肩袖的解剖学特点

肩袖（shoulder cuff）,又称肌腱袖（myotendiou cuff）或称旋转袖（rotator cuff）,是由起于肩胛骨止于肱骨上端的冈上肌、冈下肌、小圆肌和肩胛下肌的肌腱构成,上述4块肌的肌腱经过肩关节的上、后和前方时与肩关节囊愈着,并互相连接形成一近似环形的腱板围绕肩关节,对肩关节的稳定起重要的作用。肩部的创伤常导致肌腱袖的撕裂,老年人肌腱袖可退行性变常发生撕裂。熟悉肌腱袖的形态结构特点,是肌腱袖损伤诊断与治疗的基础。     

肩袖损伤

肩袖损伤孙常太，黄公怡肩袖是由起于肩肿骨，附着于肱骨头周围的岗上肌、岗下肌、肩胛下肌和小圆肌组成的一组具有相似功能的肌群。四块肌肉的肌腱部分在肪骨头解剖颈处形成袖套状结构，肩袖在肩关节运动中起支持和稳定肩肱关节的作用。当肩关节外展上举时，肩袖肌肉的收...     

肩袖损伤的早期诊断和治疗

肩袖是由冈上肌、冈下肌、小圆肌及肩胛下肌的肌腱构成的包裹肱骨头的袖套样结构,是维持肩关节稳定的主要解剖构造,在肩关节病变中肩袖损伤约占肩关节病变的17%~41%[1]。我们从1996年3月至今共收治肩袖损伤46例,获得满意的诊断治疗效果,现报告如下。1临床资料1.1一般资料本组46     

肩袖损伤修复的生物治疗现状及进展

肩袖是冈上肌、冈下肌、小圆肌和肩胛下肌四块肌肉及其肌腱组成的复合体.它们环绕肱骨头上端,共同协调肩关节运动.在年龄、创伤、劳损等外在因素以及肌腱退变、血运不足、肩峰下撞击等内在因素作用下,肩袖易发生损伤,尤其是肌腱撕裂,进而引发肩部疼痛、力量减弱、活动范围减少.肩袖撕裂通常需手术修复,术后大部分疼痛减轻,肩关节功能改善...     

肩胛下肌腱撕裂的分型和治疗

肩胛下肌是肩袖肌群中最大、最强壮的肌肉,位于肩胛骨前面,呈三角形。起自肩胛下窝,肌束向上经肩胛关节的前方,止于肱骨小结节。而肩袖撕裂主要分3类,第一类:冈上肌腱损伤为主,约占69.3%;第二类:前上肩袖损伤为主(冈上肌腱、肩胛下肌腱);第三类:后上肩袖损伤为主(冈上肌腱、冈下肌腱)。前上肩袖或后上肩袖撕裂的患者功能较差、肩关节力有平衡丧失、肱骨头稳定性差。自2011年至2013年821例肩关节损伤的患者中,51%的患者存在肩胛下肌腱的损伤,其中80%的撕裂小于长轴的1/3,20%的患者是大的撕裂。并在解剖研究中发现,在第一个关节面的撕裂占全部损伤的34%。肩胛下肌腱撕裂分为5个类型:Ⅰ型:磨损或纵向撕裂,可合并CIST(隐藏的肩胛下肌腱撕裂);Ⅱ型:分为2个亚型,ⅡA型第一关节面的撕裂范围50%,可合并CIST,ⅡB型第一关节面的撕裂范围50%;Ⅲ型:第一关节面完全撕裂;Ⅳ型:撕裂面积超过第一关节面;Ⅴ型:完全撕裂(包括肌肉)。CIST患者一般会出现肩关节前方疼痛,应与肌腱炎区分,且一般长头肌腱损伤合并CIST。根据分型可确定治疗方案,Ⅰ型一般不需要修复,ⅡA型需要根据病情严重程度判断,ⅡB型是否需要修复尚存争议,Ⅲ型与Ⅳ型一般需要进行修复,Ⅴ型发病率较少,需要权衡修复利弊。且急性撕裂和慢性损伤的急性撕裂均需要早期修复。镜下修复需要注意锚钉的固定位置,第一、二关节面均可,且要注意肌腱的缝合,肩胛下肌腱撕裂后向内下方回缩,复位时应向外、向上牵拉。而较大的撕裂也可考虑做切开修复。如今肩胛下肌腱损伤越来越多,需不断提高诊断的准确性,改善修复技术。     

