以胸大肌肱骨止点确定肱骨假体高度的临床体会

目的探讨胸大肌肌腱肱骨止点(pectoralismajor tendon,PMT)上缘作为半肩置换术中假体高度定位参考的临床应用。方法2014年1月至2014年12月间行切开解剖复位钢板内固定的肱骨近端骨折病例12例,男4例,女8例;年龄56~72岁,平均(65.3±5.2)岁。测量PMT上缘到肱骨头最高点的平均距离为(5.21±0.42)cm。2015年1月至2018年12月的38例老年严重肱骨近端骨折行半肩置换的患者,参照PMT上缘到肱骨头最高点的距离5.2 cm确定肱骨假体高度,男7例,女31例;年龄60~82岁,平均(72.0±6.5)岁。术后3个月拍摄双侧肱骨全长X线片并测量长度,比较双侧差异是否有统计学意义。根据对侧肱骨长度(humeruslength,HL),采用HL×0.176计算PMT到肱骨头最高点距离,与(5.21±0.42)cm比较差异是否有统计学意义。结果所有患者均随访3个月,半肩置换侧肱骨全长与对侧肱骨全长分别为(32.41±2.47)cm、(31.93±2.82)cm,比较差异无统计学意义。根据对侧HL×0.176计算PMT到肱骨头最高点距离为(5.61±2.82)cm,与(5.21±0.42)cm比较差异无统计学意义。结论PMT可以作为肱骨假体高度的可靠参照,PMT上缘到肱骨头最高点距离为(5.21±0.42)cm,可以作为参考数值之一。     

肱骨近端手术安全区解剖学特点及其临床意义

目的通过尸体解剖测量,寻求肱骨近端手术安全区,为肱骨近端骨折切开复位内固定术的手术入路提供解剖学依据,并探讨手术注意事项。方法取48具肩关节新鲜尸体标本,解剖观察肱骨近端的重要血管及神经,并测量相对于手术切口的标志性骨结构之间的距离。结果肩峰下缘与腋神经上缘的垂直距离为55.4~66.2(60.2±2.2)mm,大结节顶点至腋神经上缘的垂直距离为43.8~51.6(46.9±1.7)mm。大结节顶点至腋神经上缘的距离与肱骨长度的比值为0.147~0.161(0.154±0.0)。肩峰锁骨端下缘与旋肱前动脉上缘的垂直距离为55.8~66.7(60.6±2.1)mm,大结节顶点与旋肱前动脉上缘的垂直距离53.1~61.3(56.2±1.7)mm,大结节顶点至旋肱前动脉上缘的距离与肱骨长度的比值为0.178~0.194(0.185±0.0)。肩峰锁骨端下缘与旋肱后动脉上缘的垂直距离为56.8~68.1(61.3±2.1)mm,大结节顶点与旋肱后动脉上缘的垂直距离47.9~55.7(51.0±1.7)mm,大结节顶点至旋肱后动脉上缘的距离与肱骨长度的比值为0.160~0.176(0.167±0.0)。结论肩峰锁骨端下缘58.0~62.4 mm为腋神经走行区域;大结节下缘54.5~57.9 mm为旋肱前动脉走行区域;肩峰锁骨端下缘59.2~63.4 mm为旋肱后动脉走行区域。在上述3个区域手术操作时,要轻柔仔细,防止损伤神经血管。     

国人肱骨近端三维解剖研究及其对假体设计与植入的影响

目的测量部分国人肱骨近端的三维解剖数据,并与欧美人的解剖数据对比,评估假体设计及假体在术中的定位和安装规范对中国人的适用度。方法正常成人志愿者180例,随机选取单侧肩关节,进行CT扫描,扫描层厚5mm,以1.25mm层厚、0.6mm层间隔进行重建,重建后的图像用Mimics与Imageware软件进行处理,进行三维测量。结果国人平均肱骨全长(29.7±1.9)cm,平均肱骨近端髓腔直径(11.6±1.9)mm,平均肱骨头额状面直径(42.4±4.0)mm,平均肱骨头矢状面直径(40.1±3.9)mm,额状面与矢状面直径比为1.06±0.09,平均肱骨头表面曲率直径(44.6±4.4)mm,平均肱骨头高度(16.7±1.9)mm,肱骨头高度与曲率半径比为0.75±0.07,颈干角平均129.7°±4.3°,肱骨头后倾角平均15.9°±9.2°,肱骨头内侧偏心距平均(5.0±1.6)mm,肱骨头后侧偏心距平均(3.5±1.6)mm。与欧美人相比,只有肱骨近端髓腔直径与肱骨头高度比较,差异无统计学意义,与其他项目比较差异有统计学意义,且国人的肱骨头高度、颈干角、后倾角均与目前手术规范有区别。结论国人与欧美人种的肩关节解剖存在很大差异,应对引进假体进行适当改进,并制定假体在术中的定位与安装标志。     

