合并肩袖损伤的肩关节盂唇损伤的临床特征

目的 分析合并肩袖损伤的肩关节盂唇损伤患者的临床特征,提出其发病规律与病变特点,为临床微创手术治疗提供参考. 方法 本组50例,其中男28例,女22例;年龄30～58岁,平均45岁.记录患者的损伤机制、损伤时间、临床症状、体征,摄X线片和MRI.根据临床诊断,采用肩关节镜微创手术修复盂唇和肩袖损伤,记录损伤部位、范围及程度并进行分析.本组表现前盂唇损伤37例,上盂唇撕裂8例,后盂唇损伤5例;肩袖损伤轻度36例,中度10例,重度3例,特大裂口1例.其中肩袖前侧(冈上肌前侧)损伤21例,中部损伤(冈上肌与冈下肌部)16例,后部损伤(冈下肌部、小圆肌)13例.盂唇损伤的MRI表现为:三角外形消失,前关节囊扩大.肩袖损伤表现为:损伤部位高信号,连续性丧失. 结果 本组患者平均随访36个月(6～72个月),临床效果满意.美国加州洛杉矶大学关节功能评分标准(UCLA)评分:术前(15±3)分,术后(32±3)分(P＜0.01). 结论 创伤性肩关节盂唇损伤患者常同时合并肩袖损伤,临床上应予重视,避免遗漏诊断或耽误治疗.盂唇损伤范围与肩袖损伤部位存在对应关系,盂唇损伤范围越大,肩袖损伤越接近后侧.     

SLAP lesions: anatomy, clinical presentation, MR imaging diagnosis and characterization

Superior labral anterior posterior (SLAP) tears are an abnormality of the superior labrum usually centered on the attachment of the long head of the biceps tendon. Tears are commonly caused by repetitive overhead motion or fall on an outstretched arm. SLAP lesions can lead to shoulder pain and instability. Clinical diagnosis is difficult thus imaging plays a key diagnostic role. The normal anatomic variability of the capsulolabral complex can make SLAP lesions a diagnostic challenge. Concurrent shoulder injuries are often present including rotator cuff tears, cystic changes or marrow edema in the humeral head, capsular laxity, Hill-Sachs or Bankart lesion. The relevant anatomy, capsulolabral anatomic variants, primary and secondary findings of SLAP tears including MR arthrography findings, types of SLAP lesions and a practical approach to labral lesions are reviewed.     

The resisted supination external rotation test: a new test for the diagnosis of superior labral anterior posterior lesions

PURPOSE: To evaluate a new clinical test, the resisted supination external rotation test, for the diagnosis of superior labral anterior posterior lesions of the shoulder. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Forty athletes (average age, 23.9 years) with activity-related shoulder pain were enrolled in the study. The patients underwent 3 different tests designed specifically to detect superior labral anterior posterior lesions (the resisted supination external rotation test, the crank test, and the active compression test); the tests were performed in a random order on the affected shoulder. The results of the tests were compared with arthroscopic findings. RESULTS: Out of 40 athletes, 29 (72.5%) had superior labral anterior posterior tears. The resisted supination external rotation test had the highest sensitivity (82.8%), specificity (81.8%), positive predictive value (92.3%), negative predictive value (64.3%), and diagnostic accuracy (82.5%) of all tests performed. CONCLUSION: By re-creating the peel-back mechanism, the resisted supination external rotation test is more accurate than 2 other commonly used physical examination tests designed to diagnose superior labral anterior posterior tears in overhead-throwing athletes. By using this test in the context of a thorough clinical history and physical examination, lesions of the superior labrum can be more reliably diagnosed.     

Evaluation of the rotator cuff and glenoid labrum using a 0.2-Tesla extremity magnetic resonance (MR) system: MR results compared to surgical findings.

