复发性肩关节前脱位肩盂骨缺损的影像学研究

目的 正确评估复发性肩关节前脱位患者肩盂骨缺损的影像学研究,应用64层螺旋CT扫描三维重建规范化肩盂标准正面观影像.方法 对35例(70侧)成人志愿者的肩盂进行64层螺旋CT扫描,之后在三维工作站上通过重建肩盂的三维图像(去除肱骨头影像),在三个多平面重建和一个三维容积再现重建图像上,通过调整不同平面上的彩色参考线,按标准化确定肩盂标准正面观.为验证该方法的可重复性,三位放射科医师根据上述方法在三维工作站上分别取得肩盂的标准三维正面观影像及标尺,并以二维图像的格式导出,利用AutoCAD软件进行分析.结果 通过测量三位医师在三维工作站上所制作的肩盂正面观的图像,肩盂下部前缘最突点、后缘最突点之间的距离为[(28.1±3.3)mm,下同],肩盂上缘最突点、下缘最突点之间的距离为(38.7±3.7)mm.三位医师所取得正面观影像的测量值之间的差异无统计学意义(P>0.05).结论 根据我们提出的方法,在三维工作站上取得肩盂标准正面观影像是简便、可行的,其可重复性较高,对临床工作中规范化肩盂标准正面观以精确评估肩盂骨缺损具有重要意义.     

肩关节前向不稳中骨缺损诊断技术及评估方法的研究进展

目的总结临床肩关节前向不稳中骨缺损(肩胛盂前缘骨缺损及Hill-Sachs损伤)的诊断及测量方法。方法查阅国内外肩关节前向不稳中骨缺损诊断及评估方法的相关文献,并进行归纳总结。结果临床上用于诊断肩胛盂前缘骨缺损及Hill-Sachs损伤的技术主要包括X线片、CT、MRI、关节镜及关节造影。肩胛盂前缘骨缺损测量方法包括Griffith法、肩胛盂指数法、Pico法、画圆法等;Hill-Sachs损伤主要通过测量其长度、宽度、深度、体积等进行评价。X线片主要用于初步筛查肩关节前向不稳;三维CT画圆的线性法是评价肩胛盂前缘骨缺损最常用方法;基于三维CT的肩胛盂轨迹综合评估法是近年研究热点;MRI及关节镜下测量肩胛盂前缘骨缺损及Hill-Sachs损伤大小的可靠性尚有争议;关节造影技术更多用于诊断肩关节前向不稳中的骨缺损及伴随的软组织损伤。结论如何提高肩关节前向不稳术前骨缺损评估的精准度尚需进一步探索。     

肩关节不稳定的肩盂骨缺损评估:肩盂下部圆心的确定

目的 探讨在正常肩盂CT三维重建标准正面观影像上确定肩盂下部圆心的可行性,比较同一个体左、右肩盂的半径大小,为术前精确定量评估肩盂骨缺损比例提供影像学依据. 方法 本研究测量了35例成人双侧正常肩盂(共70个),每个肩盂均行64层螺旋CT扫描,由1位医生在三维工作站上获得肩盂的标准三维正面观影像及标尺,并将其以二维图像的格式导出.3位医生分别利用AutoCAD2006软件对图像进行处理,做肩盂下部前缘最突点、下缘最突点连线的垂直平分线,再做后缘最突点、下缘最突点连线的垂直平分线,将两垂直平分线的交点定为肩盂下部的圆心,分别测量该点到肩盂前下缘、后下缘和后缘的距离.比较3位医生测量的圆心到肩盂前下缘、后下缘和后缘距离值,以及左、右肩盂相应距离的测量数据. 结果 肩盂下部圆心到肩盂后缘最突点之间的距离(即圆的半径)为(14.1±1.6)mm,到肩盂前下缘的距离为(14.0±1.7)mm,到肩盂后下缘的距离为(14.1±1. 6)mm.3位医生测量的圆心到肩盂后缘距离值之间及左、右肩盂相应测量值之间差异均无统计学意义(P>0.05). 结论 在正常肩盂的CT三维标准正面观影像上利用肩盂下部前、后、下缘最突点确定肩盂下部圆心的方法是简便、可行的,可重复性较高.正常人左右肩盂下部的半径是一致的.以上结论可用于单侧肩盂骨缺损的精确定量评价.     