数字化技术辅助人工肱骨头置换术可行性研究

目的通过CT扫描尸体标本的方法探讨数字化技术辅助下利用自制的定位装置进行个性化人工肱骨头置换术的准确性及可行性。方法对10具双侧上肢尸体标本（包括肩、肘关节）进行CT扫描,利用数字化软件,根据CT扫描数据测量肱骨头高度及后倾角度;制造肱骨近端粉碎性骨折模型20例,运用自制的定位装置在人工肱骨头置换术中重建肱骨头的高度及后倾角度;术后再次测量并对数据进行统计学分析,比较术前术后相关参数的差异。结果 20例模型在人工肱骨头置换术中使用自行研制的定位装置均可有效控制假体高度及后倾角度,手术前测得肱骨头高度平均为（28.57±2.38）cm,肱骨头后倾角平均为（23.0°±5.8°）（11.1°~28.7°）。术后假体高度（t=0.185,P〉0.05）及后倾角度（t=0.481,P〉0.05）与术前相比其差异无统计学意义。结论在人工肱骨头置换术中利用自制的定位装置,可根据健侧测量的数据重建患侧的肱骨头的高度和后倾角度,做到真正的个性化设计和精确的肩关节置换。     

肱骨近端骨折肱骨头置换假体高度的控制

目的:评估利用大结节骨折片复位的方法,确定肱骨近端骨折肱骨头置换假体高度的临床疗效。方法:回顾性研究2015年1月至2019年12月收治并获得随访的肱骨近端骨折患者,符合肱骨头置换指征19例,男7例,女12例;左侧8例,右侧11例;年龄58~84(71.5±5.8)岁;受伤至手术时间3~18(7.9±4.3) d。根据Neer分型,3部分骨折伴脱位2例,4部分骨折17例,其中伴肱骨头脱位6例,肱骨头劈裂2例。19例采用组配式肱骨头假体,在手术过程中,试复位肱骨大结节骨折块,确定肱骨大结节顶点到肱骨标记点的距离,以此距离作为假体高度的标准。术后1年采用Constant-Murley评分,美国加州大学洛杉矶分校(University of California,Los Angeles,UCLA)肩关节评分评价肩关节功能状况及患者满意度。结果:19例均获随访,时间12~58(31.9±14.2)个月。测量手术后上臂长度26~32 cm,双侧比较误差<0.5 cm。术后3个月肩关节正侧位X线片示骨折均愈合。术后1年Constant-Murley评分(80.8±8.9)分,UCLA评分(27.9±4.8)分。术后1年患者满意度89.5%(17/19)。结论:肱骨近端骨折肱骨头假体置换手术过程中,试复位肱骨大结节骨折块,确定肱骨大结节顶点到肱骨标记点的距离,以此距离确定假体高度,方法简单准确,临床效果良好。     

多层螺旋CT后处理测量肱骨头扭转角的实验研究

目的 探讨多层螺旋CT后处理测量肱骨头扭转角的方法.方法 收集51根干肱骨标本,50个肩关节防腐湿标本,行16层螺旋CT扫描,用薄层多平面重组(MPR)、厚层MPR测量肱骨头扭转角,并与容积再现(VRT)测量肱骨头扭转角比较,进行统计学处理.结果 肱骨头扭转角最小值3.3°,最大值57°,101根肱骨头扭转角三种测量方法数据分别为:(25.9±10.9)°、(25.8±10.8)°、(26.0±11.3)°,经统计学处理三种测量方法统计学差异无显著性差异(P>0.05).结论 肱骨头扭转角变异较大,肩关节假体扭转角设计应个性化:多层螺旋CT厚层MPR测量肱骨头扭转角的方法是适用于标本及活体,VRT测量肱骨头扭转角的方法是适用于标本.     

