Schultergelenkinstabilität

Shoulder instability is a common clinical feature leading to recurrent pain and limited range of motion within the glenohumeral joint. Instability can be due a single traumatic event, general joint laxity or repeated episodes of microtrauma. Differentiation between traumatic and atraumatic forms of shoulder instability requires careful history and a systemic clinical examination. Shoulder laxity has to be differentiated from true instability followed by the clinical assessment of direction and degree of glenohumeral translation.Conventional radiography and CT are used for the diagnosis of bony lesions. MR imaging and MR arthrography help in the detection of soft tissue affection, especially of the glenoid labrum and the capsuloligamentous complex.The most common lesion involving the labrum is the anterior labral tear, associated with capsuloperiostal stripping (Bankart lesion). A number of variants of the Bankart lesion have been described, such as ALPSA, SLAP or HAGL lesions.The purpose of this review is to highlight different forms of shoulder instability and its associated radiological findings with a focus on MR imaging.     

Humeral avulsions of the glenohumeral ligament: imaging features and a review of the literature

OBJECTIVE: We describe the radiologic findings of the humeral avulsion of the glenohumeral ligament (HAGL lesion) and its commonly associated injuries. MATERIALS AND METHODS: A retrospective review of six cases of HAGL lesion diagnosed at our institution from October 1996 to February 2001 was performed. We reviewed the radiology reports, radiologic examinations, medical records, and operative notes. All patients had undergone radiography, and four patients had undergone MR imaging of the shoulder before diagnostic arthroscopy. RESULTS: All the patients were men who ranged in age from 19 to 41 years (mean, 26 years). Four patients (67%) had an anterior shoulder dislocation. Three of the HAGL lesions (50%) were detected on radiologic examinations, either by radiography or MR imaging. One patient had a bony HAGL. All patients had associated injuries. The most common associated abnormalities were osteochondral injury of the humeral head (n = 3), rotator cuff tear (n = 3), Bankart lesion (n = 3), Hill-Sachs lesion (n = 2), avulsion of the middle glenohumeral ligament (n = 1), partial tear of the biceps brachii tendon (n = 1), and comminuted fracture of the clavicle (n = 1). CONCLUSION: With an incidence of 7.5% and 9.4% in two large series of patients, the HAGL lesion is an important cause of anterior instability of the glenohumeral joint. The majority (68%) of patients with an HAGL lesion have associated injuries.     

盂肱关节前方不稳MR表现与关节镜手术所见比较

 目的 探讨盂肱关节前方不稳的关节镜检查和3.0T MRI表现。方法 收集45例盂肱关节前方不稳患者的MRI检查及关节镜检查资料,回顾性对照分析MRI与多角度镜头关节镜手术结果,总结损伤类型、程度,采用Kappa检验分析MRI与关节镜诊断结果的一致性,观察MRI对各种损伤诊断结果及敏感度。结果 盂唇损伤在盂肱关节前方不稳病变中占84.4%(38/45),其中前下盂唇损伤占 51.1%(23/45),盂唇损伤合并Hill-sachs损伤、关节囊损伤占44.2%(20/45),盂唇损伤合并骨性Bankart损伤占17.7%(8/45)。MRI诊断前下盂唇损伤、HAGL病变、Hill-sachs病变的敏感度分别为78.2%、71.0%、90.0%。MRI与关节镜诊断结果具有一致性,其中诊断肩胛下肌及肌腱损伤及骨性Bankart损伤的结果完全一致,诊断前下盂唇损伤、HAGL病变及Hill-sachs病变的一致性较好,诊断SLAP损伤一致性一般。结论 3.0T MRI能够较准确地显示盂肱关节前方不稳常见病变及MRI征象,为临床早期诊断和治疗提供依据。     

Open bankart reconstruction

Anterior glenohumeral instability is a common disorder often associated with traumatic detachment of theanteroinferior capsulolabral complex (Bankart lesion). Surgical treatment is often required to prevent recurrent instability. Open Bankart reconstruction has proven to be a reliable procedure with low recurrence rates. The open surgical approach allows treatment of all patterns of anterior instability and does not require the presence of a discrete Bankart lesion. Successful reconstruction requires reattachment of the capsulolabral complex as well as reduction of capsular redundancy if present. Excessive tightening of the capsule should be avoided. The techniques for open repair have been well established and should be easily reproducible by most surgeons.     

