Severe atrophy and fatty degeneration of the infraspinatus muscle due to isolated infraspinatus tendon tear

Atrophy of both the supraspinatus and infraspinatus muscles is usually caused by chronic rotator cuff tear, but may also derive from suprascapular nerve entrapment at the spinoglenoid notch. Isolated infraspinatus muscle atrophy is uncommon, and typically associates with suprascapular nerve entrapment occurring distal to the spinoglenoid notch. However, isolated atrophy of the infraspinatus muscle due to insertional tear of the infraspinatus tendon may also occur. We present a case of a 43-year-old male with isolated infraspinatus muscle atrophy and fatty degeneration following an isolated full-thickness infraspinatus tendon tear at the insertion site on the humerus. While it is important to rule out other causes of infraspinatus muscle atrophy, such as concomitant rotator cuff tendon/muscle pathology or suprascapular nerve palsy, we present this case to increase awareness of this uncommon clinical presentation and the potential implications for treatment.     

MR assessment of the repaired rotator cuff: prevalence, size, location, and clinical relevance of tendon rerupture

The objectives of this study were to use magnetic resonance (MR) imaging to evaluate the prevalence, size, location, and clinical relevance of tendon rerupture following complete repair of full-thickness rotator cuff tear (RCT). A total of 78 surgically proven full-thickness rotator cuff tears in 74 patients were retrospectively included in the study. Clinical assessment was performed using the University of California at Los Angeles score. Postoperative MR imaging was evaluated to determine prevalence, size, and location of tendon rerupture. At a mean 48.4 months’ follow-up, 62 shoulders (79.5%) had favorable outcomes and 45 shoulders (57.6%) showed rerupture on MR imaging studies. Reruptures were significantly more prevalent among patients with intermediate-to-bad outcomes (81.3%), with surgically demonstrated two-tendon tears (78.9%) or three-tendon tears (100%), and with preoperative fatty degeneration of the supraspinatus muscle greater than 1 (91.6%). Reruptures were also significantly larger in those subgroups. Complete repair of RCT of all sizes may have favorable outcomes in a significant proportion of patients in spite of a high prevalence of reruptures. Preoperative tear size and degree of muscle fatty degeneration influence the prevalence and rerupture size. After repair of supraspinatus tears, reruptures tend to invade the posterior aspect of the tendon.     

磁共振化学位移成像定量测量肩袖损伤后冈上肌脂肪性退变

目的：探讨MR化学位移成像技术在定量测量肩袖损伤后冈上肌脂肪性退变中的临床应用价值。方法：38例临床上疑有肩袖损伤或肩峰撞击的患者为研究对象,行MR间接关节造影后,进行常规序列和化学位移序列MRI扫描。根据MR间接关节造影检查结果,肩袖损伤后冈上肌肌腱病理改变可分为4组：正常组、肌腱炎组、部分撕裂组和完全撕裂组。通过测定冈上肌的信号强度,然后分别计算出信号强度抑制率和信号指数值作为反映脂肪变性程度的指标,对比分析正常组和肩袖损伤各组的冈上肌脂肪变性程度。统计学方法采用Wilcoxon秩和检验。结果：正常组、肌腱炎组、部分撕裂组和完全撕裂组冈上肌信号强度抑制率中位数分别是-5．51％（-7．85％～3．50％）、-14．78％（-29．31％～-5．63％）、-31．74％（-45．54％～-13．63％）和-44．50％（-57．32％～-26．27％）,信号强度指数中位数依次为3．91％（-4．37％～13．83％）、12．75％（5．73％～27．38％）、25．17％（14．32％～34．13％）和38．26％（27．66％～53．94％）。正常组与部分撕裂组、正常组与完全撕裂组、肌腱炎组与完全撕裂组间两两比较,差异有高度统计学意义（P〈0．01）;正常组与肌腱炎组、肌腱炎组与部分撕裂组、部分撕裂组与完全撕裂组间两两比较,差异有统计学意义（P〈0．05）。结论：MR化学位移成像技术是定量测定冈上肌脂肪性退变程度的-种有I临床应用价值的手段,有助于对肌腱病变进行分级并指导临床治疗。     

Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

Purpose To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Materials and methods Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. Results There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Conclusion Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear.     

