Objective: To explore the reduction and support effect of the subchondral screw compression technique for residual or secondary collapse of the lateral tibial plateau during operation.
Methods: Between January 2020 and June 2021, 11 patients with residual or secondary collapse of the lateral tibial plateau during operation were treated with the subchondral screw compression technique. There were 6 males and 5 females, aged 52.3 years old (range, 27-64 years). The fractures were caused by traffic accident in 10 cases and falling from height in 1 case and located at the left knee in 6 cases and the right knee in 5 cases. According to Schatzker classification, there were 5 cases of type Ⅱ fractures, 4 cases of type Ⅲ fractures, and 2 cases of type Ⅴfractures. According to the three columns classification, there were 5 cases of lateral column, 4 cases of lateral column and posterior column, and 2 cases of three columns. The time from injury to operation was 4.5 days (range, 3-7 days). During the follow-up, X-ray films were obtained and the Rasmussen standard was used to evaluate the quality of fracture reduction, meanwhile fracture healing was observed. The medial proximal tibial angle (mPTA), posterior tibial slope angle (pTSA), and articular surface collapse were measured at immediate and 12 months after operation. The knee joint range of motion was evaluated at last follow-up, and the knee joint function was evaluated using the Hospital for Special Surgery (HSS) score.
Results: All operations were successfully completed, with a mean operation time of 71.4 minutes (range, 55-120 minutes), and a mean hospital stay of 8.0 days (range, 5-13 days). The incisions all healed by first intention, without complications such as infection, flap necrosis, or vascular and nerve injury. All patients were followed up 16.5 months on average (range, 12-24 months). X-ray films showed that the fracture reduction score was 14-18 (mean, 16.7) according to Rasmussen score criteria; and 5 cases were rated as excellent and 6 as good. All fractures healed clinically with a mean clinical healing time of 14.9 weeks (range, 12-16 weeks), and there was no complications such as plate or screw loosening. At 12 months after operation, the mPTA and pTSA were (87.5±1.7)° and (6.2±3.1)°, respectively; there was no significant difference when compared to the values at immediate after operation [(87.6±1.8)° and (6.5±3.1)°] ( P>0.05). The articular surface of the tibial plateaus was effectively supported, and it collapsed again by 0-1.0 mm at 12 months, with an average of 0.4 mm. At last follow-up, the knee joint range of motion was 115°-135° (mean, 126.8°) and the HSS score for knee joint function was 87-98 (mean, 93.9). Five patients underwent secondary operation to remove the internal fixator at 12-18 months after operation.
Conclusion: The subchondral screw compression technique is helpful for the reduction of residual or secondary collapse of the lateral tibial plateau during operation, and can provide good support for osteochondral blocks.
目的: 探讨胫骨平台骨折术中采用软骨下螺钉挤压技术对于外侧胫骨平台术中残留或二次塌陷的复位和支撑效果。.
方法: 2020年1月—2021年6月，11例胫骨平台骨折复位内固定术中，应用软骨下螺钉挤压技术辅助复位外侧胫骨平台术中残留或二次塌陷。其中男6例，女5例；年龄27～64岁，平均52.3岁。致伤原因：交通事故伤10例，高处坠落伤1例。骨折侧别：左侧6例，右侧5例。胫骨平台骨折根据Schatzker分型标准：Ⅱ型5例，Ⅲ型4例，Ⅴ型2例；根据三柱分型标准：外侧柱5例，外侧柱+后柱4例，三柱2例。受伤至手术时间3～7 d ，平均4.5 d。随访期间复查X线片，参照Rasmussen标准评估骨折复位情况，观察骨折愈合情况；于术后即刻和12个月时测量胫骨平台内翻角（medial proximal tibial angle，mPTA）、胫骨平台后倾角（posterior tibial slope angle，pTSA）和关节面台阶，评估复位丢失情况。末次随访时，测量患者膝关节活动度，并采用美国特种外科医院（HSS）评分评估膝关节功能。.
结果: 患者手术均顺利完成，手术时间55～120 min，平均71.4 min；住院时间5～13 d，平均8.0 d。术后切口均Ⅰ期愈合，无感染、软组织坏死以及血管、神经损伤等并发症发生。患者均获随访，随访时间12～24个月，平均16.5个月。X线片复查示，骨折复位参照Rasmussen标准评分为14～18分，平均16.7分；其中获优5例、良6例；骨折均达临床愈合，临床愈合时间12～16周，平均14.9周；随访期间无钢板、螺钉松动发生。术后12个月mPTA和pTSA分别为（87.5±1.7）°、（6.2±3.1）°，与术后即刻（87.6±1.8）°、（6.5±3.1）° 相比，差异均无统计学意义（ P>0.05）。患者胫骨平台关节面均得到有效支撑，术后12个月时再次塌陷0～1.0 mm，平均0.4 mm。末次随访时，患者膝关节活动度为115°～135°，平均126.8°；膝关节功能HSS评分为87～98分，平均93.9分。5例于术后12～18个月二次手术取出内固定物。.
结论: 软骨下螺钉挤压技术有助于外侧胫骨平台术中残留或二次塌陷的复位，并且能够对骨软骨骨折块提供良好支撑。.
Keywords: Subchondral screw compression technique; collapse; internal fixation; reduction; tibial plateau fracture.