肩关节前向不稳的诊疗现状及进展

肩关节是全身最容易脱位的关节，其中95%以上为前脱位。初次脱位后处理不当，极易转变为复发性肩关节前脱位或前向不稳，保守治疗效果较差。肩关节前脱位时会损伤维持肩关节稳定性的软组织结构及骨性结构，其中骨性结构是影响肩关节稳定性的最重要因素。诊断需结合患者病史、查体及辅助检查，目前三维CT为最常使用的辅助检查手段，而基于三维CT和关节盂轨迹理论的各种骨缺损测量及术前评估方法各有利弊，尚缺少金标准。目前主流治疗手段包括Bankart修复术、喙突移位术、游离骨移植关节盂重建术、Bankart联合Remplissage术及肩胛下肌腱捆绑填塞术等术式，各有利弊。对于肩关节前向不稳的诊治，仍充满太多未知，需要进一步的研究探索。     

多层螺旋CT和MRI测量肩胛盂斜倾角的互补性初探

目的 探讨多层螺旋CT(MSCT)多平面重组(MPR)及MRI测量肩胛盂斜倾角的互补性.方法 收集成人肩胛骨干标本22侧及肩关节防腐湿标本24侧,用16层螺旋CT扫描仪扫描,多平面重组重建肩胛骨并测量肩胛盂斜倾角,得数据A组.收集MRI检查正常的肩关节病例50侧,取其斜冠状位T1WI显示肩锁关节的层面测量肩胛盂斜倾角,得数据B组.进行统计学处理.结果 肩胛盂斜倾角最小值91.10°,最大值118.50°,A、B 2组肩胛盂斜倾角数据分别为101.14°±4.66°和104.05°±7.72°.2种测量方法肩胛盂斜倾角值统计学上有显著性差异(P＜0.05).结论 MSCT的MPR法测量肩胛盂斜倾角与MRI测量值不同,前者略小于后者;MSCT和MRI 2种测量肩胛盂斜倾角方法结合具有重要的应用价值.     

肩关节镜下简化双滑轮双排缝合锚技术治疗肩盂前缘大块骨折

目的探讨肩关节镜下简化双滑轮(double-pulley)双排缝合锚技术治疗肩盂前缘大块骨折的临床疗效。方法回顾性分析2014年1月至2017年7月,采用肩关节镜下简化double-pulley双排缝合锚技术治疗24例肩盂前缘骨折患者资料,男13例,女11例;年龄(50.14±10.60)岁(范围,34~67岁);均为IdebergⅠa型骨折。其中单纯肩盂前缘骨折8例,伴肱骨大结节骨折4例,伴肩袖损伤5例,伴肩关节前脱位、肱骨大结节骨折4例,伴肩关节前脱位、肩袖损伤2例,伴肩关节前脱位、同侧桡骨远端骨折1例。肩盂前缘骨块面积占肩盂面积的28.91%±5.35%(范围,25.1%~38.5%)。肩关节镜下根据骨块大小,以1枚内排缝合锚置于肩盂前缘骨折床的内缘,2~4枚外排缝合锚置于肩盂关节面边缘,从低到高依次置入缝合锚,通过简化double-pulley技术复位固定。术后观察骨折复位及愈合情况、并发症发生情况。采用Constant-Murley评分、上肢功能障碍评分量表(Disability of Arm,Shoulder and Hand,DASH)对上肢功能进行评价,采用视觉模拟评分(visual analogue scale,VAS)评估疼痛程度。结果24例患者均获得满意骨折复位及内固定,均获得随访,随访时间19.5个月(范围,12~36个月)。手术切口均一期愈合,无一例发生感染、切口愈合不良等;骨折均愈合,愈合时间(2.7±0.6)个月(范围,2.1~3.2个月)。末次随访时,VAS评分为(0.8±0.8)分(范围,0~2分)。术后患肩关节活动度:前屈上举161.00°±5.77°(范围,145°~180°);体侧外旋46.43°±6.63°(范围,35°~60°);内旋拇指触及棘突水平为L3~T10。Constant-Murley评分(88.1±3.7)分(范围,81~93分),DASH评分(8.4±4.7)分(范围,0~40.4分)。除1例患者术后6周CT检查显示肱骨头向前下略移位外,其余患者肩关节对应正常,无脱位和不稳定表现。术后即刻及术后3、6、12个月CT检查均未见骨折块移位。CT检查评价关节面复位情况,术后即刻19例关节面台阶<2 mm,5例2~4 mm;末次随访时19例关节面台阶<2 mm,4例2~4 mm,1例>4 mm。术后6周,1例患者CT检查示肱骨头向前下略移位,但术后3个月CT检查示盂肱关节对应关系基本正常,关节面台阶5 mm。末次随访时,24例患者均未见严重骨关节炎表现,其中1例67岁患者存在轻度骨关节炎表现。2例伴肩关节前脱位及肩袖损伤者肩关节活动明显受限。结论对于大的肩盂前缘骨折,采用肩关节镜下简化double-pulley双排缝合锚固定技术治疗,创伤小,术中镜下视野清晰,骨折显露安全、充分,复位、固定稳定可靠,可获得满意疗效。     

