Adams Brian D, Lawler Ericka A, Kuhl Taften L
Department of Orthopedic Surgery, Baylor College of Medicine, Houston, Texas.
Department of Orthopedics and Rehabilitation, University of Iowa Hospitals and Clinics, Iowa City, Iowa.
J Wrist Surg. 2016 Aug;5(3):217-21. doi: 10.1055/s-0036-1572509. Epub 2016 Feb 19.
Due to a higher risk for implant loosening, particularly of the distal component, patients with physically demanding lifestyles are infrequently considered for total wrist arthroplasty (TWA). A distal radius hemiarthroplasty may obviate the need for the strict restrictions recommended for patients treated by TWA, thus providing another surgical option for active patients with severe wrist arthritis, especially those with articular degeneration of the lunate facet of the radius, capitate head, or combination of both, who are not typically candidates for traditional motion-preserving procedures.
Eight fresh-frozen cadaver limbs (age range, 43-82 years) with no history of rheumatoid arthritis or upper extremity trauma were used. Radiodense markers were inserted in the radius and hand. Posteroanterior (PA) fluoroscopic images with the wrist in neutral, radial deviation, and ulnar deviation, and lateral images with the wrist in neutral, flexion, and extension were obtained for each specimen before implantation, after distal radius hemiarthroplasty, and after combined hemiarthroplasty and PRC.
On the PA images, the capitate remained within 1.42 and 2.21 mm of its native radial-ulnar position following hemiarthroplasty and hemiarthroplasty with PRC, respectively. Lateral images showed the capitate remained within 1.06 mm of its native dorsal-volar position following hemiarthroplasty and within 4.69 mm following hemiarthroplasty with PRC. Following hemiarthroplasty, capitate alignment changed 2.33 and 2.59 mm compared with its native longitudinal alignment on PA and lateral films, respectively. These changes did not reach statistical significance. As expected, significant shortening in longitudinal alignment was seen on both PA and lateral films for hemiarthroplasty with PRC.
A distal radius implant hemiarthroplasty with or without a PRC provides good static alignment of the wrist in a cadaver model and thus supports the concept as potential treatment alternatives for advanced wrist arthritis; however, combined hemiarthroplasty with a PRC has more clinical relevance because it avoids the risk of proximal carpal row instability and eliminates the commonly arthritic radioscaphoid joint.
由于植入物松动风险较高，尤其是远端部件，对于生活方式对身体要求较高的患者，全腕关节置换术（TWA）通常不被考虑。桡骨远端半关节置换术可能无需对TWA治疗的患者进行严格限制，从而为患有严重腕关节炎的活跃患者提供另一种手术选择，特别是那些桡骨月骨面、头状骨头或两者均有关节退变的患者，他们通常不是传统保留运动手术的候选人。
使用8个无类风湿关节炎病史或上肢创伤史的新鲜冷冻尸体上肢（年龄范围43 - 82岁）。在桡骨和手部插入放射性致密标记物。在植入前、桡骨远端半关节置换术后以及半关节置换术联合近排腕骨切除术（PRC）后，为每个标本获取腕关节处于中立位、桡偏和尺偏时的前后位（PA）荧光透视图像，以及腕关节处于中立位、屈曲和伸展时的侧位图像。
在PA图像上，半关节置换术后以及半关节置换术联合PRC后，头状骨分别保持在其原始桡尺位置的1.42和2.21毫米范围内。侧位图像显示，半关节置换术后头状骨保持在其原始背掌位置的1.06毫米范围内，半关节置换术联合PRC后保持在4.69毫米范围内。半关节置换术后，与PA和侧位片上的原始纵向对线相比，头状骨对线分别改变了2.33和2.59毫米。这些变化未达到统计学意义。正如预期的那样，在PA和侧位片上，半关节置换术联合PRC均出现了明显的纵向对线缩短。
在尸体模型中，有或没有PRC的桡骨远端植入半关节置换术均能使腕关节获得良好的静态对线，因此支持将其作为晚期腕关节炎潜在治疗选择的概念；然而，半关节置换术联合PRC具有更大的临床相关性，因为它避免了近排腕骨行不稳定的风险，并消除了常见的放射性舟状骨关节关节炎。