MRI影像肩袖损伤与肱骨头囊变的相关研究

[目的]基于核磁共振成像(MRI)的影像学检查结果,探讨并分析肩袖损伤与肱骨头囊变的相关性。[方法] 2017年10月～2019年4月行肩关节MRI扫描并报告肩袖损伤的MRI患者200例纳入本研究,采用PACS系统测量损伤的具体肌肉、损伤深度、损伤长度、止点到损伤点的距离,是否伴随肱骨头囊变及肱骨头囊变面积。[结果] 200例患者中,冈上肌腱损伤191例(95.50%),冈下肌腱损伤5例(2.50%),肩胛下肌腱损伤2例(1.00%),小圆肌腱损伤2例(1.00%)。肩袖损伤同时伴有肱骨头囊变45例(22.50%),均为冈上肌腱损伤。各肩袖肌腱的损伤深度和其止点到损伤点距离的差异无统计学意义(P0.05),但是4块肌肉损伤长度显著不同,冈下肌腱的损伤长度显著大于冈上肌腱、肩胛下肌和小圆肌腱,差异具有统计学意义(P0.05)。45例肱骨头囊变患者,囊变面积与肌腱损伤深度和止点到损伤点的距离无相关(P0.05);但与肌腱损伤长度呈显著正相关(P0.05)。[结论]肱骨头囊变主要见于冈上肌腱损伤,冈上肌腱损伤长度与肱骨头囊变面积呈正相关。     

带线锚钉固定技术修复肩袖损伤生物力学研究

在肩袖肌肉中,冈上肌起着外展肩关节的作用。Inoue等[1]进行有限元分析,证实了冈上肌在肩关节运动起着重要的作用。但冈上肌也是肩袖中容易损伤撕裂的肌肉之一,双排带线锚钉固定修复法因其能增加冈上肌与肱骨头的接触面积,能降低肌肉再次损伤的风险而受到临床的亲睐,但有关该方法的生物力学分析还比较少。本研究分别建立可用于有限元分析的单/双排带线锚钉固定修复肩袖损伤的肩关节模型,比较两种方法修复后肩关节外展状态下冈上肌的应力变化,从生物力学的角度探讨双排带线锚钉固定法的优越性。     

肩胛骨骨折的手术治疗

肩胛骨为近似三角形的不规则扁骨,位于胸廓上方两侧偏后,在肩关节活动中起重要作用.首先它为上肢活动提供肌肉止点,如前方的肩胛下肌、后方的冈上肌、冈下肌和小圆肌,均起自肩胛骨,共同组成肩袖,是维持肩关节动态稳定、完成肩关节活动的最重要结构;其次,肩胛骨在斜方肌、大小菱形肌、背阔肌以及前锯肌等共同作用下,经过肩胛胸壁关节,完成肩胛骨的前伸、回缩以及向上旋转和向下旋转的运动;在肩关节上举过程中,肩胛盂关节面同时向上方旋转,为完成上举活动提供了稳定的平台,协助肩关节完成上举运动(图1)[1].     

肩袖分层损伤诊断与治疗进展

肩袖是由冈上肌、冈下肌、肩胛下肌及小圆肌包绕肱骨头组成的套袖样结构,其中冈上肌最为重要,也是最易受损的结构。高龄以及运动方式的问题往往会造成肩袖的退变及损伤,这也是成人肩关节疼痛的主要原因之一,其中肩袖分层损伤是肩袖损伤的一种常见类型,该损伤有多种治疗方式,但最佳方式并未有统一定论。本文就肩关节分层损伤的发病特点、病因、诊断及治疗等方面进行综述。     

肩袖部分撕裂的关节镜治疗

目的评估应用肩关节镜下冈上肌肌腱肱骨大结节止点重建术治疗EllmanⅢ级肩袖部分撕裂的临床疗效。方法本组15例(15侧),术前MRI提示肩袖损伤,术中关节镜均证实肩袖部分撕裂超过6 mm,其中关节侧9例(右肩6例,左肩3例),滑囊侧6例(右肩4例,左肩2例),全部滑囊侧及6例关节侧肩袖撕裂合并肩峰撞击征。全部病例均行关节镜下肩袖清创、带线锚钉冈上肌肌腱肱骨大结节止点重建,撞击征阳性病例同时行肩峰成形术。结果平均随访30个月(20～44个月),应用JOA评分标准进行肩关节功能评价,术前平均61.3分,术后94.5分(P0.01)。JOA评价体系中疼痛、功能、活动范围及肩关节提升部分明显优于术前,而外展力量、外旋及内旋部分评分则改善不明显。随访期末按JOA评价标准:优12例,良2例,可1例,术前存在肩峰撞击征的12例,末次随访评价撞击试验阴性。结论关节镜下冈上肌肌腱肱骨大结节止点重建术是治疗EllmanⅢ级肩袖部分撕裂的有效方法。     

