Y.-H. Kim, The Joint Replacement Center, Seoul Metropolitan SeoNam Hospital, Seoul, Republic of Korea.
S.-H. Yoon, The Joint Replacement Center, Lee Chun Teck Hospital, Suwon, Seoul, Republic of Korea.
Clin Orthop Relat Res. 2020 Feb;478(2):266-275. doi: 10.1097/CORR.0000000000000916.
Robotic-assisted TKA was introduced to enhance the precision of bone preparation and component alignment with the goal of improving the clinical results and survivorship of TKA. Although numerous reports suggest that bone preparation and knee component alignment may be improved using robotic assistance, no long-term randomized trials of robotic-assisted TKA have shown whether this results in improved clinical function or survivorship of the TKA.
QUESTIONS/PURPOSES: In this randomized trial, we compared robotic-assisted TKA to manual-alignment techniques at long-term follow-up in terms of (1) functional results based on Knee Society, WOMAC, and UCLA Activity scores; (2) numerous radiographic parameters, including component and limb alignment; (3) Kaplan-Meier survivorship; and (4) complications specific to robotic-assistance, including pin-tract infection, peroneal nerve palsy, pin-site fracture, or patellar complications.
This study was a registered prospective, randomized, controlled trial. From January 2002 to February 2008, one surgeon performed 975 robotic-assisted TKAs in 850 patients and 990 conventional TKAs in 849 patients. Among these patients 1406 patients were eligible for participation in this study based on prespecified inclusion criteria. Of those, 100% (1406) patients agreed to participate and were randomized, with 700 patients (750 knees) receiving robotic-assisted TKA and 706 patients (766 knees) receiving conventional TKA. Of those, 96% (674 patients) in the robotic-assisted TKA group and 95% (674 patients) in the conventional TKA group were available for follow-up at a mean of 13 (± 5) years. In both groups, no patient older than 65 years was randomized because we anticipated long-term follow-up. We evaluated 674 patients (724 knees) in each group for clinical and radiographic outcomes, and we examined Kaplan-Meier survivorship for the endpoint of aseptic loosening or revision. Clinical evaluation was performed using the original Knee Society knee score, the WOMAC score, and the UCLA activity score preoperatively and at latest follow-up visit. We also assessed loosening (defined as change in the position of the components) using plain radiographs, osteolysis using CT scans at the latest follow-up visit, and component, and limb alignment on mechanical axis radiographs. To minimize the chance of type-2 error and increase the power of our study, we assumed the difference in the Knee Society score to be 25 points to match the MCID of the Knee Society score with a SD of 5; to be able to detect a difference of this size, we calculated that a total of 628 patients would be needed in each group in order to achieve 80% power at the α = 0.05 level.
Clinical parameters at the latest follow-up including the Knee Society knee scores (93 ± 5 points in the robotic-assisted TKA group versus 92 ± 6 points in the conventional TKA group [95% confidence interval 90 to 98]; p = 0.321) and Knee Society knee function scores (83 ± 7 points in the robotic-assisted TKA group versus 85 ± 6 points in the conventional TKA group [95% CI 75 to 88]; p = 0.992), WOMAC scores (18 ± 14 points in the robotic-assisted TKA group versus 19 ± 15 points in the conventional TKA group [95% CI 16 to 22]; p = 0.981), range of knee motion (125 ± 6° in the robotic-assisted TKA group versus 128 ± 7° in the conventional TKA group [95% CI 121 to 135]; p = 0.321), and UCLA patient activity scores (7 points versus 7 points in each group [95% CI 5 to 10]; p = 1.000) were not different between the two groups at a mean of 13 years' follow-up. Radiographic parameters such as the femorotibial angle (mean 2° ± 2° valgus in the robotic-assisted TKA group versus 3° ± 3° valgus in the conventional TKA group [95% CI 1 to 5]; p = 0.897), femoral component position (coronal plane: mean 98° in the robotic-assisted TKA group versus 97° in the conventional TKA group [95% CI 96 to 99]; p = 0.953; sagittal plane: mean 3° in the robotic-assisted TKA group versus 2° in the conventional TKA group [95% CI 1 to 4]; p = 0.612) and tibial component position (coronal plane: mean 90° in the robotic-assisted TKA group versus 89° in the conventional TKA group [95% CI 87 to 92]; p = 0.721; sagittal plane: 87° in the robotic-assisted TKA group versus 86° in the conventional TKA group [95% CI 84 to 89]; p = 0.792), joint line (16 mm in the robotic-assisted TKA group versus 16 mm in the conventional TKA group [95% CI 14 to 18]; p = 0.512), and posterior femoral condylar offset (24 mm in the robotic-assisted TKA group versus 24 mm in the conventional TKA group [95% CI 21 to 27 ]; p = 0.817) also were not different between the two groups (p > 0.05). The aseptic loosening rate was 2% in each group, and this was not different between the two groups. With the endpoint of revision or aseptic loosening of the components, Kaplan-Meier survivorship of the TKA components was 98% in both groups (95% CI 94 to 100) at 15 years (p = 0.972). There were no between-group differences in terms of the frequency with which complications occurred. In all, 0.6% of knees (four) in each group had a superficial infection, and they were treated with intravenous antibiotics for 2 weeks [corrected]. No deep infection occurred in these knees. In the conventional TKA group, 0.6% of knees (four) had motion limitation (< 60°) [corrected].
