Objective To investigate the causes and preventive methods of the bone cement leakage in percutaneous kyphoplasty (PKP) for osteoporotic vertebral body compression fracture (OVCF). Methods From April 2003 to November 2007, 116 patients with OVCF were treated with PKP, including 57 males and 59 females aged 65-92 years old (average 67.7 years old). All the patients suffered from trauma and the course of disease was 1-14 days (average 5.7 days). There were 159compressed and fractured vertebral bodies, including one vertebral body in 83 cases, two vertebral bodies in 24 cases, three vertebral bodies in 8 cases, and four vertebral bodies in 1 case. The diagnosis of OVCF was confirmed by imaging examination before operation. All the patients had intact posterior vertebral walls, without symptoms of spinal and nerve root injury. During operation, 3.5-7.1 mL bone cement (average 4.8 mL) was injected into single vertebral body. Results The operation time was 30-90 minutes (average 48 minutes). Obvious pain rel ief was achieved in all the patients after operation. X-rays examination 2 days after operation revealed that the injured vertebral bodies were well replaced without further compression and deformation, and the bone cement was evenly distributed. Fourteen vertebral bodies had bone cement leakage (4 of anterior leakage, 4 of lateral leakage, 3 of posterior leakage, 2 of intervertebral leakage, 1 of spinal canal leakage). The reason for the bone cement leakage included the individual ity of patient, the standardization of manipulation and the time of injecting bone cement. During the follow-up period of 12-30 months (average 24 months), all the patients got their normal l ife back, without pain, operation-induced spinal canal stenosis, obvious height loss of injured vertebral bodies and other compl ications. Conclusion For OVCF, PKP is a mini-invasive, effective and safe procedure that provides pain rel ief and stabil ization of spinal stabil ity. The occurrence of bone cement leakages can be reduced by choosing the suitable case, improving the viscosity of bone cement, injecting the proper amount of bone cement and precise location during operation.
Objective Use the method of Cochrane systematic review to evaluate the difference of two fixation methods of femoral component in hip arthroplasty in order to choose the most appropriate fixation method. Methods Searches was applied to the following electronic databases: Chinese Bimedical Database (CBM) (1979 to Dec. 2004), MEDLINE (1966 to Feb. 2005), EMBASE (1984 to 2004) and The Cochrane Library (Issue 4, 2004). We handsearched Chinese Journal of Orthopaedy, the Journal of Bone and Joint Injury and Orthopaedic Journal of China (from establishment to Feb. 2005). Randomized controlled trials (RCT) were indentified and we applied RevMan 4.2 for statistical analysis. Results Nine RCTs involving 1 075 hips were included. The combined results of meta-analysis showed that the embolization occurred more commonly in the first and second generation cemented group (OR 0.02, 95%CI 0 to 0.11, P＜0.000 01), but this difference was not seen between the third generation cemented group and uncemented group (OR 0.80, 95%CI 0.36 to 1.78, P=0.58); The subsidence of femoral component (OR 12.20, 95%CI 3.58 to 41.54, P＜0.000 1) and the cortical hypertrophy (OR 69.97, 95%CI 27.88 to 175.57, P＜0.000 01) were more commonly found in uncemented group; the thigh pain occurrence, the revision for the femoral component’s cause and heterotopic ossification were found no significant difference in the two groups. Conclusions Compared with noncemented group, we found that cemented fixation may be more associated with embolism in the first and second generation cemented technique and less with femoral subsidence and cortical hypertrophy. There was no significant difference in embolization between the third generation cemented technique group and noncemented group. However, more randomized controlled trials to evaluate the occurrence of the postoperative thigh pain, revision and heterotopic ossification are needed.