Analysis of the scapulohumeral rhythm

The movement of the shoulder complex was once aptly described by Codman as the "scapulohumeral rhythm". To demonstrate this rhythm, 20 normal men and four patients with rotator cuff rupture were asked to elevate their arms smoothly in approximately three seconds and five seconds in front of a fluoroscope with or without load. The X-ray was irradiated perpendicularly in the scapular plane. The movements were calculated using a computer. In the normal men, the ratio of the scapular movements to humeral movements was not constant during scapular abduction. The movements of the instant center of the humerus occurred in a small area during abduction, and the result suggested that the movement of the glenohumeral joint was almost rotational. The movements of the instant center of the scapula occurred in a relatively large area during abduction. The movements of the shoulder complex with cuff rupture were quite different from those of normal men.     

Influence of humeral prosthesis height on biomechanics of glenohumeral abduction. An in vitro study

BACKGROUND: During shoulder replacement surgery, the normal height of the proximal part of the humerus relative to the tuberosities frequently is not restored because of differences in prosthetic geometry or problems with surgical technique. The purpose of the present study was to determine the effect of humeral prosthesis height on range of motion and on the moment arms of the rotator cuff muscles during glenohumeral abduction. METHODS: Tendon excursions and abduction angles were recorded simultaneously in six cadaveric specimens during passive glenohumeral abduction in the scapular plane. Moment arms were calculated for each muscle by computing the slope of the tendon excursion-versus-glenohumeral abduction angle relationship. The experiments were carried out with the intact joint and after replacement of the humeral head with a prosthesis that was inserted in an anatomically correct position as well as 5 and 10 mm too high. RESULTS: Insertion of the prosthesis in positions that were 5 and 10 mm too high resulted in significant and marked reductions of the maximum abduction angle of 10 degrees (range, 5 degrees to 18 degrees ) and 16 degrees (range, 12 degrees to 20 degrees ), respectively. In addition, the moment arms of the infraspinatus and subscapularis decreased by 4 to 10 mm. This corresponded to a 20% to 50% decrease of the abduction moment arms of the infraspinatus and an approximately 50% to 100% decrease of the abduction moment arms of the subscapularis, depending on the abduction angle and the part of the muscle being considered. CONCLUSIONS: If a humeral head prosthesis is placed too high relative to the tuberosities, shoulder function is impaired by two potential mechanisms: (1) the inferior capsule becomes tight at lower abduction angles and limits abduction, and (2) the center of rotation is displaced upward in relation to the line of action of the rotator cuff muscles, resulting in smaller moment arms and decreased abduction moments of the respective muscles. Clinical Relevance: In patients managed with shoulder replacement surgery, limitation of range of motion, loss of abduction strength, and overload with long-term failure of the supraspinatus tendon are potential consequences of positioning the humeral head of the prosthesis proximal to the anatomic position.     

The effect of rotator cuff tears on reaction forces at the glenohumeral joint.

The rotator cuff muscles maintain glenohumeral stability by compressing the humeral head into the glenoid. Disruption of the rotator cuff compromises concavity compression and can directly affect the loads on the glenohumeral joint. The purpose of this study was to quantify the effect of rotator cuff tears on the magnitude and direction of glenohumeral joint reaction forces during active shoulder abduction in the scapular plane using nine cadaveric upper extremities. Motion of the full upper extremity was simulated using a dynamic shoulder testing apparatus. Glenohumeral joint reaction forces were measured by a universal force-moment sensor. Five conditions of rotator cuff tears were tested: Intact, Incomplete Supraspinatus Tear, Complete Supraspinatus Tear, Supraspinatus/Infraspinatus Tear, and Global Tear. Reaction forces at the glenohumeral joint were found to steadily increase throughout abduction and peaked at maximum abduction for all conditions tested. There were no significant differences in reaction force magnitude for the intact condition (337 +/- 88 N) or those involving an isolated incomplete tear (296 +/- 83 N) or complete tear (300 +/- 85 N) of the supraspinatus tendon. Extension of tears beyond the supraspinatus tendon into the anterior and posterior aspect of the rotator cuff led to a significant decrease in the magnitude of joint reaction force (126 +/- 31 N). Similarly, such tears resulted in a significant change in the direction of the reaction force at the glenohumeral joint. These results suggest that joint reaction forces are significantly affected by the integrity of the rotator cuff, specifically, by the transverse force couple formed by the anterior and posterior aspects of the cuff. The quantitative data obtained in this study on the effect of rotator cuff tears on magnitude and direction of the reaction force at the glenohumeral joint helps clarify the relationship between joint motion, joint compression and stability.     

