Rotator cuff lesions: signal patterns at MR imaging

Role of Magnetic Resonance Imaging (MRI) in the Diagnosis of Rotator Cuff Injuries and Correlation With Arthroscopy Findings

BACKGROUND AND AIM

The prevalent cause of shoulder pain is rotator cuff tears (RCT), which induce profound discomfort and morbidity. Hence, their detection and appropriate management become important to alleviate morbidity and enhance quality of life. Imaging has an important role in the diagnosis of such patients to guide for further management. A wide array of radiological approaches has been explored for the detection of RCT. The study aimed to assess the sensitivity (SN) and specificity (SP) of regular magnetic resonance imaging (MRI) in the diagnosis and characterization of RCT and furthermore to link the results of MRI with the arthroscopy findings. The limitations and pitfalls if any with MRI patients presenting were also addressed.

MATERIALS AND METHODS

The study was a diagnostic evaluation study conducted at the Department of Radiodiagnosis, Muslim Educational Society (MES) Medical College, Perinthalmanna, India, among individuals with RCT between December 1, 2015, and May 31, 2017. Patients who were referred for MRI and then taken up for arthroscopy were included. The findings for each tendon of rotator cuff on MRI were contrasted with that of arthroscopy, and the percentage of agreement was calculated. Additional findings relevant to the study were also noted. SN, SP, positive predictive value (PPV), and negative predictive value (NPV) of MRI were determined by taking arthroscopic findings as the gold standard.

RESULTS

The study was comprised of 36 patients assessed using MRI and arthroscopy for RCT. The study participants ranged in age from 31 to 70 years, with a mean of 52.69±8.86 years. The majority of the patients (69.4%) were between the ages of 41 and 60 years. MRI had 100% SN and SP for full-thickness supraspinatus (SS) tear, 50% SN and 100% SP for partial-thickness SS tear, 100% SN and 80% SP for full-thickness infraspinatus (IS) tear, 75% SN and 80% SP for partial-thickness IS tear, and 95% SN and 86.6% SP for subscapularis (SC) tear.

CONCLUSION

The MRI RCT investigation had a high SN, SP, and PPV compared to arthroscopy. The most frequently involved tendon reported in the present study was SS (n=35; 97.22%) followed by IS (n=32; 88.88%) and SC (n=22; 61.11%). The teres minor tendon was least commonly affected (n=0). Moreover, 61.11% (n=22) of the patients had joint effusion, 41.66% (n=15) had subacromial-subdeltoid bursal effusion, and 27.77% (n=10) had subcoracoid effusion, suggesting that RCT include joint effusion or bursal fluid. Acromioclavicular (AC) joint hypertrophy was found in 53% (n=19) of the patients, and 90% (n=17) were over 45 years old, indicating an association between age, AC joint hypertrophy, and RCT. Therefore, MRI has a good SN and SP for detecting various RCT. Therefore, it could be used to investigate a suspected RCT and should be considered a near-reference standard to arthroscopy for RCT diagnosis.

Anatomic characteristics of shoulder based on MRI accurately predict incomplete rotator cuff injuries in patients: relevance for predictive, preventive, and personalized healthcare strategies

Background and PPPM-related working hypothesis

In the diagnosis of incomplete rotator cuff injuries (IRCI), magnetic resonance imaging (MRI) and ultrasound examination often have false-positive and false-negative results, while arthroscopy is expensive, invasive, and complex. From the strategy of predictive, preventive, and personalized medicine (PPPM), shoulder anatomical characteristics based on MRI have been demonstrated to accurately predict IRCI and their clinical applicability for personalized prediction of IRCI.

Aims

This study aimed to develop and validate a nomogram based on anatomical features of the shoulder on MRI to identify IRCI for PPPM healthcare strategies.

Methods

The medical information of 257 patients undergoing preoperative MRI examination was retrospectively reviewed and served as the primary cohort. Partial-thickness rotator cuff tears (RCTs) and tendinopathy observed under arthroscopy were considered IRCI. Using logistic regression analyses and least absolute shrinkage and selection operator (LASSO), IRCI was identified among various preoperative factors containing shoulder MRI and clinical features. A nomogram was constructed and subjected to internal and external validations (80 patients).

Results

The following eight independent risk factors for IRCI were identified:AgeThe left injured sidesThe Goutallier classification of supraspinatus in oblique coronal positionThe Goutallier classification of supraspinatus in the axial positionAcromial thicknessAcromiohumeral distanceCoracohumeral distanceAbnormal acromioclavicular joint signalsThe nomogram accurately predicted IRCI in the development (C-index, 0.932 (95% CI, 0.891, 0.973)) and validation (C-index, 0.955 (95% CI, 0.918, 0.992)) cohorts. The calibration curve was consistent between the predicted IRCI probability and the actual IRCI ratio of the nomogram. The decision curve analysis and clinical impact curves demonstrated that the model had high clinical applicability.

Conclusions

Eight independent factors that accurately predicted IRCI were determined using MRI anatomical findings. These personalized factors can prevent unnecessary diagnostic interventions (e.g., arthroscopy) and can assist surgeons in implementing individualized clinical decisions in medical practice, thus addressing the goals of PPPM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-023-00333-5.

Shoulder magnetic resonance imaging findings in manual wheelchair users with spinal cord injury

Objective: To investigate the prevalence of rotator cuff and long head of the biceps pathologies in manual wheelchair (MWC) users with spinal cord injury (SCI).Design: Cross-sectional study.Setting: Outpatient clinic at a tertiary medical center.Participants: Forty-four adult MWC users with SCI (36 men and 8 women) with an average age (SD) of 42 (13) years. SCI levels ranged from C6 to L1; complete and incomplete SCI.Outcome Measures: Participants' demographic and anthropometric information, presence of shoulder pain, Wheelchair User's Pain Index (WUSPI) scores, and magnetic resonance imaging findings of shoulder pathologies including tendinopathy, tendon tears, and muscle atrophy.Results: Fifty-nine percent of the participants reported some shoulder pain. The prevalence of any tendinopathy across the rotator cuff and the long head of biceps tendon was 98%. The prevalence of tendinopathy in the supraspinatus was 86%, infraspinatus was 91%, subscapularis was 75%, and biceps was 57%. The majority of tendinopathies had mild or moderate severity. The prevalence of any tears was 68%. The prevalence of tendon tears in the supraspinatus was 48%, infraspinatus was 36%, subscapularis was 43%, and biceps was 12%. The majority of the tears were partial-thickness tears. Participants without tendon tears were significantly younger (P < 0.001) and had been wheelchair user for a significantly shorter time (P = 0.005) than those with tendon tears.Conclusion: Mild and moderate shoulder tendinopathy and partial-thickness tendon tears were highly prevalent in MWC users with SCI. Additionally, the findings of this study suggest that strategies for monitoring shoulder pathologies in this population should not be overly reliant on patient-reported pain, but perhaps more concerned with years of wheelchair use and age.

Tendon stump type on magnetic resonance imaging is a predictive factor for retear after arthroscopic rotator cuff repair

BACKGROUND

Fatty infiltration of the rotator cuff musculature increases in larger tears and is a factor in retearing. However, tearing may recur even in patients with small original tears and little fatty infiltration of the rotator cuff musculature. We devised a system to classify the rotator cuff tendon stump by magnetic resonance imaging (MRI) signal intensity and investigated prognosis-related factors associated with retear based on other MRI findings.

METHODS

We analyzed and compared the signal intensity of the rotator cuff tendon stump and deltoid on preoperative T2-weighted fat-suppressed MRI in 305 patients who underwent primary arthroscopic rotator cuff repair. We also investigated the tear size, Goutallier stage, and global fatty degeneration index.