The Bankart lesion of the shoulder: A biomechanical analysis following repair

The Bankart lesion of the shoulder has long been associated with anterior instability. Our laboratory has developed a biomechanical model of the human shoulder which was used to determine the effects of creating a Bankart lesion on cadaveric specimens and then to compare the effects of two repair techniques. The model simulates the abducted, externally rotated position of the glenohumeral joint and uses pneumatic cylinders to simulate the rotator cuff forces. Specimens were tested intact following a partial Bankart lesion, following a complete Bankart lesion, and after performing a Bankart repair using three Mitek suture anchors. Finally, both the traditional and Mitek repairs were tested until failure. Strain in the inferior glenohumeral ligament (IGHL) and torque resistance was measured as an indication of instability of the joint. Strain was noted to decrease with increasing depth of lesion of the IGHL. Torsional rigidity of the shoulder decreased with increasing depth of lesion as well. Repairing the shoulder restores the strain and rigidity to control conditions. The mean load until failure was greater with the traditional repair than with the suture anchor technique. This study quantitates the effects of a Bankart lesion of the shoulder, and demonstrates that repairing the lesion with a suture anchor technique restores the biomechanics of the shoulder.Investigation performed at the Albert B. Ferguson, Jr., MD Laboratory for Orthopaedic Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USAThis work was supported by a grant from the Whitaker Foundation     

Magnetic resonance evaluation of the labral capsular ligamentous complex: a pictorial review

Magnetic resonance imaging of the shoulder is a common imaging test, and in the course of routine evaluation it can provide accurate information regarding the labral capsular ligamentous complex (LCLC). Common patterns of labral injury include fraying, flap tears and labral distraction, which can be readily identified on both coronal and axial planes by paying attention to signal and morphological characteristics. Capsular and ligamentous pathology may be subtle, but is recognizable using a high-resolution technique that has differential contrast between native intra-articular fluid and the adjacent labrum and capsular restraints. Common patterns of capsular injury include a thickened, hyperintense capsule, sometimes with disruption and retraction. The inferior glenohumeral ligament is the primary stabilizer of the shoulder joint, and although failure of this structure is uncommon, the injury is easily identified. Shoulder instability is a common presentation, the diagnosis of which is dependent upon recognizing various injury patterns including Bankart lesions, reverse Bankart lesions, anterior labroligamentous periosteal sleeve avulsion (ALPSA) and failure of the inferior glenohumeral ligament.     

Magnetic resonance imaging of nontraumatic shoulder instability in children

Nontraumatic shoulder instability is infrequent in children. We examined prospectively with high-field magnetic resonance imaging (MRI) 11 patients with this disorder, including 2 with Holt-Oram syndrome and 11 healthy control subjects. The MR findings in the glenohumeral joint in normally growing children are presented. Two patients with shoulder instability were considered as normal, one presented with type 2 (Zlatkin) labral lesions, three, type 3 and one, type 4 lesions. Close attention to the normal imaging patterns of the maturing glenohumeral joint is required to avoid pitfalls in the interpretation of the images.     

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.     

Advanced imaging of glenohumeral instability: the role of MRI and MDCT in providing what clinicians need to know

The inherently unstable anatomy of glenohumeral (GH) joint predisposes it to shoulder dislocation. Shoulder dislocation can occur either due to acute trauma or due to chronic microtraumas in the setting of underlying morphological abnormality. A plain radiograph is the initial imaging modality for diagnosis and management of shoulder dislocation and its associated osseous abnormalities such as Hill-Sachs deformity or osseous Bankart lesion. However, advanced imaging techniques such as multidetector CT (MDCT) with three-dimensional (3D) volume rendering and MRI can be helpful in further characterization of osseous abnormalities and detection of associated soft tissue injuries, respectively. These additional findings may be useful for optimal surgical repair for GH joint stabilization. In this pictorial essay, we present the clinically relevant osseous and soft tissue pathologies in various types of shoulder dislocation, with emphasis on pathologies that can be demonstrated using advanced imaging examinations. Discussed pathologies include glenoid fractures, labral tears, Bankart lesion, Hill-Sachs defect, Perthes lesion, anterior labral posterior sleeve avulsion (ALPSA), glenolabral articular disruption (GLAD), humeral avulsion of the glenohumeral ligament (HAGL), Kim lesion, and other associated soft tissue and nerve injuries.     

MR imaging in sports-related glenohumeral instability

Sports-related shoulder pain and injuries represent a common problem. In this context, glenohumeral instability is currently believed to play a central role either as a recognized or as an unrecognized condition. Shoulder instabilities can roughly be divided into traumatic, atraumatic, and microtraumatic glenohumeral instabilities. In athletes, atraumatic and microtraumatic instabilities can lead to secondary impingement syndromes and chronic damage to intraarticular structures. Magnetic resonance (MR) arthrography is superior to conventional MR imaging in the diagnosis of labro-ligamentous injuries, intrinsic impingement, and SLAP (superior labral anteroposterior) lesions, and thus represents the most informative imaging modality in the overall assessment of glenohumeral instability. This article reviews the imaging criteria for the detection and classification of instability-related injuries in athletes with special emphasis on the influence of MR findings on therapeutic decisions.     