Variation in external rotation moment arms among subregions of supraspinatus, infraspinatus, and teres minor muscles.

A rotator cuff tear causes morphologic changes in rotator cuff muscles and tendons and reduced shoulder strength. The mechanisms by which these changes affect joint strength are not understood. This study's purpose was to empirically determine rotation moment arms for subregions of supraspinatus, infraspinatus, and for teres minor, and to test the hypothesis that subregions of the cuff tendons increase their effective moment arms through connections to other subregions. Tendon excursions were measured for full ranges of rotation on 10 independent glenohumeral specimens with the humerus abducted in the scapular plane at 10 and 60 degrees . Supraspinatus and infraspinatus tendons were divided into equal width subregions. Two conditions were tested: tendon divided to the musculotendinous junction, and tendon divided to the insertion on the humerus. Moment arms were determined from tendon excursion via the principle of virtual work. Moment arms for the infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly greater when the tendon was only divided to the musculotendinous junction versus division to the humeral head. Moment arms across subregions of infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly different. A difference in teres minor moment arm was not found for the two cuff tendon conditions. Moment arm differences between muscle subregions and for tendon division conditions have clinical implications. Interaction between cuff regions could explain why some subjects retain strength after a small cuff tear. This finding helps explain why a partial cuff repair may be beneficial when a complete repair is not possible. Data presented here can help differentiate between cuff tear cases that would benefit from cuff repair and cases for which cuff repair might not be as favorable.     

Analysis of the scapulo-humeral rhythm for periarthritis scapulohumeralis

To clarify the scapulo-humeral rhythm in twenty-five patients with periarthritis scapulo-humeralis, the movements of the scapula and the humerus during arm elevation were measured and analysed using a fluoroscope and a computer, and the rhythm of five patient with rotator cuff tear was compared with that of seven normal subjects. The ratio of scapular movement to humeral one in the patients with severe shoulder contracture due to periarthritis scapulohumeralis was greater than that of patients with mild contracture and that of normal subjects. In the patients with rotator cuff tear, wider range of scapular rotation was observed in the early phase of the motion. During the early phase of arm elevation, the humeral head moved to the upper direction by means of gliding in the patients with severely contracted shoulder and rotator cuff tear, and in the patients with mildly contracted shoulder the humeral head moved to the upper direction by means of ball rolling. In the normal subjects no such upward movement of the humeral head was observed. We believe that the restriction of the glenohumeral joint motion and dysfunction of the rotator cuff, which were caused by periarthritis scapulohumeralis, may break down the scapulohumeral rhythm.     

Scapular inclination and inferior stability of the shoulder

Eleven fresh-frozen cadaver shoulders were studied to examine the influence of scapular inclination on inferior stability of the glenohumeral joint. All muscles except the rotator cuff were removed, and the capsule was vented. Inferior stability tests in the hanging position (sulcus test) and in 90° abduction (abduction inferior stability [ABIS] test) were simulated by the application of a 1.5 kg load with the scapula inclined at - 15°, 0°, 15°, and 30° in the sulcus test and at 15°, 30°, 45°, and 60° in the ABIS test. An electromagnetic tracking device was used to record the position of the humerus in relation to the glenoid. In the sulcus test all of the shoulders dislocated when the scapula was inclined at - 15°. However, when the scapula was inclined at 30°, no shoulder dislocated before loading, and one shoulder dislocated after loading. As a result both the loaded and unloaded positions of the humeral head shifted significantly to the superior direction as the scapular inclination increased (p < 0.0001). In the ABIS test, however, the positions of the humeral head shifted interiorly with an increase in scapular inclination (p < 0.0001), although none of the shoulders dislocated in any of the inclination angles. We conclude that scapular inclination contributes significantly to inferior stability of the glenohumeral joint. Increased scapular inclination prevents inferior displacement of the humeral head, probably because of a bony cam effect that causes tightening of the superior capsule.     