The purpose of this investigation was to evaluate the diagnostic capabilities of magnetic resonance imaging (MRI) performed using a dedicated-extremity MR system in detecting lesions of the rotator cuff and glenoid labrum. This retrospective study compared the MR results obtained in 47 patients that underwent MRI using a 0.2-Tesla extremity MR system (E-scan) to the surgical findings. MR images of the shoulder were obtained as follows: shoulder coil, T1-weighted, coronal-oblique and axial images; short Tau inversion recovery (STIR), coronal-oblique images; and T2-weighted, coronal-oblique, sagittal-oblique, and axial images. The MR examinations were interpreted by three highly experienced, musculoskeletal radiologists. Open surgical (N = 26) or arthroscopic (N = 21) procedures were performed within a mean time of 33 days after MRI. The surgical findings revealed rotator cuff tears in 28 patients and labral lesions in 9 patients. For the rotator cuff tears, the sensitivity, specificity, positive predictive value, and negative predictive value were 89%, 100%, 100%, and 90%, respectively. For the labral lesions, the sensitivity, specificity, positive predictive value, and negative predictive value were 89%, 95%, 80%, and 97%, respectively. The findings indicated that there was good agreement comparing the MR results obtained using the low-field extremity MR system to the surgical findings for determination of lesions of the rotator cuff and glenoid labrum. Notably, the statistical values determined for the use of this MR system were comparable to those reported in the peer-reviewed literature for the use of whole-body, mid- and high-field-strength MR systems.     

First-time shoulder dislocation: High prevalence of labral injury and age-related differences revealed by MR arthrography

PURPOSE: To evaluate abnormalities and age-related differences after first-time shoulder dislocation. MATERIALS AND METHODS: MRA images of first-time dislocators were assessed for labral-ligamentous-capsular / rotator cuff abnormalities and analyzed the age-related differences (< and >/=30 years old). RESULTS: Sixty-six patients (34 <30 years old vs. 32 >/=30 years; 51 males; all anterior dislocations) were imaged. Forty-eight patients (73%) showed anteroinferior labral avulsion, consisting of: 6% (4/34 vs. 0/32) Perthes; 23% (8/34 vs. 7/32) free ALPSA (anterior labrum periosteal sleeve avulsion) lesion); 6% (1/34 vs. 3/32) adherent ALPSA; 23% (9/34 vs. 6/32) Bankart; 14% (5/34 vs. 4/32) inferiorly displaced avulsed labrum; 2% (1/34 vs. 0/32) GLAD. Extensive labral detachment (extended above 3 o'clock position) was present in 31% (11/28 vs. 4/20). There were 14% (6/34 vs. 3/32) superior labrum anterior-posterior (SLAP) lesion; 27% (1/34 vs. 17/34) rotator cuff tendon tear; 71% (25/34 vs. 22/32) Hill-Sachs defect. Young patients were more likely to have extensive labral avulsions (P = 0.054), but less likely to have rotator cuff tears (P < 0.001). CONCLUSION: A high prevalence and wide variety of labral avulsions after first-time shoulder dislocation, especially adherent ALPSA, inferiorly displaced avulsed labrum, or GLAD lesion, may influence treatment choice and outcome, suggesting a role for early MRA to assist in treatment triage.     

Arthroscopic repair of type II superior labral anterior posterior lesions with and without acromioplasty: a clinical analysis of 50 patients

BACKGROUND: The treatment of type II superior labral anterior posterior (SLAP) lesions remains controversial. Many surgeons are reluctant to combine a SLAP repair with an acromioplasty for fear of postoperative shoulder stiffness and a poor clinical outcome. HYPOTHESIS: A SLAP repair and an acromioplasty done concomitantly may yield acceptable outcomes. Study Design: Case series; Level of evidence, 4. METHODS: We compared the clinical results of 50 patients who had either an isolated type II SLAP repair (SLAP group, 34 patients) or a combined type II SLAP repair and acromioplasty (combined group, 16 patients). Patients were excluded for full-thickness rotator cuff tears or instability. All patients were evaluated with the L'Insalata Functional Shoulder Rating Questionnaire, with the American Shoulder and Elbow Surgeons (ASES) questionnaire, and by subjective evaluation. RESULTS: At an average of 3.4 years postoperatively, the L'Insalata and ASES scores were similar for the 2 groups: 87.1 and 85.8 for the SLAP group and 85.1 and 86.5 for the combined group, respectively (P > .05). Subjectively, only 65% of the patients in the SLAP group reported a "good" or "excellent" satisfaction with the surgery, compared with an 81% "good" or "excellent" satisfaction rating among the patients in the combined group. Seven patients (21%) in the SLAP group had postoperative clinical impingement, compared with no patients (0%) in the combined group (P < .03). CONCLUSIONS: According to our data, these 2 procedures done concomitantly may yield acceptable outcomes. Our findings indicated that a combined type II SLAP repair and acromioplasty had no negative effect clinically and, furthermore, appeared to prevent residual clinical impingement.     