人工肱骨头置换术后并发症的相关研究:双目三维测量装置的应用

目的通过制备肱骨近端四部分骨折模型及成熟的加载测量装置，以进行有关肱骨近端人工关节置换的相关生物力学研究。方法采集新鲜成人肩关节尸体标本8对16具，应用截骨的方法制成肱骨近端四部分骨折模型，对其进行人工假体重建，并分为解剖重建组和重叠重建组。设计并制作模型加载装置及光学测量装置。测定在肩关节处于不同运动角度时，大结节相对于肱骨干骺端的位移情况。检验整套装置是否具有稳定的可重复性。结果成功制成肱骨近端四部分骨折模型。各个标本在肩关节运动至各个不同角度时，多次重复相同的肩关节运动，其大结节的位移值基本一致或相差很小。检测中发现大结节在肩关节活动过程中有明显移位，在个别标本中甚至超过20mm。结论本试验所设计的加载及测量方式可成功模拟肱骨头置换术后肩关节在进行被动活动的过程中，大结节所受的生物力学作用及在此作用下大结节的位移情况。现有的针对人工肱骨头置换的大结节固定方法，在术后即刻的关节被动活动中，仍可导致大结节相对骨干的明显位移。     

人工肱骨头置换术治疗复杂性肱骨近端骨折

[目的]探讨人工肱骨头置换术治疗肱骨近端复杂性骨折的临床疗效.[方法]35例肱骨近端复杂性骨折患者施行人工肱骨头置换术,手术全部采用骨水泥型人工肱骨头假体.手术前后均对患者的肩关节功能进行UCLA评分.[结果]35例患者随访31～63个月(平均52个月),UCLA评分优(34～35分)10例,良(28～33分)21例,中(21～27分)4例,无差病例.术后肩关节活动范围上举(90.6±8.3)°,外旋(64.5±6.5)°,内旋(72.5±5.3)°.病人主观均较满意.所有病例大小结节均愈合,未发现假体松动、感染、脱位等并发症.[结论]严格掌握手术适应证,重建肱骨近端正常解剖和实现大、小结节骨折块的坚强固定,规范的肩关节功能康复锻炼,是人工肱骨头置换术获得满意疗效的关键.     

人工补片肩关节囊重建防治肿瘤型人工肱骨头假体脱位

目的 探讨肿瘤型肱骨头假体置换采用人工补片行肩关节囊重建的方法和临床应用价值.方法 6例肱骨近端肿瘤患者中,初次置换4例,假体脱位翻修2例,置换时将Prolene网状补片一端固定在肩胛盂边缘关节囊上,包绕肱骨头后,另一端固定在肿瘤假体为重建肩袖预制的槽孔内,重建肩关节囊,稳定肩关节.结果 6例均获随访,时间12～28(21 2±64)个月,假体无脱位.肩关节疼痛VAS评分从术前平均7分±0 8分降至术后平均3 1分±1 1分.术后肩关节活动度前屈平均68 9°±14 7°,后伸平均27 5°±8°,外展平均72 7°±16 6°,肱骨旋转活动度平均22 5°±94°.结论 人工补片肩关节囊重建能帮助稳定肩关节,其网状结构还便于术中肩袖及肱骨驱动肌肉的重建,并使肿瘤型肱骨头假体保留良好活动度.     

