通过对比倒刺型腕关节假体置换前后的腕关节活动度差异，以及假体抗拔出测试，初步评价倒刺型镍钛记忆合金人工全腕关节假体的生物力学特性。

搜集6例正常新鲜人体前臂(南方医科大学解剖教研室提供)。纳入标准：新鲜冰冻成人前臂，腕关节可自由活动；排除标准：腕关节存在骨折、脱位、骨肿瘤等情况的非正常前臂。使用配对t检验对在术前术后Cortex动作捕捉系统中对比腕关节在掌曲、背伸、尺偏、桡偏四个方向上的最大活动度进行比较。在Elector Force高精度生物材料试验系统上对腕关节假体施加拔出力，拔出力以2 N/s递增，直至假体出现2 mm以上的位移，记录假体松动瞬间的拔出力。使用独立样本t检验对桡骨组件和腕骨组件假体松动瞬间拔出力进行比较。

术后腕关节在背伸、尺偏、桡偏的活动度较术前无统计学差异(P>0.05)。术前掌屈方向最大活动度为(75.0±3.5)°，术后掌屈方向最大活动度为(52.6±3.2)°，二者差异有统计学意义(t＝14.69 ，P<0.05)。桡骨组件平均抗拔出力为(164±15)N，腕骨组件抗拔出力平均为(512±38)N，二者差异有统计学意义(t＝－20.859, P<0.05)。

倒刺型记忆合金人工腕关节假体在活动范围、抗拔出方面基本满足生物力学需求，具有应用于临床的潜在价值。

objective To evaluate the biomechanical characteristics of Ni-ti barb wrist prosthesis.

Six cases of normal human fresh forearm were collected (provided by department of anatomy, Southern Medical University). Inclusion criteria: fresh frozen adult forearm; the wrists were free to move. Exclusion criteria: fracture, joint dislocation or bone tumor on the adult forears. In the Cortex motion capture system, the range of motion (ROM) of wrist prosthesis was compared in flexion, extension, ulnar deviation, and radial deviation before and after total wrist arthroplasty (TWA). The data were analysed by paired t test. In the Elector Force high precision biological material test system, the prostheses were loaded with an increasing pull-out force 2 N per second, until the prosthesis displacement was more than 2 mm. The prosthesis loosening pull-out force at the moment was recorded. Independent sample t test was used to compare the pull-out force of the radial component and wrist component .

ROM of wrist prosthesis in extension, ulnar deviation, and radial deviation showed no statistical difference (P>0.05) before and after TWA. For preoperative maximum flexion was (75.0±3.5) °, postoperative maximum flexion was (52.6±3.2) °, which showed significant difference (t=14.69, P<0.05). The pull-out force of radius prosthesis was (164±15) N, and the pull-out force of metacarpal prosthesis was (512±38) N, which was statistically different( t=-20.859, P< 0.05) .

Ni-ti barb wrist prosthesis can basically meet ROM and pull-out resistance of the daily biomechanics demands, which has some potential value of clinical application.