Arthroscopic versus open Bankart repair for traumatic anterior shoulder instability

After more than 15 years of experience, arthroscopic shoulder stabilization is becoming less controversial. Historically, recurrence rates following arthroscopic stabilization have been higher than with open stabilization. Although a negligible advantage may exist in terms of expedited postoperative rehabilitation and improved postoperative recovery of motion, critics suggest that its use in contact athletes be limited. The indications for arthroscopic stabilization are expanding, in part, because of improved understanding of the pathophysiology of shoulder instability. Understanding the mechanism of recurrent instability following arthroscopic stabilization offers clues to how physicians can prevent unsatisfactory results in the future. With newer instrumentation and the ability to thermally treat capsular tissue, coexisting pathology, such as capsular plastic deformation, rotator interval lesions, and unrecognized intra-articular pathology, can now be addressed arthroscopically. The judicious use of these techniques is warranted until long-term study results become available. Ideal patients for arthroscopic Bankart repair have a discrete Bankart lesion; a robust, well-developed IGHL; no significant capsular laxity or intraligamentous injury; and an absence of concomitant intra-articular pathology. Additional findings on MR imaging or CT evidence of a discrete labral lesion and pure unidirectional anterior instability during EUA are also good prognostic indicators for arthroscopic Bankart repair. Arthroscopic criteria that render patients less appropriate for an arthroscopic repair include capsular injury, capsular laxity, a bony Bankart lesion, glenohumeral arthritis, and a rotator cuff tear. The authors' believe that either absent or patulous, poorly developed glenohumeral ligaments represent a poor prognostic indicator for a successful outcome following standard arthroscopic Bankart repair. Individuals with poor-quality tissue are more predictably managed using open capsulorrhaphy. Patients with pathologic ligamentous laxity in the absence of a Bankart lesion or any apparent intraligamentous injury to the IGHL are also good candidates for treatment with an open capsulorrhaphy. Findings determined from a thorough physical examination, EUA, and the pathology appreciated during diagnostic arthroscopy help to appropriately choose the surgical procedure that effectively addresses pathology in patients who present with recurrent traumatic anterior instability. Patient preferences and surgical experience are important determinants of procedure selection, and current arthroscopic techniques lack the versatility to uniformly address the entire spectrum of pathology that may be associated with traumatic anterior shoulder instability. Surgeons should always be prepared to convert to an open-stabilization technique if the arthroscopic technique is deficient in addressing all pathology identified at the time of surgery.     

The use of split deltoid-flap in the treatment of massive rotator cuff defects: a retrospective study of 61 patients

Massive and irreparable rotator cuff tears are a challenge for the orthopaedic surgeon. The purpose of this study was to report our experience with the treatment of massive and irreparable defects of the rotator cuff with a modified deltoid split transfer. Between 1996 and 2004, for all patients suffering from full-thickness tears of the rotator cuff (>5 cm tears in diameter, involving two or more tendons) were operated with a modified deltoid split transfer. A total of 61 patients (39 females and 22 males; age 61.9: range 49-75 years) were operated. Duration of symptoms before surgery averaged 9.6 months (range 3.5-14 months). The patients were followed for an average of 46 months (range 24-64 months). The operation included an arthroscopic evaluation, acromioplasty with resection of the lateral clavicular end, resection of the acromioclavicular joint and where necessary biceps tenodesis. The cuff defect was repaired by transfer of half thickness anterior deltoid-flap (3 cm x 5 cm) into the defect. All patients were evaluated both preoperatively and postoperatively with regard to pain, ability to perform activities of daily life, range of motion, strength and satisfaction. The patients subjectively rated their results-49 (80%) excellent or good outcome, seven moderate and five poor. Preoperatively, the Constant amounted 33.5 +/- 7.74 points. At follow-up, the score significantly increased to 77.57 +/- 19.74 points. The acromiohumeral distance increased from 5.1 +/- 1.4 mm to 9.1 +/- 1.5 mm. Pain free flexion improved from an average 90 degrees to an average 165 degrees (P < 0.01), and abduction improved from an average 110 degrees to an average 160 degrees (P < 0.01). The mean external rotation increased from 40 degrees to 65 degrees (P < 0.01), and internal rotation increased from 50 degrees to 70 degrees (P = 0.06). In the MRI and ultrasound examination, all patients had intact flap, except the three patients with flap necrosis. There were eight complications-three haematomas, two superficial wound infections which did not influence the outcome, and three fibrotic transformation after an early aseptic necrosis of the deltoid flap, which were re-operated. This technique is easy to perform, and it is possible to obtain a satisfactory outcome after repair of massive tears of the rotator cuff. A substantial decrease of pain, increased stability, an increase range of motion and strength can be achieved, with proper rehabilitation.     

