Nirvikar Dahiya

Location and initiation of degenerative rotator cuff tears: An analysis of three hundred and sixty shoulders

BACKGROUND It has been theorized that degenerative rotator cuff tears most commonly involve the supraspinatus tendon, initiating at the anterior portion of the supraspinatus insertion and propagating posteriorly. The purposes of this study were to determine the most common location of degenerative rotator cuff tears and to examine tear location patterns associated with various tear sizes. METHODS Ultrasonograms of 360 shoulders with either a full-thickness rotator cuff tear (272) or a partial-thickness rotator cuff tear (eighty-eight) were obtained to measure the width and length of the tear and the distance from the biceps tendon to the anterior margin of the tear. Tears were grouped on the basis of their size (anteroposterior width) and extent (partial or full-thickness). Each tear was represented numerically as a column of consecutive numbers representing the tear width and distance posterior to the biceps tendon. All tears were pooled to graphically represent the width and location of the tears within groups. Frequency histograms of the pooled data were generated, and the mode was determined for each histogram representing various tear groups. RESULTS The mean age (and standard deviation) of the 233 subjects (360 shoulders) was 64.7 +/- 10.2 years. The mean width and length of the tears were 16.3 +/- 12.1 mm and 17.0 +/- 13.0 mm, respectively. The mean distance from the biceps tendon to the anterior tear margin was 7.8 +/- 5.7 mm (range, 0 to 26 mm). Histograms of the various tear groups invariably showed the location of 15 to 16 mm posterior to the biceps tendon to be the most commonly torn location within the posterior cuff tendons. The histograms of small tears (a width of <10 mm) and partial-thickness tears showed similar distributions of tear locations, indicating that the region approximately 15 mm posterior to the biceps tendon may be where rotator cuff tears most commonly initiate. CONCLUSIONS Degenerative rotator cuff tears most commonly involve a posterior location, near the junction of the supraspinatus and infraspinatus. The patterns of tear location across multiple tear sizes suggest that degenerative cuff tears may initiate in a region 13 to 17 mm posterior to the biceps tendon.

Relationship of Tear Size and Location to Fatty Degeneration of the Rotator Cuff

BACKGROUND Fatty degeneration of the rotator cuff muscles may have detrimental effects on both anatomical and functional outcomes following shoulder surgery. The purpose of this study was to investigate the relationship between tear geometry and muscle fatty degeneration in shoulders with a deficient rotator cuff. METHODS Ultrasonograms of both shoulders of 262 patients were reviewed to assess the type of rotator cuff tear and fatty degeneration in the supraspinatus and infraspinatus muscles. The 251 shoulders with a full-thickness tear underwent further evaluation for tear size and location. The relationship of tear size and location to fatty degeneration of the supraspinatus and infraspinatus muscles was investigated with use of statistical comparisons and regression models. RESULTS Fatty degeneration was found almost exclusively in shoulders with a full-thickness rotator cuff tear. Of the 251 shoulders with a full-thickness tear, eighty-seven (34.7%) had fatty degeneration in either the supraspinatus or infraspinatus, or both. Eighty-two (32.7%) of the 251 full-thickness tears had a distance of 0 mm between the biceps tendon and anterior margin of the tear. Ninety percent of the full-thickness tears with fatty degeneration in both muscles had a distance of 0 mm posterior from the biceps, whereas only 9% of those without fatty degeneration had a distance of 0 mm. Tears with fatty degeneration had significantly greater width and length than those without fatty degeneration (p < 0.0001). Tears with fatty degeneration had a significantly shorter distance posterior from the biceps than those without fatty degeneration (p < 0.0001). The distance posterior from the biceps was found to be the most important predictor for supraspinatus fatty degeneration, whereas tear width and length were found to be the most important predictors for infraspinatus fatty degeneration. CONCLUSIONS Fatty degeneration of the rotator cuff muscles is closely associated with tear size and location. The finding of this study suggests that the integrity of the anterior supraspinatus tendon is important to the development of fatty degeneration. Patients with full-thickness tears that extend through this area may benefit from earlier surgical intervention if fatty degeneration has not already occurred. Additionally, the findings suggest the importance of secure fixation and healing of the anterior aspect of the supraspinatus with surgical repair.