基于三维重建技术的国人肩关节盂三维形态学测量与研究

目的利用三维重建和扫描图像校正技术对国人正常关节盂形态指标进行评估。 方法整理吉林大学中日联谊医院2013年1月至2017年6月间收治的98例国人正常肩关节CT扫描数据。其中男性36例,女性62例,年龄21~80岁,平均（51±14）岁。将患者CT数据导入Mimics软件并行三维CT重建,建立肩胛骨平面对扫描图像进行重新校正,避免扫描角度和患者姿势的影响。利用3-matic和Geomagic软件将关节盂曲面拟合成3D散点模型以确定关节盂中心和关节盂拟合平面。定量分析正常国人关节盂的高度、宽度、曲面面积、扭转角和倾斜角。 结果正常国人关节盂高度为（35.2±2.9）mm,宽度为（26.9±2.6）mm,曲面面积为（824±143）mm²;扭转角为后倾（1.01±4.07）°,倾斜角为上倾（8.89±4.71）°,以上测量参数均无侧别统计学差异。而男性关节盂高度、宽度及曲面面积显著大于女性（P<0.01）。相关性分析表明,身高与关节盂尺寸存在显著正相关（r=0.815,P<0.01）。 结论利用三维重建技术对关节盂进行形态学参数分析,具有较高的准确性和可重复性,对优化国人关节盂假体设计具有一定参考价值。基于欧美人设计的商用标准29 mm型关节盂假体尺寸较大,理论上适用于身高超过175 cm的国人。     

肩关节立位X线测量及其临床意义

目的　探讨肩关节悬挂结构损伤的简便诊断方法。方法　对 10 1例正常人和 2 6例肩关节脱位患者立位肩关节X线正位片的测量结果进行比较。结果　两组在盂高、盂肱间隙值上差异无显著性 (P >0 0 5 ) ,K截距、肩肱间隙、K截距 /盂高 (KN/GH)差异有显著性 (P <0 0 1、P <0 0 5、P <0 0 1)。另外 ,两组肩肱间隙的变异系数分别为 15 0 15 %、198 46 % ,而KN/GH的变异系数分别为18 76 %、13 2 1%。结论　KN/GH稳定而精确 ,肩关节立位X线正位片上很容易测量。当此值 >0 6 ,应高度怀疑有悬挂结构损伤     

