Schimizzi Aimee, MacLennan Allison, Meier Kristen M, Chia Benjamin, Catalano Louis W, Glickel Steven Z
C.V. Starr Hand Surgery Center, St. Luke's-Roosevelt Hospital, New York, NY 10019, USA.
J Hand Surg Am. 2009 Sep;34(7):1252-5. doi: 10.1016/j.jhsa.2009.04.026.
The extensor digitorum communis (EDC) splitting approach is a direct lateral approach that can provide greater visualization of the proximal radius than the posterolateral approach to the elbow. The purposes of this study were to identify the anatomic relationships of the posterior interosseous nerve (PIN) during the EDC splitting approach to the proximal radius and to determine its safe zone.
A fellowship-trained attending hand surgeon performed the EDC splitting approach on 15 cadaveric arms, exposing the EDC origin from the lateral epicondyle and dissecting distally to expose the supinator muscle. Calipers were used to measure the distance from the PIN to the radiocapitellar joint and to the lateral epicondyle in neutral position, full supination, and full pronation. The depth of the nerve from the most superficial aspect of the EDC was recorded for each cadaver.
The average distances from the radiocapitellar joint to the PIN in neutral, supination, and pronation were 44.5 +/- 7.9, 40.8 +/- 8.1, and 48.2 +/- 7.9 mm, respectively. The average distances from the lateral epicondyle to the PIN in neutral, supination, and pronation were 61.7 +/- 10.9, 57.6 +/- 9.1, and 64.7 +/- 11.5 mm, respectively. The shortest distance measured from the radiocapitellar joint to the PIN in pronation was 29 mm; the shortest distance measured from the lateral epicondyle to the nerve was 42 mm. The average depth of the nerve from the most superficial aspect of the EDC was 10.2 +/- 2.4 mm.
The PIN is generally safe when dissecting up to 29 mm from the radiocapitellar joint and up to 42 mm from the lateral epicondyle with the forearm in pronation.
指总伸肌（EDC）劈开入路是一种直接外侧入路，与肘关节后外侧入路相比，它能提供更好的桡骨近端视野。本研究的目的是确定在EDC劈开入路至桡骨近端过程中骨间后神经（PIN）的解剖关系，并确定其安全区域。
一位接受过专科培训的手外科主治医生对15具尸体手臂进行EDC劈开入路，暴露EDC起自外侧髁的部位，并向远端解剖以暴露旋后肌。使用卡尺测量在中立位、完全旋后位和完全旋前位时PIN到桡骨头关节以及到外侧髁的距离。记录每具尸体中神经从EDC最浅表层面起的深度。
在中立位、旋后位和旋前位时，从桡骨头关节到PIN的平均距离分别为44.5±7.9、40.8±8.1和48.2±7.9毫米。在中立位、旋后位和旋前位时，从外侧髁到PIN的平均距离分别为61.7±10.9、57.6±9.1和64.7±11.5毫米。在旋前位时从桡骨头关节到PIN测量的最短距离为29毫米；从外侧髁到神经测量的最短距离为42毫米。神经从EDC最浅表层面起的平均深度为10.2±2.4毫米。
当在前臂旋前位时，从桡骨头关节向上解剖29毫米以及从外侧髁向上解剖42毫米时，PIN通常是安全的。
