胫骨平台后外侧象限骨折手术入路的深层解剖及后外侧与后内侧比较

目的　对比膝关节后内侧与后外侧入路所需显露的深层解剖结构，分析探讨其局限性与损伤重要结构的风险。 方法　5个成人下肢尸体标本，解剖测量胫前动静脉穿过骨间膜上裂孔的位置和腓骨头对胫骨后外侧平台的遮挡面积比例；观察膝关节后外侧入路、后内侧入路需要显露的深层结构。结合解剖研究，临床应用20例，比较两种入路的优缺点。 结果　采用后外侧入路显露胫骨平台后外侧象限，主要有下列3个缺点：(1)胫前血管束向前穿过胫腓骨间膜上裂孔，三根血管纵向宽度在1 cm左右，其前穿点距离关节面和腓骨头最高点距离平均4.93 cm和3.77 cm；其上方伴行静脉，距二者的距离分别是4.41 cm和3.25 cm，影响切口的纵向显露；(2)腓骨头遮盖后外侧象限平均61.7%，阻挡向外的横向显露宽度；(3)显露后外侧关节面，需破坏部分后外侧角结构，包括腘肌肌腱复合体、韧带、关节囊等。 结论　显露孤立的胫骨平台后外侧象限骨折，采用膝关节后内侧入路，可能更为合适。

Surgical exposure to posterolateral quadrant tibial plateau fractures: an anatomic comparison of posterolateral vs posteromedial approaches

Objective　To compare deep anatomical structures of posterolateral and posteromedial approaches, andanalyze the limitations and risk of injury to important structures during surgical dissection.Method　Five lower limb specimens were dissected to measure the perforating level of the anterior tibial artery at the interosseous membrane fissure and the shielding percentage by fibular head to the posterolateral cortex. Clinically, 20 cases were treated via a posterolateralor posteromedial approach. The two approaches were compared with each other.　 Result　The posterolateral approach had three major disadvantages:(1) the width of the anterior vascular bundle was about 1 cm; the distance between the level ofthe anterior tibial artery perforating point and tibial plateau/superior tip of fibular head was 4.93 cm and 3.77 cm, respectively. The distance for the superior concomitant vein was 4.41 cm and 3.25 cm in average, respectively, which limit the incision exposure. (2) The percentage of the posterolateral cortical area shielded by fibular head was 61.7% in average. (3) In order to expose the posterolateral articular surface, partial structure of posterolateral corner was destroyed, including the popliteus tendon complex, ligament and joint capsule, etc.　Conclusion　A posteromedial approach via the medial head of gastrocnemius-soleus maybe more suitable to expose isolated posterolateral quadrant tibial plateau fracture.