肩盂骨性缺损致肩关节前方不稳定的生物力学研究

目的评价肩盂前下方骨性结构在肩关节前方稳定性中的生物力学特性和作用,为临床治疗肩盂骨性缺损提供理论依据。方法于自愿捐献的成年男性新鲜尸体取带肩胛骨的肩关节-肱骨标本10具,制备为"骨-韧带"标本;左侧4具,右侧6具。分别于肩关节外展0、90°位时,采用Instron 8874液压伺服生物力学测试系统给予肱骨头50 N的单轴压缩,每个标本按照完整肩关节、盂唇缺损、骨性缺损10%、骨性缺损20%、骨性缺损修复顺序,测量标本位移值。结果肩关节外展0°位时,完整组、盂唇缺损组、骨性缺损10%组、骨性缺损20%组、骨性缺损修复组位移分别为(10.73±2.93)、(11.43±3.98)、(13.58±4.86)、(18.53±3.07)、(12.77±3.13)mm;90°位时,分别为(8.41±2.10)、(8.55±2.28)、(9.06±2.67)、(12.49±2.32)、(8.55±2.15)mm。除骨性缺损20%组与完整组比较差异有统计学意义(P<0.05)外,其余各组与完整组比较差异均无统计学意义(P>0.05)。结论肩盂前下盂唇缺损或骨性缺损<20%时,如关节囊韧带复合体未损伤或已修复,肩关节前方稳定性无明显下降;肩盂骨性缺损≥20%时,即使修复关节囊韧带复合体,肩关节前方稳定性仍明显下降;而同时修复骨性缺损和关节囊韧带复合体可恢复肩关节前方稳定性。     

肩关节前向不稳的治疗选择

肩关节是体内最不稳定及最常脱位的关节,肩关节前向不稳是指肩关节前方不稳定引起的肩关节复发性前脱位,一般是由外伤引起.肩关节前向不稳发生的机制是外伤发生脱位后,肱骨头与前下方关节盂撞击导致前下关节囊韧带复合体损伤(Bankart损伤),甚至关节盂骨缺损(骨性Bankart损伤).同时,一些患者也会由于反复的磨损撞击产生肱...     

Is CT scan a predictor of instability in recurrent dislocation shoulder?

Purpose: Glenoid bone defect and the defect on the posterior-superior surface of the humerus “HillSachs lesion” are the commonly seen bony lesions in patients with recurrent dislocation shoulder. Computed tomography (CT) scan is considered as the best option in assessing the bony defects in the recurrent dislocation shoulder. The aim of this study was to assess the clinical and radiological corelation in the patients with recurrent dislocation shoulder. Methods: Forty-four patients of recurrent dislocation shoulder who were evaluated between January 2015 and December 2017 at a tertiary care center, clinically and radiologically using CT scan and meeting the inclusion criteria, were included. The correlation between the clinical history of the number of dislocations and the bone loss using CT scan was evaluated. Two sided statistical tests were performed at a significance level of a = 0.05. The analysis was conducted using IBM SPSS STATISTICS (version 22.0). Results: All the patients were male with mean age of 25.95 (SD ± 4.2) years were evaluated. Twenty-four patients sustained injury in sporting activities while 20 patients sustained injury in training. There were an average of 4.68 (SD ± 3.1, range 2-15, median 3) episodes of dislocation. Forty-one patients had the glenoid bone loss while 40 had the Hill-Sachs lesions. The mean glenoid width defect was 10.80% (range 0-27%) while the mean Hill-Sachs defect was 14.27 mm (range 0-26.6 mm). The mean area of bone loss of the glenoid surface was 10.81% (range 0-22.4%). The lesions were on track in 34 patients and off track in 10 patients. Conclusions: CT scan of the shoulder joint is an effective method for assessing the amount of bone loss. The number of dislocations are correlated significantly with off-track lesions and the amount of bone loss on the glenoid and Hill-Sachs lesion. The glenoid width bone loss of more than 9.80% or Hill-Sachs defect of more than 14.80 mm are the critical defects after which the frequency of dislocations increases.     

