, with careful inspection and recording of chondral injuries in 4 anatomical regions: capitellum, radius, trochlea, and ulna. Each MRI/MRA was then independently reviewed by 2 radiologists blinded to the arthroscopic findings.

MAIN OUTCOME MEASURES

The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were calculated for MRI and MRI compared with arthroscopy as the gold standard, for each of the anatomical regions.

RESULTS

The accuracy of MRI was 45% for chondral injuries of the radius, 65% for the capitellum, 20% for the ulna, and 30% for the trochlea. The accuracy of MRA was 45% for chondral injuries of the radius, 64% for the capitellum, 18% for the ulna, and 27% for the trochlea.

CONCLUSION

We conclude that the ability of MRI and MRA using a 1.5 T magnet to detect articular cartilage lesions is limited. Neither MRI nor MRA demonstrates the intraarticular surface as accurately as direct visualization with the arthroscopy. This may be improved with the use of 3 T MRI.

CLINICAL RELEVANCE

This study demonstrates that MRI and MRA with a 1.5 T magnet, as used in community practice, have limited ability to detect cartilage lesions of the elbow.

Surgeon-operated ultrasonography in a one-stop shoulder clinic

INTRODUCTION

Nearly 1 in 40 of the population seeks medical advice related to a shoulder problem every year. The majority pertain to rotator cuff pathology. Prior to intervention in such patients it is imperative to define whether the tendons are intact or torn. Ultrasonography has become an essential adjunct to clinical assessment in diagnosing rotator cuff tears. This study was designed to investigate if a surgeon using a portable ultrasonography machine in a one-stop shoulder clinic could significantly reduce the time a patient waited from initial outpatient presentation to the end of the treatment episode (be it surgery, injection or conservative management).

METHODS

A total of 77 patients were allocated to one of two groups: Group A, consisting of 37 patients who were assessed and had ultrasonography as outpatients, and Group B, consisting of 40 patients who were assessed and referred for departmental ultrasonography where appropriate. Three clear outcome groups were defined: those who required surgical repair, those who had irreparable tears and those who declined surgery.

RESULTS

For all outcomes (surgery, irreparable tears and conservative treatment), the patients in Group A all completed their clinical episodes significantly quicker than those in Group B (p<0.02). As well as the time saving benefits, there was a substantial financial saving for Group A. By performing ultrasonography in the outpatients department, those patients avoided the requirement of departmental imaging (£120) and subsequent follow-up appointments (£73) to discuss results and management, resulting in a saving of nearly £200 per patient.

CONCLUSIONS

The use of a portable ultrasonography machine by an orthopaedic surgeon can significantly reduce the time to treatment and the financial cost for patients with rotator cuff tears.

Magnetic resonance imaging in radial head fractures: most associated injuries are not clinically relevant

BACKGROUND

Recent studies report that magnetic resonance imaging (MRI) shows a high incidence of associated injuries in patients with a radial head fracture. This retrospective study describes the clinical relevance of these injuries.

MATERIALS AND METHODS

Forty patients with 42 radial head fractures underwent a MRI scan after a mean of 7.0 days after trauma and were reviewed after a mean of 13.3 months.

RESULTS

MRI showed 24 of 42 elbows had a lateral collateral ligament (LCL) lesion, 1 had a medial collateral ligament (MCL) and LCL lesion, 16 had an injury of the capitellum, 1 had a coronoid fracture, and 2 had loose osteochondral fragments. Clinical evaluation after a mean of 13.3 months showed that 3 elbows had clinical MCL or LCL laxity, of which 2 elbows had no ligamentous injuries diagnosed with MRI. One elbow with a loose osteochondral fragment showed infrequent elbow locking. The mean Mayo Elbow Performance Scale was 97.5 (range, 80-100) after a mean of 13.3 months after trauma, with no significant difference between patients with and without associated injuries (P = .8).

CONCLUSION

Most injuries found with MRI in patients with radial head fractures are not symptomatic or of clinical importance in short-term follow-up.