Clinical and radiographic outcomes of failed repairs of large or massive rotator cuff tears: minimum ten-year follow-up.

INTRODUCTION Little information exists regarding the long-term outcome after structural failure of rotator cuff repair. We previously reported clinical improvement, despite a 94% rate of failure of healing, at two years of follow-up in a cohort of eighteen patients who had undergone arthroscopic repair of massive rotator cuff tears. The purpose of the present study was to evaluate the ten-year results for these patients with known structural failures of rotator cuff repairs. METHODS Fifteen (83%) of eighteen patients were available for follow-up at ten years. Patients were evaluated with use of the American shoulder and elbow surgeons (ASES) score, the simple shoulder test (SST), a visual analog scale pain score, and the constant score. Radiographs and sonograms were assessed. RESULTS The average age was 74.6 years at the time of the latest follow-up. The average ASES score was 79.4 points (range, 50 to 95 points) and the average visual analog scale pain score was 2.2 points (range, 1 to 4 points); both scores were unchanged from those at two years. The average SST score was 9.2 points (range, 6 to 12 points), and the average age-adjusted Constant score was 73.2 points (range, 58.7 to 89.7 points). Of the patients with structurally failed repairs, all but one had radiographic signs of proximal humeral migration or cuff tear arthropathy: three had Hamada grade-2 changes, five had grade-3 changes, and three had Grade-4 changes (with two having grade-4a changes and one having grade-4b changes). Ultrasound confirmed the persistence of all tears that had been seen at two years. CONCLUSIONS Clinical improvements and pain relief after arthroscopic rotator cuff repair of large and massive tears are durable at the time of long-term (ten-year) follow-up, despite early structural failure of repair. Shoulders had a high rate of progression of radiographic signs associated with large rotator cuff tears. These results demonstrate that healing of large rotator cuff tears is not critical for long-term satisfactory clinical results in older patients.

Diagnostic performance and reliability of ultrasonography for fatty degeneration of the rotator cuff muscles

BACKGROUND Diagnostic evaluation of rotator cuff muscle quality is important to determine indications for potential operative repair. Ultrasonography has developed into an accepted and useful tool for evaluating rotator cuff tendon tears; however, its use for evaluating rotator muscle quality has not been well established. The purpose of this study was to investigate the diagnostic performance and observer reliability of ultrasonography in grading fatty degeneration of the posterior and superior rotator cuff muscles. METHODS The supraspinatus, infraspinatus, and teres minor muscles were prospectively evaluated with magnetic resonance imaging (MRI) and ultrasonography in eighty patients with shoulder pain. The degree of fatty degeneration on MRI was graded by four independent raters on the basis of the modified Goutallier grading system. Ultrasonographic evaluation of fatty degeneration was performed by one of three radiologists with use of a three-point scale. The two scoring systems were compared to determine the diagnostic performance of ultrasonography. The interobserver and intraobserver reliability of MRI grading by the four raters were determined. The interobserver reliability of ultrasonography among the three radiologists was determined in a separate group of thirty study subjects. The weighted Cohen kappa, percentage agreement, sensitivity, and specificity were calculated. RESULTS The accuracy of ultrasonography for the detection of fatty degeneration, as assessed on the basis of the percentage agreement with MRI, was 92.5% for the supraspinatus and infraspinatus muscles and 87.5% for the teres minor. The sensitivity was 84.6% for the supraspinatus, 95.6% for the infraspinatus, and 87.5% for the teres minor. The specificity was 96.3% for the supraspinatus, 91.2% for the infraspinatus, and 87.5% for the teres minor. The agreement between MRI and ultrasonography was substantial for the supraspinatus and infraspinatus (kappa = 0.78 and 0.71, respectively) and moderate for the teres minor (kappa = 0.47). The interobserver reliability for MRI was substantial for the supraspinatus and infraspinatus (kappa = 0.76 and 0.77, respectively) and moderate for the teres minor (kappa = 0.59). For ultrasonography, the interobserver reliability was substantial for all three muscles (kappa = 0.71 for the supraspinatus, 0.65 for the infraspinatus, and 0.72 for the teres minor). CONCLUSIONS The diagnostic performance of ultrasonography in identifying and grading fatty degeneration of the rotator cuff muscles was comparable with that of MRI. Ultrasonography can be used as the primary diagnostic imaging modality for fatty changes in rotator cuff muscles.