The rotator cuff functional index

BACKGROUND: Despite improvements in the clinical assessment of rotator cuff injuries, shortcomings exist in diagnosing rotator cuff tears. PURPOSE: To formulate a clinical rotator cuff functional index for predicting rotator cuff tears based on handheld dynamometer measurements for shoulder strength testing and to assess its ability to diagnose a rotator cuff tear. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Preoperative handheld dynamometer measurements, including supraspinatus, external rotation, internal rotation, adduction, and lift-off force, were compared in 100 patients with full-thickness rotator cuff tears (> 1.0 cm) and 100 patients with no rotator cuff injury (confirmed by arthroscopy). Using multiple logistic regression analysis, the rotator cuff functional index and index for rotator cuff tear size were formulated in which 100 represented excellent rotator cuff function and less than 0 indicated a full-thickness supraspinatus tear. Each patient's index was calculated to determine its clinical value in predicting a rotator cuff tear; the Pearson correlation coefficient was established for the rotator cuff functional index for rotator cuff size. RESULTS: Two handheld dynamometer measurements predicted a rotator cuff tear (P < .001, r = 0.53), with rotator cuff functional index = 1.27 * supraspinatus (N) - 0.72 * adduction (N) - 11.6, but not tear size (r = 0.38). In predicting a rotator cuff tear (rotator cuff functional index < 0 = rotator cuff tear; rotator cuff functional index > 0 = no tear), the rotator cuff functional index had 83% sensitivity, 79% specificity, 80% positive predictive value, 82% negative predictive value, likelihood ratio of 4.0 for a positive test result and 0.2 for a negative test result and an accuracy of 81%. CONCLUSION: The 2 most useful tests for determining a rotator cuff tear with a handheld dynamometer were supraspinatus force and adduction force (as negative control). A functional index based on these measurements was able to rule out a rotator cuff tear and predict the presence but not the size of the tear.     

MR evaluation of subscapularis tears.

PURPOSE: The purpose of this work was to describe the MR appearance of tears of the subscapularis tendon and compare the usefulness of different imaging planes as well as note the association of subscapularis tears with other rotator cuff tears and biceps tendon dislocations. METHOD: MR studies at 1.5 T over an 8 year interval were retrospectively assessed for the presence of a rotator cuff tear and/or tear of the subscapularis tendon. Images that showed a subscapularis tear were reviewed for the presence of a visible tear separately on the axial, coronal, and sagittal images. The MR studies were also evaluated for associated tears of the supraspinatus, infraspinatus, and teres minor muscles as well as biceps tendon dislocation and the "naked humerus sign" on coronal images. Last, clinical records and surgical reports were reviewed. RESULTS: Forty-five (2%) of 2,167 rotator cuff tears involved the subscapularis; 27% were partial and 73% were complete tears. Tears were best seen in the sagittal oblique plane. Almost all subscapularis tears were an extension of typical rotator cuff tears: supraspinatus in 35 patients (79%), extending into infraspinatus tears in 25 (56%) and into teres minor tears in 2 patients (4%). Bicipital dislocations were seen in 22 patients (49%), and three complete tears of the biceps (7%) were noted as well. The naked humerus sign was demonstrated in 31 patients (69%). Surgical reports that confirmed the MR findings were available for 15 patients. CONCLUSION: About 2% of rotator cuff tears involve the subscapularis tendon. Most subscapularis tears are extensions of supraspinatus tears and frequently involve the biceps tendon.     

2D SPLASH: a new method to determine the fatty infiltration of the rotator cuff muscles

The objective of this paper is to quantify the fatty degeneration (infiltration) of rotator cuff muscles with a new spectroscopic FLASH (SPLASH) sequence. Before planned surgery (reconstruction or muscle transfer), 20 patients (13 men, 7 women; 35–75 years) with different stages of rotator cuff disease underwent an MR examination in a 1.5-T unit. The protocol consists of imaging sequences and a newly implemented SPLASH, which allows an exact quantification of the fat/water ratio with a high spatial resolution in an arbitrarily shaped region of interest (ROI). The percentages of fat in the rotator cuff muscles were determined. To determine statistically significant differences between the different stages of rotator cuff tear, a Kruskal-Wallis H test was used. Fatty infiltration of the supraspinatus muscle was correlated with cross-sectional area (CSA) measures (Bravais-Pearson). We found significant differences between different stages of rotator cuff disease, the fatty infiltration and the volume loss (determined by the occupation ratio) of the supraspinatus muscle. With the increasing extent of rotator cuff disease, fatty infiltration increases significantly, as does the volume loss of the supraspinatus muscle. Comparing fatty infiltration and the occupation ratio individually, there was only a moderate inverse correlation between fatty infiltration and the occupation ratio, with considerable variation of data. Fatty infiltration of the infraspinatus muscle occurred when the infraspinatus tendon was involved to a lesser extent. The SPLASH sequence allows exact quantification of fatty infiltration in an arbitrarily shaped ROI. The extent of atrophy and fatty infiltration correlates with the size of the tear. Atrophy and fatty infiltration correlate only moderately and should be evaluated separately.     

