Superior labrum anterior-posterior lesions: diagnosis with MR arthrography of the shoulder

PURPOSE: To determine the accuracy of magnetic resonance (MR) arthrography in the diagnosis of superior labrum anterior-posterior (SLAP) lesions of the shoulder. MATERIALS AND METHODS: From January 1995 to June 1998, MR arthrography of the shoulder was performed in 159 patients with a history of chronic shoulder pain or instability. Fifty-two patients underwent arthroscopy or open surgery 12 days to 5 months after MR arthrography. Diagnostic criteria for SLAP lesion included marked fraying of the articular aspect of the labrum, biceps anchor avulsion, inferiorly displaced bucket handle fragment, and extension of the tear into the biceps tendon fibers. Surgical findings were correlated with those from MR arthrography. RESULTS: SLAP injuries were diagnosed at surgery in 19 of the 52 patients (37%). Six of the 19 lesions (32%) were classified as type I, nine (47%) as type II, one (5%) as type III, and three (16%) as type IV. MR arthrography had a sensitivity of 89% (17 of 19 patients), a specificity of 91% (30 of 33 patients), and an accuracy of 90% (47 of 52 patients). The MR arthrographic classification showed correlation with the arthroscopic or surgical classification in 13 of 17 patients (76%) in whom SLAP lesions were diagnosed at MR arthrography. CONCLUSION: MR arthrography is a useful and accurate technique in the diagnosis of SLAP lesions of the shoulder. MR arthrography provides pertinent preoperative information with regard to the exact location of tears and grade of involvement of the biceps tendon.     

Anterior shoulder instability: accuracy of MR arthrography in the classification of anteroinferior labroligamentous injuries

PURPOSE: To retrospectively evaluate the accuracy of magnetic resonance (MR) arthrography in the classification of anteroinferior labroligamentous injuries by using arthroscopy as the reference standard. MATERIALS AND METHODS: Ethical committee approval and informed consent were obtained. MR arthrograms obtained in 205 patients, including a study group of 104 patients (74 male and 30 female; mean age, 28.2 years) with arthroscopically proved labroligamentous injuries and a control group of 101 patients (65 male and 36 female; mean age, 31.4 years) with intact labroligamentous complex, were reviewed in random order. MR arthrograms were analyzed for the presence and type (Bankart, anterior labral periosteal sleeve avulsion [ALPSA], Perthes, glenolabral articular disruption [GLAD], or nonclassifiable lesion) of labroligamentous injuries by two radiologists in consensus. Results were compared with arthroscopic findings. Sensitivity, specificity, accuracy, and corresponding 95% confidence intervals for the detection and classification of anteroinferior labroligamentous lesions with MR arthrography were calculated. RESULTS: At arthroscopy, 104 anteroinferior labroligamentous lesions were diagnosed, including 44 Bankart lesions, 22 ALPSA lesions, 12 Perthes lesions, and three GLAD lesions. Twenty-three labral lesions were nonclassifiable at arthroscopy, all of which occurred after a history of chronic instability. Nineteen (83%) of these 23 lesions were also nonclassifiable at MR arthrography. With arthroscopy used as the reference standard, labroligamentous lesions were detected and correctly classified at MR arthrography with sensitivities of 88% and 77%, specificities of 91% and 91%, and accuracies of 89% and 84%, respectively. Bankart, ALPSA, and Perthes lesions were correctly classified in 80%, 77%, and 50% of cases, respectively. The three GLAD lesions were all correctly assessed. CONCLUSION: MR arthrography is accurate in enabling classification of acute and chronic anteroinferior labroligamentous injuries, although correct interpretation of Perthes lesions remains difficult.     

Superior labral anterior posterior (SLAP) lesions of the glenoid labrum: reliability and accuracy of MR arthrography for diagnosis

PURPOSE: To determine the reliability and accuracy of magnetic resonance (MR) arthrography for the diagnosis of superior labral anterior posterior (SLAP) tears. MATERIALS AND METHODS: The MR arthrograms in 80 patients who underwent arthroscopy and MR arthrography during a 54-month period were retrospectively reviewed. MR arthrograms were independently scored by three observers for the presence and type of SLAP lesion. Type I SLAP lesions were regarded as negative as they most often are not clinically relevant. Interobserver agreement for detection of SLAP lesions was calculated by using kappa coefficients. The differences in areas under the receiver operating characteristic (ROC) curves were assessed with a univariate z score test. RESULTS: At arthroscopy, there were 25 SLAP tears: type II (n = 22), type III (n = 2), and type IV (n = 1). Sensitivity, specificity, and accuracy of each reader were 92%, 84%, and 86%; 92%, 82%, and 85%; and 84%, 69%, and 74%, respectively. Interobserver agreement for SLAP tears was substantial (kappa = 0.77) to moderate (kappa = 0.52, kappa = 0.44). The areas under the ROC curves for each reader were 0.94, 0.93, and 0.83, which were not significantly different. CONCLUSION: MR arthrography of the shoulder is reliable and accurate for detection of SLAP tears.     