Comparison of 2- and 3-dimensional shoulder ultrasound to magnetic resonance imaging in a community hospital for the detection of supraspinatus rotator cuff tears with improved worktime room efficiency

PURPOSE

The purpose of this study was to evaluate whether 3-dimensional (3D) volumetric acquisition of shoulder ultrasound (US) data for supraspinatus rotator cuff tears is as sensitive when compared with conventional 2-dimensional (2D) US and routine magnetic resonance imaging (MRI), and whether there is improved workroom time efficiency when using the 3D technique compared with the 2D technique.

METHODS

In this prospective study, 39 shoulders underwent US and MRI examination of their rotator cuff to confirm the accuracy of both the 2D and 3D techniques. The difference in sensitivities was compared by using confidence interval analysis. The mean times required to obtain the 2D and 3D US data and to review the scans were compared by using a 1-tailed Wilcoxon test.

RESULTS

Sensitivity and specificity of 2D US in detecting supraspinatus full- and partial-thickness tears was 100% and 96%, and 80% and 100%, respectively, and similar values were obtained with 3D US at 100% and 100%, and 90% and 96.6%, respectively. Analysis of the confidence limits of the sensitivities showed no significant difference. The mean time (± SD) of the overall 2D examination of the shoulder, including interpretation was 10.02 ± 3.28 minutes, whereas, for the 3D examination, it was 7.08 ± 0.35 minutes. Comparison between the 2 cohorts when using a 1-tailed Wilcoxon test showed a statistically significant difference (P < .05).

CONCLUSION

3D US of the shoulder is as accurate as 2D US when compared with MRI for the diagnosis of full- and partial-thickness supraspinatus rotator cuff tears, and 3D US examination significantly reduced the time between the initial scan and the radiologist interpretation, ultimately improving workplace efficiency.

A comparison of physical examinations with musculoskeletal ultrasound in the diagnosis of biceps long head tendinitis

Provocative tests are useful in diagnosing biceps tendon tendinitis. This is the first study to establish the reliability of these tests by comparing the resuts with musculoskeletal ultrasound (US) findings. This study examined 125 patients (69 women and 56 men) and 143 shoulders with shoulder pain. Yergason's test, Speed's test and a bicipital groove tenderness test were performed and musculoskeletal US findings were used as standard reference. Biceps tendon tendinitis was diagnosed with US in 39.1% of the patients and, of those, 55.3% had coexisting rotator cuff injury. The sensitivity and specificity of Yergason's test were 32% and 78%, respectively. The sensitivity and specificity of Speed's test were 63% and 58%, respectively. In conclusion, all three tests are limited by poor sensitivity. US can be an image modality choice in diagnosing biceps pathology.

A prospective study of shoulder pain in primary care: prevalence of imaged pathology and response to guided diagnostic blocks

BACKGROUND

The prevalence of imaged pathology in primary care has received little attention and the relevance of identified pathology to symptoms remains unclear. This paper reports the prevalence of imaged pathology and the association between pathology and response to diagnostic blocks into the subacromial bursa (SAB), acromioclavicular joint (ACJ) and glenohumeral joint (GHJ).

METHODS

Consecutive patients with shoulder pain recruited from primary care underwent standardised x-ray, diagnostic ultrasound scan and diagnostic injections of local anaesthetic into the SAB and ACJ. Subjects who reported less than 80% reduction in pain following either of these injections were referred for a magnetic resonance arthrogram (MRA) and GHJ diagnostic block. Differences in proportions of positive and negative imaging findings in the anaesthetic response groups were assessed using Fishers test and odds ratios were calculated a for positive anaesthetic response (PAR) to diagnostic blocks.

RESULTS

In the 208 subjects recruited, the rotator cuff and SAB displayed the highest prevalence of pathology on both ultrasound (50% and 31% respectively) and MRA (65% and 76% respectively). The prevalence of PAR following SAB injection was 34% and ACJ injection 14%. Of the 59% reporting a negative anaesthetic response (NAR) for both of these injections, 16% demonstrated a PAR to GHJ injection. A full thickness tear of supraspinatus on ultrasound was associated with PAR to SAB injection (OR 5.02; p < 0.05). Ultrasound evidence of a biceps tendon sheath effusion (OR 8.0; p < 0.01) and an intact rotator cuff (OR 1.3; p < 0.05) were associated with PAR to GHJ injection. No imaging findings were strongly associated with PAR to ACJ injection (p ≤ 0.05).

