Arthroscopic management of subscapularis tears

Tears of the subscapularis were previously believed to be rare, but are now recognized to be very common. As maintenance of the subscapularis footprint is integral to normal biomechanical function of the shoulder it is important for the shoulder surgeon to be adept at recognizing and treating these tears. A combination of physical examination tests can be used to determine both the presence and size of a subscapularis tear. Compared with posterosuperior rotator cuff tears, magnetic resonance imaging detection of subscapularis is less reliable and therefore requires a high index of suspicion. Arthroscopic repair of the subscapularis presents unique challenges but can be safely and successfully performed with careful attention to detail. The results of arthroscopic subscapularis repair are encouraging at intermediate follow-up and comparable with or better than that reported with open repair.     

Biomechanical evaluation of a single-row versus double-row repair for complete subscapularis tears

The purpose of the study was to compare a single-row repair and a double-row repair technique for the specific characteristics of a complete subscapularis lesion. Ten pairs of human cadaveric shoulder human shoulder specimens were tested for stiffness and ultimate tensile strength of the intact tendons in a load to failure protocol. After a complete subscapularis tear was provoked, the specimens were assigned to two treatment groups: single-row repair (1) and a double-row repair using a “suture bridge” technique (2). After repair cyclic loading a subsequent load to failure protocol was performed to determine the ultimate tensile load, the stiffness and the elongation behaviour of the reconstructions. The intact subscapularis tendons had a mean stiffness of 115 N/mm and a mean ultimate load of 720 N. The predominant failure mode of the intact tendons was a tear at the humeral insertion site (65%). The double-row technique restored 48% of the ultimate load of the intact tendons (332 N), while the single-row technique revealed a significantly lower ultimate load of 244 N (P = 0.001). In terms of the stiffness, the double-row technique showed a mean stiffness of 81 N/mm which is significantly higher compared to the stiffness of the single-row repairs of 55 N/mm (P = 0.001). The double-row technique has been shown to be stronger and stiffer when compared to a conventional single-row repair. Therefore, this technique is recommended from a biomechanical point of view irrespectively if performed by an open or arthroscopic approach.     

Repair of tears of the subscapularis tendon

Tears of the subscapularis are much less common than tears of the supraspinatus and infraspinatus. Subscapularislesions are usually traumatic in etiology and occur in younger patients. These lesions can be complete or limited to the superior insertion of the subscapularis, and they may be isolated or occur with other rotator cuff lesions. In most instances, treatment of subscapularis tears is surgical. In this article, we present the clinical and radiographic findings, discuss operative indications, and illustrate our preferred surgical technique for tears of the subscapularis tendon.     

Isolated and combined tears of the subscapularis tendon

BACKGROUND: Isolated and combined subscapularis tendon tears are rare and are described in the literature only in small numbers. HYPOTHESIS: The outcome of surgical intervention for isolated and combined subscapularis tendon tears may be influenced by the tear pattern of the anterior rotator cuff and the period of time between trauma and surgical procedure. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between 1994 and 1999, 34 shoulders with isolated traumatic tears (16 shoulders) or subscapularis tendon rupture combined with a supraspinatus tendon tear were treated operatively. The average patient age was 51 years, and the mean follow-up period was 37 months. For statistical analyses, the Friedman and Mann-Whitney tests were used. RESULTS: In patients with isolated tears, the Constant score rose from an average of 43.9 to 88.7 points (P < .01), and in patients with combined tears, it rose from an average of 40.6 to 74.7 points (P <.01). Isolated tears improved 14 points more than combined tears (P <.05). The delay between trauma and surgical intervention was inversely proportional to the improvement in the Constant score. The Spearman coefficient of correlation was -0.97 in isolated tears and -0.89 in combined tears. CONCLUSIONS: Young patients with isolated traumatic tears of the subscapularis tendon and immediate repair have the best prognostic factors for treatment. Accuracy in the trauma history and the clinical and radiographic examination is demanded.     

