Accuracy of patient-specific instrumentation in anatomic and reverse total shoulder arthroplasty

Purpose:Glenoid component malposition is associated with poor function and early failure of both anatomic and reverse total shoulder arthroplasty. Glenoid positioning is challenging particularly in the setting of bone loss or deformity. Recently, the use of computer assistance has been shown to reduce implantation error. The aim of this study is to evaluate the accuracy of patient-specific instrumentation in cases of anatomic and reverse shoulder replacement in vivo.Methods:Twenty patients underwent total shoulder arthroplasty using a computed tomography (CT)-based patient-specific instrumentation (PSI) system, ten anatomic and ten reverse. Preoperative three-dimensional digital templating of glenoid component position was undertaken and surgery then performed using a custom-made guide. Postoperative CT scans were used to compare final implanted component position to the preoperatively planned position in the same patient.Results:Final component position and orientation closely reflected the preoperatively templated position. Mean deviation in the glenoid version from planned was 1.8° ±1.9° (range, 0.1°–7.3°). Mean deviation in inclination was 1.3° ±1.0° (range, 0.2°–4.5°). Mean deviation in position on the glenoid face was 0.5 ± 0.3 mm (range, 0.0–1.3 mm) in the anteroposterior plane and 0.8 ± 0.5 mm (range, 0.0–1.9 mm) in the superoinferior plane. Actual achieved version was within 7° of neutral in all cases except for one where it was deliberately planned to be outside of this range.Conclusion:PSI in both anatomic and reverse shoulder arthroplasty is highly accurate in guiding glenoid component implantation in vivo. The system can reliably correct bony deformity.     

肩关节不稳与SLAP损伤联系的研究进展北大核心CSCD

目的总结肩关节不稳与上盂唇自前向后(superior labrum anterior posterior,SLAP)损伤的联系。方法通过查阅国内外相关研究文献,分析肩关节不稳与SLAP损伤的特点,归纳并探讨两者在发病机制、临床症状及生物力学上的关联。结果肩关节不稳和SLAP损伤既可同时存在,也可单独发生。SLAP损伤由于破坏了上盂唇的完整性和肱二头肌长头腱(long head of biceps tendon,LHBT)止点,可引起肱骨头相对关节盂过度移位,导致肩关节不稳。而慢性反复性或急性高能量创伤导致的肩关节不稳也会加重SLAP损伤,造成原有损伤范围扩大及撕裂程度加重。结论 SLAP损伤会破坏肩关节稳定机制,肩关节不稳会引起上盂唇和LHBT撕裂,两者间存在一定联系。然而,现有研究结果仅能证明肩关节不稳和SLAP损伤之间具有互相诱发和促进发展的关系,而非互为充分必要条件,因此两者间具体因果关系还需进一步深入研究。     

Thinking outside the glenohumeral box: Hierarchical shape variation of the periarticular anatomy of the scapula using statistical shape modeling

Variation in the shape of the glenoid and periarticular anatomy of the scapula has been associated with shoulder pathology. The goal of this study was to identify the modes of shape variation of periarticular scapular anatomy in relation to the glenoid in nonpathologic shoulders. Computed tomography scans of 31 cadaveric scapulae, verified to be free of pathology, were three-dimensionally reconstructed. Statistical shape modeling and principal component analysis identified the modes of shape variation across the population. Corresponding linear and angular measurements quantified the morphometric variance identified by the modes. Linear measures were normalized to the radius of the inferior glenoid to account for differences in the scaling of the bones. Five modes captured 89.7% of total shape variation of the glenoid and periarticular anatomy. Apart from size differences (mode 1: 33.0%), acromial anatomy accounted for the largest variation (mode 2: 32.0%). Further modes described variation in glenoid inclination (mode 3: 11.8%), coracoid orientation and size (mode 4: 9.0%), and variation in coracoacromial (CA) morphology (mode 5: 3.1%). The average scapula had a mean acromial tilt of 49 ± 7°, scapular spine angle of 61 ± 6°, the glenoid inclination of 84 ± 4°, coracoid deviation angle of 26 ± 4°, coracoid length of 3.7 ± 0.3 glenoid radii, and a CA base length of 5.6 ± 0.5 radii. In this study, the identified shape modes explain almost all of the variance in scapular anatomy. The acromion exhibited the highest variance of all periarticular anatomic structures of the scapula in relation to the glenoid, which may play a role in many shoulder pathologies.     

切开复位内固定治疗Ideberg Ⅲ型肩胛盂骨折

目的探讨IdebergⅢ型肩胛盂骨折的手术方式及疗效。方法回顾性分析手术治疗IdebergⅢ型肩胛骨骨折患者10例,1例合并肩峰及锁骨外端骨折,1例合并肩峰及肱骨小结节骨折,6例存在肩锁关节的Ⅱ度损伤,2例Ⅲ度损伤。手术入路均为前入路,利用掌骨钢板和/或空心螺钉行切开复位内固定。结果 8例患者获得平均20.1个月随访。对双肩功能均予以Constant评分,根据患肩占正常侧功能的百分比计算,患肩平均分数为(91.9±5)%。加利福尼亚大学洛杉矶分校(university of California at Los Angeles,UCLA)评分(32.5±3.2)分。肩关节前屈度数达(150±21.4)°,外旋度数达(53.8±11.9)°。内旋伸拇指平均可达到T9±3水平。结论经前入路切开复位内固定是治疗IdebergⅢ型肩胛盂骨折的有效方式,结合对合并悬肩复合体损伤的修复,可以取得良好效果,恢复肩关节功能。