The research on artificial disc replacement to treat lumbar disc disorders has been conducted for more than 40 years in the world and revealed bright prospects for the promising technique. For a long time, discectomy and/or intervertebral fusion have often resulted in severe complications, such as obstinate lower back pain, dislocation and subluxation of lumbar spinal facet joints, intervertebral instability and compensatory degeneration on neighbored spinal facet joints. The research has shown that the disc prosthesis with active ability will reduce the severe complications. The recent literature has reported that the improved design of the disc prosthesis has been used in the treatment of the lumbar disc disorders with excellent and good results in the world. Comparing several designs and forms of disc prosthesis in terms of case selection, complications and results, we have found that the artificial disc replacement with the modular type SB ⅢCharite for lumbar disc disorders is the best.

[Objective]To study the cause of syringomyliasm for decompressionary cervical cord with severe pressed in patients with cervical disc hernia combined or without cervical spondylopathy.[Method]From May 1997 to December 2005,cervical spinal cord decompression had been performed in 46 patients with severe pressed on cervical spinal cord with cervical disc hernia combined or without cervical spondylopathy.They were followed-up with MRI in 3.5 to 8.8 years post-surgery.[Result]Forty-six cases were found that their MRI be showed a high and higher image in T_1W and T_2W post decompression 9 and 27 months in the segement which being pressed in spinal cord center.And the segement of cervical cord has be showen re-largement as the syringoliasm.[Conclusion]Syringoliosm could be formed after decompression for cervical cord severe pressing.

[Objective]To study the evaluation method for total ankle replacement.[Method]According to anterior-posterior and lateral Xray films of ankle joint pre-and postoperatively,the level of osteotomy and method of bone grafting were confirmed and the correct position of total ankle replacement and its complication were evaluated.Forty-six cases of total ankle replacement were followed up 2~8 years and 4 months with average 5 years and 5 months.With author's radiographic evaluation method and Ko-foed's system,results of ankle function were evaluated.[Result]The foot dorsiflexion was 6?~16? and plantoflexion 8?~28?,movement range of foot dorsiflexion and plantoflexion was 14?~38?(average 21.4?).The function results showed excellent(85~100) in 32 ankles,good(75~84) in 9,and poor(60~74) in 2,no failure case.The complication included necrosis of incision border skin of 3 ankles and intraoperative fractures of both melleola of one ankle;no foot inversion and eversion,no radiographic loosenning were seen.[Conclusion]Radiological evaluation is a critical and useful measure to enhance the quality and function of total ankle replacement,to prevent and to early find its complications.

55%)in 3 during postoperation.It were found better in the post-operative gait than in the pre-operative(P

[Objective] To study the change regulatives of BMD(bone mineral density)in after total ankle arthroplasty.[Methods]From Oct.1997 to Dec.2004,the BMD of the subjects were measured to involve in the study.There were 6 cases(5 male,1 female)with an average of 54.4 years old.Their BMD of the subjects was measured by DEX-A(Lunar)at the tibia and talus of the ankle post-arthroplasty in 6 months,12 months,2 years and 3 years postoperatively.All data were saved in computer and all statistical analyses were performed uaing SPSS 8.0 system in personal computer.[Results]The bone trabecula growing into micropore coated of the prosthesis has been showed on radiograth post-surgeryat average period of 1.5 years to 2 years.In the third year itreached bone mass at the distal tibia and talus of the total ankle replacement,which mean BMD 0.854?0.217 at post operative 6 months,BMD 0.975?0.142 at post operative 12 months,BMD 0.956?0.213 at post operative 2 years,and 1.155?0.210 at 3 years(P

[Objective]To investigate the long-term result of total hip replacement with a Ribbed hydroxyapatite-coated proximally femoral stem and cup component.[Method]From June 1999 to May 2002,24 cases (26 hips) with hip joint disease received cementless total hip replacement with a Ribbed hydroxyapatite-coated proximally femoral stem and cup component. There were 14 males and 10 females with the average age of 59.4 years. The disorders included avascular necrosis of the femoral head in 13 cases,femoral neck fractures in 9 cases,hip dysplasia in 2 cases. X-ray scans were recorded at 7~10 days,6 month,and every 1 year after operation respectively. Harris score was evaluated at last follow-up for hip joint function evaluation.[Result]According to Harris evaluation,16 cases (18 hips) received 85-100 points,8 cases (8 hips) received 75-84 points. Mild thigh pain happed in 1 case. Slight bone absorption was found in 1 case. No case needed second revision. Six month-3 year postoperative X-ray showed bone absorption in Gruen zone 5,6 and 2,3 near HA coating in 1 case (1 hip). Bone density increase was found in both cancellous and cortical bone,which revealed good prosthesis-bone fixation.[Conclusion]A Ribbed proximally hydroxyapatite-coated femoral stem and cup implant are able to enhance the initial fixation of implants,to accelerate bone in-growth and osseous fixation of the femoral stem and cup component,to seal the interface between the implant and osseous,and to prevent ingress of polyethylene particles which lead to thigh pain and bone absorption. It has showed good long-term results.

Objective To study the result of total ankle replacement in treating ankle disorders. Methods Total ankle replacement was employed to treat 18 cases (18 ankles) with ankle disorders including ankle osteoarthritis in six, traumatic arthritis in nine, local necrosis of the talus in two and post ankle arthrodesis in one. Results The follow up averaged three years and nine months (1-5 years). The ankle functions were evaluated with Kofoed's system that showed excellent result in 16 cases and good in 2. The foot dorsiflexion was 6?-12? and plantoflexion 8?-16?. Movement range of the foot dorsiflexion and plantoflexion was 11?-23?. The implication was the skin necrosis of incise bordger. No foot inversion, eversion and radiographic loosen were seen. Conclusion Total ankle replacement is a good method for improvement of the ankle function.