Asavamongkolkul Apichat, Waikakul Saranatra
J Med Assoc Thai. 2016 Oct;99(10):1110-8.
Osteoarticular allograft is now commonly used as a reconstructive biomaterial to replace bone defect following removal of aggressive bone tumors and for revision of failed arthroplasty. Good long-term clinical result of allograft replacement has been demonstrated. However, the rate of complications is high, including deep infection, allograft fracture, delayed union or non-union, and joint instability. Prevalence of allograft fracture ranges from 12-54 percent. Many studies recommend avoiding plate and screw fixation, or they advise the use of a modified screw fixation technique that minimizes the number of screws and changes screw alignment.
The objective of this study was to compare the efficacy of the conventional technique with a new method of plate and screw fixation in osteochondral allograft following removal of aggressive bone tumors.
From September 1988 to February 2015, 52 patients with primary aggressive benign or malignant bone tumor underwent massive bone allograft reconstruction. There were 25 males and 27 females with a mean age of 27-years. Giant cell tumor and osteosarcoma comprised most of the diagnoses. Thirty-five of the tumors were located around the knee. Average length of allograft was 12.9 cm. Twenty-nine patients were reconstructed using standard technique and 23 patients were fixed using only one dynamic compression plate with limited and 15-degree divergent-angle screw fixation at the allograft.
Mean follow-up time in the group treated by conventional fixation was 84.5 months. There were 13 fractures (44.8%) in the conventional fixation group, with a median time to graft fracture of 4.9 months. The 23 patients with new technique fixation were followed-up for a mean duration of 60.5 months. Six fractures (26.1%) occurred in this group, with a median time to graft fracture of 10.40 months. Differences between groups for incidence of allograft fracture and median time to fracture were not statistically significant (p = 0.163 and p = 0.244, respectively). Most patients with allograft fracture were treated surgically using autogenous bone grafting and revision of internal fixation.
The new method of osteochondral allograft fixation using single plate, fewer screws, and divergent screw fixation yielded a lower fracture rate and a longer median time to fracture than the conventional method; however the differences between groups did not achieve statistical significance. The results of this preliminary study should be confirmed in a larger group of allografts over a longer follow-up period.
骨关节同种异体移植目前常用于作为一种重建生物材料，以替代侵袭性骨肿瘤切除后的骨缺损以及用于翻修失败的关节成形术。同种异体移植置换已显示出良好的长期临床效果。然而，并发症发生率较高，包括深部感染、同种异体移植骨折、延迟愈合或不愈合以及关节不稳定。同种异体移植骨折的发生率在12%至54%之间。许多研究建议避免使用钢板和螺钉固定，或者建议采用一种改良的螺钉固定技术，尽量减少螺钉数量并改变螺钉排列方向。
本研究的目的是比较传统技术与一种新的钢板和螺钉固定方法在侵袭性骨肿瘤切除后骨软骨同种异体移植中的疗效。
从1988年9月至2015年2月，52例原发性侵袭性良性或恶性骨肿瘤患者接受了大块骨同种异体移植重建。其中男性25例，女性27例，平均年龄27岁。大多数诊断为骨巨细胞瘤和骨肉瘤。35例肿瘤位于膝关节周围。同种异体移植的平均长度为12.9厘米。29例患者采用标准技术重建，23例患者仅使用一块动力加压钢板进行固定，在同种异体移植处采用有限和15度发散角螺钉固定。
传统固定组的平均随访时间为84.5个月。传统固定组发生13例骨折（44.8%），移植骨折的中位时间为4.9个月。采用新技术固定的23例患者平均随访时间为60.5个月。该组发生6例骨折（26.1%），移植骨折的中位时间为10.40个月。两组之间同种异体移植骨折发生率和骨折中位时间的差异无统计学意义（分别为p = 0.163和p = 0.244）。大多数同种异体移植骨折患者采用自体骨移植手术治疗并翻修内固定。
采用单钢板、较少螺钉和发散螺钉固定的骨软骨同种异体移植新方法与传统方法相比，骨折发生率较低，骨折中位时间较长；然而两组之间的差异未达到统计学意义。这项初步研究的结果应在更大规模的同种异体移植组中进行更长时间的随访来加以证实。
