经皮微创钢板内固定技术治疗肱骨中下段骨折的解剖学研究

Anatomical study of the treatment of middle and distal thirds of humeral shaft fractures with MIPPO technique

目的为经皮微创钢板内固定技术（MIPPO）治疗肱骨中下段骨折提供解剖学依据，并探讨其临床应用的可行性。方法解剖4具8侧成人尸体上肢标本，对桡神经与肱骨以及与插入钢板之间的关系进行解剖学分析。结果前方入路插入钢板后，桡神经与钢板之间均存在一薄层肱肌间隔，前臂旋后时钢板外侧缘与桡神经之间的中位距离为3.4 mm（2.2-5.1 mm）。外侧入路时桡神经与前外侧的钢板外侧缘之间的最近中位距离为1.7mm（1.0-2.9 mm）。结论在肱骨中下段经外侧方入路插入钢板和前方入路插入钢板均是可行的，但是相比较而言前方入路更安全、更易操作，钢板无需特殊塑形，而外侧入路钢板过长有损伤桡神经的可能。

Objective To provide anatomical basis for minimally invasive percutaneous plate osteosynthesis （MIPPO） technique in the treatment of middle and distal thirds of humeral shaft fracture and evaluate the safety and clinical feasibility of this technique. Methods This study was performed on 8 upper limbs from 4 fresh cadavers. The anatomical analysis of the relative courses of the radial nerve and humerus was performed and the relationship between the radial nerve and the inserted plate in the forearm in full pronation and in the supination was investigated following the locking compression plate （LCP） insertion with the lateral approach and anterior approach. Results There was no radial nerve entrapment by the plate in any ease. The plate was laid on the anterior surface of the humerus in anterior group and the radial nerve was separated by a thin layer of muscles from the lateral cortex of the distal humerus. The closest distance measured between the lateral border of the plate and the radial nerve in full supination of the forearm was 2.2 - 5.1 mm （median： 3.4 mm）. In lateral group the distance was 1.0 -2.9 mm（ median： 1.7 mm）. When the forearm was pronated the radial nerve was observed to move medially close to the distal end of the plate. Conclusion It is feasible to treat middle and distal thirds of humeral shaft fractures by using the MIPPO technique through the lateral approach and anterior approach, on the grounds that there was no obvious damage. The anterior approach is a better choice when using MIPPO technique in the treatment of humeral distal fractures. The advantage of the anterior approach is as follows： the radial nerve is not at risk as long as the forearm is maintained in supination during the process; and a straight implant can be used without excessive bending or twisting. However, lengthy plate has the possibility of damaging the radial nerve.