头状骨、月骨、三角骨、钩骨测量及四角融合器的设计

目的测量头状骨、月骨、三角骨、钩骨，为研制适于腕骨四角融合术的内固定器械提供解剖学依据，并设计镍钛记忆合金腕骨四角融合器（NiTi shape memory alloy four—comer arthrodesis concentrator，NT—FCAC）。方法解剖45侧成人腕骨标本，保留腕掌、背侧韧带，切除大、小多角骨和手舟骨，游标卡尺测量头状骨、月骨、三角骨、钩骨各骨间距；然后，解剖出上述四腕骨，观察各骨形态，游标卡尺测量各参数；最后，依据测量结果及四腕骨解剖形态特点，结合镍钛记忆合金的特性，设计镍钛记忆合金腕骨四角融合器。结果头月间距最小为（24．75±3．13）mm，钩月间距（29．46±2．85）mm，月三角间距（26．48±2．08）mm；三角骨厚度最小为（8．76±0．91）mm；依据测量结果及镍钛记忆合金的特性，设计出了镍钛记忆合金腕骨四角融合器。结论依据头状骨、月骨、三角骨和钩骨解剖特点及测量结果，结合镍钛记忆合金的特性，能够设计出适于腕骨四角融合术的内固定器械。

Measurements of capitatum lunate triquetrum hamate and design of NiTi shape memory alloy four-corner arthrodesis concentrator

Objective To provide the anatomical proofs for a special internal fixator for four-comer arthrodesis, the anatomic parameters of the four bones （capitatum, lunate, triquetrum and hamate） were measured with vernier caliper. According to the measured results of the four bones and the characteristics of Nitinol, NiTi shape memory alloy four-comer arthrodesis concentrator （NTFCAC） was designed.Methods Firstly, 45 carpal specimens of adult cadaver were anatomized. The ligaments of dorsal and palmar of wrist were preserved. Trapezium, trapezoid and scaphoid were excised. According to the invariable bony marks, the distances between four bones （capitatumlunate, hamate-lunate, lunate-triquetrum, capitatum-triquetrum, hamate-triquetrum and capitatumhamate） were measured with vernier caliper. Secondly, the anatomical shapes of four bones （capitatum, lunate, triquetrum and hamate） were observed after they were separated. Thirdly, the parameters （width, length, thickness） of the four bones were measured with vernier caliper. The plan of NT-FCAC was designed according to the measured datum and anatomic features of the four bones （capitatum, lunate, triquetrum and hamate）, and then a special internal fixator-NiTi shape memory alloy four-comer arthrodesis concentrator （NT-FCAC） was designed with Nitinol. Results The distance of capitate-lunate, hamate-lunate, lunate-triquetrum were （24.75±3.13）mm, （29.46±2.85）mm and （26.48±2.08）mm. The thickness of triquetmm was （8.76±0.91）mm. According to the measured datum of the four bones and the characteristics of Nitinol, NT-FCAC was designed.Conclusion The internal fixation instruments for four-comer arthrodesis can be designed according to the datum and anatomical characteristics of capitatum, lunate, triquetrum and hamate.