肱骨近端显微骨硬度分布特征的实验研究

背景:测量分析肱骨近端显微骨硬度分布规律可以较好地评价该部位骨组织不同区域的物理性能。目的:探讨肱骨近端不同部位骨硬度的分布特征及其意义。方法:共选用了62岁男性、45岁女性和58岁男性3具遗体捐献者标本,于肱骨肩关节盂水平及外科颈水平垂直其长轴取多层面标本,使用显微硬度计在样品表面不同区域进行维氏硬度测试,统计分析骨骼硬度的分布规律。结果:3具标本的肱骨近端共测量84个部位,测得肱骨近端区域总体硬度为(37.62±8.82)HV,硬度最大处为肱骨外科颈内侧(45.82±5.55)HV,其次为外科颈外侧与后侧,此三处硬度大于肱骨近端其他部位(P<0.05);硬度最小处为大结节处松质骨(28.32±4.35)HV。从解剖部位来看,外科颈硬度为(44.07±6.45)HV,大于肱骨头及大、小结节硬度(P<0.001);大结节硬度最小为(29.56±5.68)HV(P<0.01)。肱骨头前半部硬度大于后半部,小结节硬度大于大结节,肱骨外科颈前方硬度低于其他方位(P<0.05)。结论:肱骨近端不同区域骨硬度的分布具有规律性;肱骨近端骨硬度分布数据可为肱骨近端内固定策略的选择、新型植入材料的研究提供基础,并为3D打印仿生骨的设计开辟新的视角。     

Pectoralis major tendon reference (PMT): a new method for accurate restoration of humeral length with hemiarthroplasty for fracture

For hemiarthroplasty reconstruction of a proximal humeral fracture, accurate restoration of humeral head position is challenging, and incorrect prosthetic placement is associated with a poor outcome of surgical treatment. The purpose of this study was to validate the pectoralis major tendon as a reproducible landmark for accurate restoration of humeral length with hemiarthroplasty reconstruction. We dissected 20 cadavers (40 shoulders), and the distance between the upper border of the pectoralis major tendon insertion on the humerus and the top of the humeral head was measured (PMT). The PMT averaged 5.6 +/- 0.5 cm (with a confidence level of 95%). In only 4 of 40 shoulders did this distance exceed 6.0 cm, and there was no correlation between the size of the patient and this measurement. The PMT is a useful landmark that will aid in accurate restoration of humeral length when reconstructing complex proximal humeral fractures where landmarks are otherwise lost because of fracture comminution.     

The pectoralis major tendon as a reference for restoring humeral length and retroversion with hemiarthroplasty for fracture

The success of anatomic reattachment of the tuberosities in proximal humeral fractures, treated with hemiarthroplasty, correlates with functional results. The purpose of this study was to determine the value of the upper edge of the pectoralis major insertion (PMI) as a landmark to establish the proper height and version of hemiarthroplasty implanted for proximal humeral fractures. Twenty cadaveric humeri were studied by CT scan to analyze the relationship between the PMI and humeral height and retroversion. The mean distance from the PMI to the tangent to the humeral head was 5.64 cm. The mean distance of the PMI to the posterior fin of the prosthesis was 1.06 cm. The mean angle between the PMI and the posterior fin of the prosthesis was 24.65 degrees. The upper edge of the pectoralis major insertion constitutes a reproducible reference point to restore proper humeral height and retroversion in hemiarthroplasty for proximal humeral fracture.     

Referencing the pectoralis major tendon for humeral stem height placement in reverse shoulder arthroplasty for fracture

BackgroundProximal humerus fractures remain a challenging problem, and reverse total shoulder arthroplasty (RSA) has demonstrated reliable outcomes in fracture applications. Despite this, guidelines for placement of the humeral component are lacking.MethodsTwelve cadaveric shoulders (6 cadaveric torsos) were utilized. An onlay RSA stem was placed with the lateral potion of the humeral cup positioned at the level of the greater tuberosity. Measurements were taken from the top of the pectoralis major tendon to the top of the humeral stem. A separate computer-aided analysis was conducted analyzing the height of an RSA humeral stem and an RSA humeral stem with a cup using values extrapolated from prior data.ResultsThe average distance from the top of the pectoralis to the top of the humeral stem was 4.0 cm (3.4 cm to 4.8 cm) with a standard deviation of 4.1. The humeral cup added an average of 9.1 mm. Computer-aided design data demonstrated the average height of the humeral stem was 3.9 cm above the superior aspect of the pectoralis tendon, and the average height with the humeral cup added was 4.8 cm.ConclusionBoth the cadaveric and computer-aided design data demonstrated a similar height for both the distances from the superior portion of the pectoralis to the superior aspect of an onlay RSA stem and the humeral cup. The measurement from the humeral cup may allow for translational use with inlay RSA humeral stems. This study demonstrates the superior border of the pectoralis major tendon to be a reliable landmark in RSA humeral stem placement.Level of evidenceLevel IV; Cadaveric Study     