RESULTS

In a type 1 stump, the tendon stump had a lower (darker) signal intensity than the deltoid. In type 2, the signal intensities of the tendon stump and deltoid were equivalent. In type 3, the signal intensity of the tendon stump was higher (whiter) than that of the deltoid. Multiple regression analysis of the association between retear and other parameters identified stump type (odds ratio [OR], 4.28), global fatty degeneration index (OR, 2.99), and anteroposterior tear size (OR, 1.06) as significant factors. The retear rates were 3.4% for type 1 stumps, 4.9% for type 2, and 17.7% for type 3.

CONCLUSIONS

Type 3 stumps had a significantly higher retear rate, suggesting that stump signal intensity may be an important indicator for assessing the stump's condition. Our stump classification may be useful in choosing suture techniques and postoperative therapies.

The Value of Percutaneous Shoulder Puncture with Contrast-enhanced Ultrasound in Differentiation of Rotator Cuff Tear Subtypes: A Preliminary Prospective Study

Imaging tests perform relatively well in the detection of rotator cuff tears (RCTs), exhibiting high sensitivity and specificity, mainly among larger full-thickness tears (tear width >1 cm). However, these tests are relatively less accurate in the detection of small full-thickness tears and partial-thickness tears. The purpose of this study was to determine the feasibility of percutaneous ultrasound-guided tendon lesionography (PUTL) using the SonoVue and the value of percutaneous shoulder puncture via contrast-enhanced ultrasound (CEUS)-a combination of percutaneous ultrasound-guided subacromial bursography (PUSB) and PUTL-in the detection of RCT subtypes. Conventional ultrasound (US), CEUS and magnetic resonance imaging (MRI) were performed and prospectively evaluated in 97 patients who had undergone arthroscopy because of suspected RCTs. The rates of detection of the various subtypes of RCTs using CEUS, PUSB, PUTL, US and MRI were evaluated. The RCT subtype detection rate via CEUS was significantly higher than the rates via US and MRI (96.9%, 74.2% and 76.3%, respectively), as were the detection rates for small full-thickness tears combined with partial-thickness tears (98.2%, 60.0% and 61.8%, respectively). The detection rate with PUSB was significantly higher than those with US and MRI in assessing full-thickness tears combined with bursal-side partial-thickness tears (93.9%, 65.3% and 65.3%, respectively). The detection rate with PUTL was significantly higher than those with US and MRI in assessing the corresponding subtypes (100.0%, 69.2% and 76.9%, respectively). On the basis of our findings, we consider PUTL a tolerable and feasible procedure. Percutaneous shoulder puncture using CEUS can be an effective alternative method with better diagnostic performance than US and MRI for the detection of RCT subtypes.

Arthroscopic treatment for intratendinous rotator cuff tear results in satisfactory clinical outcomes and structural integrity

PURPOSE

This study aimed to evaluate the clinical outcomes and structural integrity of arthroscopic repair of intratendinous rotator cuff tear.

METHODS

Patients who were diagnosed with an intratendinous tear but in whom conservative treatment failed were selected and underwent arthroscopic repair. Between 2008 and 2014, a total of 30 patients (6 men, 24 women; mean age, 59 ± 3.7 years) met the inclusion criteria and were followed up. The mean follow-up period was 26.3 ± 0.7 months. The results were evaluated using the University of California at Los Angeles (UCLA) score, the Society of the American Shoulder and Elbow Surgeons rating scale (ASES) questionnaire, and the visual analog scale (VAS) and range of motion (ROM) were measured preoperatively and at final follow-up. Magnetic resonance imaging (MRI) was performed preoperatively and at 6.7 ± 0.2 months postoperatively. Postoperative MRI was performed on 27 out of 30 patients and analysed using the Sugaya classification.

RESULTS

Corresponding to the preoperative MRI findings, arthroscopic findings of intratendinous tears were observed in all 30 patients. The mean active forward elevation ROM was 137.3° ± 15.4° before surgery and 168.8° ± 15.2° at the final follow-up. The internal and external rotations at abduction were 31.7° ± 5.1° and 63.0° ± 11.6° before surgery, respectively, and 60.5° ± 8.0° and 75.2° ± 10.8° after surgery, respectively. The UCLA score improved from of 20.1 ± 7.4 points preoperative to 28.4 ± 5.5 points at the final follow-up. The ASES score improved from 55.7 ± 15.3 points preoperative to 82.6 ± 9.7 points postoperatively. The VAS for pain score decreased from 6.4 ± 1.2 points preoperative to 1.6 ± 0.9 points postoperative. Satisfactory outcomes (excellent/good) in terms of UCLA and ASES scores were observed in 29 of 30 patients. Based on Sugaya classification, grades I, II, and III structural integrities were observed in 9, 14, and 4 patients, respectively.

CONCLUSIONS

Successful clinical outcomes and structural integrity can be achieved with arthroscopic repair of intratendinous rotator cuff tears involving more than half thickness (> 50%). Therefore, arthroscopic repair is a practical next treatment option for patients with intratendinous rotator cuff tears in whom conservative treatment fails.

LEVEL OF EVIDENCE

IV.

The epidemiology of MRI detected shoulder injuries in athletes participating in the Rio de Janeiro 2016 Summer Olympics

BACKGROUND

To use Magnetic Resonance Imaging (MRI) to characterize the severity, location, prevalence, and demographics of shoulder injuries in athletes at the Rio de Janeiro 2016 Summer Olympic Games.

METHODS

This was a retrospective analysis of all routine shoulder MRIs obtained from the Olympic Village Polyclinic during the Rio 2016 Summer Olympics. Imaging was performed on 1.5 T and 3 T MRI, and interpretation was centrally performed by a board-certified musculoskeletal radiologist. Images were assessed for tendon, muscle, bone, bursal, joint capsule, labral, and chondral abnormality.

RESULTS

A total of 11,274 athletes participated in the Games, of which 55 (5%) were referred for a routine shoulder MRI. Fifty-three (96%) had at least two abnormal findings. Seven (13%) had evidence of an acute or chronic anterior shoulder dislocation. Forty-nine (89%) had a rotator cuff partial tear and / or tendinosis. Subacromial / subdeltoid bursitis was present in 29 (40%). Thirty (55%) had a tear of the superior labrum anterior posterior (SLAP).

CONCLUSION

Our study demonstrated a high prevalence of both acute and chronic shoulder injuries in the Olympic athletes receiving shoulder MRI. The high rates of bursal, rotator cuff, and labral pathology found in these patients implies that some degree of glenohumeral instability and impingement is occurring, likely due to fatigue and overuse of the dynamic stabilizers. Future studies are needed to better evaluate sport-specific trends of injury.

Supraspinatus muscle occupation ratio predicts rotator cuff reparability

BACKGROUND

We wished to determine the correlation between supraspinatus muscle occupation ratio and reparability of rotator cuff muscles and that of each occupation ratio with 1-muscle, 2-muscle, and 3-muscle rotator cuff injury.

METHODS

We evaluated 170 patients (average age, 62.3 [40-83] years) with complete (type II) or incomplete (type III) rotator cuff repair by arthroscopy. Type II repair was defined as complete repair but less optimal coverage of the entire medial-lateral footprint. Type III repair was defined as incomplete repair; a small portion (<10 mm) of the humeral head is exposed. Patients were divided into 2 groups: 96 and 74 patients who underwent type II and type III repair, respectively. Patients were also categorized into 4 groups: isolated supraspinatus tears, supraspinatus and infraspinatus tears, supraspinatus and subscapularis tears, and tears in all 3 muscles. Supraspinatus muscle atrophy was evaluated by the occupation ratio on the most lateral T1-weighted sagittal oblique view in which the scapular spine contacted the scapular body. The supraspinatus muscle occupation ratio was measured by 2 independent observers.