上方盂唇前后向撕裂的肩关节MR造影评价

目的 评价肩关节MR造影对上方盂唇前后向撕裂(SLAP损伤)的诊断价值.方法 由2名影像诊断医师独立回顾分析137例经肩关节镜证实的肩关节造影MR图像,判定有无SLAP损伤,并进行分型.SLAP损伤分4型:Ⅰ型为上盂唇毛糙,Ⅱ型为肱二头肌腱盂唇复合体从关节孟撕裂,Ⅲ型为上盂唇桶柄状撕裂,Ⅳ型为上盂唇桶柄状撕裂并同时累及肱二头肌长头腱.计算肩关节MR造影对SLAP损伤的敏感度、特异度和准确度,以及与肩关节镜分型的符合率.采用Kappa统计计算2名影像诊断医师评价的一致性.结果 137例患者中,肩关节镜证实SLAP损伤59例,包括SLAP损伤Ⅰ型6例(10.2%)、Ⅱ型50例(84.7%)、Ⅲ型3例(5.1%).肩关节MR造影的敏感度、特异度和准确度医师甲分别为86.4%(51/59)、78.2%(61/78)和81.8%(112/137),医师乙分别为88.1%(52/59)、84.6%(66/78)和86.1%(118/137).2名影像诊断医师的评价一致性极好(K=0.796).肩关节MR造影与肩关节镜的分型符合率医师甲为83.1%(49/59),医师乙为79.7%(47/59).结论 肩关节MR造影是评价SLAP损伤比较可靠的影像方法.     

Inter- and intraobserver variability of MR arthrography in the detection and classification of superior labral anterior posterior (SLAP) lesions: evaluation in 78 cases with arthroscopic correlation

Purpose

The purpose of this study was to determine inter- and intraobserver variability of MR arthrography of the shoulder in the detection and classification of superior labral anterior posterior (SLAP) lesions.

Methods

MR arthrograms of 78 patients who underwent MR arthrography before arthroscopy were retrospectively analysed by three blinded readers for the presence and type of SLAP lesions. MR arthrograms were reviewed twice by each reader with a time interval of 4 months between the two readings. Inter- and intraobserver agreement for detection and classification of SLAP lesions were calculated using κ coefficients.

Results

Arthroscopy confirmed 48 SLAP lesions: type I (n?=?4), type II (n?=?37), type III (n?=?3), type IV (n?=?4). Sensitivity and specificity for detecting SLAP lesions with MR arthrography for each reader were 88.6%/93.3%, 90.9%/80.0% and 86.4%/76.7%. MR arthrographic and arthroscopic grading were concurrent for 72.7%, 68.2% and 70.5% of SLAP lesions for readers 1–3, respectively. Interobserver agreement was excellent (κ?=?0.82) for detection and substantial (κ?=?0.63) for classification of SLAP lesions. For each reader intraobserver agreement was excellent for detection (κ?=?0.93, κ?=?0.97, κ?=?0.97) and classification (κ?=?0.94, κ?=?0.84, κ?=?0.93) of SLAP lesions.

Conclusion

MR arthrography allows reliable and accurate detection of SLAP lesions. In addition, SLAP lesions can be diagnosed and classified with substantial to excellent inter- and intraobserver agreement.     

Diagnosis of SLAP lesions with Grashey-view arthrography

OBJECTIVE: To examine the accuracy of Grashey views obtained during shoulder arthrography in the diagnosis of clinically relevant superior labrum anterior-posterior (SLAP) lesions. DESIGN AND PATIENTS: Grashey views obtained during diagnostic arthrography (conventional and MR) were used to examine the superior labrum. Twenty-eight of 118 shoulder arthrograms obtained during a 27-month period fulfilled study criteria and were correlated for accuracy using arthroscopically confirmed grade 2-4 SLAP lesions as the standard of reference. Arthrograms were graded using the consensus method. Prevalence, sensitivity, specificity, and accuracy were 21%, 50%, 86%, and 79%. The appearance of the superior labrum on the Grashey view was compared subjectively with MR arthrography. Sources of errors were analyzed. CONCLUSION: Grashey views obtained during shoulder arthrography can diagnose clinically relevant SLAP lesions with moderately high specificity, moderate accuracy, and limited sensitivity. Findings on the Grashey view closely resemble those seen on coronal oblique MR arthrography. Grashey views should be considered in patients undergoing shoulder arthrography.     