Osseous Defects Seen in Patients with Anterior Shoulder Instability

Shoulder surgeons need to be aware of the critical size of the glenoid or humeral osseous defects seen in patients with anterior shoulder instability, since the considerable size of osseous defect is reported to cause postoperative instability. Biomechanical studies have identified the size of the osseous defect which affects stability. Since engagement always occurs between a Hill-Sachs lesion and the glenoid rim, when considering the critical size of the Hill-Sachs lesion, we have to simultaneously consider the size of the glenoid osseous defect. With the newly developed concept of the glenoid track, we are able to evaluate whether a large Hill-Sachs lesion is an "on-track" or "off-track" lesion, and to consider both osseous defects together. In case of an off-track Hill-Sachs lesion, if the glenoid defect is less than 25%, no treatment is required. In this case, the Latarjet procedure or arthroscopic remplissage procedure can be a treatment option. However, if the glenoid defect is more than 25%, treatment such as bone grafting is required. This will convert an off-track lesion to an on-track lesion. After the bone graft or Latarjet procedure, if the Hill-Sachs lesion persists as off-track, then further treatment is necessitated. In case with an on-track Hill-Sachs lesion and a less than 25% glenoid defect, arthroscopic Bankart repair alone is enough.     

Shoulder Instability in the Setting of Bipolar (Glenoid and Humeral Head) Bone Loss: The Glenoid Track Concept

Background

An assortment of variables has been used in predicting anterior shoulder instability resulting from pathologic engagement of Hill-Sachs lesions on the glenoid. The glenoid track is a unique biomechanical model that relates both Hill–Sachs and bony Bankart lesions to predict shoulder engagement. We examined the glenoid track concept to determine if it provides a model that unifies glenoid rim and humeral head bone loss in predicting engagement.

Questions/purposes

In this review we addressed two questions: (1) How are humeral head and glenoid rim bony defects and their interactions quantified? (2) Why is the concept of the glenoid track important?

Methods

We performed a systematic review of the literature using PubMed (MEDLINE) and OVID for biomechanical studies and peer-reviewed articles published until March 2013. Twenty-four studies fit the inclusion criteria. These were subdivided into four anatomic studies, four studies quantifying glenohumeral bone loss, nine studies biomechanically defining shoulder engagement, six studies analyzing current treatment models, and one clinical study to be included in the final review.

Results

Data demonstrate pathologic engagement is dependent on the medial margin of the Hill–Sachs lesion traveling outside the glenoid track. The width of the glenoid track decreases accordingly if there is a glenoid defect, making engagement more likely. Most treatment models focus on widening the glenoid track before addressing Hill–Sachs lesions.

Conclusions

The glenoid track uses both glenoid and humeral head bone loss to predict subsequent risk of humeral head engagement and possible dislocation. The glenoid track shows us that restoring the track to its natural width should be among the surgeon’s first priority in restoring shoulder stability. Humeral head lesions, also known as Hill–Sachs lesions, are surgically addressed when they cause clinical symptoms. Symptoms arise when the medial margin of the defect engages the glenoid track.     

复发性肩关节前脱位关节镜手术治疗进展

复发性肩关节前脱位的手术治疗是运动损伤医学领域中的一个难题,其主要原因在于无法较好地恢复肩关节动力性及骨性约束.目前国内外大多采用关节镜手术治疗,术后总体效果满意,但具体术式的选择仍存在较大争议.临床中需根据关节盂及肱骨头骨性缺损的有无及大小,选择不同方案治疗.笔者建议:无关节盂骨性缺损或关节盂骨性缺损＜20％,选用B...     

Management of Complex and Revision Anterior Shoulder Instability

Treatment of recurrent anterior shoulder instability has gained significant interest in recent years and involves evaluation of both glenoid and humeral sided bone loss. Decision making is more complex in patients with significant humeral or glenoid bone defects or in those who underwent previous instability surgery. Appropriate assessment of the glenoid track is necessary as “off track” lesions typically require treatments beyond arthroscopic labral repair alone. In those with significant humeral or glenoid sided bone loss, the authors recommend three-dimensional computed tomography in addition to magnetic resonance imaging for accurate evaluation. The Glenoid Track Instability Management Score is a useful guide to help direct treatment by using the glenoid track as well as other known risk factors for recurrence. In circumstances with significant glenoid bone loss, typically over 20%, a coracoid transfer such as the Latarjet is recommended. In patients that previously failed a coracoid transfer, the authors recommend a distal tibia allograft; however, distal clavicle and iliac crest autograft have also been reported to have high success rates. In those with large Hill-Sachs lesions, remplissage or bone grafting are recommended. An estimation of the postoperative glenoid track after glenoid bone augmentation is required for appropriate Hill-Sachs lesion treatment. The authors typically recommend against revision instability surgical treatment with arthroscopic repair alone.     

