Rahm Stefan, Camenzind Roland S, Hingsammer Andreas, Lenz Christopher, Bauer David E, Farshad Mazda, Fucentese Sandro F
Orthopaedic Department, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, CH, Switzerland.
BMC Musculoskelet Disord. 2017 Jun 21;18(1):272. doi: 10.1186/s12891-017-1628-8.
There have been conflicting studies published regarding the ability of various total knee arthroplasty (TKA) techniques to correct preoperative deformity. The purpose of this study was to compare the postoperative radiographic alignment in patients with severe preoperative coronal deformity (≥10° varus/valgus) who underwent three different TKA techniques; manual instrumentation (MAN), computer navigated instrumentation (NAV) and patient specific instrumentation (PSI).
Patients, who received a TKA with a preoperative coronal deformity of ≥10° with available radiographs were included in this retrospective study. The groups were: MAN; n = 54, NAV; n = 52 and PSI; n = 53. The mechanical axis (varus / valgus) and the posterior tibial slope were measured and analysed using standing long leg- and lateral radiographs.
The overall mean postoperative varus / valgus deformity was 2.8° (range, 0 to 9.9; SD 2.3) and 2.5° (range, 0 to 14.7; SD 2.3), respectively. The overall outliers (>3°) represented 30.2% (48 /159) of cases and were distributed as followed: MAN group: 31.5%, NAV group: 34.6%, PSI group: 24.4%. No significant statistical differences were found between these groups. The distribution of the severe outliers (>5°) was 14.8% in the MAN group, 23% in the NAV group and 5.6% in the PSI group. The PSI group had significantly (p = 0.0108) fewer severe outliers compared to the NAV group while all other pairs were not statistically significant.
In severe varus / valgus deformity the three surgical techniques demonstrated similar postoperative radiographic alignment. However, in reducing severe outliers (> 5°) and in achieving the planned posterior tibial slope the PSI technique for TKA may be superior to computer navigation and the conventional technique. Further prospective studies are needed to determine which technique is the best regarding reducing outliers in patients with severe preoperative coronal deformity.
关于各种全膝关节置换术（TKA）技术纠正术前畸形的能力，已有相互矛盾的研究发表。本研究的目的是比较接受三种不同TKA技术的严重术前冠状位畸形（≥10°内翻/外翻）患者的术后影像学对线情况；手动器械辅助（MAN）、计算机导航器械辅助（NAV）和患者特异性器械辅助（PSI）。
本回顾性研究纳入了术前冠状位畸形≥10°且有可用X线片的接受TKA的患者。分组如下：MAN组；n = 54，NAV组；n = 52，PSI组；n = 53。使用站立位全下肢和侧位X线片测量并分析机械轴（内翻/外翻）和胫骨后倾。
术后总体平均内翻/外翻畸形分别为2.8°（范围，0至9.9；标准差2.3）和2.5°（范围，0至14.7；标准差2.3）。总体异常值（>3°）占病例的30.2%（48/159），分布如下：MAN组：31.5%，NAV组：34.6%，PSI组：24.4%。这些组之间未发现显著统计学差异。严重异常值（>5°）的分布在MAN组为14.8%，NAV组为23%，PSI组为5.6%。与NAV组相比，PSI组的严重异常值明显更少（p = 0.0108），而所有其他组对之间无统计学意义。
在严重内翻/外翻畸形中，三种手术技术显示出相似的术后影像学对线情况。然而，在减少严重异常值（>5°）和实现计划的胫骨后倾方面TKA的PSI技术可能优于计算机导航和传统技术。需要进一步的前瞻性研究来确定哪种技术在减少严重术前冠状位畸形患者的异常值方面是最佳的。