MR arthrographic findings of SLAP lesion type V

PURPOSE: The purpose of this study was to determine the findings of MR arthrography of the shoulder and to assess the role of MR arthrography in the diagnosis of superior labrum anterior to posterior (SLAP) lesion type V. METHODS AND MATERIALS: Two radiologists retrospectively reviewed fat-suppressed T1-weighted MR arthrography images of six patients who were diagnosed with SLAP lesion type V by arthroscopy. Each imaging plane, including the transverse, oblique coronal, oblique sagittal, and oblique transverse in abductor external rotation (ABER) position were evaluated for the following three findings: tear of the superior labrum at biceps tendon insertion, Bankart lesion, and continuity of the two former findings. RESULTS: Tear of the superior labrum was shown in all patients on oblique coronal images. Bankart lesion was noted in five patients on the transverse images and in four on the oblique sagittal images. On the oblique transverse images in ABER position, Bankart lesion was shown in all patients. The continuity of the two former findings was noted in three patients on the ABER positioned images. Therefore, three patients could be diagnosed as having SLAP lesion type V by MR arthrography in our series. CONCLUSION: It is difficult to detect all three findings of SLAP lesion type V in one imaging plane, however, a combination of multi-directional images may increase the feasibility of MR arthrography in diagnosing SLAP lesion type V.     

Shoulder MR arthrography: which patient group benefits most?

OBJECTIVE: We sought to compare the diagnostic accuracy of conventional MRI versus MR arthrography of the shoulder in the assessment of high-performance athletes (professional baseball players) and to compare our findings in these patients with the conventional MRI and MR arthrographic findings in an age-matched control group of nonprofessional athletes. MATERIALS AND METHODS: Conventional MRI and MR arthrographic examinations of the shoulder in 20 consecutive professional baseball players with shoulder pain were reviewed retrospectively by two musculoskeletal radiologists in consensus. These interpretations were compared with retrospective consensus interpretations of conventional MRI and MR arthrographic examinations of the shoulder obtained in a control group of 50 consecutive nonprofessional athletes with shoulder pain. MR images were assessed for full- or partial-thickness supraspinatus tendon tears, superior labral anteroposterior (SLAP) tears, and anterior or posterior labral tears. RESULTS: In the 20 consecutive professional athlete patients, two full-thickness and six partial-thickness undersurface supraspinatus tendon tears were seen on MR arthrography but not seen on conventional MRI as well as six SLAP tears, two anterior labral tears, and one posterior labral tear. Three patients had both SLAP tears and full- or partial-thickness supraspinatus tendon tears. Of 14 patients with findings on MR arthrography that were not seen on MRI, 11 had arthroscopic correlation. In all 11, arthroscopic findings confirmed findings on MR arthrography. In the group of 50 nonprofessional athlete patients, five had additional findings on MR arthrography not seen on conventional MRI: two anterior labral tears, two partial-thickness supraspinatus tendon tears, and two SLAP tears. One patient had both a partial-thickness supraspinatus tendon tear and a SLAP tear seen on MR arthrography. The five patients with additional findings on MR arthrography had arthroscopy. In all five, arthroscopic findings confirmed the findings on MR arthrography. CONCLUSION: MR arthrography is considerably more sensitive for detection of partial-thickness supraspinatus tears and labral tears than conventional MRI. MR arthrography showed injuries in addition to those seen on conventional MRI in 14 of 20 patients in the high-performance athlete group. These results suggest high-performance athletes may be a subgroup of patients for whom MR arthrography yields considerably more diagnostic information than conventional MRI.     

Superior labral anteroposterior lesions: MR arthrography with arm traction.