Clinical Y-view versus 3-dimensional assessments of intramuscular fat in patients with full-thickness rotator cuff tears

Rationale and Objectives.Recent evidence suggests an inhomogeneous distribution of intramuscular rotator cuff fat infiltration (FI) in a small sample of individuals with rotator cuff tears, yet clinically just a few slices at the scapular Y-view are used to evaluate FI in patients with rotator cuff tears. The purpose of this study was to determine if assessment of FI using the scapular Y-view is representative of the entire muscle in patients with full-thickness rotator cuff tears, and whether this varies by tear size.Materials and methodsPatients (N = 25) diagnosed with full-thickness rotator cuff tear and confirmed with magnetic resonance imaging (MRI) were included. Fat-water sequences were used to objectively quantify mean FI (%) in the entire 3D muscle and the mean from 3 slices at the Y-view. Mixed-model 2 × 2 ANOVAs were used to assess for differences between methods, and if results vary by tear-size.ResultsThere were no statistically significant differences between mean amount of FI of the entire 3D muscle and mean Y-view in the supraspinatus or infraspinatus muscles (p > 0.05). Additionally, this did not differ across tear size groups (p > 0.05).ConclusionResults of this study suggest FI assessed in the Y-view is not different (mean difference < 1.0%) from FI of the entire 3D muscle in patients with full-thickness rotator cuff tears. Therefore, the clinical utility of evaluating rotator cuff intramuscular fat infiltration with the Y-view is further supported in patients with full-thickness rotator cuff tears across tear sizes.     

Fatty infiltration and atrophy of the rotator cuff do not improve after rotator cuff repair and correlate with poor functional outcome

BACKGROUND: The role of degenerative changes in rotator cuff musculature with respect to the functional outcomes of rotator cuff repair have only recently been recognized and are still not well understood. In addition, the reversibility of these changes with repair of the tendons is questionable. HYPOTHESIS: Poorer preoperative muscle quality negatively affects outcome, and a successful outcome (in terms of a healed repair) might demonstrate improvements in fatty infiltration and muscle atrophy. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Thirty-eight patients (mean age, 62 years) were prospectively evaluated with preoperative and 1-year postoperative clinical examination and appropriate magnetic resonance image sequencing to determine grades of muscle atrophy and fatty infiltration of the supraspinatus and infraspinatus muscles. American Shoulder and Elbow Society (ASES), Constant, and pain scores were determined as well as strength measurements. The retear rate and progression of muscle degeneration were also evaluated. Independent predictors of outcome measurements and cuff integrity were determined. RESULTS: The overall clinical outcome, including ASES, Constant, and pain scores, improved significantly (P < .0001). Strength in forward elevation improved significantly (P < .006), while external rotation strength did not. There was a strongly negative correlation between muscle quality and outcome results in most cases. When the results were adjusted for multivariate effect, muscle atrophy and fatty infiltration of the infraspinatus muscle were the only independent predictors of ASES and Constant scores (P < .03). Tear size and rotator cuff healing did not play an independent role. Tear size, however, was the only independent predictor of ultimate cuff integrity (P = .002). Both atrophy and fatty infiltration progressed significantly over the course of the study. In cases in which the tendon had re-torn, the progression was found to be more significant than when the repair proved successful (P < .003). CONCLUSION: Muscle atrophy and fatty infiltration of the rotator cuff muscles, particularly of the infraspinatus, play a significant role in determining functional outcome after cuff repair. Tear size appears to have the most influential effect on repair integrity. A successful repair did not lead to improvement or reversal of muscle degeneration and a failed repair resulted in significantly more progression. In general, healed repairs demonstrated minimal progression. These findings suggest that repairs should be performed, if possible, before more significant deterioration in the cuff musculature in order to optimize outcomes, and that understanding the degree of muscle atrophy and fatty infiltration before surgery can help guide patient expectations.     

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.     

