Department of Orthopaedic Surgery, Obihiro Kosei Hospital Hand Center, Obihiro, Japan.
Faculty of Dental Medicine, Hokkaido University, N13 W7, Kita-Ku, Sapporo, Hokkaido, 060-8586, Japan.
BMC Musculoskelet Disord. 2022 Aug 30;23(1):821. doi: 10.1186/s12891-022-05776-x.
Although total wrist arthroplasty (TWA) has become a common treatment option for wrists with damage due to rheumatoid arthritis (RA), the optimal implant axial alignment for TWA has been inadequately studied. This study was performed to investigate the relationships between implant alignment and carpal rotational alignment and the wrist range of motion (ROM) following TWA.
This study included 18 patients who underwent TWA using a DARTS® Total Wrist System (Teijin Nakashima Medical, Okayama, Japan) for wrist RA. Pre- and 6-month postoperative computed tomography scans were performed, including the radial volar line (Rv), capitohamate axis (CH), and Rv-CH angle in axial scans. The wrist ROM was also measured. The relationship between the Rv-CH angle and ROM was examined.
The mean Rv-CH angle showed significant wrist pronation from 73.0° to 83.4° postoperatively. We observed a significant positive correlation (0.58) between the postoperative Rv-CH angle and extension and a significant negative correlation (- 0.56) between the postoperative Rv-CH angle and flexion.
Implantation of the DARTS® TWA prosthesis resulted in pronation of the carpal axial alignment, which was correlated with postoperative wrist extension. The volar cortex of the distal radius can be a novel reference axis for adequate implant placement.
尽管全腕关节置换术（TWA）已成为类风湿关节炎（RA）腕关节损伤的常见治疗选择，但 TWA 的最佳植入物轴向对线尚未得到充分研究。本研究旨在探讨 TWA 后植入物对线与腕关节尺偏旋转对线和腕关节活动度（ROM）之间的关系。
本研究纳入了 18 例因腕部 RA 而行 DARTS®全腕关节系统（Teijin Nakashima Medical，日本冈山县）治疗的患者。在术前和术后 6 个月进行了计算机断层扫描，包括轴向扫描中的桡侧掌侧线（Rv）、头状骨 - 月骨轴线（CH）和 Rv-CH 角。还测量了腕关节 ROM。检查了 Rv-CH 角与 ROM 之间的关系。
平均 Rv-CH 角显示术后从 73.0°显著旋前至 83.4°。我们观察到术后 Rv-CH 角与伸展之间存在显著正相关（0.58），与屈曲之间存在显著负相关（-0.56）。
DARTS®TWA 假体的植入导致腕关节尺偏轴向对线旋前，这与术后腕关节伸展有关。桡骨远端掌侧皮质可作为植入物放置的新参考轴。
