Rotator Cuff Tears

The spectrum of rotator cuff pathology ranges from tendinopathy and fraying to partial- or full-thickness tearing. Partial-thickness tears may be classified further as occurring on the articular or bursal surface of the tendon. A third type of partial-thickness tear is the intrasubstance tear, which occurs within the substance of the tendon without extending to the tendon surface. This type of tear is uncommon but is important to identify on MRI because the tendon surface may appear normal at arthroscopy and the tear may be missed.

Tendinopathy is identified by increased signal within the tendon substance. The abnormally increased signal intensity remains below that of fluid on T2-weighted sequences [7]. Tendinopathy may be present with or without tendon thickening or thinning. [1]. Fraying is described when the normal linear dark signal at the margin of a tendon becomes indistinct, but no gap in the tendon fibers is identified.

The most specific sign of a cuff tear is discontinuity of the cuff fibers with fluid signal in the intervening gap (Figs. 3 and 4). Unfortunately, this gap may only be seen in fairly large tears that measure more than several millimeters. For smaller tears the signal on T2-weighted imaging and secondary signs of cuff tearing should be considered carefully. Secondary signs include fluid in the subacromial or subdeltoid bursa, tendon retraction, and muscular atrophy. The latter two signs may have implications for the type of surgical repair that is required and so should be evaluated routinely on every MRI obtained for rotator cuff evaluation. The appearance of the torn fibers also should be noted, because poor quality, diffusely torn tendon may not be suitable for repair (Fig. 5).

The myotendinous junction normally is located beneath the AC joint. When it is more proximal a full-thickness tear should be suspected. In cases of partial-thickness tearing only the torn fibers retract. Some partial- and full-thickness

Partial Thickness Rotator Cuff Tear

Fig. 3. Full-thickness rotator cuff tear in 54-year-old patient. On fat-suppressed T2-weighted oblique coronal image (A), distal supraspinatus tendon (arrow) is disrupted by focal highsignal fluid and is mildly retracted from the greater tuberosity. More posterior slice (B) shows intact infraspinatus tendon (arrow) and normal attachment to the greater tuberosity. H, humeral head.

Fig. 3. Full-thickness rotator cuff tear in 54-year-old patient. On fat-suppressed T2-weighted oblique coronal image (A), distal supraspinatus tendon (arrow) is disrupted by focal highsignal fluid and is mildly retracted from the greater tuberosity. More posterior slice (B) shows intact infraspinatus tendon (arrow) and normal attachment to the greater tuberosity. H, humeral head.

cuff tears may have a delaminating component with the tear dissecting proxi-mally between the deep and superficial tendon fibers. The torn fibers may demonstrate different degrees of retraction (Fig. 6). The degree of retraction of the cuff fibers should be measured because this has a direct relationship to prognosis. The anterior-posterior dimension of the tear also is important and is measured best on the sagittal sequences.

An intrasubstance tear is described when there is fluid intensity signal within the substance of the tendon that does not extend to either the articular or bursal surface.

In some chronic cuff tears and following rotator cuff repair, granulation tissue and fibrosis may fill the gap, resulting in isointense or dark signal. In these

Rotator Cuff Tear

Fig. 4. Large partial-thickness bursal surface rotator cuff tear in 56-year-old patient. On T2-weighted oblique coronal image, distal supraspinatus tendon shows focal fluid (straight arrow) disrupting bursal fibers from greater tuberosity. Articular surface fibers (curved arroW) remain intact on greater tuberosity. H, humeral head.

Fig. 4. Large partial-thickness bursal surface rotator cuff tear in 56-year-old patient. On T2-weighted oblique coronal image, distal supraspinatus tendon shows focal fluid (straight arrow) disrupting bursal fibers from greater tuberosity. Articular surface fibers (curved arroW) remain intact on greater tuberosity. H, humeral head.

Subcoracoid Bursa Fluid Collection Mri

Fig. 5. Full-thickness rotator cuff tear and poor tendon quality in a 62-year-old patient. On fat-suppressed T2-weighted oblique coronal image, distal supraspinatus tendon (arrow) is moderately retracted from the greater tuberosity and shows increased signal intensity indicating severe degeneration. This tendon required extensive debridement at surgery. H, humeral head.

Fig. 5. Full-thickness rotator cuff tear and poor tendon quality in a 62-year-old patient. On fat-suppressed T2-weighted oblique coronal image, distal supraspinatus tendon (arrow) is moderately retracted from the greater tuberosity and shows increased signal intensity indicating severe degeneration. This tendon required extensive debridement at surgery. H, humeral head.

cases secondary signs of cuff tears again may be helpful. Occasionally MR ar-throgram is necessary to diagnose these chronic tears.