OBJECTIVE: The purpose of this study was to investigate the efficacy of arm traction combined with MR arthrography in the evaluation of superior labral anteroposterior (SLAP) lesions. MATERIALS AND METHODS: Cadaveric shoulders were studied with a 1.5-T MR imaging unit with the arm externally rotated. Fifteen milliliters of a gadolinium-containing contrast agent were injected into the glenohumeral joint. Twenty-four sets of images of cadaveric joints were evaluated independently by two observers. These sets consisted of MR arthrographic images obtained with traction (applied to the wrist using 1- to 3-kg weights) and without traction in five shoulders in which SLAP lesions had been excluded arthroscopically or by cadaveric sectioning; and MR arthrographic images obtained with and without traction in seven shoulders in which various types of SLAP lesions had been created arthroscopically and later confirmed by cadaveric sectioning. RESULTS: Analysis of the data indicated that MR arthrography in combination with arm traction and external rotation improved diagnostic accuracy with regard to identification and categorization of SLAP lesions when compared with studies made without traction. CONCLUSION: The combination of MR arthrography and arm traction with the shoulder in external rotation provides a more effective approach for detection of SLAP lesions than does similar MR arthrography performed without arm traction.     

Variants of the superior labrum and labro-bicipital complex: a comparative study of shoulder specimens using MR arthrography, multi-slice CT arthrography and anatomical dissection

The purpose of the present study was to evaluate the anatomical variability of the superior labrum and to compare the value of MR arthrography and multi-slice CT arthrography in the diagnosis of variants of the labro-bicipital complex. Forty-three human shoulder specimens (age range and mean age at death, 61–89 years and 78.3 years) were examined with the use of MR arthrography and multi-slice CT arthrography prior to joint exploration and macroscopic inspection of the superior labrum and labro-bicipital complex. Two radiologists evaluated MR and CT arthrograms, and the results were compared with macroscopic assessments. Anatomical dissection of all shoulder specimens revealed a sublabral recess in 32/43 (74%) cases. The attachment of the superior labrum was categorised as type 1 in ten (23%) cases, as type 2 in eight (19%), as type 3 in ten (23%), and as type 4 in 14 (33%) cases. One superior labrum showed detachment consistent with a superior labral anteroposterior (SLAP) type 3 lesion. On MR arthrography and CT arthrography the attachment of the superior labrum was categorised in concordance with macroscopic assessments in 79% and 84% of cases, respectively. The anteroposterior extension of sublabral recesses was accurately determined with MR and CT arthrography in 59% and 81% of cases, respectively. The attachment of the superior labrum shows considerable variability. Thus, exact depiction of variants is essential in order to avoid the false positive diagnosis of a superior labral tear (SLAP or Andrews lesion). Both, MR arthrography and multi-slice CT arthrography were effective in the detection and classification of sublabral recesses.     

A new pain provocation test for superior labral tears of the shoulder

We prospectively evaluated the usefulness of a new pain provocation test to diagnose superior labral tears in 32 patients with diagnosed throwing injuries of the shoulder. Results of the pain provocation test were compared with findings on magnetic resonance arthrography (all 32 patients) and arthroscopic examination (15 patients). In 22 patients, detachment of the superior labrum was observed on arthrograms, and all of them had positive results on the new pain provocation test. Nine of the other 10 patients had negative results on the new pain provocation test. However, 1 of the 10 patients had a positive result. Eleven of 15 patients were found to have superior labral lesions arthroscopically, and all of them were classified as type II superior labral anterior posterior lesions. All the 11 patients had positive pain provocation tests. The other four patients without superior labral tears on arthroscopic findings had negative results on the new pain provocation test. The new pain provocation test identified all patients with detachment of the superior labrum confirmed by magnetic resonance arthrography, for a sensitivity of 100%, a specificity of 90%, and an accuracy of 97%. Results of the new pain provocation test were in accord with arthroscopic findings in the 15 patients who underwent arthroscopic examination.     

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.     

3D-SPACE序列在肩关节MR造影中评估上盂唇前后撕裂

目的：评价肩关节 MR造影三维各向同性脂肪抑制快速自旋回波（SPACE）序列对上盂唇前后撕裂（SLAP损伤）的诊断价值。方法：影像诊断医师回顾性分析经关节镜证实的肩关节 MR 造影图像,判定有无SLAP 损伤及分型,对比常规二维序列和SPACE序列对SLAP损伤的敏感度、特异度及准确率,比较常规二维序列与SPACE 序列的诊断价值。结果：肩关节镜证实SLAP损伤12例,肩关节 MR造影SPACE序列与常规二维序列对SLAP 损伤的敏感度分别为83．33％（10/12）及91．67％（11/12）,特异度分别为81．25％（13/16）及87．50％（14/16）,准确度分别为82．14％（23/28）及89．29％（25/28）。SPACE序列与常规二维序列对 SLAP 损伤的诊断效能无明显统计学差异（P＞0．05）。结论：肩关节MR造影中SPACE序列是评价SLAP损伤准确、可靠的影像学方法。     

MR-arthrography in superior instability of the shoulder: correlation with arthroscopy

Purpose

This study was undertaken to evaluate magnetic resonance (MR) arthrography in the detection and classification of lesions that may cause superior instability.