Quantitative assessment of glenohumeral translation after anterior shoulder dislocation and subsequent arthroscopic bankart repair

BACKGROUND: During the past decade, developments in arthroscopic technology have made arthroscopic repair of labral lesions feasible. However, results with the use of the transglenoid suture technique, or with the use of bioabsorbable tacks, have remained variable in the literature, and the recurrence rates are still inferior to those of open Bankart repair. HYPOTHESIS: Arthroscopic Bankart repair with suture anchors can re-create translational and rotational range of motion of the intact glenohumeral joint, and the number of preoperative dislocations has an influence on the result. STUDY DESIGN: Controlled laboratory study. MATERIALS: Twelve cadaveric shoulders were tested in a robot-assisted shoulder simulator. Anterior and posterior translation and external rotation were measured for intact, dislocated (shoulders were randomly selected to 1 of 3 groups, which were dislocated 1, 3, or 7 times), and repaired conditions at 0 degrees and 90 degrees of glenohumeral elevation. RESULTS: After shoulder dislocation, a significant increase was found in translation and rotation, confirming the creation of a traumatic shoulder instability model. Further testing of the specimen revealed that translational and rotational ranges of motion were reduced by arthroscopic Bankart repair at both testing positions. External rotation was decreased significantly at 0 degrees and 90 degrees of abduction. No significant differences were found between the 3 dislocation groups. CONCLUSION: The results demonstrate a sufficient biomechanical performance of arthroscopic Bankart repair using suture anchors in a traumatic anterior shoulder instability model. With the numbers available, no relationship was found between the number of dislocations and the postoperative result concerning translational or rotational motion. CLINICAL RELEVANCE: Glenohumeral translation and rotation after arthroscopic Bankart repair with use of suture anchors approached near normal values, confirming the clinical success of this technique.     

A prospective comparison study of double contrast computed tomography (CT) arthrography and arthroscopy of the shoulder

Thirty consecutive patients who underwent double contrast CT arthrography prior to shoulder arthroscopy were prospectively studied. Results from both studies were recorded with the radiologist blinded to the arthroscopic findings when making the final CT reading. The sensitivity, specificity, and accuracy, respectively, of CT arthrography findings compared to arthroscopy were 50%, 100%, 96% for rotator cuff; 66%, 100% 96% for bicipital labral complex; 100%, 100%, 100% for loose bodies; 50%, 100% 93% for Hill-Sachs lesions; 90%, 73%, 83% for anterior labral defects; and 100%, 100%, 100% for posterior labral defects. We conclude that shoulder arthroscopy accurately delineates abnormalities of the anterior and posterior labrum, bicipital labral complex, rotator cuff, joint synovium, and humeral head. CT arthrography accurately delineates capsular redundancy, loose bodies, hardware around joints, and bony glenoid rim abnormalities.     

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.     

Arthroscopic repairof partial-thickness rotator cuff tears and slap lesions in professional baseball players

Our understanding of the conditions that affect the throwing shoulder continues to evolve. Surgical techniques also have advanced, and the arthroscopic repair of rotator cuff tears, superior labrum anterior to posterior (SLAP) lesions, and capsular ligament attenuation is now possible.     

MRI of internal impingement of the shoulder

OBJECTIVE: Internal impingement is a condition that occurs in athletes in which the shoulder is put in extreme abduction and external rotation during overhead movements. During this motion, the posterior fibers of the supraspinatus tendon, anterior fibers of the infraspinatus tendon, or both can get impinged between the humeral head and the posterior glenoid. The purpose of this study was to evaluate the ability of MRI to show the findings of internal impingement of the shoulder. CONCLUSION: As opposed to our six patients with clinically and surgically diagnosed internal impingement, the control patients had isolated pathology in the rotator cuff, labrum, or humeral head. We found that the constellation of findings of undersurface tears of the supraspinatus or infraspinatus tendon and cystic changes in the posterior aspect of the humeral head associated with posterosuperior labral pathology is a consistent finding diagnostic of internal impingement.     