RESULTS

On magnetic resonance imaging, the supraspinatus muscle occupation ratio was significantly different between the completely repaired and incompletely repaired groups. The mean occupation ratio of the completely repaired group (42.39 ± 10.1) was significantly higher than that of the incompletely repaired group (36.64 ± 6.94). The cutoff value of the supraspinatus muscle occupation ratio (complete to incomplete repair) was 41. The supraspinatus muscle occupation ratio significantly decreased as the tear increased (P < .001).

CONCLUSION

A supraspinatus muscle occupation ratio of <41 can be the cutoff value for greater tuberosity coverage vs. incomplete coverage. There was a significant correlation between tear pattern and supraspinatus muscle atrophy ratio. The supraspinatus tear group had the lowest degree of muscle atrophy.

A Prospective Comparative Study of High Resolution Ultrasound and MRI in the Diagnosis of Rotator Cuff Tears in a Tertiary Hospital of North India

Background

To evaluate the accuracy of high resolution ultrasound (USG) and MRI in the diagnosis of rotator cuff tears (RCT) and to determine if high resolution USG compares favorably in sensitivity and specificity to MRI in the diagnosis of rotator cuff injury.

Material/Methods

In this prospective comparative study, 40 patients with clinically suspected rotator cuff tears underwent both ultrasound and MRI of the shoulder. Out of these 40 patients, 31 patients who had positive findings for rotator cuff tears on ultrasound and/or MRI were finally included in the study while the remaining 9 patients with negative or unrelated findings were excluded. The USG and MRI were interpreted by two radiologists experienced in musculoskeletal radiology and blinded to findings of each other. Comparison was done using MRI as a standard reference.

Results

The agreement between USG and MRI for diagnosis of RCTs was statistically excellent; USG showed a sensitivity of 86.7% and a specificity of 100% for full-thickness tears, and a sensitivity of 89.7% and a specificity of 98.8% for partial-thickness tears; observed accuracy for full thickness tears was 98.4% and 95.9% for partial thickness tears. The Kappa coefficient of association was 0.91 for full thickness tears and 0.90 for partial thickness tears.

Conclusions

Considering the comparable diagnostic accuracy of USG and MRI, the former modality can be used as a first-line investigation for diagnosis of RCT. MRI should be used secondarily as a problem-solving tool either following an equivocal shoulder USG or for delineation of anatomy in cases where surgical correction is needed.

Rotator cuff tears: Review of epidemiology, clinical assessment and operative treatment

Rotator cuff tears (RTCs) are the most common cause of shoulder disability. There has been a proportional increase in the prevalence of RCT in accordance with the rising trend of an ageing population. In this article we review the current literature encompassing RCT epidemiology, risk factors and aetiopathogenesis. We also summarize the current diagnostic modalities, treatment options, rehabilitation and outcomes.

[Systematics of injuries of the rotator cuff and biceps tendon]

PERFORMANCE

Injuries of the rotator cuff and the biceps tendon demonstrate different patterns, which can be recognized clinically and radiologically.

ACHIEVEMENTS

These patterns are impingement syndrome with additional trauma, isolated trauma of the rotator cuff and shoulder dislocation causing rotator cuff tears. Furthermore, it is clinically crucial to evaluate the extent of a rotator cuff injury.

PRACTICAL RECOMMENDATION

Magnetic resonance imaging (MRI) is the modality of choice to differentiate these patterns.

Clinical Features Associated with Frozen Shoulder Syndrome in Parkinson's Disease

Background. Frozen shoulder syndrome is a common musculoskeletal disease of idiopathic Parkinson's disease (PD) that causes long-term pain and physical disability. A better understanding of the associated factors can help identify PD patients who will require prevention to improve their quality of life. Methodology. This prospective study evaluated 60 shoulders of 30 PD patients. Correlation analysis was used to evaluate the relationships between clinical factors and shoulder sonography findings. Results. Frozen shoulder syndrome was found in 14 of 30 PD patients affecting 19 shoulders, including bilateral involvement in five and unilateral involvement in nine. There was a significant positive correlation between the parameters of sonography findings and frozen shoulder syndrome (i.e., thickness of bicipital effusion and tendon thickness of the subscapularis and supraspinatus) and mean ipsilateral Unified Parkinson's Disease Rating Scale (UPDRS) III and its subscores (tremor, rigidity, and bradykinesia scores). Conclusions. Higher ipsilateral UPDRS and subscores are associated with increased effusion around the biceps tendon, with increased tendon thickness of subscapularis and supraspinatus. Preventing frozen shoulder syndrome in the high-risk PD group is an important safety issue and highly relevant for their quality of life.

The effect of percutaneous ultrasound-guided subacromial bursography using microbubbles in the assessment of subacromial impingement syndrome: initial experience

OBJECTIVE

The purpose of this study was to determine the feasibility and the value of percutaneous ultrasound-guided subacromial bursography (PUSB) with contrast-enhanced ultrasound (CEUS) for assessment of rotator cuff tears.

METHODS

Between January 2012 and September 2014, 2-D US and PUSB were prospectively performed in 135 patients with suspected rotator cuff tears from among 2,169 patients with clinically diagnosed subacromial impingement syndrome. Sixty-three patients who had undergone arthroscopy were included. The PUSB findings were compared with those from 2-D US using the McNemar test, with arthroscopy as a standard.

RESULTS

Of a total of 19 full-thickness tears (FTTs), 2-D US correctly diagnosed 12 and PUSB correctly diagnosed 18 (P = 0.031). With regard to partial-thickness tears, 2-D US correctly diagnosed 31 and PUSB 35 of a total of 41 tears (P = 0.375).Accuracy in diagnosing FTTs was 81.0 % for 2-D US and 98.4 % for PUSB. 2-D US and PUSB yielded sensitivity of 63.2 % and 94.7 %, respectively, for full-thickness tears, with specificity of 88.6 % and 100.0 %, respectively.

CONCLUSIONS

PUSB is a safe and feasible procedure, with greater sensitivity and specificity than 2D US in diagnosing FTTs As such, PUSB improves the value of ultrasound for assessing rotator cuff pathology.

KEY POINTS

• PUSB allows new application of CEUS and offers a new form of bursography. • PUSB appears to facilitate diagnosis of full -thickness rotator cuff tears. • PUSB outlines the rotator cuff tears more clearly than 2-D US.

Intratendinous rotator cuff tears: prevalence and clinical and radiological outcomes of arthroscopically confirmed intratendinous tears at midterm follow-up

BACKGROUND

Intratendinous tears of the rotator cuff are rare, and little has been written about them.

PURPOSE

To investigate the prevalence and clinical and radiological outcomes of arthroscopically confirmed intratendinous tears treated with transtendon suture bridge repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Included in the study were 33 patients (16 male, 17 female; mean age, 53.4 years) with arthroscopically confirmed intratendinous tears treated with transtendon suture bridge repair from March 2006 to July 2012. A history of trauma was found in 10 cases (30.3%). The dominant arm was involved in 26 cases (78.8%). The mean follow-up duration was 56 months. Preoperatively, a thorough physical examination was performed; at final follow-up, shoulder range of motion (ROM) in forward flexion, abduction, external rotation (ER) at the side, and internal rotation (IR) at the back was noted, and clinical outcomes (American Shoulder and Elbow Surgeons [ASES] score; University of California, Los Angeles [UCLA] score; visual analog scale [VAS] for pain; and Simple Shoulder Test [SST]) were recorded and compared with the preoperative data. Postoperative magnetic resonance imaging (MRI) was performed at 6 months to investigate rotator cuff healing status and repair integrity.