Experimental investigation of reaction forces at the glenohumeral joint during active abduction

Reaction forces at the glenohumeral joint counterbalance the mass moment of the upper extremity during shoulder motion and are directly related to the activity of muscles across the joint. Because stability of the glenohumeral joint depends on compression of the humeral head into the glenoid, reaction forces constitute an important aspect of shoulder biomechanics. The objective of this study was to measure reaction forces at the glenohumeral joint during active scapula plane abduction. Furthermore, to clarify the relationship between the deltoid and supraspinatus muscles throughout abduction, this study investigated the effect of 4 variations of applied muscle forces on the magnitude and direction of glenohumeral reaction forces. We used a dynamic shoulder testing apparatus equipped with a force-moment sensor to directly measure reaction forces. Joint reaction forces increased throughout abduction and peaked at approximately 90 degrees for all testing conditions. The largest reaction forces occurred when the ratio of applied forces favored the supraspinatus tendon, whereas simulated paralysis of the supraspinatus resulted in a significant decrease in joint compression. There were no differences in direction of the reaction force between testing conditions. The results of this study indicate that the magnitude of glenohumeral joint reaction forces varies according to the ratio of forces between the supraspinatus and deltoid muscles. Thus, conditions characterized by either deltoid or supraspinatus dysfunction may result in abnormal loading mechanics at the glenohumeral joint. Understanding the relationship between rotator cuff function and glenohumeral reaction forces will aid in clarifying the importance of muscular activity to shoulder stability and strength as it relates to compression of the humeral head.     

Shoulder impingement

Understanding the pathophysiology and treatment of rotator cuff disorders is the key to understanding all other aspects of shoulder rehabilitation. Impingement rehabilitation focuses on strengthening the humeral head depressors, while ignoring the deltoid and supraspinatus muscles. Later treatment includes specific retraining of scapular balancing muscles. The final phase of treatment includes strengthening the prime humeral movers in positions that avoid further stress to the injured rotator cuff tendons and, last of all, specifically strengthening the supraspinatus muscle.     

The effect of infraspinatus disruption on glenohumeral torque and superior migration of the humeral head: a biomechanical study

Rotator cuff ruptures that extend into the infraspinatus tendon may cause dysfunction and superior migration of the humerus. The purpose of this study was to determine whether a threshold size of infraspinatus defect exists beyond which abduction torque generation decreases and superior migration of the humeral head increases. Glenohumeral abduction torque and superior humeral head translations were measured in hanging arms in neutral rotation in cadaver shoulders (n = 10). Loads were applied to the rotator cuff tendons and the middle deltoid. After sequential detachment of the infraspinatus, abduction torque progressively decreased. At three-fifths detachment, abduction torque was significantly lower than after supraspinatus release alone (52% vs 61%, P <.05). Superior translation after complete supraspinatus and infraspinatus detachment increased significantly (P <.05), but no intermediate threshold was detected. Therefore, the entire infraspinatus contributes to abduction torque generation and stabilizes the humeral head against superior subluxation. Even with a tear extending into the superior infraspinatus, the infraspinatus contributes abduction force generation across the glenohumeral joint.     

Mechanical environment of the supraspinatus tendon: three-dimensional finite element model analysis

BACKGROUND: We analyzed the mechanical environment of the supraspinatus tendon using a three-dimensional finite element model with the software programs MENTAT and MARC. METHODS: The supraspinatus tendon that attaches to the superior facet was extracted and modeled. The geometric shape of the humeral head was determined from computed tomography images, and the shape of the supraspinatus tendon was determined from magnetic resonance images of the shoulder at 0 degrees of abduction in a healthy 27-year-old man. The distal portion of the humeral head was fixed, and 10 N of tensile force was applied to the proximal end of the tendon. The tensile stress was calculated. RESULTS: The tensile stress was 1.8 MPa for the bursal side and 15.0 MPa for the articular side of the anterior portion of the supraspinatus tendon. The intensity was 0 MPa for the bursal side and 4.5 MPa for the articular side of the middle portion of the tendon. The intensity was 0.1 MPa for the bursal side and 5.2 MPa for the posterior edge of the tendon. CONCLUSIONS: Based on the three-dimensional finite element method, the maximal tensile stress was observed on the articular side of the anterior edge of the supraspinatus tendon. Our result may explain the frequent occurrence of rotator cuff tears at this site.