Abstract The fracture of the prosthetic stem after prosthetic replacement of femoral head is not rare. In this study, the photoeastic instrument was used to study the stress distribution on the prosthetic stem following its insertion and to analyse the factors influencing the fracture of the stem. Through the examination of 9 places in 8 cases, it was found that:(1) The removal of femoral calcar and the inframedullary filling of the bone cement directly influenced the stress distribution. (2) The valgus or varus condition of the prosthesis would lead to stress concentration on the stem. (3) Once lossening of the prosthesis occured it would change the preliminary installingstress distribution in the upper femur which would lead to fatigue fracture. Ths experimental data and clinical observation would provide scientific basis forthe prevention of fracture of prosthetic stem following prosthetic replacement of femoral head.
Objective To explore a new method of treating early avascular necrosis of femoral head (AVNFH). Methods Sixty-nine New Zealand adult rabbitswith a mean weight of 2.8 kg after AVNFH presenting were randomly divided into three groups. In group A, deproteinized bone(DPB) combined with the recombinant plasmid pcDNA3.1/vascular endothelial growth factor 165(VEGF165) was implanted in the drilled channel of the necrotic femoral head. In group B, only DPB was implanted. In group C, channel was drilled without DPB or plasmid implanted. Femoral head specimens were obtained 3 days, 1, 2, 4, 8 and 16 weeks after operation. The expression of VEGF165 was examined by RT-PCR, Western blot and immunohistochemical techniques. X-ray testedbone formation generally. Angiogenesis and repair of the femoral head were observed by histological and histomorphometric analysis. Results In group A, the expressions of VEGF165 mRNA and protein were detected 3 days postoperatively, reached apex 1 week and lasted more than 3 weeks after implantation. The ratios of IOD of collagen type Ⅰ were 0.29±0.11, 0.55±0.13 and 0.67±0.10 IOD/μm2 respectively at 2, 4 and 8 weeks postoperatively and the ratios of IOD of new capillary vessels were 0.33±0.10and 0.57±0.16 IOD/μm2 respectively at 2, 4 weeks postoperatively in group A, showing statistically significant difference (Plt;0.01) when compared with groups B and D. X-ray test indicated much bone callus formed early. Conclusion Transfection of the VEGF165 gene can enhance local angiogenesis at early stage andDPBVEGF165 compound can improve bone formation. Deproteinized bone combined with VEGF165 gene provides a potential method for therapy of osteonecrosis.
Objective To study the effect of surgical treatment with core depression and allo-fibular grafting on osteonecrosis of the femoral head in early stages. Methods From June 1998 to August 2004, 22patients with necrosis of the femoral head (39 hips) were treated with core depression and allo-fibular grafting, indluding 17 males and 5 females. Necrosis was classified as Stages Ⅰ-Ⅲ according to ARCO classification system. Their ages ranged from 22 to 60 years and pain duration was 2 to 12 months preoperatively (6.5 months on average). The regular examinations of joint function, X-ray, ECT,CT and MRI were conducted before surgerg and after 15 days, 3 months, and 6 months of surgery. Results All patients were followed up for 3 to 74 months (31.4 months on average). Symptoms 17 of the patients were relievedevidently. Harris hip score from 78 points preoperatively to 91.6 points.The X-ray films 18 of the patients showed that the geography of the hip joint kept intact with no deterioration. Osteogenesis was observed by regular examinations. Two cases (4 hips, 10.25%) were revised by total hip replacement, and 3 cases (4hips, 10.25%) without THR worsened postoperatively. Conclusion The method is less traumatic than common procedures. The joint function can berecovered within 2.4 weeks. Clinical symptoms are greatly improved. This method is effective at least in short term and the long-term effect needs further study.
Abstract To understand the femoral head activity in old fracture of femoral neck, 159 cases from 1982 to 1994 were observed through X-ray film, pathological sections, transparent electronic microscope, tetracycline label technique and ECT examination. The results showed that under a status without stress, the avascular femoral head tended to be repaired in its natural way. The collapse of femoral head was caused by stress to some extent duringthe active repair process. Great attention should be paid in treating fracture of femoral neck that load should never be put on the femoral head during the process of fracture healing.
Objective To compare the effects and indications of total hip replacement(THR) and transplantation of vascularized bone graft in treating late ischemic necrosis of the femoral head.Methods From March 1986 to March 1993, 81 patients with late ischemic necrosis underwent treatment. Of 81 patients, 59 patients who suffered in unilateral hip were divided into 2 groups: 26 underwent total hip replacement and 33 underwent transplantation of vascularized bone graft. There was no significant difference in the Harris-scores of the two groups before operations (Pgt;0.05). The Harris hip scores were compared between different ages(＜30 years, 31.50 years, and ＞51 years) in two groups. Results The follow-up ranged from 10 years and 3 months to 16 years and 5 months (15 years and two months on average). The changes of Harrisscores of the two groups after operations had significant difference in initial stage（Plt;0.05）,but had no significant difference in the long term（Pgt;0.05）. The change of Harris-scores of patients who underwent total hip replacement had no significant difference between different ages （Pgt;0.05），but that of patients who underwent transplantation of vascularized bone graft had significant difference between different ages（Plt;0.05）. Both groupshad satisfactory effects in treating late ischemic necrosis of the femoral head. Conclusion Both methods are effective in treating late ischemic necrosis of the femoral head. Total hip replacement can be more effective insenior patients. Transplantation of vascularized bone can be more effective in young patients.