RESULTS

The prevalence of arthroscopically confirmed intratendinous tears was 4.7% among all arthroscopically treated partial-thickness rotator cuff tears. Impingement signs were positive in most of the patients (positive Hawkins-Kennedy test result in 78.8%, positive Neer sign in 66.7%, and either positive Hawkins-Kennedy test result or Neer sign in 84.8%). At final follow-up, mean ASES, UCLA, VAS, and SST scores improved significantly from a preoperative mean of 51.4, 18.9, 6.0, and 5.4, respectively, to a postoperative mean of 90.6, 32.9, 1.4, and 10.8, respectively (P < .001). According to the UCLA rating scale, outcomes were excellent in 17, good in 13, and fair in 3 cases. Shoulder ROM in forward flexion, abduction, ER at the side, and IR at the back improved from a preoperative mean of 135°, 129°, 25°, and L2, respectively, to a postoperative mean of 161°, 160°, 29°, and T10, respectively (P < .001 for all except ER). As per the Sugaya classification, on postoperative MRI, type I healing status was found in 10 (30.3%), type II in 18 (54.5%), and type III in 2 (6.1%) cases. None of the patients showed any evidence of retears.

CONCLUSION

Transtendon suture bridge repair yielded satisfactory clinical and radiological outcomes in patients with intratendinous rotator cuff tears.

Reliability of magnetic resonance imaging assessment of rotator cuff: the ROW study

BACKGROUND

Physiatrists encounter patients with rotator cuff disorders, and imaging is frequently an important component of their diagnostic assessment. However, there is a paucity of literature on the reliability of magnetic resonance imaging (MRI) assessment between shoulder specialists and musculoskeletal radiologists.

OBJECTIVE

We assessed inter- and intrarater reliability of MRI characteristics of the rotator cuff.

DESIGN

Cross-sectional secondary analyses in a prospective cohort study.

SETTING

Academic tertiary care centers.

PATIENTS

Subjects with shoulder pain were recruited from orthopedic and physiatry clinics.

METHODS

Two shoulder-fellowship-trained physicians (a physiatrist and a shoulder surgeon) jointly performed a blinded composite MRI review by consensus of 31 subjects with shoulder pain. Subsequently, MRI was reviewed by one fellowship-trained musculoskeletal radiologist.

MAIN OUTCOME MEASUREMENTS

We calculated the Cohen kappa coefficients and percentage agreement among the 2 reviews (composite review of 2 shoulder specialists versus that of the musculoskeletal radiologist). Intrarater reliability was assessed among the shoulder specialists by performing a repeated blinded composite MRI review. In addition to this repeated composite review, only one of the physiatry shoulder specialists performed an additional review.

RESULTS

Interrater reliability (shoulder specialists versus musculoskeletal radiologist) was substantial for the presence or absence of tear (kappa 0.90 [95% confidence interval {CI}, 0.72-1.00]), tear thickness (kappa 0.84 [95% CI, 0.70-0.99]), longitudinal size of tear (kappa 0.75 [95% CI, 0.44-1.00]), fatty infiltration (kappa 0.62 [95% CI, 0.45-0.79]), and muscle atrophy (kappa 0.68 [95% CI, 0.50-0.86]). There was only fair interrater reliability of the transverse size of tear (kappa 0.20 [95% CI, 0.00-0.51]). The kappa for intrarater reliability was high for tear thickness (0.88 [95% CI, 0.72-1.00]), longitudinal tear size (0.61 [95% CI, 0.22-0.99]), fatty infiltration (0.89 [95% CI, 0.80,-0.98]), and muscle atrophy (0.87 [95% CI, 0.76-0.98]). Intrarater reliability for the individual shoulder specialist was similar to that of the composite reviews.

CONCLUSIONS

There was high interrater and intrarater reliability for most findings on shoulder MRI. Analysis of our data supports the reliability of MRI assessment by shoulder specialists for rotator cuff disorders.

MR versus MR arthrography in detection of supraspinatus tendon tears in patients without previous shoulder surgery

PURPOSE

We report the prevalence of supraspinatus tendon tears seen on MR arthrography that are not seen on conventional MR exam in the same patient population.

MATERIALS AND METHODS

A total of 150 consecutive conventional shoulder MR and MR arthrography exams performed on the same patients who went on to arthroscopy were reviewed retrospectively by consensus reading of two musculoskeletal radiologists. Full-thickness supraspinatus tendon tears were assessed. None of the patients had previous shoulder surgery.

RESULTS

There were 113 full-thickness supraspinatus tendon tears seen on conventional MR exam while there were 119 full-thickness supraspinatus tendon tears seen on MR arthrography. The six additional full-thickness supraspinatus tendon tears seen on MR arthrography but not seen on conventional MR exam were confirmed at arthroscopy.

CONCLUSIONS

Some full-thickness supraspinatus tendon tears are not seen on conventional MR exam but are seen on MR arthrography. This is most likely due to fibrosis at the supraspinatus tendon tear site simulating an intact tendon on conventional MR.

Magnetic resonance imaging, magnetic resonance arthrography and ultrasonography for assessing rotator cuff tears in people with shoulder pain for whom surgery is being considered

BACKGROUND

Shoulder pain is a very common symptom. Disorders of the rotator cuff tendons due to wear or tear are among the most common causes of shoulder pain and disability. Magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA) and ultrasound (US) are increasingly being used to assess the presence and size of rotator cuff tears to assist in planning surgical treatment. It is not known whether one imaging method is superior to any of the others.

OBJECTIVES

To compare the diagnostic test accuracy of MRI, MRA and US for detecting any rotator cuff tears (i.e. partial or full thickness) in people with suspected rotator cuff tears for whom surgery is being considered.

SEARCH METHODS

We searched the Cochrane Register of Diagnostic Test Accuracy Studies, MEDLINE, EMBASE, and LILACS from inception to February 2011. We also searched trial registers, conference proceedings and reference lists of articles to identify additional studies. No language or publication restrictions were applied.

SELECTION CRITERIA

We included all prospective diagnostic accuracy studies that assessed MRI, MRA or US against arthroscopy or open surgery as the reference standard, in people suspected of having a partial or full thickness rotator cuff tear. We excluded studies that selected a healthy control group, or participants who had been previously diagnosed with other specific causes of shoulder pain such as osteoarthritis or rheumatoid arthritis. Studies with an excessively long period (a year or longer) between the index and reference tests were also excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data on study characteristics and results of included studies, and performed quality assessment according to QUADAS criteria. Our unit of analysis was the shoulder. For each test, estimates of sensitivity and specificity from each study were plotted in ROC space and forest plots were constructed for visual examination of variation in test accuracy. Meta-analyses were performed using the bivariate model to produce summary estimates of sensitivity and specificity. We were unable to formally investigate potential sources of heterogeneity because of the small number of studies.

