观察应用3D打印截骨导板辅助完成双膝关节同期置换手术(TKA)中的优势，并探讨3D打印技术在膝关节置换手术应用的实际意义。

2014年10月至2015年2月，从沈阳市骨科医院关节外科住院患者中，选取双膝关节骨关节炎患者，行一期双膝关节置换手术。纳入标准包括：确诊膝骨关节炎(KOA)；症状严重影响患者生活质量；KOA分级≥ 3级；60～75岁，无手术禁忌症等。排除类风湿关节炎或创伤性关节炎、近期存在感染或合并严重心脑血管疾病者。共19例患者纳入3D组，在个性化定制3D打印截骨导板辅助下完成双膝关节置换手术，另以随机数字表法选取20例为对照组，行常规工具膝关节置换手术；3D组女15例，男4例；对照组女16例，男4例。两组手术采用相同手术入路，对比观察手术时间、术中出血量、术后引流量、隐性出血量。计量资料符合正态分布的，组间比较采用两独立样本t检验，组内比较采用配对t检验；计数资料行卡方检验。术后采用统一康复方案及用药方案，术后3、6个月进行规范化随访，采用美国膝关节协会(KSS)评分评价膝关节功能康复情况。术后通过摄取标准化正侧位X光片评估股骨和胫骨机械轴的夹角(MFTA)；冠状位股骨解剖轴和股骨髁切线的夹角(LDFA)；冠状位胫骨解剖轴和胫骨平台切线的夹角(MPTA)；矢状位胫骨后倾角(STCA)，行两独立样本t检验对比两组间的差异。

两组在年龄、性别比例上差异均无统计学意义(P>0.05)。手术时间两组间比较3D组(170.6±26.5)min、略长于对照组(165.3±24.7)min，但差异无统计学意义(P>0.05)。术中出血量、术后引流量、隐性出血量3D组均少于对照组，差异有统计学意义(t＝7.1177，7.2297，27.3163，P均< 0.05)。KSS评分术后3个月3D组(92.1±2.3)；对照组(89.4±3.6)，差异有统计学意义(t＝2.7797，P<0.05)。MFTA、STCA两组间比较，差异存在统计学意义(t＝7.1586，3.8190，P均<0.05)；LDFA、MPTA两组间差异无统计学意义(P>0.05)。

相对于常规工具膝关节置换，定制3D打印导板辅助膝关节置换术具有个体化、精准化、数字化、创伤小等优点，可以对膝关节置换，尤其在双膝同期置换中起到良好的辅助作用。

To observe advantages of simultaneous bilateral total knee arthroplasty (TKA) with three-dimentional(3D) printing osteotomy-guiding-plate and to analysis the actual significance of 3D printing technology in total knee arthroplasty.

From October 2014 to February 2015, the patients with osteoarthritis of knee joint were selected from inpatients of joint surgery department in Shenyang Orthopedic Hospital. The inclusion criteria were as follows: diagnosed as knee osteoarthritis(KOA); the symptoms were severe; classification of OA≥stage three; 60-75 years old without contraindication for surgery. Rheumatoid arthritis, traumatic arthritis, infection and cardiac or cerebrovascular diseases were excluded. Nineteen patients underwent bilateral total artificial knee arthroplasty with the help of personalized customized customized 3D printing mold(the 3D group), the other 20 patients who were selected by random number table underwent conventional total knee arthroplasty (the control group). The 3D group included 15 females and four males; the control group included 16 females and four males. The operation time, intraoperative blood loss, amount of post-operation drainage and occult bleeding volume were evaluated and compared between the 3D group and the control group with the same surgical approach. After the surgery, the two groups used the same rehabilitation program and medication regimen. A standardized follow-up was performed at three and six months postoperatively. The American Knee Society knee score(KSS) was used to evaluate the rehabilitation of knee joint function. Normalized lateral radiographs were taken to assess the angle between the femoral and tibial mechanical axes(MFTA), the angle between the anatomical axis of the femur and the tangent line of the femoral condyle in the coronal position(LDFA), the angle between the tibial anatomical axis and the tibial plateau tangent in the coronal position(MPTA), and the tibial posterior tilt angle in the sagittal plane(STCA). The differences between the two groups were compared by t test.

There was no significant difference in age and sex between the two groups, and there was no statistical significance(P>0.05). In the comparison of operation time, the 3D group was (170.6±26.5) min, slightly longer than the control group(165.3±24.6)min, but not statistically significant(P>0.05). In the comparison of intraoperative blood loss(t=7.1177), amount of post-operation drainage(t=7.2297) and occult bleeding volume(t=27.3163), the 3D group were less than the control group, there were significant differences(all P<0.05). Three months after the surgery, the KSS score difference between the two groups was statistically significant: the 3D group was (92.1± 2.3), while the control group was (89.4±3.6)(t=2.7797, P<0.05). There were significant differences between the two groups in the MFTA(t=7.1586) and the STCA(t=3.8190 )(all P<0.05). There was no significant difference between the two groups in the LDFA and the MPTA (P>0.05).

TKA with customized 3D printing osteotomy guides has the advantages of individualization, precision, digitization, and minimal trauma compared with TKA using conventional tools; in particular, the use of customized 3D printing osteotomy guides plays a good supporting role in bilateral simultaneous TKA.