肩关节损伤的MR影像诊断

目的 探讨常规MRI和MR间接关节造影对肩关节损伤的诊断价值.方法 回顾分析经关节镜证实的90例肩关节损伤患者肩关节常规MRI和MR问接关节造影表现,其中肩袖病变组57例、盂肱关节不稳组33例.对常规MRI和MR间接关节造影诊断结果进行Fisher确切概率法比较.结果 (1)肩袖病变组中MR间接关节造影37例,显示部分撕裂10例,1例漏诊;显示完全撕裂17例,2例误诊,7例肩袖无撕裂.MR间接关节造影显示部分撕裂的敏感度、特异度、准确度分别为90.9%(10/11)、92.3%(24/26)、91.9%(34/37);显示完全撕裂的敏感度、特异度、准确度分别为89.5%(17/19)、94.4%(17/18)、91.9%(34/37).MR间接关节造影诊断肩袖部分及完全撕裂的敏感度及准确度均高于常规MRI(P<0.05).(2)盂肱关节不稳组中,盂唇损伤26例,Hill-sachs病变27例、反Hill-sachs病变2例、骨陛Bankart损伤7例、关节囊损伤18例.间接关节造影20例,显示盂唇损伤14例,1例漏诊,5例正常.MR间接关节造影显示盂唇损伤的敏感度、特异度、准确度分别为93.3%(14/15)、100.0%(5/5)、95.0%(19/20).前者诊断盂唇损伤的敏感度及准确度明显高于常规MRI(P<0.05).结论 MR检查特别是MR间接关节造影能够准确显示肩关节常见病变及相关组织的病理发展过程,为临床诊断及治疗提供影像学依据.     

The POLPSA lesion: MR imaging findings with arthroscopic correlation in patients with posterior instability

OBJECTIVE: To evaluate the features of the posterior labrocapsular periosteal sleeve avulsion (POLPSA) lesion on MR imaging in athletes with posterior shoulder instability. DESIGN AND PATIENTS: Six male athletes (age range 19-43 years) with avulsion of the posterior glenoid periosteum were identified on MR imaging. There were four football players, one wrestler, and one competitive weightlifter. The weightlifter had a bilateral condition so that seven shoulders were evaluated. MR imaging was performed with a 1.5 T magnet utilizing conventional and fat-saturated fast spin-echo coronal oblique and sagittal oblique sequences and a 3D-GRE transaxial sequence. Surgical correlation was available in all shoulders. RESULTS: All patients presented with pain and a joint effusion. The size of the periosteal sleeve and redundant joint recess was variable. Fibrous proliferation was noted arthroscopically in four shoulders beneath the sleeve. Although the posterior labrum was detached in all studies, only one labrum had a tear while two showed marked degeneration. CONCLUSION: The POLPSA lesion is an abnormality that can be associated with posterior instability. It differs from a reverse Bankart lesion because the periosteum, although detached, remains intact with the posterior capsule and detached posterior labrum. This lesion may represent an acute form of a Bennett lesion.     

Shoulder instability: evaluation with MR imaging

Instability of the glenohumeral joint is a common cause of chronic shoulder pain and disability. One or more episodes of subluxation or dislocation may result in a tear, detachment, or attenuation of the glenoid labrum, stripping of the joint capsule from the scapula, or trauma to the tendons or muscles of the rotator cuff. A series of 27 shoulders examined with magnetic resonance (MR) imaging showed changes of glenohumeral instability, which were confirmed with open or arthroscopic surgery. MR imaging was capable of displaying common types of pathologic conditions resulting from instability, including labral trauma, capsular detachment, and retraction of the subscapularis muscle. MR imaging is a valuable diagnostic tool for the evaluation of glenohumeral instability.     

Open repairs for the treatment of anterior shoulder instability

Successful treatment of anterior instability of the shoulder requires a balance between restoring joint stability and minimizing loss of glenohumeral motion. The choice of treatment should be individualized on the basis of the patient's occupation and level of participation in sports, as well as on the degree of instability of the shoulder. Despite discussions to the contrary, there is no single "essential lesion," as proposed by Bankart, that is responsible for recurrent anterior shoulder instability, although the Bankart lesion is by far the most important. The choice of operative treatment must be tailored to correct the abnormality that is identified at the time of surgery. A variety of promising arthroscopic techniques have been developed for the treatment of anterior shoulder instability; however, open stabilization remains the standard, especially for severe instabilities, revision procedures, and for athletes who participate in contact sports. This article will review the open surgical techniques used for treatment of anterior instability of the shoulder. Both current and historical operations will be discussed. Regardless of which procedure is chosen by a surgeon, the treatment should follow the guidelines taught by Rowe: anatomic dissection at the time of surgery, identification and repair of the lesions responsible for the instability, returning tissues to their anatomic locations, and early postoperative range of motion. By following these guidelines, the results of treatment of anterior instability of the shoulder can be optimized.     

