Department of Orthopaedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Department of Orthopaedics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Excellence Center in Osteology Research and Training Center (ORTC), Chiang Mai University, Thailand.
Injury. 2021 Apr;52(4):738-746. doi: 10.1016/j.injury.2020.11.022. Epub 2020 Nov 9.
Reduction of the posterior aspect of proximal humerus fracture, such as far-retracted greater tuberosity or posterior articular head split fracture via a deltopectoral or deltoid splitting approach, is difficult and usually needs extensive dissection. The inverted-L anterolateral deltoid flip approach, which is developed from the deltoid splitting approach, accesses the proximal humerus via lateral deltoid flap lifting. This study compared the area and arc of surgical exposure to the proximal humerus of this proposed approach to existing approaches.
Eleven cadaveric specimens were used. Deltopectoral and deltoid splitting approaches were carried out on the right and left shoulder, respectively. Soft tissue was retracted after completion of a surgical approach to expose the proximal humerus, and dot-to-dot marking pins were placed along the border of exposed area. An additional area with a full shoulder rotation was also marked on the deltopectoral side. An inverted-L deltoid flip approach was further carried out on a deltoid splitting side with a posterior extending incision along the acromion process and the deltoid detachment from the acromion process. The additional area of exposure was subsequently marked. All soft tissue around the proximal humerus was taken down, and the glenohumeral joint was disarticulated. Area of exposure and axial images were taken for further processing and measurement.
An average distance of the axillary nerve from the acromion process of the deltoid splitting and the deltopectoral approaches were 49.15 mm and 57.35 mm, respectively (P < 0.05). The average area of exposure of the inverted-L deltoid flip, deltoid-splitting, deltopectoral, and deltopectoral with full rotation approaches were 2729.81mm, 1404.39mm, 1325.41mm, and 2354.78mm, respectively (P < 0.05). Mean arc of exposure lateral to bicipital groove of the inverted-L deltoid flip, deltoid splitting, deltopectoral, and deltopectoral with full rotation approaches were 151.75degrees, 105.02degrees, 61.68°, and 110.64°, respectively (P < 0.05).
The inverted-L anterolateral deltoid flip approach provides the most posterior access to the proximal humerus. However, it requires more soft tissue dissection and awareness of tension on the axillary nerve. This approach could be an alternative for displaced posterior head splits or far-retracted greater tuberosity proximal humerus fractures.
通过三角肌劈开或三角肌劈开入路减少肱骨近端后关节面骨折，如远侧回缩的大结节或后关节头劈裂骨折，较为困难，通常需要广泛的解剖。从三角肌劈开入路发展而来的倒 L 型前外侧三角肌翻转入路通过侧三角肌瓣提起来进入肱骨近端。本研究比较了该入路与现有入路对肱骨近端的手术暴露面积和弧度。
使用 11 具尸体标本。右侧和左侧肩关节分别进行三角肌劈开和三角肌劈开入路。完成手术入路后，软组织被牵开，以暴露肱骨近端，并在暴露区域的边界处放置点到点标记销。在三角肌侧还标记了一个额外的全肩旋转区域。进一步在三角肌劈开侧沿肩峰和三角肌从肩峰分离的后延伸切口进行倒 L 型三角肌翻转入路。随后标记了额外的暴露区域。切除肱骨近端周围的所有软组织，使盂肱关节脱位。对暴露区域进行轴向成像并进一步处理和测量。
三角肌劈开和三角肌劈开入路腋神经距三角肌肩峰的平均距离分别为 49.15mm 和 57.35mm（P<0.05）。倒 L 型三角肌翻转、三角肌劈开、三角肌劈开加全旋、三角肌劈开加全旋入路的暴露面积分别为 2729.81mm、1404.39mm、1325.41mm和 2354.78mm（P<0.05）。倒 L 型三角肌翻转、三角肌劈开、三角肌劈开加全旋、三角肌劈开加全旋入路肱二头肌沟外侧暴露弧的平均弧度分别为 151.75 度、105.02 度、61.68 度和 110.64 度（P<0.05）。
倒 L 型前外侧三角肌翻转入路提供了肱骨近端最靠后的入路。然而，它需要更多的软组织解剖和对腋神经张力的认识。该入路可作为移位后的后头部劈裂或远侧回缩的大结节肱骨近端骨折的替代方法。
