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.
Open reduction and internal fixation with plate and screw is one of the most widely used surgical methods in the treatment of proximal humeral fractures in the elderly. In recent years, more and more studies have shown that it is very important to strengthen the medial column support of the proximal humerus during the surgery. At present, orthopedists often use bone graft, bone cement, medial support screw and medial support plate to strengthen the support of the medial column of the proximal humerus when applying open reduction and internal fixation with plate and screw to treat proximal humeral fractures. Therefore, the methods of strengthening medial column support for proximal humerus fractures and their effects on maintaining fracture reduction, reducing postoperative complications and improving functional activities of shoulder joints after operation are reviewed in this paper. It aims to provide a certain reference for the individualized selection of medial support methods according to the fracture situation in the treatment of proximal humeral fractures.
Objective To evaluate the biomechanicalproperties and structuralcharacteristics of various composites of partially decalcified allogenic bone matrix gelatin and bone cement at different ratios. Methods According to Urist method, partially decalcified allogenic bone matrix gelatin was prepared and mixedwith bone cement at different ratios of 0, 400, 500, and 600mg/g. Then the comparisons of these composites were performed in microstructure, ultimate compression strength and ultimate bending strength properties. Results The electronic microscope showed that the bone particles and bone cement were distributed evenly in the composite, irregularly connecting by multiple points; with the increase ofbone particles and decrease of bone cement in the composite, there were more and more natural crevices, varying from 100 μm to 400 μm in width, in the biomaterials. Of all the composites with the ratios of 0, 400,500, and 600 mg/g, the measurements of ultimate compression strength were (71.7±2.0) MPa, (46.9±3.3) MPa, (39.8±4.1) MPa, and (32.2±3.4) MPa, respectively; and the measurements ofultimate bending strength were (65.0±3.4) MPa, (38.2±4.0) MPa, (33.1±4.3) MPa and (25.3±4.6) MPa, respectively. Conclusion The compositeof partially decalcified allogenic bone matrix gelatin and bone cement has a good biomechanical property and could be easily fabricated and re-shaped, which make it available to be used clinically as an idea bone graft biomaterial.
ObjectiveTo determine the feasibility of fabricating molds using a three-dimensional (3D) printer for producing customized bone cement for repairing bone defect. MethodsBetween February 2015 and March 2016, 13 patients with bone defects were treated. There were 9 males and 4 females with an average age of 38.4 years (range, 20-58 years), including 7 cases of chronic osteomyelitis, 3 cases of bone tuberculosis, 2 cases of bone tumor, and 1 case of ischemic necrosis. The defect located at the humerus in 3 cases, at the femur in 4 cases, and at the tibia in 6 cases. The defect ranged from 4.5 to 8.9 cm in length (mean, 6.7 cm). Before operation, Mimics10.01 software was used to design cement prosthesis, 3-matic software to design shaping module which was printed by 3D technology. After removal of the lesion bone during operation, bone cement was filled into the shaping module to prepare bone cement prosthesis for repairing defect. ResultsThe measurement result from Image J software showed that the match index of interface between the mirror restored digital and bone interface was 95.1%-97.4% (mean, 96.3%); the match index of interface between bone cement prosthesis and bone interface was 91.2%-94.7% (mean, 93.2%). It was one time success during separation between formed bone cement and shaping module without any shatter or fall off. All incisions healed by first intention. The cases were followed up 5-17 months (mean, 9.4 months). X-ray films and CT scans showed good position of bone cement prosthesis without any fracture; no peripheral fracture occurred. Conclusion3D printing customized bone cement shaping module can shorten the operation time, and customized bone cement prothesis has good match with bone interface, so it can avoid further adjustment and accord with the biomechanical rules of surgical site.
ObjectiveTo explore the safety and effectiveness of graded infusion of bone cement in the unipedicular percutaneous vertebroplasty (PVP) for Kummell's disease. MethodsEighteen patients with Kummell's disease were treated by unipedicular PVP with graded infusion of bone cement between January 2012 and January 2014. Of 18 cases, 6 were male and 12 were female, aged from 65 to 88 years (mean, 75 years), with a disease duration from 3 to 32 months (mean, 11.6 months). The bone mineral density was measured by dual-energy X-ray absorptiometry; the T value ranged from -4.0 to -2.8 (mean, -3.4). Affected segments included T11 in 3 cases, T12 in 10 cases, L1 in 3 cases, and L2 in 2 cases. X-ray films were taken after operation to observe bone cement leakage and anterior height changes of affected vertebrae. Visual analogue scale (VAS) and Oswestry disability index (ODI) were used to assess pain status and functional activity. ResultsAll cases underwent smoothly unipedicular PVP and were followed up 12-26 months (mean, 14 months). Cement leakage occurred in 4 patients, including 1 case of anterior paravertebral soft tissue leakage, 2 cases of intervertebral disc leakage, and 1 case of canal venous leakage, but there was no other complications. The anterior height of affected vertebrae were significantly improved (P<0.05) from 29.1%±6.7% at preoperation to 68.1%±7.3% at 3 days after operation and 67.8%±5.9% at last follow-up; the VAS scores were significantly decreased (P<0.05) from 8.11±1.32 at preoperation to 2.14±0.78 at 3 days and 1.97± 0.50 at last follow-up; and ODI were significantly decreased (P<0.05) from 84.6%±8.5% to 24.1%±9.7% and 23.8%±10.2%; but no significant difference was found between at 3 days and at last follow-up (P>0.05). ConclusionGraded infusion of bone cement in unipedicular PVP is a safe and effective procedure for Kummell's disease and this technique could decrease the incidence of bone cement leakage.