Stabilizing effect of the transferred conjoined tendon on shoulder stability

The modified Boytchev procedure, i.e., rerouting of the coracoid process with its attached conjoined tendon (short head of biceps and coracobrachialis) deep to the subscapularis and reattachment to its anatomical location, has been advocated for recurrent anterior glenohumeral instability with controversial clinical outcomes. We aimed to investigate the dynamic contribution of the conjoined tendon in situ or transferred to the glenohumeral articulation in stable and unstable shoulders. Eight cadaveric shoulders were tested with the arm in 90° abduction and 90° external rotation. A constant 1.5 kg anterior translation force was applied to the proximal humerus, combined with 0, 1.5, 3.0 kg of load applied to the conjoined tendon sequentially. Anterior displacement of the humeral head relative to the scapula was recorded before and after an imitation Bankart lesion was created, and after treated with the modified Boytchev procedure for the Bankart lesion. Application of load to the conjoined tendon significantly reduced anterior displacement of the humeral head either with the capsule intact or with Bankart lesion simulated. The most significant decrease of the anterior displacement occurred when the conjoined tendon was transferred beneath the subscapularis. Our findings show that the conjoined tendon per se has a stabilizing effect on stable and unstable shoulders and therefore provide scientific support for the treatment of recurrent shoulder instability using the modified Boytchev procedure.     

Isolated HAGL lesion after arthroscopic Bankart repair in a professional soccer player

Post-traumatic anterior shoulder instability commonly occurs following an avulsion of capsulolabral complex from glenoid (Bankart lesion) or rarely after humeral avulsion of the glenohumeral ligaments (HAGL lesion). Arthroscopic Bankart repair offers high success rates of healing. However, trauma following the treatment may cause implant failure or re-avulsion of the treated tissue. We aim to present the diagnosis and treatment of an isolated HAGL lesion in a professional soccer player who had previously undergone arthroscopic Bankart repair.     

Glenohumeral relationships during physiologic shoulder motion and stress testing: initial experience with open MR imaging and active imaging-plane registration.

PURPOSE: To test the hypotheses that open dynamic magnetic resonance (MR) imaging can (a) be used to evaluate and define normal shoulder motion in active joint motion and muscle contraction and (b) be used in conjunction with physical examination. MATERIALS AND METHODS: With an open-configuration, 0.5-T MR imaging system and active image-plane tracking, 10 shoulders were studied in five asymptomatic subjects to establish normal patterns of glenohumeral motion during abduction and adduction and internal and external rotation. Preliminary studies of physical examination during MR imaging, in which a physician examiner applied mechanical force to the humeral head, were also performed. RESULTS: During abduction and adduction and internal and external rotation maneuvers with active subjects muscle contraction, the humeral head remained precisely centered on the glenoid fossa in all asymptomatic subjects, which is in agreement with findings of previous radiographic studies. Application of force to the humeral head by an examiner was associated with as much as 6 mm of anterior translation and 13 mm of posterior translation. CONCLUSION: Dynamic MR imaging of the glenohumeral joint is possible over a wide range of physiologic motion in vertically open systems. Use of an MR tracking coil enabled accurate tracking of the anatomy of interest. These preliminary measurements of normal glenohumeral motion patterns begin to establish normal ranges of motion and constitute a necessary first step in characterizing pathologic motion in patients with common clinical problems such as instability and impingement.     

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.     

Lipoma arborescens of the glenohumeral joint causing bone erosion: MRI features with gadolinium enhancement

Lipoma arborescens is a rare benign intra-articular lesion that principally affects the knee joint. We present a case of lipoma arborescens involving the glenohumeral joint and associated with prominent large bony erosions. The gadolinium diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (MRI) features of this lesion are also described. The characteristic MRI findings permit precise preoperative diagnosis of this rare condition even if it occurs in an atypical location and there are confusing radiological findings.     

Glenohumeral instability and rotator cuff tear

The prevalence of rotator cuff tears after traumatic dislocation increases with advancing age, a likely consequence of the age-associated deterioration of the structure and mechanical properties of the tendons of the rotator cuff. These are the effective stabilizers of the glenohumeral joint, compressing the humeral head in the 3-dimensional concavity of the glenohumeral joint. It is impossible to establish whether a lesion of the capsular-labrum complex or of the rotator cuff causes or follows a dislocation, regardless of whether it is anterior or posterior. A peripheral nerve or a brachial plexus injury can be associated with tendon lesion and instability, developing the "terrible triad" of the shoulder. Both conservative and surgical management are possible, and surgeons must choose the most appropriate management modality according to the biologic age, functional demands, and type of lesion.