Objective: To introduce an arthroscopic "inlay" Bristow procedure based on the Mortise-Tenon joint structure concept using suture button fixation, and to evaluate its clinical and radiology results postoperatively with a minimal 3-year follow-up.
Methods: A total of 56 patients who received arthroscopic "inlay" Bristow procedure with suture button fixation between June 2015 to June 2016 were eventually enrolled in this study. Radiological assessment on the 3D CT scan was performed preoperatively, immediately after operation, and postoperatively at the end of 3 months, 6 months and the final follow-up. Complications postoperatively were also recorded.
Results: A total of 56 patients were finally included in this study. The mean follow-up time was (36.1±3.7) months. Coracoid grafts (middle point) were positioned at about 4 o'clock (123.8°±12.3°) in the En-face view. In the axial view, 95% (53/56) of the grafts positioning were measured as flush, 5% (3/56) as medial. Bone union rate was 96.4% at the final follow-up. At the end of 3 months, 6 months, and the final follow-up, the length of the coracoid graft was 96.9%±4.9%, 91.9%±6.2%, and 91.6%±6.6% of the immediate postoperative length, respectively. Compared with the immediate postoperative length, the length measured at the end of 3 months shortened not significantly (t=2.12, P > 0.05). The coracoid graft shortened more pronouncedly 6 months postoperatively (t=4.98, P < 0.05) and then remained almost constant over time (t=-0.75, P > 0.05), with all grafted coracoid graft retaining more than 90% of their initial length by the 3-year follow-up. And new bone formation at the junction between the coracoid graft and glenoid neck in the axial view were obviously noted in 25 cases. The quantitative evaluation showed that the glenoid area in En-face view was significantly increased at the final follow-up than that immediately after surgery [(9.72±1.22) cm2 vs. (9.42±1.11) cm2]. No degenerative changes were noted on CT images in all the patients at the final follow-up.
Conclusion: This study reported a series of "inlay" Bristow procedure with suture button fixation for recurrent shoulder dislocation, providing satisfactory union rate and excellent graft positioning. And using suture button fixation instead of screw can reduce osteolysis and complications related to hardware implantation. Moreover, the bone remodeling between the coracoid process and glenoid could be beneficial to restoring the anterior stability of shoulder joint in a long term follow-up.
目的: 探讨一种基于榫卯结构的改良关节镜下“嵌入式”喙突移位术结合线袢固定的手术方法，并对其术后影像学结果进行分析。
方法: 2015年6月至2016年6月共有56例复发性肩关节前向不稳患者接受了结合线袢固定的关节镜下“嵌入式”喙突移位手术，所有的患者均在术前及术后即刻、3个月、6个月、3年分别进行头盂分离的三维CT评估，评估内容包括骨块位置、骨愈合以及骨重塑情况，并对术后并发症进行随访和记录。
结果: 56例患者平均随访时间为(36.1±3.7)个月。在三维CT扫描En-Face相上喙突骨块中点位于4点钟左右位置(123.8°±12.3°)，CT轴位上喙突骨块位置优良率达到95%(53/56)，3年随访喙突骨块愈合率达到96.4%(54/56)。术后3个月、6个月及3年喙突骨块的长度分别为术后即刻长度的96.9%±4.9%、91.9%±6.2%、91.6%±6.6%，移植喙突骨块在术后3个月时长度变化并不明显(t=2.12，P > 0.05)，而术后6个月时缩短较为明显(t=4.98，P < 0.05)，然后随着时间的推移几乎保持不变(t=-0.75，P > 0.05)，在3年随访时所有移植的喙突骨块都保留了90%以上的初始长度。愈合的病例中未发现明显的骨块吸收；其中25例在CT上都观察到了明显的喙突骨块与关节盂之间的新生骨重塑，术后3年随访时关节盂面积平均为(9.72±1.22) cm2，较术后即刻的(9.42±1.11) cm2有显著增加(P < 0.05)；最终随访时，所有的病例在CT上均未发现骨性关节炎的发生。
结论: 结合线袢固定的关节镜下“嵌入式”喙突移位手术用于治疗复发性肩关节前脱位，术后喙突骨块位置良好、骨愈合率满意。基于榫卯结构以及线袢固定的方法可以提高稳定性，并促进喙突骨块的术后愈合，同时又可以避免使用传统螺钉固定造成的骨溶解以及螺钉植入相关的并发症。更重要的是，术后喙突骨块和关节盂之间的骨重塑显著增加了关节盂面积，有利于恢复肩关节的前向稳定性。
Keywords: Arthroscopy; Joint instability; Shoulder dislocation; Suture button; Three dimensional CT imaging.