三角纤维软骨复合体损伤后腕关节稳定性的生物力学分析

目的评估实验性创伤致三角纤维软骨复合体（triangular fibrocartilage complex，TFCC）损伤后腕关节稳定性的变化，为不同类型损伤选择不同的手术方法提供生物力学依据。方法取自愿捐赠新鲜成人上肢标本14个，其中2个标本用于测试实验装置和测量技术。使用1NSTRON 8874生物力学测试系统对标本进行扭转试验。根据Palmer关于创伤性TFCC损伤的分类，将12个标本随机分为4组（n=3），先切开背侧关节囊（arthrotomy，ART）检测，然后进行4类实验性创伤：1A类：TFCC中央部撕裂；1B类：TFCC从尺骨茎突止点上撕裂，伴或不伴尺骨茎突骨折；1C类：TFCC远端撕裂，伴尺月韧带和／或尺三角韧带损伤；1D类：TFCC从桡骨附着缘上撕脱，分别测试腕部从屈60°到伸60°（每变化30°测量1次），被动内外旋（0～20°）的扭矩值。将关节切开后测试的扭矩值与各实验组的扭矩值分别进行比较分析。结果1B类损伤仅切断TFCC在尺骨附着点（1B-1）的扭矩值为（0．709±0．134）Nm，仅切开ART的扭矩值为（0．713±0．121）Nm，二者比较差异无统计学意义（P〉0．05）；如合并尺骨茎突骨折（1B-2），扭矩值为（0．409±0．113）Nm，与仅切开ART的扭矩值比较差异有统计学意义（P〈0．05）。1C类损伤在腕关节处于背伸和掌屈45。时扭矩值分别为（0．878±0．184）、（0．988±0.197）Nm，切开ART在背伸和掌屈30～60°时测得的扭矩值分别为（1．510±0．173）、（1，540±0．093）Nm，比较差异有统计学意义（P〈0．05）。1A、1D类损伤和切开背侧关节囊测得的扭矩值比较差异无统计学意义（P〉0．05）。结论TFCC1B-2类损伤和1C类损伤对腕关节的稳定性有影响。

WRIST STABILITY AFTER EXPERIMENTAL TRAUMATIC TRIANGULAR FIBROCARTILAGE COMPLEX LESIONS

OBJECTIVE: To evaluate the changes in stability of the wrist after experimental traumatic triangular fibrocartilage complex (TFCC) lesions, and to provide basic theoretical criteria for clinical treatment. METHODS: Fourteen adult cadaver upper extremities specimens were included. Two of 14 specimens were tested in pre-experiment. The specimens were tested in a INSTRON 8874 biomechanics measuring instrument. First a dorsal arthrotomy (ART) was performed, and second test was with 1 of 4 different experimental lesions according to Palmer's classification of traumatic TFCC lesions (n=3). 1A: central perforation; 1B: ulnar avulsion with or without fracture of processus styloideus ulnae; 1C: distal avulsion with ligament injury; 1D: radial avulsion. Forced internal external rotation torque were recorded in the interval -60 degrees to 60 degrees of flexion. RESULTS: The average torque of the dorsal ART was (0.713 +/- 0.121) Nm, and the 1B-1 lesion (ulnar avulsion without ulnar styloid fracture) was (0.709 +/- 0.134) Nm, the 1B-2 lesion (ulnar avulsion with ulnar styloid fracture) was (0.409 +/- 0.113) Nm. The difference between the 1B-1 lesion and the dorsal ART was not significant but the difference between the 1B-2 lesion and the dorsal ART was significant (P < 0.05). The average torque of the 1C lesion in about 45 degrees of wrist extention and flexion were (0.878 +/- 0.184) Nm and (0.988 +/- 0.197) Nm, and the dorsal ART were (1.510 +/- 0.173) Nm and (1.540 +/- 0.093) Nm. The difference between the two groups was significant (P < 0.05). The 1A lesion and 1D lesion did not alter significantly wrist stability. CONCLUSION: The 1B-2 lesion and 1C lesion alter significantly the stability of the wrist.