Thienthong Kittikun, Boonard Manusak, Boonrod Artit, Chaisiwamongkol Kowit, Sripadungkul Suwitcha
Department of Orthopaedics, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
Orthopedics Center, Bangkok Hospital Udon, Udon Thani, Thailand.
Eur J Orthop Surg Traumatol. 2018 Oct;28(7):1269-1272. doi: 10.1007/s00590-018-2208-9. Epub 2018 Apr 24.
Complications following locking plate fixation in proximal humeral fractures often related to malposition plates and inadequate screw fixation. However, literature did not define the best anatomical reference point for plate positioning. We conducted a study to assess the occurrence of subacromial impingement and screw perforation with two anatomical reference points for proximal humeral plate positioning.
Sixty shoulders of 30 cadavers were dissected, and proximal humeral locking plate was placed in two different levels in the coronal plane of the upper tip of plate: (1) the proximal portion of bicipital groove group and (2) the most prominent of lesser tuberosity group. Subacromial impingement during passive forward elevation and screw perforation were assessed in relation to the plate positioning.
No subacromial impingement during passive motion contacted to the plate in both groups. The calcar screw perforation rate was significantly lower in the proximal portion of the bicipital groove group (2 of 60 specimens, 3.33%) than the most prominent of lesser tuberosity group (52 of 60 specimens, 86.67%). The most proximal screws of the plate were no humeral head perforation in all specimens.
Our study would suggest that two anatomical reference points could be used to be the landmark to avoid the subacromial impingement and the most proximal screw perforation. However, the placement of the locking plate using the proximal portion of bicipital groove reference is better for calcar screw insertion.
肱骨近端骨折锁定钢板固定术后的并发症常与钢板位置不当和螺钉固定不充分有关。然而，文献中未明确钢板定位的最佳解剖参考点。我们进行了一项研究，以评估肱骨近端钢板定位的两个解剖参考点与肩峰下撞击和螺钉穿孔的发生率。
解剖30具尸体的60个肩部，将肱骨近端锁定钢板置于钢板上端冠状面的两个不同水平：（1）肱二头肌沟组近端；（2）小结节最突出组。根据钢板定位评估被动前举时的肩峰下撞击和螺钉穿孔情况。
两组在被动活动时均未出现与钢板接触的肩峰下撞击。肱二头肌沟组近端的距骨螺钉穿孔率（60个标本中有2个，3.33%）显著低于小结节最突出组（60个标本中有52个，86.67%）。钢板最近端的螺钉在所有标本中均未出现肱骨头穿孔。
我们的研究表明，两个解剖参考点可作为避免肩峰下撞击和最近端螺钉穿孔的标志。然而，使用肱二头肌沟近端参考放置锁定钢板更有利于距骨螺钉的插入。
