青少年特发性脊柱侧凸术后adding-on现象病例分析及分类初探

Cases report of postoperative adding-on phenomenon in patients with adolescent idiopathic scoliosis and a preliminary classification

目的初步探讨青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者术后远端adding-on现象的原因和分类。方法回顾分析在我院行手术矫形、术后随访期发生明显adding-on现象的14例AIS患者。根据其影像学、年龄及骨骼成熟度等参数的不同,将所有adding-on病例分为3种类型:I型为伴有术后双肩失平衡型;II型为伴有术后冠状位失平衡型;III型为不伴有双肩和冠状位失平衡型,并对各类型的临床和影像学特点进行初步总结。结果 I型6例(42.9%),患者术后明显双肩失平衡,平均双肩高度差(radiographic shoulder height,RSH)为20(15~25)mm。术后2年的随访中,RSH减少到6(0~12)mm,但是其远端adding-on角度平均增加14°(5°~23°)。II型3例(21.4%),术后明显冠状位失平衡,平均冠状面失平衡值为45(39~54)mm。末次随访时,冠状位失衡平均减小13(8~17)mm,但adding-on角度平均增加10°(5°~14°)。III型5例(35.7%),所有患者Risser征均为0度,术后即刻无明显双肩和冠状位失平衡,但是随访期中仍然发生adding-on,其adding-on角度平均增加10°(6°~15°)。长期随访结果表明,I型和II型均无再次手术者,但是1例III型患者因侧凸进展迅速接受了再次手术。结论本次研究提出adding-on现象的初步分型,描述其相关临床及影像学特点,将有助于adding-on的发病机制的探讨。

Objective To explore the factors and classification of distal adding-on phenomenon in the patients with adolescent idiopathic scoliosis（ AIS） after correction surgery. Methods Medical records of 14 AIS patients suffering from adding-on phenomenon after surgical therapy in our hospital were retrospectively reviewed. Three different types of adding-on phenomenon were classified according to their various parameters such as image, age, skeletal maturity and so on, and clinical and imaging characteristics of each type were summarized. Addingon phenomenon was divided into 3 subtypes： postoperative shoulder imbalance（ Type I）, postoperative trunk imbalance（ Type II） and neither shoulder nor trunk imbalance after surgery（ Type III）. Results Significant shoulder imbalance was observed in 6 patients（ 42.9%） immediately after surgery who met the criteria of Type I, with the mean radiographic shoulder height（ RSH） of 20 mm（ range： 15- 25 mm）. During the 2-year follow-up, the mean RSH was decreased to 6 mm（ range： 0- 12 mm）. The mean distal adding-on angle was increased by 14°（ range： 5°- 23°）. Three patients（ 21.4%） met the criteria of Type II, and the trunk shift was increased from 39 mm to 54 mm after surgery（ average： 45 mm）. At the final follow-up, the trunk shift was decreased to 13 mm（ range： 8- 17 mm）, while the mean adding-on angle was increased by 10°（ range： 5°- 14°）. Five patients（ 35.7%） who met the criteria of Type III were found well-balanced in both shoulder and trunk after surgery. Risser sign was 0 in all the patients, while their mean adding-on angle was still increased by 10°（ range： 6°- 15°）. Furthermore, no tendency of progressionor re-operation was noticed in the patients with Type I and Type II during the long-term follow-up. However, 1 patient with Type III received re-operation due to rapid progression of scoliosis. Conclusions Three subtypes of adding-on phenomenon are introduced, as well as their clinical and imaging characteristics, which may make us understand the pathogenetic mechanisms more profoundly.