【Abstract】 Objective To explore the flexibil ity and rel iabil ity of cementless total knee arthroplasty (TKA) without patellareplacement through a retrospective study of the mid-term therapeutic effect of the treatment of the patients. Methods FromJune 1997 to March 2000, a consecutive series of 152 (152 knees) cementless TKA performed in Hessing-Stiftung was studied. Among them, there were 63 males and 89 females, with 70 left knees and 82 right knees. Their ages ranged from 51 years to 72 years, with an average of 59 years. There were 146 cases of osteoarthritis and 6 cases of traumatic arthritis. The course of the disease lasted for 1.0 years to 3.5 years. The EFK prostheses of German Plus company were used in all the cases. The HSS score before the operation was 41.5 ± 12.3, and the average range of motion was 55º (ranging from 30º to 90º). Results Five patients underwent anterior knee pain, and the pain was released after the appropriate treatment. No deep infection happened in all cases. A total of 145 patients (145 knees) were followed up for 5 years to 8 years. The HSS score was 87.5 ± 8.2 at the end of the follow-up, showing significant difference (P lt; 0.05). The average range of motion was 95º (ranging from 90º to 110º). Partial radiolucencies occurred at the tibia side in 18knees 3 to 6 months after the operation. Among them, the width was less than 2 mm in 15 knees without symptom, and more than 2 mm in 3 knees. There were 2 of the 3 knees which were revised at the tibia side because of the aseptic loosing, while 1 patient had only mild pain in the knee during the follow-up, with no sign of loosing. Conclusion The mid-term effect of cementless TKA is satisfactory. The ingrowth of femur and tibial bones is rel iable. The early stage migration of the component is the main reason of loosing. Satisfying outcomes can also be achieved without patella replacement during TKA.
Objective To summarize the clinical outcome of the Ribbed anatomic cementless total hip arthroplasty (THA) in the treatment of hip-joint disease. Methods From January 2001 to June 2005, 34 patients(38 hips) with hip-joint disease were treated with Ribbed anatomic cementless THA. Their ages ranged from 29 to 55 years with an average age of 42.7 years.The disease course was from 3 to 18 years. Among these cases, there were 7 cases (7 hips) of femoral neck fracture, 5 cases(5 hips) of traumatic arthritis after fracture of acetabulum, 15 cases(16 hips) of necrosis of the femoral head and 7 cases(10 hips) of ankylosing spondylitis. Four patients were operated on both hip joints. The average Harris hip score was 38.6(25-57) before operation. Results Twenty-one patients(23 hips) were followed up 861 months with an average of 35 months. The Harris hip score was 76-98 after operation with an average of 92.3, showing significant difference when compared with that before operation(Plt;0.05). The excellent and good result was achieved in 93.5 % of patients. Radiographs showed no prosthetic osteolysis and no evidence of loosening. Pain in the thigh occurred in 4 patients,and it can be relieved by using nonsteroid antiinflammatory drug. Conclusion Ribbed anatomic cementless THA has good clinical and radiographic results in treating patients with hip-joint disease.
ObjectiveTo investigate the feasibility and mechanical properties of polymethyl methacrylate (PMMA) bone cement and allogeneic bone mixture to strengthen sheep vertebrae with osteoporotic compression fracture.MethodsA total of 75 lumbar vertebrae (L1-L5) of adult goats was harvested to prepare the osteoporotic vertebral body model by decalcification. The volume of vertebral body and the weight and bone density before and after decalcification were measured. And the failure strength, failure displacement, and stiffness were tested by using a mechanical tester. Then the vertebral compression fracture models were prepared and divided into 3 groups (n=25). The vertebral bodies were injected with allogeneic bone in group A, PMMA bone cement in group B, and mixture of allogeneic bone and PMMA bone cement in a ratio of 1∶1 in group C. After CT observation of the implant distribution in the vertebral body, the failure strength, failure displacement, and stiffness of the vertebral body were measured again.ResultsThere was no significant difference in weight, bone density, and volume of vertebral bodies before decalcification between groups (P>0.05). After decalcification, there was no significant difference in bone density, decreasing rate, and weight between groups (P>0.05). There were significant differences in vertebral body weight and bone mineral density between pre- and post-decalcification in 3 groups (P<0.05). CT showed that the implants in each group were evenly distributed in the vertebral body with no leakage. Before fracture, the differences in vertebral body failure strength, failure displacement, and stiffness between groups were not significant (P>0.05). After augmentation, the failure displacement of group A was significantly greater than that of groups B and C, and the failure strength and stiffness were less than those of groups B and C, the failure displacement of group C was greater than that of group B, and the failure strength and stiffness were less than those of group B, the differences between groups were significant (P<0.05). Except for the failure strength of group A (P>0.05), the differences in the failure strength, failure displacement, and stiffness before fracture and after augmentation in the other groups were significant (P<0.05).ConclusionThe mixture of allogeneic bone and PMMA bone cement in a ratio of 1∶1 can improve the strength of the vertebral body of sheep osteoporotic compression fractures and restore the initial stiffness of the vertebral body. It has good mechanical properties and can be used as one of the filling materials in percutaneous vertebroplasty.
