自体髂骨解剖性重建髋臼后壁缺损的生物力学与临床研究

Biomechanical and clinical studies of anatomical reconstruction of posterior wall of the acetabulum with self ilium

目的为严重粉碎性与陈旧性髋臼后壁骨折的重建提供一种新方法。方法（1）生物力学研究：从稳定性及头臼应力分布两个方面进行研究。6具成人新鲜骨盆股骨标本左右侧两两对应分为实验组与对照组，造成髋臼缺损模型后，实验组用髋臼三维记忆内固定系统（acetabular three dimensional memory fixation system，ATMFS）解剖性重建缺损髋臼；对照组用钢板螺钉系统重新复位固定髋臼骨块。比较两组加载状态下在经度及纬度方向的位移，分析解剖性髋臼后壁重建的稳定性；利用压敏片计算并比较两组头臼对应面积，髋臼前壁、臼顶、后壁的平均压强与最大压强，分析解剖性髋臼后壁重建后的头臼匹配性。（2）临床研究：髋臼后壁解剖性重建：取与髋臼直径相同的髋臼锉，从髂嵴内缘旋锉形成解剖性弧面，髂嵴外缘相当于臼壁唇缘。将凿取的髂骨块用ATMFS三维锁定修复后壁缺损。2000年1月一2002年6月，共用此法治疗10例男性患者，年龄16～50岁，平均36．4岁，其中新鲜髋臼骨折7例，陈旧性髋臼骨折3例，后者从骨折至重建术的时间为58～251d，平均137．7d。随访平均5．8年（5．2～7．1年）。结果（1）生物力学研究：实验组与对照组相比，重建后的稳定性与头臼匹配性差异无统计学意义。（2）临床研究：全部患者术后x线片未发现骨折有再移位，下床负重时间为1．6个月（1．2～2．1个月）。异位骨化2例，未影响关节功能活动。按照Modifiedd’Aubigneand Postal临床分级标准，优良率93％。结论利用ATMFS进行自体髂骨解剖性髋臼后壁重建具有良好的稳定性及头臼应力分布，临床应用疗效优良，为髋臼后壁严重粉碎与陈旧性骨折的治疗提供了一种新方法。

Objective To design a new method of posterior wall reconstruction for severely corn- minuted and obsolete fracture of the posterior wall of the acetabulum. Methods （ 1 ） Biomechanical study （from two perspectives： the stability and the stress distribution on the femoral head and the acetabu- lure） ： six fresh adult＇ s pelvis and femur specimens were collected and divided into experimental group （ consisted of the left sides） and control group （ consisted of the right sides）. After the defects of the pos- terior wall were made, the defects were anatomically reconstructed with the harvested ilium by acetabular tridimentional memory fixation system （ATMFS） in the experimental group, whereas the acetabular frag- ments were repositioned to the defect sites and fixated by the plates and screws in the control group. Lon- gitudinal and latitudinal displacement, stability of the anatomically reconstructed posterior wall of the ace- tabulum, the fitness of femoral head to the acetabulum after anatomical reconstruction and mean and maxi- mum pressure of anterior wall, posterior and cupule of the acetabulum were analysed and compared. （2） Clinical study： The posterior wall defect on the harvested ilium piece was repaired with 3-directional loc- king of ATMFS in 10 male patients （at age of 16-50 years, mean 36.4 years） from January 2000 to June 2002. There were seven patients with fresh acetabular fractures and three with old acetabular fractures. The period from fracture to reconstruction for the patients with old fractures was 58-251 days （ 137.7 days on average）. The patients were followed up for 5.8 years （ average 5.2-7.1 years）. Results （ 1 ） Biomeehanieal study showed no statisticaldifference upon stability and fitness of femoral head to aeetabu- lum after reconstruction in experimental and control groups. （2） Clinical study： postoperative X-ray film showed no repeated displacement of the fracture and the patients began out-of-bed movement with weight bearing after 1.6 months （1.2-2.1 months）. Heterotopie ossification was found in two patients, with no influence on the joint function. According to the clinical ranking standard of Modified d＇ Aubigne and Postal, the excellence rate was 93 %. Conclusions Anatomical reconstruction of posterior wall of the acetabulum by using self ilium with ATMS has good stability and stress distribution of the femoral head and the reconstructed aeetabulum in clinical application and offers a new method for treatment of severely comminuted and obsolete fracture of posterior wall of acetabulum.