髓内固定治疗股骨粗隆间骨折中外侧壁的生物力学意义

The biomechanical significance of intramedullary fixation in the treatment of femoral intertrochanteric fracture

目的分析采用髓内固定PFNA治疗股骨粗隆间骨折中外侧壁的生物力学作用,探讨股骨外侧壁的重要性.方法采用9具同侧成人尸体股骨标本均造成AO分型的A1型股骨粗隆间骨折,然后随机分为3组,每组各3具,其中造成股骨外侧壁损伤的设为对照组,采用股骨近端髓内钉(PFNA)固定并外侧壁完整的设为治疗A组,采用PFNA固定并外侧壁损伤的设为治疗B组,所有股骨标本均采用万能材料测试机进行压缩承载试验,记录最大载荷力,同时用游标卡尺测量骨折断端的间距位移及骨折远、近端滑动位移情况.结果治疗A组的最大载荷力最大,其次是治疗B组,三组相互之间比较差异均具有统计学意义(P<0.01).压缩前三组标本的断端间距相互比较均无明显差异(P>0.05);压缩后治疗A组和B组的断端间距位移和滑动位移均明显小于对照组,差异均具有统计学意义(P<0.05),其中治疗A组的断端间距与治疗B组和对照组比较均无明显差异(P>0.05),间距位移与治疗B组比较无明显差异(P>0.05),但滑动位移小于治疗B组,差异具有统计学意义(P<0.05).结论采用PFNA的髓内固定是治疗股骨粗隆间骨折的有效方式,能够坚强固定骨折,并且外侧壁的完整有利于提高髓内固定的承载力及稳定性,值得临床关注.

Obetive To amalype the biomechanical role in Viro of Lareral Femoral rocanteric wall in itetrocateric fracure inmeulary fixation with PFNA and to observe importance of beral femoral trochanteric Wll.Methods 9 aduls femur specimens of intertrochanteric fracure were caused by AO fracure casification of A1 type,they were randomly divided into the control group.the treatment A group and the treatment B group,every group had 3 specimens.The lateral wall of control group ws damaged.The treatment A group and treatment B group were treated by PFNA.and the lteral wall of the treacmen A goup wa good,but the lureral wall of the treatment B group was dumaged.Thuee groups of spec imens were compression load test with universal testing machine.and the maximun carrying capacity was observed.The distance between facture ends.the compression diplaement ditance of fracture ends and the sliding distance of the fracture fragments along the itetrocuntere were meaured with Caliper.Results The mximum carrying apacity of the teatment goup A was the largest.fllowed by the Ireatment group B.There was stistcal significance between the three groups(P<0.01).The displacement of the fracture spacing stump of the three groups before compresion were not signifcant diferences(P>0.05).The compression displacement distance of fracture ends and the siding distance of the fracture fragments along the ittroehuntre of the treatment A goup and treatmeut B group were les than the control group,they were sgnifiant diferences(P<0.05)。The distance between fracture ends of the treatment A group were no dfferences with the treatment B group and the control group(P>0.05),and the compression dipbaement distance of fracture ends of the treatment A group were no difecrence with treatment B group(P>0.05)。but the sliding distance of the fracture fragments along the intetrochanteric of the trament A group were less than the tretment B group,they were significant dffrences(P<0.05).Conelusion Iotraeullay fixation with PFNA is a efective way to treat itertrochantrir fractures,it can firmly fix the fracture end,and the inegity of the lateral wall is conducive to impoving the bearing capacity and sabiliy of inuramedullary fixation。which deserves clinical atention.