Although some small partial- and full-thickness tears also are not visible on conventional MRI, overall diagnostic accuracy is good with sensitivity and specificity of approximately 90% for full-thickness tears in high-field MRI systems. In cases in which there is a high suspicion for an occult small full-thickness or partial-thickness articular surface tear, MR arthrogram may aid in the diagnosis because it has higher reported sensitivity and specificity. In one recent study of 76 patients, MR arthrography was compared with results at arthroscopy [8]. The study found the sensitivity of MR arthrogram to be 84% and the specificity to be 96%. This minimally invasive procedure may

Mri Arthrogram Shoulder Impingement

Fig. 6. Large partial-thickness undersurface rotator cuff tear in 45-year-old patient Fat-suppressed T2-weighted oblique coronal image shows broad-based partial-thickness tear with prominent retraction of undersurface fibers (arrow) indicating tendon delamination and poor tendon quality. This large tear involved supraspinatus and infraspinatus tendons.

Fig. 6. Large partial-thickness undersurface rotator cuff tear in 45-year-old patient Fat-suppressed T2-weighted oblique coronal image shows broad-based partial-thickness tear with prominent retraction of undersurface fibers (arrow) indicating tendon delamination and poor tendon quality. This large tear involved supraspinatus and infraspinatus tendons.

be worthwhile in younger patients who have refractory shoulder pain, because studies have demonstrated that arthroscopic debridement of even shallow (25% thickness) articular surface tears can result in a significant decrease in pain [9]. In certain athletic populations with a high prevalence of cuff and labral tears it may be reasonable to proceed directly to MR arthrography without first obtaining a conventional MRI.

The main drawback of MR arthrography is patient discomfort following contrast injection. In the previously mentioned study [8] all 76 patients reported soreness above baseline symptoms for 24 to 48 hours after injection, although no serious complications, such as infection or nerve injury, occurred.

On MR arthrography a cuff tear is diagnosed when contrast leaks into the substance of the tendon (Figs. 7 and 8). A full-thickness tear is described when contrast from the glenohumeral joint leaks though the tendon into the subacromial or subdeltoid bursa. When contrast is seen in the subscapularis muscle some caution must be taken before diagnosis of a tear, because extra-articular injection of contrast during the fluoroscopic portion of the examination may occur. Bursal surface partial tears do not communicate with the joint space and thus are not seen better with arthrography compared with conventional MRI.

The supraspinatus is the most commonly torn tendon, often because of impingement by subacromial spurs or hypertrophic degenerative changes at the AC joint. The supraspinatus also may be torn in cases of internal impingement syndrome in which the posterior superior humeral head contacts the posterior glenoid during abduction with external rotation (Fig. 9).

The infraspinatus is the next most commonly torn tendon, often because of extension of tears from the supraspinatus. The subscapularis may become torn after massive rotator cuff tears of the supraspinatus and infraspinatus. It also may be torn in isolation after acute traumatic anterior shoulder dislocation t

Fig. 7. Partial-thickness undersurface rotator cuff tear in 42-year-old patient. Following intraarticular injection of contrast material, fat-suppressed T1-weighted oblique coronal image demonstrates focal high-signal contrast collection (arrow) at articular surface of supraspinatus. There is no contrast in the subacromial-subdeltoid space. H, humeral head.

Arthrogram Mri Rotator Cuff Torn

Fig. 8. Subtotal rotator cuff tear with severe tendon delamination in 49-year-old patient. On fat-suppressed Tl-weighted oblique coronal MR arthrographic image (A) contrast extends to the bursal surface fibers of supraspinatus tendon (arroW) without leak into the subacromial-subdeltoid space. H, humeral head. Fat-suppressed Tl-weighted abducted externally rotated (ABER) image (B) shows intact bursal surface fibers on the greater tuberosity (curved arroW) and retracted articular surface fibers (straight arrow). G, glenoid; H, humeral head. More posteriorly, ABER image (C) demonstrates contrast solution (arrow) within the infraspinatus tendon because of intrasubstance fiber delamination. G, glenoid; H, humerus.

Fig. 8. Subtotal rotator cuff tear with severe tendon delamination in 49-year-old patient. On fat-suppressed Tl-weighted oblique coronal MR arthrographic image (A) contrast extends to the bursal surface fibers of supraspinatus tendon (arroW) without leak into the subacromial-subdeltoid space. H, humeral head. Fat-suppressed Tl-weighted abducted externally rotated (ABER) image (B) shows intact bursal surface fibers on the greater tuberosity (curved arroW) and retracted articular surface fibers (straight arrow). G, glenoid; H, humeral head. More posteriorly, ABER image (C) demonstrates contrast solution (arrow) within the infraspinatus tendon because of intrasubstance fiber delamination. G, glenoid; H, humerus.

or less commonly because of subcoracoid impingement. Subcoracoid impingement in turn occurs in patients who have congenitally narrow coracohumeral intervals because of unusually long coracoid processes.

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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