Abstract:

Objective　To explore anatomic features of L1～5 and S1 vertebrae, and provide parameters for the development of the aliform memory alloy intrasegmental fixation instrument（AMAIFI）.　Methods　20 sets of antiseptic lumbar specimens (L1~5,S1) of Chinese normal adults were used. The distance from the intersection of the lateral margin of the inferior surface of the lumbar spinous process and lamina of vertebra to the superior border of the root segment of transverse process (DITR), the angle between the anterior and posterior sides sitting at the superior border of the root segment of transverse process (AFR), the width of the root segment of transverse process (WRT), the distance from one side of the junction of the transverse process, superior articular process and pedicle of vertebral arch to the another (DTAP), the thickness of the spinous process (TSP), the distance between adjacent spinous process (DAP), the angle between two lines [(ATL), one is the line between the intersection of the lateral margin of the inferior surface of the lumbar spinous process and lamina of vertebra and the junction of the transverse process, superior articular process and pedicle of vertebral arch, another was the lateral margin of the inferior surface of the spinous process], the length of the spinous process (LSP) were measured and analyzed respectively.　Results　Taken L4/L5 as the example: DITR was about (35.30±2.38)mm, AFR (30.47±6.38)°, WRT (11.43±1.76)mm, DTAP (46.44±2.55)mm, TSP (9.04±1.12)mm, DAP (7.10±1.83)mm, ATL (58.31±7.02)°, and LSP (20.40±2.80)mm respectively.     Conclusions　The design of AMAIFI is feasible, which is a safe and convenient device, for mixing together the advantage of the shape memory effects, hyperelasticity and anticorrosion characters of the nickel-titanium shape memory alloy.

Key words: Applied anatomy, Lumbar spondylolysis, Memory alloy, Intrasegmental fixation