Ganglia of the Hand and Wrist: A Sonographic Analysis

OBJECTIVE The purpose of this study was to analyze the sonographic appearance of a large series of pathologically proven ganglia. MATERIALS AND METHODS A computer search of sonography and pathology reports for hand and wrist ganglia was performed. All sonography reports and images were reviewed for ganglion size, location, presence of a neck, echogenicity, acoustic enhancement, locules, color Doppler flow, margins, wall thickness, and calcifications and to determine if the ganglion was palpable or collapsed. All pathology reports were reviewed for histologic features that were then correlated with the sonographic images. Ganglia were categorized into three groups: simple, complex cystic, and solid-appearing. RESULTS Of 60 ganglia, 34 were complex, 91% of which were located within the dorsal or volar wrist; 97% had well-defined margins; 76%, locules; 68%, acoustic enhancement; 47%, a thick wall; 15%, internal reflectors; and 12%, blood flow. Of the 23 simple ganglia, 11 involved the extensor or flexor tendon sheath, 73% of which were simple. Complex ganglia had a larger mean volume than simple. Three ganglia were solid-appearing. A visible neck was seen in 25% of ganglia. CONCLUSION Most ganglia are complex rather than simple on sonography. Complex ganglia are larger than simple ganglia; located within the dorsal or volar wrist; and usually have well-defined margins, thick walls, locules, and acoustic enhancement. A small percentage have blood flow and internal reflectors. Simple ganglia are smaller and can occur within the volar or dorsal wrist, or flexor tendon sheath. Most flexor tendon sheath ganglia are simple rather than complex. Solid-appearing ganglia, although unusual, may mimic a benign neoplasm or synovitis.

Polypoid lesions of the gallbladder: Disease spectrum with pathologic correlation

Gallbladder polyps are seen on as many as 7% of gallbladder ultrasonographic images. The differential diagnosis for a polypoid gallbladder mass is wide and includes pseudotumors, as well as benign and malignant tumors. Tumefactive sludge may be mistaken for a gallbladder polyp. Pseudotumors include cholesterol polyps, adenomyomatosis, and inflammatory polyps, and they occur in that order of frequency. The most common benign and malignant tumors are adenomas and primary adenocarcinoma, respectively. Polyp size, shape, and other ancillary imaging findings, such as a wide base, wall thickening, and coexistent gallstones, are pertinent items to report when gallbladder polyps are discovered. These findings, as well as patient age and risk factors for gallbladder cancer, guide clinical decision making. Symptomatic polyps without other cause for symptoms, an age over 50 years, and the presence of gallstones are generally considered indications for cholecystectomy. Incidentally noted pedunculated polyps smaller than 5 mm generally do not require follow-up. Polyps that are 6-10 mm require follow-up, although neither the frequency nor the length of follow-up has been established. Polyps that are larger than 10 mm are typically excised, although lower size thresholds for cholecystectomy may be considered for patients with increased risk for gallbladder carcinoma, such as patients with primary sclerosing cholangitis.

Acute Cholecystitis: Do Sonographic Findings and WBC Count Predict Gangrenous Changes?

OBJECTIVE The purpose of our study was to determine, first, if gallbladder wall striations in patients with sonographic findings suspicious for acute cholecystitis are associated with gangrenous changes and certain histologic features; and, second, if WBC count or other sonographic findings are associated with gangrenous cholecystitis. MATERIALS AND METHODS Sixty-eight patients who underwent cholecystectomies within 48 hours of sonography comprised the study group. Sonograms and reports were reviewed for wall thickness, striations, Murphy sign, pericholecystic fluid, wall irregularity, intraluminal membranes, and luminal short-axis diameter. Medical records were reviewed for WBC count and pathology reports for the diagnosis. Histologic specimens were reviewed for pathologic changes. Statistical analyses tested for associations between nongangrenous and gangrenous cholecystitis and sonographic findings and for associations between wall striations and histologic features. RESULTS Ten patients had gangrenous cholecystitis and 57, nongangrenous cholecystitis. One had cholesterolosis. Thirty patients had wall striations: 60% had gangrenous and 42% nongangrenous cholecystitis. There was no association with the pathology diagnosis (p = 0.32). There was no association between any histologic feature and wall striations (p ≥ 0.19). A Murphy sign was reported in 70% of patients with gangrenous cholecystitis and in 82% with nongangrenous cholecystitis; there was no association with the pathology diagnosis (p = 0.39). Wall thickness and WBC count were greater in patients with gangrenous cholecystitis than in those with nongangrenous cholecystitis (p ≤ 0.04). CONCLUSION Gallbladder wall thickening and increased WBC counts were associated with gangrenous cholecystitis; however, there was considerable overlap between the two groups. Wall striations and a negative Murphy sign were not associated with gangrenous cholecystitis.