MAIN RESULTS

We included 20 studies of people with suspected rotator cuff tears (1147 shoulders), of which six evaluated MRI and US (252 shoulders), or MRA and US (127 shoulders) in the same people. Many studies had design flaws, with the potential for bias, thus limiting the reliability of their findings. Overall, the methodological quality of the studies was judged to be low or unclear. For each test, we observed considerable heterogeneity in study results, especially between studies that evaluated US for the detection of full thickness tears and studies that evaluated MRA for the detection of partial thickness tears. The criteria for a positive diagnostic test (index tests and reference standard) varied between studies.Meta-analyses were not possible for studies that assessed MRA for detection of any rotator cuff tears or partial thickness tears. We found no statistically significant differences in sensitivity or specificity between MRI and US for detecting any rotator cuff tears (P = 0.13), or for detecting partial thickness tears (P = 1.0). Similarly, for the comparison between MRI, MRA and US for detecting full thickness tears, there was no statistically significant difference in diagnostic performance (P = 0.7). For any rotator cuff tears, the summary sensitivity and specificity were 98% (95% CI 92% to 99%) and 79% (95% CI 68% to 87%) respectively for MRI (6 studies, 347 shoulders), and 91% (95% CI 83% to 95%) and 85% (95% CI 74% to 92%) respectively for US (13 studies, 854 shoulders). For full thickness tears, the summary sensitivity and specificity were 94% (95% CI 85% to 98%) and 93% (95% CI 83% to 97%) respectively for MRI (7 studies, 368 shoulders); 94% (95% CI 80% to 98%) and 92% (95% CI 83% to 97%) respectively for MRA (3 studies, 183 shoulders); and 92% (95% CI 82% to 96%) and 93% (95% CI 81% to 97%) respectively for US (10 studies, 729 shoulders).Because few studies were direct head-to-head comparisons, we could not perform meta-analyses restricted to these studies. The test comparisons for each of the three classifications of the target condition were therefore based on indirect comparisons which may be prone to bias due to confounding.

AUTHORS' CONCLUSIONS

MRI, MRA and US have good diagnostic accuracy and any of these tests could equally be used for detection of full thickness tears in people with shoulder pain for whom surgery is being considered. The diagnostic performance of MRI and US may be similar for detection of any rotator cuff tears. However, both MRI and US may have poor sensitivity for detecting partial thickness tears, and the sensitivity of US may be much lower than that of MRI. The strength of evidence for all test comparisons is limited because most studies were small, heterogeneous and methodologically flawed, and there were few comparative studies. Well designed studies that directly compare MRI, MRA and US for detection of rotator cuff tears are needed.

Delayed early passive motion is harmless to shoulder rotator cuff healing in a rabbit model

BACKGROUND

Postoperative passive motion is the most widely accepted rehabilitation protocol after rotator cuff repair; however, a rotator cuff retear remains a frequent surgical complication. Clinical outcomes indicate that early passive motion is harmless to rotator cuff healing, but no laboratory evidence supports this proposition.

HYPOTHESES

(1) Immediate postoperative immobilization improves rotator cuff healing in rabbits. (2) Early passive motion after short-term immobilization does not harm rotator cuff healing in rabbits.

STUDY DESIGN

Controlled laboratory study.

METHODS

An injury to the supraspinatus tendon was created and repaired in 90 New Zealand White rabbits, after which they were randomly separated into 3 groups: (1) nonimmobilization (NI; n = 30), (2) continuous immobilization (IM; n = 30), and (3) immobilization with early passive motion (IP; n = 30). At 3, 6, and 12 weeks postoperatively, 5 rabbits from each group were sacrificed for histological evaluation, biomechanical testing, and magnetic resonance imaging.

RESULTS

The histological study demonstrated better postoperative healing in the IM and IP groups, with clusters of chondrocytes accumulated at the tendon-bone junction. Magnetic resonance imaging illustrated that the tendon-bone junction was intact in the IM and IP groups. The magnetic resonance quantification analysis showed that the signal-to-noise quotient (SNQ) of the NI group was not significantly higher than that of the immobilization groups at 3 weeks (P = .232) or 6 weeks (P = .117), but it was significantly different at 12 weeks (NI vs IM, P = .006; NI vs IP, P = .009). At 12 weeks, the failure load was significantly higher in the IM and IP groups than in the NI group (NI vs IM, P = .002; NI vs IP, P = .002), but no difference was found between the IM and IP groups (P = .599).

CONCLUSION

Immediate postoperative immobilization led to better tendon-bone healing than immediate postoperative mobilization, and under immobilization, early passive motion was harmless to tendon-bone healing in this study.

CLINICAL RELEVANCE

The results have an implication in supporting the rehabilitation protocol of early passive motion after rotator cuff repair.

Predictors of success of corticosteroid injection for the management of rotator cuff disease

BACKGROUND

The use of subacromial corticosteroid injection (CSI) to treat rotator cuff tendinopathy is controversial. We hypothesized that characteristics such as activity level, American Shoulder and Elbow Surgeons (ASES) score, duration of symptoms, and status of the rotator cuff may be prognostic factors for resolution of symptoms postinjection.

METHODS

During a 12-month period, consecutive patients with rotator cuff disease were analyzed. Patients received subacromial CSI, oral NSAIDs, and physical therapy. Baseline ASES score, simple shoulder test, an activity scale, and demographic data were recorded. Patients who remained symptomatic and were indicated for surgery were considered failures. Patients that did not undergo surgery were reassessed after a minimum of 1 year.

RESULTS

Forty-nine patients met our criteria. Follow-up was obtained for 81.6%. Sixteen cases (40%) failed conservative treatment at final follow-up (22.4 ± 11 months). CSI were successful in 76.2% of males and 45% of females (p = 0.04). Full-thickness tears were present in 8% of the patients with symptom resolution and 25% of those that failed conservative treatment (p = 0.29). No significant difference was found in age, hand dominance, duration of symptoms, or any of the scoring systems.

CONCLUSION

It is difficult to predict outcomes after CSI. Our treatment strategy showed a 40% failure rate.

MDCT arthrography of the shoulder with datasets of isotropic resolution: indications, technique, and applications

OBJECTIVE

The purposes of this review are to summarize the indications for MDCT arthrography of the shoulder, highlight the features of MDCT acquisition, and describe the normal and abnormal MDCT arthrographic appearances of the shoulder.

CONCLUSION

MDCT arthrography is a valid alternative for shoulder imaging of patients with contraindications to MRI or after failed MRI. MDCT arthrography is accurate for assessment of a variety of shoulder abnormalities and, with further validation, may become the imaging test of choice for evaluation of the postoperative shoulder.

Magnetic resonance imaging of rotator cuff disease and external impingement

Magnetic resonance (MR) imaging plays a major role in helping to identify rotator cuff disease and in demonstrating the pathology associated with external impingement. Many surgeons rely on MR imaging to assist in decision making and presurgical planning for patients with rotator cuff pain. This article reviews the etiology of external impingement and rotator cuff tears, and describes the MR imaging appearance of the normal and the pathologic rotator cuffs. It focuses on the supraspinatus tendon because this is the tendon involved in 95% of rotator cuff tears.

Current imaging of the rotator cuff

Rotator cuff pathology is a common cause of shoulder pain, and imaging plays a major role in the management of shoulder problems. General radiography may be useful as an initial screening test particularly in trauma and arthritis. Musculoskeletal ultrasound and magnetic resonance imaging are the most suitable modalities for the investigation of the rotator cuff, having high sensitivities and specificities for full-thickness tears. Musculoskeletal ultrasound and magnetic resonance imaging are less accurate in the detection of partial-thickness tears with greater observer variability. This article reviews the normal and pathologic imaging features of the rotator cuff and highlights the potential usefulness and limitations of various imaging modalities in the assessment of the tendon and the potential impact of imaging findings on clinical patient care.