Materials and methods

Forty-two consecutive patients with clinical signs of chronic superior instability of the shoulder underwent MR arthrography followed by arthroscopic surgery. For each patient we retrospectively reviewed the MR arthrography and surgical findings.

Results

We detected 31 superior labral anterior posterior (SLAP) lesions, all confirmed on arthroscopy with three cases of underestimation: in the detection of SLAP lesions, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of MR arthrography were 100%; in the evaluation of the type of SLAP lesion, sensitivity was 100%, specificity was 78.5%, accuracy was 92.8%, PPV was 71.7% and NPV was 100%. All cases of capsular laxity (13/42) and biceps tendon lesions (3/42) were confirmed on arthroscopy with sensitivity, specificity, accuracy, PPV and NPV of 100%. Eleven cuff lesions were detected on MR arthrography, 10 of which confirmed at arthroscopy: sensitivity was 100%, specificity was 96.8%, accuracy was 97.6%, PPV was 90.9% and NPV was 100%. Associated lesions were found in 38/42 patients.

Conclusions

Superior instability is frequently associated with different anatomical variants or pathological conditions, such as SLAP lesions. The role of MR arthrography is to describe the key features of lesions affecting the superior portion of the shoulder, including location, morphology, extent, and associated injuries and leanatomical variants and to correlate these features with clinical symptoms.     

SLAP tears of the glenoid labrum in contact athletes.

OBJECTIVE: To describe the distribution and clinical presentation of labral injuries in rugby players and the time taken for them to return to sports. DESIGN: Retrospective cohort study. SETTING: Busy shoulder practice in the North West of England, treating a large number of professional athletes. PATIENTS: A review of 51 shoulder arthroscopies performed on professional rugby players over a 35 month period. All patients diagnosed with a SLAP lesion at arthroscopy were identified. Eighteen patients had a documented SLAP tear; this group represented our study population. INTERVENTIONS: Arthroscopic debridement and/or stabilization was carried out for all labral injuries using Panaloc anchors and No. 2 PDS via a 2 portal technique. MAIN OUTCOME MEASUREMENTS: Classification of injury, Satisfaction, Time to return to play. RESULTS: The incidence of SLAP tears in our study population was 35%. There were 11 isolated SLAP tears (61%), 3 SLAP tears associated with a Bankart lesion (17%), 2 SLAP tears associated with a posterior labral lesion (11%), and 2 SLAP tears associated with an anterior and posterior labral injuries (11%). Of the 18 SLAP tears, 14 (78%) were type 2, 3 (17%) were type 3, and 1 (5%) was type 4. None of the patients with a SLAP tear presented with symptoms of instability. MR Arthrogram had a 76% sensitivity for detecting SLAP tears. By 6 months postsurgery, 89% of patients were satisfied. Patients with isolated SLAP tears were the quickest to return to sports, at an average of 2.6 months postsurgery. CONCLUSIONS: SLAP tears are a common injury in rugby players. These can often be diagnosed with MR arthrography. Arthroscopic repair is associated with excellent results and early return to sports.     

SLAP lesions: a treatment algorithm

Tears of the superior labrum involving the biceps anchor are a common entity, especially in athletes, and may highly impair shoulder function. If conservative treatment fails, successful arthroscopic repair of symptomatic SLAP lesions has been described in the literature particularly for young athletes. However, the results in throwing athletes are less successful with a significant amount of patients who will not regain their pre-injury level of performance. The clinical results of SLAP repairs in middle-aged and older patients are mixed, with worse results and higher revision rates as compared to younger patients. In this population, tenotomy or tenodesis of the biceps tendon is a viable alternative to SLAP repairs in order to improve clinical outcomes. The present article introduces a treatment algorithm for SLAP lesions based upon the recent literature as well as the authors’ clinical experience. The type of lesion, age of patient, concomitant lesions, and functional requirements, as well as sport activity level of the patient, need to be considered. Moreover, normal variations and degenerative changes in the SLAP complex have to be distinguished from “true” SLAP lesions in order to improve results and avoid overtreatment. The suggestion for a treatment algorithm includes: type I: conservative treatment or arthroscopic debridement, type II: SLAP repair or biceps tenotomy/tenodesis, type III: resection of the instable bucket-handle tear, type IV: SLAP repair (biceps tenotomy/tenodesis if >50 % of biceps tendon is affected), type V: Bankart repair and SLAP repair, type VI: resection of the flap and SLAP repair, and type VII: refixation of the anterosuperior labrum and SLAP repair.     