Ultrasound-guided chest biopsies.

Pulmonary nodules that are surrounded by aerated lung cannot be visualized with sonography. Therefore, percutaneous biopsy must be guided with computed tomography or fluoroscopy. Although this restriction only applies to central lung nodules, it has permeated referral patterns for other thoracic lesions and has retarded the growth of ultrasound-guided interventions. Nevertheless, sonography is an extremely flexible modality that can expeditiously guide many biopsy procedures in the thorax. Peripheral pulmonary nodules can be successfully biopsied with success rates exceeding 90% and complications rates of less than 5%. Orienting the probe parallel to the intercostal space facilitates biopsies of peripheral pulmonary nodules. Anterior mediastinal masses that extend to the parasternal region are often easily approachable provided the internal mammary vessels, costal cartilage, and deep great vessels are identified and avoided. Superior mediastinal masses can be sampled from a suprasternal or supraclavicular approach. Phased array probes or tightly curved arrays may provide improved access for biopsies in this location. Posterior mediastinal masses are more difficult to biopsy with ultrasound guidance because of the overlying paraspinal muscles. However, when posterior mediastinal masses extend into the posterior medial pleural region, they can be biopsied with ultrasound guidance. Because many lung cancers metastasize to the supraclavicular nodes, it is important to evaluate the supraclavicular region when determining the best approach to obtain a tissue diagnosis. When abnormal supraclavicular nodes are present, they often are the easiest and safest lesions to biopsy.

Doppler sonography of portal hypertension.

Doppler sonography is frequently obtained in patients with chronic liver disease, patients with suspected portal hypertension, and patients with known portal hypertension. In this clinical setting, it is important to understand both the normal hemodynamics of the liver and the morphological and hemodynamic changes that occur with portal hypertension. Among the many findings of portal hypertension are enlargement of the portal vein, decreased portal vein velocity, increased congestion index, development of portosystemic collaterals, and reversal of portal vein flow. The most important portal systemic collaterals to focus on with Doppler are the coronary vein and the umbilical vein. Using all of these clues, it is possible to diagnose portal hypertension with a high degree of sensitivity and specificity in most patients.

High-Resolution Sonography of the Normal Extrapelvic Vas Deferens

Objective. The purpose of this study was to determine the reliability of sonographic visualization of the normal extrapelvic vas deferens and to analyze its appearance and dimensions. Methods. Scans of the scrotum and spermatic cords were obtained in 25 fertile volunteers. Identification of the vas deferens was attempted bilaterally in the scrotal, suprascrotal, and prepubic segments in all volunteers. When possible, the total thickness and the diameter of the lumen were measured. Visualization and dimensions were correlated with the body mass index (BMI) and abstinence interval. Results. All segments of the vas deferens were identified bilaterally in all volunteers. In all cases, it appeared as an anechoic or very hypoechoic tubular structure that was noncompressible and contained no detectable blood flow. It was convoluted inferiorly and became straight as it progressed from the scrotum to the suprascrotal and prepubic segments. The lumen was seen in the suprascrotal segment in all of the volunteers except the one with the highest BMI. The total thickness of the vas ranged from 1.5 to 2.7 mm (mean, 1.89 mm). The lumen of the vas ranged from 0.2 to 0.7 mm (mean, 0.43 mm). There was no correlation between the luminal diameter and the abstinence interval. Conclusions. The extrapelvic portion of the vas deferens is reliably visualized sonographically. Its appearance is characteristic and reproducible. The lumen can be measured in almost all cases.