巨大肩袖损伤的手术修复结果

目的 探讨关节镜治疗巨大肩袖损伤的临床效果及影响因素.方法自2007年9月至2009年6月接受手术治疗的巨大肩袖损伤患者16例,男6例,女10例;平均年龄61.5岁.采取关节镜下双排重建对损伤肩袖进行修复.记录术前及最终随访时的疼痛、活动范围、前屈上举的肌肉力量以及功能评分,进行配对t检验;并按不同年龄、病程进行分组,进行统计学分析.结果 所有患者均顺利愈合,术前疼痛视觉模拟评分(visual analogue score,VAS)为5.6,前屈上举为69.1°,外旋为14.7°,内旋达L1水平,Constant-Murley评分为39,加州大学洛杉矾分校评分(UCLA)为10.4,肩关节简单评分(SST)为2.8,前屈上举的肌力相当于健侧的10.7%.术后VAS为1.7,前屈上举为151.2°,外旋为32.2°,内旋达T10水平,Constant-Murley评分为85.6,UCLA为28,SST为8.8,前屈上举的肌力为健侧的65.0%.术后与术前在疼痛、活动范围、肌力及功能方面差异均有统计学意义(P<0.01).不同性别和不同病程在手术前后的差异均无统计学意义.结论通过关节镜手术对损伤的肩袖进行双排重建可获得较为满意的临床治疗结果.

Abstract：

Objective To evaluate the clinical results of arthroscopic repair of massive rotator cuff tear. Methods The study involved 16 patients with massive rotator cuff tears treated arthroscopically from September 2007 to June 2009. There were 6 males and 11 females at average age 61.5 years (45-75 years). The rotator cuff tears was repaired with arthroscopic double-row reconstruction. The range of motion, pain, strength of flexed elevation and function evaluation score were all recorded before operation and at final follow-up. The results were evaluated by t test and compared according to age and course of disease. Results All patients were healed without complications and the outcome was improved significantly ( P < 0.01 ). The mean VAS score was improved from preoperative 5.6 to postoperative 1.7,the average forward flexion from 69. 1°to 151.2°, the average external rotation from 14.7° to 32.2°, and internal rotation from L1 level to T10, the mean Constant-Murle from 39 to 85, the mean UCLA from 10.4 to 28, the mean SST from 2.8 to 8.8 and the strength of flexed elevation from 10.7% of normal side to 65.0%. Compared with preoperation, there was statistical difference in aspects of pain, range of motion, muscle strength and function in postoperation (P < 0.01 ). Conclusion Arthroscopic doublerow fixation can attain satisfactory results in repair of massive rotator cuff tear.     

Infraspinatus muscle atrophy: implications?

PURPOSE: To evaluate associated findings in patients who exhibited atrophy of infraspinatus muscle at magnetic resonance (MR) examination of their shoulders to clarify implications of this abnormality. MATERIALS AND METHODS: With an electronic database search, cases of advanced infraspinatus muscle atrophy in patients who underwent MR imaging during a 1-year period for evaluation of shoulder pain or dysfunction were identified. The analysis was restricted to cases interpreted by one reader who applied a standardized method of reporting. Associated MR imaging findings in these cases were tabulated. RESULTS: Advanced infraspinatus muscle atrophy was encountered in 51 (4.3%) of 1,191 MR examinations of the shoulder. Tears of the infraspinatus tendon were present in only 27 (53%) of 51 cases. In 46 (90%) of 51 cases, a full-thickness tear was present in the anterior portion of the rotator cuff. In 10 (20%) of 51 cases with infraspinatus muscle atrophy, cuff muscle atrophy was confined to the infraspinatus muscle. Cuff muscle atrophy was isolated to the infraspinatus muscle in four (17%) of 24 cases in which atrophy of the infraspinatus muscle was present despite an intact tendon. In none of the 51 cases was there a mass in the suprascapular or sphenoglenoid notch. CONCLUSION: Infraspinatus muscle atrophy typically occurs with tendon tears in the anterior aspect of the rotator cuff. Concomitant atrophy in the supraspinatus muscle often is present, but infraspinatus muscle atrophy can occur in isolation, and this finding does not imply that the infraspinatus tendon is ruptured.     

