Conaway Danielle A, Kuhl Taften L, Adams Brian D
Department of Orthopaedic Surgery, University of Iowa, Iowa City, IA 52242, USA.
J Hand Surg Am. 2009 Jul-Aug;34(6):1056-62. doi: 10.1016/j.jhsa.2009.03.014.
To assess the match in size and shape between the native ulnar head and a partial ulnar head implant in cadaver specimens.
Ten fresh-frozen cadaver arms (6 male, 4 female, age range 79-91 years) with no history of previous distal radioulnar joint surgery were used. Radiographic measurements before and after implantation were used to compare ulnar head articular height, width, offset, and ulnar variance. Head diameter was measured using photographs of the resected ulnar heads.
The partial ulnar head implant consistently reproduced the natural anatomic size and shape for all variables except ulnar head height and ulnar variance. Head height was greater with the implant, but the additional height extended proximally into the distal radioulnar joint synovial recess, which is unlikely to have adverse affects. Ulnar variance match was technique dependent, with a tendency to place the implant in more neutral variance when positive variance was present before surgery.
Our study demonstrated that a partial ulnar head implant, which replaces the articular surfaces, can closely re-create the ulnar head anatomy. By virtue of restoring the anatomy without an extensive dissection, the clinical results should be expected to at least match the functional results of total head replacement, reduce the rehabilitation, and possibly reduce the risk of joint instability.
评估尸体标本中天然尺骨头与部分尺骨头植入物在尺寸和形状上的匹配情况。
使用10只无既往远端桡尺关节手术史的新鲜冷冻尸体手臂（6例男性，4例女性，年龄范围79 - 91岁）。植入前后的影像学测量用于比较尺骨头关节高度、宽度、偏移和尺骨变异。使用切除的尺骨头照片测量头部直径。
除尺骨头高度和尺骨变异外，部分尺骨头植入物在所有变量上均能持续重现自然解剖尺寸和形状。植入物的头部高度更大，但额外的高度向近端延伸至远端桡尺关节滑膜隐窝，这不太可能产生不利影响。尺骨变异匹配取决于技术，术前存在正变异时，倾向于将植入物置于更中性的变异位置。
我们的研究表明，替代关节面的部分尺骨头植入物可以紧密地重新构建尺骨头解剖结构。通过在不进行广泛解剖的情况下恢复解剖结构，预计临床结果至少能与全头置换的功能结果相匹配，减少康复过程，并可能降低关节不稳定的风险。