Ultrasonographic and MR diagnosis of rotator cuff disorders & shoulder joint instability

Objective

To evaluate the role and efficacy of U/S and MR in diagnosis of rotator cuff disorders and shoulder joint instability.

Patients and methods

This study included 30 patients with shoulder pain and/or movement limitation. They underwent shoulder U/S examination followed by MR examination. The U/S & MR diagnostic criteria of each patient were analyzed, compared and correlated with arthroscopic and/or orthopedic surgical findings.

Results

15 patients had with rotator cuff disorders 15/30 (50%) and 11 patients had shoulder instability 11/30 (36.7%). Out of 15 patients with rotator cuff disorders, 12 patients had rotator cuff tears 12/15 (80%) and 3 patients had tendenosis 3/15(20%). The supraspinatus muscle was involved in all cases (100%), without a significant comparable difference between U/S and MR. Out of 11 patients with shoulder instability 8 patients had anterior labral tear 8/11 (72.7%); 2 patients had superior labral tear 2/11 (18.2%) and only one patient with posterior labral tear.

Conclusion

U/S and MRI are valid diagnostic modalities in detecting, characterizing and discriminating the rotator cuff disorders, with no significant comparable difference. U/S has many challenges in patients with shoulder instability, while MR provides accurate diagnosis even without contrast.     

MR arthrography of the shoulder: comparison with conventional MR imaging

Twenty-three patients underwent both conventional MR imaging of the shoulder and MR shoulder arthrography for clinically suspected labral or rotator cuff abnormalities. Images obtained before and after contrast administration were studied independently, and without knowledge of clinical findings, by two radiologists for the presence of abnormalities of the glenoid labrum or rotator cuff. Results were correlated with surgical findings in all patients. Nine patients had surgically proved labral tears. MR arthrography detected all nine labral abnormalities, while six of the nine were missed on conventional MR imaging. Fourteen patients had surgically proved rotator cuff tears. MR arthrography detected 11 of the 14 tears and missed three partial tears on the bursal surface. Conventional MR imaging detected nine cuff tears and missed five tears; two of these were complete rotator cuff tears and three were partial tears of the undersurface of the rotator cuff. Our results suggest that MR arthrography enhances the accuracy of MR in the evaluation of the glenoid labrum and rotator cuff tendon.     

Outcome and structural integrity after arthroscopic rotator cuff repair using 2 rows of fixation: minimum 2-year follow-up

BACKGROUND: Although arthroscopic repairs of the rotator cuff are becoming increasingly popular, security of fixation remains a concern. Two-row repairs have been described, but clinical outcome reports have primarily involved open techniques. HYPOTHESIS: An arthroscopic repair technique that uses 2 rows of fixation produces satisfactory outcome and structural integrity by ultrasonography. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Forty-eight patients (52 shoulders) with a full-thickness, but fully reducible, rotator cuff tear who met the inclusion criteria were treated with an arthroscopic rotator cuff repair using 2 rows of suture anchors. The mean tear size was 2.47 cm (range, 1-4 cm). Patients were evaluated by subjective functional assessment (L'Insalata Shoulder Rating Questionnaire), clinical examination, including measured strength testing, and ultrasonography. RESULTS: At a mean follow-up of 30 months (minimum of 2 years), functional scores improved from a mean of 42 preoperatively to 93 postoperatively (P < .001). Active range of motion was increased in all measured planes (P < .001). Strength was also increased in elevation (P < .001), external rotation (P < .001), and internal rotation (P = .033). Nine of the 52 shoulders (17%) had evidence of retear or persistent defect on postoperative ultrasonography. There were no differences detected in functional scores between those with an intact repair and those with a defect, but those with an intact repair were stronger in elevation (P = .006) and external rotation (P = .001). CONCLUSION: An arthroscopic 2-row rotator cuff repair produces excellent functional outcome and repair integrity comparable with previously reported open repairs. Presence of a defect after repair did not appear to affect patient-reported function and return to preinjury activity but did affect measured strength.     

