Magnetic resonance imaging versus arthroscopy for the investigation of the osteochondral humeral defect in anterior shoulder instability

A double-blind prospective study was done with 15 patients with anterior shoulder instability to determine the diagnostic efficacy of magnetic resonance (MR) imaging versus arthroscopy in the evaluation of chondral or osteochondral lesions of the humeral head. MR produced 6 true positives, 5 true negatives and 4 false negatives, and its accuracy and sensitivity were 60% and 87%, respectively, whereas arthroscopy gave 8 true positives, 5 true negatives and 2 false negatives, with a sensitivity of 80% and an accuracy of 87%. All lesions diagnosed with either method were regarded as positive by definition, with the result that the specificity was always 100%. The differences in diagnosis sprang from the false negatives. The 40% discrepancy between the two methods was probbly due to our distinction in MR between intra- and extraarticular osteochondral lesions. In the first group (the 4 MR false negatives), there were three instances of firstdegree intra-articular lesion and one diagnostic error (third-degree lesion). In the second (the 2 arthroscopy false negatives), the lesions were of the extra-articular type. It is thus advisable to employ both of these methods to ensure the correct diagnosis of a Hill-Sachs lesion, and hence the correct choice of treatment.     

Pathomechanics of the throwing shoulder

Many anatomic, physiological, and biomechanical alterations have been observed in overhead athletes who present with painful shoulders. This is probably due to the complex kinetic chain mechanics required in the overhead throwing or serving motion. Any alteration along the kinetic chain can result in deficits in force production or increase in joint loads in other parts of the chain. The "disabled throwing shoulder" (DTS) is a general term that describes the limitations in function that exist in symptomatic overhead athletes. DTS typically results from a "cascade to injury" with alterations in the kinetic chain. Evaluation of athletes with the DTS should include examination of the local and distant anatomic injuries and screening for physiological (muscle inflexibilities, weakness, or imbalances) or biomechanical (motions, positions) alterations.     

Rehabilitation of the throwing shoulder

Rehabilitation of the injured throwing arm should not be directed simply toward beginning strengthening exercises and returning the athlete to throwing as soon as possible. The total comprehensive program has been described and consists of seven phases that begin with making the proper diagnosis of a shoulder injury. Once the proper diagnosis is made, the pathophysiology of throwing injuries has to be understood by the physician, the trainer, and the athlete, and then the actual treatment begins in phase III. Initial treatment many times consists of a short period of relative rest as well as physical therapy modalities to relieve pain, and once pain is relieved phase IV begins, which is the actual techniques of range of motion, flexibility, and strengthening maneuvers. Once adequate flexibility, range of motion, and pain-free motion have been achieved, as well as adequate endurance strength, proper warm-up techniques are begun, and then a return to throwing is achieved in phase VI. The total rehabilitative cycle is concluded with phase VII, which consists of an off-season conditioning program to verify that the athlete will maintain year-round maximum condition of not only the throwing shoulder but of the entire athlete.     

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.     

Graded stress radiography of injured anterior cruciate ligaments.

Fifty-five patients with clinical suspicion of injury to their anterior cruciate ligament (ACL) were examined by graded stress radiography before arthroscopic verification in an effort to determine the loss of ACL function as a result of ligament tearing. Using a commercially available stress device capable of applying varying pressures to the mid-calf, anterior drawers were measured from lateral radiographs at 0-, 7-, 14-, and 21-kiloPascal pressures and used to calculate the equivalent elastic modulus of the remaining ACL fibers. According to viscoelastic theory, this modulus is proportional to the number of elastically active fibers in the ligament. To verify the validity of this concept, the stress-strain relationship of a freshly excised ACL ligament was examined in a tensile testing machine, and the procedure was repeated after the ligament had been partially transsected with a scalpel. Comparison with the elastic modulus of the (intact) ACL of the opposite knee permits an estimate of the percentage of rupture in cases of partial tears. Overstretched ligaments show essentially normal viscoelastic properties once the slack in the ligament has been taken up. Complete tears, on the other hand, show a complete breakdown in the viscoelastic properties of the ACL. The results show that partial tears can be diagnosed by graded stress radiography with a sensitivity of 20% and specificity of 90%. Diagnosis of overstretched ligaments had sensitivity of 50% and specificity of 94%. Complete tears were detected with sensitivity of 88% and specificity of 75% as diagnosed against all other ACL lesions and including normals.(ABSTRACT TRUNCATED AT 250 WORDS)     

Stroboscopic computerized determination of humeral rotation in overarm throwing.

Analysis of the final phase of the overarm handball throw was carried out by a microcomputerized treatment of photographic images taken simultaneously in two grid layouts. Reflective stickers on the joints of the throwing arm (shoulder, elbow, wrist) allowed the coordinates of these three points to be measured against a reference on the wall. Using a mathematical treatment and Euler matrices, the movement could be studied in space. The results confirmed that humeral rotation occurs during the overarm handball throw. Initial external rotation was immediately followed with internal rotation about 40 ms before ball release.     

Imaging of the painful shoulder in throwing athletes

A wide spectrum of abnormalities can affect the throwing shoulder. The injuries are often particular to a specific phase of the throw and are well demonstrated with MR imaging. In this article, the authors review the phases of the throw, MR imaging techniques, and the MR appearances of the injuries associated with particular phases.     