Evaluation of Rotator Cuff Tendon Tears: Comparison of Multidetector CT Arthrography and 1.5-T MR Arthrography

Purpose: To compare the diagnostic performance of multidetector computed tomographic (CT) arthrography and 1.5-T magnetic resonance (MR) arthrography in the evaluation of rotator cuff lesions, with arthroscopic correlation. Materials and Methods: This study was approved by the institutional ethical committee, and informed consent was obtained from all patients. CT and MR arthrographic images prospectively obtained in 56 consecutive patients, following the same arthrographic procedure, were independently evaluated by two radiologists. Arthroscopy, performed within 1 month of the imaging, was used as the reference standard. Sensitivity and specificity of CT and MR arthrography were compared by using the McNemar test. Interobserver and intertechnique agreement for detecting rotator cuff lesions were measured and compared with κ and Z statistics. The Bland-Altman method was used to determine interobserver and intertechnique agreement for measuring tendon tears. For grading fatty infiltration of rotator cuff muscles, κ and Z statistics were used. Results: There was no statistically significant difference in sensitivity and specificity between CT arthrography and MR arthrography in depiction of rotator cuff lesions. The respective sensitivity and specificity of CT arthrography were 92% and 93%-97% for the supraspinatus, 100% and 77%-79% for the infraspinatus, 75%-88% and 85%-90% for the subscapularis, and 55%-65% and 100% for the biceps tendon. The respective sensitivity and specificity of MR arthrography were 96% and 83%-93% for the supraspinatus, 88%-100% and 81%-83% for the infraspinatus, 75%-88% and 90%-100% for the subscapularis, and 65%-85% and 100% for the biceps tendon. Interobserver agreement was substantial to almost perfect (κ = 0.744-0.964 for CT arthrography; κ = 0.641-0.893 for MR arthrography), and intertechnique agreement was almost perfect (κ > 0.819). CT and MR arthrography both yielded moderate interobserver and intertechnique agreement for measuring rotator cuff tears and grading muscle fatty infiltration. Conclusion: Data suggest that CT and MR arthrography have similar diagnostic performance for the evaluation of rotator cuff tendon tears. ? RSNA, 2012.     

Association of biceps tendon tears with rotator cuff abnormalities: degree of correlation with tears of the anterior and superior portions of the rotator cuff

OBJECTIVE: This study was performed to examine the relationship and association of abnormalities seen in the long head of the biceps brachii tendon to abnormal findings in the rotator cuff. MATERIALS AND METHODS: One hundred eleven patients underwent MR imaging for shoulder pain followed by arthroscopic or open shoulder surgery from January 1997 to December 2000. Patients were identified by a retrospective search, and all consecutive patients having undergone both MR imaging and surgery were included in the patient cohort. Official MR imaging interpretations were compared with operative reports, and all findings were recorded. RESULTS: Twenty-three patients were identified with partial- or full-thickness tears of the long head of the biceps tendon. The sensitivity, specificity, and accuracy of unenhanced MR imaging of the shoulder for detecting these bicipital tears were 52%, 86%, and 79%, respectively. When a tear was present in the biceps tendon, the prevalence of supraspinatous, infraspinatus, and subscapularis tendon tears was 96.2%, 34.6%, and 47.1%, respectively. Patients with biceps tendon tears were significantly more likely to also have subscapularis tendon tears (p < 0.0001) and supraspinatous tendon tears (p < 0.008) than those patients who did not have biceps tendon tears. No significant relationship was found between the presence or absence of a biceps tendon tear and the presence or absence of a infraspinatus or teres minor tendon tear (p = 0.17). CONCLUSION: Tears of the long head of the biceps tendon have a statistically significant association with tears of the anterior and superior rotator cuff and are highly correlated with tears of the supraspinatous and subscapularis tendons. When tears of these tendons are detected, specific attention directed toward the long biceps tendon is warranted to characterize the status of this structure that provides additional stability to the shoulder joint.     

Repair of rotator cuff tears in tennis players.

Twenty-three tennis players with a symptomatic full-thickness rotator cuff tear underwent anterior acromioplasty and rotator cuff repair. There were 8 small tears (less than 1 cm), 5 moderate tears (1 to 3 cm), 2 large tears (3 to 5 cm), and 8 massive tears (greater than 5 cm). The dominant shoulder was involved in all patients and all were unable to play tennis before surgery. Eleven patients experienced a traumatic event that caused an injury, 6 while playing tennis, and 12 patients had a gradual onset of symptoms. At average follow-up of 42 months, 19 patients (83%) achieved a good result, were pain-free, and were able to play tennis at their presymptomatic competitive level. Three patients (13%), all with massive tears, had a satisfactory result and were able to play tennis, although at a lower competitive level secondary to weakness. One patient (4%), who also had a massive tear, had an unsatisfactory result and was unable to play tennis.     

