Short-stemmed arthroplasty with glenoid preoperative planning

Total shoulder arthroplasty implant design, instrumentation, and outcomes continue to evolve; however, accurate glenoid placement remains a challenge especially in cases of glenoid deformity. Knowledge that malpositioning of the glenoid can lead to inferior outcomes and glenoid component loosening has led to the development of patient specific instrumentation (PSI). The ideal PSI system should be consistent, reliable, cost-effective, reusable, and robust enough to withstand applied stress during difficult exposures. In addition, short-stemmed humeral components appear to offer several advantages over the traditional length stems.     

Effect of rotator cuff dysfunction on the initial mechanical stability of cementless glenoid components

The functional outcome of shoulder replacement is related to the condition of the rotator cuff. Rotator cuff disease is a common problem in candidates for total shoulder arthroplasty; this study relates the functional status of the rotator cuff to the initial stability of a cementless glenoid implant. A 3D finite element model of a complete scapula was used to quantify the effect of a dysfunctional rotator cuff in terms of bone-implant interface micromotions when the implant is physiologically loaded shortly after surgery. Four rotator cuff conditions (from fully intact to progressively ruptured rotator cuff tendons) as well as two bone qualities were simulated in a model. Micromotions were significantly larger in the worst modeled cuff dysfunction (i.e. the supraspinatus and infraspinatus tendons were fully dysfunctional). Micromotions were also significantly different between conditions with healthy and poor bone quality. The implant’s initial stability was hardly influenced by a dysfunctional supraspinatus alone. However, when the infraspinatus was also affected, the glenohumeral joint force was displaced to the component’s rim resulting in larger micromotions and instability of the implant.     

Arthroscopic reconstruction of chronic anteroinferior glenoid defect using an autologous tricortical iliac crest bone grafting technique

Only a few reports exist on the management of severe anteroinferior glenoid defects in case of recurrent shoulder instability most of them including open approaches. We describe an all-arthroscopic reconstruction technique of the anteroinferior glenoid that includes an autologous iliac crest bone grafting using bio-compression screws and a capsulolabral repair using suture anchors. This technique recreates the bony and soft-tissue anatomy of the anteroinferior glenoid while preserving the integrity of insertion of the subscapularis (SSC) tendon.     

移位的肩胛盂骨折的手术治疗

目的　研究切开复位内固定治疗肩胛盂骨折的效果。方法　将 13例肩胛盂骨折患者按改良的Ideberg分型分类 ,Ⅰ型 2例 ,Ⅱ型 1例 ,Ⅲ型 1例 ,Ⅳ型 9例。Ⅰ、Ⅱ型用标准的三角肌胸大肌入路 ,骨折复位后用 2 7mm拉力螺钉固定。Ⅲ、Ⅳ型用后侧Judet入路 ,骨折复位后用AO重建钢板和螺钉固定。结果　术后随访 6～ 2 4个月 ,平均 14个月。以最后 1次检查结果为准 ,对肩关节的功能进行临床效果评定 :优 7例 ,前屈、外展、上举及内外旋转均较健侧差 10°～ 15°。良 4例 ,外展上举及内外旋转均较健侧差16°～ 3 0° ,前屈后伸正常。可 2例 ,肩关节各方活动、旋转均较健侧差 3 1°～ 60°。结论　开放复位内固定是治疗有移位的肩胛盂骨折的一种较好的方法。     

Techniques to evaluate glenoid bone loss

Assessing glenoid morphology as well as quantifying bone loss is critical when treating patients with recurrent anterior glenohumeral instability because this greatly affects surgeons surgical planning. Although many surgeons agree that 3-dimensionally reconstructed computed tomography (3DCT) images with humeral head digitally subtracted has been considered to be a gold standard when assessing glenoid morphology, there are some surgeons who are making an attempt to replace computed tomography with magnetic resonance imaging to reduce cost for imaging studies and avoid possible radiation exposure, and demonstrated that MRI was equally valuable as 3DCT to quantify glenoid bone loss. However, the role of preoperative imaging study is not only quantifying glenoid bone loss but to assess the glenoid shape and morphology to facilitate surgeons stabilizing the shoulder. In this view, 3DCT is the most recommended preoperative imaging study for bony tissue which provides critical and substantial information of the glenoid.     

Asymptomatic anterior shoulder dislocation of 24-year duration

A 73-year-old woman presented with a very long-standing anterior dislocation of her right shoulder. She had no pain, mild impairment of active shoulder motion and clinical features suggesting no tear of the rotator cuff. CT 3D reconstructions showed a newly formed glenoid cavity below the coracoid process. This case indicates that an anterior shoulder dislocation lasting even decades may be compatible with an almost normal shoulder function.