Editorial Commentary: Remplissage Is Not Needed When Performing the Latarjet Procedure in the Setting of Off-Track Hill-Sachs Lesions: One of the Classics Continues to Get Better With Age (and Some Help From New Data)

The glenoid track paradigm has played a pivotal role in the development of a contemporary approach to shoulder stabilization surgery. A number of studies have validated the importance of bipolar bone loss in the pathogenesis of recurrent anterior shoulder instability and defined the limitations of soft tissue–based, arthroscopic surgical approaches. The glenoid track paradigm has also helped to clarify the indications for coracoid transfer procedures, although some question persists as to the necessity of addressing an “off-track” Hill-Sachs lesion with remplissage concurrently with the Latarjet procedure for large glenoid bone defects. The best available evidence would suggest that the Latarjet procedure can be expected to yield favorable clinical outcomes even in the setting of an off-track Hill-Sachs lesion, thereby obviating the necessity of concomitant remplissage for cases involving advanced degrees of bipolar bone loss.     

Remplissage Versus Latarjet for Engaging Hill-Sachs Defects Without Substantial Glenoid Bone Loss: A Biomechanical Comparison

Background

Recurrent shoulder instability is commonly associated with Hill-Sachs defects. These defects may engage the glenoid rim, contributing to glenohumeral dislocation. Two treatment options to manage engaging Hill-Sachs defects are the remplissage procedure, which fills the defect with soft tissue, and the Latarjet procedure, which increases glenoid arc length. Little evidence exists to support one over the other.

Questions/purposes

We performed a biomechanical comparison of the remplissage procedure to the traditional Latarjet coracoid transfer for management of engaging Hill-Sachs defects in terms of joint stiffness (resistance to anterior translation), ROM, and frequency of dislocation.

Methods

Eight cadaveric specimens were tested on a shoulder instability simulator. Testing was performed with a 25% Hill-Sachs defect with an intact glenoid and after remplissage and Latarjet procedures. Joint stiffness, internal-external rotation ROM, and frequency of dislocation were assessed. Additionally, horizontal extension ROM was measured in composite glenohumeral abduction.

Results

After remplissage, stiffness increased in adduction with neutral rotation (12.7 ± 3.7 N/mm) relative to the Hill-Sachs defect state (8.7 ± 3.3 N/mm; p = 0.016). The Latarjet procedure did not affect joint stiffness (p = 1.0). Internal-external rotation ROM was reduced in abduction after the Latarjet procedure (49° ± 14°) compared with the Hill-Sachs defect state (69° ± 17°) (p = 0.009). Horizontal extension was reduced after remplissage (16° ± 12°) relative to the Hill-Sachs defect state (34° ± 8°) (p = 0.038). With the numbers available, there was no difference between the procedures in terms of the frequency of dislocation after reconstruction: 84% of specimens (27 of 32 testing scenarios) stabilized after remplissage, while 94% of specimens (30 of 32 testing scenarios) stabilized after the Latarjet procedure.

Conclusions

Both procedures proved effective in reducing the frequency of dislocation in a 25% Hill-Sachs defect model, while neither procedure consistently altered joint stiffness.

Clinical Relevance

In the treatment of shoulder instability with a humeral head bone defect and an intact glenoid rim, this study supports the use of both the remplissage and Latarjet procedures. Clinical studies and larger cadaveric studies powered to detect differences in instability rates are needed to evaluate these procedures in terms of their comparative efficacy at preventing dislocation, as any differences between them seem likely to be small.     

Reliability of measurements performed on two dimensional and three dimensional computed tomography in glenoid assessment for instability

Purpose

The main purpose of this study is to establish which of two methods is more reliable in glenoid assessment for instability in pre-operative planning. Accordingly, we have studied the intra- and inter-observer reliability of glenoid parameters with the use of two-dimensional (2D) and three-dimensional (3D) reconstructed computed tomography (CT) images.