Radiologic assessment of humeral head retroversion. Description of a new method

A radiologic method for assessment of the humeral head retroversion angle has been developed using one radiograph obtained in the semi-axial view. Validity and reliability of the method has been tested. In five healthy volunteers both shoulders were examined both with CT and with the new radiographic method. The average difference in angle determinations between the methods was 1.5 degrees and the maximum difference was 2 degrees. Angle determination on radiographs from 22 healthy shoulders was performed by two independent radiologists. The coefficient of variation for intraobserver measurements was 2.8 per cent and for interobserver measurements it was 4.6 per cent. Three isolated humerus bones were examined in multiple semi-axial projections and the humeral head retroversion was measured. The effect of humeral position (flexion, extension, abduction) on angle assessments was analyzed. A method error exceeding 2 degrees was only seen when the specimens were in an extended or extremely abducted position. It is concluded that with the arm in the correct position measurements of humeral head retroversion can be performed with this method with high accuracy.     

Soft tissue radiography in painful shoulder.

Specialized soft tissue radiography was applied to the shoulder region to differentiate between shoulder peritendinitis and radiating cervical pain. The technique is presented, together with the results of a clinical trial. Local inflammation was demonstrable even in the absence of calcific deposits.     

Conventional radiography of the shoulder

Conventional radiography is a useful tool in the evaluation of shoulder pain whether in the setting of acute trauma or chronic pain and in most clinical situations should be the first imaging modality performed. Knowledge of the various projections and radiographic findings described above will ensure an optimal evaluation of the shoulder regardless of the suspected etiology of the shoulder pain.     

Overhead throwing injuries of the shoulder and elbow

Injuries to the shoulder and elbow are common in athletes involved in sporting activities that require overhead motion of the arm. An understanding of the forces involved in the throwing motion, the anatomic structures most at risk, and the magnetic resonance imaging appearances of the most common associated injuries can help to improve diagnostic accuracy when interpreting imaging studies in these patients.     

Imaging of shoulder pain in overhead throwing athletes

Overhead sports are widely practiced around the world and overhead athletes can present with pain and dysfunction in the throwing shoulder, generally due to degenerative changes secondary to overuse. Numerous etiologies can be taken into account, including rotator cuff and glenoid labrum tears, biceps pathologies, internal impingement, and gleno-humeral instability. In this setting, imaging plays a central role in early diagnosis, thus allowing for a prompt management, correct rehabilitation, and quick return to competition. This review is aimed to discuss the role of imaging to diagnose the most common types of overhead-related shoulder injuries.     

人工肱骨头假体置换与锁定板治疗复杂肱骨近端骨折的疗效对比

目的比较人工肱骨头假体置换与锁定板治疗复杂肱骨近端骨折的疗效。方法回顾性分析2013—2016年南通大学附属南京江北人民医院创伤关节外科收治的32例复杂肱骨近端骨折患者的临床资料,其中采取人工肱骨头假体置换治疗16例(置换组),采取锁定钢板内固定治疗16例(内固定组)。比较两组患者一般手术情况、临床疗效、术后4周时VAS评分及Constant-Murley评分。结果 (1)两组患者在手术时间、术中出血量及一次性手术费用比较方面差异无统计学意义(P0.05);(2)置换组Neer评分优良率为75.00%,内固定组Neer评分优良率为81.25%,两组比较差异无统计学意义(P0.05);(3)置换组VAS评分(2.14±0.52)分,内固定组VAS评分(2.37±0.61)分,两组比较差异无统计学意义(P0.05);(4)置换组Constant-Murley评分(65.28±13.04)分,内固定组Constant-Murley评分(61.44±11.62)分,两组比较差异无统计学意义(P0.05)。结论人工肱骨头假体置换与锁定板治疗复杂肱骨近端骨折的手术时间、术中出血量及手术花费无明显差异,术后疗效相近。术式的选择主要依赖骨折复杂程度和患者一般状况。     

An EMG analysis of the shoulder in throwing and pitching. A preliminary report

Five male subjects' throwing and pitching motions were analyzed by dynamic electromyography and high speed photography. Electrodes inserted into the deltoid and rotator cuff muscles attempted to define muscle activation patterns during the throwing and pitching cycle. The wind-up or preparation (Stage I) had no consistent pattern. Cocking (Stage II) had a sequential muscle activation pattern of first deltoid activity, followed by the S.I.T. muscles and finally by the subscapularis muscle. Acceleration (Stage III) had a lack of muscle activity, even though the arm was accelerating forward in space. Follow-through (Stage IV) was the most active stage with all the muscles firing intensely. The muscle patterns observed during the cycle were largely characteristic of attempts to decelerate the arm.     

DR系统/屏-片组合在头颈部摄影的应用探讨

随着信息技术的不断发展,X线摄影已进入数字化时代,直接数字X线摄影(D igital R adiography),能为影像诊断提供目前最为优质理想的影像信息。本文通过D R系统与传统屏-片系统在头颈部所摄的影像进行比较,探讨D R系统在临床头颈部X线摄影中的优势。1材料与方法设备美国G E公司的R evolution X R/d直接X线数字摄影系统(D R)、D IC O M3.0图像存储与传输标准,w ork station处理工作站,曝光电压75kV,管电流320m A,靶距离70cm～100cm。岛津摄片机U D150L—30E,A gfaC PG4008×10感绿片暗盒,K O D A K套药,kodak M7B自动洗片机,曝…     

Axillary projection in radiography of the nontraumatized shoulder

A series of 239 consecutive radiographic examinations of the shoulder performed on patients without acute trauma was analyzed prospectively. Each examination included anteroposterior projections with external and internal rotation of the humerous and an axillary projection. The abnormalities that could be identified on each view were listed separately. There were 109 normal examinations and 130 abnormal examinations. The anteroposterior view with external rotation identified 14 abnormalities not seen on the other views. The axillary projection identified 15 abnormalities not seen on other views. If only these two views had been obtained, 99.3% of the abnormalities would have been identified. The implications for altering routine film series are discussed.