CONCLUSIONS

Rotator cuff and SAB pathology were the most common findings on ultrasound and MRA. Evidence of a full thickness supraspinatus tear was associated with symptoms arising from the subacromial region, and a biceps tendon sheath effusion and an intact rotator cuff were associated with an intra-articular GHJ pain source. When combined with clinical information, these results may help guide diagnostic decision making in primary care.

Results of concomitant rotator cuff and SLAP repair are not affected by unhealed SLAP lesion

HYPOTHESIS

To verify the anatomic results of combined repair of a full-thickness rotator cuff tear and superior labral anterior and posterior (SLAP) lesion. In addition, we compared the anatomic and functional outcomes according to the status of the repaired SLAP lesion.

METHODS

We enrolled 61 patients who underwent cuff repair with concomitant SLAP repair and were available for both functional and radiologic outcome evaluation at least 1 year after the operation. There were 40 male and 21 female patients with a mean age of 57.4 years (range, 39-70 years). We measured various clinical outcomes and evaluated the structural outcomes of the rotator cuff and the superior labrum and rotator cuff using computed tomography arthrography at the final follow-up visit. We also evaluated the functional outcome according to anatomic healing of the superior labrum.

RESULTS

Labral healing to the bony glenoid was achieved in 49 patients (80.3%), and anatomic healing of the rotator cuff was observed in 44 patients (72.1%). The retear rate of the rotator cuff was not statistically different with respect to labral healing status. All functional outcomes improved significantly (P < .001), and there were no statistical differences in functional outcome with respect to postoperative healing of the superior labrum.

CONCLUSIONS

An unhealed SLAP lesion did not preclude the successful outcome of concomitant rotator cuff repair. Therefore, repair of a concomitant SLAP lesion may not be an essential procedure for a successful outcome of a rotator cuff repair.

Symptomatic progression of asymptomatic rotator cuff tears: a prospective study of clinical and sonographic variables

BACKGROUND

The purposes of this study were to identify changes in tear dimensions, shoulder function, and glenohumeral kinematics when an asymptomatic rotator cuff tear becomes painful and to identify characteristics of individuals who develop pain compared with those who remain asymptomatic.

METHODS

A cohort of 195 subjects with an asymptomatic rotator cuff tear was prospectively monitored for pain development and examined annually for changes in various parameters such as tear size, fatty degeneration of the rotator cuff muscle, glenohumeral kinematics, and shoulder function. Forty-four subjects were found to have developed new pain, and the parameters before and after pain development were compared. The forty-four subjects were then compared with a group of fifty-five subjects who remained asymptomatic over a two-year period.

RESULTS

With pain development, the size of a full-thickness rotator cuff tear increased significantly, with 18% of the full-thickness tears showing an increase of >5 mm, and 40% of the partial-thickness tears had progressed to a full-thickness tear. In comparison with the assessments made before the onset of pain, the American Shoulder and Elbow Surgeons scores for shoulder function were significantly decreased and all measures of shoulder range of motion were decreased except for external rotation at 90° of abduction. There was an increase in compensatory scapulothoracic motion in relation to the glenohumeral motion during early shoulder abduction with pain development. No significant changes were found in external rotation strength or muscular fatty degeneration. Compared with the subjects who remained asymptomatic, the subjects who developed pain were found to have significantly larger tears at the time of initial enrollment.

CONCLUSIONS

Pain development in shoulders with an asymptomatic rotator cuff tear is associated with an increase in tear size. Larger tears are more likely to develop pain in the short term than are smaller tears. Further research is warranted to investigate the role of prophylactic treatment of asymptomatic shoulders to avoid the development of pain and loss of shoulder function.

Correlations among mineral components, progressive calcification process and clinical symptoms of calcific tendonitis

OBJECTIVE

To establish the correlations among the mineral components, progressive calcification process and clinical symptoms of calcific tendonitis.

METHODS

The morphology of the calcified deposits on the shoulders of 28 patients with calcific tendonitis was determined by high-resolution ultrasonography. The calcified deposit from each patient was aspirated and determined by the Fourier transform infrared and Raman microspectroscopies. The curve-fitting program was applied to estimate the chemical component in the calcified deposits of calcific tendonitis.