Objective To research the feasibility and effectiveness of percutaneous kyphoplasty (PKP) by improved injecting tube through unipedicular puncturing. Methods Between January 2012 and Junuary 2016, 60 cases (68 vertebrae) of osteoporotic vertebral compression fractures (OVCF) were treated. PKP was performed through unipedicular puncturing with routine injecting tube in 30 cases (34 vertebrae, routine group), and with improved injecting tube in 30 cases (34 vertebrae, improved group). There was no significant difference in age, gender, disease duration, fracture level, preoperative visual analogue scale (VAS), or vertebral height between 2 groups (P>0.05). The operation time, the volume of bone cement injected, preoperative and postoperative VAS, and preoperative and postoperative vertebral height, and postoperative distribution coefficient of bone cement were recorded and compared between 2 groups. Results Good healing of puncture points was achieved in 2 groups after PKP, and no serious complication occurred. There was no significant difference in operation time and the volum of bone cement injected between 2 groups (t=0.851,P=0.399;t=1.672,P=0.101). Bone cement leakage was observed in 2 cases of 2 groups respectively. The distribution coefficient of bone cement in routine group was significantly less than that in improved group (t=13.049,P=0.000). All patients were followed up 12-36 months (mean, 19 months). The postoperative VAS and vertebral height were significantly improved when compared with preoperative ones in 2 groups (P<0.05), but there was no significant difference in VAS between at 2 days after operation and at last follow-up, in vertebral height between at 2 days after operation and at 1 year after operation, and between 2 groups after operation (P>0.05). X-ray films showed vertebral compression fractures in 6 cases of routine group and in 1 case of improved group during follow-up. Conclusion PKP by improved injecting tube through unipedicular puncturing can improve the distribution of bone cement, restore the height and strength of vertebral body, and reduce the incidence of re-fracture.
ObjectiveTo evaluate the effect of bone cement filling on articular cartilage injury after curettage of giant cell tumor around the knee. MethodsFifty-three patients with giant cell tumor who accorded with the inclusion criteria were treated between January 2000 and December 2011, and the cl inical data were retrospectively analyzed. There were 30 males and 23 females, aged 16-69 years (mean, 34.2 years). The lesion located at the distal femur in 28 cases and at the proximal tibia in 25 cases. According to Campanacci grade, there were 6 patients at grade I, 38 at grade Ⅱ, and 9 at grade Ⅲ. Of 53 patients, 42 underwent curettage followed by bone cement fill ing, and 11 received curettage followed by bone grafts in the subchondral bony area and bone cement fill ing. Two groups were divided according to whether secondary osteoarthritis occurred or not during postoperative follow-up. The gender, age, lesion site, the subchondral residual bone thickness, tumor cross section, preoperative Campanacci grade, subchondral bone graft, and Enneking function score were compared between 2 groups, and multivariate logistic regression analysis was done. ResultsAll incisions healed by first intention. The average follow-up time was 65 months (range, 23-158 months). Of 53 cases, 37 (69.8%) had no osteoarthritis, and 16 (30.2%) had secondary osteoarthritis. Three cases (5.7%) recurred during the follow-up period. Univariate logistic regression analysis showed no significant difference in gender, age, lesion site, and Campanacci grade between 2 groups (P>0.1); difference was significant in the subchondral residual bone thickness, tumor cross section, Enneking function score, and subchondral bone graft (P<0.1). The multivariate logistic regression analysis showed that the decreased subchondral residual bone thickness, the increased tumor cross section, and no subchondral bone graft are the risk factors of postoperative secondary osteoarthritis (P<0.05). ConclusionCurettage of giant cell tumor around the knee followed by bone cement filling can increase the damage of cartilage, and subchondral bone graft can delay or reduce cartilage injury.