Reconstruction of humeral length and centering of the prosthetic head in hemiarthroplasty for proximal humeral fractures

Anatomic reconstruction of humeral length in hemiarthroplasty for complex proximal humeral fractures is difficult because reliable surgical landmarks are missing or are destroyed by the fracture. The pectoralis major tendon is a reliable landmark to determine prosthetic height intraoperatively. This study analyzed the clinical outcome, reconstruction of humeral length, centering of the prosthetic head in the glenoid, and tuberosity positioning and healing, using the pectoralis major tendon as a reference intraoperatively. The study included 30 patients. In 21 patients (group 1), humeral length reconstruction was performed using the pectoralis major tendon as a reference; in 9 (group 2), this reference was not used. Patients underwent a clinical and radiologic evaluation at a mean of 22.7 months. Group 1 showed significantly better results in clinical and radiologic values, especially in anatomic reconstruction of humeral length, than group 2. Clinical outcome depended significantly on greater tuberosity healing and centering of the prosthetic head in the glenoid.     

Humeral lengthening and deformity correction with the multiaxial correction system

Limb lengthening for humeral length discrepancy is typically accomplished using a traditional monolateral external fixator frame or an Ilizarov-type device, which have distinct shortcomings for the correction of concomitant deformity and application to the upper extremity, respectively. A new monolateral frame, the multiaxial correction (MAC) system, provides advantage over other monolateral frames and Ilizarov-type devices for humeral lengthening and may achieve similar outcomes. The purpose of this study was to report on the use of the MAC system for limb lengthening in pediatric patients, each with humeral length discrepancy and deformity. Surgical technique for applying the frame to the humerus is described briefly. A retrospective review of all pediatric patients with humeral length discrepancy treated with the MAC system by one orthopedic surgeon at a major teaching hospital was performed. Clinical data, operative records, and radiographs were reviewed for each patient. A total of three humeri in three children were lengthened over a 3-year period. There were two girls and a boy, with a mean age of 10.3 ± 1.9 years. Etiologies for their discrepancies were osteomyelitis and posttraumatic physeal arrest. Mean initial humeral length discrepancy was 9.4 ± 2.3 cm. All patients had proximal varus deformities, which were partially corrected during treatment. Mean lengthening was 6.5 ± 0.8 cm, and mean healing index was 27.1 ± 4.1 days/cm. Mean follow-up was 23.0 ± 9.9 months. There were no major complications. In conclusion, the MAC system is well suited to the correction of humeral length discrepancies and associated humeral deformities in children. Level of evidence: level IV case series.     

Proximal humerus shaft fracture after pectoralis major tendon rupture repair

Surgical repair of a complete pectoralis major tendon rupture at the humeral insertion has superior results compared to nonoperative treatment. To our knowledge, a proximal humerus shaft fracture occurring at the site of the bone trough and cortical drill holes after a pectoralis major tendon rupture repair has not been reported in the literature.A 45-year-old man sustained an acute left pectoralis major tendon rupture at the humeral insertion while performing a bench press maneuver. He underwent acute surgical repair. Approximately 8 weeks postoperatively, the patient fell from a standing height and sustained a proximal humerus shaft fracture through the repair site at the bone trough. Three days after the fracture, the patient underwent open reduction and internal fixation of the proximal humerus shaft fracture and exploration of the pectoralis major tendon repair. The fracture was found to be at the level of the repair site, and the pectoralis major tendon was completely intact to the distal fragment. The fracture healed uneventfully, and the patient regained full motion and strength of his extremity with no limitations.Any type of surgical fixation that creates a hole in the humerus or decreases the cross-sectional area such as a bone trough creates a stress riser. Patients undergoing pectoralis tendon repair that involves violating the humerus with a bone trough or hole have a slight risk of postoperative humerus fracture, especially if sustaining an early traumatic event such as a fall.     