RESULTS

The morphology of calcified deposits for 28 patients was classified into four shapes: arc shape (7 patients), fragmented/punctuate shape (4 patients), nodular shape (13 patients) and cystic shape (4 patients). These classified shapes markedly correlated with the pain levels in patients. The infrared spectra of all the calcified deposits for 28 patients were easily classified into three types in the blind study and corresponded to the formative, resting and resorptive phases in the progressive calcification process of calcific tendonitis. With the progressive calcification, the IR wavenumber at 1018 cm(-1) assigned to poorly crystalline, non-stoichiometric apatite for the formative phase was shifted to 1028 cm(-1) for the resting phase and then to 1031 cm(-1) due to matured crystalline stoichiometric apatite for the resorptive phase. The curve-fitted results revealed that calcified deposits in calcific tendonitis were composed of different quantities of A-type and B-type carbonated apatites in the three phases. A significant difference was found in carbonated apatite content among the three phases (P < 0.001).

CONCLUSIONS

The different quantities of A-type and B-type carbonated apatites determined by vibrational microspectroscopy in calcified deposits were well correlated with those of the four shapes of morphologic classification, with the three phases in the progressive calcification process and with the clinical symptoms of calcific tendonitis.

Comparison study of indirect MR arthrography and direct MR arthrography of the shoulder

OBJECTIVE

To compare the diagnostic value of indirect magnetic resonance arthrography (I-MRA) with that of direct MR arthrography (D-MRA) for labral tears, rotator cuff tears, and long head of biceps tendon (LHBT) tears using a 3-T MR unit.

MATERIALS AND METHODS

Institutional review board approval was given; written informed consent was obtained from all patients. From November 2005 to June 2006, 19 patients (eight men and 11 women; mean age, 51 years) who had undergone both I-MRA and D-MRA underwent arthroscopic surgery. Both methods were performed in fat-saturated axial, coronal oblique, and sagittal oblique T1-weighted sequences, as well as axial and coronal oblique T2-weighted sequences. Two radiologists independently and retrospectively evaluated two sets of MRA for the diagnosis of superior and anterior labral tears, subscapularis tendon (SSC), and supraspinatus-infraspinatus tendon (SSP-ISP) tears, and LHBT tears. With the arthroscopic finding as a gold standard, we analyzed statistical differences of sensitivities and specificities between two sets of MRA and inter-observer agreement was evaluated using the kappa value.

RESULTS

The sensitivity and specificity of I-MRA and D-MRA for reader 1 were 79/80% and 71/80%, respectively, for superior labral tears; 100/100% and 100/100%, respectively, for anterior labral tears; 64/75% and 64/100%, respectively, for SSC tears; 100/86% and 100/100%, respectively, for SSP-ISP tears; and 67/100% and 78/100%, respectively, for LHBT tears. Those of I-MRA and D-MRA for reader 2 were 86/80% and 71/100%, respectively, for superior labral tears; 100/83% and 100/100%, respectively, for anterior labral tears; 64/88% and 82/100%, respectively, for SSC tears; 92/86% and 100/100%, respectively, for SSP-ISP tears; and 78/90% and 89/100%, respectively, for LHBT tears. No significant differences were found between the methods. Inter-observer agreements were higher than moderate (kappa > 0.41) with both methods.

CONCLUSIONS

Based on a relatively small number of patients, no significant difference was detected between I-MRI and D-MRI with regard rotator cuff, labral, and LHBT tears.

Accuracy and Cost Comparison of Ultrasound Versus Alternative Imaging Modalities, Including CT, MR, PET, and Angiography

Ultrasound (US) has become widely used in clinical medicine for the diagnosis of a variety of disease processes. The unique ability of US to provide accurate information through an efficacious, painless, portable, and nonionizing method has expanded its role and application in diverse medical settings. Given the current economic environment and the related interest in creating the greatest value for health care expenditures, US has been evaluated to compare its clinical accuracy/efficacy and cost-effectiveness versus other imaging modalities. The following literature review reports the results of research studies aimed at comparing the accuracy/efficacy and cost of US versus alternative imaging modalities, including magnetic resonance imaging, computed tomography, contrast angiography, and single-photon emission computed tomography.