MRI versus radiography of acromioclavicular joint dislocation

OBJECTIVE

Acromioclavicular joint injuries are usually diagnosed by clinical and radiographic assessment with the Rockwood classification, which is crucial for treatment planning. In view of the implementation of MRI for visualization of the acromioclavicular joint, the purpose of this study was to describe the MRI findings of acromioclavicular joint dislocation in comparison with the radiographic findings.

SUBJECTS AND METHODS

Forty-four patients with suspected unilateral acromioclavicular joint dislocation after acute trauma were enrolled in this prospective study. All patients underwent digital radiography and 1-T MRI with a surface phased-array coil. MRI included coronal proton density-weighted turbo spin-echo and coronal 3D T1-weighted fast field-echo water-selective sequences. The Rockwood classification was used to assess acromioclavicular joint injuries at radiography and MRI. An adapted Rockwood classification was used for MRI evaluation of the acromioclavicular joint ligaments. The classifications of acromioclavicular joint dislocations diagnosed with radiography and MRI were compared.

RESULTS

Among 44 patients with Rockwood type I-IV injuries on radiographs, classification on radiographs and MR images was concordant in 23 (52.2%) patients. At MRI, the injury was reclassified to a less severe type in 16 (36.4%) patients and to a more severe type in five (11.4%) patients. Compared with the findings according to the original Rockwood system, with the adapted system that included MRI findings, additional ligamentous lesions were found in 11 (25%) patients.

CONCLUSION

In a considerable number of patients, the MRI findings change the Rockwood type determined with radiography. In addition to clinical assessment and radiography, MRI may yield important findings on ligaments that may influence management.

High-resolution magnetic resonance imaging of rotator cuff tears using a microscopy coil: noninvasive detection without intraarticular contrast material

PURPOSE

The aim of this study was to evaluate the feasibility of high-resolution magnetic resonance imaging (MRI) using a microscopy coil for the diagnosis of rotator cuff tears by comparing the method to conventional MRI and MRI arthrography.

MATERIALS AND METHODS

A total of 68 shoulders were prospectively studied using a 1.5-T MRI unit. Conventional MRI scans were obtained with a surface coil and high-resolution MRI scans with a microscopy coil. MRI arthrography was performed in 28 shoulders using a surface coil. MRI evaluation of tears of rotator cuff tendons was compared with arthroscopic findings and surgical results.

RESULTS

The surgery revealed 40 full-thickness tears, 13 partial-thickness tears, and 15 intact cuffs. In all, 35 (88%) full-thickness tears were correctly diagnosed on conventional MRI and 40 (100%) on high-resolution MRI. MR arthrography delineated 11 of 12 (92%) full-thickness tears. Altogether, 5 (38%) of the partial-thickness tears were detected on conventional MRI, and 12 (92%) were clearly demonstrated on high-resolution MRI. MRI arthrography depicted three (60%) of five partial-thickness tears. High-resolution MRI showed higher sensitivity than conventional MRI (P < 0.05) and had values equivalent to those of MRI arthrography for diagnosing partial-thickness tears.

CONCLUSION

High-resolution MRI with a microscopy coil is a feasible, noninvasive technique for diagnosing rotator cuff tears.

The Shoulder Pain due to Metastatic Breast Cancer -A Case Report-

A rotator cuff tear causes shoulder pain and limits movement of the shoulder joint. A chronic degenerative change or impingement is the reason for a rotator cuff tear. Diagnosis is made based on medical history and, physical and radiological examinations. Other causes of shoulder pain include calcific tendinitis, degenerative arthropathy, joint dislocation, fracture, and primary or metastatic neoplasm. However, metastatic cancer in the shoulder joint is difficult to diagnosis. We experienced a case in which a 46-year-old female patient complained of left shoulder pain and limited joint mobility, and these symptoms were due to metastatic breast cancer in the shoulder.

Surgical treatment of confirmed intratendinous rotator cuff tears: retrospective analysis after an average of eight years of follow-up

HYPOTHESIS

This study evaluated clinical features, diagnostic techniques, and summarized the results of open repair in a series of surgically confirmed cases of intratendinous rotator cuff tears.

MATERIALS AND METHODS

Between 1986 and 1999, 19 patients (17 men and 2 women) with intratendinous rotator cuff tears underwent surgery. Clinical findings, diagnostic results, and surgical findings were evaluated. The shoulder scores of the Japanese Orthopaedic Association (JOA) and the American Shoulder and Elbow Surgeons (ASES) were used to assess recovery at an average of 92 months (range, 31-231 months).

RESULTS

All patients had symptoms consistent with rotator cuff tendonitis. History of overt trauma was noted in 16 (84.2%). Neither ultrasound nor magnetic resonance imaging proved reliable for preoperative diagnosis. Surgery was performed if at least 6 months of conservative treatment, such as rest, heat, and physical therapies, failed. The definitive diagnosis was established intraoperatively with a longitudinal split along the fibers of the supraspinatus tendon. None of the intratendinous lesions had communication to the subacromial bursa or the glenohumeral joint. Excision of the intratendinous tear and repair resulted in improvement in pain and total scores of both JOA (66.8 vs 94.1) and ASES (37.1 vs 91.0).

CONCLUSIONS

Intratendinous rotator cuff tears were difficult to diagnose preoperatively. Our data suggest that conservative treatment failed, anterior acromioplasty and excision of the diseased portion of the tendon, followed by tenorrhaphy, proved effective. Satisfactory outcomes were achieved in 18 patients (94.7%) in this series.

Supraspinatus tendon tears: comparison of 3D US and MR arthrography with surgical correlation

OBJECTIVE

The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard.

MATERIALS AND METHODS

In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small (<1 cm), medium (1-3 cm), and large (>3 cm).

RESULTS

The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears.

CONCLUSION

Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears.

Magnetic resonance imaging signal abnormalities in enthesopathy of the extensor carpi radialis longus origin

PURPOSE

Some surgeons use magnetic resonance imaging (MRI) findings in patients with enthesopathy of the extensor carpi radialis brevis (ECRB) origin (commonly referred to as lateral epicondylitis) to plan and justify surgical treatment. Overinterpretation of defects of the origin of the ECRB or associated abnormalities of the lateral collateral ligament (LCL) could affect decision-making. We tested the hypothesis that patients with MRI signal abnormalities consistent with enthesopathy of the ECRB are equally likely to have findings consistent with an ECRB defect or LCL abnormality whether they are being evaluated as part of preoperative planning for lateral elbow pain or for an elbow condition that does not feature lateral elbow pain.

METHODS

For each of 24 consecutive patients with enthesopathy of the ECRB who had MRI for preoperative evaluation, we selected 2 age- and gender-matched controls from a list of patients who had an elbow MRI to evaluate other elbow problems. The origin of the ECRB and the LCL were specifically evaluated.

RESULTS

Patients diagnosed with enthesopathy of the ECRB were significantly more likely than control patients to have signal changes consistent with enthesopathy of the ECRB origin (24 of 24 vs 9 of 48; p < .001). The proportion of patients with a partial thickness defect of the ECRB origin (14 of 24 vs 4 of 9) was comparable between patients diagnosed with enthesopathy of the ECRB origin and controls. Signal changes in the LCL were comparable in patients diagnosed with enthesopathy of the ECRB origin and control patients (8 of 24 vs 2 of 9; p = .27), and no patient had clinical evidence of instability.

CONCLUSIONS

Use of MRI in the management of patients with enthesopathy of the ECRB origin merits further study.