Objective To investigate diagnosis and surgical management of femoral head osteonecrosis in sickle cell disease(SCD). Methods The related literature available today was reviewed, and the clinical advance in the diagnosis of femoral head osteonecrosis complicating SCD and its surgical management was evaluated. Results Although the advance in the diagnosisand the surgical treatment for the femoral head osteonecrosis in SCD had been achieved, challenging clinical problems still remained because of many complications after the surgical treatment. Whether the surgical management was reasonablein a particular stage of the disease and for a specific patient still required investigation. Conclusion Whether the salvage of the patient’ship joint should be performed or the artificial joint replacement should be performed still needs a cautious consideration before either of the surgical managements is given.
Objective To evaluate the effect of the treatment of necrosis of femoral head with the free vascularized fibula grafting. Methods From October 2000 to February 2002, 31 hips in 26 patients with ischemic necrosis of the femoral head were treated with free vascularized fibula graft. Among these patients, 21 patients (25 hips) were followed up for 6-18 months(12 months on average). According to Steinberg stage:Ⅱ period, 5 hips;Ⅲ period,8 hips; Ⅳ period, 12 hips.Results Among 25hips, their Harris Hip Score at all satges were improved during the follow-up. The symptom of pain diminished or disappeared after operation. The patient’s ability to work and live was notlimited or only slightly limited during the follow-up. Radiographic evaluation showed that most femoral heads improved (18 hips) or unchanged (6 hips) and only oneworsened.Conclusion The free vascularized fibular grafting is a valuable method for femoral head necrosis. With this method, we can prevent or delay the process of the disease.
Objective To investigate the therapeutic effects of the vacularized iliac graft for ischemic necrosis of the femoral head in Niger young patients with sickle cell disease. Methods From November 1998 to Apirl 2001, 12 patients (5 males and 7 females, aging 11-22 years) with sickle cell disease suffered from ischemic necrosis of the femora! head in 14 hips. The lesion was on one hip in 10 patients and on bilateral hip in 2 patients. Necrosis was classified as Ficat Stage Ⅲ-Ⅳ in all patients. Twelve hips in 12...
Objective To evaluate the surgical technique, clinical results, and the complications of modified free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head. Methods From October 2000 to August 2004, 124 patients (139 hips) with osteonecrosis of the femoral head were treated with modified free vascularized fibular grafting. There were 83 males(93 hips) and 41 females (46 hips), with a mean age of 36.4 years(16.57). The disease was caused by trauma in 49 cases(54 hips), use of steroids in 29 cases (32 hips), consumption of alcohol in 19 cases (21 hips) and idiopathic condition in 27 cases (32 hips). Of 139 hips, 50 were classified as stage Ⅱ; 71 as stage Ⅲ, 18 as stage Ⅳ according to Steinberg system; theHarris hip scores were 79.3, 69.3 and 58.4, respectively. At the operation, modified technique of the fibular osteotomy was adopted. A front-hip operative approach was designed and a modified technique of removing the necrotic bone in femoral head was applied. During operation, the duration of operation, the bleeding volume, and the length of incisions were recorded. The follow-up items included the results of X-ray examination, the Harris score of the hip, and the evaluation of the complications. Results The duration of the fibular osteotomy was 10 to 30 min(15 min on average). The duration of the total operation was 80 to 120 min (90 min on average). The length of incision at the hip was 6 to 12 cm (8 cm on average). The bleeding volume was 100 to 300 ml(200 ml onaverage). The average hospitalization days was 7 days. After operation, Harris hip scores in most cases were improved. According to postoperative X-ray, 62 hips (79.5%) were improved to different extents and 14 hips (17.9%) had no significant changes. Deterioration occurred in 2 hips (2.6%). Conclusion The modified free vascularized fibular grafting has lots of virtues, such asless bleeding volume, more clear anatomic structure, more convenience for operation, less damage, less complications, and better results of function recovery.It is an effective method for treating osteonecrosis of the femoral head.
Objective To evaluate the effect of nano-hydroxyapatit e collagen (nHAC) bone and marrow mesenchymal stem cells (MSCs) on the treatment of rabbit osteonecrosis of the femoral head (ONFH) defect. Methods From June to October 2004, animal models of ONFH defect were established i n 45 New Zealand rabbits. They were divided into 3 groups randomly:In group A, as the control group, defect was not filled with any implants; In group B with nHAC; In group C with nHAC+MSC. Imaging and histological observation were made 4, 8, 12 weeks after operation. Results group C had a better o steogenesis ability than group B and group A. group B had a better osteogenesis ability than group A. Obvious new bones and osteogenesis were observed in group C 4 weeks after operation. The defect areas in group C were almost repaired 12 weeks after operation. Conclusion nHAC has a better effect of o steoconduction and it is a superior material for repairing bone defect of ONFH a nd of great value in treating ONFH when compounded with MSCs.