Agel et al reported the results of 20 patients with proximal humerus fractures that were treated with a Polarus nail.35 This implant has options for proximal interlocking in several directions.

• 肱骨顺行髓内钉建议采用肩峰前侧入路。与肩峰外侧入路相比，前测入路能减小肩袖的损伤，前者可能损伤小圆肌和冈下肌的止点。应注意保护腋神经。