[Imaging in evaluating rotator cuff tears]

Diagnostic imaging in a patient with shoulder pain should be used only after a comprehensive clinical evaluation of the shoulder. X-ray and ultrasonography are the basic diagnostic tools; computed tomography and magnetic resonance imaging (MRI) should be used only with certain indications. Ultrasonography and MRI have comparable accuracy for identifying and measuring full-thickness rotator cuff tears, but the accuracy for identifying partial-thickness still needs to be improved. MR arthrography has significantly improved sensitivity and specificity for partial-thickness tears of the cuff. Only ultrasound provides a real-time examination tool during shoulder movements. Moreover, dynamic ultrasonography can assess the contraction patterns of the supraspinatus and infraspinatus muscles, which may improve decision making in the treatment of shoulder diseases. In depicting fatty atrophy of the supraspinatus and infraspinatus muscles, MRI remains the reference standard. MRI should not be used as a diagnostic screening tool in patients with chronic shoulder pain because it does not appear to significantly affect treatment or outcome.

Rim-Rent Tear of the Rotator Cuff: A Common and Easily Overlooked Partial Tear

OBJECTIVE

The purpose of this study was to determine the incidence of rim-rent rotator cuff tears in a population of patients referred for shoulder MRI and to determine the sensitivity of MRI for the detection of these tears.

CONCLUSION

Rim-rent tears are a common type of partial-thickness rotator cuff tear, much more commonly present than has been previously reported. In particular, infraspinatus rim-rent tears are more common than previously believed. Rim-rent tears of the infraspinatus tendon and those involving the anterior-most fibers of the supraspinatus tendon are commonly overlooked on MRI, possibly because of failure to appreciate the high incidence of these types of tears and failure to inspect the anterior-most fibers of the rotator cuff.

Magnetic Resonance Imaging of the Long Head of the Biceps Tendon

PURPOSE

To evaluate coplanar imaging of the long head of the biceps tendon.

METHODS

We retrospectively compared coronal oblique magnetic resonance images aligned with the principal supraspinatus tendon and with the intra-articular biceps tendon in 21 patients. Magnetic resonance images were analyzed for lesions depicted, including superior labral anteroposterior (SLAP) tears. Arthroscopic findings were reviewed.

RESULTS

Coronal oblique images aligned with intra-articular biceps tendon depicted 18 (86%) of 21 coplanar intra-articular biceps tendons. Coplanar images identified 6 cases of tendinosis, 1 tear, 3 intra-articular ruptures, and 20 (95.2%) of 21 exact origins of the tendon. Arthroscopy revealed 18 SLAP tears. The detection of SLAP lesions between both coronal oblique magnetic resonance images was significantly different (P = 0.007).

CONCLUSION

Advantages included imaging of the intra-articular biceps tendon with least partial-volume effects, definition of SLAP lesions and the tendinous origin at the supraglenoid tubercle, depiction of intra-articular bicipital ruptures, and increased sensitivity and specificity for intra-articular lesions.

Reliability of MRI assessment of supraspinatus tendinopathy

OBJECTIVE

To determine the interobserver and intraobserver reliability of the interpretation of MRIs for supraspinatus tendinosis.

METHODS

In the interobserver trial, the MRIs of 52 athletes' shoulders were observed by 3 observers on one occasion within a 2-month period. All 52 images were read by the most experienced musculoskeletal radiologist on 3 different occasions on separate days without access to the previous readings for the intraobserver trial. Supraspinatus tendinosis was graded using a modified 4-point scale from grades 0 to grade 3.

RESULTS

The grading of MRI-determined supraspinatus tendinosis was reliable, having an intraclass correlation (ICC) of 0.85 when assessed by the single well-trained observer. Interobserver reliability was only fair to good (ICC = 0.55).

CONCLUSIONS

Supraspinatus tendinosis can be accurately identified on MRI with little variation by a single well-trained observer. Interobserver reliability was only fair to good. Our data indicated that the reliability of the assessment was much greater in more experienced radiologists than in those with less experience.

MR imaging of the rotator cuff

MR imaging is the optimal method for evaluating suspected rotator cuff pathology. Current techniques of fast spin-echo imaging without and with fat suppression allow accurate identification and characterization of tendinous and myotendinous abnormalities of the rotator cuff. Impingement disorders, tendon degeneration, instability,and trauma comprise the multifactorial nature of rotator cuff disease. This article addresses the role of MR imaging in evaluating the rotator cuff and the importance of MR imaging in identifying other lesions that may mimic rotator cuff pathology. A rationale for protocol design, including MR arthrography and the use of specialized positioning, such as abduction and external rotation (ABER), are discussed.

Abnormalities on MRI of the subscapularis tendon in the presence of a full-thickness supraspinatus tendon tear

OBJECTIVE

Our objective was to determine the association between size and chronicity of full-thickness supraspinatus tendon tears with subscapularis tendon abnormalities on MRI.

MATERIALS AND METHODS

One hundred forty-two MRI examinations with full-thickness supraspinatus tendon tears were categorized on the basis of the supraspinatus muscle (SS): normal muscle (SS(normal)), suggesting a recent or small tear; reduced muscle bulk without fatty atrophy (SS(volume loss)); and those with fatty atrophy, suggesting a large or chronic tear (SS(fatty atrophy)). Subscapularis tendon abnormalities, the subcoracoid interval, and subcortical bone marrow edema in the lesser tuberosity and coracoid process were recorded.

RESULTS

The mean size of supraspinatus tendon tears in the SS(normal) (n = 45) group was 8.5 mm, 16.6 mm in SS(volume loss) (n = 53), and 29 mm in the SS(fatty atrophy) group (n = 44). Subscapularis tendon abnormality was identified in 22% of SS(normal) patients, 61% of SS(volume loss), and 86% of the SS(fatty atrophy) group (p < 0.001). There was moderate correlation between chronicity of supraspinatus tendon tears and subscapularis tendon abnormality (r = 0.47; p < 0.0001), with no correlation between the subcoracoid interval and abnormalities of the subscapularis tendon. There was moderate correlation between chronicity of supraspinatus tendon tears and bone marrow changes in the lesser tuberosity (r = 0.44; p < 0.0001).

CONCLUSION

Subscapularis tendon abnormality is related to chronicity of supraspinatus tendon tears. Bone marrow edema in the lesser tuberosity with a subscapularis tendon abnormality suggests increased stress at the subscapularis tendon insertion with chronicity of full-thickness supraspinatus tendon tears. Lack of correlation with the subcoracoid interval indicates that anterior instability may be a more important contributing factor to subscapularis tendon abnormalities than static subcoracoid impingement in the setting of a full-thickness supraspinatus tendon tear.

Dead men and radiologists don't lie: a review of cadaveric and radiological studies of rotator cuff tear prevalence

INTRODUCTION

Rotator cuff tears are a common pathology, with a varied prevalence reported.

PATIENTS AND METHODS

A literature review was undertaken to determine the cadaveric and radiological (ultrasonography and magnetic resonance imaging [MRI]) prevalence of rotator cuff tear. The radiological studies were subdivided into symptomatic and asymptomatic subjects.

RESULTS

Cadaveric rotator cuff tears were found in 4629 shoulders of which only 2553 met the inclusion criteria. The prevalence of full-thickness tears was 11.75% and partial thickness 18.49% (total tears 30.24%). The total tear rate in ultrasound asymptomatic was 38.9% and ultrasound symptomatic 41.4%. The total rate in MRI asymptomatic was 26.2% whilst MRI symptomatic was 49.4%.

DISCUSSION

The unselected cadaveric population should contain both symptomatic and asymptomatic subjects. A prevalence of tears between the symptomatic and asymptomatic radiological groups would be expected. However, apart from the MRI asymptomatic group, the radiological prevalence of rotator cuff tears exceeds the cadaveric.