Rotator cuff tears: assessment with MR arthrography in 275 patients with arthroscopic correlation

We assessed the diagnostic performance of magnetic resonance (MR) arthrography in the diagnosis of articular-sided partial-thickness and full-thickness rotator cuff tears in a large symptomatic population. MR arthrograms obtained in 275 patients including a study group of 139 patients with rotator cuff tears proved by arthroscopy and a control group of 136 patients with arthroscopically intact rotator cuff tendons were reviewed in random order. MR imaging was performed on a 1.0 T system (Magnetom Expert, Siemens). MR arthrograms were analyzed by two radiologists in consensus for articular-sided partial-thickness and full-thickness tears of the supraspinatus, infraspinatus, and subscapularis tendons. At arthroscopy, 197 rotator cuff tears were diagnosed, including 105 partial-thickness (93 supraspinatus, nine infraspinatus, three subscapularis) and 92 full-thickness (43 supraspinatus, 20 infraspinatus, 29 subscapularis) tendon tears. For full-thickness tears, sensitivity, specificity, and accuracy were 96%, 99%, and 98%, respectively, and for partial tears 80%, 97%, and 95%, respectively. False negative and positive assessments in the diagnosis of articular-sided partial-thickness tears were predominantly [78% (35/45)] observed with small articular-sided (Ellman grade1) tendon tears. MR arthrography is highly accurate in the diagnosis of full-thickness rotator cuff tears and is accurate in the diagnosis of articular-sided partial-thickness tears. Limitations in the diagnosis of partial-thickness tears are mainly restricted to small articular-sided tears (Ellman grade 1) due to difficulties in differentiation between fiber tearing, tendinitis, synovitic changes, and superficial fraying at tendon margins.     

Fatty degeneration of the rotator cuff muscles on pre- and postoperative CT arthrography (CTA): is the Goutallier grading system reliable?

Objectives

To retrospectively evaluate fatty degeneration (FD) of rotator cuff muscles on CTA using Goutallier’s grading system and quantitative measurements with comparison between pre- and postoperative states.

Materials and methods

IRB approval was obtained for this study. Two radiologists independently reviewed pre- and postoperative CTAs of 43 patients (24 males and 19 females, mean age, 58.1 years) with 46 shoulders confirmed as full-thickness tears with random distribution. FD of supraspinatus, infraspinatus/teres minor, and subscapularis was assessed using Goutallier’s system and by quantitative measurements of Hounsfield units (HUs) on sagittal images. Changes in FD grades and HUs were compared between pre- and postoperative CTAs and analyzed with respect to preoperative tear size and postoperative cuff integrity. The correlations between qualitative grades and quantitative measurements and their inter-observer reliabilities were also assessed.

Results

There was statistically significant correlation between FD grades and HU measurements of all muscles on pre- and postoperative CTA (p < 0.05). Inter-observer reliability of fatty degeneration grades were excellent to substantial on both pre- and postoperative CTA in supraspinatus (0.8685 and 0.8535) and subscapularis muscles (0.7777 and 0.7972), but fair in infraspinatus/teres minor muscles (0.5791 and 0.5740); however, quantitative Hounsfield units measurements showed excellent reliability for all muscles (ICC: 0.7950 and 0.9346 for SST, 0.7922 and 0.8492 for SSC, and 0.9254 and 0.9052 for IST/TM). No muscle showed improvement of fatty degeneration after surgical repair on qualitative and quantitative assessments; there was no difference in changes of fatty degeneration after surgical repair according to preoperative tear size and post-operative cuff integrity (p > 0.05). The average dose-length product (DLP, mGy · cm) was 365.2 mGy · cm (range, 323.8-417.2 mGy · cm) and estimated average effective dose was 5.1 mSv.

Conclusions

Goutallier grades correlated well with HUs of rotator cuff muscles. Reliability was excellent for both systems, except for FD grade of IST/TM muscles, which may be more reliably assessed using quantitative measurements.     

Rotator cuff tear: clinical experience with sonographic detection

Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury.     

Sonography of the postoperative rotator cuff

In experienced hands, high-resolution real-time sonography has been shown to be an accurate noninvasive method for diagnosis of rotator cuff tears. The sonographic appearance of the postoperative rotator cuff has not been previously reported. Forty postoperative patients were studied sonographically 1 week to 6 years after rotator cuff repair. The postoperative rotator cuff is abnormally echogenic and can be very similar in appearance to a small rotator cuff tear in a nonoperated patient. Soft-tissue planes about the tendon are distorted or absent. Criteria for diagnosis of retear must be different from those used in detecting new tears in a nonoperated cuff. Postoperative echogenicity is normal, but the finding of a defect or gap within the rotator cuff tendon is the only accurate sign of a recurrent rotator cuff tear.