At a minimum follow-up of 10 years, we found no differences between robotic-assisted TKA and conventional TKA in terms of functional outcome scores, aseptic loosening, overall survivorship, and complications. Considering the additional time and expense associated with robotic-assisted TKA, we cannot recommend its widespread use.
Level I, therapeutic study.
机器人辅助全膝关节置换术（TKA）的引入旨在提高骨准备和组件对线的精确性，以期改善 TKA 的临床结果和生存率。虽然许多报告表明，使用机器人辅助可以改善骨准备和膝关节组件对线，但没有长期的随机临床试验表明这是否会改善 TKA 的临床功能或生存率。
问题/目的：在这项随机试验中，我们在长期随访中比较了机器人辅助 TKA 与手动对准技术，比较的内容包括：（1）基于膝关节协会（Knee Society）、WOMAC 和 UCLA 活动评分的功能结果；（2）许多影像学参数，包括组件和肢体对线；（3）Kaplan-Meier 生存率；（4）与机器人辅助相关的特定并发症，包括针道感染、腓总神经麻痹、针道骨折或髌骨并发症。
本研究为已注册的前瞻性、随机、对照试验。从 2002 年 1 月至 2008 年 2 月，一位外科医生为 850 名患者中的 975 例机器人辅助 TKA 和 849 名患者中的 990 例常规 TKA 进行了手术。在这些患者中，根据预设的纳入标准，有 1406 例患者符合参与本研究的条件。其中，100%（1406 例）患者同意参与并被随机分组，其中 700 例（750 膝）接受机器人辅助 TKA，706 例（766 膝）接受常规 TKA。其中，机器人辅助 TKA 组 96%（674 例）和常规 TKA 组 95%（674 例）的患者在平均 13（±5）年的时间内可进行随访。在两组中，由于我们预计会进行长期随访，所以没有随机选择年龄大于 65 岁的患者。我们对每组 674 例患者（724 膝）进行了临床和影像学结局评估，并对以无菌性松动或翻修为终点的 Kaplan-Meier 生存率进行了检测。临床评估采用原始膝关节协会膝关节评分、WOMAC 评分和 UCLA 活动评分进行，评估时间为术前和最近的随访。我们还使用平片评估松动（定义为组件位置的变化）、在最近的随访时使用 CT 扫描评估骨溶解、以及在机械轴射线片上评估组件和肢体对线。为了最大程度地降低Ⅱ类错误的可能性并提高我们研究的效能，我们假设 Knee Society 评分的差异为 25 分，以匹配 Knee Society 评分的 MCID，标准差为 5；为了能够检测到这种大小的差异，我们计算需要每组总共 628 例患者，以便在α=0.05 水平达到 80%的效能。
包括膝关节协会膝关节评分（机器人辅助 TKA 组为 93±5 分，常规 TKA 组为 92±6 分[95%置信区间 90 至 98]；p=0.321）和膝关节协会膝关节功能评分（机器人辅助 TKA 组为 83±7 分，常规 TKA 组为 85±6 分[95%置信区间 75 至 88]；p=0.992）、WOMAC 评分（机器人辅助 TKA 组为 18±14 分，常规 TKA 组为 19±15 分[95%置信区间 16 至 22]；p=0.981）、膝关节活动度（机器人辅助 TKA 组为 125±6°，常规 TKA 组为 128±7°[95%置信区间 121 至 135]；p=0.321）和 UCLA 患者活动评分（每组为 7 分[95%置信区间 5 至 10]；p=1.000）在 13 年的平均随访中两组间没有差异。影像学参数，如股胫角（机器人辅助 TKA 组平均 2°±2°外翻，常规 TKA 组平均 3°±3°外翻[95%置信区间 1 至 5]；p=0.897）、股骨组件位置（冠状面：机器人辅助 TKA 组平均 98°，常规 TKA 组平均 97°[95%置信区间 96 至 99]；p=0.953；矢状面：机器人辅助 TKA 组平均 3°，常规 TKA 组平均 2°[95%置信区间 1 至 4]；p=0.612）和胫骨组件位置（冠状面：机器人辅助 TKA 组平均 90°，常规 TKA 组平均 89°[95%置信区间 87 至 92]；p=0.721；矢状面：机器人辅助 TKA 组平均 87°，常规 TKA 组平均 86°[95%置信区间 84 至 89]；p=0.792）、关节线（机器人辅助 TKA 组平均 16 毫米，常规 TKA 组平均 16 毫米[95%置信区间 14 至 18]；p=0.512）和股骨后髁外侧偏移（机器人辅助 TKA 组平均 24 毫米，常规 TKA 组平均 24 毫米[95%置信区间 21 至 27]；p=0.817）在两组间也没有差异（p>0.05）。两组的无菌性松动率均为 2%，且两组间无差异。以组件翻修或无菌性松动为终点，两组 TKA 组件的 Kaplan-Meier 生存率均为 98%（95%置信区间 94 至 100），随访时间为 15 年（p=0.972）。两组间并发症发生的频率没有差异。两组中各有 0.6%（4 例）膝关节发生浅表感染，经静脉用抗生素治疗 2 周[校正]。这些膝关节中没有深部感染。在常规 TKA 组中，0.6%（4 例）膝关节活动受限（<60°）[校正]。
在至少 10 年的随访中，我们发现机器人辅助 TKA 与常规 TKA 在功能评分、无菌性松动、总体生存率和并发症方面没有差异。考虑到机器人辅助 TKA 额外的时间和费用，我们不能推荐其广泛使用。
I 级，治疗性研究。