CONCLUSIONS

Rotator cuff tears are frequently asymptomatic. Tears demonstrated during radiological investigation of the shoulder may be asymptomatic. It is important to correlate radiological and clinical findings in the shoulder.

Use of preoperative magnetic resonance imaging to predict rotator cuff tear pattern and method of repair

PURPOSE

To determine the magnetic resonance imaging (MRI) criteria for predicting rotator cuff tear pattern and method of repair.

TYPE OF STUDY

Retrospective MRI/arthroscopy correlation.

METHODS

Sixty-six preoperative MRI scans were evaluated. The maximum medial to lateral length (L) of the tear was measured on T2-weighted coronal cuts. The maximum anterior to posterior width (W) was measured on T2-weighted sagittal cuts. The cases were divided into 3 groups: group 1, short-wide tears, L < or = W, L < 2 cm; group 2, long-narrow tears, L > W, W < 2 cm; and group 3, long-wide tears, L > or = 2 cm, W > or = 2 cm.

RESULTS

Of the 66 MRI scans, 55 were adequate for standardized measurement. Group 1, 16 cases: 15 were found at arthroscopy to be crescent-shaped tears repaired end-to-bone; 1 was repaired with interval slides. Group 2, 22 cases: all 22 were repaired side-to-side/margin convergence. Group 3, 17 cases: 12 required interval slides, 1 partial repair was performed, and 4 were repaired side-to-side/margin convergence.

CONCLUSIONS

Tear pattern and method of repair can be predicted on high-quality MRI scan. Group 1, L < or = W and L < 2 cm, predicts a crescent-shaped tear and end-to-bone repair (positive predictive value, 93.8%). Group 2, L > W and W < 2 cm, predicts a longitudinal tear and side-to-side/margin convergence repair (positive predictive value 100%). Group 3, L > or = 2 cm and W > or = 2 cm, predicts a massive contracted tear and that primary end-to-bone or side-to-side repairs are usually not possible and that interval slides or partial repair may be necessary (positive predictive value, 76.5%). The overall diagnostic model based on usable MRI scans significantly predicted arthroscopic findings (P < .001 for chi-square test).

LEVEL OF EVIDENCE

Level III, development of diagnostic criteria with universally applied reference (nonconsecutive patients).

Evaluation of rotator cuff tears with magnetic resonance arthrography

The size and morphologic features of rotator cuff tears may influence treatment selection and affect final outcomes. Magnetic resonance arthrography allows observation of these features and other intraarticular structures. To assess the utility of magnetic resonance imaging in assessing size and morphologic features, we retrospectively reviewed observations on 41 shoulders in 37 consecutive surgically treated patients (mean age, 63.2 years) who had magnetic resonance imaging followed by magnetic resonance arthrography. The maximum rotator cuff defect size in the anteroposterior direction defined transverse size, and the maximum rotator cuff defect size in the mediolateral direction defined longitudinal size. Sensitivities for detecting full-thickness rotator cuff tears by magnetic resonance imaging and magnetic resonance arthrography were 90.2% and 100%, respectively. Maximum longitudinal and transverse dimensions of the tear as shown by magnetic resonance arthrography correlated better with intraoperative measurements (r2 = 0.85 transversely, 0.92 longitudinally) than magnetic resonance imaging measurements (r2 = 0.47 transversely, 0.26 longitudinally). The reproducibility of the two methods is similar. Magnetic resonance arthrography also allowed morphologic classification of the torn tendon as blunt end, tapering end, indistinct end, horizontal tear, and global tear. There was good agreement in classifying torn edges; the imaging findings agreed with findings at surgery. Magnetic resonance arthrography was more accurate in evaluating rotator cuff tear size and morphologic features than conventional magnetic resonance imaging.

Partial-thickness rotator cuff tears

Partial-thickness tears of the rotator cuff have been diagnosed with increased frequency because of a heightened awareness of the condition by clinicians and improved diagnostic methods. Research into the causes, natural history, and optimal treatment of this condition lags behind that of full-thickness tears. However, despite the limitations in the existing literature, there has emerged a consensus among shoulder experts that partial-thickness rotator cuff tears should be aggressively treated in the active athlete because of the unfavorable natural history of these lesions and success of accepted surgical algorithms. This review will provide an overview of the theories regarding the origins of partial-thickness rotator cuff tears, discuss the relative accuracy of accepted diagnostic techniques, and summarize the indications and methods of operative repair with an emphasis on the results of various treatment approaches.

Accuracy of CT arthrography in the assessment of tears of the rotator cuff

CT arthrography and arthroscopy were used to assess tears of the rotator cuff in 259 shoulders. Tear size was determined in the frontal and sagittal planes according to the classification of the French Arthroscopy Society.

CT arthrography had a sensitivity of 99% and a specificity of 100% for the diagnosis of tears of supraspinatus. For infraspinatus these figures were 97.44% and 99.52%, respectively and, for subscapularis, 64.71% and 98.17%. For lesions of the long head of the biceps, the sensitivity was 45.76% and the specificity was 99.57%.

Our study showed an excellent correlation between CT arthrography and arthroscopy when assessing the extent of a rotator cuff tear. CT arthrography should, therefore, be an indispensable part of pre-operative assessment. It allows determination of whether a tear is reparable (retraction of the tendon and fatty degeneration of the corresponding muscle) and whether this is possible by arthroscopy (degree of tendon retraction and extension to subscapularis).

Rotator cuff injuries and treatment

Rotator cuff problems are among the most commonly encountered disorders of the shoulder, and are commonly seen by primary care physicians. Their exact mechanism for susceptibility to injury remains unclear; however, with an understanding of the shoulder's anatomy and biomechanics, we are better able to treat the insults incurred on the cuff. Early recognition, proper treatment, and appropriate follow-up may expedite healing and prevent the occurrence of further injury or complications.

[Impingement syndrome of the shoulder]

The impingement syndrome is a clinical entity characterized by shoulder pain due to primary or secondary mechanical irritation of the rotator cuff. The primary factors for the development of impingement are a curved or hook-shaped anterior acromion as well as subacromial osteophytes, which may lead to tearing of the supraspinatus tendon. Secondary impingement is mainly caused by calcific tendinopathy, glenohumeral instability, os acromiale and degenerative changes of the acromioclavicular joint. Conventional radiographs are initially obtained, mainly for evaluation of the bony structures of the shoulder. If available, sonography can be used for detection of lesions and tears of the rotator cuff. Finally, MR-imaging provides detailed information about the relationship of the acromion and the acromioclavicular joint to the rotator cuff itself. In many cases however, no morphologic cause for impingement syndrome can be found. While patients are initially treated conservatively, chronic disease usually requires surgical intervention.

Prediction of primary reparability of massive tears of the rotator cuff on preoperative magnetic resonance imaging

We studied magnetic resonance images of rotator cuff tears to determine whether it was possible to establish preoperatively the feasibility or infeasibility of primary repair. The study comprised 27 shoulders in 26 patients who underwent magnetic resonance imaging before surgery because of complete tears of the rotator cuff and who were treated with primary repair or by the patch graft technique because primary repair was not feasible. The length and width of each tear, the thickness of the supraspinatus muscle at the superior margin of the glenoid, and the presence or absence of a high signal intensity in the infraspinatus muscle were statistically analyzed. Primary repair was often not feasible when both the length and width of the tear exceeded 40 mm on a preoperative magnetic resonance image, when the supraspinatus muscle was thin at the superior margin of the glenoid, and when a high signal intensity was observed in the infraspinatus muscle.