Objective To explore the cause of haematoma after the cemented total hip arthroplasty (THA) and find out the way to decrease the incidence of haematoma perioperatively. Methods From March 2000 to October 2006, 103 patientswere treated with the cemented THA. Among the patients, 44 were males and 59 were females with their ages ranging from 36 to 89 years, averaged 55.3 years.The femoral neck fracture (Garden 4) was found in 49 patients, avascular necrosis of the femoral head (Ficat 4) in 26, and osteoarthritis of the hip joint (Tonnis 3) in 28. Their illness course ranged from 1 day to 8 years. The average Harris score preoperatively was 36 (range, 1948). The patients were divided into Group A (n=43) and Group B (n=60). The patients in Group A underwent the conventional surgical operations from March 2000 to December 2003; the patients in Group Bunderwent the same surgical procedures combined with additional procedures (e.g., ligation of the external rotators before incision, use of plastic bandage after the drainage tube was pulled out, prolonged stay period in bed postoperatively) from January 2004 to October 2006. Results In Group A, postoperative haematoma occurred in 9 patients and the averaged 317.8±75.3 ml(range,110-410 ml) of the accumulated blood was drained with a syringe. An average amount for the firstdrainage of the accumulated blood was 86.7±30.7 ml(range, 50-125 ml)， and an average drainage time was 4.2(range, 2-7). In Group B, postoperative haematoma occurred in 2 patients, with an amount of 110 ml and 160 ml of the accumulated blood and an amount of 40 ml and 60 ml of the drained blood at thefirst drainage. There was statistical difference in the amount of heamotoma between two groups(P＜0.05). The followup of 91 patients (39 in Group A, 52 in Group B) for 1.2-5.5 years (average, 3.7 years) revealed that the Harris scores were 78 in Group A and 85 in Group B on average.The Harris score for pain was 44 (Grade A) in 16 patients, 40 (Grade B) in 24 patients, and 30 (Grade C) in 3 patients in Group A; Grade A in 48 patients,Grade B in 12 patients, and Grade C in none of the patients in Group B. There was no statistical difference in Harris score between the two groups (P＞0.05). Conclusion Additional surgical procedures for the cemented THA, such as ligation of the external rotators before incision, use of plastic bandage afterthe drainage tube is pulled out, and prolonged stay in bed postoperatively, can greatly help to reduce the incidence of postoperative haematoma and the amount of the accumulated blood.
Objective To prepare a new injectable carbonated hydroxyapatite cement（CHC） which can set in situ and has porous configuration. Methods To prepare an in situ setting porous CHC（PCHC）, the 0.35% P-chitosan（PC） were added to make injectable PCHC(IPCHC). And the biocompatibility, PH value, time of solidify, mechanical property, chemical component, molecular structure, porous configuration, injectability and anti-washout ability were tested. Results 0.35%PC as a adjuvant was added to pore agent to prepare IPCHC. The porosity character and its injectability can be controlled by adjustment of the component. The test results demonstrate that the self-setting composition of this cement is carbonated hydroxyapatite, which is similar with natural cancellous bone. The porosity is 37.2% with interconnect pores; the setting time is 12 to 16 minutes, which is suitable for surgical application; the compressive strength is 4.3±2.6 Mpa, which is equal to that of cancellous bone; the cytotoxicity tests show an excellent biocompatibility; the concentration of CO32- is 5.6%, which is close to that of natural bone hydroxyapatite; the injection index of IPCHC is 95.13%±1.11%, which is significantly higher than that of PCHC(68.78％±2.19％); and IPCHC has good anti-washout ability. Conclusion Adding 0.35% PC to the liquid phase ofthe cement can improve its injectability greatly, and obtain a good antiwashout result. The IPCHC is useful to reconstruct nonloading bone defects in miniinvasive surgery, especially for the blooding site.
