Department of Orthopedic Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Chin Med J (Engl). 2010 Nov;123(21):2989-94.
Spine surgery using computer-assisted navigation (CAN) has been proven to result in low screw misplacement rates, low incidence of radiation exposure and excellent operative field viewing versus the conventional intraoperative image intensifier (CIII). However, as we know, few previous studies have described the learning curve of CAN in spine surgery.
We performed two consecutive case cohort studies on pedicel screw accuracy and operative time of two spine surgeons with different experience backgrounds, A and B, in one institution during the same period. Lumbar pedicel screw cortical perforation rate and operative time of the same kind of operation using CAN were analyzed and compared using CIII for the two surgeons at initial, 6 months and 12 months of CAN usage.
CAN spine surgery had an overall lower cortical perforation rate and less mean operative time compared with CIII for both surgeon A and B cohorts when total cases of four years were included. It missed being statistically significant, with 3.3% versus 4.7% (P = 0.191) and 125.7 versus 132.3 minutes (P = 0.428) for surgeon A and 3.6% versus 6.4% (P = 0.058), and 183.2 versus 213.2 minutes (P = 0.070) for surgeon B. In an attempt to demonstrate the learning curve, the cases after 6 months of the CAN system in each surgeon's cohort were compared. The perforation rate decreased by 2.4% (P = 0.039) and 4.3% (P = 0.003) and the operative time was reduced by 31.8 minutes (P = 0.002) and 14.4 minutes (P = 0.026) for the CAN groups of surgeons A and B, respectively. When only the cases performed after 12 months using the CAN system were considered, the perforation rate decreased by 3.9% (P = 0.006) and 5.6% (P < 0.001) and the operative time was reduced by 20.9 minutes (P < 0.001) and 40.3 minutes (P < 0.001) for the CAN groups of surgeon A and B, respectively.
In the long run, CAN spine surgery decreased the lumbar screw cortical perforation rate and operative time. The learning curve showed a sharp drop after 6 months of using CAN that plateaued after 12 months; which was demonstrated by both perforation rate and operative time data. Careful analysis of the data showed CAN is especially useful for less experienced surgeon to reduce perforation rate and intraoperative time, although further comparative studies are anticipated.
使用计算机辅助导航（CAN）的脊柱手术已被证明可降低螺钉错位率、降低辐射暴露发生率，并提供优于传统术中影像增强器（CIII）的手术视野。然而，正如我们所知，之前很少有研究描述过脊柱手术中 CAN 的学习曲线。
我们在同一机构内对两名经验背景不同的脊柱外科医生 A 和 B 进行了两项连续的病例队列研究，分别在同一时期使用 CAN 和 CIII 分析和比较了腰椎椎弓根螺钉的准确性和手术时间。
在包括四年总病例数的情况下，CAN 脊柱手术的皮质穿孔率总体低于 CIII，且手术时间也少于 CIII。对于 A 组和 B 组的外科医生来说，CAN 手术的皮质穿孔率分别为 3.3%和 3.6%（P = 0.191），手术时间分别为 125.7 分钟和 183.2 分钟（P = 0.428），CIII 手术的皮质穿孔率分别为 4.7%和 6.4%（P = 0.058），手术时间分别为 132.3 分钟和 213.2 分钟（P = 0.070）。为了试图证明学习曲线，我们比较了每个外科医生队列中使用 CAN 系统 6 个月后的病例。A 组和 B 组的穿孔率分别降低了 2.4%（P = 0.039）和 4.3%（P = 0.003），手术时间分别缩短了 31.8 分钟（P = 0.002）和 14.4 分钟（P = 0.026）。当只考虑使用 CAN 系统 12 个月后进行的病例时，A 组和 B 组的穿孔率分别降低了 3.9%（P = 0.006）和 5.6%（P < 0.001），手术时间分别缩短了 20.9 分钟（P < 0.001）和 40.3 分钟（P < 0.001）。
从长远来看，CAN 脊柱手术降低了腰椎螺钉皮质穿孔率和手术时间。学习曲线表明，使用 CAN 6 个月后，穿孔率和手术时间均出现明显下降，12 个月后趋于平稳。虽然需要进一步的比较研究，但仔细分析数据表明，CAN 特别有助于经验较少的外科医生降低穿孔率和术中时间。
