Department of Orthopaedic Surgery, Peking Union Medical College Hospital,Chinese Academy of Medical Sciences(CAMS), Beijing, China.
Orthop Surg. 2021 Feb;13(1):145-152. doi: 10.1111/os.12854. Epub 2020 Dec 10.
To examine the accuracy, reliability, and reproducibility of a simple preoperative planning technique using plain X-rays.
A retrospective analysis of 96 consecutive cases of primary direct anterior approach (DAA)-total hip arthroplasty (THA) from July 2015 to December 2018 was performed. The 96 patients included 24 males and 72 females, with an average age of 70 years. The standard AP pelvis radiographs with the patients' hips extended and internally rotated were obtained pre- and postoperatively. The preoperative planning was also completed on the standardized AP pelvic radiographs. The prearranged cup positioning was radiologically measured intraoperatively using fluoroscopy. The correct leg length was assessed intraoperatively, which was compared with the preoperative planning. The component positioning was measured by three independent researchers. Two of the researchers completed the measurements three times, and intra-observer and inter-observer reliability were calculated. All patients received at least 6 months follow-up (6 months-4 years).
In all cases, the median leg length discrepancy (LLD) was 4.4 mm (range 1.6-15.9 mm), and 84 patients had an LLD smaller than 10 mm, of which 58 patients had an LLD of less than 5 mm. None of the patients had a critical LLD of 2 cm or larger. The multivariable logistic regression for LLD (safe range: yes/no) with the co-variables including gender, ASA classification, type of cup, the surgeon's experience level, and the presence of a total hip arthroplasty (THA) on the contralateral side did not present statistical significance. The median angle of the inclination of the acetabular component (IA) was 42.3° (range: 28.7°-52.2°). Ninety-one patients were within the defined safe range. The hit ratio for the cup to be within the safe zone was significantly higher for the Pinnacle cups than that for the Continuum cups (P < 0.05). However, there was no significant difference in gender, ASA classification, the surgeon's experience level, and the presence of a total hip arthroplasty (THA) on the contralateral side. The median of its anteversion (AA) was 20.6° (range: 10.6°-40.1°). Only 41 patients were within the defined safe range. None of the co-variables presented a statistical significance affecting the AA of the cup positioning. Meanwhile, the average fluoroscopy time for the cup positioning (n = 86, missing data in 10 cases) was 4 seconds (range: 1-74), with most of the patients (97.9%) having a fluoroscopy time of fewer than 20 seconds.
The combination of correct preoperative planning and standardized intraoperative measurements can reestablish right leg length and assure the correct cup positioning.
研究一种使用普通 X 光片进行术前规划的简单技术的准确性、可靠性和可重复性。
回顾性分析了 2015 年 7 月至 2018 年 12 月期间 96 例初次直接前入路（DAA）-全髋关节置换术（THA）患者的资料。96 例患者中包括 24 例男性和 72 例女性，平均年龄 70 岁。术前和术后均获得髋关节伸展和内旋的标准骨盆正位 X 线片。术前规划也在标准骨盆正位 X 线片上完成。术中使用透视法对预先安排的杯状位置进行放射学测量。术中评估了正确的腿长，并与术前规划进行了比较。由三位独立的研究人员进行了组件定位测量。其中两位研究人员进行了三次测量，计算了组内和组间的可靠性。所有患者均获得至少 6 个月的随访（6 个月至 4 年）。
在所有病例中，中位数下肢长度差异（LLD）为 4.4 毫米（范围 1.6-15.9 毫米），84 例患者的 LLD 小于 10 毫米，其中 58 例患者的 LLD 小于 5 毫米。没有患者的 LLD 临界值为 2 厘米或更大。对包括性别、ASA 分级、杯状类型、外科医生经验水平和对侧全髋关节置换术（THA）存在等协变量的 LLD（安全范围：是/否）进行多变量逻辑回归分析，没有统计学意义。髋臼组件倾斜角（IA）的中位数为 42.3°（范围：28.7°-52.2°）。91 例患者在定义的安全范围内。与 Continuum 杯相比，Pinnacle 杯的杯状位置安全区的命中率明显更高（P<0.05）。然而，性别、ASA 分级、外科医生经验水平和对侧全髋关节置换术（THA）的存在等协变量没有统计学意义。其前倾角（AA）的中位数为 20.6°（范围：10.6°-40.1°）。只有 41 例患者在定义的安全范围内。没有协变量对杯状定位的 AA 有统计学意义的影响。同时，杯状定位的平均透视时间（n=86，10 例缺失数据）为 4 秒（范围：1-74），大多数患者（97.9%）的透视时间少于 20 秒。
正确的术前规划和标准化的术中测量相结合，可以重新建立正确的腿长并确保正确的杯状位置。