Sensitivity of MR arthrography in the evaluation of acetabular labral tears

OBJECTIVE: MRI has historically provided suboptimal visualization of tears of the acetabular labrum. Degenerative fraying and underlying cartilage abnormalities can often mimic tears of the labrum on conventional MRI. Administration of intraarticular gadolinium enhances the MRI appearance of the labrum to improve detection of labral abnormalities. This study examined the improved diagnostic sensitivity of MR arthrography compared with conventional MRI and the importance of confining the study to a small field of view. MATERIALS AND METHODS: Fifty-one hips were imaged in 48 patients. Fourteen hips underwent conventional MRI with a large field of view (30-38 cm). Seven hips underwent conventional MRI with a small field of view (14-20 cm). Thirty hips underwent MR arthrography with a small field of view (14-20 cm). Labral tears were diagnosed when contrast material was identified within the labrum or between the labrum and the acetabulum, when a displaced fragment was noted, or when a paralabral cyst was identified. All study results were compared with findings at the time of hip arthroscopy. RESULTS: Conventional MRI with a large field of view was 8% sensitive in detecting labral tears compared with findings at the time of arthroscopy. Diagnostic sensitivity was improved to 25% with a small field of view. MR arthrography with a small field of view was 92% sensitive in detecting labral tears. CONCLUSION: A combination of MR arthrography and a small field of view is more sensitive in detecting labral abnormalities than is conventional MRI with either a large or a small field of view.     

MR evaluation of factors predicting the development of rotator cuff tears

PURPOSE: The purpose of this work was to assess the incidence of various factors predicting impingement in the shoulder. METHOD: MR examination was used to assess various anatomic parameters in 46 patients with clinical abnormalities of the shoulder and 40 asymptomatic volunteers. All patients had undergone surgery, showing no rotator cuff tear. RESULTS: A few of the parameters evaluated were significantly different in the two groups: The acromion was more frequently curved or hook-shaped in patients than in volunteers. The acromiohumeral distances differed (4.87 mm in patients and 6.05 mm in volunteers); so did the coracohumeral distances (7.9 mm in patients and 8.9 mm in volunteers). The shape of the acromioclavicular joint and the anterior covering of the humerus, defined on the coronal view, also differed (1.07 mm in patients and 1.49 mm in volunteers). Only the shapes of the acromioclavicular joint and of the acromion were linked with age. CONCLUSION: All these factors reflected a decrease in the acromiohumeral space, except for the anterior covering of the acromial arch, which could be due to anterior instability.     

Relationship between subscapularis tears and injuries to the biceps pulley

Purpose

The purpose of this study was to analyse the relationship between long head of the biceps brachii (LHBT) lesions and subscapularis tears. The hypothesis was that a bicipital pulley might remain intact, even in the case of a subscapularis tear.

Methods

Between 2010 and 2011, all patients who had a primary arthroscopic repair of a subscapularis tear were potentially included in this prospective study. The outcome of interest was the prevalence and type of arthroscopic lesions of the LHBT and bicipital pulley. Furthermore, the supposed pathomechanics of injury and the treatment proposed (conservative, pulley repair, tenodesis, tenotomy, etc.) was recorded. The following baseline characteristics were assessed: age, sex, shoulder side, and limb dominance.

Results

Of the 218 patients, the superior glenohumeral ligament/coracohumeral ligament (SGHL/CHL) complex was normal in 54 patients (25%), stretched in 84 patients (39%), and absent in 77 patients (35%). Below the SGHL/CHL complex in the bicipital groove, the medial wall of the LHBT sheath was normal in 25%, partially torn in 39%, and completely torn in 35%. In 25 of the 218 patients (11%), a pathologic LHBT with an intact SGHL/CHL complex was observed. In these cases, the medial wall of the bicipital sheath was torn in 92%.

Conclusions

The biceps pulley system, including the SGHL/CHL complex and subscapularis tendon, merits recognition as an important anatomical structure, and its lesions contribute to shoulder pathology. The subscapularis tendon is very important for the stability of the LHBT and should be included in the pulley system. In cases of a tear associated with a lesion of the SGHL/CHL complex, the LHBT is nearly always unstable and pathologic.

Level of evidence

II.