ObjectiveTo explore the safety and effectiveness of polymethylmethacrylate-augmented screw fixation (PASF) in the treatment of elderly thoracolumbar tuberculosis combined with severe osteoporosis.MethodsThe clinical data of 20 elderly patients with thoracolumbar tuberculosis and severe osteoporosis who underwent PASF after anterior or posterior debridement and bone grafting and met the selection criteria between December 2012 and December 2014 were retrospectively analyzed. There were 8 males and 12 females with an average age of 68.5 years (range, 65-72 years). T value of bone mineral density was −4.2 to −3.6, with an average of −3.9. There were 12 cases of thoracic tuberculosis, 3 cases of thoracolumbar tuberculosis, and 5 cases of lumbar tuberculosis. The diseased segments involved T3-L4, including 11 cases of single-segment disease, 6 cases of double-segment disease, and 3 cases of multi-segment disease. The disease duration was 3-9 months, with an average of 6 months. The preoperative spinal nerve function of the patients was evaluated by the American Spinal Injury Association (ASIA) grading. There were 2 cases of grade A, 5 cases of grade B, 6 cases of grade C, 4 cases of grade D, and 3 cases of grade E. Postoperative imaging examination was used to evaluate the bone graft fusion and paravertebral abscess absorption, and to measure the Cobb angle of the segment to evaluate the improvement of kyphosis. The levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were tested. The visual analogue scale (VAS) score, Oswestry disability index (ODI), and ASIA grading were used to evaluate the effectivreness before operation, at 1 month after operation, and at last follow-up. The clinical cure of tuberculosis was also evaluated.ResultsAll operation successfully completed. The operation time was 154-250 minutes, with an average of 202 minutes; the intraoperative blood loss was 368-656 mL, with an average of 512 mL. All 20 patients were followed up 18-42 months, with an average of 26.8 months. The postoperative pain and symptoms of tuberculosis in all patients relieved, and the paravertebral abscess was absorbed, reaching the cure standard for spinal tuberculosis. All bone grafts fusion achieved within 1 year after operation. Only 1 case had asymptomatic bone cement leakage into the paravertebral veins, and the remaining patients had no serious complications such as bone cement leakage in the spinal canal, pulmonary embolism, and neurovascular injury. At last follow-up, spinal cord nerve function significantly improved when compared with preoperative one. Among them, ASIA grading were 7 cases of grade C, 8 cases of grade D, and 5 cases of grade E, showing significant difference when compared with preoperative one (Z=2.139, P=0.000). VAS score, ODI score, segmental Cobb angle, ESR, and CRP at 1 month after operation and at last follow-up were significantly improved when compared with preoperative ones (P<0.05); there was no significant difference between 1 month after operation and last follow-up (P>0.05). During the follow-up, no complications such as failure of internal fixation, proximal junctional kyphosis, or tuberculosis recurrence occurred.ConclusionFor elderly patients with thoracolumbar tuberculosis and severe osteoporosis, PASF treatment is safe and effective.
ObjectiveTo explore the effectiveness of induced membrane technique of hollow porous antibioticimpregnated bone cement forming in vitro and lavage in vivo for the treatment of osteomyelitis. MethodsBetween January 2010 and March 2014, 14 cases of osteomyelitis were treated by induced membrane technique of hollow porous antibiotic-impregnated bone cement forming in vitro and lavage in vivo after debridement at the first stage, then the bone cement with bone graft was replaced during the induced membrane after infection was controlled at the second stage. The time from first to second stage operation was 8-12 weeks (average, 10.2 weeks). There were 11 males and 3 females, aged 18 to 69 years (average, 39.2 years). According to Cierny-Mader classification of osteomyelitis, 2 cases were rated as intramedullary type, 5 cases as limited type, and 7 cases as diffusing type. The course of osteomyelitis was 3 months to 20 years, averaged 1.9 years. The healing of bone defect and the functionary recovery of adjacent joint were evaluated according to Paley's method. ResultsDebridement was performed for two times in 1 case, and for one time in 13 cases for control of bone infection at the first stage. All incisions healed by first intention after second stage. All patients were followed up 15-48 months (average, 13.4 months), with no recurrence of infection. All bone defects healed, and the clinical healing time was 4-5 months (average, 4.4 months). The results of bone healing grade were excellent in all cases at 1 year after operation; the functional recovery of adjacent joint at last follow-up was excellent in 4 cases, good in 8 cases, and fair in 2 cases, and the excellent and good rate was 85.7%. ConclusionInduced membrane technique of hollow porous antibiotic-impregnated bone cement forming in vitro and lavage in vivo for treatment of osteomyelitis has the advantages of high rate of elution of antibiotics, ease of lavage of medullary cavity, and no damage to induced membrane and bony interface between bone and bone cement when removing cement, it is effective for control of bone infection and repair of bone defect.
Objective To study the methods of promoting the injectability of calcium phosphate cement.Methods Evaluation methods of bone cements, injectability and methods of promoting injectability were reviewed by extensive investigating of latest literatures.Results It was very important to improve the injectability of calcium phosphate cement. Commonly used methods to evaluate the injectability included testing injectability coefficient, pushing force and injection pressure.Injectability of calcium phosphatecement were promoted by increasing liquid/solid ratio, modulating the componentof solid or liquid phase, and adding various additives.Conclusion Promoting the injectability of calcium phosphate cement is the clinical requirement.