MR arthrographic findings in tenosynovitis of the long bicipital tendon of the shoulder

 Purpose. To assess the MR arthrographic findings of bicipital tenosynovitis in correlation with arthroscopy. Design and patients. The shoulder MR arthrographies of 500 consecutive patients were retrospectively analyzed for signs of bicipital tenosynovitis and associated pathologies. Forty patients (8%) had MR evidence of bicipital tenosynovitis, but only 17 (3%) with arthroscopic confirmation were included in the study. The MR findings in these patients were compared with those of 10 patients with rotator cuff lesions but arthroscopically normal long biceps tendons. MR arthrography was performed with 10–15 ml of a 250 mmol/l gadoterate meglumine (Gd-DOTA) solution injected under fluoroscopic guidance, and transaxial, oblique coronal and sagittal MR sequences were obtained. Results. All 17 patients showed one or more abnormal findings: signal increase in the tendon with or without fusiform distension was seen in 12, surface irregularities in six, adhesions in 11 and noncommunicating effusions of the tendon sheath in six. Associated abnormalities of the rotator cuff were present in 16 while the seventeenth patient had glenohumeral synovitis without rotator cuff pathology. MR arthrograms correlated with arthroscopic findings in the joint but comparison was not possible in the intertubercular groove portion of the biceps tendon. None of the 10 patients with an arthroscopically normal biceps tendon showed any of the MR findings of bicipital tenosynovitis. Conclusion. Bicipital tenosynovitis is detectable by MR arthrography. In most cases it is an associated finding of rotator cuff abnormalities and likely to have a similar etiology. When lesions of the anterior rotator cuff are recognized, the biceps tendon should be scrutinized for inflammatory changes.     

SLAP lesions of the glenoid labrum: CT arthrographic and arthroscopic correlation.

Tears in the superior part of the glenoid labrum in the anterior and posterior directions (SLAP, superior labrum anterior, posterior) result from injuries that place excessive stress on the tendon of the long head of the biceps brachii muscle. The intimate relationship of the tendon and the superior glenoid labrum promotes injury to the latter structure. Four types of SLAP lesions are seen at arthroscopy. Images from 17 patients with surgically proved SLAP lesions who had undergone preoperative computed tomographic (CT) arthrography were retrospectively reviewed to evaluate the value of CT arthrography in the detection and accurate depiction of these labral injuries. The authors compared the findings at videotaped arthroscopic surgery with those from CT arthrography and found that abnormalities of the labral-capsular apparatus could be detected with CT arthrography in 16 of the 17 patients. Furthermore, the CT arthrographic criteria developed during this review helped determine the type of tear in 15 of the 17 patients. CT arthrography appears to be useful in the evaluation of patients with suspected SLAP lesions.     

Anterior-inferior labral lesions of recurrent shoulder dislocation evaluated by MR arthrography in an adduction internal rotation (ADIR) position

PURPOSE: To introduce and evaluate the usefulness of the adduction internal rotation (ADIR) position in MR arthrography for discriminating the following subtypes of Bankart lesions: classic Bankart lesions, anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions, and Perthes lesions. MATERIALS AND METHODS: The study group consisted of 25 patients who had been referred for MR arthrography of the shoulder and then underwent arthroscopy due to recurrent episodes of shoulder dislocation. MR arthrography was performed in three different positions: neutral, abduction external rotation (ABER), and ADIR. The authors evaluated the statistical significance of the method's discriminative diagnostic ability for the subtypes of Bankart lesions according to the position changes. RESULTS: Twenty-three patients had the following single or complex labral lesions: classic Bankart (N = 8), ALPSA (N = 3), complex classic Bankart/ALPSA (N = 8), and complex ALPSA/Perthes (N = 4). Two patients had no visible anteroinferior labral lesions. The performance of ADIR positioning for differentiating ALPSA lesions was superior to the neutral or ABER positioning. The difference of the discriminative lesion detection ability was statistically significant (P <.01) only for detecting ALPSA lesions in the ADIR position. CONCLUSION: MR arthrography in the ADIR position provides high accuracy for the diagnosis of ALPSA lesions, and complements routine MR arthrography when used to diagnose labroligamentous lesions in patients with recurrent shoulder dislocations.