     

膝关节前交叉韧带撕裂MRI多征象分析

前交叉韧带（anterior cruciate ligament,ACL）起自股骨外侧髁内侧面的后部,由外上向内下旋转走行,止于胫骨髁间棘略前外侧。ACL的作用主要防止胫骨向前移位和内旋,并限制膝关节过伸和股骨内旋,是维持膝关节稳定的主要结构之一。ACL撕裂是膝关节创伤常见的并发症,MRI能直接显示撕裂的ACL,并能显示关节其他结构的继发改变,是检查ACL撕裂准确和有效的非侵蚀性方法。     

Clinical outcome and structural integrity of all-arthroscopic repair of degenerative subscapularis tendon tears

Purpose

The purpose of this study was to evaluate the clinical outcome of all-arthroscopic repair of degenerative subscapularis tendon tears and post-operative structural integrity using magnetic resonance imaging with a short-term follow-up.

Methods

Twenty-one patients were treated all-arthroscopically for a full-thickness degenerative subscapularis tendon tear. Median patient age was 55 years (range, 41–69). Median follow-up was 25 months (range, 15–44). Patients were evaluated prior to surgery and at follow-up: active range of motion, VAS pain, Simple Shoulder Test (SST), and the Disabilities of the Arm, Shoulder, and Hand score (DASH). At final follow-up, the Constant–Murley score was evaluated.

Results

Mean active range of motion showed significant post-operative improvement (p < 0.001). VAS pain improved from 8.3 (SD ± 1.3) pre-operatively to 2.7 (SD ± 1.8) post-operatively (<0.001); SST increased from 20 % (SD ± 26) pre-operatively to 83 % (SD ± 27) post-operatively (<0.001); DASH scores improved 67 (SD ± 19) to 18 (SD ± 21) post-operatively (<0.001). Post-operative Constant–Murley score was 79 (SD ± 12). Two patients had failure of the repair on post-operative MRI. Twelve cases (57 %) showed post-operative progression of fatty muscle infiltration.

Conclusion

All-arthroscopic repair is an effective treatment modality for degenerative subscapularis tendon tears with an anterosuperior tear pattern with good clinical results and high patient satisfaction. Although there was a high tendon-to-bone healing rate, fatty muscle infiltration was progressive in more than half of the patients.

Level of evidence

Therapeutic case series, Level IV.     

Diagnosis of recurrent meniscal tears: prospective evaluation of conventional MR imaging, indirect MR arthrography, and direct MR arthrography

PURPOSE: To prospectively investigate the accuracy of conventional magnetic resonance (MR) imaging, direct MR arthrography, and indirect MR arthrography in assessment of possible recurrent or residual meniscal tears. MATERIALS AND METHODS: Three hundred sixty-four patients who had previously undergone meniscal preservation surgery were prospectively examined with conventional MR imaging, indirect MR arthrography, and direct MR arthrography. Ninety-four patients (104 postoperative menisci) underwent subsequent second-look arthroscopic surgery. Each case was evaluated for (a) surfacing intrameniscal intermediate- or T1-weighted signal intensity, (b) surfacing intrameniscal T2-weighted signal intensity, (c) morphologic changes beyond those expected postoperatively, (d) joint effusion on conventional MR or indirect MR arthrographic studies, and (e) overall presence or absence of recurrent meniscal tear. RESULTS: Seventy-one arthroscopically proved recurrent meniscal tears were found. In the diagnosis of recurrent meniscal tears, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 86%, 67%, 83%, 71%, and 80%, respectively, for conventional MR imaging; 83%, 78%, 90%, 64%, and 81%, respectively, for indirect MR arthrography; and 90%, 78%, 90%, 78%, and 85%, respectively, for direct MR arthrography. No significant difference in the diagnostic accuracy of one method relative to another was observed (P >.54). Surfacing intrameniscal T2-weighted signal intensity was the most specific sign, with the highest positive predictive value of a recurrent tear. CONCLUSION: Although a small incremental increase in accuracy is associated with the use of direct MR arthrography over conventional MR imaging and indirect MR arthrography, no significant difference in diagnostic accuracy among the three techniques was demonstrated for detection of recurrent or residual meniscal tear.     