Objective To explore the correlative factors affecting the compl ications resulting from cement leakage after percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral body compression fractures (OVCF). Methods From February 2005 to October 2008, 71 patients with OVCF were treated by PKP and were retrospectively analyzed. There were 16 males and 55 females, and the average age was 71.5 years (range, 52-91 years). The average duration of disease was 5.7 months (range, 1-11 months). A total of 171 vertebra were involved in fracture including 19 cases of single vertebral fractures, 21 cases of double vertebral fractures, 20 cases of three vertebral fractures, and 11 cases of more than three vertebral fractures. All the treated vertebra were divided into acute (86 vertebra) or subacute (85 vertebra) state based on changes in MRI signal intensity. There was no radiculopathy or myelopathy. The average injected cement volumewas 4.6 mL (range, 1.5-6.5 mL). The treatment efficacy was assessed by observing the change in anterior and middle vertebral column height, Cobb angle, visual analogue scale (VAS) and Oswestry functional score at preoperation, 3 days after operation and last follow-up. The patients were divided into cement leakage group and no cement leakage group. All the compl ications were recorded, and then the correlative factors affecting the compl ications were analyzed. Results All the cases had rapid and significant improvement in back pain following PKP. All patients were followed up for 14 months (range, 7-18 months). There was no cement extravasation resulting in radiculopathy or myelopathy. Four patients (5.63%) had lung-related compl ications. During the follow-up, 9 recurrence vertebral fractures were observed in 6 patients (8.45%). The anterior and middle vertebral column height, Cobb angle, VAS and Oswestry score were significantly improved when compared with preoperation (P lt; 0.05). Cement leakage occurred in 17 (9.94%) vertebral bodies; of 17 cases, the cement leaked into the paravertebral space in 7 cases, intervertebral space in 6 cases, channel of needl ing insertion in 3 cases, and spinal canal in 1 case. Univariate analysis showed statistically significant differences (P lt; 0.05) in preoperative anterior and middle vertebral column height, injected cement volume and vertebral body wall incompetence between the cement leakage group and no cement leakage group. There were no significant differences (P gt; 0.05) in preoperative Cobb angle, freshness of vertebral fracture, location of operative vertebrae and operative approach between the two groups. Multiple logistic regression analysis showed that the injected cement volume [odds ratio (OR)=3.105, 95% confidence interval (CI)=1.674-5.759, P lt; 0.01] and vertebral body wall incompetence (OR=11.960, 95%CI=3.512-40.729, P lt; 0.01) were the predominant variable associated with the compl ications resulted fromcement leakage. Conclusion The injected cement volume and vertebral body wall incompetence were the factors affecting the compl ications. The improvement of surgical technique is the capital factor that may reduce the compl ications in the PKP.
Calcium phosphate cement (CPC) has been widely used as bone fillers because of its excellent bioactivity and biocompatibility. Meanwhile, CPC is also an attractive candidate for the incorporation of drug or microspheres, because the preparing procedure avoids sintering and heating release. This paper summarizes the clinical applications of microspheres incorporated in CPC from the aspects of sustained drug release, accelerated degradation, porous structure and improved mechanical properties. The paper is aimed to analyze the methods and principles of microspheres loaded CPC, and so as to lay a foundation for the further research of improving and manufacturing the CPC with ideal properties.
Objective To review the progress of the pedicle screw augmentation technique by bone cement. Methods Recent literature about the pedicle screw augmentation technique by bone cement was reviewed and analysed. The characters were summarized. Results Pedicle augmentation technique includes the augmentation of ordinary solid pedicle screw and hollow pedicle screw. Both types could increase the fixation strength and gain satisfactory clinical results. Bone cement leakage had a certain incidence rate, but most of cases were asymptom. Conclusion Bone cement augmentation of pedicle screw is an effective and safe internal fixation for poor bone condition.