Methods

One hundred glenoids were measured with the use of 2D-CT and 3D-CT (in 3D orientation) by two independent observers (one experienced and one inexperienced). Measurements were repeated after one week for 30 randomly selected glenoids.

Results

The intra-class correlation coefficient (ICC) for inter-observer reliability was significantly greater for 3D-CT (0.811 to 0.915) than for 2D-CT (0.523 to 0.925). All intra-observer reliability values for 3D-CT were near perfect (0.835 to 0.997), while those for 2D-CT were less reliable (0.704 to 0.960). A dependent t-test showed that, for both observers, almost all glenoid parameters (except R and d) differed significantly (p?<?0.05) between 2D and 3D measurement methods.

Conclusions

Therefore, it can be concluded that 3D glenoid reconstructions are more reliable for glenoid bone loss assessment than 2D-CT. The results suggest that quantifying a glenoid defect with the use of 2D image only—even if performed by an experienced orthopaedic surgeon—is prone to errors. Differences in measurements between and within observers can be explained by plane setting and identifying glenoid rim in 2D-CT. Accordingly, we recommend that glenoid measurements should be performed in 3D orientation using 3D reconstruction obtained from CT images for pre-operative assessments, which are crucial for surgical planning.

     

3-D CT is the Most Reliable Imaging Modality When Quantifying Glenoid Bone Loss

Background

Posttraumatic anterior shoulder instability is associated with anterior glenoid bone loss, contributing to recurrence. Accurate preoperative quantification of bone loss is paramount to avoid failure of a soft tissue stabilization procedure as bone reconstruction is recommended for glenoid defects greater than 20% to 27%.

Questions/purposes

We determined whether radiography, MRI, or CT was most reliable to quantify glenoid bone loss in recurrent anterior shoulder instability.

Methods

Seven intact fresh-frozen human cadaveric shoulders were imaged with radiography, MRI, CT, and three-dimensional (3-D) CT. Three sequential anterior glenoid defects then were created, measured, and the shoulders reimaged after each defect. Defect sizes were less than 12%, 12% to 25%, and 25% to 40%. The gold standard measurement was determined by comparing measurements taken on the cadaver by two surgeons using digital calipers with the measurements determined by using electronic digital calipers on the 3-D CT. This measurement was used for comparison of all estimations by the evaluators. Twelve independent blinded evaluators reviewed the 112 image sets and estimated the percent of glenoid bone loss. Images were scrambled and rereviewed by the same observers 2 months later to determine intraobserver reliability. We determined reliability with kappa values.

Results

Kappa values between predicted bone loss versus true loss (determined by our gold standard measurements) across all 12 raters for each modality were: 3-D CT, 0.50; CT, 0.40; MRI, 0.27; and radiographs, 0.15. Interobserver agreement (kappa) values were: 3-D CT, 0.54; CT, 0.47; MRI, 0.31; and radiographs, 0.15. The intraobserver agreement (kappa) values were: 3-D CT, 0.59; CT, 0.64; MRI, 0.51; and radiographs, 0.45.

Conclusions

Three-dimensional CT was the most reliable imaging modality for predicting glenoid bone loss. Regular CT was the second most reliable and reproducible modality.     

复发性肩关节前脱位伴骨缺损的治疗进展

复发性肩关节前脱位伴骨缺损是肩关节常见疾病之一。如何有效地修复关节盂骨缺损,降低肩关节脱位复发率是临床医师关注的问题。骨移植术能够发挥骨刺激作用,促进骨再生和骨重塑,恢复关节盂的正常解剖结构。其中,Bristow-Latarjet术是治疗复发性肩关节脱位的经典术式,Latarjet术能够修复更大的关节盂骨缺损,但对手术医师的操作要求更高;自体髂骨移植术是Latarjet术失败后翻修的首选方案;骨软骨移植术(自体和异体)在重建原始关节面和预防关节退行性改变方面有一定的优势,但自体骨软骨移植术会造成二次损伤,而异体骨软骨移植术的免疫排斥难以避免。随着复合材料的改进,对骨再生、重塑机制的探究,以及结合骨移植术的优缺点,组织工程技术将来有可能成为治疗关节盂骨缺损的重要方法。