肩关节MR造影三维VIBE序列对肩袖撕裂的评价

目的 对比评价肩关节MR造影三维 VIBE和常规二维TSE T1W序列对肩袖撕裂的诊断价值.方法 由2名影像诊断医师独立回顾对比分析99例肩关节造影三维 VIBE重建图像和常规二维TSE T1W序列图像,判定有无肩袖撕裂,分别计算其敏感性和特异性.采用McNemar检验评价2种方法诊断价值是否存在统计学差异.结果 99例患者中,肩关节镜证实肩袖撕裂为35例,其中全层撕裂为13例,部分撕裂为22例(关节侧撕裂8例,滑囊侧撕裂9例,腱内撕裂5例).三维 VIBE与常规二维TSE T1W序列对肩袖全层撕裂和关节侧撕裂均准确诊断.三维 VIBE对肩袖撕裂的敏感性和特异性分别为62.86%和96.88%(医师甲),60.00%和98.44%(医师乙);常规二维TSE T1W序列对肩袖撕裂的敏感性和特异性分别为60.00%和96.88%(医师甲),65.71%和96.88%(医师乙).三维 VIBE与常规二维TSE T1W序列的诊断性能无统计学差异.结论 肩关节MR造影三维 VIBE序列可以替代常规二维TSE T1W序列评价肩袖撕裂.     

Noninvasive evaluation of knee meniscal tears: preliminary comparison of MR imaging and CT

One hundred twenty knees were examined prospectively with both axial computed tomography (CT) and magnetic resonance (MR) imaging to compare the value of these techniques in patients with clinical evidence of meniscal tears. Sixty-four of these knees were subsequently evaluated with diagnostic arthroscopy. In this group, CT was superior to MR imaging for meniscus evaluation in 29.7% of the knees, equal to MR in 54.7%, and inferior to MR in 15.6%. Although surface-coil MR imaging shows great promise and has numerous advantages over more conventional techniques, this preliminary experience suggests that, at least with certain imaging equipment and techniques, CT may be slightly more efficacious than 0.5-T MR imaging in meniscus evaluation. However, further comparative studies at higher field strengths are needed before the relative roles of CT and MR imaging can be established.     

3.0T常规MRI与MR髋关节造影诊断髋臼唇撕裂的对比研究

目的 在3.0 T场强中,比较常规髋关节MRI及MR髋关节造影对髋臼唇撕裂的诊断价值.方法 回顾分析44例髋关节病变患者的患侧髋关节常规MRI及MR髋关节造影资料,将每例患者的臼唇划分为前、上、后3处区域(共计132处),确定有无撕裂,并进行分型.其中5例患者经髋关节镜检查.对于常规MRI及MR髋关节造影获得的臼唇撕裂及分型数据差异比较采用Wilcoxon秩和检验,一致性比较采用Kappa检验.结果 常规MRI与MR髋关节造影诊断完全相同者计116处臼唇,只有16处存在诊断差异.其中,前者诊断无撕裂而后者诊断撕裂者9处,前者诊断撕裂但后者诊断无撕裂者6处,其余1处两者均诊断为撕裂但分型不同.常规MRI与MR髋关节造影的评价差异没有统计学意义(Z=0.347,P＞0.05),且具有极好的一致性(K=0.781,P＜0.01).在接受关节镜的5例患者中,常规MRI、MR髋关节造影及关节镜结果均完全吻合.结论 对髋臼唇撕裂,3.0 T常规髋关节MRI可获得与MR髋关节造影基本相同的诊断效果.     

MR imaging of rotator cuff tears]

A total of 115 patients with clinical symptoms and signs suggesting rotator cuff tears underwent MR imaging with a 1.5-Tesla system. The body coil was used as the receiver coil in 24 patients and a single 10 cm surface coil in 91. Arthrography or MR imaging with intra-articular Gd-DTPA (MR arthrography) was performed in 95 of the 115. T2-weighted images with the body coil showed high signal intensity lesions in rotator cuffs in only seven of the 10 patients who had tears demonstrated by arthrography or MR arthrography. On the other hand, T2-weighted images with the surface coil demonstrated high signal intensity lesions in cuffs in all 27 patients who were diagnosed to have tears by arthrography or MR arthrography. In 12 patients, T2-weighted images with the surface coil showed high signal intensity lesions in cuffs, while arthrography and MR arthrography did not show tears. Surgery was performed in four of the 12 patients and partial tears were confirmed. A single 10 cm surface coil, 3 mm slice thickness and 2.5 second repetition time seem to account for the fine visualization of cuff tears by the T2-weighted images. These results suggest that T2-weighted images obtained with the surface coil are superior to arthrography and MR arthrography.