Repositioning of the humeral tuberosities can be guided by pectoralis major insertion

In complex proximal humerus fractures, positioning of the tuberosities can be a challenge. This study demonstrates the constant angle between the pectoralis major (PM) and the medial lip of the bicipital groove (BG) on the horizontal axial plane. This angle can be used to determine the rotation, as well as the positioning of the tuberosities, when planning a hemiarthroplasty or a reconstruction. Thirty-one shoulder MRIs were reviewed by three independent observers. The measurements were taken by superposing the axial cut of the proximal humerus, at the level of the distal bicipital groove, and the cut at the top of the PM insertion. By aligning the centers of rotation, we could determine the arcs of rotation between the insertion of the PM and the lips of the medial and lateral bicipital groove (MBG and LBG). Both angles were compared in terms of reliability, reproducibility, and precision. The mean PM–MBG angle was 3.7° [standard deviation (SD) 14.7°] and 27.4° (SD 14.4°) for the PM–LBG angle. We obtained good and very good intra-class correlation coefficient (ICC) results for inter- (0.675) and intra-observer (0.793) reliabilities on the medial angle, plus excellent results for the lateral angle (inter-observers 0.962 and intra-observer 0.895). This study demonstrates that the repositioning of humeral tuberosities can be guided by pectoralis major insertion. This will help achieve proper positioning of the metaphysis in relation to the diaphysis during surgery for complex proximal humerus fractures.     

Rupture of the pectoralis major muscle: classification of injuries and results of operative treatment

AIM: Classification of pectoralis major muscle injuries and results of operative treatment in the Sportsklinik Stuttgart between 1998 and 2004 are analysed. METHODS: 10 sportsmen (2 judo, 8 body-building; 9 male, 1 female) with pectoralis major ruptures received operative treatment in this time period. After clinical examination we used ultrasound, in some cases MRI, for further diagnostics. The follow-up (1-5 years) included a clinical examination, ultrasound, sports level, cosmetics and an isokinetic strength assessment. RESULTS: In 4 cases we found a tear of the musculotendinous junction, 4 cases showed a tear at the humeral insertion and 2 other cases had tears of the muscle belly. There was no sports-specific injury. 6 ruptures underwent immediate (1 week) operative therapy and 4 ruptures had delayed (6 weeks to 4 years) repair of the injury. In 9 cases an anatomic repair was possible, in 1 delayed rupture only an extra-anatomic repair was possible. We had 1 complication with a post-operative wound infection. Based on injury localisation and operative treatment, we classified 3 types of pectoralis major ruptures. The follow-up evaluation showed in 7 cases very good and good results, 2 delayed cases still had a cosmetic defect with reduction of strength. CONCLUSION: From our results on pectoralis major muscle injuries there are 3 types of rupture: type 1: rupture at humeral insertion, type 2: rupture of musculotendinous junction, type 3: rupture of muscle belly. This classification is essential for planning the operative technique and the incision. We recommend, after classification of the rupture, primary operative reconstruction of the pectoralis major muscle.     

Anatomic evaluation of the subcoracoid pectoralis major transfer in human cadavers

Subcoracoid transfer of the pectoralis major has recently been described as a reconstruction for subscapularis insufficiency. The purpose of this study was to examine the surgically relevant anatomy of this transfer. The importance of understanding this anatomy was recently highlighted to us following our encounter with musculocutaneous neuropraxia in 2 patients after transfer of the entire pectoralis major, one deep to the musculocutaneous nerve. Dissections were performed on 20 fresh, whole human cadavers in which the entire pectoralis major muscle, medial and lateral pectoral nerves, and musculocutaneous nerve were explored and quantified. The relationship between the pectoralis major and the conjoined tendon was studied in situ and after simulated transfers. The medial and lateral pectoral nerves were located far medial to the pectoralis major tendon insertion and appeared to be safe from injury as long as surgical dissection remained lateral to the pectoris minor and less than 8.5 cm from the humeral insertion. Transfer of the pectoralis major superficial to the musculocutaneous nerve created less tension than transfer deep to the musculocutaneous nerve. Because proximal innervation of the coracobrachialis and short head of the biceps is not an uncommon occurrence, a split pectoralis major transfer, release of the proximal musculocutaneous branches, or debulking of the pectoralis major muscle belly may be required in some instances to prevent tension on the nerve. Because of the variability and location of the musculocutaneous nerve, it should always be visualized operatively. Transfer of the pectoralis major tendon lateral to the biceps tendon appeared to best restore the muscle length-tension relationship.