The proximal biceps as a pain generator and results of tenotomy

Many palliative interventions have been proposed for patients in whom rotator cuff repair is not feasible as a result of advanced fatty infiltration, definitive loss of tendons, and proximal humeral migration. The long head of the biceps tendon has been proposed as a source of pain in patients with rotator cuff tears. This article presents a review of current concepts on the rationale for arthroscopic biceps tenotomy or tenodesis, and evaluates the objective, subjective, and radiographic results of these palliative procedures. On the basis of different studies, it seems that isolated arthroscopic biceps tenotomy or tenodesis is a valuable option for the treatment of rotator cuff tears in selected patients. Although it does not improve shoulder strength, tenotomy or tenodesis reduces pain and improves the functional range of motion with a high degree of patient satisfaction. However, the progressive radiographic changes that occur with long standing rotator cuff tears are not altered.     

Anterior versus posterior, and rim-rent rotator cuff tears: prevalence and MR sensitivity

Purpose. To determine the relative distribution of the locations of rotator cuff tears, and the sensitivity of anterior versus posterior tears on MR images. Patients and methods. We identified 110 consecutive patients who had a shoulder MR and either a partial-thickness or a small full-thickness rotator cuff tear diagnosed at arthroscopy. From the arthroscopy videotapes, we classified the tears as centered in the anterior or posterior half of the cuff, and as either in the critical zone or adjacent to the bony insertion. The original MR interpretation was compared with the arthroscopic findings. MR sensitivity and patient age were compared between patients with tears in the anterior and posterior halves of the cuff. In addition, in patients with partial tears less than 2 cm in diameter, an age comparison between those with tears in the critical zone and those with articular surface tears adjacent to the bony insertion (rim-rent tear) was performed. Results. The tear was centered in the anterior half of the rotator cuff in 79% of the patients younger than 36 years old, and in 89% of the patients 36 years old and over. The average age of the patients with tears in the anterior half (44 years) was not significantly different from the average age of those with posterior tears (40 years)(P=0.23). The sensitivity of MR for anterior tears was 0.69, and for posterior tears it was 0.56 (P=0.17). The average age of the 9 patients with rim-rent tears was 31 years, while that of the 28 patients with similarly-sized partial tears not involving the insertion was 40 years old (P=0.048). Five of the nine rim-rent tears (0.56) were interpreted correctly on the original MR report; two of the other tears were misinterpreted as intratendinous fluid but were diagnosable in retrospect. Conclusion. Even in patients less than 36 years old, most partial and small full-thickness rotator cuff tears are centered in the anterior half of the supraspinatus. Although our figure for MR sensitivity for these tears is lower than in recent articles, we found no significant difference between the sensitivity of MR for diagnosing posterior tears versus tears in the anterior half of the supraspinatus tendon. Rim-rent tears can be mistaken for intratendinous signal, and should be carefully looked for in younger patients with shoulder pain.     

The partial-thickness rotator cuff tear: is acromioplasty without repair sufficient?

We evaluated the clinical outcome of arthroscopic acromioplasty and debridement in 162 patients who had either normal rotator cuffs, grade 1 (frayed tendon) partial-thickness tears, or grade 2 (less than 50% of the tendon) partial-thickness tears. The mean time from surgery to the response to the L'Insalata outcome questionnaire was 52.7 months (4.5 years) among the 105 respondents (107 shoulders). The mean score was 90 points; eight patients (8%) scored less than 70 points (range, 30 to 65.5), and their treatment failed early on. The patients with grade 2B (bursal) partial-thickness rotator cuff tears had a significantly higher failure rate (38%). Although the clinical outcome of patients with partial-thickness tears of the rotator cuff comprising less than 50% of the tendon (grade 1 and 2) was not significantly different from that of patients without partial rotator cuff tears, the subgroup of patients with grade 2B partial tears had a statistically significantly higher failure rate and may have been better served with primary repair. With follow-up to 10 years, there was no evidence that clinically relevant or symptomatic intrinsic rotator cuff pathologic conditions progress in those patients with partial-thickness tears treated with arthroscopic anterior acromioplasty.     

Magnetic resonance imaging in glenohumeral instability

The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability.Magnetic resonance (MR) imaging,and more recently,MR arthrography,have become the essential investigation modalities of glenohumeral instability,especially for pre-procedure evaluation before arthroscopic surgery.Injuries associated with glenohumeral instability are variable,and can involve the bones,the labor-ligamentous components,or the rotator cuff.Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament,in the form of Bankart lesion and its variants;whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion.Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion.This article reviews the relevant anatomy in brief,the MR imaging technique and the arthrographic technique,and describes the MR findings in each type of instability as well as common imaging pitfalls.